Science.gov

Sample records for active external rotation

  1. Strength and muscle activity of shoulder external rotation of subjects with and without scapular dyskinesis

    PubMed Central

    Uga, Daisuke; Nakazawa, Rie; Sakamoto, Masaaki

    2016-01-01

    [Purpose] This study aimed to clarify the relationship between scapular dyskinesis and shoulder external rotation strength and muscle activity. [Subjects and Methods] Both shoulders of 20 healthy males were evaluated. They were classified into 19 normal, 8 subtly abnormal, and 13 obviously abnormal shoulders using the scapular dyskinesis test. Subtly abnormal shoulders were subsequently excluded from the analysis. Shoulder external rotation strength and muscle activity (infraspinatus, serratus anterior, upper, middle, and lower trapezius) were measured in 2 positions using a handheld dynamometer and surface electromyography while sitting in a chair with shoulder 0° abduction and flexion (1st position), and while lying prone on the elbows with the shoulders elevated in the zero position (zero position). The strength ratio was calculated to quantify the change in strength between the positions (zero position / 1st position). [Results] In the obviously abnormal shoulder group, the strength in the 1st position was significantly stronger, the strength ratio was significantly smaller, and the serratus anterior in the zero position showed significantly lower activity than the normal shoulder group. [Conclusion] In shoulder external rotation in the zero position, in obviously abnormal shoulders, the serratus anterior is poorly recruited, weakening the shoulder external rotation strength. PMID:27190434

  2. Shoulder External Rotation Fatigue and Scapular Muscle Activation and Kinematics in Overhead Athletes

    PubMed Central

    Joshi, Mithun; Thigpen, Charles A.; Bunn, Kevin; Karas, Spero G.; Padua, Darin A.

    2011-01-01

    Context: Glenohumeral external rotation (GH ER) muscle fatigue might contribute to shoulder injuries in overhead athletes. Few researchers have examined the effect of such fatigue on scapular kinematics and muscle activation during a functional movement pattern. Objective: To examine the effects of GH ER muscle fatigue on upper trapezius, lower trapezius, serratus anterior, and infraspinatus muscle activation and to examine scapular kinematics during a diagonal movement task in overhead athletes. Setting: Human performance research laboratory. Design: Descriptive laboratory study. Patients or Other Participants: Our study included 25 overhead athletes (15 men, 10 women; age = 20 ± 2 years, height = 180 ± 11 cm, mass = 80 ± 11 kg) without a history of shoulder pain on the dominant side. Interventions: We tested the healthy, dominant shoulder through a diagonal movement task before and after a fatiguing exercise involving low-resistance, high-repetition, prone GH ER from 0° to 75° with the shoulder in 90° of abduction. Main Outcome Measure(s): Surface electromyography was used to measure muscle activity for the upper trapezius, lower trapezius, serratus anterior, and infraspinatus. An electromyographic motion analysis system was used to assess 3-dimensional scapular kinematics. Repeated-measures analyses of variance (phase × condition) were used to test for differences. Results: We found a decrease in ascending-phase and descending-phase lower trapezius activity (F1,25 = 5.098, P = .03) and an increase in descending-phase infraspinatus activity (F1,25 = 5.534, P = .03) after the fatigue protocol. We also found an increase in scapular upward rotation (F1,24 = 3.7, P = .04) postfatigue. Conclusions: The GH ER muscle fatigue protocol used in this study caused decreased lower trapezius and increased infraspinatus activation concurrent with increased scapular upward rotation range of motion during the functional task. This highlights the interdependence of scapular

  3. Spatiotemporal differences of brain activation between internal and external strategies in mental rotation: A behavioral and ERD/ERS study.

    PubMed

    Wang, Zhuo; Guo, Xiaoli; Lyu, Yuanyuan; Chen, Hongzhou; Tong, Shanbao

    2016-06-01

    Subjects may voluntarily implement an internal or external strategy during mental rotation (MR) task. However, few studies have reported the spatiotemporal differences of brain activation between the two MR strategies. This study aims to compare the two strategies from the perspective of behavioral performance and spatiotemporal brain activations in each cognitive sub-stage using EEG measurements. Both the internal (IN) and external (EX) groups showed a significant 'angle effect' on reaction time (RT) and accuracy (ACC). However, a smaller increase of RT with rotation angle was observed in the EX group. Event-related (de)synchronization in the beta band revealed similar temporal patterns of brain activation in the two groups, but with a stronger activation in the MR sub-stage in the EX group. We speculate that MR of 3D abstract objects is easier when an external strategy is used, and would be promoted by an additional visual-spatial process involving the parietal-occipital areas. Our results suggested that the differences between the two strategies were mainly induced by main MR rather than other cognitive processes. PMID:27132083

  4. Influence of hip external rotation on hip adductor and rectus femoris myoelectric activity during a dynamic parallel squat.

    PubMed

    Pereira, Glauber Ribeiro; Leporace, Gustavo; Chagas, Daniel das Virgens; Furtado, Luis F L; Praxedes, Jomilto; Batista, Luiz A

    2010-10-01

    This study sought to compare the myoelectric activity of the hip adductors (HAs) and rectus femoris (RF) when the hip was in a neutral position or externally rotated by 30° or 50° (H0, H30, and H50, respectively) during a parallel squat. Ten healthy subjects performed 10 repetitions of squats in each of the 3 hip positions and the myoelectric activities of the HAs and RF were recorded. The signal was then divided into categories representing concentric (C) and eccentric (E) contractions in the following ranges of motion: 0-30° (C1 and E1), 30-60° (C2 and E2), and 60-90° (C3 and E3) of knee flexion. From those signals, an root mean square (RMS) value for each range of motion in each hip position was obtained. All values were normalized to those obtained during maximum voluntary isometric contraction. We found that HAs showed a significant increase in myoelectric activity during C3 and E3 in the H30 and H50 positions, as compared with H0. Meanwhile, RF activity did not significantly differ between hip positions. Both muscles showed higher activation during 60-90° (C3 and E3) of knee flexion, as compared with 0-30° (C1 and E1) and 30-60° (C2 and E2). The results suggest that if the aim is to increase HA activity despite the low percentage of muscle activation, squats should be performed with 30° of external rotation and at least 90° of knee flexion. PMID:20651607

  5. Differences in Muscle Activities of the Infraspinatus and Posterior Deltoid during Shoulder External Rotation in Open Kinetic Chain and Closed Kinetic Chain Exercises.

    PubMed

    Kang, Min-Hyeok; Oh, Jae-Seop; Jang, Jun-Hyeok

    2014-06-01

    [Purpose] This study investigated the changes in electromyographic (EMG) activities of the infraspinatus and posterior deltoid muscles during shoulder external rotation under open kinetic chain (OKC) and closed kinetic chain (CKC) exercise conditions. [Subjects] In total, 15 healthy males participated in this study. [Methods] Subjects performed shoulder external rotations under CKC and OKC conditions while standing with and without weight support provided by a height-adjustable table. Pressure biofeedback was used to ensure a constant amount of weight support. The activities of the infraspinatus and posterior deltoid muscles during shoulder external rotation were measured using a wireless surface EMG system. The paired t-test was used to compare the EMG activities of the infraspinatus and the posterior deltoid muscles and the ratio of the infraspinatus to the posterior deltoid during shoulder external rotation under OKC and CKC conditions. [Results] The EMG activity of the infraspinatus and the ratio of the infraspinatus to the posterior deltoid activities were significantly increased, whereas the posterior deltoid activity was significantly decreased under the CKC condition compared to the OKC condition. [Conclusion] Clinicians should consider the CKC shoulder external rotation exercise when they wish to selectively strengthen the infraspinatus. PMID:25013291

  6. The effects of hip external rotator exercises and toe-spread exercises on lower extremity muscle activities during stair-walking in subjects with pronated foot

    PubMed Central

    Goo, Young-Mi; Kim, Da-Yeon; Kim, Tae-Ho

    2016-01-01

    [Purpose] The purpose of the present study was to examine the effects of toe-spread (TS) exercises and hip external rotator strengthening exercises for pronated feet on lower extremity muscle activities during stair-walking. [Subjects and Methods] The participants were 20 healthy adults with no present or previous pain, no past history of surgery on the foot or the ankle, and no foot deformities. Ten subjects performed hip external rotator strengthening exercises and TS exercises and the remaining ten subjects performed only TS exercises five times per week for four weeks. [Results] Less change in navicular drop height occurred in the group that performed hip external rotator exercises than in the group that performed only TS exercises. The group that performed only TS exercises showed increased abductor hallucis muscle activity during both stair-climbing and -descending, and the group that performed hip external rotator exercises showed increased muscle activities of the vastus medialis and abductor hallucis during stair-climbing and increased muscle activity of only the abductor hallucis during stair-descending after exercise. [Conclusion] Stair-walking can be more effectively performed if the hip external rotator muscle is strengthened when TS exercises are performed for the pronated foot. PMID:27134364

  7. Muscle activity response to external moment during single-leg drop landing in young basketball players: the importance of biceps femoris in reducing internal rotation of knee during landing.

    PubMed

    Fujii, Meguru; Sato, Haruhiko; Takahira, Naonobu

    2012-01-01

    Internal tibial rotation with the knee close to full extension combined with valgus collapse during drop landing generally results in non-contact anterior cruciate ligament (ACL) injury. The purpose of this study was to investigate the relationship between internal rotation of the knee and muscle activity from internal and external rotator muscles, and between the internal rotation of knee and externally applied loads on the knee during landing in collegiate basketball players. Our hypothesis was that the activity of biceps femoris muscle would be an important factor reducing internal knee rotation during landing. The subjects were 10 collegiate basketball students: 5 females and 5 males. The subjects performed a single-leg drop landing from a 25-cm height. Femoral and tibial kinematics were measured using a 3D optoelectronic tracking system during the drop landings, and then the knee angular motions were determined. Ground reaction forces and muscle activation patterns (lateral hamstring and medial hamstring) were simultaneously measured and computed. Results indicated that lower peak internal tibial rotation angle at the time of landing was associated with greater lateral hamstring activity (r = -0.623, p < 0.001). When gender was considered, the statistically significant correlation remained only in females. There was no association between the peak internal tibial rotation angle and the knee internal rotation moment. Control of muscle activity in the lateral to medial hamstring would be an important factor in generating sufficient force to inhibit excessive internal rotation during landing. Strengthening the biceps femoris might mitigate the higher incidence of non-contact ACL injury in female athletes. Key pointsLower activity of the external rotator muscle of the knee, which inhibits internal rotation of the knee, may be the reason why females tend to show a large internal rotation of the knee during drop landing.Externally applied internal rotation moment of

  8. The Hillman Rotation: An External Clinic Model.

    ERIC Educational Resources Information Center

    Sears, Joan M.; Veith, Jack

    2000-01-01

    Describes the external optometric education program at the Sidney Hillman Health Centre (Chicago, Illinois). Discusses the history of the clinic, its administrative and educational philosophy, and its affiliation with two prominent hospitals and the Illinois College of Optometry. (DB)

  9. Rotating copper plasmoid in external magnetic field

    SciTech Connect

    Pandey, Pramod K.; Thareja, Raj K.

    2013-02-15

    Effect of nonuniform magnetic field on the expanding copper plasmoid in helium and argon gases using optical emission spectroscopy and fast imaging is presented. We report a peculiar oscillatory rotation of plasmoid in magnetic field and argon ambient. The temporal variation and appearance of the dip in the electron temperature show a direct evidence of the threading and expulsion of the magnetic field lines from the plasmoid. Rayleigh Taylor instability produced at the interface separating magnetic field and plasma is discussed.

  10. The flow external to a rotating torus

    NASA Astrophysics Data System (ADS)

    Calabretto, Sophie A. W.; Denier, James P.; Mattner, Trent W.

    2016-08-01

    Imparting a sudden rotation to a torus (or other symmetric smooth object) in an otherwise quiescent, viscous fluid serves to generate boundary layers at the object's surface. These boundary layers are known to exhibit a finite-time singularity at the equator which manifests in a thickening of the boundary layer and subsequent development of an equatorial jet. Here we consider the post-collision flow dynamics, demonstrating that the equatorial jet serves to shed a finite amplitude toroidal vortex pair. The radial jet is also shown to develop an absolute instability at suitably high Reynolds numbers.

  11. Tidal deformation of a slowly rotating material body: External metric

    NASA Astrophysics Data System (ADS)

    Landry, Philippe; Poisson, Eric

    2015-05-01

    We construct the external metric of a slowly rotating, tidally deformed material body in general relativity. The tidal forces acting on the body are assumed to be weak and to vary slowly with time, and the metric is obtained as a perturbation of a background metric that describes the external geometry of an isolated, slowly rotating body. The tidal environment is generic and characterized by two symmetric trace-free tidal moments Ea b and Ba b, and the body is characterized by its mass M , its radius R , and a dimensionless angular-momentum vector χa≪1 . The perturbation accounts for all couplings between χa and the tidal moments. The body's gravitational response to the applied tidal field is measured in part by the familiar gravitational Love numbers K2el and K2mag , but we find that the coupling between the body's rotation and the tidal environment requires the introduction of four new quantities, which we designate as rotational-tidal Love numbers. All these Love numbers are gauge invariant in the usual sense of perturbation theory, and all vanish when the body is a black hole.

  12. Compensation to whole body active rotation perturbation.

    PubMed

    Rossi, S; Gazzellini, S; Petrarca, M; Patanè, F; Salfa, I; Castelli, E; Cappa, P

    2014-01-01

    The aim of the present study is the exploration of the compensation mechanisms in healthy adults elicited by superimposing a horizontal perturbation, through a rotation of the support base, during a whole body active rotation around the participant's own vertical body axis. Eight healthy participants stood on a rotating platform while executing 90° whole body rotations under three conditions: no concurrent platform rotation (NP), support surface rotation of ± 45° in the same (45-S) and opposite (45-O) directions. Participants' kinematics and CoP displacements were analyzed with an optoelectronic system and a force platform. In both 45-S and 45-O conditions, there was a tendency for the head to be affected by the external perturbation and to be the last and least perturbed segment while the pelvis was the most perturbed. The observed reduced head perturbation in 45-S and 45-O trials is consistent with a goal-oriented strategy mediated by vision and vestibular information, whereas the tuning of lumbar rotation is consistent with control mechanisms mediated by somato-sensory information.

  13. A Probabilistic Model of Glenohumeral External Rotation Strength for Healthy Normals and Rotator Cuff Tear Cases

    PubMed Central

    Langenderfer, Joseph E.; Carpenter, James E.; Johnson, Marjorie E.; An, Kai-nan; Hughes, Richard E.

    2006-01-01

    The reigning paradigm of musculoskeletal modeling is to construct deterministic models from parameters of an “average” subject and make predictions for muscle forces and joint torques with this model. This approach is limited because it does not perform well for outliers, and it does not model the effects of population parameter variability. The purpose of this study was to simulate variability in musculoskeletal parameters on glenohumeral external rotation strength in healthy normals, and in rotator cuff tear cases using a Monte Carlo model. The goal was to determine if variability in musculoskeletal parameters could quantifiably explain variability in glenohumeral external rotation strength. Multivariate Gamma distributions for musculoskeletal architecture and moment arm were constructed from empirical data. Gamma distributions of measured joint strength were constructed. Parameters were sampled from the distributions and input to the model to predict muscle forces and joint torques. The model predicted measured joint torques for healthy normals, subjects with supraspinatus tears, and subjects with infraspinatus–supraspinatus tears with small error. Muscle forces for the three conditions were predicted and compared. Variability in measured torques can be explained by differences in parameter variability. PMID:16474916

  14. Passive rotation of flagella on paralyzed Salmonella typhimurium (mot) mutants by external rotatory driving force.

    PubMed Central

    Ishihara, A; Yamaguchi, S; Hotani, H

    1981-01-01

    Salmonella typhimurium mot mutants are unable to rotate their flagella. Dark-field light microscopy showed that the flagella could be rotated passively by an external rotatory driving force. Images PMID:7007338

  15. Feedback suppression of rotating external kink instabilities in the presence of noise

    SciTech Connect

    Hanson, Jeremy M.; De Bono, Bryan; James, Royce W.; Levesque, Jeffrey P.; Mauel, Michael E.; Maurer, David A.; Navratil, Gerald A.; Pedersen, Thomas Sunn; Shiraki, Daisuke

    2008-08-15

    The authors report on the first experimental demonstration of active feedback suppression of rotating external kink modes near the ideal wall limit in a tokamak using Kalman filtering to discriminate the n=1 kink mode from background noise. The Kalman filter contains an internal model that captures the dynamics of a rotating, growing n=1 mode. Suppression of the external kink mode is demonstrated over a broad range of phase angles between the sensed mode and applied control field, and performance is robust at noise levels that render proportional gain feedback ineffective. Suppression of the kink mode is accomplished without excitation of higher frequencies as was observed in previous experiments using lead-lag loop compensation [A. J. Klein et al., Phys Plasmas 12, 040703 (2005)].

  16. Reliability of a New Clinical Instrument for Measuring Internal and External Glenohumeral Rotation

    PubMed Central

    Lindenfeld, Thomas N.; Fleckenstein, Cassie M.; Levy, Martin S.; Grood, Edward S.; Frush, Todd J.; Parameswaran, A. Dushi

    2015-01-01

    Background: The shoulder plays a critical role in many overhead athletic activities. Several studies have shown alterations in shoulder range of motion (ROM) in the dominant shoulder of overhead athletes and correlation with significantly increased risk of injury to the shoulder and elbow. The purpose of this study was to measure isolated glenohumeral joint internal/external rotation (IR/ER) to determine inter- and intraobserver reliability of a new clinical device. Hypothesis: (1) Inter- and intraobserver reliability would exceed 90% for measures of glenohumeral joint IR, ER, and total arc of motion; (2) the dominant arm would exhibit significantly increased ER, significantly decreased IR, and no difference in total arc of motion compared with the nondominant shoulder; and (3) a significant difference exists in total arc between male and female patients. Study Design: Case series. Level of Evidence: Level 4. Methods: Thirty-seven subjects (mean age, 23 years; range, 13-54 years) were tested by 2 orthopaedic surgeons. A single test consisted of 1 arc of motion from neutral to external rotation to internal rotation and back to neutral within preset torque limits. Each examiner performed 3 tests on the dominant and nondominant shoulders. Each examiner completed 2 installations. Results: Testing reliability demonstrated that neither trial, installation, nor observer were significant sources of variation. The maximum standard deviation was 1.3° for total arc of motion and less than 2° for most other measurements. Dominant arm ER was significantly greater than nondominant arm ER (P = 0.02), and dominant arm IR was significantly less than nondominant arm IR (P = 0.00). Mean total rotation was 162°, with no significant differences in total rotation between dominant and nondominant arms (P = 0.34). Mean total arc of motion was 45° greater in female subjects. Differences in total arc of motion between male and female subjects was statistically significant (P < 0

  17. Electromyographic analysis of the infraspinatus and scapular stabilizing muscles during isometric shoulder external rotation at various shoulder elevation angles

    PubMed Central

    Uga, Daisuke; Endo, Yasuhiro; Nakazawa, Rie; Sakamoto, Masaaki

    2016-01-01

    [Purpose] This study aimed to clarify activation of the infraspinatus and scapular stabilizing muscles during shoulder external rotation at various shoulder elevation angles. [Subjects] Twenty subjects participated in this study and all measurements were performed on the right shoulder. [Methods] Isometric shoulder external rotation strength and surface electromyographic data were measured with the shoulder at 0°, 45°, 90°, and 135° elevation in the scapular plane. The electromyographic data were collected from the infraspinatus, upper trapezius, middle trapezius, lower trapezius, and serratus anterior muscles. These measurements were compared across the various shoulder elevation angles. [Results] The strength measurements did not differ significantly by angulation. The infraspinatus activity was 92%, 75%, 68%, and 57% of the maximum voluntary contraction, which significantly decreased as shoulder elevation increased. The serratus anterior activity was 24%, 48%, 53%, and 62% of the maximum voluntary contraction, which significantly increased as shoulder elevation increased. [Conclusion] Shoulder external rotation torque was maintained regardless of shoulder elevation angle. The shoulder approximated to the zero position as the shoulder elevation increased so that infraspinatus activity decreased and the scapular posterior tilting by the serratus anterior might generate shoulder external rotation torque. PMID:26957748

  18. Numerical Study of Rotating Turbulence with External Forcing

    NASA Technical Reports Server (NTRS)

    Yeung, P. K.; Zhou, Ye

    1998-01-01

    Direct numerical simulation at 256(exp 3) resolution have been carried out to study the response of isotropic turbulence to the concurrent effects of solid-body rotation and numerical forcing at the large scales. Because energy transfer to the smaller scales is weakened by rotation, energy input from forcing gradually builds up at the large scales, causing the overall kinetic energy to increase. At intermediate wavenumbers the energy spectrum undergoes a transition from a limited k(exp -5/3) inertial range to k(exp -2) scaling recently predicted in the literature. Although the Reynolds stress tensor remains approximately isotropic and three-components, evidence for anisotropy and quasi- two-dimensionality in length scales and spectra in different velocity components and directions is strong. The small scales are found to deviate from local isotropy, primarily as a result of anisotropic transfer to the high wavenumbers. To understand the spectral dynamics of this flow we study the detailed behavior of nonlinear triadic interactions in wavenumber space. Spectral transfer in the velocity component parallel to the axis of rotation is qualitatively similar to that in non-rotating turbulence; however the perpendicular component is characterized by a greatly suppressed energy cascade at high wavenumber and a local reverse transfer at the largest scales. The broader implications of this work are briefly addressed.

  19. The effect of external boundary conditions on condensation heat transfer in rotating heat pipes

    NASA Technical Reports Server (NTRS)

    Daniels, T. C.; Williams, R. J.

    1979-01-01

    Experimental evidence shows the importance of external boundary conditions on the overall performance of a rotating heat pipe condenser. Data are presented for the boundary conditions of constant heat flux and constant wall temperature for rotating heat pipes containing either pure vapor or a mixture of vapor and noncondensable gas as working fluid.

  20. Unlocking the talus by eversion limits medial ankle injury risk during external rotation.

    PubMed

    Button, Keith D; Wei, Feng; Haut, Roger C

    2015-10-15

    Eversion prior to excessive external foot rotation has been shown to predispose the anterior tibiofibular ligament (ATiFL) to failure, yet protect the anterior deltoid ligament (ADL) from failure despite high levels of foot rotation. The purpose of the current study was to measure the rotations of both the subtalar and talocrural joints during foot external rotation at sub-failure levels in either a neutral or a pre-everted position as a first step towards understanding the mechanisms of injury in previous studies. Fourteen (seven pairs) cadaver lower extremities were externally rotated 20° in either a pre-everted or neutral configuration, without producing injury. Motion capture was performed to track the tibia, talus, and calcaneus motions, and a joint coordinate system was used to analyze motions of the two joints. While talocrural joint rotation was greater in the neutral ankle (13.3±2.0° versus 10.5±2.7°, p=0.006), subtalar joint rotation was greater in the pre-everted ankle (2.4±1.9° versus 1.1±1.0°, p=0.014). Overall, the talocrural joint rotated more than the subtalar joint (11.9±2.8° versus 1.8±1.6°, p<0.001). It was proposed that the calcaneus and talus 'lock' in a neutral position, but 'unlock' when the ankle is everted prior to rotation. This locking/unlocking mechanism could be responsible for an increased subtalar rotation, but decreased talocrural rotation when the ankle is pre-everted, protecting the ADL from failure. This study may provide information valuable to the study of external rotation kinematics and injury risk.

  1. Reliability of Measurement of Glenohumeral Internal Rotation, External Rotation, and Total Arc of Motion in 3 Test Positions

    PubMed Central

    Kevern, Mark A.; Beecher, Michael; Rao, Smita

    2014-01-01

    Context: Athletes who participate in throwing and racket sports consistently demonstrate adaptive changes in glenohumeral-joint internal and external rotation in the dominant arm. Measurements of these motions have demonstrated excellent intrarater and poor interrater reliability. Objective: To determine intrarater reliability, interrater reliability, and standard error of measurement for shoulder internal rotation, external rotation, and total arc of motion using an inclinometer in 3 testing procedures in National Collegiate Athletic Association Division I baseball and softball athletes. Design: Cross-sectional study. Setting: Athletic department. Patients or Other Participants Thirty-eight players participated in the study. Shoulder internal rotation, external rotation, and total arc of motion were measured by 2 investigators in 3 test positions. The standard supine position was compared with a side-lying test position, as well as a supine test position without examiner overpressure. Results: Excellent intrarater reliability was noted for all 3 test positions and ranges of motion, with intraclass correlation coefficient values ranging from 0.93 to 0.99. Results for interrater reliability were less favorable. Reliability for internal rotation was highest in the side-lying position (0.68) and reliability for external rotation and total arc was highest in the supine-without-overpressure position (0.774 and 0.713, respectively). The supine-with-overpressure position yielded the lowest interrater reliability results in all positions. The side-lying position had the most consistent results, with very little variation among intraclass correlation coefficient values for the various test positions. Conclusions: The results of our study clearly indicate that the side-lying test procedure is of equal or greater value than the traditional supine-with-overpressure method. PMID:25188316

  2. Effects of humeral head compression taping on the isokinetic strength of the shoulder external rotator muscle in patients with rotator cuff tendinitis

    PubMed Central

    Kim, Moon-Hwan; Oh, Jae-Seop

    2015-01-01

    [Purpose] The purpose of this study was to examine the effects of humeral head compression taping (HHCT) on the strength of the shoulder external rotator muscle in patients with rotator cuff tendinitis. [Subjects and Methods] Twenty patients with rotator cuff tendinitis were recruited. The shoulder external rotator strength was measured using a Biodex isokinetic dynamometer system. A paired t-test was performed to evaluate within-group differences in the strength of the shoulder external rotator muscle. [Results] Significantly higher shoulder external rotator peak torque and peak torque per body weight were found in the HHCT condition than in the no-taping condition. [Conclusion] HHCT may effectively increase the shoulder external rotator muscle strength in patients with rotator cuff tendinitis. PMID:25642053

  3. Rotation, differential rotation, and gyrochronology of active Kepler stars

    NASA Astrophysics Data System (ADS)

    Reinhold, Timo; Gizon, Laurent

    2015-11-01

    Context. In addition to the discovery of hundreds of exoplanets, the high-precision photometry from the CoRoT and Kepler satellites has led to measurements of surface rotation periods for tens of thousands of stars, which can potentially be used to infer stellar ages via gyrochronology. Aims: Our main goal is to derive ages of thousands of field stars using consistent rotation period measurements derived by different methods. Multiple rotation periods are interpreted as surface differential rotation (DR). We study the dependence of DR with rotation period and effective temperature. Methods: We reanalyze a previously studied sample of 24 124 Kepler stars using different approaches based on the Lomb-Scargle periodogram. Each quarter (Q1-Q14) is treated individually using a prewhitening approach. Additionally, the full time series and their different segments are analyzed. Results: For more than 18 500 stars our results are consistent with the rotation periods from McQuillan et al. (2014, ApJS, 211, 24). Of these, more than 12 300 stars show multiple significant peaks, which we interpret as DR. Dependencies of the DR with rotation period and effective temperature could be confirmed, e.g., the relative DR increases with rotation period. Gyrochronology ages between 100 Myr and 10 Gyr were derived for more than 17 000 stars using different gyrochronology relations, most of them with uncertainties dominated by period variations. We find a bimodal age distribution for Teff between 3200-4700 K. The derived ages reveal an empirical activity-age relation using photometric variability as stellar activity proxy. Additionally, we found 1079 stars with extremely stable (mostly short) periods. Half of these periods may be associated with rotation stabilized by non-eclipsing companions, the other half might be due to pulsations. Conclusions: The derived gyrochronology ages are well constrained since more than ~93.0% of the stars seem to be younger than the Sun where calibration is

  4. Trapezius muscle transfer for external shoulder rotation: anatomical study

    PubMed Central

    Gracitelli, Mauro Emilio Conforto; Assunção, Jorge Henrique; Malavolta, Eduardo Angeli; Sakane, Daniel Takashi; de Rezende, Marcelo Rosa; Ferreira, Arnaldo Amado

    2014-01-01

    OBJECTIVE: To compare the viability of transferring the lower and transverse trapezius to the greater tuberosity using three different techniques. METHODS: Twelve shoulders from six cadavers were used. The primary outcome was to assess the suture viability of the trapezius muscle transfer to the greater tuberosity in the insertion topography of the infraspinatus, with the arm adducted during internal rotation (hand on the abdomen) and maximum scapular retraction. Three transfers were applied to each shoulder: the lower and transverse trapezius distal insertion (Group 1); lower trapezius alone (Group 2); and lower trapezius insertion and origin (Group 3). Accessory nerve integrity was assessed before and after transfers. RESULTS: Sutures were viable in 42% (5/12) and 58% (7/12) on Groups 1 and 3, respectively, with no statistically significant difference (Fisher's test, p=0.558); Group 3 exhibited frequent neurologic injury (11/12). Group 2 was the least successful; the tendon did not reach the greater tuberosity, and no sutures were viable. CONCLUSION: Groups 1 and 3 exhibited the best nongrafting suture viability to the greater tuberosity; however, Group 3 was associated to frequent spinal accessory nerve injury. Level of Evidence IV, Anatomical Study PMID:25538475

  5. A Kalman filter for feedback control of rotating external kink instabilities in the presence of noise

    SciTech Connect

    Hanson, Jeremy M.; De Bono, Bryan; Levesque, Jeffrey P.; Mauel, Michael E.; Maurer, David A.; Navratil, Gerald A.; Pedersen, Thomas Sunn; Shiraki, Daisuke; James, Royce W.

    2009-05-15

    The simulation and experimental optimization of a Kalman filter feedback control algorithm for n=1 tokamak external kink modes are reported. In order to achieve the highest plasma pressure limits in ITER, resistive wall mode stabilization is required [T. C. Hender et al., Nucl. Fusion 47, S128 (2007)] and feedback algorithms will need to distinguish the mode from noise due to other magnetohydrodynamic activity. The Kalman filter contains an internal model that captures the dynamics of a rotating, growing n=1 mode. This model is actively compared with real-time measurements to produce an optimal estimate for the mode's amplitude and phase. On the High Beta Tokamak-Extended Pulse experiment [T. H. Ivers et al., Phys. Plasmas 3, 1926 (1996)], the Kalman filter algorithm is implemented using a set of digital, field-programmable gate array controllers with 10 {mu}s latencies. Signals from an array of 20 poloidal sensor coils are used to measure the n=1 mode, and the feedback control is applied using 40 poloidally and toroidally localized control coils. The feedback system with the Kalman filter is able to suppress the external kink mode over a broad range of phase angles between the sensed mode and applied control field. Scans of filter parameters show good agreement between simulation and experiment, and feedback suppression and excitation of the kink mode are enhanced in experiments when a filter made using optimal parameters from the scans is used.

  6. Concentric isokinetic shoulder internal and external rotation strength in professional baseball pitchers.

    PubMed

    Ellenbecker, T S; Mattalino, A J

    1997-05-01

    Objective measurement of shoulder internal and external rotation strength is an important part in the comprehensive evaluation and rehabilitation of athletes who perform predominantly unilateral upper extremity movement patterns. Apparatus- and population-specific descriptive data are needed to enhance the interpretation of results from isokinetic dynamometers. The primary purpose of this study was to measure isokinetically glenohumeral joint internal and external rotator peak torque and work in professional baseball pitchers and determine whether significant differences exist between the dominant (throwing) extremity and nondominant extremity. One hundred twenty-five healthy professional baseball pitchers were tested bilaterally on a Cybex 300 series isokinetic dynamometer at 210 and 300 degrees/sec for concentric internal and external rotation of the glenohumeral joint with the arm in 90 degrees of abduction. A standardized protocol and testing guidelines were strictly followed. A dependent t test was used to test for differences between extremities for peak torque and single repetition work isokinetic parameters. No significant difference between the dominant and nondominant shoulder was found for external rotation peak torque or single repetition work at either testing speed. Significantly greater (p < .001) dominant arm shoulder internal rotation was measured for both peak torque and single repetition work at 210 and 300 degrees/sec compared with the nondominant extremity. The results of this study are important for the application and interpretation of isokinetic data on unilaterally dominant upper extremity athletes. The use of a population-specific, descriptive isokinetic data profile is important in both rehabilitation and prevention of shoulder injuries.

  7. Multigrid Computations of 3-D Incompressible Internal and External Viscous Rotating Flows

    NASA Technical Reports Server (NTRS)

    Sheng, Chunhua; Taylor, Lafayette K.; Chen, Jen-Ping; Jiang, Min-Yee; Whitfield, David L.

    1996-01-01

    This report presents multigrid methods for solving the 3-D incompressible viscous rotating flows in a NASA low-speed centrifugal compressor and a marine propeller 4119. Numerical formulations are given in both the rotating reference frame and the absolute frame. Comparisons are made for the accuracy, efficiency, and robustness between the steady-state scheme and the time-accurate scheme for simulating viscous rotating flows for complex internal and external flow applications. Prospects for further increase in efficiency and accuracy of unsteady time-accurate computations are discussed.

  8. Isokinetic profile of shoulder internal and external rotators of high school aged baseball pitchers.

    PubMed

    Mulligan, Ivan J; Biddington, William B; Barnhart, Bruce D; Ellenbecker, Todd S

    2004-11-01

    The purpose of this descriptive study was to determine whether bilateral differences exist in concentric and eccentric shoulder internal and external rotation strength in high school aged baseball pitchers. Thirty-nine high school aged baseball pitchers were bilaterally tested for concentric and eccentric internal and external rotation muscle performance on a Kin-Com 500-H isokinetic dynamometer at 90 degrees .s(-1) and 180 degrees .s(-1). Paired t-tests were used to test for differences among extremities, speed, and ratio of external rotation to internal rotation (ER/IR ratios). Concentric peak torque internal rotation at 90 degrees .s(-1) was significantly greater (p < 0.05) in the dominant arm compared with the nondominant arm. Statistically significant differences (p < 0.001) were found between the nondominant and dominant in concentric 90 degrees .s(-1). The nondominant arm demonstrated significantly greater eccentric strength (p < 0.05) compared with the dominant arm in ER/IR ratios at 90 degrees .s(-1) and 180 degrees .s(-1). The nondominant arm demonstrated significantly greater eccentric strength (p < 0.05) than the dominant arm in ER/IR ratio at 180 degrees .s(-1). Data demonstrated that muscular adaptations are consistent with previous research in this area. Also, muscular adaptations occur in the shoulder in the high school aged population. These data can serve as a guideline to be used by clinicians who rehabilitate shoulders in patients in this population.

  9. The interaction between plasma rotation, stochastic fields and tearing mode excitation by external perturbation fields

    NASA Astrophysics Data System (ADS)

    DeBock, M. F. M.; Classen, I. G. J.; Busch, C.; Jaspers, R. J. E.; Koslowski, H. R.; Unterberg, B.; TEXTOR Team

    2008-01-01

    For fusion reactors, based on the principle of magnetic confinement, it is important to avoid so-called magnetic islands or tearing modes. They reduce confinement and can be the cause of major disruptions. One class of magnetic islands is that of the perturbation field driven modes. This perturbation field can, for example, be the intrinsic error field. Theoretical work predicts a strong relationship between plasma rotation and the excitation of perturbation field modes. Experimentally, the theory on mode excitation and plasma rotation has been confirmed on several tokamaks. In those experiments, however, the control over the plasma rotation velocity and direction, and over the externally applied perturbation field was limited. In this paper experiments are presented that were carried out at the TEXTOR tokamak. Two tangential neutral beam injectors and a set of helical perturbation coils, called the dynamic ergodic divertor (DED), provide control over both the plasma rotation and the external perturbation field in TEXTOR. This made it possible to set up a series of experiments to test the theory on mode excitation and plasma rotation in detail. The perturbation field induced by the DED not only excites magnetic islands, it also sets up a layer near the plasma boundary where the magnetic field is stochastic. It will be shown that this stochastic field alters both the rotational response of the plasma on the perturbation field and the threshold for mode excitation. It therefore has to be included in an extended theory on mode excitation.

  10. The strength characteristics of internal and external rotator muscles in professional baseball pitchers.

    PubMed

    Wilk, K E; Andrews, J R; Arrigo, C A; Keirns, M A; Erber, D J

    1993-01-01

    The purpose of this study was to establish a data base regarding the isokinetic muscular performance characteristics of the external/internal rotator muscles of professional baseball pitchers. One hundred fifty healthy professional baseball pitchers were evaluated by use of a Biodex isokinetic dynamometer. The subjects tested had a mean age of 23.4 years and a mean body weight of 199 pounds. Isokinetic tests were performed concentrically at 180 and 300 deg/sec for both the throwing and nonthrowing shoulders. Testing procedures regarding positioning and stabilization followed established guidelines. The testing protocol and actual test repetitions were standardized for each subject. Statistical analysis was performed using the Pearson Product Moment Correlation and paired t-tests. Determination of the correlation coefficient was made at the P < 0.05 level of significance. Test results for bilateral comparison of mean peak torque for the throwing and nonthrowing shoulders indicated no statistically significant difference between the internal rotators at both test speeds, or for the external rotators at 300 deg/sec. There was a significant statistical difference at the 180 deg/sec test speed for the external rotators. The external/internal rotator strength ratio indicated a 65% ratio at 180 deg/sec and a 61% ratio at 300 deg/sec. Data were also collected for mean peak torque/body weight ratios of the throwing shoulder to establish a data base in professional throwers. This study offers clinical relevance in establishing a muscle performance profile for the professional thrower. This data base can therefore be used as criteria that should be met before an injured pitcher can be returned to throwing at the professional baseball level.

  11. A NEW CLINICAL MUSCLE FUNCTION TEST FOR ASSESSMENT OF HIP EXTERNAL ROTATION STRENGTH: AUGUSTSSON STRENGTH TEST

    PubMed Central

    2016-01-01

    ABSTRACT Introduction Dynamic clinical tests of hip strength applicable on patients, non–athletes and athletes alike, are lacking. The aim of this study was therefore to develop and evaluate the reliability of a dynamic muscle function test of hip external rotation strength, using a novel device. A second aim was to determine if gender differences exist in absolute and relative hip strength using the new test. Methods Fifty–three healthy sport science students (34 women and 19 men) were tested for hip external rotation strength using a device that consisted of a strap connected in series with an elastic resistance band loop, and a measuring tape connected in parallel with the elastic resistance band. The test was carried out with the subject side lying, positioned in 45 ° of hip flexion and the knees flexed to 90 ° with the device firmly fastened proximally across the knees. The subject then exerted maximal concentric hip external rotation force against the device thereby extending the elastic resistance band. The displacement achieved by the subject was documented by the tape measure and the corresponding force production was calculated. Both right and left hip strength was measured. Fifteen of the subjects were tested on repeated occasions to evaluate test–retest reliability. Results No significant test–retest differences were observed. Intra–class correlation coefficients ranged 0.93–0.94 and coefficients of variation 2.76–4.60%. In absolute values, men were significantly stronger in hip external rotation than women (right side 13.2 vs 11.0 kg, p = 0.001, left side 13.2 vs 11.5 kg, p = 0.002). There were no significant differences in hip external rotation strength normalized for body weight (BW) between men and women (right side 0.17 kg/BW vs 0.17 kg/BW, p = 0.675, left side 0.17 kg/BW vs 0.18 kg/BW, p = 0.156). Conclusions The new muscle function test showed high reliability and thus could be useful for measuring dynamic hip

  12. Measuring Eccentric Strength of the Shoulder External Rotators Using a Handheld Dynamometer: Reliability and Validity

    PubMed Central

    Johansson, Fredrik R.; Skillgate, Eva; Lapauw, Mattis L.; Clijmans, Dorien; Deneulin, Valentijn P.; Palmans, Tanneke; Engineer, Human Kinetic; Cools, Ann M.

    2015-01-01

    Context Shoulder strength assessment plays an important role in the clinical examination of the shoulder region. Eccentric strength measurements are of special importance in guiding the clinician in injury prevention or return-to-play decisions after injury. Objective To examine the absolute and relative reliability and validity of a standardized eccentric strength-measurement protocol for the glenohumeral external rotators. Design Descriptive laboratory study. Setting Testing environment at the Department of Rehabilitation Sciences and Physiotherapy of Ghent University, Belgium. Patients or Other Participants Twenty-five healthy participants (9 men and 16 women) without any history of shoulder pain were tested by 2 independent assessors using a handheld dynamometer (HHD) and underwent an isokinetic testing procedure. Intervention(s) The clinical protocol used an HHD, a DynaPort accelerometer to measure acceleration and angular velocity of testing 30°/s over 90° of range of motion, and a Biodex dynamometer to measure isokinetic activity. Main Outcome Measure(s) Three eccentric strength measurements: (1) tester 1 with the HHD, (2) tester 2 with the HHD, and (3) Biodex isokinetic strength measurement. Results The intratester reliability was excellent (0.879 and 0.858), whereas the intertester reliability was good, with an intraclass correlation coefficient between testers of 0.714. Pearson product moment correlation coefficients of 0.78 and 0.70 were noted between the HHD and the isokinetic data, showing good validity of this new procedure. Conclusions Standardized eccentric rotator cuff strength can be tested and measured in the clinical setting with good-to-excellent reliability and validity using an HHD. PMID:25974381

  13. Patellofemoral pain in female ballet dancers: correlation with iliotibial band tightness and tibial external rotation.

    PubMed

    Winslow, J; Yoder, E

    1995-07-01

    Review of the literature reveals that ballet dancers have a high incidence of idiopathic patellofemoral pain. Twenty-four female ballet dancers were subjects in a study of the relationship between: 1) iliotibial band (ITB) tightness and patellofemoral pain, and 2) ITB tightness and degrees of tibial external rotation used in the dance demi-plie. Dancers were initially assessed by questionnaire to determine if any had knee pain. Twelve subjects met the study criteria for patellofemoral pain, and 12 dancers without knee pain served as controls for the study, Iliotibial band tightness was measured (Ober test), and degrees of tibial external rotation used during knee flexion (demi-plie) in standing were measured in both legs of all 24 subjects (48 legs). Chi-square analysis of the collected data revealed that there was an association between ITB tightness and patellofemoral pain in the dancers. Data analysis using the Wilcoxon Rank Sum test revealed that the degree of tibial external rotation used by dancers with iliotibial band tightness was significantly greater than those without ITB tightness. This study confirms the assumption that ITB tightness in dancers may be a contributing factor to patellofemoral pain. Follow-up study is indicated to determine if the preservation or restoration of functional ITB length is effective in the prevention and/or treatment of patellofemoral pain in ballet dancers. PMID:7550298

  14. Study on a magnetic spiral-type wireless capsule endoscope controlled by rotational external permanent magnet

    NASA Astrophysics Data System (ADS)

    Ye, Bo; Zhang, Wei; Sun, Zhen-jun; Guo, Lin; Deng, Chao; Chen, Ya-qi; Zhang, Hong-hai; Liu, Sheng

    2015-12-01

    In this paper, the authors propose rotating an external permanent magnet (EPM) to manipulate the synchronous rotation of a magnetic spiral-type wireless capsule endoscope (WCE), and the synchronous rotation of the WCE is converted to its translational motion in intestinal tract. In order to preliminarily verify the feasibility of this method, a handheld actuator (HA) controlled by micro controller unit, a magnetic spiral-type WCE and a bracket were fabricated, theoretical analysis and simulations about the control distance of this method were performed, and in ex-vivo tests were examined in porcine small intestine to verify the control distance and control performances of this method. It was demonstrated that this method showed good performances in controlling the translational motion of the magnetic spiral-type WCE, and this method has great potential to be used in clinical application.

  15. Electromyographic Analysis of the Shoulder Girdle Musculature During External Rotation Exercises

    PubMed Central

    Alizadehkhaiyat, Omid; Hawkes, David H.; Kemp, Graham J.; Frostick, Simon P.

    2015-01-01

    Background: Implementation of overhead activity, a key component of many professional sports, requires an effective and balanced activation of the shoulder girdle muscles, particularly during forceful external rotation (ER) motions. Purpose: To identify activation strategies of 16 shoulder girdle muscles/muscle segments during common shoulder ER exercises. Study Design: Descriptive laboratory study. Method: Thirty healthy subjects were included in this study, and 16 shoulder girdle muscles/muscle segments were investigated (surface electrode: anterior, middle, and posterior deltoid; upper, middle, and lower trapezius; serratus anterior; teres major; upper and lower latissimus dorsi; and upper and lower pectoralis major; fine wire electrodes: supraspinatus, infraspinatus, subscapularis, and rhomboid major) using a telemetric electromyography (EMG) system. Five ER exercises (standing ER at 0° and 90° of abduction, with underarm towel roll, prone ER at 90° of abduction, side-lying ER with underarm towel) were studied. Exercise EMG amplitudes were normalized to EMG at maximum ER force in a standard position. Univariate analysis of variance and post hoc analysis applied on EMG activity of each muscle were used to assess the main effect of the exercise condition. Results: Muscular activity differed significantly among the ER exercises (P < .05 to P < .001). The greatest activation for anterior and middle deltoid, supraspinatus, upper trapezius, and serratus anterior occurred during standing ER at 90° of abduction; for posterior deltoid, middle trapezius, and rhomboid during side-lying ER with underarm towel; for lower trapezius, upper and lower latissimus dorsi, subscapularis, and teres major during prone ER at 90° of abduction; and for the clavicular and sternal part of the pectoralis major during standing ER with underarm towel. Conclusion: Key glenohumeral and scapular muscles can be optimally activated during specific ER exercises, particularly in positions that

  16. Gyrokinetic simulations with external resonant magnetic perturbations: Island torque and nonambipolar transport with plasma rotation

    NASA Astrophysics Data System (ADS)

    Waltz, R. E.; Waelbroeck, F. L.

    2012-03-01

    Static external resonant magnetic field perturbations (RMPs) have been added to the gyrokinetic code GYRO [J. Candy and R. E. Waltz, J. Comp. Phys. 186, 545 (2003)]. This allows nonlinear gyrokinetic simulations of the nonambipolar radial current flow jr, and the corresponding j→×B→ plasma torque (density) R[jrBp/c], induced by magnetic islands that break the toroidal symmetry of a tokamak. This extends the previous GYRO formulation for the transport of toroidal angular momentum (TAM) [R. E. Waltz, G. M. Staebler, J. Candy, and F. L. Hinton, Phys. Plasmas 14, 122507 (2007); errata 16, 079902 (2009)]. The focus is on electrostatic full torus radial slice simulations of externally induced q =m/n=6/3 islands with widths 5% of the minor radius or about 20 ion gyroradii. Up to moderately strong E ×B rotation, the island torque scales with the radial electric field at the resonant surface Er, the island width w, and the intensity I of the high-n micro-turbulence, as Erw√I . The radial current inside the island is carried (entirely in the n =3 component) and almost entirely by the ion E ×B flux, since the electron E ×B and magnetic flutter particle fluxes are cancelled. The net island torque is null at zero Er rather than at zero toroidal rotation. This means that while the expected magnetic braking of the toroidal plasma rotation occurs at strong co- and counter-current rotation, at null toroidal rotation, there is a small co-directed magnetic acceleration up to the small diamagnetic (ion pressure gradient driven) co-rotation corresponding to the zero Er and null torque. This could be called the residual stress from an externally induced island. At zero Er, the only effect is the expected partial flattening of the electron temperature gradient within the island. Finite-beta GYRO simulations demonstrate almost complete RMP field screening and n =3 mode unlocking at strong Er.

  17. The role of shoulder maximum external rotation during throwing for elbow injury prevention in baseball players.

    PubMed

    Miyashita, Koji; Urabe, Yukio; Kobayashi, Hirokazu; Yokoe, Kiyoshi; Koshida, Sentaro; Kawamura, Morio; Ida, Kunio

    2008-01-01

    The objective of the present study was to examine whether the passive range of shoulder external rotation (ER), the maximum shoulder external rotation angle (MER) during throwing, and the ratio of MER to ER are related to the incidence of the elbow injury. A mixed design with one between-factor (a history of the elbow injury) and two within-factors (ER and MER) was used to analyze the difference between baseball players with and without a history of medial elbow pain. Twenty high school baseball players who had experienced the medial elbow pain within the previous month but who were not experiencing the pain on the day of the experiment were recruited (elbow-injured group). Another twenty baseball players who had never experienced the medial elbow pain were also used for testing (control group). MER during throwing, ER, and the ratio of MER to ER were obtained in both of the group. A Mann-Whitney test was used for the group comparison (p < 0.05). The ratio of MER to ER was significantly greater in the elbow-injured group (1.52 ± 0.19) than that in the control group (1.33 ± 0.23) (p = 0.008). On the other hand, there was no statistical significance in MER and ER between two groups. The findings of the study indicate that MER/ER relation could be associated with the incidence of the elbow injury in baseball players. Key pointsIt is accepted that the greatest elbow valgus stress appears at the position of shoulder maximum external rotation (MER) in the acceleration phase of the throwing movement. As a consequence, shoulders with restricted range of motion of external rotation (ER) compensate with a valgus stress on their elbow joints.In this study, we evaluated the relation between MER and ER of shoulder in players with/without elbow injuries.The result of this study demonstrated that the elbow injured group showed significantly greater MER/ER relation than the control group.The current finding suggests that great MER combined with the ROM restriction may be one of

  18. Kilovoltage Rotational External Beam Radiotherapy on a Breast Computed Tomography Platform: A Feasibility Study

    SciTech Connect

    Prionas, Nicolas D.; McKenney, Sarah E.; Stern, Robin L.; Boone, John M.

    2012-10-01

    Purpose: To demonstrate the feasibility of a dedicated breast computed tomography (bCT) platform to deliver rotational kilovoltage (kV) external beam radiotherapy (RT) for partial breast irradiation, whole breast irradiation, and dose painting. Methods and Materials: Rotational kV-external beam RT using the geometry of a prototype bCT platform was evaluated using a Monte Carlo simulator. A point source emitting 178 keV photons (approximating a 320-kVp spectrum with 4-mm copper filtration) was rotated around a 14-cm voxelized polyethylene disk (0.1 cm tall) or cylinder (9 cm tall) to simulate primary and primary plus scattered photon interactions, respectively. Simulations were also performed using voxelized bCT patient images. Beam collimation was varied in the x-y plane (1-14 cm) and in the z-direction (0.1-10 cm). Dose painting for multiple foci, line, and ring distributions was demonstrated using multiple rotations with varying beam collimation. Simulations using the scanner's native hardware (120 kVp filtered by 0.2-mm copper) were validated experimentally. Results: As the x-y collimator was narrowed, the two-dimensional dose profiles shifted from a cupped profile with a high edge dose to an increasingly peaked central dose distribution with a sharp dose falloff. Using a 1-cm beam, the cylinder edge dose was <7% of the dose deposition at the cylinder center. Simulations using 120-kVp X-rays showed distributions similar to the experimental measurements. A homogeneous dose distribution (<2.5% dose fluctuation) with a 20% decrease in dose deposition at the cylinder edge (i.e., skin sparing) was demonstrated by weighted summation of four dose profiles using different collimation widths. Simulations using patient bCT images demonstrated the potential for treatment planning and image-guided RT. Conclusions: Rotational kV-external beam RT for partial breast irradiation, dose painting, and whole breast irradiation with skin sparing is feasible on a bCT platform with

  19. Relationship between maximum shoulder external rotation angle during throwing and physical variables.

    PubMed

    Miyashita, Koji; Urabe, Yukio; Kobayashi, Hirokazu; Yokoe, Kiyoshi; Koshida, Sentaro; Kawamura, Morio; Ida, Kunio

    2008-01-01

    The amount of stress imposed on shoulder and elbow appears to be directly correlated with the degree of maximum shoulder external rotation (MER) during throwing motions. Therefore, identifying risk factors contributing to the increase of MER angle may help to decrease the throwing injuries occurrence in baseball players. The purpose of the present study was to demonstrate the correlation between MER and the kinematic variables at stride foot contact (SFC) during the early cocking phase, the passive range of motion (ROM), and the shoulder strength. The subjects were 40 high school baseball players. Each subject carried out five throwing tasks with his maximum effort. A three-dimensional analysis was performed to obtain the MER, and the shoulder angles of external rotation (ER), extension and abduction at SFC in the early cocking phase. The ROM and muscle strength of the shoulder ER and internal rotation (IR) were also measured. Significant moderate linear correlations were found between the MER and the ER (r = -0.32, p = 0.04) at SFC, extension angle ( r= 0.35, p = 0.03) at SFC, IR strength (r = -0.30, p = 0.04) and passive ROM of ER (r = 0.46, p = 0.01). The shoulder IR and extension angles at SFC may determine the degree of the MER angle. Furthermore, weak IR muscle strength and excessive ROM of ER might be risk factors for shoulder and elbow injuries. The finding will enable us to establish better prevention and rehabilitation strategies for throwing injuries in baseball players. Key pointsIt has been reported that the amount of stress imposed on shoulder and elbow joints is correlated with the degree of maximum shoulder external rotation angle (MER) during throwing. Therefore, controlling MER within a normal range plays a key role in the prevention for throwing-related injuries in baseball players.Physical and biomechanical factors related to the degree of MER must be addressed to advance the current prevention and rehabilitation strategies for the shoulder and

  20. On the stellar rotation-activity connection

    NASA Technical Reports Server (NTRS)

    Rosner, R.

    1983-01-01

    The relationship between rotation rates and surface activity in late-type dwarf stars is explored in a survey of recent theoretical and observational studies. Current theoretical models of stellar-magnetic-field production and coronal activity are examined, including linear kinematic dynamo theory, nonlinear dynamos using approximations, and full numerical simulations of the MHD equations; and some typical results are presented graphically. The limitations of the modeling procedures and the constraints imposed by the physics are indicated. The statistical techniques used in establishing correlations between various observational parameters are analyzed critically, and the methods developed for quasar luminosity functions by Avni et al. (1980) are used to evaluate the effects of upper detection bounds, incomplete samples, and missing data for the case of rotation and X-ray flux data.

  1. Rotating bacteria aggregate into active crystals

    NASA Astrophysics Data System (ADS)

    Petroff, Alexander; Wu, Xiao-Lun; Libchaber, Albert

    2014-11-01

    The dynamics of many microbial ecosystems are determined not only by the response of individual bacteria to their chemical and physical environments but also the dynamics that emerge from interactions between cells. Here we investigate the collective dynamics displayed by communities of Thiovulum majus, one of the fastest known bacteria. We observe that when these bacteria swim close to a microscope cover slip, the cells spontaneously aggregate into a visually-striking two-dimensional hexagonal lattice of rotating cells. Each cell in an aggregate rotates its flagella, exerting a force that pushes the cell into the cover slip and a torque that causes the cell to rotate. As cells rotate against their neighbors, they exert forces and torques on the aggregate that cause the crystal to move and cells to hop to new positions in the lattice. We show how these dynamics arises from hydrodynamic and surface forces between cells. We derive the equations of motion for an aggregate, show that this model reproduces many aspects of the observed dynamics, and discuss the stability of these and similar active crystals. Finally, we discuss the ecological significance of this behavior to understand how the ability to aggregate into these communities may have evolved.

  2. Rotating Bacteria Aggregate into Active Crystals

    NASA Astrophysics Data System (ADS)

    Petroff, A. P.; Wu, X. L.; Libchaber, A.

    2014-12-01

    The dynamics of many microbial ecosystems are determined not only by the response of individual bacteria to their chemical and physical environments but also the dynamics that emerge from interactions between cells. Here we investigate collective dynamics displayed by communities of Thiovulum majus, one of the fastest known bacteria. We observe that when these bacteria swim close to a microscope cover slip, the cells spontaneously aggregate into a visually-striking, two-dimensional hexagonal lattice of rotating cells. Each cell in an aggregate rotates its flagella, exerting a force that pushes the cell into the cover slip and a torque that causes the cell to rotate. As cells rotate against their neighbors, they exert forces and torques on the aggregate that cause the crystal to move and cells to hop to new positions in the lattice. We show how these dynamics arise from hydrodynamic and surface forces between cells. We derive the equations of motion for an aggregate, show that this model reproduces many aspects of the observed dynamics, and discuss the stability of these and similar active crystals. Finally, we discuss the ecological significance of this behavior to understand how the ability to aggregate into these communities may have evolved.

  3. External rotation views in the diagnosis of posterior colliculus fracture of the medial malleolus.

    PubMed

    Ebraheim, N A; Wong, F Y

    1996-05-01

    A 25-year-old white man sustained a fracture dislocation of the right ankle with a displaced fracture of the lateral malleolus while playing basketball. He also sustained a fracture of the medial aspect of the distal tibia, in addition to an apparent deltoid ligament injury. The patient underwent open reduction and internal fixation of the lateral malleolus and insertion of a syndesmotic screw. Intraoperatively, external rotation radiographs of the ankle were obtained to determine the origin of the fracture of the medial side of the ankle joint. The radiographs clearly showed a minimally displaced fracture of the posterior colliculus. Posterior colliculus fracture can be occult. This fracture may not be clearly visible on plain antero-posterior or mortise-view radiographs and external rotation is necessary for its diagnosis. This fracture is usually minimally displaced and can be satisfactorily treated conservatively. The patient's leg was placed in a short-leg cast for 6 weeks. Follow-up radiographs revealed healing of the fracture.

  4. Internal and external components of the bacterial flagellar motor rotate as a unit.

    PubMed

    Hosu, Basarab G; Nathan, Vedavalli S J; Berg, Howard C

    2016-04-26

    Most bacteria that swim, including Escherichia coli, are propelled by helical filaments, each driven at its base by a rotary motor powered by a proton or a sodium ion electrochemical gradient. Each motor contains a number of stator complexes, comprising 4MotA 2MotB or 4PomA 2PomB, proteins anchored to the rigid peptidoglycan layer of the cell wall. These proteins exert torque on a rotor that spans the inner membrane. A shaft connected to the rotor passes through the peptidoglycan and the outer membrane through bushings, the P and L rings, connecting to the filament by a flexible coupling known as the hook. Although the external components, the hook and the filament, are known to rotate, having been tethered to glass or marked by latex beads, the rotation of the internal components has remained only a reasonable assumption. Here, by using polarized light to bleach and probe an internal YFP-FliN fusion, we show that the innermost components of the cytoplasmic ring rotate at a rate similar to that of the hook.

  5. Faraday rotation spectroscopy of nitrogen dioxide based on a widely tunable external cavity quantum cascade laser

    NASA Astrophysics Data System (ADS)

    Zaugg, Christian A.; Lewicki, Rafal; Day, Tim; Curl, Robert F.; Tittel, Frank K.

    2011-01-01

    Faraday Rotation Spectroscopy (FRS) is a technique for the sensitive and selective detection of paramagnetic molecules or radicals such as NO, NO2, O2 or OH-. Moreover FRS is suitable for atmospheric measurements due to the insensitivity to non-paramagnetic interfering molecules such as H2O and CO2. Experimental results of an FRS sensor for the NO2detection employing an external-cavity quantum cascade laser (EC-QCL) are reported. The CW EC-QCL exhibits modehop free (MHF) tuning between 1600 cm-1 and 1650 cm-1. This allows targeting the optimum 441<--440 Q-branch NO2transition at 1613.25 cm-1. A rotation of the polarization state of the initially linearly polarized laser light is observed when an AC magnetic field is applied to the NO2 cell, placed between two nearly crossed Rochon polarizers. This rotation of the polarization state is proportional to the NO2 concentration and can be determined by a photodetector located after the second polarizer. For long-term continuous measurements a second branch consisting of a detector and reference cell filled with 0.2 % NO2 in N2 is used to lock the laser to the selected NO2 transition. A minimum detection sensitivity (1σ) of 1 parts per billion (ppbv) was obtained for a 1 sec lock-in time constant (TC).

  6. Internal and external components of the bacterial flagellar motor rotate as a unit

    PubMed Central

    Hosu, Basarab G.; Nathan, Vedavalli S. J.; Berg, Howard C.

    2016-01-01

    Most bacteria that swim, including Escherichia coli, are propelled by helical filaments, each driven at its base by a rotary motor powered by a proton or a sodium ion electrochemical gradient. Each motor contains a number of stator complexes, comprising 4MotA 2MotB or 4PomA 2PomB, proteins anchored to the rigid peptidoglycan layer of the cell wall. These proteins exert torque on a rotor that spans the inner membrane. A shaft connected to the rotor passes through the peptidoglycan and the outer membrane through bushings, the P and L rings, connecting to the filament by a flexible coupling known as the hook. Although the external components, the hook and the filament, are known to rotate, having been tethered to glass or marked by latex beads, the rotation of the internal components has remained only a reasonable assumption. Here, by using polarized light to bleach and probe an internal YFP-FliN fusion, we show that the innermost components of the cytoplasmic ring rotate at a rate similar to that of the hook. PMID:27071081

  7. Proxima Centauri: Rotation, Chromosperic Activity, and Flares

    NASA Astrophysics Data System (ADS)

    Guinan, E. F.; Morgan, N. D.

    1996-05-01

    At a distance of 4.3 LY, Proxima Centauri (= Alpha Cen C; V645 Cen) is the nearest known star to the Sun. This M5 V flare star is the faintest member of the Alpha Cen triple star system (or moving group) and lies about 1400 AU nearer to the Earth than its brighter G2 V and K2 V companions. Because of its proximity and its membership in the triple system, Proxima has well determined physical properties that includes an age of 5-6 Gyr. In spite of its old age, Proxima is a chromospherically active star with strong Mg II h+k (280nm) emission as well as being a flare star. This star is of great importance to magnetic dynamo theory because it is expected to have a fully convective envelope. One quantity, not well determined yet vital to understanding Proxima's magnetic behavior, is its rotation period. During May-August 1995, Proxima was observed about twice a week with the IUE Satellite. Low resolution LWP (200-320nm) spectra were obtained chiefly to observe the chromospheric Mg II emission and use it to measure Proxima's rotation period as active plage regions on the star's surface rotate in and out of view. The IUE data have been analyzed and the Mg II emission shows 20-25% variations with a period of 31.5+/-1.5 days. This period is assumed to be the star's rotation period. In addition, several flare events were observed and evidence was found for rather fast changes (on a time-scale of weeks) in the plage activity and distribution. Also, comparison of the 1995 data with earlier IUE archival data shows that Proxima probably has an activity cycle and that during 1995 it was near a minimum of activity. Nonetheless, 4 flares were detected. We will present the results of the IUE study and also compare the rotation determination with previous attempts such as that of Benedict et al. (1994). This study is supported from NASA grant NAG 5-2160 and NSF grant AST-9315365, which we gratefully acknowledge.

  8. Upper extremity range of motion and isokinetic strength of the internal and external shoulder rotators in major league baseball players.

    PubMed

    Brown, L P; Niehues, S L; Harrah, A; Yavorsky, P; Hirshman, H P

    1988-01-01

    Forty-one professional baseball players volunteered for upper extremity range of motion measurements and isokinetic testing for internal and external shoulder rotation. Pitchers demonstrated 9 degrees more external shoulder rotation with the arm abducted, 5 degrees more forearm pronation, and 9 degrees less shoulder extension on the dominant side compared with the dominant side of position players. Pitchers also demonstrated 9 degrees more external rotation in abduction, 5 degrees less shoulder flexion, 11 degrees less horizontal extension, 15 degrees less internal rotation in abduction, 6 degrees less elbow extension, 4 degrees less elbow flexion, and 5 degrees less forearm supination on the dominant side compared with their nondominant side. Position players demonstrated 8 degrees more external rotation in abduction, 14 degrees less horizontal extension, and 8 degrees less elbow extension on the dominant side compared with their nondominant side. Greater torque was produced by pitchers compared with position players for the dominant and nondominant arm at all test speeds for both mean peak and mean average torque. Greater torque was produced by the dominant arm compared with the nondominant arm also at all test speeds for both of these measurements. No difference was found between the rotation ratios for either arm, for either group, for all speeds.

  9. The variability in the external rotation axis of the distal femur: an MRI-based anatomical study.

    PubMed

    Jones, Carl; Nawaz, Zuhair; Hassan, Abdel; White, Simon; Khaleel, Arshad

    2016-02-01

    Commonly used total knee arthroplasty (TKA) systems utilising measured resection techniques default to 5°-7° valgus for the distal cut relative to the anatomical axis and 3° external rotation of the femoral component relative to posterior condylar axis (PCA). Rotational errors of the femoral component are associated with pain, patella maltracking and a poorer outcome. We analysed MRI scans from patients undergoing TKA using patient-specific instrumentation to assess coronal and rotational alignment from landmarks identified on the scans. One hundred and eight scans in 59 males and 49 females were studied with age range 35-93 years (mean 67.9 years). We found 91 % of patients had a femoral valgus angle between 5° and 7° (mean angles 5.9°), while only 24 % had an external rotation angle between 2.5° and 3.5° relative to PCA. There was no statistical significance in rotation between males and females although outliers tended to be female. Mean Whiteside's angle was 92.9° (87.8-98). This study highlights the variations in external rotation between patients undergoing TKA using the PCA as a reference for rotation. This may be a contributing factor in implant malalignment and patient dissatisfaction.

  10. Shielding of External Magnetic Perturbations By Torque In Rotating Tokamak Plasmas

    SciTech Connect

    Park, Jong-Kyu; Boozer, Allen H.; Menard, Jonathan E.; Gerhardt, Stefan P.; Sabbagh, Steve A.

    2009-08-24

    The imposition of a nonaxisymmetric magnetic perturbation on a rotating tokamak plasma requires energy and toroidal torque. Fundamental electrodynamics implies that the torque is essentially limited and must be consistent with the external response of a plasma equilibrium ƒ = j x B. Here magnetic measurements on National Spherical Torus eXperiment (NSTX) device are used to derive the energy and the torque, and these empirical evaluations are compared with theoretical calculations based on perturbed scalar pressure equilibria ƒ = ∇p coupled with the theory of nonambipolar transport. The measurement and the theory are consistent within acceptable uncertainties, but can be largely inconsistent when the torque is comparable to the energy. This is expected since the currents associated with the torque are ignored in scalar pressure equilibria, but these currents tend to shield the perturbation.

  11. Long-term outcome after supination-external rotation type-4 fractures of the ankle.

    PubMed

    Stufkens, S A S; Knupp, M; Lampert, C; van Dijk, C N; Hintermann, B

    2009-12-01

    We have compared the results at a mean follow-up of 13 years (11 to 14) of two groups of supination-external rotation type-4 fractures of the ankle, in one of which there was a fracture of the medial malleolus and in the other the medial deltoid ligament had been partially or completely ruptured. Of 66 patients treated operatively between 1993 and 1997, 36 were available for follow-up. Arthroscopy had been performed in all patients pre-operatively to assess the extent of the intra-articular lesions. The American Orthopaedic Foot and Ankle Society hind-foot score was used for clinical evaluation and showed a significant difference in both the total and the functional scores (p < 0.05), but not in those for pain or alignment, in favour of the group with a damaged deltoid ligament (p < 0.05). The only significant difference between the groups on the short-form 36 quality-of-life score was for bodily pain, again in favour of the group with a damaged deltoid ligament. There was no significant difference between the groups in the subjective visual analogue scores or in the modified Kannus radiological score. Arthroscopically, there was a significant difference with an increased risk of loose bodies in the group with an intact deltoid ligament (p < 0.005), although there was no significant increased risk of deep cartilage lesions in the two groups. At a mean follow-up of 13 years after operative treatment of a supination-external rotation type-4 ankle fracture patients with partial or complete rupture of the medial deltoid ligament tended to have a better result than those with a medial malleolar fracture.

  12. A method for the estimate of the wall diffusion for non-axisymmetric fields using rotating external fields

    NASA Astrophysics Data System (ADS)

    Frassinetti, L.; Olofsson, K. E. J.; Fridström, R.; Setiadi, A. C.; Brunsell, P. R.; Volpe, F. A.; Drake, J.

    2013-08-01

    A new method for the estimate of the wall diffusion time of non-axisymmetric fields is developed. The method based on rotating external fields and on the measurement of the wall frequency response is developed and tested in EXTRAP T2R. The method allows the experimental estimate of the wall diffusion time for each Fourier harmonic and the estimate of the wall diffusion toroidal asymmetries. The method intrinsically considers the effects of three-dimensional structures and of the shell gaps. Far from the gaps, experimental results are in good agreement with the diffusion time estimated with a simple cylindrical model that assumes a homogeneous wall. The method is also applied with non-standard configurations of the coil array, in order to mimic tokamak-relevant settings with a partial wall coverage and active coils of large toroidal extent. The comparison with the full coverage results shows good agreement if the effects of the relevant sidebands are considered.

  13. Humeral external rotation handling by using the Bobath concept approach affects trunk extensor muscles electromyography in children with cerebral palsy.

    PubMed

    Grazziotin Dos Santos, C; Pagnussat, Aline S; Simon, A S; Py, Rodrigo; Pinho, Alexandre Severo do; Wagner, Mário B

    2014-10-20

    This study aimed to investigate the electromyographic activity of cervical and trunk extensors muscles in children with cerebral palsy during two handlings according to the Bobath concept. A crossover trial involving 40 spastic diplegic children was conducted. Electromyography (EMG) was used to measure muscular activity at sitting position (SP), during shoulder internal rotation (IR) and shoulder external rotation (ER) handlings, which were performed using the elbow joint as key point of control. Muscle recordings were performed at the fourth cervical (C4) and at the tenth thoracic (T10) vertebral levels. The Gross Motor Function Classification System (GMFCS) was used to assess whether muscle activity would vary according to different levels of severity. Humeral ER handling induced an increase on EMG signal of trunk extensor muscles at the C4 (P=0.007) and T10 (P<0.001) vertebral levels. No significant effects were observed between SP and humeral IR handling at C4 level; However at T10 region, humeral IR handling induced an increase of EMG signal (P=0.019). Humeral ER resulted in an increase of EMG signal at both levels, suggesting increase of extensor muscle activation. Furthermore, the humeral ER handling caused different responses on EMG signal at T10 vertebra level, according to the GMFCS classification (P=0.017). In summary, an increase of EMG signal was observed during ER handling in both evaluated levels, suggesting an increase of muscle activation. These results indicate that humeral ER handling can be used for diplegic CP children rehabilitation to facilitate cervical and trunk extensor muscles activity in a GMFCS level-dependent manner. PMID:25462474

  14. Optimal rotation sequences for active perception

    NASA Astrophysics Data System (ADS)

    Nakath, David; Rachuy, Carsten; Clemens, Joachim; Schill, Kerstin

    2016-05-01

    One major objective of autonomous systems navigating in dynamic environments is gathering information needed for self localization, decision making, and path planning. To account for this, such systems are usually equipped with multiple types of sensors. As these sensors often have a limited field of view and a fixed orientation, the task of active perception breaks down to the problem of calculating alignment sequences which maximize the information gain regarding expected measurements. Action sequences that rotate the system according to the calculated optimal patterns then have to be generated. In this paper we present an approach for calculating these sequences for an autonomous system equipped with multiple sensors. We use a particle filter for multi- sensor fusion and state estimation. The planning task is modeled as a Markov decision process (MDP), where the system decides in each step, what actions to perform next. The optimal control policy, which provides the best action depending on the current estimated state, maximizes the expected cumulative reward. The latter is computed from the expected information gain of all sensors over time using value iteration. The algorithm is applied to a manifold representation of the joint space of rotation and time. We show the performance of the approach in a spacecraft navigation scenario where the information gain is changing over time, caused by the dynamic environment and the continuous movement of the spacecraft

  15. Hip External Rotator Strength Is Associated With Better Dynamic Control of the Lower Extremity During Landing Tasks.

    PubMed

    Malloy, Philip J; Morgan, Alexander M; Meinerz, Carolyn M; Geiser, Christopher F; Kipp, Kristof

    2016-01-01

    The purpose of this study was to determine the association between hip strength and lower extremity kinematics and kinetics during unanticipated single-leg landing and cutting tasks in collegiate female soccer players. Twenty-three National Collegiate Athletic Association division I female soccer players were recruited for strength testing and biomechanical analysis. Maximal isometric hip abduction and external rotation strength were measured using a hand-held dynamometer and expressed as muscle torque (force × femoral length) and normalized to body weight. Three-dimensional lower extremity kinematics and kinetics were assessed with motion analysis and force plates, and an inverse dynamics approach was used to calculate net internal joint moments that were normalized to body weight. Greater hip external rotator strength was significantly associated with greater peak hip external rotation moments (r = 0.47; p = 0.021), greater peak knee internal rotation moments (r = 0.41; p = 0.048), greater hip frontal plane excursion (r = 0.49; p = 0.017), and less knee transverse plane excursion (r = -0.56; p = 0.004) during unanticipated single-leg landing and cutting tasks. In addition, a statistical trend was detected between hip external rotator strength and peak hip frontal plane moments (r = 0.39; p = 0.06). The results suggest that females with greater hip external rotator strength demonstrate better dynamic control of the lower extremity during unanticipated single-leg landing and cutting tasks and provide further support for the link between hip strength and lower extremity landing mechanics. PMID:26110347

  16. Centrifugally activated bearing for high-speed rotating machinery

    DOEpatents

    Post, Richard F.

    1994-01-01

    A centrifugally activated bearing is disclosed. The bearing includes an annular member that extends laterally and radially from a central axis. A rotating member that rotates about the central axis relative to the annular member is also included. The rotating member has an interior chamber that surrounds the central axis and in which the annular member is suspended. Furthermore, the interior chamber has a concave shape for retaining a lubricant therein while the rotating member is at rest and for retaining a lubricant therein while the rotating member is rotating. The concave shape is such that while the rotating member is rotating a centrifugal force causes a lubricant to be forced away from the central axis to form a cylindrical surface having an axis collinear with the central axis. This centrifugally displaced lubricant provides restoring forces to counteract lateral displacement during operation.

  17. Centrifugally activated bearing for high-speed rotating machinery

    DOEpatents

    Post, R.F.

    1994-02-15

    A centrifugally activated bearing is disclosed. The bearing includes an annular member that extends laterally and radially from a central axis. A rotating member that rotates about the central axis relative to the annular member is also included. The rotating member has an interior chamber that surrounds the central axis and in which the annular member is suspended. Furthermore, the interior chamber has a concave shape for retaining a lubricant therein while the rotating member is at rest and for retaining a lubricant therein while the rotating member is rotating. The concave shape is such that while the rotating member is rotating a centrifugal force causes a lubricant to be forced away from the central axis to form a cylindrical surface having an axis collinear with the central axis. This centrifugally displaced lubricant provides restoring forces to counteract lateral displacement during operation. 4 figures.

  18. An eccentric- and concentric-strength profile of shoulder external and internal rotator muscles in professional baseball pitchers.

    PubMed

    Sirota, S C; Malanga, G A; Eischen, J J; Laskowski, E R

    1997-01-01

    The purpose of this study was to establish a data base on the isokinetic eccentric muscular performance characteristics of external and internal rotator muscles in the shoulders of professional baseball pitchers. Concentric data are also included and compared with previously published concentric studies. Twenty-five professional baseball pitchers were evaluated with a Kin-Com isokinetic dynamometer. The subjects tested had a mean age of 23.5 years and a mean body weight of 199 pounds. Eccentric and concentric isokinetic tests were performed at 60 and 120 deg/sec. The testing protocol was standardized for each subject. Test results indicated no statistically significant difference in mean torque between throwing and nonthrowing shoulders for either external or internal rotator muscle groups. Eccentric strength was significantly greater than concentric strength for all muscle groups tested. The external-to-internal rotator muscle strength ratios were well above those previously published for high school through professional pitchers. Mean torque-to-lean body weight ratios were also included to establish a data base. This study establishes one of the first data bases for eccentric isokinetic muscle strength of shoulder rotator muscles in professional baseball pitchers. The data may help clinicians prevent and rehabilitate shoulder injuries in professional throwing athletes.

  19. The QBO and weak external forcing by solar activity: A three dimensional model study

    NASA Technical Reports Server (NTRS)

    Dameris, M.; Ebel, A.

    1989-01-01

    A better understanding is attempted of the physical mechanisms leading to significant correlations between oscillations in the lower and middle stratosphere and solar variability associated with the sun's rotation. A global 3-d mechanistic model of the middle atmosphere is employed to investigate the effects of minor artificially induced perturbations. The aim is to explore the physical mechanisms of the dynamical response especially of the stratosphere to weak external forcing as it may result from UV flux changes due to solar rotation. First results of numerical experiments dealing about the external forcing of the middle atmosphere by solar activity were presented elsewhere. Different numerical studies regarding the excitation and propagation of weak perturbations have been continued since then. The model calculations presented are made to investigate the influence of the quasi-biennial oscillation (QBO) on the dynamical response of the middle atmosphere to weak perturbations by employing different initial wind fields which represent the west and east phase of the QBO.

  20. The Dosimetric Impact of Prostate Rotations During Electromagnetically Guided External-Beam Radiation Therapy

    SciTech Connect

    Amro, Hanan; Hamstra, Daniel A.; Mcshan, Daniel L.; Sandler, Howard; Vineberg, Karen; Hadley, Scott; Litzenberg, Dale

    2013-01-01

    Purpose: To study the impact of daily rotations and translations of the prostate on dosimetric coverage during radiation therapy (RT). Methods and Materials: Real-time tracking data for 26 patients were obtained during RT. Intensity modulated radiation therapy plans meeting RTOG 0126 dosimetric criteria were created with 0-, 2-, 3-, and 5-mm planning target volume (PTV) margins. Daily translations and rotations were used to reconstruct prostate delivered dose from the planned dose. D{sub 95} and V{sub 79} were computed from the delivered dose to evaluate target coverage and the adequacy of PTV margins. Prostate equivalent rotation is a new metric introduced in this study to quantify prostate rotations by accounting for prostate shape and length of rotational lever arm. Results: Large variations in prostate delivered dose were seen among patients. Adequate target coverage was met in 39%, 65%, and 84% of the patients for plans with 2-, 3-, and 5-mm PTV margins, respectively. Although no correlations between prostate delivered dose and daily rotations were seen, the data showed a clear correlation with prostate equivalent rotation. Conclusions: Prostate rotations during RT could cause significant underdosing even if daily translations were managed. These rotations should be managed with rotational tolerances based on prostate equivalent rotations.

  1. Magnetic island and plasma rotation under external resonant magnetic perturbation in the T-10 tokamak

    NASA Astrophysics Data System (ADS)

    Eliseev, L. G.; Ivanov, N. V.; Kakurin, A. M.; Melnikov, A. V.; Perfilov, S. V.

    2015-05-01

    Experimental comparison of the m = 2, n = 1 mode and plasma rotation velocities at q = 2 magnetic surface in a wide range of the mode amplitudes is presented. Phase velocity of the mode rotation is measured with a set of poloidal magnetic field sensors located at the inner side of the vacuum vessel wall. Plasma rotation velocity at the q = 2 magnetic surface in the direction of the mode phase velocity is measured with the heavy ion beam probe diagnostics. In the presence of a static Resonant Magnetic Perturbation (RMP), the rotation is irregular that appears as cyclical variations of the mode and plasma instantaneous velocities. The period of these variations is equal to the period of the mode oscillations. In the case of high mode amplitude, the rotation irregularity of the mode is consistent with the rotation irregularity of the resonant plasma layer. On the contrary, the observed rise of the mode rotation irregularity in the case of low mode amplitude occurs without an increase of the rotation irregularity of the resonant plasma layer. The experimental results are simulated and analyzed with the TEAR code based on the two-fluid MHD approximation. Calculated irregularities of the mode and plasma rotation depend on the mode amplitude similar to the experimental data. For large islands, the rotation irregularity is attributed to oscillations of the electromagnetic torque applied to the resonant plasma layer. For small islands, the deviation of the mode rotation velocity from the plasma velocity occurs due to the effect of finite plasma resistivity.

  2. Error field assessment from driven rotation of stable external kinks at EXTRAP-T2R reversed field pinch

    NASA Astrophysics Data System (ADS)

    Volpe, F. A.; Frassinetti, L.; Brunsell, P. R.; Drake, J. R.; Olofsson, K. E. J.

    2013-04-01

    A new non-disruptive error field (EF) assessment technique not restricted to low density and thus low beta was demonstrated at the EXTRAP-T2R reversed field pinch. Stable and marginally stable external kink modes of toroidal mode number n = 10 and n = 8, respectively, were generated, and their rotation sustained, by means of rotating magnetic perturbations of the same n. Due to finite EFs, and in spite of the applied perturbations rotating uniformly and having constant amplitude, the kink modes were observed to rotate non-uniformly and be modulated in amplitude. This behaviour was used to precisely infer the amplitude and approximately estimate the toroidal phase of the EF. A subsequent scan permitted to optimize the toroidal phase. The technique was tested against deliberately applied as well as intrinsic EFs of n = 8 and 10. Corrections equal and opposite to the estimated error fields were applied. The efficacy of the error compensation was indicated by the increased discharge duration and more uniform mode rotation in response to a uniformly rotating perturbation. The results are in good agreement with theory, and the extension to lower n, to tearing modes and to tokamaks, including ITER, is discussed.

  3. Coarsening dynamics of binary liquids with active rotation.

    PubMed

    Sabrina, Syeda; Spellings, Matthew; Glotzer, Sharon C; Bishop, Kyle J M

    2015-11-21

    Active matter comprised of many self-driven units can exhibit emergent collective behaviors such as pattern formation and phase separation in both biological (e.g., mussel beds) and synthetic (e.g., colloidal swimmers) systems. While these behaviors are increasingly well understood for ensembles of linearly self-propelled "particles", less is known about the collective behaviors of active rotating particles where energy input at the particle level gives rise to rotational particle motion. A recent simulation study revealed that active rotation can induce phase separation in mixtures of counter-rotating particles in 2D. In contrast to that of linearly self-propelled particles, the phase separation of counter-rotating fluids is accompanied by steady convective flows that originate at the fluid-fluid interface. Here, we investigate the influence of these flows on the coarsening dynamics of actively rotating binary liquids using a phenomenological, hydrodynamic model that combines a Cahn-Hilliard equation for the fluid composition with a Navier-Stokes equation for the fluid velocity. The effect of active rotation is introduced though an additional force within the Navier-Stokes equations that arises due to gradients in the concentrations of clockwise and counter-clockwise rotating particles. Depending on the strength of active rotation and that of frictional interactions with the stationary surroundings, we observe and explain new dynamical behaviors such as "active coarsening" via self-generated flows as well as the emergence of self-propelled "vortex doublets". We confirm that many of the qualitative behaviors identified by the continuum model can also be found in discrete, particle-based simulations of actively rotating liquids. Our results highlight further opportunities for achieving complex dissipative structures in active materials subject to distributed actuation. PMID:26345231

  4. Method to rotate an endovascular device around the axis of a vessel using an external magnetic field.

    PubMed

    Florin, E; Rangwala, H S; Rudin, S

    2007-01-01

    A magnetic guidance methodology to rotate a device around the catheter axis is proposed. The specific medical application is to intracranial aneurysms. An endovascular device, the asymmetric stent, has a low porosity region that is rotated to cover the aneurysm neck so as to reduce the blood flow into and hence obliterate the aneurysm. The magnetic guidance system consists of a magnetic device attached to the asymmetric stent and an external homogeneous magnetic field of 0.1 T. This magnetic field puts a torque on the magnetic moment of the magnetic device, thereby rotating the stent for proper orientation. For the magnetic device with the required magnetic moment of 0.001 A m2, a cylindrical neodymium permanent magnet is proposed due to its favorable material characteristics while a coil electromagnet with iron core appears impractical due to demagnetizing effects.

  5. Magnetic island and plasma rotation under external resonant magnetic perturbation in the T-10 tokamak

    SciTech Connect

    Eliseev, L. G.; Ivanov, N. V. Kakurin, A. M.; Perfilov, S. V.; Melnikov, A. V.

    2015-05-15

    Experimental comparison of the m = 2, n = 1 mode and plasma rotation velocities at q = 2 magnetic surface in a wide range of the mode amplitudes is presented. Phase velocity of the mode rotation is measured with a set of poloidal magnetic field sensors located at the inner side of the vacuum vessel wall. Plasma rotation velocity at the q = 2 magnetic surface in the direction of the mode phase velocity is measured with the heavy ion beam probe diagnostics. In the presence of a static Resonant Magnetic Perturbation (RMP), the rotation is irregular that appears as cyclical variations of the mode and plasma instantaneous velocities. The period of these variations is equal to the period of the mode oscillations. In the case of high mode amplitude, the rotation irregularity of the mode is consistent with the rotation irregularity of the resonant plasma layer. On the contrary, the observed rise of the mode rotation irregularity in the case of low mode amplitude occurs without an increase of the rotation irregularity of the resonant plasma layer. The experimental results are simulated and analyzed with the TEAR code based on the two-fluid MHD approximation. Calculated irregularities of the mode and plasma rotation depend on the mode amplitude similar to the experimental data. For large islands, the rotation irregularity is attributed to oscillations of the electromagnetic torque applied to the resonant plasma layer. For small islands, the deviation of the mode rotation velocity from the plasma velocity occurs due to the effect of finite plasma resistivity.

  6. A Profile of Glenohumeral Internal and External Rotation Motion in the Uninjured High School Baseball Pitcher, Part II: Strength

    PubMed Central

    Hurd, Wendy J.; Kaplan, Kevin M.; ElAttrache, Neal S.; Jobe, Frank W.; Morrey, Bernard F.; Kaufman, Kenton R.

    2011-01-01

    Context: A database describing the range of normal rotator cuff strength values in uninjured high school pitchers has not been established. Chronologic factors that contribute to adaptations in strength also have not been established. Objectives: To establish a normative profile of rotator cuff strength in uninjured high school baseball pitchers and to determine whether bilateral differences in rotator cuff strength are normal findings in this age group. Design: Cohort study. Setting: Baseball playing field. Patients or Other Participants: A total of 165 uninjured male high school baseball pitchers (age = 16 ± 1 years, height = 1.8 ± 0.1 m, mass = 76.8 ± 10.1 kg, pitching experience = 7 ± 2 years). Main Outcome Measure(s): Isometric rotator cuff strength was measured bilaterally with a handheld dynamometer. We calculated side-to-side differences in strength (external rotation [ER], internal rotation [IR], and the ratio of ER:IR at 90° of abduction), differences in strength by age, and the influence of chronologic factors (participant age, years of pitching experience) on limb strength. Results: Side-to-side differences in strength were found for ER, IR, and ER:IR ratio at 90° of abduction. Age at the time of testing was a significant but weak predictor of both ER strength (R2 = 0.032, P = .02) and the ER:IR ratio (R2 = 0.051, P = .004) at 90° of abduction. Conclusions: We established a normative profile of rotator cuff strength for the uninjured high school baseball pitcher that might be used to assist clinicians and researchers in the interpretation of muscle strength performance in this population. These data further suggested that dominant-limb adaptations in rotator cuff strength are a normal finding in this age group and did not demonstrate that these adaptations were a consequence of the age at the time of testing or the number of years of pitching experience. PMID:21669099

  7. Effect of Resistance Training Maintaining the Joint Angle-torque Profile Using a Haptic-based Machine on Shoulder Internal and External Rotation.

    PubMed

    Kim, Yeonghun; Lee, Kunwoo; Moon, Jeheon; Koo, Dohoon; Park, Jaewoo; Kim, Kyengnam; Hong, Daehie; Shin, Inshik

    2014-04-01

    [Purpose] The aim of this study was to present an individualized resistance training method to enable exercise while maintaining an exercise load that is set according to an individual's joint angle-torque using a haptic-based resistance training machine. [Methods] Five participants (machine group) performed individualized shoulder internal and external rotation training with a haptic resistance training machine, while another five participants performed general dumbbell-based shoulder internal and external rotation training for eight weeks. Internal and external rotation powers of subjects were measured using an isokinetic machine before and after training. [Results] The average powers of both shoulder internal and external rotation has been improved after training (25.72%, 13.62%). The improvement in power of external rotation in the machine group was significantly higher than that in the control group. [Conclusion] This study proposes a haptic-based individualized rotator cuff muscle training method. The training protocol maintaining the joint angle-torque profile showed better improvement of shoulder internal/external rotation than dumbbell training.

  8. Effect of Resistance Training Maintaining the Joint Angle-torque Profile Using a Haptic-based Machine on Shoulder Internal and External Rotation

    PubMed Central

    Kim, Yeonghun; Lee, Kunwoo; Moon, Jeheon; Koo, Dohoon; Park, Jaewoo; Kim, Kyengnam; Hong, Daehie; Shin, Inshik

    2014-01-01

    [Purpose] The aim of this study was to present an individualized resistance training method to enable exercise while maintaining an exercise load that is set according to an individual’s joint angle-torque using a haptic-based resistance training machine. [Methods] Five participants (machine group) performed individualized shoulder internal and external rotation training with a haptic resistance training machine, while another five participants performed general dumbbell-based shoulder internal and external rotation training for eight weeks. Internal and external rotation powers of subjects were measured using an isokinetic machine before and after training. [Results] The average powers of both shoulder internal and external rotation has been improved after training (25.72%, 13.62%). The improvement in power of external rotation in the machine group was significantly higher than that in the control group. [Conclusion] This study proposes a haptic-based individualized rotator cuff muscle training method. The training protocol maintaining the joint angle-torque profile showed better improvement of shoulder internal/external rotation than dumbbell training. PMID:24764626

  9. Incentive-elicited mesolimbic activation and externalizing symptomatology in adolescents

    PubMed Central

    Bjork, James M.; Chen, Gang; Smith, Ashley R.; Hommer, Daniel W.

    2010-01-01

    Background Opponent-process theories of externalizing disorders (ExD) attribute them to some combination of overactive reward processing systems and/or underactive impaired behavior inhibition systems. Reward processing has been indexed by recruitment of incentive-motivational neurocircuitry of the ventral striatum (VS), including nucleus accumbens (NAcc). Methods We used functional magnetic resonance imaging (fMRI) with an incentive task to determine whether externalizing symptomatology in adolescence is correlated with an enhanced VS recruitment by cues for rewards, or by deliveries of rewards. Twelve community-recruited adolescents with externalizing disorders (AED) and 12 age/gender-matched controls responded to targets to win or avoid losing $0, $0.20, $1, $5, or an unknown amount (ranging from $0.20–$5). Results Cues to respond for rewards activated the NAcc (relative to cues for no incentive), in both subject groups similarly, with greatest NAcc recruitment by cues for the largest reward. Loss-anticipatory NAcc signal increase was detected in a volume-of-interest analysis- but this increase occurred only in trials when subjects hit the target. Relative to controls, AED showed significantly elevated NAcc activation by a linear contrast between reward notification versus notification of failure to win reward. In a post hoc reanalysis, VS and pregenual anterior cingulate activation by the reward versus nonreward outcome contrast also directly correlated with Child Behavior Checklist (CBCL) Externalizing total scores (across all subjects) in lieu of a binary diagnosis. Finally, both groups showed right insula activation by loss notifications (contrasted with avoided losses). Conclusions Externalizing behavior, whether assessed dimensionally with a questionnaire, or in the form of a diagnostic categorization, is associated with an exaggerated limbic response to outcomes of reward-directed behavior. This could be a neurobiological signature of the behavioral

  10. Active Wavelength Control of an External Cavity Quantum Cascade Laser

    PubMed Central

    Tsai, Tracy; Wysocki, Gerard

    2012-01-01

    We present an active wavelength control system for grating-based external cavity lasers that increases the accuracy of predicting the lasing wavelength based on the grating equation and significantly improves scan-to-scan wavelength/frequency repeatability. The ultimate 3σ precision of a frequency scan is determined by the scan-to-scan repeatability of 0.042 cm−1. Since this control method can be applied to any external cavity laser with little to no modification, such a precision provides an excellent opportunity for spectroscopic applications that target molecular absorption lines at standard atmospheric conditions. PMID:23483850

  11. Gender Difference Does Not Mean Genetic Difference: Externalizing Improves Performance in Mental Rotation

    ERIC Educational Resources Information Center

    Moe, Angelica

    2012-01-01

    The fear of underperforming owing to stereotype threat affects women's performance in tasks such as mathematics, chess, and spatial reasoning. The present research considered mental rotation and explored effects on performance and on regulatory focus of instructions pointing to different explanations for gender differences. Two hundred and one…

  12. A Profile of Glenohumeral Internal and External Rotation Motion in the Uninjured High School Baseball Pitcher, Part I: Motion

    PubMed Central

    Hurd, Wendy J.; Kaplan, Kevin M.; ElAttrache, Neal S.; Jobe, Frank W.; Morrey, Bernard F.; Kaufman, Kenton R.

    2011-01-01

    Context: The magnitude of motion that is normal for the throwing shoulder in uninjured baseball pitchers has not been established. Chronologic factors contributing to adaptations in motion present in the thrower's shoulder also have not been established. Objectives: To develop a normative profile of glenohumeral rotation motion in uninjured high school baseball pitchers and to evaluate the effect of chronologic characteristics on the development of adaptations in shoulder rotation motion. Design: Cohort study. Setting: Baseball playing field. Patients or Other Participants: A total of 210 uninjured male high school baseball pitchers (age = 16±1.1 years, height = 1.8 + 0.1 m, mass = 77.5±11.2 kg, pitching experience = 6±2.3 years). Intervention(s): Using standard goniometric techniques, we measured passive rotational glenohumeral range of motion bilaterally with participants in the supine position. Main Outcome Measure(s): Paired t tests were performed to identify differences in motion between limbs for the group. Analysis of variance and post hoc Tukey tests were conducted to identify differences in motion by age. Linear regressions were performed to determine the influence of chronologic factors on limb motion. Results: Rotation motion characteristics for the population were established. We found no difference between sides for external rotation (ER) at 0° of abduction (t209 = 0.658, P = .51), but we found side-to-side differences in ER (t209 = −13.012, P<.001) and internal rotation (t209 = 15.304, P<.001) at 90° of abduction. Age at the time of testing was a significant negative predictor of ER motion for the dominant shoulder (R2 = 0.019, P = .049) because less ER motion occurred at the dominant shoulder with advancing age. We found no differences in rotation motion in the dominant shoulder across ages (F4,205 range, 0.451–1.730, P>.05). Conclusions: This range-of-motion profile might be used to assist with the interpretation of normal and atypical

  13. Dynamical theory of active cellular response to external stress

    NASA Astrophysics Data System (ADS)

    de, Rumi; Safran, Samuel A.

    2008-09-01

    We present a comprehensive, theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes both the forces that arise from the deformation of the matrix as well as forces due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate the time-dependent response of both the magnitude and the direction of the elastic dipole that characterizes the active forces exerted by the cell, for various situations. For static or quasistatic external stress, cells orient parallel to the stress while for high frequency dynamic external stress, cells orient nearly perpendicular. Both numerical and analytical calculations of these effects are presented. In addition we predict the relaxation time for the cellular response for both slowly and rapidly varying external stresses; several characteristic scaling regimes for the relaxation time as a function of applied frequency are predicted. We also treat the case of cells for which the regulation of the stress fibers and focal adhesions is controlled by strain (instead of stress) and show that the predicted dependence of the cellular orientation on the Poisson ratio of the matrix can differentiate strain vs stress regulation of cellular response.

  14. Dynamical theory of active cellular response to external stress.

    PubMed

    De, Rumi; Safran, Samuel A

    2008-09-01

    We present a comprehensive, theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes both the forces that arise from the deformation of the matrix as well as forces due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate the time-dependent response of both the magnitude and the direction of the elastic dipole that characterizes the active forces exerted by the cell, for various situations. For static or quasistatic external stress, cells orient parallel to the stress while for high frequency dynamic external stress, cells orient nearly perpendicular. Both numerical and analytical calculations of these effects are presented. In addition we predict the relaxation time for the cellular response for both slowly and rapidly varying external stresses; several characteristic scaling regimes for the relaxation time as a function of applied frequency are predicted. We also treat the case of cells for which the regulation of the stress fibers and focal adhesions is controlled by strain (instead of stress) and show that the predicted dependence of the cellular orientation on the Poisson ratio of the matrix can differentiate strain vs stress regulation of cellular response.

  15. Ultrasonography as a diagnostic tool in assessing deltoid ligament injury in supination external rotation fractures of the ankle.

    PubMed

    Henari, Shwan; Banks, Louisa N; Radovanovic, Ingrid; Radiovanovic, Ingrid; Queally, Joseph; Morris, Seamus

    2011-10-01

    The medial deltoid ligament is the primary stabilizing structure in the ankle joint following lateral malleolar fracture. However, medial deltoid ligament ruptures are difficult to diagnose using current imaging modalities. We hypothesized that ultrasonography can be used to accurately allow early clinical assessment of ankle fracture stability, thereby negating the need to perform plain film stress views of the acutely injured ankle. This prospective study included 12 patients (age range, 18-72) with supination external rotation fractures requiring operative fixation. Following induction of anesthesia, ultrasonography examination was performed, followed by an arthrogram under fluoroscopic screening. Radiographs, ultrasonography, and arthrographic findings were compared. There was 100% correlation between ultrasonography and arthrogram findings. Ultrasonography accurately diagnosed medial deltoid rupture with a sensitivity of 100% and specificity of 100%. Plain film radiographs of the ankle had a sensitivity of 57.1% and a specificity of 60%. The difference between these was significant (χ(2)=.0091). This study demonstrates diagnostic ultrasonography to be an accurate diagnostic modality in assessing medial deltoid ligament integrity in patients with supination external rotation fractures. It offers the same sensitivity and specificity as arthrography without the need for additional invasive procedures. Its relative ease of use and lack of ionizing radiation make it a potentially useful tool, particularly in a busy trauma service.

  16. Every Elementary Particle When Created, Will Exhibit No Motion, Linear, Rotational and/or Vibrational Motion Which May Later Be Modified By External Forces: A Natural Law

    NASA Astrophysics Data System (ADS)

    Brekke, Stewart

    2011-04-01

    All masses are vibrating, rotating and/or moving linearly. Curivlinear motion is linear motion under external forces. The excess energy of creation of a particle may also go into creating vibratory, rotational and/or linear motion or no motion at all. External forces such as particle collisions or force fields may alter the original linear, vibratory and/or rotational motion of the particle. Since all elementary particles always obey this behavior, the statement is a natural law. The equation for this law for any particle is E = mc2 + 1 / 2 mv2 + 1 / 2 Iω2 + 1 / 2 kx02 .

  17. Rehabilitation of the Overhead Throwing Athlete: There Is More to It Than Just External Rotation/Internal Rotation Strengthening.

    PubMed

    Wilk, Kevin E; Arrigo, Christopher A; Hooks, Todd R; Andrews, James R

    2016-03-01

    The repetitive nature of throwing manifests characteristic adaptive changes to the shoulder, scapulothoracic, and hip/pelvis complexes that result in a set of unique physical traits in the overhead throwing athlete. An effective rehabilitation program is dependent upon an accurate evaluation and differential diagnosis to determine the causative factors for the athlete's pathologic features. The treatment program should be individualized with specific strengthening and flexibility exercises to achieve the dynamic stability that is required for overhead function. In this article we describe the characteristics of the throwing shoulder, along with a multiphased rehabilitation program that allows for the restoration of strength, mobility, endurance, and power and is aimed toward a return to unrestricted sporting activity. We also describe exercises that link the upper and lower extremities because of the importance of core control and leg strength in the development of power during the act of throwing. Additionally, proper throwing mechanics, utilization of pitch counts, appropriate rest, and proper off-season conditioning will help decrease overall injury risk in the overhead throwing athlete.

  18. Rehabilitation of the Overhead Throwing Athlete: There Is More to It Than Just External Rotation/Internal Rotation Strengthening.

    PubMed

    Wilk, Kevin E; Arrigo, Christopher A; Hooks, Todd R; Andrews, James R

    2016-03-01

    The repetitive nature of throwing manifests characteristic adaptive changes to the shoulder, scapulothoracic, and hip/pelvis complexes that result in a set of unique physical traits in the overhead throwing athlete. An effective rehabilitation program is dependent upon an accurate evaluation and differential diagnosis to determine the causative factors for the athlete's pathologic features. The treatment program should be individualized with specific strengthening and flexibility exercises to achieve the dynamic stability that is required for overhead function. In this article we describe the characteristics of the throwing shoulder, along with a multiphased rehabilitation program that allows for the restoration of strength, mobility, endurance, and power and is aimed toward a return to unrestricted sporting activity. We also describe exercises that link the upper and lower extremities because of the importance of core control and leg strength in the development of power during the act of throwing. Additionally, proper throwing mechanics, utilization of pitch counts, appropriate rest, and proper off-season conditioning will help decrease overall injury risk in the overhead throwing athlete. PMID:26972270

  19. Activity and Rotation in the Young Cluster h Per

    NASA Astrophysics Data System (ADS)

    Argiroffi, C.; Caramazza, M.; Micela, G.; Moraux, E.; Bouvier, J.

    2014-08-01

    We study the rotation-activity relationship for low-mass members of the young cluster h Persei, a ~13 Myr old cluster. h Per, thanks to its age, allows us to link the rotation-activity relation observed for main-sequence stars to the still unexplained activity levels of very young clusters. We constrained the activity levels of h Per members by analyzing a deep Chandra/ACIS-I observation pointed to the central field of h Per. We combined this X-ray catalog with the catalog of h Per members with measured rotational period, presented by Moraux et al. (2013). We obtained a final catalog of 202 h Per members with measured X-ray luminosity and rotational period. We investigate the rotation-activity relation of h Per members considering different mass ranges. We find that stars with 1.3 M⊙ > M 1.4 M⊙ show significant evidence of supersaturation for short periods. This phenomenon is instead not observed for lower mass stars.

  20. Polarization rotator-splitters in standard active silicon photonics platforms.

    PubMed

    Sacher, Wesley D; Barwicz, Tymon; Taylor, Benjamin J F; Poon, Joyce K S

    2014-02-24

    We demonstrate various silicon-on-insulator polarization management structures based on a polarization rotator-splitter that uses a bi-level taper TM0-TE1 mode converter. The designs are fully compatible with standard active silicon photonics platforms with no new levels required and were implemented in the IME baseline and IME-OpSIS silicon photonics processes. We demonstrate a polarization rotator-splitter with polarization crosstalk < -13 dB over a bandwidth of 50 nm. Then, we improve the crosstalk to < -22 dB over a bandwidth of 80 nm by integrating the polarization rotator-splitter with directional coupler polarization filters. Finally, we demonstrate a polarization controller by integrating the polarization rotator-splitters with directional couplers, thermal tuners, and PIN diode phase shifters. PMID:24663698

  1. Generalized investigation of the rotation-activity relation: favoring rotation period instead of Rossby number

    SciTech Connect

    Reiners, A.; Passegger, V. M.; Schüssler, M.

    2014-10-20

    Magnetic activity in Sun-like and low-mass stars causes X-ray coronal emission which is stronger for more rapidly rotating stars. This relation is often interpreted in terms of the Rossby number, i.e., the ratio of rotation period to convective overturn time. We reconsider this interpretation on the basis of the observed X-ray emission and rotation periods of 821 stars with masses below 1.4 M {sub ☉}. A generalized analysis of the relation between X-ray luminosity normalized by bolometric luminosity, L {sub X}/L {sub bol}, and combinations of rotational period, P, and stellar radius, R, shows that the Rossby formulation does not provide the solution with minimal scatter. Instead, we find that the relation L {sub X}/L {sub bol}∝P {sup –2} R {sup –4} optimally describes the non-saturated fraction of the stars. This relation is equivalent to L {sub X}∝P {sup –2}, indicating that the rotation period alone determines the total X-ray emission. Since L {sub X} is directly related to the magnetic flux at the stellar surface, this means that the surface flux is determined solely by the star's rotation and is independent of other stellar parameters. While a formulation in terms of a Rossby number would be consistent with these results if the convective overturn time scales exactly as L{sub bol}{sup −1/2}, our generalized approach emphasizes the need to test a broader range of mechanisms for dynamo action in cool stars.

  2. Influence of external magnetic fields on the freezing temperature Tf of Ni 79Mn 21 alloys: Evidence for anisotropy rotation

    NASA Astrophysics Data System (ADS)

    Öner, Y.; Firat, T.; Ercan, İ.; Aktaş, B.

    1988-04-01

    DC magnetization measurements have been performed for Ni 79Mn 21 alloys in the temperature range of 4.2 to 50 K. Taking the demagnetizing field into account, the influence of an external magnetic field, Hext, on the re-entrant spin-glass transition temperature Tf of this alloy has been investigated. It has been observed that Tf is independent of Hext if Hext is sma ller than the demagnetizing field HD ( = NMs) where N is the demagnetizing factor; Ms is the value of the saturation magnetization. However, for higher fields, Tf is displaced towards lower temperatures. These results are interpreted in terms of anisotropy rotation based on the "domain-anisotropy" model.

  3. Incidence of Peroneal Tendinopathy After Application of a Posterior Antiglide Plate for Repair of Supination External Rotation Lateral Malleolar Fractures.

    PubMed

    Ahn, Jungtae; Kim, Sehun; Lee, Jung-Soo; Woo, Kyungjei; Sung, Ki-Sun

    2016-01-01

    Posterior antiglide plating is widely used to treat lateral malleolar fractures caused by supination-external rotation injuries. Despite its widespread use, this technique can be associated with postoperative peroneal tendinopathy. The purpose of the present observational review was to report the incidence of peroneal tendinopathy after the use of posterior antiglide plating to treat lateral malleolar fractures caused by a supination-external rotation injury. A total of 70 patients were followed up for a minimum of 12 (mean 55, range 12 to 109) months. Bony union was obtained in all cases after a mean of 57 (range 37 to 81) days. The median number of screw holes in the plate was 4.9 (range 4 to 7), and the median number of screws used to fixate the fibula was 6.58 (range 5 to 10). The mean American Orthopaedic Foot and Ankle Society hindfoot-ankle score at the final follow-up examination was 90.8 (range 55 to 100). Clinically, 3 (4.29%) of the 70 patients had lateral or posterolateral ankle pain indicative of peroneal tendinopathy after the index surgery, without any objective evidence. Of the 70 patients, 41 (58.57%) underwent surgical removal of the fibular hardware, 2 (4.87%) because of lateral ankle discomfort. At removal, inspection of the peroneal tendon sheath and/or tendons showed no gross evidence of tendinopathy in any of the patients. We concluded that the incidence of clinically evident peroneal tendon symptoms associated with posterior antiglide plating is low (4.3%), and direct operative inspection revealed no gross evidence of tendinopathy.

  4. Motion transition of active filaments: rotation without hydrodynamic interactions.

    PubMed

    Jiang, Huijun; Hou, Zhonghuai

    2014-02-21

    We investigate the dynamics of an active semiflexible filament in a bead–rod model involving dynamically the hydrodynamic interaction (HI), active force, filament flexibility and viscous drag. We find that the filament can show three distinct types of motion, namely, translation, snaking and rotation, with the variation of the rigidity or active force. The transition from translation to snaking is continuous and mainly due to transverse instability, while the snaking–rotation transition is first-order like and shown to result from a type of symmetry breaking associated with the shape kinematics. Of particular interest, we find that HI is not necessary for the rotation or snaking motion, but can enlarge remarkably the parameter regions in which they can occur. Combining with local collisions, we show that, for the parameter region where HI is essential for the maintenance of rotation curvature of a single filament, HI is also essential for the emergence of collective vortexes. Thus, our findings provide new insights into the subtle role of HI in the formation of collective structures in active systems PMID:24983114

  5. Ultrasensitive detection of nitric oxide at 5.33 μm by using external cavity quantum cascade laser-based Faraday rotation spectroscopy

    PubMed Central

    Lewicki, Rafał; Doty, James H.; Curl, Robert F.; Tittel, Frank K.; Wysocki, Gerard

    2009-01-01

    A transportable prototype Faraday rotation spectroscopic system based on a tunable external cavity quantum cascade laser has been developed for ultrasensitive detection of nitric oxide (NO). A broadly tunable laser source allows targeting the optimum Q3/2(3/2) molecular transition at 1875.81 cm−1 of the NO fundamental band. For an active optical path of 44 cm and 1-s lock-in time constant minimum NO detection limits (1σ) of 4.3 parts per billion by volume (ppbv) and 0.38 ppbv are obtained by using a thermoelectrically cooled mercury–cadmium–telluride photodetector and liquid nitrogen-cooled indium–antimonide photodetector, respectively. Laboratory performance evaluation and results of continuous, unattended monitoring of atmospheric NO concentration levels are reported. PMID:19625625

  6. Response of a partial wall to an external perturbation of rotating plasma

    SciTech Connect

    Atanasiu, C. V.; Zakharov, L. E.

    2013-09-15

    In this paper, we present the response of a 3D thin multiply connected wall to an external kink mode perturbation in axisymmetric tokamak configurations. To calculate the contribution of the plasma perturbed magnetic field in the vacuum region, we have made use of the concept of surface currents [following C. V. Atanasiu, A. H. Boozer, L. E. Zakharov, and A. A. Subbotin, Phys. Plasmas 6, 2781 (1999)]. The wall response is expressed in terms of a stream function of the wall surface currents, which are obtained by solving a diffusion type equation, taking into account the contribution of the wall currents themselves iteratively. The use of stream function makes the approach applicable for both well-studied earlier Resistive Wall Modes and for Wall Touching Kink Modes, which were discovered recently as a key phenomenon in disruptions [L. E. Zakharov, S. A. Galkin, and S. N. Gerasimov, Phys. Plasmas 19, 055703 (2012)]. New analytical expressions, suitable for numerical calculations of toroidal harmonics of the vacuum magnetic fields from the surface currents on axisymmetric shells, are derived.

  7. Rotation, activity, and lithium abundance in cool binary stars

    NASA Astrophysics Data System (ADS)

    Strassmeier, K. G.; Weber, M.; Granzer, T.; Järvinen, S.

    2012-10-01

    We have used two robotic telescopes to obtain time-series high-resolution optical echelle spectroscopy and V I and/or by photometry for a sample of 60 active stars, mostly binaries. Orbital solutions are presented for 26 double-lined systems and for 19 single-lined systems, seven of them for the first time but all of them with unprecedented phase coverage and accuracy. Eighteen systems turned out to be single stars. The total of 6609 {R=55 000} échelle spectra are also used to systematically determine effective temperatures, gravities, metallicities, rotational velocities, lithium abundances and absolute Hα-core fluxes as a function of time. The photometry is used to infer unspotted brightness, {V-I} and/or b-y colors, spot-induced brightness amplitudes and precise rotation periods. An extra 22 radial-velocity standard stars were monitored throughout the science observations and yield a new barycentric zero point for our STELLA/SES robotic system. Our data are complemented by literature data and are used to determine rotation-temperature-activity relations for active binary components. We also relate lithium abundance to rotation and surface temperature. We find that 74 % of all known rapidly-rotating active binary stars are synchronized and in circular orbits but 26 % (61 systems) are rotating asynchronously of which half have {P_rot>P_orb} and {e>0}. Because rotational synchronization is predicted to occur before orbital circularization active binaries should undergo an extra spin-down besides tidal dissipation. We suspect this to be due to a magnetically channeled wind with its subsequent braking torque. We find a steep increase of rotation period with decreasing effective temperature for active stars, P_rot ∝ T_eff-7, for both single and binaries, main sequence and evolved. For inactive, single giants with {P_rot>100} d, the relation is much weaker, {P_rot ∝ T_eff-1.12}. Our data also indicate a period-activity relation for Hα of the form {R_Hα ∝ P

  8. Tracking Active Region NOAA 12192 in Multiple Carrington Rotations

    NASA Astrophysics Data System (ADS)

    Jain, Kiran; Tripathy, Sushant C.; Hill, Frank

    2015-04-01

    Active region NOAA 12192 appeared on the visible solar disk on October 18, 2014 and grew rapidly into the largest such region since 1990. During its entire transit across the Earth facing side of the Sun, it produced a significant number of X- and M-class flares. The combination of front-side and helioseismic far-side images clearly indicated that it lived through several Carrington rotations. In this paper, using Dopplergrams from GONG and HMI, we present a study on mode parameters, viz. oscillation frequencies, amplitude, and sub-surface flows and investigate how these vary with the evolution of active region in multiple rotations. We also present a detailed comparison between NOAA 10486 (the biggest active region in cycle 23) and NOAA 12192, and discuss the similarities/differences between them.

  9. Deriving Stellar Inclination of Slow Rotators Using Stellar Activity

    NASA Astrophysics Data System (ADS)

    Dumusque, X.

    2014-12-01

    Stellar inclination is an important parameter for many astrophysical studies. Although different techniques allow us to estimate stellar inclination for fast rotators, it becomes much more difficult when stars are rotating slower than ~2-2.5 km s-1. By using the new activity simulation SOAP 2.0 which can reproduce the photometric and spectroscopic variations induced by stellar activity, we are able to fit observations of solar-type stars and derive their inclination. For HD 189733, we estimate the stellar inclination to be i=84+6-20 deg, which implies a star-planet obliquity of \\psi =4+18-4 considering previous measurements of the spin-orbit angle. For α Cen B, we derive an inclination of i=45+9-19, which implies that the rotational spin of the star is not aligned with the orbital spin of the α Cen binary system. In addition, assuming that α Cen Bb is aligned with its host star, no transit would occur. The inclination of α Cen B can be measured using 40 radial-velocity measurements, which is remarkable given that the projected rotational velocity of the star is smaller than 1.15 km s-1. Based on observations made with the MOST satellite, the HARPS instrument on the ESO 3.6 m telescope at La Silla Observatory (Chile), and the SOPHIE instrument at the Observatoire de Haute Provence (France).

  10. Deriving stellar inclination of slow rotators using stellar activity

    SciTech Connect

    Dumusque, X.

    2014-12-01

    Stellar inclination is an important parameter for many astrophysical studies. Although different techniques allow us to estimate stellar inclination for fast rotators, it becomes much more difficult when stars are rotating slower than ∼2-2.5 km s{sup –1}. By using the new activity simulation SOAP 2.0 which can reproduce the photometric and spectroscopic variations induced by stellar activity, we are able to fit observations of solar-type stars and derive their inclination. For HD 189733, we estimate the stellar inclination to be i=84{sub −20}{sup +6} deg, which implies a star-planet obliquity of ψ=4{sub −4}{sup +18} considering previous measurements of the spin-orbit angle. For α Cen B, we derive an inclination of i=45{sub −19}{sup +9}, which implies that the rotational spin of the star is not aligned with the orbital spin of the α Cen binary system. In addition, assuming that α Cen Bb is aligned with its host star, no transit would occur. The inclination of α Cen B can be measured using 40 radial-velocity measurements, which is remarkable given that the projected rotational velocity of the star is smaller than 1.15 km s{sup –1}.

  11. THE IMPACT OF SAGITTAL PLANE HIP POSITION ON ISOMETRIC FORCE OF HIP EXTERNAL ROTATOR AND INTERNAL ROTATOR MUSCLES IN HEALTHY YOUNG ADULTS

    PubMed Central

    Wong, Anson L. K.; Rickards, Cory

    2014-01-01

    Purpose/Background: Hip external rotator (ER) and internal rotator (IR) muscle weakness is theorized to be associated with lower extremity injury in athletes including knee ligament tears and patellofemoral pain. Previous studies investigating hip musculature strength have utilized various sagittal plane hip positions for testing. The relationship between results at these different positions is unknown. Methods: Eighty healthy, pain‐free young adults participated in the study: 40 female, mean age 22.90 (± 2.32) years, and 40 male, mean age 23.50 (± 2.15) years. Peak isometric torque of bilateral hip ER and IR were tested at 90° and 0° of hip flexion with an instrumented dynamometer. Peak muscle forces were calculated. Peak forces were normalized by body mass. Mean normalized force was calculated for dominant and non‐dominant limbs for ER and IR in both positions. Male and female data were analyzed separately with paired t‐tests (2‐tailed). Reference values for average muscle force and torque were calculated for dominant and non‐dominant limbs for both hip positions. Results: Hip IR normalized peak force was greater at 90° compared to 0° flexion position bilaterally in both genders (p < .01). Hip ER normalized peak force was greater at 90° compared to 0° flexion in dominant limbs of both genders and in non‐dominant limbs of males (p < .01). Non‐dominant hip ER normalized force in females was greater at 90° versus 0° flexion; however, it was not significant (p = .092). Post hoc analysis of normalized average force (average over 5‐second contraction) yielded similar results. Conclusion: Clinicians and researchers should use consistent positioning for testing of hip ER and IR strength. This will improve certainty of determining if a patient’s strength has changed or if differences between groups are present. Reference values reported will be useful in order to determine if weakness is present and to set goals, particularly in cases of

  12. RELATIONSHIPS BETWEEN CORE STRENGTH, HIP EXTERNAL ROTATOR MUSCLE STRENGTH, AND STAR EXCURSION BALANCE TEST PERFORMANCE IN FEMALE LACROSSE PLAYERS

    PubMed Central

    Gordon, Angela T.; Ambegaonkar, Jatin P.; Caswell, Shane V.

    2013-01-01

    Purpose/Background: Female athletes have high rates of lower extremity (LE) injuries. Core strength (CS) and hip external rotator (HER) strength have been suggested to be factors that influence LE injury risk. Better balance has also been shown to decrease LE injury risk. Still, little research has examined whether core strength and hip muscle strength can influence LE balance. Therefore the purpose of the current study was to examine the relationships between core strength, hip ER strength and lower extremity balance as measured by the Star Excursion Balance Test (SEBT). Methods: CS was examined via the bent knee lowering test (BKLT) (grades 1‐5). Hip external rotator (HER) strength was measured singularly (HERL and HERR and combined (HERCOM) assessed via hand held dynamometry (reported in Newtons), and balance assessed via the SEBT expressed as % leg length, bilaterally in the postero‐medial, postero‐lateral, anterior directions and as a combined score (SEBTCOM). All outcomes were assessed in 45 female lacrosse players (16.0 ± 5.9 yrs, 65.1 ± 2.4 cm, 57.3 ± 7.4 kgs, experience=5.9 ± 2.9 yrs). Pearson product‐moment correlations examined relationships between the BKLT, HER and SEBT. Linear regression analyses examined possible influences of CS and HER on balance (p ≤ .05). Results: SEBTCOM was not correlated with BKLT [r(45)=–.20, p=.18] or HERCOM [r(45)=.20, p=.18]. There was no correlation between HER strength and CS (BKLT) [r(45)=.20, p=.20]. Overall scores on the BKLT were not correlated with any of the three balance SEBT scores. HERL [r(45)=.36, p=.02] and HERR [r(45)=.30, p=.05] were moderately positively correlated with left posteromedial SEBT direction. HERCOM and BKLT did not predict overall SEBTCOM balance scores (r2=.068, p=.23). Conclusions: BKLT scores and combined HER strength did not correlate with LE balance, as measured by the SEBT, in female lacrosse players. However, HER strength of both the left and right LE's (singularly) was

  13. Rotation of the external genitalia in male Phlebotomine sand flies (Diptera, Psychodidae) in laboratory conditions and in captured specimens in Algarve, Portugal.

    PubMed

    Ferrolho, J; Maia, C; Gomes, J; Alves-Pires, C; Cristóvão, J M; Campino, L; Afonso, M O

    2015-10-01

    Protozoal parasites are the causative agents of many insect-borne infectious diseases worldwide with impact on human and animal health. Leishmaniasis is caused by Leishmania spp. and transmitted by female Phlebotomine sand flies. In Portugal, two species of Phlebotomus (Larroussius), namely Phlebotomus perniciosus and Phlebotomus ariasi are the proven vectors of Leishmania infantum. Phlebotomine females and males rest and breed in the same sites; and these locations can be predicted according to the male external genitalia maturation. Therefore, this study aimed to determine the timing of complete rotation of the male external genitalia in laboratory conditions and to characterize the external genitalia rotation in field captured males to predict the male and female sand fly breeding and resting sites. This knowledge can be applied in the design and implementation of integrated sand fly control strategies targeting these sites.

  14. Enhanced Raman sensitivity using an actively stabilized external resonator

    NASA Astrophysics Data System (ADS)

    Taylor, David J.; Glugla, Manfred; Penzhorn, Ralf-Dieter

    2001-04-01

    An enhancement up to 250-fold in laser Raman signals for real-time gas analysis has been achieved within an actively stabilized external resonator (ASER), whose length is actively matched to the single-frequency excitation laser using the Pound-Drever technique. With the Raman cell present, enhancements up to 50-fold are achieved, and the resulting detection limit for hydrogen in ambient-pressure gas mixtures is about ten parts-per-million in a 1 min analysis period at unity signal-to-noise ratio. Based upon the recent development of a fiber-pumped Nd:YVO4 laser with single-frequency output exceeding 5 W at 532 nm, this highly sensitive instrument is applied to detection of tritiated gases, wherein the compactness and low heat of this laser head permit placing the entire optical system, including laser head, charge coupled Raman detector, and ASER, within the glove box necessary for secondary containment of tritium, thereby accomplishing a robust, highly sensitive Raman analytical system for hazardous substances.

  15. Deriving stellar inclination of slow rotators using stellar activity signal

    NASA Astrophysics Data System (ADS)

    Dumusque, Xavier

    2015-01-01

    Stellar inclination is an important parameter for many astrophysical studies. In the context of exoplanets, this allows us to derive the true obliquity of a system if the projected stellar spin-planetary orbit angle can measured via the Rossiter-Mclaughlin effect. Although different techniques allow us to estimate stellar inclination for fast rotators, it becomes much more difficult when stars are rotating slower than 2-2.5 km.s-1. By using the new activity simulation SOAP 2.0 that can reproduce the photometric and spectroscopic variations induced by stellar activity, we are able to fit the activity variation of solar-type stars and derive their inclination. The case of the equator-on star HD189733 will be presented, as well as the case of Alpha Centauri B, which present an inclination of 45+9-19 degrees, implying that the earth-mass orbiting planet is not transiting if aligned with its host star. Other exemples will also demonstrate the power of the technique, that can infer a stellar inclination, even for slow rotators like Alpha Centauri B, that present a projected rotational velocity smaller than 1.15 km.s-1. In addition, the SOAP 2.0 simulation can be used to correct for the effect of activity when one major active region is dominating the RV signal. This could enhance the detection of small mass exoplanets orbiting slightly active stars.This project is funded by ETAEARTH (European Union Seventh Framework Programme (FP7/2007-2013) under Grant Agreement n. 313014), a transnational collaboration between European countries and the US (the Swiss Space Office, the Harvard Origin of Life Initiative, the Scottish Universities Physics Alliance, the University of Geneva, the Smithsonian Astrophysical Observatory, the Italian National Astrophysical Institute, the University of St. Andrews, Queens University Belfast, and the University of Edinburgh) setup to optimize the synergy between space-and ground-based data whose scientific potential for the characterization of

  16. SOLAR ROTATION RATE DURING THE CYCLE 24 MINIMUM IN ACTIVITY

    SciTech Connect

    Antia, H. M.; Basu, Sarbani E-mail: sarbani.basu@yale.ed

    2010-09-01

    The minimum of solar cycle 24 is significantly different from most other minima in terms of its duration as well as its abnormally low levels of activity. Using available helioseismic data that cover epochs from the minimum of cycle 23 to now, we study the differences in the nature of the solar rotation between the minima of cycles 23 and 24. We find that there are significant differences between the rotation rates during the two minima. There are differences in the zonal-flow pattern too. We find that the band of fast rotating region close to the equator bifurcated around 2005 and recombined by 2008. This behavior is different from that during the cycle 23 minimum. By autocorrelating the zonal-flow pattern with a time shift, we find that in terms of solar dynamics, solar cycle 23 lasted for a period of 11.7 years, consistent with the result of Howe et al. (2009). The autocorrelation coefficient also confirms that the zonal-flow pattern penetrates through the convection zone.

  17. Early rehabilitation affects functional outcomes and activities of daily living after arthroscopic rotator cuff repair: a case report

    PubMed Central

    Shimo, Satoshi; Sakamoto, Yuta; Tokiyoshi, Akinari; Yamamoto, Yasuhiro

    2016-01-01

    [Purpose] The effect of early rehabilitation protocols after arthroscopic rotator cuff repair is currently unknown. We examined short-term effects of early rehabilitation on functional outcomes and activities of daily living after arthroscopic rotator cuff repair. [Subject and Methods] An 82-year-old male fell during a walk, resulting in a supraspinatus tear. Arthroscopic rotator cuff repair was performed using a single-row technique. He wore an abduction brace for 6 weeks after surgery. [Results] From day 1 after surgery, passive range of motion exercises, including forward flexion and internal and external rotation were performed twice per day. Starting at 6 weeks after surgery, active range of motion exercises and muscle strengthening exercises were introduced gradually. At 6 weeks after surgery, his active forward flexion was 150°, UCLA shoulder rating scale score was 34 points, and Quick Disabilities of the Arm, Shoulder, and Hand questionnaire disability/symptom score was 36 points. At 20 weeks after surgery, his active forward flexion was 120°, UCLA shoulder rating scale score was 34 points, and Quick Disabilities of the Arm, Shoulder, and Hand questionnaire disability/symptom score was 0 points. [Conclusion] These protocols are recommended to physical therapists during rehabilitation for arthroscopic rotator cuff repair to support rapid reintegration into activities of daily living. PMID:27064886

  18. Early rehabilitation affects functional outcomes and activities of daily living after arthroscopic rotator cuff repair: a case report.

    PubMed

    Shimo, Satoshi; Sakamoto, Yuta; Tokiyoshi, Akinari; Yamamoto, Yasuhiro

    2016-01-01

    [Purpose] The effect of early rehabilitation protocols after arthroscopic rotator cuff repair is currently unknown. We examined short-term effects of early rehabilitation on functional outcomes and activities of daily living after arthroscopic rotator cuff repair. [Subject and Methods] An 82-year-old male fell during a walk, resulting in a supraspinatus tear. Arthroscopic rotator cuff repair was performed using a single-row technique. He wore an abduction brace for 6 weeks after surgery. [Results] From day 1 after surgery, passive range of motion exercises, including forward flexion and internal and external rotation were performed twice per day. Starting at 6 weeks after surgery, active range of motion exercises and muscle strengthening exercises were introduced gradually. At 6 weeks after surgery, his active forward flexion was 150°, UCLA shoulder rating scale score was 34 points, and Quick Disabilities of the Arm, Shoulder, and Hand questionnaire disability/symptom score was 36 points. At 20 weeks after surgery, his active forward flexion was 120°, UCLA shoulder rating scale score was 34 points, and Quick Disabilities of the Arm, Shoulder, and Hand questionnaire disability/symptom score was 0 points. [Conclusion] These protocols are recommended to physical therapists during rehabilitation for arthroscopic rotator cuff repair to support rapid reintegration into activities of daily living. PMID:27064886

  19. Zeno inhibition of polarization rotation in an optically active medium

    NASA Astrophysics Data System (ADS)

    Gonzalo, Isabel; Porras, Miguel A.; Luis, Alfredo

    2015-07-01

    We describe an experiment in which the rotation of the polarization of light propagating in an optically active water solution of D-fructose tends to be inhibited by frequent monitoring whether the polarization remains unchanged. This is an example of the Zeno effect that has remarkable pedagogical interest because of its conceptual simplicity, easy implementation, low cost, and because the same the Zeno effect holds at classical and quantum levels. An added value is the demonstration of the Zeno effect beyond typical idealized assumptions in a practical setting with real polarizers.

  20. Various shrug exercises can change scapular kinematics and scapular rotator muscle activities in subjects with scapular downward rotation syndrome.

    PubMed

    Lee, Ji-Hyun; Cynn, Heon-Seock; Choi, Woo-Jeong; Jeong, Hyo-Jung; Yoon, Tae-Lim

    2016-02-01

    Scapular dyskinesis, characterized by scapular downward rotation syndrome (SDRS) affects scapula-humeral rhythm and results in shoulder dysfunction. Previous study has led to the recommendation of standard shrug exercise to contend with SDRS and strengthen the upper trapezius (UT) muscle. However, few researchers have examined which shrug exercise is most effective. The aim of this research was to compare scapular kinematic changes and scapular rotator muscles activity across three different shrug exercises in SDRS. The amounts of scapular downward rotation were measured by a caliper and the scapular upward rotation angle was measured using two digital inclinometers. Surface electromyography was used to measure EMG amplitude from the UT, lower trapezius (LT), serratus anterior (SA), and levator scapula (LS). Seventeen subjects with SDRS were recruited for this study. The subjects performed three shrug exercises with 30° shoulder abduction (preferred shrug, frontal shrug, and stabilization shrug). The stabilization shrug showed a significantly greater scapular upward rotation angle compared with the preferred shrug (P=0.004) and frontal shrug (P=0.006). The UT activity was significantly greater in the frontal shrug than in the preferred shrug (P=0.002). The UT/LS muscle activity ratio was also significantly greater in the frontal shrug than in the preferred shrug (P=0.004). The stabilization shrug should be preferred to enhance the upward rotation angle. In addition, the frontal shrug can be used as an effective method to increase UT activity and to decrease LS activity in SDRS. PMID:26625348

  1. Dynamics of an active magnetic particle in a rotating magnetic field.

    PubMed

    Cēbers, A; Ozols, M

    2006-02-01

    The motion of an active (self-propelling) particle with a permanent magnetic moment under the action of a rotating magnetic field is considered. We show that below a critical frequency of the external field the trajectory of a particle is a circle. For frequencies slightly above the critical point the particle moves on an approximately circular trajectory and from time to time jumps to another region of space. Symmetry of the particle trajectory depends on the commensurability of the field period and the period of the orientational motion of the particle. We also show how our results can be used to study the properties of naturally occurring active magnetic particles, so-called magnetotactic bacteria. PMID:16605340

  2. DOME-SHAPED EUV WAVES FROM ROTATING ACTIVE REGIONS

    SciTech Connect

    Selwa, M.; Poedts, S.; DeVore, C. R. E-mail: stefaan.poedts@wis.kuleuven.be

    2012-03-10

    Recent STEREO observations enabled the study of the properties of EUV waves in more detail. They were found to have a three-dimensional (3D) dome-shaped structure. We investigate, by means of 3D MHD simulations, the formation of EUV waves as the result of the interaction of twisted coronal magnetic loops. The numerical simulation is initialized with an idealized dipolar active region and is performed under coronal (low {beta}) conditions. A sheared rotational motion is applied to the central parts of both the positive and negative flux regions at the photosphere so that the flux tubes in between them become twisted. We find that the twisting motion results in a dome-shaped structure followed in space by a dimming and in time by an energy release (flare). The rotation of the sunspots is the trigger of the wave which initially consists of two fronts that later merge together. The resulting EUV wave propagates nearly isotropically on the disk and {approx}2 times faster in the upward direction. The initial stage of the evolution is determined by the driver, while later the wave propagates freely with a nearly Alfvenic speed.

  3. Incentive-Elicited Mesolimbic Activation and Externalizing Symptomatology in Adolescents

    ERIC Educational Resources Information Center

    Bjork, James M.; Chen, Gang; Smith, Ashley R.; Hommer, Daniel W.

    2010-01-01

    Background: Opponent-process theories of externalizing disorders (ExD) attribute them to some combination of overactive reward processing systems and/or underactive behavior inhibition systems. Reward processing has been indexed by recruitment of incentive-motivational neurocircuitry of the ventral striatum (VS), including nucleus accumbens…

  4. A note on the application of the Prigogine theorem to rotation of tokamak-plasmas in absence of external torques

    SciTech Connect

    Sonnino, Giorgio; Cardinali, Alessandro; Zonca, Fulvio; Sonnino, Alberto; Nardone, Pasquale; Steinbrecher, György

    2014-03-15

    Rotation of tokamak-plasmas, not at the mechanical equilibrium, is investigated using the Prigogine thermodynamic theorem. This theorem establishes that, for systems confined in rectangular boxes, the global motion of the system with barycentric velocity does not contribute to dissipation. This result, suitably applied to toroidally confined plasmas, suggests that the global barycentric rotations of the plasma, in the toroidal and poloidal directions, are pure reversible processes. In case of negligible viscosity and by supposing the validity of the balance equation for the internal forces, we show that the plasma, even not in the mechanical equilibrium, may freely rotate in the toroidal direction with an angular frequency, which may be higher than the neoclassical estimation. In addition, its toroidal rotation may cause the plasma to rotate globally in the poloidal direction at a speed faster than the expression found by the neoclassical theory. The eventual configuration is attained when the toroidal and poloidal angular frequencies reaches the values that minimize dissipation. The physical interpretation able to explain the reason why some layers of plasma may freely rotate in one direction while, at the same time, others may freely rotate in the opposite direction, is also provided. Invariance properties, herein studied, suggest that the dynamic phase equation might be of the second order in time. We then conclude that a deep and exhaustive study of the invariance properties of the dynamical and thermodynamic equations is the most correct and appropriate way for understanding the triggering mechanism leading to intrinsic plasma-rotation in toroidal magnetic configurations.

  5. A note on the application of the Prigogine theorem to rotation of tokamak-plasmas in absence of external torques.

    PubMed

    Sonnino, Giorgio; Cardinali, Alessandro; Sonnino, Alberto; Nardone, Pasquale; Steinbrecher, György; Zonca, Fulvio

    2014-03-01

    Rotation of tokamak-plasmas, not at the mechanical equilibrium, is investigated using the Prigogine thermodynamic theorem. This theorem establishes that, for systems confined in rectangular boxes, the global motion of the system with barycentric velocity does not contribute to dissipation. This result, suitably applied to toroidally confined plasmas, suggests that the global barycentric rotations of the plasma, in the toroidal and poloidal directions, are pure reversible processes. In case of negligible viscosity and by supposing the validity of the balance equation for the internal forces, we show that the plasma, even not in the mechanical equilibrium, may freely rotate in the toroidal direction with an angular frequency, which may be higher than the neoclassical estimation. In addition, its toroidal rotation may cause the plasma to rotate globally in the poloidal direction at a speed faster than the expression found by the neoclassical theory. The eventual configuration is attained when the toroidal and poloidal angular frequencies reaches the values that minimize dissipation. The physical interpretation able to explain the reason why some layers of plasma may freely rotate in one direction while, at the same time, others may freely rotate in the opposite direction, is also provided. Invariance properties, herein studied, suggest that the dynamic phase equation might be of the second order in time. We then conclude that a deep and exhaustive study of the invariance properties of the dynamical and thermodynamic equations is the most correct and appropriate way for understanding the triggering mechanism leading to intrinsic plasma-rotation in toroidal magnetic configurations.

  6. Spots, activity cycles, and differential rotation on cool stars

    NASA Astrophysics Data System (ADS)

    Alekseev, I. Yu.

    2005-01-01

    The first results are reported from a search for activity cycles in stars similar to the sun based on modelling their spotting with an algorithm developed at the Crimean Astrophysical Observatory. Of the more than thirty program stars, 10 manifested a cyclical variation in their central latitudes and total starspot area. The observed cycles have durations of 4-15 years, i.e., analogous to the 11 year Schwabe sunspot cycle. Most of the stars have a rough analog of the solar butterfly pattern, with a reduction in the average latitude of the spots as their area increases. A flip-flop effect during the epoch of the maximum average latitude is noted in a number of these objects (e.g., the analog LQ Hya of the young sun or the RS CVn-type variable V711 Tau), as well as a reduction in the photometric rotation period of a star as the spots drift toward the equator, an analog of the differential rotation effect in the sun. Unlike in the sun, the observed spot formation cycles do not correlate uniquely with other indicators of activity— chromospheric emission in the CaII HK lines (Be Cet, EK Dra, Dx Leo), H line emission (LQ Hya, VY Ari, EV Lac), or cyclical flare activity (EV Lac). In V833 Tau, BY Dra, EK Dra, and VY Ari short Schwabe cycles coexist with long cycles that are analogous to the Gleissberg solar cycle, in which the spotted area can approach half the entire area of the star.

  7. Association between meniscal tears and the peak external knee adduction moment and foot rotation during level walking in postmenopausal women without knee osteoarthritis: a cross-sectional study

    PubMed Central

    Davies-Tuck, Miranda L; Wluka, Anita E; Teichtahl, Andrew J; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Jones, Graeme; Ding, Changhai; Davis, Susan R; Cicuttini, Flavia M

    2008-01-01

    Introduction Meniscal injury is a risk factor for the development and progression of knee osteoarthritis, yet little is known about risk factors for meniscal pathology. Joint loading mediated via gait parameters may be associated with meniscal tears, and determining whether such an association exists was the aim of this study. Methods Three-dimensional Vicon gait analyses were performed on the dominant knee of 20 non-osteoarthritic women, and the peak external knee adduction moment during early and late stance was determined. The degree of foot rotation was also examined when the knee adductor moment peaked during early and late stance. Magnetic resonance imaging was used to determine the presence and severity of meniscal lesions in the dominant knee. Results The presence (P = 0.04) and severity (P = 0.01) of medial meniscal tears were positively associated with the peak external knee adduction moment during early stance while a trend for late stance was observed (P = 0.07). They were also associated with increasing degrees of internal foot rotation during late stance, independent of the magnitude of the peak external knee adduction moment occurring at that time (P = 0.03). During level walking among healthy women, the presence and severity of medial meniscal tears were positively associated with the peak external knee adduction moment. Moreover, the magnitude of internal foot rotation was associated with the presence and severity of medial meniscal lesions, independent of the peak knee adductor moment during late stance. Conclusion These data may suggest that gait parameters may be associated with meniscal damage, although longitudinal studies will be required to clarify whether gait abnormalities predate meniscal lesions, or vice versa, and therefore whether modification of gait patterns may be helpful. PMID:18492234

  8. Forced Magnetic Reconnection and Field Penetration of an Externally Applied Rotating Helical Magnetic Field in the TEXTOR Tokamak

    NASA Astrophysics Data System (ADS)

    Kikuchi, Y.; de Bock, M. F. M.; Finken, K. H.; Jakubowski, M.; Jaspers, R.; Koslowski, H. R.; Kraemer-Flecken, A.; Lehnen, M.; Liang, Y.; Matsunaga, G.; Reiser, D.; Wolf, R. C.; Zimmermann, O.

    2006-08-01

    The magnetic field penetration process into a magnetized plasma is of basic interest both for plasma physics and astrophysics. In this context special measurements on the field penetration and field amplification are performed by a Hall probe on the dynamic ergodic divertor (DED) on the TEXTOR tokamak and the data are interpreted by a two-fluid plasma model. It is observed that the growth of the forced magnetic reconnection by the rotating DED field is accompanied by a change of the plasma fluid rotation. The differential rotation frequency between the DED field and the plasma plays an important role in the process of the excitation of tearing modes. The momentum input from the rotating DED field to the plasma is interpreted by both a ponderomotive force at the rational surface and a radial electric field modified by an edge ergodization.

  9. Evaluation of Hip Internal and External Rotation Range of Motion as an Injury Risk Factor for Hip, Abdominal and Groin Injuries in Professional Baseball Players

    PubMed Central

    Ma, Richard; Zhou, Hanbing; Thompson, Matthew; Dawson, Courtney; Nguyen, Joseph; Coleman, Struan

    2015-01-01

    Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86). Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries. PMID:26793294

  10. Evaluation of Hip Internal and External Rotation Range of Motion as an Injury Risk Factor for Hip, Abdominal and Groin Injuries in Professional Baseball Players.

    PubMed

    Li, Xinning; Ma, Richard; Zhou, Hanbing; Thompson, Matthew; Dawson, Courtney; Nguyen, Joseph; Coleman, Struan

    2015-12-28

    Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86). Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries.

  11. Evaluation of Hip Internal and External Rotation Range of Motion as an Injury Risk Factor for Hip, Abdominal and Groin Injuries in Professional Baseball Players.

    PubMed

    Li, Xinning; Ma, Richard; Zhou, Hanbing; Thompson, Matthew; Dawson, Courtney; Nguyen, Joseph; Coleman, Struan

    2015-12-28

    Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip arc of motion compared to the positional players (N=86). Players with hip, groin, and hamstring injury also had decreased hip rotation arc when compared to the normal group. Overall, there is a correlation between decreased hip internal rotation and total arc of motion with hip, hamstring, and groin injuries. PMID:26793294

  12. A larger critical shoulder angle requires more rotator cuff activity to preserve joint stability.

    PubMed

    Viehöfer, Arnd F; Gerber, Christian; Favre, Philippe; Bachmann, Elias; Snedeker, Jess G

    2016-06-01

    Shoulders with rotator cuff tears (RCT) tears are associated with significantly larger critical shoulder angles (CSA) (RCT CSA = 38.2°) than shoulders without RCT (CSA = 32.9°). We hypothesized that larger CSAs increase the ratio of glenohumeral joint shear to joint compression forces, requiring substantially increased compensatory supraspinatus loads to stabilize the arm in abduction. A previously established three dimensional (3D) finite element (FE) model was used. Two acromion shapes mimicked the mean CSA of 38.2° found in patients with RCT and that of a normal CSA (32.9°). In a first step, the moment arms for each muscle segment were obtained for 21 different thoracohumeral abduction angles to simulate a quasi-static abduction in the scapular plane. In a second step, the muscle forces were calculated by minimizing the range of muscle stresses able to compensate an external joint moment caused by the arm weight. If the joint became unstable, additional force was applied by the rotator cuff muscles to restore joint stability. The model showed a higher joint shear to joint compressive force for the RCT CSA (38.2°) for thoracohumeral abduction angles between 40° and 90° with a peak difference of 23% at 50° of abduction. To achieve stability in this case additional rotator cuff forces exceeding physiological values were required. Our results document that a higher CSA tends to destabilize the glenohumeral joint such that higher than normal supraspinatus forces are required to maintain modeled stability during active abduction. This lends strong support to the concept that a high CSA can induce supraspinatus (SSP) overload. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:961-968, 2016. PMID:26572231

  13. Internalism, Active Externalism, and Nonconceptual Content: The Ins and Outs of Cognition

    ERIC Educational Resources Information Center

    Dartnall, Terry

    2007-01-01

    Active externalism (also known as the extended mind hypothesis) says that we use objects and situations in the world as external memory stores that we consult as needs dictate. This gives us economies of storage: We do not need to remember that Bill has blue eyes and wavy hair if we can acquire this information by looking at Bill. I argue for a…

  14. Sports Management Faculty External Grant-Writing Activities in the United States

    ERIC Educational Resources Information Center

    DeVinney, Timothy P.

    2012-01-01

    This study was conducted to fill a void in information, provide relevant, current data for faculty members related to external grant-writing activities related to the academic field of sport management and serve as a tool that may aid in the advancement of external grant-writing efforts within the field of sport management. All data is specific to…

  15. Solar wind and coronal rotation during an activity cycle

    NASA Astrophysics Data System (ADS)

    Pinto, Rui; Brun, Allan Sacha

    The properties of the solar wind flow are strongly affected by the time-varying strength and geometry of the global background magnetic field. The wind velocity and mass flux depend directly on the size and position of the wind sources at the surface, and on the geometry of the magnetic flux-tubes along which the wind flows. We address these problems by performing numerical simulations coupling a kinematic dynamo code (STELEM) evolve in a 2.5D axisymmetric coronal MHD code (DIP) covering an 11 yr activity cycle. The latitudinal distribution of the calculated wind velocities agrees with in-situ (ULYSSES, HELIO) and radio measurements (IPS). The transition from fast to slow wind flows can be explained in terms of the high overall flux-tube superradial expansion factors in the vicinities of coronal streamer boundaries. We found that the Alfvén radii and the global Sun's mass loss rate vary considerably throughout the cycle (by a factor 4.5 and 1.6, respectively), leading to strong temporal modulations of the global angular momentum flux and magnetic braking torque. The slowly varying magnetic topology introduces strong non-uniformities in the coronal rotation rate in the first few solar radii. Finally, we point out directions to assess the effects of surface transient phenomena on the global properties of the solar wind.

  16. ON THE ROLE OF ROTATING SUNSPOTS IN THE ACTIVITY OF SOLAR ACTIVE REGION NOAA 11158

    SciTech Connect

    Vemareddy, P.; Ambastha, A.; Maurya, R. A. E-mail: ambastha@prl.res.in

    2012-12-10

    We study the role of rotating sunspots in relation to the evolution of various physical parameters characterizing the non-potentiality of the active region (AR) NOAA 11158 and its eruptive events using the magnetic field data from the Helioseismic and Magnetic Imager (HMI) and multi-wavelength observations from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory. From the evolutionary study of HMI intensity and AIA channels, it is observed that the AR consists of two major rotating sunspots, one connected to a flare-prone region and another with coronal mass ejection (CME). The constructed space-time intensity maps reveal that the sunspots exhibited peak rotation rates coinciding with the occurrence of major eruptive events. Further, temporal profiles of twist parameters, namely, average shear angle, {alpha}{sub av}, {alpha}{sub best}, derived from HMI vector magnetograms, and the rate of helicity injection, obtained from the horizontal flux motions of HMI line-of-sight magnetograms, correspond well with the rotational profile of the sunspot in the CME-prone region, giving predominant evidence of rotational motion causing magnetic non-potentiality. Moreover, the mean value of free energy from the virial theorem calculated at the photospheric level shows a clear step-down decrease at the onset time of the flares revealing unambiguous evidence of energy release intermittently that is stored by flux emergence and/or motions in pre-flare phases. Additionally, distribution of helicity injection is homogeneous in the CME-prone region while in the flare-prone region it is not and often changes sign. This study provides a clear picture that both proper and rotational motions of the observed fluxes played significant roles in enhancing the magnetic non-potentiality of the AR by injecting helicity, twisting the magnetic fields and thereby increasing the free energy, leading to favorable conditions for the observed transient activity.

  17. Diagnostic accuracy of the gravity stress test and clinical signs in cases of isolated supination-external rotation-type lateral malleolar fractures.

    PubMed

    Nortunen, S; Flinkkilä, T; Lantto, I; Kortekangas, T; Niinimäki, J; Ohtonen, P; Pakarinen, H

    2015-08-01

    We prospectively assessed the diagnostic accuracy of the gravity stress test and clinical findings to evaluate the stability of the ankle mortise in patients with supination-external rotation-type fractures of the lateral malleolus without widening of the medial clear space. The cohort included 79 patients with a mean age of 44 years (16 to 82). Two surgeons assessed medial tenderness, swelling and ecchymosis and performed the external rotation (ER) stress test (a reference standard). A diagnostic radiographer performed the gravity stress test. For the gravity stress test, the positive likelihood ratio (LR) was 5.80 with a 95% confidence interval (CI) of 2.75 to 12.27, and the negative LR was 0.15 (95% CI 0.07 to 0.35), suggesting a moderate change from the pre-test probability. Medial tenderness, both alone and in combination with swelling and/or ecchymosis, indicated a small change (positive LR, 2.74 to 3.25; negative LR, 0.38 to 0.47), whereas swelling and ecchymosis indicated only minimal changes (positive LR, 1.41 to 1.65; negative LR, 0.38 to 0.47). In conclusion, when gravity stress test results are in agreement with clinical findings, the result is likely to predict stability of the ankle mortise with an accuracy equivalent to ER stress test results. When clinical examination suggests a medial-side injury, however, the gravity stress test may give a false negative result.

  18. Diagnostic accuracy of the gravity stress test and clinical signs in cases of isolated supination-external rotation-type lateral malleolar fractures.

    PubMed

    Nortunen, S; Flinkkilä, T; Lantto, I; Kortekangas, T; Niinimäki, J; Ohtonen, P; Pakarinen, H

    2015-08-01

    We prospectively assessed the diagnostic accuracy of the gravity stress test and clinical findings to evaluate the stability of the ankle mortise in patients with supination-external rotation-type fractures of the lateral malleolus without widening of the medial clear space. The cohort included 79 patients with a mean age of 44 years (16 to 82). Two surgeons assessed medial tenderness, swelling and ecchymosis and performed the external rotation (ER) stress test (a reference standard). A diagnostic radiographer performed the gravity stress test. For the gravity stress test, the positive likelihood ratio (LR) was 5.80 with a 95% confidence interval (CI) of 2.75 to 12.27, and the negative LR was 0.15 (95% CI 0.07 to 0.35), suggesting a moderate change from the pre-test probability. Medial tenderness, both alone and in combination with swelling and/or ecchymosis, indicated a small change (positive LR, 2.74 to 3.25; negative LR, 0.38 to 0.47), whereas swelling and ecchymosis indicated only minimal changes (positive LR, 1.41 to 1.65; negative LR, 0.38 to 0.47). In conclusion, when gravity stress test results are in agreement with clinical findings, the result is likely to predict stability of the ankle mortise with an accuracy equivalent to ER stress test results. When clinical examination suggests a medial-side injury, however, the gravity stress test may give a false negative result. PMID:26224832

  19. Experimental study on active structural acoustic control of rotating machinery using rotating piezo-based inertial actuators

    NASA Astrophysics Data System (ADS)

    Zhao, G.; Alujević, N.; Depraetere, B.; Pinte, G.; Swevers, J.; Sas, P.

    2015-07-01

    In this paper, two Piezo-Based Rotating Inertial Actuators (PBRIAs) are considered for the suppression of the structure-borne noise radiated from rotating machinery. As add-on devices, they can be directly mounted on a rotational shaft, in order to intervene as early as possible in the transfer path between disturbance and the noise radiating surfaces. A MIMO (Multi-Input-Multi-Output) form of the FxLMS control algorithm is employed to generate the appropriate actuation signals, relying on a linear interpolation scheme to approximate time varying secondary plants. The proposed active vibration control approach is tested on an experimental test bed comprising a rotating shaft mounted in a frame to which a noise-radiating plate is attached. The disturbance force is introduced by an electro-dynamic shaker. The experimental results show that when the shaft spins below 180 rpm, more than a 7 dB reduction can be achieved in terms of plate vibrations, along with a reduction in the same order of magnitude in terms of noise radiation.

  20. Cat vestibular neurons that exhibit different responses to active and passive yaw head rotations

    NASA Technical Reports Server (NTRS)

    Robinson, F. R.; Tomko, D. L.

    1987-01-01

    Neurons in the vestibular nuclei were recorded in alert cats during voluntary yaw rotations of the head and during the same rotations delivered with a turntable driven from a record of previous voluntary movements. During both voluntary and passive rotations, 35 percent (6/17) of neurons tested responded at higher rates or for a larger part of the movement during voluntary movements than during the same rotations delivered with the turntable. Neck sensory input was evaluated separately in many of these cells and can account qualitatively for the extra firing present during active movement.

  1. Rotation, activity, and stellar obliquities in a large uniform sample of Kepler solar analogs

    NASA Astrophysics Data System (ADS)

    Buzasi, Derek; Lezcano, Andy; Preston, Heather L.

    2016-10-01

    In this study, we undertook a deep photometric examination of a narrowly-defined sample of solar analogs in the Kepler field, with the goals of producing a uniform and statistically meaningful sample of such stars, comparing the properties of planet hosts to those of the general stellar population, and examining the behavior of rotation and photometric activity among stars with similar overall physical parameters. We successfully derived photometric activity indicators and rotation periods for 95 planet hosts (Kepler objects of interest [KOIs]) and 954 solar analogs without detected planets; 573 of these rotation periods are reported here for the first time. Rotation periods average roughly 20 d, but the distribution has a wide dispersion, with a tail extending to P > 35 d which appears to be inconsistent with published gyrochronological relations. We observed a weak rotation-activity relation for stars with rotation periods less than about 12 d; for slower rotators, the relation is dominated by scatter. However, we are able to state that the solar activity level derived from Virgo data is consistent with the majority of stars with similar rotation periods in our sample. Finally, our KOI sample is consistently approximately 0.3 dex more variable than our non-KOIs; we ascribe the difference to a selection effect due to low orbital obliquity in the planet-hosting stars and derive a mean obliquity for our sample of χ = 6+5°-6, similar to that seen in the solar system.

  2. Sex Differences in Mental Rotation and Cortical Activation Patterns: Can Training Change Them?

    ERIC Educational Resources Information Center

    Jausovec, Norbert; Jausovec, Ksenija

    2012-01-01

    In two experiments the neuronal mechanisms of sex differences in mental rotation were investigated. In Experiment 1 cortical activation was studied in women and men with similar levels of mental rotation ability (high, and average to low), who were equalized with respect to general intelligence. Sex difference in neuroelectric patterns of brain…

  3. Marital Conflict and Children's Externalizing Behavior: Interactions between Parasympathetic and Sympathetic Nervous System Activity

    ERIC Educational Resources Information Center

    El-Sheikh, Mona; Kouros, Chrystyna D.; Erath, Stephen; Cummings, E. Mark; Keller, Peggy; Staton, Lori

    2009-01-01

    Toward greater specificity in the prediction of externalizing problems in the context of interparental conflict, interactions between children's parasympathetic and sympathetic nervous system (PNS and SNS) activity were examined as moderators. PNS activity was indexed by respiratory sinus arrhythmia (RSA) and RSA reactivity (RSA-R) to lab…

  4. The effects of age and sex on mental rotation performance, verbal performance, and brain electrical activity.

    PubMed

    Roberts, Jonathan E; Bell, Martha Ann

    2002-05-01

    This study examined the effects of age and sex on mental rotation performance, verbal performance, and brain-wave activity. Thirty-two 8-year-olds (16 boys) and 32 college students (16 men) had EEG recorded at baseline and while performing four computerized tasks: a two-dimensional (2D) gingerbread man mental rotation, a 2D alphanumeric mental rotation, of three-dimensional (3D) basketball player mental rotation, and lexical decision making. Additionally, participants completed a paper- and pencil water level task and an oral verbal fluency task. On the 2D alphanumeric and 3D basketball player mental rotation tasks, men performed better than boys, but the performance of women and girls did not differ. On the water level task, men performed better than women whereas there was no difference between boys and girls. No sex differences were found on the 2D gingerbread man mental rotation, lexical decision-making, and verbal fluency tasks. EEG analyses indicated that men exhibited left posterior temporal activation during the 2D alphanumeric task and that men and boys both exhibited greater left parietal activation than women and girls during the 2D gingerbread man task. On the 3D basketball player mental rotation task, all participants exhibited greater activation of the right parietal area than the left parietal area. These data give insight into the brain activity and cognitive development changes that occur between childhood and adulthood.

  5. Electromechanical simulation and test of rotating systems with magnetic bearing or piezoelectric actuator active vibration control

    NASA Technical Reports Server (NTRS)

    Palazzolo, Alan B.; Tang, Punan; Kim, Chaesil; Manchala, Daniel; Barrett, Tim; Kascak, Albert F.; Brown, Gerald; Montague, Gerald; Dirusso, Eliseo; Klusman, Steve

    1994-01-01

    This paper contains a summary of the experience of the authors in the field of electromechanical modeling for rotating machinery - active vibration control. Piezoelectric and magnetic bearing actuator based control are discussed.

  6. External cardiac compression may be harmful in some scenarios of pulseless electrical activity.

    PubMed

    Hogan, T S

    2012-10-01

    Pulseless electrical activity occurs when organised or semi-organised electrical activity of the heart persists but the product of systemic vascular resistance and the increase in systemic arterial flow generated by the ejection of the left venticular stroke volume is not sufficient to produce a clinically detectable pulse. Pulseless electrical activity encompasses a very heterogeneous variety of severe circulatory shock states ranging in severity from pseudo-cardiac arrest to effective cardiac arrest. Outcomes of cardiopulmonary resuscitation for pulseless electrical activity are generally poor. Impairment of cardiac filling is the limiting factor to cardiac output in many scenarios of pulseless electrical activity, including extreme vasodilatory shock states. There is no evidence that external cardiac compression can increase cardiac output when impaired cardiac filling is the limiting factor to cardiac output. If impaired cardiac filling is the limiting factor to cardiac output and the heart is effectively ejecting all the blood returning to it, then external cardiac compression can only increase cardiac output if it increases venous return and cardiac filling. Repeated cardiac compression asynchronous with the patient's cardiac cycle and raised mean intrathoracic pressure due to chest compression can be expected to reduce rather than to increase cardiac filling and therefore to reduce rather than to increase cardiac output in such circumstances. The hypothesis is proposed that the performance of external cardiac compression will have zero or negative effect on cardiac output in pulseless electrical activity when impaired cardiac filling is the limiting factor to cardiac output. External cardiac compression may be both directly and indirectly harmful to significant sub-groups of patients with pulseless electrical activity. We have neither evidence nor theory to provide comfort that external cardiac compression is not harmful in many scenarios of pulseless

  7. Activity of Lipase and Chitinase Immobilized on Superparamagnetic Particles in a Rotational Magnetic Field

    PubMed Central

    Mizuki, Toru; Sawai, Miyuki; Nagaoka, Yutaka; Morimoto, Hisao; Maekawa, Toru

    2013-01-01

    We immobilize hydrolases such as lipase and chitinase on superparamagnetic particles, which are subjected to a rotational magnetic field, and measure the activities of the enzymes. We find that the activities of lipase and chitinase increase in the rotational magnetic field compared to those in the absence of a magnetic field and reach maximum at certain frequencies. The present methodology may well be utilized for the design and development of efficient micro reactors and micro total analysis systems (μ-TASs). PMID:23799111

  8. IUE observations of rapidly rotating low-mass stars in young clusters - The relation between chromospheric activity and rotation

    NASA Technical Reports Server (NTRS)

    Simon, Theodore

    1990-01-01

    If the rapid spindown of low-mass stars immediately following their arrival on the ZAMS results from magnetic braking by coronal winds, an equally sharp decline in their chromospheric emission may be expected. To search for evidence of this effect, the IUE spacecraft was used to observe the chromospheric Mg II emission lines of G-M dwarfs in the nearby IC 2391, Alpha Persei, Pleiades, and Hyades clusters. Similar observations were made of a group of X-ray-selected 'naked' T Tauri stars in Taurus-Auriga. The existence of a decline in activity cannot be confirmed from the resulting data. However, the strength of the chromospheric emission in the Mg II lines of the cluster stars is found to be correlated with rotation rate, being strongest for the stars with the shortest rotation periods and weakest for those with the longest periods. This provides indirect support for such an evolutionary change in activity. Chromospheric activity may thus be only an implicit function of age.

  9. Single Molecule Behavior of Inhibited and Active States of Escherichia coli ATP Synthase F1 Rotation*

    PubMed Central

    Sekiya, Mizuki; Hosokawa, Hiroyuki; Nakanishi-Matsui, Mayumi; Al-Shawi, Marwan K.; Nakamoto, Robert K.; Futai, Masamitsu

    2010-01-01

    ATP hydrolysis-dependent rotation of the F1 sector of the ATP synthase is a successive cycle of catalytic dwells (∼0.2 ms at 24 °C) and 120° rotation steps (∼0.6 ms) when observed under Vmax conditions using a low viscous drag 60-nm bead attached to the γ subunit (Sekiya, M., Nakamoto, R. K., Al-Shawi, M. K., Nakanishi-Matsui, M., and Futai, M. (2009) J. Biol. Chem. 284, 22401–22410). During the normal course of observation, the γ subunit pauses in a stochastic manner to a catalytically inhibited state that averages ∼1 s in duration. The rotation behavior with adenosine 5′-O-(3-thiotriphosphate) as the substrate or at a low ATP concentration (4 μm) indicates that the rotation is inhibited at the catalytic dwell when the bound ATP undergoes reversible hydrolysis/synthesis. The temperature dependence of rotation shows that F1 requires ∼2-fold higher activation energy for the transition from the active to the inhibited state compared with that for normal steady-state rotation during the active state. Addition of superstoichiometric ϵ subunit, the inhibitor of F1-ATPase, decreases the rotation rate and at the same time increases the duration time of the inhibited state. Arrhenius analysis shows that the ϵ subunit has little effect on the transition between active and inhibited states. Rather, the ϵ subunit confers lower activation energy of steady-state rotation. These results suggest that the ϵ subunit plays a role in guiding the enzyme through the proper and efficient catalytic and transport rotational pathway but does not influence the transition to the inhibited state. PMID:20974856

  10. PEA chloroplasts under clino-rotation: lipid peroxidation and superoxide dismutase activity

    NASA Astrophysics Data System (ADS)

    Baranenko, V. V.

    The lipid peroxidation (LP) intensity and the activity of the antioxidant enzyme superoxide dismutase (SOD) were studied in chloroplasts of pea (Pisum sativum L.) plants grown for 7 and 14 days under clino-rotation. An increase in LP levels in chloroplasts during both terms of clinorotation in comparison with stationary controls was documented. SOD activity increased in chloroplasts of plants that were clino-rotated for seven days. SOD has a significant protective effect by diminishing the availability of O2-. However, under more prolonged clino-rotation (14 days), SOD activity decreased but was still higher than in the control samples. In accordance with Selye's oxidative stress theory (Selye, 1956; modified by Leshem et al., 1998), plants that were clino-rotated for seven days are presumed to be in a stage of resistance while 14-day plants reached a stage of exhaustion.

  11. Supersaturation and activity-rotation relation in PMS stars: the young cluster h Persei

    NASA Astrophysics Data System (ADS)

    Argiroffi, C.; Caramazza, M.; Micela, G.; Sciortino, S.; Moraux, E.; Bouvier, J.; Flaccomio, E.

    2016-05-01

    Context. Several studies showed that the magnetic activity of late-type main-sequence (MS) stars is characterized by different regimes and that their activity levels are well described by the Rossby number, Ro, defined as the ratio between the rotational period Prot and the convective turnover time. Very young pre-main-sequence (PMS) stars show, similarly to MS stars, intense magnetic activity. However, they do not show clear activity-rotation trends, and it still debated which stellar parameters determine their magnetic activity levels. Aims: To bridge the gap between MS and PMS stars, we studied the activity-rotation relation in the young cluster h Persei, a ~13 Myr old cluster, that contains both fast and slow rotators. The cluster members have ended their accretion phase and have developed a radiative core. It therefore offers us the opportunity of studying the activity level of intermediate-age PMS stars with different rotational velocities, excluding any interactions with the circumstellar environment. Methods: We constrained the magnetic activity levels of h Per members by measuring their X-ray emission from a Chandra observation, while rotational periods were obtained previously in the framework of the MONITOR project. By cross-correlating these data, we collected a final catalog of 414 h Per members with known rotational period, effective temperature, and mass. In 169 of these, X-ray emission has also been detected. Results: We found that h Per members with 1.0 M⊙activity regimes: fast rotators clearly show supersaturation, while slower rotators have activity levels compatible to the non-saturated regime. At 13 Myr, h Per is therefore the youngest cluster showing activity-rotation regimes analogous to those of MS stars, indicating that at this age, magnetic field production is most likely regulated by the αΩ type dynamo. Moreover, we observed that supersaturation is better described by Prot than Ro, and that the

  12. A multiwavelength campaign of active stars with intermediate rotation rates

    NASA Technical Reports Server (NTRS)

    Dempsey, Robert C.; Neff, James E.; ONeal, Douglas; Olah, Katalin

    1995-01-01

    Near-to-simultaneous ultraviolet and visual spectroscopy of two moderate nu(sin i) RS CVn systems, V815 Herculis (nu(sin i) = 27 km s(exp -1)) and LM Pegasi (nu(sin i) = 24 km s(exp -1)), are presented along with contemporaneous UBV (RI)(sub c) - band photometry. These data were used to probe inhomogeneities in the chromospheres and photospheres, and the possible relationship between them. Both systems show evidence for rotationally modulated chromospheric emission, generally varying in antiphase to the photospheric brightness. A weak flare was observed at Mg II for V815 Her. In the case of IM Peg, we use photometry and spectra to estimate temperatures, sizes, and locations of photospheric spots. Further constraints on the spot temperature is provided by TiO observations. For IM Peg, the anticorrelation between chromospheric emission and brightness is discussed in the context of a possible solar-like spot cycle.

  13. The activation of the sodium pump in pig red blood cells by internal and external cations.

    PubMed

    Brand, S C; Whittam, R

    1985-05-30

    A study has been made with pig red blood cells of the activation of the sodium pump by internal and external cations. Cell Na and K concentrations were altered using a PCMBS cation loading procedure. The procedure was characterised for resultant ionic conditions, maintenance of ATP levels and fragility. The activation of the sodium pump by external K was measured in cells suspended in choline (Na-free) solutions. External Cs was used as a substitute for K and elicited lower rates of pump activity. Both the Vmax and apparent Km for 42K influx and 134Cs influx increased as internal Na concentration was raised (within the non-saturating range). Vmax/apparent Km ratios for cation influx were constant. Raising external Cs concentration exerted a similar influence on pump activation by internal Na: both the maximum pump velocity and the apparent Na-site dissociation constant (K'Na) increased. The results provide evidence for a transmembrane connection between cation binding sites on opposite faces of the membrane and are consistent with a consecutive model for the sodium pump in pig red blood cells. PMID:2581622

  14. Frontal Electroencephalogram Activation Asymmetry, Emotional Intelligence, and Externalizing Behaviors in 10-Year-Old Children

    ERIC Educational Resources Information Center

    Santesso, L. Diane; Dana, L. Reker; Schmidt, Louis A.; Segalowitz, Sidney J.

    2006-01-01

    The purpose of the present study was to examine the relations among resting frontal brain electrical activity (EEG) (hypothesized to reflect a predisposition to positive versus negative affect and ability to regulate emotions), emotional intelligence, and externalizing behaviors in a sample of non-clinical 10-year-old children. We found that boys…

  15. Does the World Leak into the Mind? Active Externalism, "Internalism" and Epistemology

    ERIC Educational Resources Information Center

    Dartnall, Terry

    2005-01-01

    One of the arguments for active externalism (also known as the extended mind thesis) is that if a process counts as cognitive when it is performed in the head, it should also count as cognitive when it is performed in the world. Consequently, mind extends into the world. I argue for a corollary: We sometimes perform actions in our heads that we…

  16. 48 CFR 9903.201-8 - Compliant accounting changes due to external restructuring activities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Compliant accounting changes due to external restructuring activities. 9903.201-8 Section 9903.201-8 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND...

  17. Gyrochronology of Low-mass Stars - Age-Rotation-Activity Relations for Young M Dwarfs

    NASA Astrophysics Data System (ADS)

    Kidder, Benjamin; Shkolnik, E.; Skiff, B.

    2014-01-01

    New rotation periods for 34 young <300 Myr), early-M dwarfs within 25 parsecs were measured using photometric data collected with telescopes at Lowell Observatory during 2012 and 2013. An additional 25 rotation periods for members of the same sample were found in the literature. Ages were derived from Hα and X-ray emission, lithium absorption, surface gravity, and kinematic association of members of known young moving groups (YMGs). We compared rotation periods with the estimated ages as well as indicators of magnetic activity, with the intention of strengthening age-rotation-activity relations and assessing the possible use of gyrochronology in young, low-mass stars. We compared ages and rotation periods of our target stars to cluster members spanning 1-600 Myr. Rotation periods at every age exhibit a large scatter, with values typically ranging from 0.2 to 15 days. This suggests that gyrochronology for individual field stars will not be possible without a better understanding of the underlying mechanisms that govern angular momentum evolution. Yet, on average, the data still support the predicted trends for spin-up during contraction and spin-down on the main sequence, with the turnover occurring at around 150 Myr for early Ms. This suggests that rotation period distributions can be helpful in evaluating the ages of coeval groups of stars. Many thanks to the National Science Foundation for their support through the Research Experience for Undergraduates Grant AST- 1004107.

  18. MOJAVE: MONITORING OF JETS IN ACTIVE GALACTIC NUCLEI WITH VLBA EXPERIMENTS. VIII. FARADAY ROTATION IN PARSEC-SCALE AGN JETS

    SciTech Connect

    Hovatta, Talvikki; Lister, Matthew L.; Aller, Margo F.; Aller, Hugh D.; Homan, Daniel C.; Kovalev, Yuri Y.

    2012-10-01

    We report observations of Faraday rotation measures for a sample of 191 extragalactic radio jets observed within the MOJAVE program. Multifrequency Very Long Baseline Array observations were carried out over 12 epochs in 2006 at four frequencies between 8 and 15 GHz. We detect parsec-scale Faraday rotation measures in 149 sources and find the quasars to have larger rotation measures on average than BL Lac objects. The median core rotation measures are significantly higher than in the jet components. This is especially true for quasars where we detect a significant negative correlation between the magnitude of the rotation measure and the de-projected distance from the core. We perform detailed simulations of the observational errors of total intensity, polarization, and Faraday rotation, and concentrate on the errors of transverse Faraday rotation measure gradients in unresolved jets. Our simulations show that the finite image restoring beam size has a significant effect on the observed rotation measure gradients, and spurious gradients can occur due to noise in the data if the jet is less than two beams wide in polarization. We detect significant transverse rotation measure gradients in four sources (0923+392, 1226+023, 2230+114, and 2251+158). In 1226+023 the rotation measure is for the first time seen to change sign from positive to negative over the transverse cuts, which supports the presence of a helical magnetic field in the jet. In this source we also detect variations in the jet rotation measure over a timescale of three months, which are difficult to explain with external Faraday screens and suggest internal Faraday rotation. By comparing fractional polarization changes in jet components between the four frequency bands to depolarization models, we find that an external purely random Faraday screen viewed through only a few lines of sight can explain most of our polarization observations, but in some sources, such as 1226+023 and 2251+158, internal

  19. [Agricultural activity and environmental externality: an analysis of the use of pesticides in the Brazilian savannah].

    PubMed

    Soares, Wagner Lopes; Porto, Marcelo Firpo

    2007-01-01

    This paper discusses the negative externalities associated with the intensive use of pesticides in the Brazilian savannah. These externalities are mainly related to impacts on the environment and on human health (rural workers and families, consumers), the costs of which end up being socialized. The externality considered in the present paper is of soil and water contamination by pesticides. The data source is the questionnaire of the Basic Municipal Information Research applied in 2003. Maps are used in order to associate contaminated areas with agricultural activity. Some risk factors associated with soil and water contamination by pesticides such as seasonal crop area, air pollution by burning and weed proliferation, were obtained through a logistic regression. The study concludes that the results can be helpful to formulate policies and aid in the design of regulating instruments and the definition of priority areas where preventive actions should be implemented.

  20. Effect of External Electric Field on Substrate Transport of a Secondary Active Transporter.

    PubMed

    Zhang, Ji-Long; Zheng, Qing-Chuan; Yu, Li-Ying; Li, Zheng-Qiang; Zhang, Hong-Xing

    2016-08-22

    Substrate transport across a membrane accomplished by a secondary active transporter (SAT) is essential to the normal physiological function of living cells. In the present research, a series of all-atom molecular dynamics (MD) simulations under different electric field (EF) strengths was performed to investigate the effect of an external EF on the substrate transport of an SAT. The results show that EF both affects the interaction between substrate and related protein's residues by changing their conformations and tunes the timeline of the transport event, which collectively reduces the height of energy barrier for substrate transport and results in the appearance of two intermediate conformations under the existence of an external EF. Our work spotlights the crucial influence of external EFs on the substrate transport of SATs and could provide a more penetrating understanding of the substrate transport mechanism of SATs. PMID:27472561

  1. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE

    PubMed Central

    Zahodne, Laura B.; Meyer, Oanh L.; Choi, Eunhee; Thomas, Michael L.; Willis, Sherry L.; Marsiske, Michael; Gross, Alden L.; Rebok, George W.; Parisi, Jeanine M.

    2015-01-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. PMID:26237116

  2. FAST ROTATION AND TRAILING FRAGMENTS OF THE ACTIVE ASTEROID P/2012 F5 (GIBBS)

    SciTech Connect

    Drahus, Michał; Waniak, Wacław; Tendulkar, Shriharsh; Agarwal, Jessica; Jewitt, David; Sheppard, Scott S.

    2015-03-20

    While having a comet-like appearance, P/2012 F5 (Gibbs) has an orbit native to the Main Asteroid Belt, and physically is a km-sized asteroid which recently (mid 2011) experienced an impulsive mass ejection event. Here we report new observations of this object obtained with the Keck II telescope on UT 2014 August 26. The data show previously undetected 200 m scale fragments of the main nucleus, and reveal a rapid nucleus spin with a rotation period of 3.24 ± 0.01 hr. The existence of large fragments and the fast nucleus spin are both consistent with rotational instability and partial disruption of the object. To date, many fast rotators have been identified among the minor bodies, which, however, do not eject detectable fragments at the present-day epoch, and also fragmentation events have been observed, but with no rotation period measured. P/2012 F5 is unique in that for the first time we detected fragments and quantified the rotation rate of one and the same object. The rapid spin rate of P/2012 F5 is very close to the spin rates of two other active asteroids in the Main Belt, 133P/Elst-Pizarro and (62412), confirming the existence of a population of fast rotators among these objects. But while P/2012 F5 shows impulsive ejection of dust and fragments, the mass loss from 133P is prolonged and recurrent. We believe that these two types of activity observed in the rapidly rotating active asteroids have a common origin in the rotational instability of the nucleus.

  3. Activity of an enzyme immobilized on superparamagnetic particles in a rotational magnetic field

    SciTech Connect

    Mizuki, Toru; Watanabe, Noriyuki; Nagaoka, Yutaka; Fukushima, Tadamasa; Morimoto, Hisao; Usami, Ron; Maekawa, Toru

    2010-03-19

    We immobilize {alpha}-amylase extracted from Bacillus Iicheniformis on the surfaces of superparamagnetic particles and investigate the effect of a rotational magnetic field on the enzyme's activity. We find that the activity of the enzyme molecules immobilized on superparamagnetic particles increases in the rotational magnetic field and reaches maximum at a certain frequency. We clarify the effect of the cluster structures formed by the superparamagnetic particles on the activity. Enzyme reactions are enhanced even in a tiny volume of solution using the present method, which is very important for the development of efficient micro reactors and micro total analysis systems ({mu}-TAS).

  4. Thermal Noise Reduction of Mechanical Oscillators by Actively Controlled External Dissipative Forces

    NASA Technical Reports Server (NTRS)

    Liang, Shoudan; Medich, David; Czajkowsky, Daniel M.; Sheng, Sitong; Yuan, Jian-Yang; Shao, Zhifeng

    1999-01-01

    We show that the thermal fluctuations of very soft mechanical oscillators, such as the cantilever in an atomic force microscope (AFM), can be reduced without changing the stiffness of the spring or having to lower the environment temperature. We derive a theoretical relationship between the thermal fluctuations of an oscillator and an actively external-dissipative force. This relationship is verified by experiments with an AFM cantilever where the external active force is coupled through a magnetic field. With simple instrumentation, we have reduced the thermal noise amplitude of the cantilever by a factor of 3.4, achieving an apparent temperature of 25 K with the environment at 295K. This active noise reduction approach can significantly improve the accuracy of static position or static force measurements in a number of practical applications.

  5. Piezoelectric pushers for active vibration control of rotating machinery

    NASA Technical Reports Server (NTRS)

    Palazzolo, Alan B.; Kascak, Albert F.

    1988-01-01

    The active control of rotordynamic vibrations and stability by magnetic bearings and electromagnetic shakers have been discussed extensively in the literature. These devices, though effective, are usually large in volume and add significant weight to the stator. The use of piezoelectric pushers may provide similar degrees of effectiveness in light, compact packages. Tests are currently being conducted with piezoelectric pusher-based active vibration control. Results from tests performed on NASA test rigs as preliminary verification of the related theory are presented.

  6. Crop rotation of flooded rice with upland maize impacts the resident and active methanogenic microbial community.

    PubMed

    Breidenbach, Björn; Blaser, Martin B; Klose, Melanie; Conrad, Ralf

    2016-09-01

    Crop rotation of flooded rice with upland crops is a common management scheme allowing the reduction of water consumption along with the reduction of methane emission. The introduction of an upland crop into the paddy rice ecosystem leads to dramatic changes in field conditions (oxygen availability, redox conditions). However, the impact of this practice on the archaeal and bacterial communities has scarcely been studied. Here, we provide a comprehensive study focusing on the crop rotation between flooded rice in the wet season and upland maize (RM) in the dry season in comparison with flooded rice (RR) in both seasons. The composition of the resident and active microbial communities was assessed by 454 pyrosequencing targeting the archaeal and bacterial 16S rRNA gene and 16S rRNA. The archaeal community composition changed dramatically in the rotational fields indicated by a decrease of anaerobic methanogenic lineages and an increase of aerobic Thaumarchaeota. Members of Methanomicrobiales, Methanosarcinaceae, Methanosaetaceae and Methanocellaceae were equally suppressed in the rotational fields indicating influence on both acetoclastic and hydrogenotrophic methanogens. On the contrary, members of soil crenarchaeotic group, mainly Candidatus Nitrososphaera, were higher in the rotational fields, possibly indicating increasing importance of ammonia oxidation during drainage. In contrast, minor effects on the bacterial community were observed. Acidobacteria and Anaeromyxobacter spp. were enriched in the rotational fields, whereas members of anaerobic Chloroflexi and sulfate-reducing members of Deltaproteobacteria were found in higher abundance in the rice fields. Combining quantitative polymerase chain reaction and pyrosequencing data revealed increased ribosomal numbers per cell for methanogenic species during crop rotation. This stress response, however, did not allow the methanogenic community to recover in the rotational fields during re-flooding and rice

  7. Spatial Rotation and Recognizing Emotions: Gender Related Differences in Brain Activity

    ERIC Educational Resources Information Center

    Jausovec, Norbert; Jausovec, Ksenija

    2008-01-01

    In three experiments, gender and ability (performance and emotional intelligence) related differences in brain activity--assessed with EEG methodology--while respondents were solving a spatial rotation tasks and identifying emotions in faces were investigated. The most robust gender related difference in brain activity was observed in the lower-2…

  8. Enhancing Potato System Sustainability: Crop Rotation Impacts on Soil Phosphatase Activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato is a species with a low efficiency of acquiring soil P. Rotation crops may potentially influence P uptake by potato by increasing soil organic acids, phosphatase activity, and microbial biomass. However, this kind of information is very limited. We measured the activities of acid phosphatase,...

  9. Analysis of neck muscle activity and comparison of head movement and body movement during rotational motion.

    PubMed

    Sirikantharajah, Shahini; Valter McConville, Kristiina M; Zolfaghari, Nika

    2015-08-01

    The neck is a very delicate part of the body that is highly prone to whiplash injuries, during jerk. A lot of the research relating to whiplash injuries performed to date has been tested in environments with linear motions and have mostly applied their work to car collisions. Whiplash injuries can also affect disabled individuals during falls, bed transfers, and while travelling in wheelchairs. The primary objective of this paper was to focus on neck and body behaviour during rotational motion, rather than linear motion which has been often associated with car collisions. This paper takes the current motion signal processing technique a step further by computing the differential between head and body motion. Neck electromyogram (EMG) and angular velocity data of the head and body were acquired simultaneously from 20 subjects, as they were rotated 45 degrees in the forward pitch plane, with and without visual input, in a motion simulator. The centre of rotation (COR) on the simulator was located behind the subject Results showed that neck muscle behaviour was affected by the forward rotations, as well as visual input. Anterior neck muscles were most active during forward rotations and trials including VR. Maximum effective muscle power and activity of 10.54% and 55.72 (mV/mV)·s were reached respectively. Furthermore, during forward rotations the motion profiles started off with dominance in body motion, followed by dominance in head motion.

  10. Analysis of neck muscle activity and comparison of head movement and body movement during rotational motion.

    PubMed

    Sirikantharajah, Shahini; Valter McConville, Kristiina M; Zolfaghari, Nika

    2015-08-01

    The neck is a very delicate part of the body that is highly prone to whiplash injuries, during jerk. A lot of the research relating to whiplash injuries performed to date has been tested in environments with linear motions and have mostly applied their work to car collisions. Whiplash injuries can also affect disabled individuals during falls, bed transfers, and while travelling in wheelchairs. The primary objective of this paper was to focus on neck and body behaviour during rotational motion, rather than linear motion which has been often associated with car collisions. This paper takes the current motion signal processing technique a step further by computing the differential between head and body motion. Neck electromyogram (EMG) and angular velocity data of the head and body were acquired simultaneously from 20 subjects, as they were rotated 45 degrees in the forward pitch plane, with and without visual input, in a motion simulator. The centre of rotation (COR) on the simulator was located behind the subject Results showed that neck muscle behaviour was affected by the forward rotations, as well as visual input. Anterior neck muscles were most active during forward rotations and trials including VR. Maximum effective muscle power and activity of 10.54% and 55.72 (mV/mV)·s were reached respectively. Furthermore, during forward rotations the motion profiles started off with dominance in body motion, followed by dominance in head motion. PMID:26737049

  11. Fast-Moving Bacteria Self-Organize into Active Two-Dimensional Crystals of Rotating Cells

    NASA Astrophysics Data System (ADS)

    Petroff, Alexander P.; Wu, Xiao-Lun; Libchaber, Albert

    2015-04-01

    We investigate a new form of collective dynamics displayed by Thiovulum majus, one of the fastest-swimming bacteria known. Cells spontaneously organize on a surface into a visually striking two-dimensional hexagonal lattice of rotating cells. As each constituent cell rotates its flagella, it creates a tornadolike flow that pulls neighboring cells towards and around it. As cells rotate against their neighbors, they exert forces on one another, causing the crystal to rotate and cells to reorganize. We show how these dynamics arise from hydrodynamic and steric interactions between cells. We derive the equations of motion for a crystal, show that this model explains several aspects of the observed dynamics, and discuss the stability of these active crystals.

  12. Rotation in a reversed field pinch with active feedback stabilization of resistive wall modes

    NASA Astrophysics Data System (ADS)

    Cecconello, M.; Menmuir, S.; Brunsell, P. R.; Kuldkepp, M.

    2006-09-01

    Active feedback stabilization of multiple resistive wall modes (RWMs) has been successfully proven in the EXTRAP T2R reversed field pinch. One of the features of plasma discharges operated with active feedback stabilization, in addition to the prolongation of the plasma discharge, is the sustainment of the plasma rotation. Sustained rotation is observed both for the internally resonant tearing modes (TMs) and the intrinsic impurity oxygen ions. Good quantitative agreement between the toroidal rotation velocities of both is found: the toroidal rotation is characterized by an acceleration phase followed, after one wall time, by a deceleration phase that is slower than in standard discharges. The TMs and the impurity ions rotate in the same poloidal direction with also similar velocities. Poloidal and toroidal velocities have comparable amplitudes and a simple model of their radial profile reproduces the main features of the helical angular phase velocity. RWMs feedback does not qualitatively change the TMs behaviour and typical phenomena such as the dynamo and the 'slinky' are still observed. The improved sustainment of the plasma and TMs rotation occurs also when feedback only acts on internally non-resonant RWMs. This may be due to an indirect positive effect, through non-linear coupling between TMs and RWMs, of feedback on the TMs or to a reduced plasma-wall interaction affecting the plasma flow rotation. Electromagnetic torque calculations show that with active feedback stabilization the TMs amplitude remains well below the locking threshold condition for a thick shell. Finally, it is suggested that active feedback stabilization of RWMs and current profile control techniques can be employed simultaneously thus improving both the plasma duration and its confinement properties.

  13. Periodicity Signatures of Lightcurves of Active Comets in Non-Principal-Axis Rotational States

    NASA Astrophysics Data System (ADS)

    Samarasinha, Nalin H.; Mueller, Beatrice E. A.; Barrera, Jose G.

    2016-10-01

    There are two comets (1P/Halley, 103P/Hartley 2) that are unambiguously in non-principal-axis (NPA) rotational states in addition to a few more comets that are candidates for NPA rotation. Considering this fact, and the ambiguities associated with how to accurately interpret the periodicity signatures seen in lightcurves of active comets, we have started an investigation to identify and characterize the periodicity signatures present in simulated lightcurves of active comets. We carried out aperture photometry of simulated cometary comae to generate model lightcurves and analyzed them with Fourier techniques to identify their periodicity signatures. These signatures were then compared with the input component periods of the respective NPA rotational states facilitating the identification of how these periodicity signatures are related to different component periods of the NPA rotation. Ultimately, we also expect this study to shed light on why only a small fraction of periodic comets is in NPA rotational states, whereas theory indicates a large fraction of them should be in NPA states (e.g., Jewitt 1999, EMP, 79, 35). We explore the parameter space with respect to different rotational states, different orientations for the total rotational angular momentum vector, and different locations on the nucleus for the source region(s). As for special cases, we also investigate potential NPA rotational states representative of comet 103P/Hartley2, the cometary target of the EPOXI mission. The initial results from our investigation will be presented at the meeting. The NASA DDAP Program supports this work through grant NNX15AL66G.

  14. Gemini and Keck Observations of Slowly Rotating, Bilobate Active Asteroid (300163)

    NASA Astrophysics Data System (ADS)

    Waniak, Waclaw; Drahus, Michal

    2016-10-01

    One of the most puzzling questions regarding Active Asteroids is the mechanism of their activation. While some Active Asteroids show protracted and often recurrent mass loss, consistent with seasonal ice sublimation, some other eject dust impulsively as a result of a catastrophic disruption (e.g. Jewitt et al. 2015, Asteroids IV, 221). It has been suggested that ice can be excavated from the cold near-surface interior by an impact (Hsieh & Jewitt 2006, Science 312, 561) or, for small objects susceptible to YORP torques, by near-critical spin rate (Sheppard & Trujillo 2014, AJ 149, 44). But impact and rapid spin can also cause a catastrophic disruption (e.g. Jewitt et al. 2015, Asteroids IV, 221). It therefore becomes apparent that the different types of mass loss observed in Active Asteroids can be best classified and understood based on the nucleus spin rates (Drahus et al. 2015, ApJL 802, L8), but unfortunately the rotation periods have been measured for a very limited number of these objects. With this in mind we have initiated a survey of light curves of small Active Asteroids on the largest ground-based optical telescopes. Here we present the results for (300163), also known as 288P and 2006 VW139, which is a small 2.6-km sized asteroid that exhibited a comet-like activity over 100 days in the second half of 2011 (Hsieh et al. 2012, ApJL 748, L15; Licandro et al. 2013, A&A 550, A17; Agarwal et al. 2016, AJ 151, 12). Using Keck/DEIMOS and Gemini/GMOS-S working in tandem on UT 2015 May 21–22 we have detected an inactive nucleus and measured a complete, dense, high-S/N rotational light curve. The light curve has a double-peaked period of 16 hours, an amplitude of 0.4 mag, and moderately narrow minima suggesting a bilobate or contact-binary shape. The long rotation period clearly demonstrates a non-rotational origin of activity of this object, consistent with an impact. Furthermore, among the five small Active Asteroids with known rotation periods (300163) is

  15. Lower rotation speed stimulates sympathetic activation during continuous-flow left ventricular assist device treatment.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro; Nitta, Daisuke; Fujino, Takeo; Inaba, Toshiro; Maki, Hisataka; Hatano, Masaru; Kinoshita, Osamu; Nawata, Kan; Kyo, Shunei; Ono, Minoru

    2015-03-01

    Although the suppression of sympathetic activity is an essential mission for the current heart failure treatment strategy, little is known about the relationship between the rotation speed setting and autonomic nervous activity during continuous-flow left ventricular assist device (LVAD) treatment. We evaluated 23 adult patients with sinus rhythm (36 ± 13 years) who had received continuous-flow LVAD and been followed at our institute between March 2013 and August 2014. Heart rate variability measurement was executed along with hemodynamic study at 3 rotation speeds (low, middle, and high) at 5 weeks after LVAD implantation. Lower rotation speed was associated with higher ratio of low-frequency over high-frequency spectral level (LF/HF), representing enhanced sympathetic activation (p < 0.05 by repeated analyses of variance). Among hemodynamic parameters, cardiac index was exclusively associated with LFNU = LF/(LF + HF), representing relative sympathetic activity over parasympathetic one (p < 0.05). After 6 months LVAD support at middle rotation speed, 19 patients with higher LFNU eventually had higher plasma levels of B-type natriuretic peptide and achieved less LV reverse remodeling. A logistic regression analysis demonstrated that lower LFNU was significantly associated with improvement of LV reverse remodeling (p = 0.021, odds ratio 0.903) with a cut-off level of 55 % calculated by the ROC analysis (AUC 0.869). In conclusion, autonomic activity can vary in various rotation speeds. Patients with higher LFNU may better be controlled at higher rotation speed with the view point to suppress sympathetic activity and achieve LV reverse remodeling.

  16. External kink modes as a model for MHD activity associated with ELMs

    SciTech Connect

    Manickam, J.

    1992-01-01

    Tokamak plasmas in the high confinement mode of operation are known to exhibit edge localized activity referred to as ELMs. A model is proposed for the underlying cause in terms of the external kink mode. The build up of the current density near the plasma edge is shown to decrease the shear in the safety-factor, q, profile and lead to destabilization of the kink mode. The role of the plasma geometry and equilibrium profiles is discussed.

  17. Interactive modeling activities in the classroom—rotational motion and smartphone gyroscopes

    NASA Astrophysics Data System (ADS)

    Pörn, Ray; Braskén, Mats

    2016-11-01

    The wide-spread availability of smartphones makes them a valuable addition to the measurement equipment in both the physics classroom and the instructional laboratory, encouraging an active interaction between measurements and modeling activities. In this paper we illustrate this interaction by making use of the internal gyroscope of a smartphone to study and measure the rotational dynamics of objects rotating about a fixed axis. The workflow described in this paper has been tested in a classroom setting and found to encourage an exploratory approach to both data collecting and modeling.

  18. Dynamical quorum sensing and clustering dynamics in a population of spatially distributed active rotators

    NASA Astrophysics Data System (ADS)

    Sakaguchi, Hidetsugu; Maeyama, Satomi

    2013-02-01

    A model of clustering dynamics is proposed for a population of spatially distributed active rotators. A transition from excitable to oscillatory dynamics is induced by the increase of the local density of active rotators. It is interpreted as dynamical quorum sensing. In the oscillation regime, phase waves propagate without decay, which generates an effectively long-range interaction in the clustering dynamics. The clustering process becomes facilitated and only one dominant cluster appears rapidly as a result of the dynamical quorum sensing. An exact localized solution is found to a simplified model equation, and the competitive dynamics between two localized states is studied numerically.

  19. Broad-line active galactic nuclei rotate faster than narrow-line ones.

    PubMed

    Kollatschny, Wolfram; Zetzl, Matthias

    2011-02-17

    The super-massive black holes of 10(6)M(⊙) to 10(9)M(⊙) that reside in the nuclei of active galaxies (AGN) are surrounded by a region emitting broad lines, probably associated with an accretion disk. The diameters of the broad-line regions range from a few light-days to more than a hundred light-days, and cannot be resolved spatially. The relative significance of inflow, outflow, rotational or turbulent motions in the broad-line regions as well as their structure (spherical, thin or thick accretion disk) are unknown despite intensive studies over more than thirty years. Here we report a fundamental relation between the observed emission linewidth full-width at half-maximum (FWHM) and the emission line shape FWHM/σ(line) in AGN spectra. From this relation we infer that the predominant motion in the broad-line regions is Keplerian rotation in combination with turbulence. The geometry of the inner region varies systematically with the rotation velocity: it is flattest for the fast-rotating broad-line objects, whereas slow-rotating narrow-line AGN have a more spherical structure. Superimposed is the trend that the line-emitting region becomes geometrically thicker towards the centre within individual galaxies. Knowing the rotational velocities, we can derive the central black-hole masses more accurately; they are two to ten times smaller than has been estimated previously.

  20. Spectral characterization and differential rotation study of active CoRoT stars

    NASA Astrophysics Data System (ADS)

    Nagel, E.; Czesla, S.; Schmitt, J. H. M. M.

    2016-05-01

    The CoRoT space telescope observed nearly 160 000 light curves. Among the most outstanding is that of the young, active planet host star CoRoT-2A. In addition to deep planetary transits, the light curve of CoRoT-2A shows strong rotational variability and a superimposed beating pattern. To study the stars that produce such an intriguing pattern of photometric variability, we identified a sample of eight stars with rotation periods between 0.8 and 11 days and photometric variability amplitudes of up to 7.5%, showing a similar CoRoT light curve. We also obtained high-resolution follow-up spectroscopy with TNG/SARG and carried out a spectral analysis with SME and MOOG. We find that the color dependence of the light curves is consistent with rotational modulation due to starspots and that latitudinal differential rotation provides a viable explanation for the light curves, although starspot evolution is also expected to play an important role. Our MOOG and SME spectral analyses provide consistent results, showing that the targets are dwarf stars with spectral types between F and mid-K. Detectable Li i absorption in four of the targets confirms a low age of 100-400 Myr also deduced from gyrochronology. Our study indicates that the photometric beating phenomenon is likely attributable to differential rotation in fast-rotating stars with outer convection zones.

  1. Controlled Activation of Protein Rotational Dynamics Using Smart Hydrogel Tethering

    SciTech Connect

    Beech, Brenda M.; Xiong, Yijia; Boschek, Curt B.; Baird, Cheryl L.; Bigelow, Diana J.; Mcateer, Kathleen; Squier, Thomas C.

    2014-09-05

    Stimulus-responsive hydrogel materials that stabilize and control protein dynamics have the potential to enable a range of applications to take advantage of the inherent specificity and catalytic efficiencies of proteins. Here we describe the modular construction of a hydrogel using an engineered calmodulin (CaM) within a polyethylene glycol (PEG) matrix that involves the reversible tethering of proteins through an engineered CaM-binding sequence. For these measurements, maltose binding protein (MBP) was isotopically labeled with [13C] and [15N], permitting dynamic structural measurements using TROSY-HSQC NMR spectroscopy. Upon initial formation of hydrogels protein dynamics are suppressed, with concomitant increases in protein stability. Relaxation of the hydrogel matrix following transient heating results in the activation of protein dynamics and restoration of substrate-induced large-amplitude domain motions necessary for substrate binding.

  2. The changing rotation period of comet 67P/Churyumov-Gerasimenko controlled by its activity

    NASA Astrophysics Data System (ADS)

    Keller, H. U.; Mottola, S.; Skorov, Y.; Jorda, L.

    2015-07-01

    Context. The ESA Rosetta spacecraft has been orbiting the nucleus of comet 67P/Churyumov-Gerasimenko since August 2014. The rotation axis of the irregularly shaped nucleus has a large obliquity (52°) and is oriented such that the southern hemisphere is insolated during perihelion. Aims: We calculate the change in the rotation period as a function of the cometary orbital position due to forces exerted by cometary activity. Methods: We used a detailed shape model of 67P with >105 facets. We calculated the efficiency of the facets to exert a torque based on their radial distance from the center of mass and their orientation. We applied our thermal model to calculate the diurnal water-ice sublimation rate from each facet. The reaction force per facet combined with its torque efficiency creates a torque and changes the angular momentum. The component of the torque parallel to the spin axis changes the rotation period. Results: Our model shows that the rotation period increases slightly during the approach of the comet to the Sun. It reaches a maximum shortly before equinox and drops rapidly during perihelion passage. The magnitude of the change depends on the actual sublimation rates. The change in sign mainly depends on the shape of the nucleus and not much on the sublimation variation. The roughness of the nucleus has little influence. Conclusions: For the given geometry of the rotation axis, the change in the rotation period is mainly influenced by the sublimation activity of the irregular shape of the nucleus. The rotation period increases until shortly before equinox in early May 2015, in good agreement with observations, and will then become shorter rapidly.

  3. Active control of counter-rotating open rotor interior noise in a Dornier 728 experimental aircraft

    NASA Astrophysics Data System (ADS)

    Haase, Thomas; Unruh, Oliver; Algermissen, Stephan; Pohl, Martin

    2016-08-01

    The fuel consumption of future civil aircraft needs to be reduced because of the CO2 restrictions declared by the European Union. A consequent lightweight design and a new engine concept called counter-rotating open rotor are seen as key technologies in the attempt to reach this ambitious goals. Bearing in mind that counter-rotating open rotor engines emit very high sound pressures at low frequencies and that lightweight structures have a poor transmission loss in the lower frequency range, these key technologies raise new questions in regard to acoustic passenger comfort. One of the promising solutions for the reduction of sound pressure levels inside the aircraft cabin are active sound and vibration systems. So far, active concepts have rarely been investigated for a counter-rotating open rotor pressure excitation on complex airframe structures. Hence, the state of the art is augmented by the preliminary study presented in this paper. The study shows how an active vibration control system can influence the sound transmission of counter-rotating open rotor noise through a complex airframe structure into the cabin. Furthermore, open questions on the way towards the realisation of an active control system are addressed. In this phase, an active feedforward control system is investigated in a fully equipped Dornier 728 experimental prototype aircraft. In particular, the sound transmission through the airframe, the coupling of classical actuators (inertial and piezoelectric patch actuators) into the structure and the performance of the active vibration control system with different error sensors are investigated. It can be shown that the active control system achieves a reduction up to 5 dB at several counter-rotating open rotor frequencies but also that a better performance could be achieved through further optimisations.

  4. Assessment of the Antimicrobial Activity of Algae Extracts on Bacteria Responsible of External Otitis

    PubMed Central

    Pane, Gianluca; Cacciola, Gabriele; Giacco, Elisabetta; Mariottini, Gian Luigi; Coppo, Erika

    2015-01-01

    External otitis is a diffuse inflammation around the external auditory canal and auricle, which is often occurred by microbial infection. This disease is generally treated using antibiotics, but the frequent occurrence of antibiotic resistance requires the development of new antibiotic agents. In this context, unexplored bioactive natural candidates could be a chance for the production of targeted drugs provided with antimicrobial activity. In this paper, microbial pathogens were isolated from patients with external otitis using ear swabs for over one year, and the antimicrobial activity of the two methanol extracts from selected marine (Dunaliella salina) and freshwater (Pseudokirchneriella subcapitata) microalgae was tested on the isolated pathogens. Totally, 114 bacterial and 11 fungal strains were isolated, of which Staphylococcus spp. (28.8%) and Pseudomonas aeruginosa (P. aeruginosa) (24.8%) were the major pathogens. Only three Staphylococcus aureus (S. aureus) strains and 11 coagulase-negative Staphylococci showed resistance to methicillin. The two algal extracts showed interesting antimicrobial properties, which mostly inhibited the growth of isolated S. aureus, P. aeruginosa, Escherichia coli, and Klebsiella spp. with MICs range of 1.4 × 109 to 2.2 × 1010 cells/mL. These results suggest that the two algae have potential as resources for the development of antimicrobial agents. PMID:26492256

  5. Interaction of adrenocortical activity and autonomic arousal on children's externalizing and internalizing behavior problems.

    PubMed

    Chen, Frances R; Raine, Adrian; Soyfer, Liana; Granger, Douglas A

    2015-01-01

    The psychobiology of stress involves two major components, the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS). Research has revealed the association between behavior problems and the psychobiology of stress, yet findings are inconsistent and few studies have addressed the moderate correlations between behavior problems. This study examines the individual and interactive effects of HPA and ANS on child behavior problems while taking into account the comorbidity of externalizing and internalizing problems. Four saliva samples were collected from each participant in a community sample (N = 429; aged 11-12 years; 50.49 % male), which were assayed for cortisol (HPA) and alpha-amylase, sAA (ANS). Children's behavior problems were assessed using parent-report and self-report versions of the Child Behavior Checklist. Latent variables were constructed to represent trait-like individual differences in cortisol and sAA. Low levels of HPA axis activity were associated with higher levels of both externalizing and internalizing problems, but only among children with low ANS arousal. The association between externalizing and internalizing problems diminished to non-significant after taking into account the influence of HPA axis activity and ANS arousal, which suggests that the psychobiology of stress explains a fair proportion of comorbidity of behavior problems. The findings support that interaction between HPA axis and ANS functioning has potential to clarify prior mixed findings and advance our understanding of the child behavior problems.

  6. Model for growth hormone receptor activation based on subunit rotation within a receptor dimer

    SciTech Connect

    Brown, Richard J.; Adams, Julian J.; Pelekanos, Rebecca A.; Wan, Yu; McKinstry, William J.; Palethorpe, Kathryn; Seeber, Ruth M.; Monks, Thea A.; Eidne, Karin A.; Parker, Michael W.; Waters, Michael J.

    2010-07-13

    Growth hormone is believed to activate the growth hormone receptor (GHR) by dimerizing two identical receptor subunits, leading to activation of JAK2 kinase associated with the cytoplasmic domain. However, we have reported previously that dimerization alone is insufficient to activate full-length GHR. By comparing the crystal structure of the liganded and unliganded human GHR extracellular domain, we show here that there is no substantial change in its conformation on ligand binding. However, the receptor can be activated by rotation without ligand by inserting a defined number of alanine residues within the transmembrane domain. Fluorescence resonance energy transfer (FRET), bioluminescence resonance energy transfer (BRET) and coimmunoprecipitation studies suggest that receptor subunits undergo specific transmembrane interactions independent of hormone binding. We propose an activation mechanism involving a relative rotation of subunits within a dimeric receptor as a result of asymmetric placement of the receptor-binding sites on the ligand.

  7. Integrated failure detection and management for the Space Station Freedom external active thermal control system

    NASA Technical Reports Server (NTRS)

    Mesloh, Nick; Hill, Tim; Kosyk, Kathy

    1993-01-01

    This paper presents the integrated approach toward failure detection, isolation, and recovery/reconfiguration to be used for the Space Station Freedom External Active Thermal Control System (EATCS). The on-board and on-ground diagnostic capabilities of the EATCS are discussed. Time and safety critical features, as well as noncritical failures, and the detection coverage for each provided by existing capabilities are reviewed. The allocation of responsibility between on-board software and ground-based systems, to be shown during ground testing at the Johnson Space Center, is described. Failure isolation capabilities allocated to the ground include some functionality originally found on orbit but moved to the ground to reduce on-board resource requirements. Complex failures requiring the analysis of multiple external variables, such as environmental conditions, heat loads, or station attitude, are also allocated to ground personnel.

  8. Task Rotation: Strategies for Differentiating Activities and Assessments by Learning Style. A Strategic Teacher PLC Guide

    ERIC Educational Resources Information Center

    Silver, Harvey; Moirao, Daniel; Jackson, Joyce

    2011-01-01

    One of the hardest jobs in teaching is to differentiate learning activities and assessments to your students' learning styles. But you and your colleagues can learn how to do this together when each of you has this guide to the Task Rotation strategy from our ultimate guide to teaching strategies, "The Strategic Teacher". Use the guide in your…

  9. The use of gravity or manual-stress radiographs in the assessment of supination-external rotation fractures of the ankle.

    PubMed

    Schock, H J; Pinzur, M; Manion, L; Stover, M

    2007-08-01

    Supination-external rotation (SER) fractures of the ankle may present with a medial ligamentous injury that is not apparent on the initial radiographs. A cadaver gravity-stress view has been described, but the manual-stress view is considered to be the examination of choice for the diagnosis of medial injuries. We prospectively compared the efficacy of these two examinations. We undertook both examinations in 29 patients with SER fractures. Of these, 16 (55%) were stress-positive, i.e. and had widening of the medial clear space of > 4 mm with a mean medial clear space of 6.09 mm (4.4 to 8.1) on gravity-stress and 5.81 mm (4.0 to 8.2) on manual-stress examination, and 13 patients (45%) were stress-negative with a mean medial clear space of 3.91 mm (3.3 to 5.1) and 3.61 mm (2.6 to 4.5) on examination of gravity- and manual-stress respectively. The mean absolute visual analgoue scale score for discomfort in the examination of gravity stress was 3.45 (1 to 6) and in the manual-stress procedure 6.14 (3 to 10). We have shown that examination of gravity-stress is as reliable and perceived as more comfortable than that of manual stress. We recommend using it as the initial diagnostic screening examination for the detection of occult medial ligamentous injuries in SER fractures of the ankle.

  10. Variation in human cancer cell external phosphatidylserine is regulated by flippase activity and intracellular calcium

    PubMed Central

    Vallabhapurapu, Subrahmanya D.; Blanco, Víctor M.; Sulaiman, Mahaboob K.; Vallabhapurapu, Swarajya Lakshmi; Chu, Zhengtao; Franco, Robert S.; Qi, Xiaoyang

    2015-01-01

    Viable cancer cells expose elevated levels of phosphatidylserine (PS) on the exoplasmic face of the plasma membrane. However, the mechanisms leading to elevated PS exposure in viable cancer cells have not been defined. We previously showed that externalized PS may be used to monitor, target and kill tumor cells. In addition, PS on tumor cells is recognized by macrophages and has implications in antitumor immunity. Therefore, it is important to understand the molecular details of PS exposure on cancer cells in order to improve therapeutic targeting. Here we explored the mechanisms regulating the surface PS exposure in human cancer cells and found that differential flippase activity and intracellular calcium are the major regulators of surface PS exposure in viable human cancer cells. In general, cancer cell lines with high surface PS exhibited low flippase activity and high intracellular calcium, whereas cancer cells with low surface PS exhibited high flippase activity and low intracellular calcium. High surface PS cancer cells also had higher total cellular PS than low surface PS cells. Together, our results indicate that the amount of external PS in cancer cells is regulated by calcium dependent flippase activity and may also be influenced by total cellular PS. PMID:26462157

  11. Active site coupling in Plasmodium falciparum GMP synthetase is triggered by domain rotation.

    PubMed

    Ballut, Lionel; Violot, Sébastien; Shivakumaraswamy, Santosh; Thota, Lakshmi Prasoona; Sathya, Manu; Kunala, Jyothirmai; Dijkstra, Bauke W; Terreux, Raphaël; Haser, Richard; Balaram, Hemalatha; Aghajari, Nushin

    2015-11-23

    GMP synthetase (GMPS), a key enzyme in the purine biosynthetic pathway performs catalysis through a coordinated process across two catalytic pockets for which the mechanism remains unclear. Crystal structures of Plasmodium falciparum GMPS in conjunction with mutational and enzyme kinetic studies reported here provide evidence that an 85° rotation of the GATase domain is required for ammonia channelling and thus for the catalytic activity of this two-domain enzyme. We suggest that conformational changes in helix 371-375 holding catalytic residues and in loop 376-401 along the rotation trajectory trigger the different steps of catalysis, and establish the central role of Glu374 in allostery and inter-domain crosstalk. These studies reveal the mechanism of domain rotation and inter-domain communication, providing a molecular framework for the function of all single polypeptide GMPSs and form a solid basis for rational drug design targeting this therapeutically important enzyme.

  12. Active site coupling in Plasmodium falciparum GMP synthetase is triggered by domain rotation

    PubMed Central

    Ballut, Lionel; Violot, Sébastien; Shivakumaraswamy, Santosh; Thota, Lakshmi Prasoona; Sathya, Manu; Kunala, Jyothirmai; Dijkstra, Bauke W.; Terreux, Raphaël; Haser, Richard; Balaram, Hemalatha; Aghajari, Nushin

    2015-01-01

    GMP synthetase (GMPS), a key enzyme in the purine biosynthetic pathway performs catalysis through a coordinated process across two catalytic pockets for which the mechanism remains unclear. Crystal structures of Plasmodium falciparum GMPS in conjunction with mutational and enzyme kinetic studies reported here provide evidence that an 85° rotation of the GATase domain is required for ammonia channelling and thus for the catalytic activity of this two-domain enzyme. We suggest that conformational changes in helix 371–375 holding catalytic residues and in loop 376–401 along the rotation trajectory trigger the different steps of catalysis, and establish the central role of Glu374 in allostery and inter-domain crosstalk. These studies reveal the mechanism of domain rotation and inter-domain communication, providing a molecular framework for the function of all single polypeptide GMPSs and form a solid basis for rational drug design targeting this therapeutically important enzyme. PMID:26592566

  13. Modulation of Vasomotive Activity in Rabbit External Ophthalmic Artery by Neuropeptides

    PubMed Central

    Delgado, Esmeralda Sofia Costa; Marques-Neves, Carlos; Rocha, Maria Isabel Sousa; Sales-Luís, José Paulo Pacheco; Silva-Carvalho, Luís Filipe

    2012-01-01

    Purpose. To investigate the vasomotive activity upon the external ophthalmic artery of vasointestinal peptide (VIP) and neuropeptide Y (NPY) using a previously developed model. Methods. Isolated rabbit eyes (n = 12) were perfused in situ with tyrode through the external ophthalmic artery. Effects of intra-arterial injections of NPY 200 μg/ml (Group A; n = 6) and VIP 200 μg/ml (Group B; n = 6) on the recorded pressure were obtained. For statistical analysis, Student's paired t-test and Fast Fourier Transform were used. Results. Spontaneous oscillations were observed before any drug administration in the 12 rabbit models. NPY produced an increase in total vascular resistance and a higher frequency and amplitude of oscillations, while VIP evoked the opposite effects. Conclusions. This study provides evidence of vasomotion in basal conditions in rabbit external ophthalmic artery. Concerning drug effects, NPY increased arterial resistance and enhanced vasomotion while VIP produced opposite effects which demonstrates their profound influence in arterial vasomotion. PMID:22496962

  14. Single- vs. double-bundle anterior cruciate ligament reconstruction: a new aspect of knee assessment during activities involving dynamic knee rotation.

    PubMed

    Czamara, Andrzej; Królikowska, Aleksandra; Szuba, Łukasz; Widuchowski, Wojciech; Kentel, Maciej

    2015-02-01

    Few studies have compared single-bundle (SB) and double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) in the knee joint during activities involving change-of-direction maneuvers and knee rotation. This study examined whether the type of ACLR contributes to postphysiotherapy outcomes, with an emphasis on knee function assessment during activities involving dynamic knee rotation. Fifteen male patients after SB ACLR and 15 male patients after DB ACLR took part in the same physiotherapy program. Twenty-four weeks after ACLR, both groups underwent anterior laxity measurement, pivot shift tests, range of movement and joint circumference measurements, subjective assessment of pain and stability levels in the knee joint, peak torque measurement of the muscles rotating the tibia toward the femur, and a run test with maximal speed and change-of-direction maneuvers. Comparative analysis did not show any differences between the results of anterior tibial translation, pivot shift test, range of movement and joint circumference, and subjective assessment of pain and knee joint stability levels. No differences were noted between the groups in peak torque values obtained from the muscles responsible for internal and external tibial rotation or results of the run test. The data obtained from this study can be used by research teams to monitor and compare the effectiveness of various study protocols involving surgical and physiotherapy treatment. The data are especially useful when combined with the clinical assessment of patients who would like to return to sport.

  15. Single- vs. double-bundle anterior cruciate ligament reconstruction: a new aspect of knee assessment during activities involving dynamic knee rotation.

    PubMed

    Czamara, Andrzej; Królikowska, Aleksandra; Szuba, Łukasz; Widuchowski, Wojciech; Kentel, Maciej

    2015-02-01

    Few studies have compared single-bundle (SB) and double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) in the knee joint during activities involving change-of-direction maneuvers and knee rotation. This study examined whether the type of ACLR contributes to postphysiotherapy outcomes, with an emphasis on knee function assessment during activities involving dynamic knee rotation. Fifteen male patients after SB ACLR and 15 male patients after DB ACLR took part in the same physiotherapy program. Twenty-four weeks after ACLR, both groups underwent anterior laxity measurement, pivot shift tests, range of movement and joint circumference measurements, subjective assessment of pain and stability levels in the knee joint, peak torque measurement of the muscles rotating the tibia toward the femur, and a run test with maximal speed and change-of-direction maneuvers. Comparative analysis did not show any differences between the results of anterior tibial translation, pivot shift test, range of movement and joint circumference, and subjective assessment of pain and knee joint stability levels. No differences were noted between the groups in peak torque values obtained from the muscles responsible for internal and external tibial rotation or results of the run test. The data obtained from this study can be used by research teams to monitor and compare the effectiveness of various study protocols involving surgical and physiotherapy treatment. The data are especially useful when combined with the clinical assessment of patients who would like to return to sport. PMID:25148470

  16. Association between rotation-related impairments and activity type in people with and without low back pain

    PubMed Central

    Weyrauch, Stephanie A.; Bohall, Sara C.; Sorensen, Christopher J.; Van Dillen, Linda R.

    2015-01-01

    Objective To determine if people with low back pain (LBP) who regularly participated in a rotation-related activity displayed more rotation-related impairments than people without LBP who did and did not participate in the activity. Design Secondary analysis of data from a case-control study. Setting Musculoskeletal analysis laboratory at an academic medical center. Participants A convenience sample of 55 participants with LBP who participated in a rotation-related sport, 26 back healthy controls who participated in a rotation-related sport (BHC+RRS) and 42 back healthy controls who did not participate in a rotation-related sport (BHC-RRS). Participants were matched based on age, gender, and activity level. Interventions Not applicable. Main Outcome Measures The total number of rotation-related impairments and asymmetric rotation-related impairments identified during a standardized clinical examination. Results Compared to the BHC-RRS group, both the LBP and BHC+RRS groups displayed significantly more (1) rotation-related impairments (LBP: p<.001; BHC+RRS: p=.015) (2) asymmetric rotation-related impairments (LBP: p=.006; BHC+RRS: p=.020) and (3) rotation-related impairments with trunk movement tests (LBP: p=.002; BHC+RRS: p<.001). The LBP group had significantly more rotation-related impairments with extremity movement tests than both of the back healthy groups (BHC+RRS: p=.011; BHC-RRS: p<.001). Conclusions LBP and BHC+RRS groups demonstrated a similar number of total rotation-related impairments and asymmetric rotation-related impairments, and these numbers were greater than those of the BHC-RRS group. Compared to people without LBP, people with LBP displayed more rotation-related impairments when moving an extremity. These findings suggest that impairments associated with extremity movements may be associated with having a LBP condition. PMID:25933914

  17. A Computational Model of Dynein Activation Patterns that Can Explain Nodal Cilia Rotation

    PubMed Central

    Chen, Duanduan; Zhong, Yi

    2015-01-01

    Normal left-right patterning in vertebrates depends on the rotational movement of nodal cilia. In order to produce this ciliary motion, the activity of axonemal dyneins must be tightly regulated in a temporal and spatial manner; the specific activation pattern of the dynein motors in the nodal cilia has not been reported. Contemporary imaging techniques cannot directly assess dynein activity in a living cilium. In this study, we establish a three-dimensional model to mimic the ciliary ultrastructure and assume that the activation of dynein proteins is related to the interdoublet distance. By employing finite-element analysis and grid deformation techniques, we simulate the mechanical function of dyneins by pairs of point loads, investigate the time-variant interdoublet distance, and simulate the dynein-triggered ciliary motion. The computational results indicate that, to produce the rotational movement of nodal cilia, the dynein activity is transferred clockwise (looking from the tip) between the nine doublet microtubules, and along each microtubule, the dynein activation should occur faster at the basal region and slower when it is close to the ciliary tip. Moreover, the time cost by all the dyneins along one microtubule to be activated can be used to deduce the dynein activation pattern; it implies that, as an alternative method, measuring this time can indirectly reveal the dynein activity. The proposed protein-structure model can simulate the ciliary motion triggered by various dynein activation patterns explicitly and may contribute to furthering the studies on axonemal dynein activity. PMID:26153700

  18. A computational model of dynein activation patterns that can explain nodal cilia rotation.

    PubMed

    Chen, Duanduan; Zhong, Yi

    2015-07-01

    Normal left-right patterning in vertebrates depends on the rotational movement of nodal cilia. In order to produce this ciliary motion, the activity of axonemal dyneins must be tightly regulated in a temporal and spatial manner; the specific activation pattern of the dynein motors in the nodal cilia has not been reported. Contemporary imaging techniques cannot directly assess dynein activity in a living cilium. In this study, we establish a three-dimensional model to mimic the ciliary ultrastructure and assume that the activation of dynein proteins is related to the interdoublet distance. By employing finite-element analysis and grid deformation techniques, we simulate the mechanical function of dyneins by pairs of point loads, investigate the time-variant interdoublet distance, and simulate the dynein-triggered ciliary motion. The computational results indicate that, to produce the rotational movement of nodal cilia, the dynein activity is transferred clockwise (looking from the tip) between the nine doublet microtubules, and along each microtubule, the dynein activation should occur faster at the basal region and slower when it is close to the ciliary tip. Moreover, the time cost by all the dyneins along one microtubule to be activated can be used to deduce the dynein activation pattern; it implies that, as an alternative method, measuring this time can indirectly reveal the dynein activity. The proposed protein-structure model can simulate the ciliary motion triggered by various dynein activation patterns explicitly and may contribute to furthering the studies on axonemal dynein activity.

  19. Physical activity recognition based on rotated acceleration data using quaternion in sedentary behavior: a preliminary study.

    PubMed

    Shin, Y E; Choi, W H; Shin, T M

    2014-01-01

    This paper suggests a physical activity assessment method based on quaternion. To reduce user inconvenience, we measured the activity using a mobile device which is not put on fixed position. Recognized results were verified with various machine learning algorithms, such as neural network (multilayer perceptron), decision tree (J48), SVM (support vector machine) and naive bayes classifier. All algorithms have shown over 97% accuracy including decision tree (J48), which recognized the activity with 98.35% accuracy. As a result, physical activity assessment method based on rotated acceleration using quaternion can classify sedentary behavior with more accuracy without considering devices' position and orientation. PMID:25571109

  20. Minimalist coupled evolution model for stellar X-ray activity, rotation, mass loss, and magnetic field

    NASA Astrophysics Data System (ADS)

    Blackman, Eric G.; Owen, James E.

    2016-05-01

    Late-type main-sequence stars exhibit an X-ray to bolometric flux ratio that depends on {tilde{R}o}, the ratio of rotation period to convective turnover time, as {tilde{R}o}^{-ζ } with 2 ≤ ζ ≤ 3 for {tilde{R}o} > 0.13, but saturates with |ζ| < 0.2 for {tilde{R}o} < 0.13. Saturated stars are younger than unsaturated stars and show a broader spread of rotation rates and X-ray activity. The unsaturated stars have magnetic fields and rotation speeds that scale roughly with the square root of their age, though possibly flattening for stars older than the Sun. The connection between faster rotators, stronger fields, and higher activity has been established observationally, but a theory for the unified time-evolution of X-ray luminosity, rotation, magnetic field and mass loss that captures the above trends has been lacking. Here we derive a minimalist holistic framework for the time evolution of these quantities built from combining a Parker wind with new ingredients: (1) explicit sourcing of both the thermal energy launching the wind and the X-ray luminosity via dynamo produced magnetic fields; (2) explicit coupling of X-ray activity and mass-loss saturation to dynamo saturation (via magnetic helicity build-up and convection eddy shredding); (3) use of coronal equilibrium to determine how magnetic energy is divided into wind and X-ray contributions. For solar-type stars younger than the Sun, we infer conduction to be a subdominant power loss compared to X-rays and wind. For older stars, conduction is more important, possibly quenching the wind and reducing angular momentum loss. We focus on the time evolution for stars younger than the Sun, highlighting what is possible for further generalizations. Overall, the approach shows promise towards a unified explanation of all of the aforementioned observational trends.

  1. A common model for cytokine receptor activation: combined scissor-like rotation and self-rotation of receptor dimer induced by class I cytokine.

    PubMed

    Pang, Xiaodong; Zhou, Huan-Xiang

    2012-01-01

    The precise mechanism by which the binding of a class I cytokine to the extracellular domain of its corresponding receptor transmits a signal through the cell membrane remains unclear. Receptor activation involves a cytokine-receptor complex with a 1∶2 stoichiometry. Previously we used our transient-complex theory to calculate the rate constant of the initial cytokine-receptor binding to form a 1∶1 complex. Here we computed the binding pathway leading to the 1∶2 activation complex. Three cytokine systems (growth hormone, erythropoietin, and prolactin) were studied, and the focus was on the binding of the extracellular domain of the second receptor molecule after forming the 1∶1 complex. According to the transient-complex theory, translational and rotation diffusion of the binding entities bring them together to form a transient complex, which has near-native relative separation and orientation but not the short-range specific native interactions. Subsequently conformational rearrangement leads to the formation of the native complex. We found that the changes in relative orientations between the two receptor molecules from the transient complex to the 1∶2 native complex are similar for the three cytokine-receptor systems. We thus propose a common model for receptor activation by class I cytokines, involving combined scissor-like rotation and self-rotation of the two receptor molecules. Both types of rotations seem essential: the scissor-like rotation separates the intracellular domains of the two receptor molecules to make room for the associated Janus kinase molecules, while the self-rotation allows them to orient properly for transphosphorylation. This activation model explains a host of experimental observations. The transient-complex based approach presented here may provide a strategy for designing antagonists and prove useful for elucidating activation mechanisms of other receptors.

  2. Sunspot Rotation as a Driver of Major Solar Eruptions in the NOAA Active Region 12158

    NASA Astrophysics Data System (ADS)

    Vemareddy, P.; Cheng, X.; Ravindra, B.

    2016-09-01

    We studied the development conditions of sigmoid structure under the influence of the magnetic non-potential characteristics of a rotating sunspot in the active region (AR) 12158. Vector magnetic field measurements from the Helioseismic Magnetic Imager and coronal EUV observations from the Atmospheric Imaging Assembly reveal that the erupting inverse-S sigmoid had roots at the location of the rotating sunspot. The sunspot rotates at a rate of 0°-5° h-1 with increasing trend in the first half followed by a decrease. The time evolution of many non-potential parameters had a good correspondence with the sunspot rotation. The evolution of the AR magnetic structure is approximated by a time series of force-free equilibria. The non-linear force-free field magnetic structure around the sunspot manifests the observed sigmoid structure. Field lines from the sunspot periphery constitute the body of the sigmoid and those from the interior overlie the sigmoid, similar to a flux rope structure. While the sunspot was rotating, two major coronal mass ejection eruptions occurred in the AR. During the first (second) event, the coronal current concentrations were enhanced (degraded), consistent with the photospheric net vertical current; however, magnetic energy was released during both cases. The analysis results suggest that the magnetic connections of the sigmoid are driven by the slow motion of sunspot rotation, which transforms to a highly twisted flux rope structure in a dynamical scenario. Exceeding the critical twist in the flux rope probably leads to the loss of equilibrium, thus triggering the onset of the two eruptions.

  3. Dynamic Three-Dimensional Shoulder Mri during Active Motion for Investigation of Rotator Cuff Diseases

    PubMed Central

    Tempelaere, Christine; Pierrart, Jérome; Lefèvre-Colau, Marie-Martine; Vuillemin, Valérie; Cuénod, Charles-André; Hansen, Ulrich; Mir, Olivier; Skalli, Wafa; Gregory, Thomas

    2016-01-01

    Background MRI is the standard methodology in diagnosis of rotator cuff diseases. However, many patients continue to have pain despite treatment, and MRI of a static unloaded shoulder seems insufficient for best diagnosis and treatment. This study evaluated if Dynamic MRI provides novel kinematic data that can be used to improve the understanding, diagnosis and best treatment of rotator cuff diseases. Methods Dynamic MRI provided real-time 3D image series and was used to measure changes in the width of subacromial space, superior-inferior translation and anterior-posterior translation of the humeral head relative to the glenoid during active abduction. These measures were investigated for consistency with the rotator cuff diseases classifications from standard MRI. Results The study included: 4 shoulders with massive rotator cuff tears, 5 shoulders with an isolated full-thickness supraspinatus tear, 5 shoulders with tendinopathy and 6 normal shoulders. A change in the width of subacromial space greater than 4mm differentiated between rotator cuff diseases with tendon tears (massive cuff tears and supraspinatus tear) and without tears (tendinopathy) (p = 0.012). The range of the superior-inferior translation was higher in the massive cuff tears group (6.4mm) than in normals (3.4mm) (p = 0.02). The range of the anterior-posterior translation was higher in the massive cuff tears (9.2 mm) and supraspinatus tear (9.3 mm) shoulders compared to normals (3.5mm) and tendinopathy (4.8mm) shoulders (p = 0.05). Conclusion The Dynamic MRI enabled a novel measure; ‘Looseness’, i.e. the translation of the humeral head on the glenoid during an abduction cycle. Looseness was better able at differentiating different forms of rotator cuff disease than a simple static measure of relative glenohumeral position. PMID:27434235

  4. Subunit rotation models activation of serotonin 5-HT3AB receptors by agonists.

    PubMed

    Maksay, Gábor; Simonyi, Miklós; Bikádi, Zsolt

    2004-10-01

    The N-terminal extracellular regions of heterooligomeric 3AB-type human 5-hydroxytryptamine receptors (5-HT3ABR) were modelled based on the crystal structure of snail acetylcholine binding protein AChBP. Stepwise rotation of subunit A by 5 degrees was performed between -10 degrees and 15 degrees to mimic agonist binding and receptor activation. Anticlockwise rotation reduced the size of the binding cavity in interface AB and reorganised the network of hydrogen bonds along the interface. AB subunit dimers with different rotations were applied for docking of ligands with different efficacies: 5-HT, m-chlorophenylbiguanide, SR 57227, quinolinyl piperazine and lerisetron derivatives. All ligands were docked into the dimer with -10 degrees rotation representing ligand-free, open binding cavities similarly, without pharmacological discrimination. Their ammonium ions were in hydrogen bonding distance to the backbone carbonyl of W183. Anticlockwise rotation and contraction of the binding cavity led to distinctive docking interactions of agonists with E129 and cation-pi interactions of their ammonium ions. Side chains of several further amino acids participating in docking (Y143, Y153, Y234 and E236) are in agreement with the effects of point mutations in the binding loops. Our model postulates that 5-HT binds to W183 in a hydrophobic cleft as well as to E236 in a hydrophilic vestibule. Then it elicits anticlockwise rotation to draw in loop C via pi-cation-pi interactions of its ammonium ion with W183 and Y234. Finally, closure of the binding cavity might end in rebinding of 5-HT to E129 in the hydrophilic vestibule.

  5. Influence of External Nitrogen on Nitrogenase Enzyme Activity and Auxin Production in Herbaspirillum seropedicae (Z78)

    PubMed Central

    Yin, Tan Tzy; Pin, Ui Li; Ghazali, Amir Hamzah Ahmad

    2015-01-01

    The production of nitrogenase enzyme and auxins by free living diazotrophs has the potential to influence the growth of host plants. In this study, diazotrophs were grown in the presence of various concentrations of nitogen (N) to determine the optimal concentration of N for microbial growth stimulation, promotion of gaseous N (N2) fixation, and phytohormone production. Therefore, we investigate whether different levels of N supplied to Herbaspirillum seropedicae (Z78) have significant effects on nitrogenase activity and auxin production. The highest nitrogenase activity and the lowest auxin production of H. seropedicae (Z78) were both recorded at 0 gL−1 of NH4Cl. Higher levels of external N caused a significant decrease in the nitrogenase activity and an increased production of auxins. In a subsequent test, two different inoculum sizes of Z78 (106 and 1012 cfu/ml) were used to study the effect of different percentages of acetylene on nitrogenase activity of the inoculum via the acetylene reduction assay (ARA). The results showed that the optimal amount of acetylene required for nitrogenase enzyme activity was 5% for the 106 cfu/ml inoculum, whereas the higher inoculum size (1012 cfu/ml) required at least 10% of acetylene for optimal nitrogenase activity. These findings provide a clearer understanding of the effects of N levels on diazotrophic nitrogenase activity and auxin production, which are important factors influencing plant growth. PMID:26868594

  6. Phosphatidylserine externalization and procoagulant activation of erythrocytes induced by Pseudomonas aeruginosa virulence factor pyocyanin.

    PubMed

    Qadri, Syed M; Donkor, David A; Bhakta, Varsha; Eltringham-Smith, Louise J; Dwivedi, Dhruva J; Moore, Jane C; Pepler, Laura; Ivetic, Nikola; Nazi, Ishac; Fox-Robichaud, Alison E; Liaw, Patricia C; Sheffield, William P

    2016-04-01

    The opportunistic pathogen Pseudomonas aeruginosa causes a wide range of infections in multiple hosts by releasing an arsenal of virulence factors such as pyocyanin. Despite numerous reports on the pleiotropic cellular targets of pyocyanin toxicity in vivo, its impact on erythrocytes remains elusive. Erythrocytes undergo an apoptosis-like cell death called eryptosis which is characterized by cell shrinkage and phosphatidylserine (PS) externalization; this process confers a procoagulant phenotype on erythrocytes as well as fosters their phagocytosis and subsequent clearance from the circulation. Herein, we demonstrate that P. aeruginosa pyocyanin-elicited PS exposure and cell shrinkage in erythrocyte while preserving the membrane integrity. Mechanistically, exposure of erythrocytes to pyocyanin showed increased cytosolic Ca(2+) activity as well as Ca(2+) -dependent proteolytic processing of μ-calpain. Pyocyanin further up-regulated erythrocyte ceramide abundance and triggered the production of reactive oxygen species. Pyocyanin-induced increased PS externalization in erythrocytes translated into enhanced prothrombin activation and fibrin generation in plasma. As judged by carboxyfluorescein succinimidyl-ester labelling, pyocyanin-treated erythrocytes were cleared faster from the murine circulation as compared to untreated erythrocytes. Furthermore, erythrocytes incubated in plasma from patients with P. aeruginosa sepsis showed increased PS exposure as compared to erythrocytes incubated in plasma from healthy donors. In conclusion, the present study discloses the eryptosis-inducing effect of the virulence factor pyocyanin, thereby shedding light on a potentially important mechanism in the systemic complications of P. aeruginosa infection. PMID:26781477

  7. No tillage combined with crop rotation improves soil microbial community composition and metabolic activity.

    PubMed

    Sun, Bingjie; Jia, Shuxia; Zhang, Shixiu; McLaughlin, Neil B; Liang, Aizhen; Chen, Xuewen; Liu, Siyi; Zhang, Xiaoping

    2016-04-01

    Soil microbial community can vary with different agricultural managements, which in turn can affect soil quality. The objective of this work was to evaluate the effects of long-term tillage practice (no tillage (NT) and conventional tillage (CT)) and crop rotation (maize-soybean (MS) rotation and monoculture maize (MM)) on soil microbial community composition and metabolic capacity in different soil layers. Long-term NT increased the soil organic carbon (SOC) and total nitrogen (TN) mainly at the 0-5 cm depth which was accompanied with a greater microbial abundance. The greater fungi-to-bacteria (F/B) ratio was found in NTMS at the 0-5 cm depth. Both tillage and crop rotation had a significant effect on the metabolic activity, with the greatest average well color development (AWCD) value in NTMS soil at all three soil depths. Redundancy analysis (RDA) showed that the shift in microbial community composition was accompanied with the changes in capacity of utilizing different carbon substrates. Therefore, no tillage combined with crop rotation could improve soil biological quality and make agricultural systems more sustainable.

  8. No tillage combined with crop rotation improves soil microbial community composition and metabolic activity.

    PubMed

    Sun, Bingjie; Jia, Shuxia; Zhang, Shixiu; McLaughlin, Neil B; Liang, Aizhen; Chen, Xuewen; Liu, Siyi; Zhang, Xiaoping

    2016-04-01

    Soil microbial community can vary with different agricultural managements, which in turn can affect soil quality. The objective of this work was to evaluate the effects of long-term tillage practice (no tillage (NT) and conventional tillage (CT)) and crop rotation (maize-soybean (MS) rotation and monoculture maize (MM)) on soil microbial community composition and metabolic capacity in different soil layers. Long-term NT increased the soil organic carbon (SOC) and total nitrogen (TN) mainly at the 0-5 cm depth which was accompanied with a greater microbial abundance. The greater fungi-to-bacteria (F/B) ratio was found in NTMS at the 0-5 cm depth. Both tillage and crop rotation had a significant effect on the metabolic activity, with the greatest average well color development (AWCD) value in NTMS soil at all three soil depths. Redundancy analysis (RDA) showed that the shift in microbial community composition was accompanied with the changes in capacity of utilizing different carbon substrates. Therefore, no tillage combined with crop rotation could improve soil biological quality and make agricultural systems more sustainable. PMID:26631020

  9. Computation of instantaneous and time-averaged active acoustic intensity field around rotating source

    NASA Astrophysics Data System (ADS)

    Mao, Yijun; Xu, Chen; Qi, Datong

    2015-02-01

    A vector aeroacoustics method is developed to analyze the acoustic energy flow path from the rotating source. In this method, the instantaneous and time-averaged active acoustic intensity vectors are evaluated from the time-domain and frequency-domain acoustic pressure and acoustic velocity formulations, respectively. With the above method, the acoustic intensity vectors and the acoustic energy streamlines are visualized to investigate the propagation feature of the noise radiated from the monopole and dipole point sources and the rotor in subsonic rotation. The result reveals that a portion of the acoustic energy spirals many circles before moving towards the far field, and another portion of the acoustic energy firstly flows inward along the radial direction and then propagates along the axial direction. Further, an acoustic black hole exists in the plane of source rotation, from which the acoustic energy cannot escape once the acoustic energy flows into it. Moreover, by visualizing the acoustic intensity field around the rotating sources, the acoustic-absorption performance of the acoustic liner built in the casing and centerbody is discussed.

  10. External protons destabilize the activated voltage sensor in hERG channels.

    PubMed

    Shi, Yu Patrick; Cheng, Yen May; Van Slyke, Aaron C; Claydon, Tom W

    2014-03-01

    Extracellular acidosis shifts hERG channel activation to more depolarized potentials and accelerates channel deactivation; however, the mechanisms underlying these effects are unclear. External divalent cations, e.g., Ca(2+) and Cd(2+), mimic these effects and coordinate within a metal ion binding pocket composed of three acidic residues in hERG: D456 and D460 in S2 and D509 in S3. A common mechanism may underlie divalent cation and proton effects on hERG gating. Using two-electrode voltage clamp, we show proton sensitivity of hERG channel activation (pKa = 5.6), but not deactivation, was greatly reduced in the presence of Cd(2+) (0.1 mM), suggesting a common binding site for the Cd(2+) and proton effect on activation and separable effects of protons on activation and deactivation. Mutational analysis confirmed that D509 plays a critical role in the pH dependence of activation, as shown previously, and that cooperative actions involving D456 and D460 are also required. Importantly, neutralization of all three acidic residues abolished the proton-induced shift of activation, suggesting that the metal ion binding pocket alone accounts for the effects of protons on hERG channel activation. Voltage-clamp fluorimetry measurements demonstrated that protons shifted the voltage dependence of S4 movement to more depolarized potentials. The data indicate a site and mechanism of action for protons on hERG activation gating; protonation of D456, D460 and D509 disrupts interactions between these residues and S4 gating charges to destabilize the activated configuration of S4.

  11. Superdiffusion in dispersions of active colloids driven by an external field and their sedimentation equilibrium

    NASA Astrophysics Data System (ADS)

    Chen, Yen-Fu; Wei, Hsien-Hung; Sheng, Yu-Jane; Tsao, Heng-Kwong

    2016-04-01

    The diffusive behaviors of active colloids with run-and-tumble movement are explored by dissipative particle dynamics simulations for self-propelled particles (force dipole) and external field-driven particles (point force). The self-diffusion of tracers (solvent) is investigated as well. The influences of the active force, run time, and concentration associated with active particles are studied. For the system of self-propelled particles, the normal diffusion is observed for both active particles and tracers. The diffusivity of the former is significantly greater than that of the latter. For the system of field-driven particles, the superdiffusion is seen for both active particles and tracers. In contrast, it is found that the anomalous diffusion exponent of the former is slightly less than that of the latter. The anomalous diffusion is caused by the many-body, long-range hydrodynamic interactions. In spite of the superdiffusion, the sedimentation equilibrium of field-driven particles can be acquired and the density profile is still exponentially decayed. The sedimentation length of field-driven particles is always greater than that of self-propelled particles.

  12. Superdiffusion in dispersions of active colloids driven by an external field and their sedimentation equilibrium.

    PubMed

    Chen, Yen-Fu; Wei, Hsien-Hung; Sheng, Yu-Jane; Tsao, Heng-Kwong

    2016-04-01

    The diffusive behaviors of active colloids with run-and-tumble movement are explored by dissipative particle dynamics simulations for self-propelled particles (force dipole) and external field-driven particles (point force). The self-diffusion of tracers (solvent) is investigated as well. The influences of the active force, run time, and concentration associated with active particles are studied. For the system of self-propelled particles, the normal diffusion is observed for both active particles and tracers. The diffusivity of the former is significantly greater than that of the latter. For the system of field-driven particles, the superdiffusion is seen for both active particles and tracers. In contrast, it is found that the anomalous diffusion exponent of the former is slightly less than that of the latter. The anomalous diffusion is caused by the many-body, long-range hydrodynamic interactions. In spite of the superdiffusion, the sedimentation equilibrium of field-driven particles can be acquired and the density profile is still exponentially decayed. The sedimentation length of field-driven particles is always greater than that of self-propelled particles. PMID:27176356

  13. Effects of cycle duration of an external electrostatic field on anammox biomass activity.

    PubMed

    Yin, Xin; Qiao, Sen; Zhou, Jiti

    2016-01-01

    In this study, the effects of different cycle durations of an external electrostatic field on an anammox biomass were investigated. The total application time per day was 12 h at 2 V/cm for different cycle durations (i.e., continuous application-resting time) of 3 h-3 h, 6 h-6 h, and 12 h-12 h. Compared with the control reactor, the nitrogen removal rates (NRRs) increased by 18.7%, 27.4% and 8.50% using an external electrostatic field application with a continuous application time of 3 h, 6 h and 12 h. Moreover, after the reactor was running smoothly for approximately 215 days under the optimal electrostatic field condition (mode 2, continuous application-rest time: 6 h-6 h), the total nitrogen (TN) removal rate reached a peak value of approximately 6468 g-N/m(3)/d, which was 44.7% higher than the control. The increase in 16S rRNA gene copy numbers, heme c content and enzyme activities were demonstrated to be the main reasons for enhancement of the NRR of the anammox process. Additionally, transmission electron microscope observations proved that a morphological change in the anammox biomass occurred under an electrostatic field application. PMID:26794647

  14. Effects of cycle duration of an external electrostatic field on anammox biomass activity

    NASA Astrophysics Data System (ADS)

    Yin, Xin; Qiao, Sen; Zhou, Jiti

    2016-01-01

    In this study, the effects of different cycle durations of an external electrostatic field on an anammox biomass were investigated. The total application time per day was 12 h at 2 V/cm for different cycle durations (i.e., continuous application-resting time) of 3 h-3 h, 6 h-6 h, and 12 h-12 h. Compared with the control reactor, the nitrogen removal rates (NRRs) increased by 18.7%, 27.4% and 8.50% using an external electrostatic field application with a continuous application time of 3 h, 6 h and 12 h. Moreover, after the reactor was running smoothly for approximately 215 days under the optimal electrostatic field condition (mode 2, continuous application-rest time: 6 h-6 h), the total nitrogen (TN) removal rate reached a peak value of approximately 6468 g-N/m3/d, which was 44.7% higher than the control. The increase in 16S rRNA gene copy numbers, heme c content and enzyme activities were demonstrated to be the main reasons for enhancement of the NRR of the anammox process. Additionally, transmission electron microscope observations proved that a morphological change in the anammox biomass occurred under an electrostatic field application.

  15. Effects of cycle duration of an external electrostatic field on anammox biomass activity

    PubMed Central

    Yin, Xin; Qiao, Sen; Zhou, Jiti

    2016-01-01

    In this study, the effects of different cycle durations of an external electrostatic field on an anammox biomass were investigated. The total application time per day was 12 h at 2 V/cm for different cycle durations (i.e., continuous application-resting time) of 3 h-3 h, 6 h-6 h, and 12 h-12 h. Compared with the control reactor, the nitrogen removal rates (NRRs) increased by 18.7%, 27.4% and 8.50% using an external electrostatic field application with a continuous application time of 3 h, 6 h and 12 h. Moreover, after the reactor was running smoothly for approximately 215 days under the optimal electrostatic field condition (mode 2, continuous application-rest time: 6 h-6 h), the total nitrogen (TN) removal rate reached a peak value of approximately 6468 g-N/m3/d, which was 44.7% higher than the control. The increase in 16S rRNA gene copy numbers, heme c content and enzyme activities were demonstrated to be the main reasons for enhancement of the NRR of the anammox process. Additionally, transmission electron microscope observations proved that a morphological change in the anammox biomass occurred under an electrostatic field application. PMID:26794647

  16. Analysis of the Rotationally-Resolved Spectra of the Vibronically-Active Molecules

    NASA Astrophysics Data System (ADS)

    Melnik, Dmitry G.; Miller, Terry A.

    2013-06-01

    Rotational structure of the vibronically coupled, and specifically, Jahn-Teller active molecules in isolated vibronic states has been studied for the decades, and the corresponding Hamiltonian and relationship of its parameters to the molecular properties are well-established, at least for the e vibronic states. However, in many cases an isolated state approach, both for the ground and vibronically excited levels, does not produce satisfactory results either because the experimentally obtained parameters of such model are not physically transparent, or the model fails to predict the observed spectrum to the experimental accuracy. To circumvent these problems, we develop, from the molecular symmetry standpoint, an effective coupled state rotational Hamiltonian directly accounting for the interactions within the appropriate subset of the interacting vibronic states. This approach is expected to be useful for the analysis of the rotational level structure of the closely-spaced vibronic levels such as those occurring in the vibrationally excited manifolds of the open-shell molecules. The application of this approach to the spectra of the nitrate radical, NO_3, in the Jahn-Teller active ˜{A}^2E'' state, will be discussed. D. G. Melnik, T. A. Miller and J. Liu, TI15, 67^th Molecular Spectroscopy Symposium, Columbus, 2012 M. Roudjane, T. J. Codd and T. A. Miller, TI03, 67^th Molecular Spectroscopy Symposium, Columbus, 2012

  17. The rotation of sunspots in the solar active region NOAA 10930

    NASA Astrophysics Data System (ADS)

    Gopasyuk, O. S.

    2014-06-01

    The rotation of sunspots in the solar active region NOAA 10930 was investigated on the basis of the data on the longitudinal magnetic field and the Doppler velocities using magnetograms and dopplergrams taken with the Solar Optical Telescope installed aboard the HINODE mission. Under the assumption of axial symmetry, areally-mean vertical, radial, and azimuthal components of the magnetic field and velocity vectors were calculated in both sunspots. The plasma in the sunspots rotated in opposite directions: in the leading sunspot, clockwise, and in the following sunspot, counterclockwise. The magnetic flux tubes that formed sunspots of the active region on the solar surface were twisted in one direction, clockwise. Electric currents generated as a result of the rotation and twisting of magnetic flux tubes were also flowing in one direction. Azimuthal components of magnetic and velocity fields of both sunspot umbrae reached their maximum on December 11, 2006. By the start of the X3.4 flare (December 13, 2006), their values became practically equal to zero.

  18. Gamma-Ray Spectrometers Using Superconducting Transition Edge Sensors with External Active Feedback Bias

    SciTech Connect

    Chow, D.T.; van den Berg, M.L.; Loshak, A.; Frank, M.; Barbee, T.W.; Labov, S.E.

    2000-09-22

    The authors are developing x-ray and gamma-ray spectrometers with high absorption efficiency and high energy-resolution for x-ray and gamma-ray spectroscopy. They are microcalorimeters consisting of a bulk Sn absorber coupled to a Mo/Cu multilayer superconducting transition edge sensor (TES). The authors have measured an energy resolution of 70 eV FWHM for 60 keV incident gamma-rays using electrothermal feedback. They have also operated these microcalorimeters with an external active feedback bias to linearize the detector response, improve the count rate performance, and extend the detection energy range. They present x-ray and gamma-ray results operation of this detector design in both bias modes.

  19. Active mode locking of quantum cascade lasers in an external ring cavity.

    PubMed

    Revin, D G; Hemingway, M; Wang, Y; Cockburn, J W; Belyanin, A

    2016-05-05

    Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode-locked operation remains a challenge, despite dedicated effort. Here we report the demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents.

  20. Active mode locking of quantum cascade lasers in an external ring cavity

    PubMed Central

    Revin, D. G.; Hemingway, M.; Wang, Y.; Cockburn, J. W.; Belyanin, A.

    2016-01-01

    Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode-locked operation remains a challenge, despite dedicated effort. Here we report the demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents. PMID:27147409

  1. Active mode locking of quantum cascade lasers in an external ring cavity

    NASA Astrophysics Data System (ADS)

    Revin, D. G.; Hemingway, M.; Wang, Y.; Cockburn, J. W.; Belyanin, A.

    2016-05-01

    Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode-locked operation remains a challenge, despite dedicated effort. Here we report the demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents.

  2. Timing Behavior of the Magnetically Active Rotation-Powered Pulsar in the Supernova Remnant Kesteven 75

    NASA Technical Reports Server (NTRS)

    Livingstone, Margaret A.; Gavriil, Fotis P.; Kaspi, Victoria M.

    2009-01-01

    We report a large spin-up glitch in PSR J1846-0258 which coincided with the onset of magnetar-like behavior on 2006 May 31. We show that the pulsar experienced an unusually large glitch recovery, with a recovery fraction of Q = 5.9+/-0.3, resulting in a net decrease of the pulse frequency. Such a glitch recovery has never before been observed in a rotation-powered pulsar, however, similar but smaller glitch over-recovery has been recently reported in the magnetar AXP 4U 0142+61 and may have occurred in the SGR 1900+14. We discuss the implications of the unusual timing behavior in PSR J1846-0258 on its status as the first identified magnetically active rotation-powered pulsar.

  3. The factory and the beehive. II. Activity and rotation in Praesepe and the Hyades

    SciTech Connect

    Douglas, S. T.; Agüeros, M. A.; Bowsher, E. C.; Lemonias, J. J.; Fierroz, D. F.; Covey, K. R.; Bochanski, J. J.; Cargile, P. A.; Kraus, A.; Law, N. M.; Arce, H. G.; Kundert, A.

    2014-11-10

    Open clusters are collections of stars with a single, well-determined age, and can be used to investigate the connections between angular-momentum evolution and magnetic activity over a star's lifetime. We present the results of a comparative study of the relationship between stellar rotation and activity in two benchmark open clusters: Praesepe and the Hyades. As they have the same age and roughly solar metallicity, these clusters serve as an ideal laboratory for testing the agreement between theoretical and empirical rotation-activity relations at ≈600 Myr. We have compiled a sample of 720 spectra—more than half of which are new observations—for 516 high-confidence members of Praesepe; we have also obtained 139 new spectra for 130 high-confidence Hyads. We have also collected rotation periods (P {sub rot}) for 135 Praesepe members and 87 Hyads. To compare Hα emission, an indicator of chromospheric activity, as a function of color, mass, and Rossby number R{sub o} , we first calculate an expanded set of χ values, with which we can obtain the Hα to bolometric luminosity ratio, L {sub Hα}/L {sub bol}, even when spectra are not flux-calibrated and/or stars lack reliable distances. Our χ values cover a broader range of stellar masses and colors (roughly equivalent to spectral types from K0 to M9), and exhibit better agreement between independent calculations, than existing values. Unlike previous authors, we find no difference between the two clusters in their Hα equivalent width or L {sub Hα}/L {sub bol} distributions, and therefore take the merged Hα and P {sub rot} data to be representative of 600 Myr old stars. Our analysis shows that Hα activity in these stars is saturated for R{sub o}≤0.11{sub −0.03}{sup +0.02}. Above that value activity declines as a power-law with slope β=−0.73{sub −0.12}{sup +0.16}, before dropping off rapidly at R{sub o} ≈ 0.4. These data provide a useful anchor for calibrating the age-activity-rotation relation

  4. The Study of External Dose Rate and Retained Body Activity of Patients Receiving 131I Therapy for Differentiated Thyroid Carcinoma

    PubMed Central

    Zhang, Haiying; Jiao, Ling; Cui, Songye; Wang, Liang; Tan, Jian; Zhang, Guizhi; He, Yajing; Ruan, Shuzhou; Fan, Saijun; Zhang, Wenyi

    2014-01-01

    Radiation safety is an integral part of targeted radionuclide therapy. The aim of this work was to study the external dose rate and retained body activity as functions of time in differentiated thyroid carcinoma patients receiving 131I therapy. Seventy patients were stratified into two groups: the ablation group (A) and the follow-up group (FU). The patients’ external dose rate was measured, and simultaneously, their retained body radiation activity was monitored at various time points. The equations of the external dose rate and the retained body activity, described as a function of hours post administration, were fitted. Additionally, the release time for patients was calculated. The reduction in activity in the group receiving a second or subsequent treatment was more rapid than the group receiving only the initial treatment. Most important, an expeditious method was established to indirectly evaluate the retained body activity of patients by measuring the external dose rate with a portable radiation survey meter. By this method, the calculated external dose rate limits are 19.2, 8.85, 5.08 and 2.32 μSv·h−1 at 1, 1.5, 2 and 3 m, respectively, according to a patient’s released threshold level of retained body activity <400 MBq. This study is beneficial for radiation safety decision-making. PMID:25337944

  5. Iterative weighted average diffusion as a novel external force in the active contour model

    NASA Astrophysics Data System (ADS)

    Mirov, Ilya S.; Nakhmani, Arie

    2016-03-01

    The active contour model has good performance in boundary extraction for medical images; particularly, Gradient Vector Flow (GVF) active contour model shows good performance at concavity convergence and insensitivity to initialization, yet it is susceptible to edge leaking, deep and narrow concavities, and has some issues handling noisy images. This paper proposes a novel external force, called Iterative Weighted Average Diffusion (IWAD), which used in tandem with parametric active contours, provides superior performance in images with high values of concavity. The image gradient is first turned into an edge image, smoothed, and modified with enhanced corner detection, then the IWAD algorithm diffuses the force at a given pixel based on its 3x3 pixel neighborhood. A forgetting factor, φ, is employed to ensure that forces being spread away from the boundary of the image will attenuate. The experimental results show better behavior in high curvature regions, faster convergence, and less edge leaking than GVF when both are compared to expert manual segmentation of the images.

  6. Solar-like oscillations and magnetic activity of the slow rotator EK Eridani

    NASA Astrophysics Data System (ADS)

    Dall, T. H.; Bruntt, H.; Stello, D.; Strassmeier, K. G.

    2010-05-01

    Aims: We aim to understand the interplay between non-radial oscillations and stellar magnetic activity and test the feasibility of doing asteroseismology of magnetically active stars. We investigate the active slow rotator EK Eri which is the likely descendant of an Ap star. Methods: We analyze 30 years of photometric time-series data, 3 years of HARPS radial velocity monitoring, and 3 nights of high-cadence HARPS asteroseismic data. We construct a high-S/N HARPS spectrum that we use to determine atmospheric parameters and chemical composition. Spectra observed at different rotation phases are analyzed to search for signs of temperature or abundance variations. An upper limit on the projected rotational velocity is derived from very high-resolution CES spectra. Results: We detect oscillations in EK Eri with a frequency of the maximum power of ν_max = 320 ± 32 μHz, and we derive a peak amplitude per radial mode of ≈0.15 m s-1, which is a factor of ≈3 lower than expected. We suggest that the magnetic field may act to suppress low-degree modes. Individual frequencies can not be extracted from the available data. We derive accurate atmospheric parameters, refining our previous analysis, finding T_eff = 5135 ± 80 K, log g = 3.39 ± 0.12, and metallicity [M/H] = + 0.02 ± 0.04. Mass and radius estimates from the seismic analysis are not accurate enough to constrain the position in the HR diagram and the evolutionary state. We confirm that the main light variation is due to cool spots, but that other contributions may need to be taken into account. We tentatively suggest that the rotation period is twice the photometric period, i.e., P_rot = 2P_phot = 617.6 d, and that the star is a dipole-dominated oblique rotator viewed close to equator-on. We conclude from our derived parameters that v sin i < 0.40 km s-1 and we show that the value is too low to be reliably measured. We also link the time series of direct magnetic field measurements available in the literature

  7. Red Dwarf Stars: Ages, Rotation, Magnetic Dynamo Activity and the Habitability of Hosted Planets

    NASA Astrophysics Data System (ADS)

    Engle, S. G.; Guinan, E. F.

    2011-12-01

    We report on our continued efforts to understand and delineate the magnetic dynamo-induced behavior/variability of red dwarf (K5 V - M6 V) stars over their long lifetimes. These properties include: rotation, light variations (from star spots), coronal-chromospheric XUV activity and flares. This study is being carried out as part of the NSF-sponsored Living with a Red Dwarf program. The Living with a Red Dwarf program's database of dM stars with photometrically determined rotation rates (from starspot modulations) continues to expand, as does the inventory of archival XUV observations. Recently, the photometric properties of several hundred dM stars from the Kepler database are being analyzed to determine the rotation rates, starspot areal coverage/distributions and stellar flare rates. When all data setsare combined with ages from cluster/population memberships and kinematics, the determination of Age-Rotation-Activity relationships is possible. Such relationships have broad impacts not only on the studies of magnetic dynamo theory and angular momentum loss of low-mass stars with deep convective zones, but also on the suitability of planets hosted by red dwarfs to support life. With intrinsically low luminosities (L< 0.02L⊙), the liquid water habitable zones (HZs) for hosted planets are very close to their host stars - typically at ˜0.1 AU < HZ < 0.4 AU. Planets located close to their host stars risk damage and atmospheric loss from coronal & chromospheric XUV radiation, flares and plasma blasts via strong winds and coronal mass ejections. In addition, our relationships permit the stellar ages to be determined through measures of either the stars' rotation periods (best way) or XUV activity levels. This also permits a determination of the ages of their hosted planets. We illustrate this with examples of age determinations of the exoplanet systems: GJ 581 and HD 85512 (both with large Earth-size planets within the host star's HZ), GJ 1214 (hot, close

  8. Surface electromyography activity of the rectus abdominis, internal oblique, and external oblique muscles during forced expiration in healthy adults.

    PubMed

    Ito, Kenichi; Nonaka, Koji; Ogaya, Shinya; Ogi, Atsushi; Matsunaka, Chiaki; Horie, Jun

    2016-06-01

    We aimed to characterize rectus abdominis, internal oblique, and external oblique muscle activity in healthy adults under expiratory resistance using surface electromyography. We randomly assigned 42 healthy adult subjects to 3 groups: 30%, 20%, and 10% maximal expiratory intraoral pressure (PEmax). After measuring 100% PEmax and muscle activity during 100% PEmax, the activity and maximum voluntary contraction of each muscle during the assigned experimental condition were measured. At 100% PEmax, the external oblique (p<0.01) and internal oblique (p<0.01) showed significantly elevated activity compared with the rectus abdominis muscle. Furthermore, at 20% and 30% PEmax, the external oblique (p<0.05 and<0.01, respectively) and the internal oblique (p<0.05 and<0.01, respectively) showed significantly elevated activity compared with the rectus abdominis muscle. At 10% PEmax, no significant differences were observed in muscle activity. Although we observed no significant difference between 10% and 20% PEmax, activity during 30% PEmax was significantly greater than during 20% PEmax (external oblique: p<0.05; internal oblique: p<0.01). The abdominal oblique muscles are the most active during forced expiration. Moreover, 30% PEmax is the minimum intensity required to achieve significant, albeit very slight, muscle activity during expiratory resistance.

  9. Anti-solar differential rotation on the active sub-giant HU Virginis

    NASA Astrophysics Data System (ADS)

    Harutyunyan, G.; Strassmeier, K. G.; Künstler, A.; Carroll, T. A.; Weber, M.

    2016-08-01

    Context. Measuring surface differential rotation (DR) on different types of stars is important when characterizing the underlying stellar dynamo. It has been suggested that anti-solar DR laws can occur when strong meridional flows exist. Aims: We aim to investigate the differential surface rotation on the primary star of the RS CVn binary, HU Vir, by tracking its starspot distribution as a function of time. We also aim to recompute and update the values for several system parameters of the triple system HU Vir (close and wide orbits). Methods: Time-series high-resolution spectroscopy for four continuous months was obtained with the 1.2-m robotic STELLA telescope. Nine consecutive Doppler images were reconstructed from these data, using our line-profile inversion code iMap. An image cross-correlation method was applied to derive the surface differential-rotation law for HU Vir. New orbital elements for the close and the wide orbits were computed using our new STELLA radial velocities (RVs) combined with the RV data available in the literature. Photometric observations were performed with the Amadeus Automatic Photoelectric Telescope (APT), providing contemporaneous Johnson-Cousins V and I data for approximately 20 yrs. This data was used to determine the stellar rotation period and the active longitudes. Results: We confirm anti-solar DR with a surface shear parameter α of -0.029 ± 0.005 and -0.026 ± 0.009, using single-term and double-term differential rotation laws, respectively. These values are in good agreement with previously claimed results. The best fit is achieved assuming a solar-like double-term law with a lap time of ≈400 d. Our orbital solutions result in a period of 10.387678 ± 0.000003 days for the close orbit and 2726 ± 7 d (≈7.5 yr) for the wide orbit. A Lomb-Scarge (L-S) periodogram of the pre-whitened V-band data reveals a strong single peak providing a rotation period of 10.391 ± 0.008 d, well synchronized to the short orbit. Based on

  10. Suppressed catalytic activity of base excision repair enzymes on rotationally positioned uracil in nucleosomes.

    PubMed

    Beard, Brian C; Wilson, Samuel H; Smerdon, Michael J

    2003-06-24

    The majority of DNA in eukaryotic cells exists in the highly condensed structural hierarchy of chromatin, which presents a challenge to DNA repair enzymes in that recognition, incision, and restoration of the original sequence at most sites must take place within these structural constraints. To test base excision repair (BER) activities on chromatin substrates, an in vitro system was developed that uses human uracil DNA glycosylase (UDG), apyrimidinic/apurinic endonuclease (APE), and DNA polymerase beta (pol beta) on homogeneously damaged, rotationally positioned DNA in nucleosomes. We find that UDG and APE carry out their combined catalytic activities with reduced efficiency on nucleosome substrates ( approximately 10% of that on naked DNA). Furthermore, these enzymes distinguish between two different rotational settings of the lesion on the histone surface, showing a 2- to 3-fold difference in activity between uracil facing "toward" and "away from" the histones. However, UDG and APE will digest such substrates to completion in a concentration-dependent manner. Conversely, the synthesis activity of pol beta is inhibited completely by nucleosome substrates and is independent of enzyme concentration. These results suggest that the first two steps of BER, UDG and APE, may occur "unassisted" in chromatin, whereas downstream factors in this pathway (i.e., pol beta) may require nucleosome remodeling for efficient DNA BER in at least some regions of chromatin in eukaryotic cells.

  11. Experimental and theoretical analyses of penetration processes of externally applied rotating helical magnetic perturbation fields in TEXTOR and HYBTOK-II

    NASA Astrophysics Data System (ADS)

    Kikuchi, Y.; de Bock, M. F. M.; Finken, K. H.; Jakubowski, M.; Jaspers, R.; Koslowski, H. R.; Kraemer-Flecken, A.; Lehnen, M.; Liang, Y.; Loewenbrueck, K.; Matsunaga, G.; Reiser, D.; Samm, U.; Sewell, G.; Takamura, S.; Unterberg, B.; Wolf, R. C.; Zimmermann, O.; TEXTOR-team

    2007-05-01

    Penetration processes of rotating helical magnetic perturbation field into tokamak plasmas have been investigated by the dynamic ergodic divertor (DED) in TEXTOR. Experimental observations of the field penetration and field amplification are performed and the data are interpreted by theoretical analyses based on a linearized two-fluid plasma model. It is observed that the growth of the forced magnetic reconnection by the rotating DED-field is accompanied by a change in the plasma fluid rotation. The theoretical model is also applied to the DED experiment in the small tokamak device HYBTOK-II. It is confirmed that the theoretical analyses can explain the observed radial profiles of the DED-field in the plasma by inserting small magnetic pick-up coils in HYBTOK-II.

  12. Adsorption and Catalytic Activity of Glucose Oxidase Accumulated on OTCE upon the Application of External Potential

    PubMed Central

    Benavidez, Tomás E.; Torrente, Daniel; Marucho, Marcelo; Garcia, Carlos D.

    2014-01-01

    This article describes the adsorption of glucose oxidase (GOx) onto optically transparent carbon electrodes (OTCE) under the effect of applied potential and the analysis of the enzymatic activity of the resulting GOx/OTCE substrates. In order to avoid electrochemical interferences with the enzyme redox center, control electrochemical experiments were performed using flavin adenine dinucleotide (FAD) and GOx/OTCE substrates. Then, the enzyme adsorption experiments were carried out as a function of the potential applied (ranged from the open circuit potential to +950 mV), the pH solution, the concentration of enzyme, and the ionic strength on the environment. The experimental results demonstrated that an increase in the adsorbed amount of GOx on the OTCE can be achieved when the potential was applied. Although the increase in the adsorbed amount was examined as a function of the potential, a maximum enzymatic activity was observed in the GOx/OTCE substrate achieved at +800 mV. These experiments suggest that although an increase in the amount of enzyme adsorbed can be obtained by the application of an external potential to the electrode, the magnitude of such potential can produce detrimental effects in the conformation of the adsorbed protein and should be carefully considered. As such, the article describes a simple and rational approach to increase the amount of enzyme adsorbed on a surface and can be applied to improve the sensitivity of a variety of biosensors. PMID:25261840

  13. Low-mass ultra-cool dwarfs: Atmospheres, rotation and magnetic activity

    NASA Astrophysics Data System (ADS)

    Mohanty, Subhanjoy

    Low-mass stars and substellar brown dwarfs are the most numerous luminous components of our Galaxy. In order to motivate my research, I begin in Chapter 1 with a review of the M and L spectral types. These spectral classes are the focus of my thesis, since they define the transition from stellar to substellar regimes. In Chapter 2, I attempt to determine the effective temperature of a sample of late M and L dwarfs, by profile fitting the atomic resonance absorption lines of Cesium and Rubidium. An effective temperature scale is devised, assuming constant surface gravity and solar metallicity. In order to investigate more carefully the interplay between effective temperature, gravity and dust formation, I embark in Chapter 3 on a multi-feature spectral analysis of cool M dwarfs. We find that individual spectral features may be degenerate in their response to variations in gravity, temperature and dust. However, the latter parameters can be uniquely determined by a simultaneous examination of multiple lines, such as those of TiO, Na, Cs and FeI. Keeping the above results in mind, I examine, in Chapter 4, the trends in rotation and activity in cool dwarfs. Rotation and chromospheric activity observations are presented for nearly one hundred mid-M to mid-L dwarfs. We find that rotation rates continue to increase with later type. Using a Reynolds number calculation, we show that a decrease in ionization fraction can indeed lead to the observed falloff in activity levels, in the late M and L dwarfs. Acoustic heating effects are also examined. We suggest some possibilities to explain the recently discovered coronal radio emission in these objects. Finally, we propose a mechanism to explain the intermittent flaring that is also observed at these spectral types. (Abstract shortened by UMI.)

  14. Increased movement accuracy and reduced EMG activity as the result of adopting an external focus of attention.

    PubMed

    Zachry, Tiffany; Wulf, Gabriele; Mercer, John; Bezodis, Neil

    2005-10-30

    The performance and learning of motor skills has been shown to be enhanced if the performer adopts an external focus of attention (focus on the movement effect) compared to an internal focus (focus on the movements themselves) [G. Wulf, W. Prinz, Directing attention to movement effects enhances learning: a review, Psychon. Bull. Rev. 8 (2001) 648-660]. While most previous studies examining attentional focus effects have exclusively used performance outcome (e.g., accuracy) measures, in the present study electromyography (EMG) was used to determine neuromuscular correlates of external versus internal focus differences in movement outcome. Participants performed basketball free throws under both internal focus (wrist motion) and external focus (basket) conditions. EMG activity was recorded for m. flexor carpi radialis, m. biceps brachii, m. triceps triceps brachii, and m. deltoid of each participant's shooting arm. The results showed that free throw accuracy was greater when participants adopted an external compared to an internal focus. In addition, EMG activity of the biceps and triceps muscles was lower with an external relative to an internal focus. This suggests that an external focus of attention enhances movement economy, and presumably reduces "noise" in the motor system that hampers fine movement control and makes the outcome of the movement less reliable.

  15. Parkinsonian beta oscillations in the external globus pallidus and their relationship with subthalamic nucleus activity.

    PubMed

    Mallet, Nicolas; Pogosyan, Alek; Márton, László F; Bolam, J Paul; Brown, Peter; Magill, Peter J

    2008-12-24

    Inappropriately synchronized beta (beta) oscillations (15-30 Hz) in the subthalamic nucleus (STN) accompany movement difficulties in idiopathic Parkinson's disease (PD). The cellular and network substrates underlying these exaggerated beta oscillations are unknown but activity in the external globus pallidus (GP), which forms a candidate pacemaker network with STN, might be of particular importance. Using a clinically relevant rat model of PD, we demonstrate that oscillatory activity in GP neuronal networks becomes excessively and selectively synchronized at beta frequencies in a spatially widespread and brain state-dependent manner after lesion of dopamine neurons. Although synchronization of GP unit activity increased by almost 100-fold during beta oscillations, the mean firing rate of GP neurons decreased compared with controls. Importantly, in parkinsonian animals, two main types of GP neuron were identified according to their distinct and inversely related firing rates and patterns. Moreover, neurons of the same type tended to fire together, with small phase differences, whereas different types of neuron tended not to do so. This functional dichotomy in temporal coupling persisted across extreme brain states, suggesting that maladaptive interactions are dominated by hardwiring. Finally, the precisely timed discharges of GP and STN neurons indicated that rhythmic sequences of recurrent excitation and inhibition in the STN-GP network, and lateral inhibition between GP neurons, could actively support abnormal beta oscillations. We propose that GP neurons, by virtue of their spatiotemporal synchronization, widespread axon collaterals and feed-back/feed-forward mechanisms, are well placed to orchestrate and propagate exaggerated beta oscillations throughout the entire basal ganglia in PD. PMID:19109506

  16. Experimental investigation of the external nitrification biological nutrient removal activated sludge (ENBNRAS) system.

    PubMed

    Hu, Zhi-Rong; Sötemann, S; Moodley, R; Wentzel, M C; Ekama, G A

    2003-08-01

    A systematic lab-scale experimental investigation is reported for the external nitrification (EN) biological nutrient removal (BNR) activated sludge (ENBNRAS) system, which is a combined fixed and suspended medium system. The ENBNRAS system was proposed to intensify the treatment capacity of BNR-activated sludge (BNRAS) systems by addressing two difficulties often encountered in practice: (a) the long sludge age for nitrification requirement; and (b) sludge bulking. In the ENBNRAS system, nitrification is transferred from the aerobic reactor in the suspended medium activated sludge system to a fixed medium nitrification system. Thus, the sludge age of the suspended medium activated sludge system can be reduced from 20 to 25 days to 8 to 10 days, resulting in a decrease in reactor volume per ML wastewater treated of about 30%. Furthermore, the aerobic mass fraction can also be reduced from 50% to 60% to <30% and concommitantly the anoxic mass fraction can be increased from 25% to 35% to >55% (if the anaerobic mass fraction is 15%), and thus complete denitrification in the anoxic reactors becomes possible. Research indicates that both the short sludge age and complete denitrification could ameliorate anoxic aerobic (AA) or low food/microorganism (F/M) ratio filamentous bulking, and hence reduce the surface area of secondary settling tanks or increase the treatment capacity of existing systems. The lab-scale experimental investigations indicate that the ENBNRAS system can obtain: (i) very good chemical oxygen demand (COD) removal, even with an aerobic mass fraction as low as 20%; (ii) high nitrogen removal, even for a wastewater with a high total kjeldahl nitrogen (TKN)/COD ratio, up to 0.14; (iii) adequate settling sludge (diluted sludge volume index [DSVI] <100 mL/g); and (iv) a significant reduction in oxygen demand.

  17. Heat and mass transfer in unsteady rotating fluid flow with binary chemical reaction and activation energy.

    PubMed

    Awad, Faiz G; Motsa, Sandile; Khumalo, Melusi

    2014-01-01

    In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. PMID:25250830

  18. Heat and Mass Transfer in Unsteady Rotating Fluid Flow with Binary Chemical Reaction and Activation Energy

    PubMed Central

    Awad, Faiz G.; Motsa, Sandile; Khumalo, Melusi

    2014-01-01

    In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. PMID:25250830

  19. Improving active seismic isolation in aLIGO using a ground rotation sensor

    NASA Astrophysics Data System (ADS)

    Venkateswara, Krishna; Hagedorn, Charles; Ross, Michael; Gundlach, Jens

    2016-03-01

    The active seismic isolation in Advanced LIGO achieves a factor of 10 -104 isolation from ground displacement in the frequency range from 0.1-10 Hz enabling stable low noise interferometer operation. It uses seismometers on the ground and the optics platform in feedback loops to reduce the transmission of ground motion to the platform. However, due to the inability of a seismometer to distinguish between horizontal acceleration and rotation (coupling through gravity), wind-induced tilt limits the performance of the active isolation in the 10-500 mHz frequency range, thereby reducing the duty-cycle of the detectors. We describe a ground rotation sensor, consisting of a low frequency beam-balance and an autocollimator readout with better than 0.4 nrad/rt(Hz) sensitivity above 10 mHz, which can be used to subtract tilt-noise from a horizontal seismometer, thus improving the active seismic isolation system. This work was supported by NSF Grant: 1306613.

  20. Activation of transmembrane cell‐surface receptors via a common mechanism? The “rotation model”

    PubMed Central

    2015-01-01

    It has long been thought that transmembrane cell‐surface receptors, such as receptor tyrosine kinases and cytokine receptors, among others, are activated by ligand binding through ligand‐induced dimerization of the receptors. However, there is growing evidence that prior to ligand binding, various transmembrane receptors have a preformed, yet inactive, dimeric structure on the cell surface. Various studies also demonstrate that during transmembrane signaling, ligand binding to the extracellular domain of receptor dimers induces a rotation of transmembrane domains, followed by rearrangement and/or activation of intracellular domains. The paper here describes transmembrane cell‐surface receptors that are known or proposed to exist in dimeric form prior to ligand binding, and discusses how these preformed dimers are activated by ligand binding. PMID:26241732

  1. RELATING CHANGES IN COMETARY ROTATION TO ACTIVITY: CURRENT STATUS AND APPLICATIONS TO COMET C/2012 S1 (ISON)

    SciTech Connect

    Samarasinha, Nalin H.; Mueller, Béatrice E. A.

    2013-09-20

    We introduce a parameter, X, to predict the changes in the rotational period of a comet in terms of the rotational period itself, the nuclear radius, and the orbital characteristics. We show that X should be a constant if the bulk densities and shapes of nuclei are nearly identical and the activity patterns are similar for all comets. For four nuclei for which rotational changes are well documented, despite the nearly factor 30 variation observed among the effective active fractions of these comets, X is constant to within a factor two. We present an analysis for the sungrazing comet C/2012 S1 (ISON) to explore what rotational changes it could undergo during the upcoming perihelion passage where its perihelion distance will be ∼2.7 solar radii. When close to the Sun, barring a catastrophic disruption of the nucleus, the activity of ISON will be sufficiently strong to put the nucleus into a non-principal-axis rotational state and observable changes to the rotational period should also occur. Additional causes for rotational state changes near perihelion for ISON are tidal torques caused by the Sun and the significant mass loss due to a number of mechanisms resulting in alterations to the moments of inertia of the nucleus.

  2. External carbonic anhydrase in three Caribbean corals: quantification of activity and role in CO2 uptake

    NASA Astrophysics Data System (ADS)

    Tansik, Anna L.; Fitt, William K.; Hopkinson, Brian M.

    2015-09-01

    Scleractinian corals have complicated inorganic carbon ( C i) transport pathways to support both photosynthesis, by their symbiotic dinoflagellates, and calcification. The first step in C i acquisition, uptake into the coral, is critical as the diffusive boundary layer limits the supply of CO2 to the surface and HCO3 - uptake is energy intensive. An external carbonic anhydrase (eCA) on the oral surface of corals is thought to facilitate CO2 uptake by converting HCO3 - into CO2, helping to overcome the limitation imposed by the boundary layer. However, this enzyme has not yet been identified or detected in corals, nor has its activity been quantified. We have developed a method to quantify eCA activity using a reaction-diffusion model to analyze data on 18O removal from labeled C i. Applying this technique to three species of Caribbean corals ( Orbicella faveolata, Porites astreoides, and Siderastrea radians) showed that all species have eCA and that the potential rates of CO2 generation by eCA greatly exceed photosynthetic rates. This demonstrates that eCA activity is sufficient to support its hypothesized role in CO2 supply. Inhibition of eCA severely reduces net photosynthesis in all species (on average by 46 ± 27 %), implying that CO2 generated by eCA is a major carbon source for photosynthesis. Because of the high permeability of membranes to CO2, CO2 uptake is likely driven by a concentration gradient across the cytoplasmic membrane. The ubiquity of eCA in corals from diverse genera and environments suggests that it is fundamental for photosynthetic CO2 supply.

  3. An underwater superoleophobic surface that can be activated/deactivated via external triggers.

    PubMed

    Dunderdale, Gary J; Urata, Chihiro; Hozumi, Atsushi

    2014-11-11

    Poly[(2-dimethylamino)ethyl methacrylate] (pDMAEMA) brush surfaces were prepared using a facile aqueous Activators ReGenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET-ATRP) protocol at ambient temperature without any need to purge reaction solutions of oxygen. This produced underwater superoleophobic surfaces, which exhibited high advancing (θA, 164-166°) and receding (θR, 153-165°) contact angles (CAs) and low CA hysteresis (1-11°) with a variety of oils. Both in situ spectroscopic ellipsometry and dynamic CA measurements confirmed that pDMAEMA brush surfaces responded to three different external stimuli (pH, ionic strength, and temperature) by changing their thicknesses, degree of hydration, or their chemical composition. Increasing pH resulted in the largest decrease in hydration, followed by increasing temperature, and increasing ionic strength gave the smallest change in hydration. Coincident with these structural changes, stimulus-responsive dynamic dewetting behavior with various oils was observed. Increasing pH or ionic strength drastically reduced the θR values of oil drops and increased CA hysteresis, resulting in a sticky surface on which oil drops were pinned. No noticeable changes in dynamic oleophobicity were observed with increasing temperature. In addition, when oil drops impacted onto the brush surface instead of being gently placed, surfaces did not exhibit stimulus-responsive dewetting properties, being oleophobic under all conditions. PMID:25318101

  4. Hebbian Plasticity Realigns Grid Cell Activity with External Sensory Cues in Continuous Attractor Models

    PubMed Central

    Mulas, Marcello; Waniek, Nicolai; Conradt, Jörg

    2016-01-01

    After the discovery of grid cells, which are an essential component to understand how the mammalian brain encodes spatial information, three main classes of computational models were proposed in order to explain their working principles. Amongst them, the one based on continuous attractor networks (CAN), is promising in terms of biological plausibility and suitable for robotic applications. However, in its current formulation, it is unable to reproduce important electrophysiological findings and cannot be used to perform path integration for long periods of time. In fact, in absence of an appropriate resetting mechanism, the accumulation of errors over time due to the noise intrinsic in velocity estimation and neural computation prevents CAN models to reproduce stable spatial grid patterns. In this paper, we propose an extension of the CAN model using Hebbian plasticity to anchor grid cell activity to environmental landmarks. To validate our approach we used as input to the neural simulations both artificial data and real data recorded from a robotic setup. The additional neural mechanism can not only anchor grid patterns to external sensory cues but also recall grid patterns generated in previously explored environments. These results might be instrumental for next generation bio-inspired robotic navigation algorithms that take advantage of neural computation in order to cope with complex and dynamic environments. PMID:26924979

  5. An underwater superoleophobic surface that can be activated/deactivated via external triggers.

    PubMed

    Dunderdale, Gary J; Urata, Chihiro; Hozumi, Atsushi

    2014-11-11

    Poly[(2-dimethylamino)ethyl methacrylate] (pDMAEMA) brush surfaces were prepared using a facile aqueous Activators ReGenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET-ATRP) protocol at ambient temperature without any need to purge reaction solutions of oxygen. This produced underwater superoleophobic surfaces, which exhibited high advancing (θA, 164-166°) and receding (θR, 153-165°) contact angles (CAs) and low CA hysteresis (1-11°) with a variety of oils. Both in situ spectroscopic ellipsometry and dynamic CA measurements confirmed that pDMAEMA brush surfaces responded to three different external stimuli (pH, ionic strength, and temperature) by changing their thicknesses, degree of hydration, or their chemical composition. Increasing pH resulted in the largest decrease in hydration, followed by increasing temperature, and increasing ionic strength gave the smallest change in hydration. Coincident with these structural changes, stimulus-responsive dynamic dewetting behavior with various oils was observed. Increasing pH or ionic strength drastically reduced the θR values of oil drops and increased CA hysteresis, resulting in a sticky surface on which oil drops were pinned. No noticeable changes in dynamic oleophobicity were observed with increasing temperature. In addition, when oil drops impacted onto the brush surface instead of being gently placed, surfaces did not exhibit stimulus-responsive dewetting properties, being oleophobic under all conditions.

  6. The Effects of Close Companions (and Rotation) on the Magnetic Activity of M Dwarfs

    NASA Astrophysics Data System (ADS)

    Morgan, Dylan P.; West, Andrew A.; Garcés, Ane; Catalán, Silvia; Dhital, Saurav; Fuchs, Miriam; Silvestri, Nicole M.

    2012-10-01

    We present a study of close white dwarf and M dwarf (WD+dM) binary systems and examine the effect that a close companion has on the magnetic field generation in M dwarfs. We use a base sample of 1602 white dwarf main-sequence binaries from Rebassa-Mansergas et al. to develop a set of color cuts in GALEX, SDSS, UKIDSS, and 2MASS color space. Then using the SDSS Data Release 8 spectroscopic database, we construct a sample of 1756 WD+dM high-quality pairs from our color cuts and previous catalogs. We separate the individual WD and dM from each spectrum using an iterative technique that compares the WD and dM components to best-fit templates. Using the absolute height above the Galactic plane as a proxy for age, and the Hα emission line as an indicator for magnetic activity, we investigate the age-activity relation for our sample for spectral types <= M7. Our results show that early-type M dwarfs (<=M4) in close binary systems are more likely to be active and have longer activity lifetimes compared to their field counterparts. However, at a spectral type of M5 (just past the onset of full convection in M dwarfs), the activity fraction and lifetimes of WD+dM binary systems become more comparable to that of the field M dwarfs. One of the implications of having a close binary companion is presumed to be increased stellar rotation through disk disruption, tidal effects, or angular momentum exchange. Thus, we interpret the similarity in activity behavior between late-type dMs in WD+dM pairs and late-type field dMs to be due to a decrease in sensitivity in close binary companions (or stellar rotation), which has implications for the nature of magnetic activity in fully convective stars. Using the WD components of the pairs, we find WD cooling ages to use as an additional constraint on the age-activity relation for our sample. We find that, on average, active early-type dMs tend to be younger and that active late-type dMs span a much broader age regime making them

  7. THE EFFECTS OF CLOSE COMPANIONS (AND ROTATION) ON THE MAGNETIC ACTIVITY OF M DWARFS

    SciTech Connect

    Morgan, Dylan P.; West, Andrew A.; Dhital, Saurav; Fuchs, Miriam; Garces, Ane; Catalan, Silvia; Silvestri, Nicole M.

    2012-10-01

    We present a study of close white dwarf and M dwarf (WD+dM) binary systems and examine the effect that a close companion has on the magnetic field generation in M dwarfs. We use a base sample of 1602 white dwarf main-sequence binaries from Rebassa-Mansergas et al. to develop a set of color cuts in GALEX, SDSS, UKIDSS, and 2MASS color space. Then using the SDSS Data Release 8 spectroscopic database, we construct a sample of 1756 WD+dM high-quality pairs from our color cuts and previous catalogs. We separate the individual WD and dM from each spectrum using an iterative technique that compares the WD and dM components to best-fit templates. Using the absolute height above the Galactic plane as a proxy for age, and the H{alpha} emission line as an indicator for magnetic activity, we investigate the age-activity relation for our sample for spectral types {<=} M7. Our results show that early-type M dwarfs ({<=}M4) in close binary systems are more likely to be active and have longer activity lifetimes compared to their field counterparts. However, at a spectral type of M5 (just past the onset of full convection in M dwarfs), the activity fraction and lifetimes of WD+dM binary systems become more comparable to that of the field M dwarfs. One of the implications of having a close binary companion is presumed to be increased stellar rotation through disk disruption, tidal effects, or angular momentum exchange. Thus, we interpret the similarity in activity behavior between late-type dMs in WD+dM pairs and late-type field dMs to be due to a decrease in sensitivity in close binary companions (or stellar rotation), which has implications for the nature of magnetic activity in fully convective stars. Using the WD components of the pairs, we find WD cooling ages to use as an additional constraint on the age-activity relation for our sample. We find that, on average, active early-type dMs tend to be younger and that active late-type dMs span a much broader age regime making them

  8. The Light-Curve and Rotation Rate of 'Active Asteroid' 313P/Gibbs

    NASA Astrophysics Data System (ADS)

    Milewski, Dave Gerald

    2016-10-01

    The 'Active Asteroids' are a strange, yet newly discovered class of small bodies in the Solar System that have the orbital and dynamical properties of asteroids, but also the physical properties of comets (ejection of dust and volatile materials). Of the known ~25 Active Asteroids discovered thus far (Jewitt, Hseih, Argwal, 2015), only 4 have been known to be active on subsequent multiple occasions 238P/Read, 133P/Elst-Pizarro, 324P/La Sagra, (Jewitt et al. 2016) and 313P/Gibbs. In this work, we have determined the rotation rate and light-curve for Active Asteroid 313P/Gibbs using the Keck 10-m telescope to better understand the mechanisms and drivers of subsequent activity in this Solar System Small Body so that we may form a more complete picture of this population, better characterize them, and add to our inventory of Solar System small bodies to form a more complete model of the formation of the Solar System as well as what this may imply for future detection of activity in the Active Asteroid population.

  9. Intrinsic rotation due to MHD activity in a tokamak with a resistive wall

    NASA Astrophysics Data System (ADS)

    Haines, M. G.; Gimblett, C. G.; Hastie, R. J.

    2013-05-01

    MHD activity in a tokamak, in the form of waves and instabilities, generally has a preferred direction for propagation in a two-fluid plasma. When the radial component of magnetic field associated with this activity interacts with a resistive wall, momentum or angular momentum will be given to the wall. The equal and opposite reaction will be on the plasma, in particular, for ideal and resistive modes, at the singular or resonant surfaces for the various modes. In this case the torque exerted is electromagnetic. This is in contrast to other mechanisms for intrinsic or spontaneous rotation which may arise at the plasma boundary. The resistive wall is considered generally, and the thin and thick wall limits found, the latter being relevant to ITER parameters. Remarkably small radial perturbing fields of order 0.1 G could produce a torque comparable in effect to the apparent anomalous toroidal viscosity.

  10. Rotation sensing with Er3+-doped active ring resonator slow light structure

    NASA Astrophysics Data System (ADS)

    Gu, Hong; Liu, Xiaoqin

    2016-10-01

    An optical gyroscope, which is constituted by Er3+-doped active ring resonator (EDARR) slow light structure, is presented for the first time. The principle of improving the sensitivity of the detection of angular velocity is analysed in detail. The expression of the rotation phase difference of EDARR between the counter-propagating waves is derived and discussed. At the resonant frequency, the phase shift difference has the maximum value when the light power in the cavity is far greater than the input light power. We designed an experimental scheme of Er3+-doped active ring resonator slow light system. Two additional bias phases ϕb = ±π/2 were introduced in the optical path, by recording the light intensity difference ? and I0 at the resonant frequency ?, the input angular velocity can be obtained. The slow light structure based on EDARR can enhance the sensitivity of the detection of the angular velocity by three orders of magnitude.

  11. PARSEC-SCALE FARADAY ROTATION MEASURES FROM GENERAL RELATIVISTIC MAGNETOHYDRODYNAMIC SIMULATIONS OF ACTIVE GALACTIC NUCLEUS JETS

    SciTech Connect

    Broderick, Avery E.; McKinney, Jonathan C. E-mail: jmckinne@stanford.ed

    2010-12-10

    It is now possible to compare global three-dimensional general relativistic magnetohydrodynamic (GRMHD) jet formation simulations directly to multi-wavelength polarized VLBI observations of the pc-scale structure of active galactic nucleus (AGN) jets. Unlike the jet emission, which requires post hoc modeling of the nonthermal electrons, the Faraday rotation measures (RMs) depend primarily upon simulated quantities and thus provide a direct way to confront simulations with observations. We compute RM distributions of a three-dimensional global GRMHD jet formation simulation, extrapolated in a self-consistent manner to {approx}10 pc scales, and explore the dependence upon model and observational parameters, emphasizing the signatures of structures generic to the theory of MHD jets. With typical parameters, we find that it is possible to reproduce the observed magnitudes and many of the structures found in AGN jet RMs, including the presence of transverse RM gradients. In our simulations, the RMs are generated in the circum-jet material, hydrodynamically a smooth extension of the jet itself, containing ordered toroidally dominated magnetic fields. This results in a particular bilateral morphology that is unlikely to arise due to Faraday rotation in distant foreground clouds. However, critical to efforts to probe the Faraday screen will be resolving the transverse jet structure. Therefore, the RMs of radio cores may not be reliable indicators of the properties of the rotating medium. Finally, we are able to constrain the particle content of the jet, finding that at pc scales AGN jets are electromagnetically dominated, with roughly 2% of the comoving energy in nonthermal leptons and much less in baryons.

  12. Rotationally induced surface slope-instabilities and the activation of CO2 activity on comet 103P/Hartley 2

    NASA Astrophysics Data System (ADS)

    Steckloff, Jordan K.; Graves, Kevin; Hirabayashi, Masatoshi; Melosh, H. Jay; Richardson, James E.

    2016-07-01

    Comet 103P/Hartley 2 has diurnally controlled, CO2-driven activity on the tip of the small lobe of its bilobate nucleus. Such activity is unique among the comet nuclei visited by spacecraft, and suggests that CO2 ice is very near the surface, which is inconsistent with our expectations of an object that thermophysically evolved for ∼45 million years prior to entering the Jupiter Family of comets. Here we explain this pattern of activity by showing that a very plausible recent episode of rapid rotation (rotation period of ∼11 [10-13] h) would have induced avalanches in Hartley 2's currently active regions that excavated down to CO2-rich ices and activated the small lobe of the nucleus. At Hartley 2's current rate of spindown about its principal axis, the nucleus would have been spinning fast enough to induce avalanches ∼3-4 orbits prior to the DIXI flyby (∼1984-1991). This coincides with Hartley 2's discovery in 1986, and implies that the initiation of CO2 activity facilitated the comet's discovery. During the avalanches, the sliding material would either be lofted off the surface by gas activity, or possibly gained enough momentum moving downhill (toward the tip of the small lobe) to slide off the tip of the small lobe. Much of this material would have failed to reach escape velocity, and would reimpact the nucleus, forming debris deposits. The similar size frequency distribution of the mounds observed on the surface of Hartley 2 and chunks of material in its inner coma suggest that the 20-40 m mounds observed by the DIXI mission on the surface of Hartley 2 are potentially these fallback debris deposits. As the nucleus spun down (rotation period increased) from a period of ∼11-18.34 h at the time of the DIXI flyby, the location of potential minima, where materials preferentially settle, migrated about the surface, allowing us to place relative ages on most of the terrains on the imaged portion of the nucleus.

  13. Effectiveness of Group Activity Play Therapy on Internalizing and Externalizing Behavior Problems of Preadolescent Orphans in Uganda

    ERIC Educational Resources Information Center

    Ojiambo, Deborah

    2011-01-01

    This pilot study investigated the impact of group activity play therapy (GAPT) on displaced orphans aged 10 to 12 years living in a large children's village in Uganda. Teachers and housemothers identified 60 preadolescents exhibiting clinical levels of internalizing and externalizing behavior problems. The participants' ethnicity was…

  14. Periods of the Earth's seismicity activation and their relationship to variations in the Earth's rotation velocity

    NASA Astrophysics Data System (ADS)

    Sasorova, Elena; Levin, Boris

    2015-04-01

    It is known that Earth's seismic activity (SA) demonstrates distinct roughness (nonuniformity) in time. Periods of intensification of the SA followed by periods of its decaying. For strong earthquakes these periods are continued several decades. It was also noted that there is a pronounced periodic amplification and attenuation of the SA with a period of about 30 years, which is manifested mainly in two latitudinal belts 50°N-30°N and 0°-30°S [Levin, Sasorova, 2014, 2015]. This work deals with the hypothesis that it is the properties of rotating non-uniform rate of the planet may be the cause of the periodicity of manifestations SA. The objective of this work is the searching of the spatial-temporal interconnection between the Earth rotation irregularity and the observed cyclic increasing and decreasing of the Earth's SA. This requires preparation a long series of observations of seismic events with representative data sets (EQ selected from 1895 up to date with a magnitude M> = 7.5, based on the catalog NEIC). Two sources of data on the angular velocity of the Earth's rotation of (length of day, LOD) were adapted: the world-known database IERS (Annual Report, International Earth Rotation Service) and the data, which were presented in the work (McCarthy, D.D., and Babcock A.K., 1986). The first one contains daily observations from 1962 to 2013, the second one was identified semi-annual observations from 1720 to 1984. It was prepared concatenated data set (CLOD) for the period from 1720 to 2013. Characteristic periods in the time series CLOD: 62, 32, and 23 years have been isolated by the use of spectral analysis. Next, it were used a band-pass filters for the four frequency bands from 124 to 45 years, from 37 do 25 years, from 25 to 19 years, and in the range of less than 19 years. In the frequency bands 37-25 years and 25-19 years marked clear periodic oscillations close to a sine wave. The amplitude of the oscillations with the 1720 to 1790 gradually

  15. Shoulder rotators electro-mechanical properties change with intensive volleyball practice: a pilot study.

    PubMed

    Cornu, C; Nordez, A; Bideau, B

    2009-12-01

    This pilot study was designed to assess the incidence of high-level volleyball practice on muscle strength production and muscle activation during internal and external shoulder rotations. Seven professional and seven French amateur league volleyball players performed maximal isometric at three forearm angles, concentric and eccentric isokinetic internal and external shoulder rotations. The torque production and muscle activation levels of PECTORALIS MAJOR and INFRASPINATUS were determined. Few significant differences were found for muscle activation and co-activation between amateur and professional volleyball players during both internal and external rotations. No significant difference in torque production was observed for shoulder internal rotation between professional and amateur volleyball players. Torque production was significantly higher during shoulder external rotation for amateur (46.58+/-2.62 N . m) compared to professional (35.35+/-1.17 N . m) volleyball players relative to isometric contractions, but it was not different during isokinetic efforts. The torque ratios for external/internal rotations were always significantly lower for professional (0.42+/-0.03 pooling isometric and concentric conditions) compared to amateur volleyball players (0.56+/-0.03 pooling isometric and concentric conditions). Those results emphasize that a high level of volleyball practice induces a strong external rotators deficit compared to sports such as swimming, baseball or tennis.

  16. Rotational modulation of the chromospheric activity in the young solar-type star, X-1 Orionis

    NASA Technical Reports Server (NTRS)

    Boesgaard, A. M.; Simon, T.

    1982-01-01

    The IUE satellite was used to observe one of the youngest G stars (GO V) for which Duncan (1981) derives an age of 6 x 10 to the 8th power years from the Li abundance. Rotational modulation was looked for in the emission flux in the chromospheric and transition region lines of this star. Variations in the Ca 11 K-lines profile were studied with the CHF telescope at Mauna Kea. Results show that the same modulation of the emission flux of Ca 11 due to stellar rotation is present in the transition region feature of C IV and probably of He II. For other UV lines the modulation is not apparent, due to a more complex surface distribution of the active areas or supergranulation network, or a shorter lifetime of the conditions which give rise to these features, or to the uncertainities in the measured line strengths. The Mg II emission flux is constant to within + or - 3.4% implying a rather uniform distribution of Mg II emission areas. The Ca II emission not only shows a measurable variation in intensity but also variations in detailed line profile shape when observed at high resolution.

  17. RoboPol: optical polarization-plane rotations and flaring activity in blazars

    NASA Astrophysics Data System (ADS)

    Blinov, D.; Pavlidou, V.; Papadakis, I. E.; Hovatta, T.; Pearson, T. J.; Liodakis, I.; Panopoulou, G. V.; Angelakis, E.; Baloković, M.; Das, H.; Khodade, P.; Kiehlmann, S.; King, O. G.; Kus, A.; Kylafis, N.; Mahabal, A.; Marecki, A.; Modi, D.; Myserlis, I.; Paleologou, E.; Papamastorakis, I.; Pazderska, B.; Pazderski, E.; Rajarshi, C.; Ramaprakash, A.; Readhead, A. C. S.; Reig, P.; Tassis, K.; Zensus, J. A.

    2016-04-01

    We present measurements of rotations of the optical polarization of blazars during the second year of operation of RoboPol, a monitoring programme of an unbiased sample of gamma-ray bright blazars specially designed for effective detection of such events, and we analyse the large set of rotation events discovered in two years of observation. We investigate patterns of variability in the polarization parameters and total flux density during the rotation events and compare them to the behaviour in a non-rotating state. We have searched for possible correlations between average parameters of the polarization-plane rotations and average parameters of polarization, with the following results: (1) there is no statistical association of the rotations with contemporaneous optical flares; (2) the average fractional polarization during the rotations tends to be lower than that in a non-rotating state; (3) the average fractional polarization during rotations is correlated with the rotation rate of the polarization plane in the jet rest frame; (4) it is likely that distributions of amplitudes and durations of the rotations have physical upper bounds, so arbitrarily long rotations are not realized in nature.

  18. The use of external transducers for estimating bone strain at the distal tibia during impact activity.

    PubMed

    Edwards, W Brent; Ward, Erin D; Meardon, Stacey A; Derrick, Timothy R

    2009-05-01

    Noninvasive methods for monitoring the in vivo loading environment of human bone are needed to determine osteogenic loading patterns that reduce the potential for bone injury. The purpose of this study was to determine whether the vertical ground reaction impact force (impact force) and leg acceleration could be used to estimate internal bone strain at the distal tibia during impact activity. Impact loading was delivered to the heels of human-cadaveric lower extremities. The effects of impact mass and contact velocity on peak bone strain, impact force, leg acceleration, and computed impact force (leg acceleration *impact mass) were investigated. Regression analysis was used to predict bone strain from six different models. Apart from leg acceleration, all variables responded to impact loading similarly. Increasing impact mass resulted in increased bone strain, impact force, and computed impact force, but decreased leg acceleration. The best models for bone strain prediction included impact force and tibial cross-sectional area (R(2)=0.94), computed impact force and tibial cross-sectional area (R(2)=0.84), and leg acceleration and tibial cross-sectional area (R(2)=0.73). Results demonstrate that when attempting to estimate bone strain from external transducers some measure of bone strength must be considered. Although it is not recommended that the prediction equations developed in this study be used to predict bone strain in vivo, the strong relationship between bone strain, impact force, and computed impact force suggested that force platforms and leg accelerometers can be used for a surrogate measure of bone strain.

  19. Ion activities in the lateral intercellular spaces of gallbladder epithelium transporting at low external osmolarities.

    PubMed

    Zeuthen, T

    1983-01-01

    The ion activities in the lateral spaces of the unilateral preparation of the gallbladder of Rana catesbiana were measured by double-barrelled ion-selective microelectrodes. The bladders were bathed in a saline solution with a low osmolarity (62 mOsm) containing, in mM: 27 Na+, 27 Cl-, 2 K+, 1 Ca++, 4 HCO3-. Working at reduced osmolarities had the advantage of an increased volume transport and of widened intercellular spaces. The reference barrel recorded an electrical potential of +2.7 mV in the spaces; they contained a solution similar to the external solution. The electrodes recorded a Na+ concentration of 27 mM, a K+ concentration of 1.7 mM, a Ca++ concentration of 0.69 mM and a Cl- concentration of 28.5 mM. In the spaces there was a lower resistance between the tip of the electrode and the serosal bath than that recorded with the tip in the lumen, and injection of fluorescent dye (11 A diameter) via the electrodes did not stain the cells. The concentrations in the secretion were similar to those in the spaces. The intracellular compartment had an apparent K+ concentration of 95 mM, and the concentrations of Na+ and Cl- were both about 5 mM. These data indicate that when the gallbladder is bathed with hypotonic solutions and is transporting fluid at approximately three or four times the normal rate, there are no significant osmotic gradients between the lumen and the lateral spaces. It is suggested that transcellular transport of water is implemented by a combination of high osmotic permeabilities across both mucosal and serosal cell membranes and low reflection coefficients (for K+ salts) at the serosal cell membranes. PMID:6606049

  20. Arylsulphatase activity and sulphate content in relation to crop rotation and fertilization of soil

    NASA Astrophysics Data System (ADS)

    Siwik-Ziomek, Anetta; Lemanowicz, Joanna; Koper, Jan

    2016-07-01

    The aim of the study was to investigate the effect of varying rates of FYM (0, 20, 40, 60 Mg ha-1) and nitrogen N0, N1, N2, and N3 on the content of sulphate sulphur (VI) and the activity of arylsulphatase, which participates in the transformations of this element in Haplic Luvisol. The study report is based on a long-term field experiment with two different crop rotations: A - recognized as exhausting the humus from soil and B - recognized as enriching the soil with humus. During the cultivation of the plants, the soil was sampled four times from corn and a red clover cultivar and grass. The FYM fertilization rate for which the highest arylsulphatase activity and the content of sulphates were identified was 60 Mg ha-1. An inhibitory effect of high rates (90 and 135 kg N ha-1) of ammonium nitrate on the arylsulphatase activity was also observed. A significant correlation between the content of carbon, nitrogen, and sulphates and the arylsulphatase activity was recorded. The investigation on the effect of combined application of farmyard manure and mineral nitrogen fertilization on the activity of arylsulphatase participating in the sulphur cycling was launched to examine the problem in detail.

  1. Generation of picosecond pulses and frequency combs in actively mode locked external ring cavity quantum cascade lasers

    SciTech Connect

    Wójcik, Aleksander K.; Belyanin, Alexey; Malara, Pietro; Blanchard, Romain; Mansuripur, Tobias S.; Capasso, Federico

    2013-12-02

    We propose a robust and reliable method of active mode locking of mid-infrared quantum cascade lasers and develop its theoretical description. Its key element is the use of an external ring cavity, which circumvents fundamental issues undermining the stability of mode locking in quantum cascade lasers. We show that active mode locking can give rise to the generation of picosecond pulses and phase-locked frequency combs containing thousands of the ring cavity modes.

  2. Effect of an 8-week practice of externally triggered speech on basal ganglia activity of stuttering and fluent speakers.

    PubMed

    Toyomura, Akira; Fujii, Tetsunoshin; Kuriki, Shinya

    2015-04-01

    The neural mechanisms underlying stuttering are not well understood. It is known that stuttering appears when persons who stutter speak in a self-paced manner, but speech fluency is temporarily increased when they speak in unison with external trigger such as a metronome. This phenomenon is very similar to the behavioral improvement by external pacing in patients with Parkinson's disease. Recent imaging studies have also suggested that the basal ganglia are involved in the etiology of stuttering. In addition, previous studies have shown that the basal ganglia are involved in self-paced movement. Then, the present study focused on the basal ganglia and explored whether long-term speech-practice using external triggers can induce modification of the basal ganglia activity of stuttering speakers. Our study of functional magnetic resonance imaging revealed that stuttering speakers possessed significantly lower activity in the basal ganglia than fluent speakers before practice, especially when their speech was self-paced. After an 8-week speech practice of externally triggered speech using a metronome, the significant difference in activity between the two groups disappeared. The cerebellar vermis of stuttering speakers showed significantly decreased activity during the self-paced speech in the second compared to the first experiment. The speech fluency and naturalness of the stuttering speakers were also improved. These results suggest that stuttering is associated with defective motor control during self-paced speech, and that the basal ganglia and the cerebellum are involved in an improvement of speech fluency of stuttering by the use of external trigger.

  3. The host stars of Kepler's habitable exoplanets: superflares, rotation and activity

    NASA Astrophysics Data System (ADS)

    Armstrong, D. J.; Pugh, C. E.; Broomhall, A.-M.; Brown, D. J. A.; Lund, M. N.; Osborn, H. P.; Pollacco, D. L.

    2016-01-01

    We embark on a detailed study of the light curves of Kepler's most Earth-like exoplanet host stars using the full length of Kepler data. We derive rotation periods, photometric activity indices, flaring energies, mass-loss rates, gyrochronological ages, X-ray luminosities and consider implications for the planetary magnetospheres and habitability. Furthermore, we present the detection of superflares in the light curve of Kepler-438, the exoplanet with the highest Earth Similarity Index to date. Kepler-438b orbits at a distance of 0.166 au to its host star, and hence may be susceptible to atmospheric stripping. Our sample is taken from the Habitable Exoplanet Catalogue, and consists of the stars Kepler-22, Kepler-61, Kepler-62, Kepler-174, Kepler-186, Kepler-283, Kepler-296, Kepler-298, Kepler-438, Kepler-440, Kepler-442, Kepler-443 and KOI-4427, between them hosting 15 of the most habitable transiting planets known to date from Kepler.

  4. Time-series Doppler imaging of the red giant HD 208472. Active longitudes and differential rotation

    NASA Astrophysics Data System (ADS)

    Özdarcan, O.; Carroll, T. A.; Künstler, A.; Strassmeier, K. G.; Evren, S.; Weber, M.; Granzer, T.

    2016-10-01

    Context. HD 208472 is among the most active RS CVn binaries with cool starspots. Decade-long photometry has shown that the spots seem to change their longitudinal appearance with a period of about six years, coherent with brightness variations. Aims: Our aim is to spatially resolve the stellar surface of HD 208472 and relate the photometric results to the true longitudinal and latitudinal spot appearance. Furthermore, we investigate the surface differential rotation pattern of the star. Methods: We employed three years of high-resolution spectroscopic data with a high signal-to-noise ratio (S/N) from the STELLA robotic observatory and determined new and more precise stellar physical parameters. Precalculated synthetic spectra were fit to each of these spectra, and we provide new spot-corrected orbital elements. A sample of 34 absorption lines per spectrum was used to calculate mean line profiles with a S/N of several hundred. A total of 13 temperature Doppler images were reconstructed from these line profiles with the inversion code iMap. Differential rotation was investigated by cross-correlating successive Doppler images in each observing season. Results: Spots on HD 208472 are distributed preferably at high latitudes and less frequently around mid-to-low latitudes. No polar-cap like structure is seen at any epoch. We observed a flip-flop event between 2009 and 2010, manifested as a flip of the spot activity from phase 0.0 to phase 0.5, while the overall brightness of the star continued to increase and reached an all-time maximum in 2014. Cross-correlation of successive Doppler images suggests a solar-like differential rotation that is ≈15 times weaker than that of the Sun. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC, and the Potsdam Automatic Photoelectric Telescopes (APT) in Arizona, jointly operated by AIP and Fairborn Observatory.Radial velocity measurements are only available at the

  5. Sub-soil microbial activity under rotational cotton crops in Australia

    NASA Astrophysics Data System (ADS)

    Polain, Katherine; Knox, Oliver; Wilson, Brian; Pereg, Lily

    2016-04-01

    Soil microbial communities contribute significantly to soil organic matter formation, stabilisation and destabilisation, through nutrient cycling and biodegradation. The majority of soil microbial research examines the processes occurring in the top 0 cm to 30 cm of the soil, where organic nutrients are easily accessible. In soils such as Vertosols, the high clay content causes swelling and cracking. When soil cracking is coupled with rain or an irrigation event, a flush of organic nutrients can move down the soil profile, becoming available for subsoil microbial community use and potentially making a significant contribution to nutrient cycling and biodegradation in soils. At present, the mechanisms and rates of soil nutrient turnover (such as carbon and nitrogen) at depth under cotton rotations are mostly speculative and the process-response relationships remain unclear, although they are undoubtedly underpinned by microbial activity. Our research aims to determine the contribution and role of soil microbiota to the accumulation, cycling and mineralisation of carbon and nitrogen through the whole root profile under continuous cotton (Gossypium hirsutum) and cotton-maize rotations in regional New South Wales, Australia. Through seasonal work, we have established both baseline and potential microbial activity rates from 0 cm to 100 cm down the Vertosol profile, using respiration and colourimetric methods. Further whole soil profile analyses will include determination of microbial biomass and isotopic carbon signatures using phospholipid fatty acid (PLFA) methodology, identification of microbial communities (sequencing) and novel experiments to investigate potential rates of nitrogen mineralisation and quantification of associated genes. Our preliminary observations and the hypotheses tested in this three-year study will be presented.

  6. Modeling the Effect of External Carbon Source Addition under Different Electron Acceptor Conditions in Biological Nutrient Removal Activated Sludge Systems.

    PubMed

    Hu, Xiang; Wisniewski, Kamil; Czerwionka, Krzysztof; Zhou, Qi; Xie, Li; Makinia, Jacek

    2016-02-16

    The aim of this study was to expand the International Water Association Activated Sludge Model No. 2d (ASM2d) to predict the aerobic/anoxic behavior of polyphosphate accumulating organisms (PAOs) and "ordinary" heterotrophs in the presence of different external carbon sources and electron acceptors. The following new aspects were considered: (1) a new type of the readily biodegradable substrate, not available for the anaerobic activity of PAOs, (2) nitrite as an electron acceptor, and (3) acclimation of "ordinary" heterotrophs to the new external substrate via enzyme synthesis. The expanded model incorporated 30 new or modified process rate equations. The model was evaluated against data from several, especially designed laboratory experiments which focused on the combined effects of different types of external carbon sources (acetate, ethanol and fusel oil) and electron acceptors (dissolved oxygen, nitrate and nitrite) on the behavior of PAOs and "ordinary" heterotrophs. With the proposed expansions, it was possible to improve some deficiencies of the ASM2d in predicting the behavior of biological nutrient removal (BNR) systems with the addition of external carbon sources, including the effect of acclimation to the new carbon source. PMID:26783836

  7. Modeling the Effect of External Carbon Source Addition under Different Electron Acceptor Conditions in Biological Nutrient Removal Activated Sludge Systems.

    PubMed

    Hu, Xiang; Wisniewski, Kamil; Czerwionka, Krzysztof; Zhou, Qi; Xie, Li; Makinia, Jacek

    2016-02-16

    The aim of this study was to expand the International Water Association Activated Sludge Model No. 2d (ASM2d) to predict the aerobic/anoxic behavior of polyphosphate accumulating organisms (PAOs) and "ordinary" heterotrophs in the presence of different external carbon sources and electron acceptors. The following new aspects were considered: (1) a new type of the readily biodegradable substrate, not available for the anaerobic activity of PAOs, (2) nitrite as an electron acceptor, and (3) acclimation of "ordinary" heterotrophs to the new external substrate via enzyme synthesis. The expanded model incorporated 30 new or modified process rate equations. The model was evaluated against data from several, especially designed laboratory experiments which focused on the combined effects of different types of external carbon sources (acetate, ethanol and fusel oil) and electron acceptors (dissolved oxygen, nitrate and nitrite) on the behavior of PAOs and "ordinary" heterotrophs. With the proposed expansions, it was possible to improve some deficiencies of the ASM2d in predicting the behavior of biological nutrient removal (BNR) systems with the addition of external carbon sources, including the effect of acclimation to the new carbon source.

  8. On the coronae of rapidly rotating stars. I - The relation between rotation and coronal activity in RS CVn systems

    NASA Technical Reports Server (NTRS)

    Walter, F. M.; Bowyer, S.

    1981-01-01

    Soft X-ray observations are presented of a nearly complete sample of RS Canum Venaticorum systems taken with the Einstein X-ray Observatory. It is shown that the quiescent coronal activity, as measured by the ratio of the X-ray to bolometric flux, is directly proportional to the angular velocity of the star with the active chromosphere in these systems. This relation is found to hold over two decades in angular velocity. It is also found that the stellar surface gravity has no obvious influence on the ratio of the X-ray luminosity to the bolometric luminosity over two decades in surface gravity. It is pointed out that the linear relation between the ratio of the X-ray luminosity to the bolometric luminosity on the one hand, and the angular velocity, on the other, holds important implications for dynamo theories of the generation of stellar magnetic fields.

  9. External current application in a bidomain model of active neural tissue.

    PubMed

    Keim, Steven F; Fu, Fanrui; Sadleir, Rosalind J

    2015-08-01

    The formal treatment of tissue as two coupled continua is referred to as a bidomain model. Bidomain models have recently been used to describe the properties of neural tissue and nerve fiber bundles [1, 2]. By adapting the Hodgkin Huxley equations in COMSOL Multiphysics, we have investigated the propagation of an action potential through neural tissue by external current stimulation. PMID:26736753

  10. Dysregulated Coherence of Subjective and Cardiac Emotional Activation in Adolescents with Internalizing and Externalizing Problems

    ERIC Educational Resources Information Center

    Hastings, Paul D.; Nuselovici, Jacob N.; Klimes-Dougan, Bonnie; Kendziora, Kimberly T.; Usher, Barbara A.; Ho, Moon-Ho R.; Zahn-Waxler, Carolyn

    2009-01-01

    Background: Effective emotion regulation should be reflected in greater coherence between physiological and subjective aspects of emotional responses. Method: Youths with normative to clinical levels of internalizing problems (IP) and externalizing problems (EP) watched emotionally evocative film-clips while having heart rate (HR) recorded, and…

  11. F{sub o}F{sub 1}-ATPase activity regulated by external links on {beta} subunits

    SciTech Connect

    Cheng, Jie; Zhang, Xiao-ai; Shu, Yao-Gen; Yue, Jia-Chang

    2010-01-01

    F{sub o}F{sub 1}-ATPase activity is regulated by external links on {beta} subunits with different molecular weight. It is inhibited when anti-{beta} subunit antibody, streptavidin and H9 antibody link on the {beta} subunits successively, but is activated when virus was binded. Western blotting indicated that the employed anti-{beta} antibody target was on the non-catalytic site of the {beta} subunit. Furthermore, an ESR study of spin-labeled ATP (SL-ATP) showed that the affinity of ATP to the holoenzyme increases with increasing external links on the {beta} subunits. This simple regulation method may have great potential in the design of rapid, free labeled, sensitive and selective biosensors.

  12. Active Brownian motion of emulsion droplets: Coarsening dynamics at the interface and rotational diffusion.

    PubMed

    Schmitt, M; Stark, H

    2016-08-01

    A micron-sized droplet of bromine water immersed in a surfactant-laden oil phase can swim (S. Thutupalli, R. Seemann, S. Herminghaus, New J. Phys. 13 073021 (2011). The bromine reacts with the surfactant at the droplet interface and generates a surfactant mixture. It can spontaneously phase-separate due to solutocapillary Marangoni flow, which propels the droplet. We model the system by a diffusion-advection-reaction equation for the mixture order parameter at the interface including thermal noise and couple it to fluid flow. Going beyond previous work, we illustrate the coarsening dynamics of the surfactant mixture towards phase separation in the axisymmetric swimming state. Coarsening proceeds in two steps: an initially slow growth of domain size followed by a nearly ballistic regime. On larger time scales thermal fluctuations in the local surfactant composition initiates random changes in the swimming direction and the droplet performs a persistent random walk, as observed in experiments. Numerical solutions show that the rotational correlation time scales with the square of the inverse noise strength. We confirm this scaling by a perturbation theory for the fluctuations in the mixture order parameter and thereby identify the active emulsion droplet as an active Brownian particle. PMID:27562831

  13. Active Brownian motion of emulsion droplets: Coarsening dynamics at the interface and rotational diffusion.

    PubMed

    Schmitt, M; Stark, H

    2016-08-01

    A micron-sized droplet of bromine water immersed in a surfactant-laden oil phase can swim (S. Thutupalli, R. Seemann, S. Herminghaus, New J. Phys. 13 073021 (2011). The bromine reacts with the surfactant at the droplet interface and generates a surfactant mixture. It can spontaneously phase-separate due to solutocapillary Marangoni flow, which propels the droplet. We model the system by a diffusion-advection-reaction equation for the mixture order parameter at the interface including thermal noise and couple it to fluid flow. Going beyond previous work, we illustrate the coarsening dynamics of the surfactant mixture towards phase separation in the axisymmetric swimming state. Coarsening proceeds in two steps: an initially slow growth of domain size followed by a nearly ballistic regime. On larger time scales thermal fluctuations in the local surfactant composition initiates random changes in the swimming direction and the droplet performs a persistent random walk, as observed in experiments. Numerical solutions show that the rotational correlation time scales with the square of the inverse noise strength. We confirm this scaling by a perturbation theory for the fluctuations in the mixture order parameter and thereby identify the active emulsion droplet as an active Brownian particle.

  14. Intercostal muscles are used during rotation of the thorax in humans.

    PubMed

    Whitelaw, W A; Ford, G T; Rimmer, K P; De Troyer, A

    1992-05-01

    To test the idea that the lateral intercostal muscles may be more suited to aid in rotational than respiratory movements of the thorax, we inserted bipolar fine-wire electrodes in external and internal intercostal muscles in the right midaxillary line in nine sitting subjects and examined the pattern of contraction of these muscles during voluntary axial rotations of the thorax (30-35 degrees), resting breathing, and CO2-induced hyperpnea. The right external intercostal muscles were strongly recruited in rotations to the left but were not active in rotations to the right. In contrast, the right internal intercostal muscles were active in rotations to the right but not in rotations to the left. Rotations completed in 1 or 2 s were associated with an early burst of electromyographic activity, followed by a low plateau that persisted while the rotation was held. Rotations made very gradually over 5-10 s were associated with gradually rising electromyographic activity. The amplitude of activity recorded during 30-35 degrees rotations was equivalent to that measured when minute ventilation was increased by CO2 to 50 l/min. We conclude that the lateral intercostal muscles have a major role in producing axial rotations of the thorax. PMID:1601803

  15. Ruthenium-based olefin metathesis catalysts bearing pH-responsive ligands: External control of catalyst solubility and activity

    NASA Astrophysics Data System (ADS)

    Balof, Shawna Lynn

    2011-12-01

    Sixteen novel, Ru-based olefin metathesis catalysts bearing pH responsive ligands were synthesized. The pH-responsive groups employed with these catalysts included dimethylamino (NMe2) modified NHC ligands as well as N-donor dimethylaminopyridine (DMAP) and 3-(o-pyridyl)propylidene ligands. These pH-responsive ligands provided the means by which the solubility and/or activity profiles of the catalysts produced could be controlled via acid addition. The main goal of this dissertation was to design catalyst systems capable of performing ring opening metathesis (ROMP) and ring closing metathesis (RCM) reactions in both organic and aqueous media. In an effort to quickly gain access to new catalyst structures, a template synthesis for functionalized NHC ligand precursors was designed, in addition to other strategies, to obtain ligand precursors with ancillary NMe2 groups. Kinetic studies for the catalysts produced from these precursors showed external control of catalyst solubility was afforded via protonation of the NMe2 groups of their NHC ligands. Additionally, this protonation afforded external control of catalyst propagation rates for several catalysts. This is the first known independent external control for the propagation rates of ROMP catalysts. The incorporation of pH-responsive N-donor ligands into catalyst structures also provided the means for the external control of metathesis activity, as the protonation of these ligands resulted in an increased initiation rate based on their fast and irreversible dissociation from the metal center. The enhanced external control makes these catalysts applicable to a wide range of applications, some of which have been explored by us and/or through collaboration. Three of the catalysts designed showed remarkable metathesis activity in aqueous media. These catalysts displayed comparable RCM activity in aqueous media to a class of water-soluble catalysts reported by Grubbs et al., considered to be the most active catalyst for

  16. Effect of Modeling-Based Activities Developed Using Virtual Environments and Concrete Objects on Spatial Thinking and Mental Rotation Skills

    ERIC Educational Resources Information Center

    Yurt, Eyup; Sunbul, Ali Murat

    2012-01-01

    In this study, the effect of modeling based activities using virtual environments and concrete objects on spatial thinking and mental rotation skills was investigated. The study was designed as a pretest-posttest model with a control group, which is one of the experimental research models. The study was carried out on sixth grade students…

  17. Integrating Structured Learning and Scholarly Activities into Clerkship Rotations: A Win–Win for Students and Preceptors

    PubMed Central

    Miller, Stephannie; Fulton, Judith; Mostow, Eliot

    2014-01-01

    Objective: To merge scholarly activity into the curriculum developed for medical students electing a rotation in wound care and/or dermatology. Approach: The authors adapted the unique wound care curriculum developed for medical student rotators and residents to incorporate structured scholarly projects, opportunities for mentorship, and feedback for continued improvement. Results: Benefits have been observed to both students and to the clinic, as reflected by online survey results, increased productivity in the form of posters and manuscripts, and opportunities for professional networking. Discussion: Rotations and clerkships can be transformed from haphazard, bystander observational experiences to active participation that enhances comprehension and retention, while also providing benefits to preceptors. Innovation: Integration between research, education, and clinical activities in a structured way can provide opportunity for enhanced learning experiences and promote the concept of evidence-based practice. Conclusion: With observed benefits to students, researchers, and staff in this clinical setting, other clerkship rotation settings should consider an integrated and structured approach to learning, which includes scholarly activities. Further rigorous program evaluation is necessary to further quantify preliminary positive feedback regarding this approach. PMID:24804160

  18. Rotation and magnetic activity of the Hertzsprung-gap giant 31 Comae

    NASA Astrophysics Data System (ADS)

    Strassmeier, K. G.; Granzer, T.; Kopf, M.; Weber, M.; Küker, M.; Reegen, P.; Rice, J. B.; Matthews, J. M.; Kuschnig, R.; Rowe, J. F.; Guenther, D. B.; Moffat, A. F. J.; Rucinski, S. M.; Sasselov, D.; Weiss, W. W.

    2010-09-01

    Context. The single rapidly-rotating G0 giant 31 Comae has been a puzzle because of the absence of photometric variability despite its strong chromospheric and coronal emissions. As a Hertzsprung-gap giant, it is expected to be at the stage of rearranging its moment of inertia, hence likely also its dynamo action, which could possibly be linked with its missing photospheric activity. Aims: Our aim is to detect photospheric activity, obtain the rotation period, and use it for a first Doppler image of the star's surface. Its morphology could be related to the evolutionary status. Methods: We carried out high-precision, white-light photometry with the MOST satellite, ground-based Strömgren photometry with automated telescopes, and high-resolution optical echelle spectroscopy with the new STELLA robotic facility. Results: The MOST data reveal, for the first time, light variations with a full amplitude of 5 mmag and an average photometric period of 6.80 ± 0.06 days. Radial-velocity variations with a full amplitude of 270 m s-1 and a period of 6.76 ± 0.02 days were detected from our STELLA spectra, which we also interpret as due to stellar rotation. The two-year constancy of the average radial velocity of +0.10 ± 0.33 km s-1 confirms the star's single status, as well as the membership in the cluster Melotte 111. A spectrum synthesis gives Teff = 5660 ± 42 K, log g = 3.51 ± 0.09, and [Fe/H] = -0.15 ± 0.03, which together with the revised Hipparcos distance, suggests a mass of 2.6 ± 0.1 M_⊙ and an age of ≈540 Myr. The surface lithium abundance is measured to be nearly primordial. A detection of a strong He i absorption line indicates nonradiative heating processes in the atmosphere. Our Doppler images show a large, asymmetric polar spot, cooler than Teff by ≈1600 K, and several small low-to-mid latitude features that are warmer by ≈300-400 K and are possibly of chromospheric origin. We computed the convective turnover time for 31 Com as a function of depth

  19. Long-range active retroreflector to measure the rotational orientation in conjunction with a laser tracker

    NASA Astrophysics Data System (ADS)

    Hofherr, O.; Wachten, Christian; Müller, C.; Reinecke, H.

    2014-11-01

    High precision optical non-contact position measurement is a key technology in modern engineering. Laser trackers (LT) accurately determine x-y-z coordinates of passive retroreflectors. Next-generation systems answer the need to measure an object`s rotational orientation (pitch, yaw, roll). So far, these devices are based either on photogrammetry or on enhanced retroreflectors. Here we present a new method to measure all six degrees of freedom in conjunction with a LT. The basic principle is to analyze the orientation to the LT's beam path by coupling-out laser radiation. The optical design is inspired by a cat's eye retroreflector equipped with an integrated beam splitter layer. The optical spherical aberration is compensated, which reduces the divergence angle for the reflected beam by one order of magnitude compared to an uncompensated standard system of the same size. The wave front distortion is reduced to less than 0.1 λ @ 633 nm for beam diameters up to 8 mm. Our active retroreflector is suitable for long-range measurements for a distance > 10 m.

  20. A dynamo model of magnetic activity in solar-like stars with different rotational velocities

    SciTech Connect

    Karak, Bidya Binay; Choudhuri, Arnab Rai; Kitchatinov, Leonid L.

    2014-08-10

    We attempt to provide a quantitative theoretical explanation for the observations that Ca II H/K emission and X-ray emission from solar-like stars increase with decreasing Rossby number (i.e., with faster rotation). Assuming that these emissions are caused by magnetic cycles similar to the sunspot cycle, we construct flux transport dynamo models of 1 M{sub ☉} stars rotating with different rotation periods. We first compute the differential rotation and the meridional circulation inside these stars from a mean-field hydrodynamics model. Then these are substituted in our dynamo code to produce periodic solutions. We find that the dimensionless amplitude f{sub m} of the toroidal flux through the star increases with decreasing rotation period. The observational data can be matched if we assume the emissions to go as the power 3-4 of f{sub m}. Assuming that the Babcock-Leighton mechanism saturates with increasing rotation, we can provide an explanation for the observed saturation of emission at low Rossby numbers. The main failure of our model is that it predicts an increase of the magnetic cycle period with increasing rotation rate, which is the opposite of what is found observationally. Much of our calculations are based on the assumption that the magnetic buoyancy makes the magnetic flux tubes rise radially from the bottom of the convection zone. Taking into account the fact that the Coriolis force diverts the magnetic flux tubes to rise parallel to the rotation axis in rapidly rotating stars, the results do not change qualitatively.

  1. Toroidal Rotation in RF Heated JET Plasmas

    SciTech Connect

    Eriksson, L.-G.; Nave, F.; Zastrow, K.-D.

    2007-09-28

    Experiments have been carried out on JET aimed at studying rotation in RF heated plasmas with low external momentum input. Both plasmas with Ion Cyclotron Resonance Frequency (ICRF) heating and Lower Hybrid Current Drive (LHCD) have been investigated. The rotation profiles are measured by Charge Exchange recombination spectroscopy, using short diagnostic Neutral Beam Injection (NBI) pulses. Moreover, the temporal evolution of the central rotation could in some cases be deduced from MHD activity. While most of the measurements were focussed on ICRF heating, the profiles measured in plasmas with LHCD are interesting since they are the first reported from JET in such plasmas. In particular, they allowed for studies of rotation in RF heated plasmas with q>1. The experimental results are presented together with an analysis of the torque from ICRF heated fast ions.

  2. Magnetism and rotation in relativistic field theory

    NASA Astrophysics Data System (ADS)

    Mameda, Kazuya; Yamamoto, Arata

    2016-09-01

    We investigate the analogy between magnetism and rotation in relativistic theory. In nonrelativistic theory, the exact correspondence between magnetism and rotation is established in the presence of an external trapping potential. Based on this, we analyze relativistic rotation under external trapping potentials. A Landau-like quantization is obtained by considering an energy-dependent potential.

  3. Thrombus imaging in a primate model with antibodies specific for an external membrane protein of activated platelets

    SciTech Connect

    Palabrica, T.M.; Furie, B.C.; Konstam, M.A.; Aronovitz, M.J.; Connolly, R.; Brockway, B.A.; Ramberg, K.L.; Furie, B.

    1989-02-01

    The activated platelet is a potential target for the localization of thrombi in vivo since, after stimulation and secretion of granule contents, activated platelets are concentrated at sites of blood clot formation. In this study, we used antibodies specific for a membrane protein of activated platelets to detect experimental thrombi in an animal model. PADGEM (platelet activation-dependent granule-external membrane protein), a platelet alpha-granule membrane protein, is translocated to the plasma membrane during platelet activation and granule secretion. Since PADGEM is internal in unstimulated platelets, polyclonal anti-PADGEM and monoclonal KC4 antibodies do not bind to circulating resting platelets but do interact with activated platelets. Dacron graft material incubated with radiolabeled KC4 or anti-PADGEM antibodies in the presence of thrombin-activated platelet-rich plasma bound most of the antibody. Imaging experiments with 123I-labeled anti-PADGEM in baboons with an external arterial-venous Dacron shunt revealed rapid uptake in the thrombus induced by the Dacron graft; control experiments with 123I-labeled nonimmune IgG exhibited minimal uptake. Deep venous thrombi, formed by using percutaneous balloon catheters to stop blood flow in the femoral vein of baboons, were visualized with 123I-labeled anti-PADGEM. Thrombi were discernible against blood pool background activity without subtraction techniques within 1 hr. No target enhancement was seen with 123I-labeled nonimmune IgG. 123I-labeled anti-PADGEM cleared the blood pool with an initial half-disappearance time of 6 min and did not interfere with hemostasis. These results indicate that radioimmunoscintigraphy with anti-PADGEM antibodies can visualize thrombi in baboon models and is a promising technique for clinical thrombus detection in humans.

  4. Cells as Active Particles in Asymmetric Potentials: Motility under External Gradients

    PubMed Central

    Comelles, Jordi; Caballero, David; Voituriez, Raphaël; Hortigüela, Verónica; Wollrab, Viktoria; Godeau, Amélie Luise; Samitier, Josep; Martínez, Elena; Riveline, Daniel

    2014-01-01

    Cell migration is a crucial event during development and in disease. Mechanical constraints and chemical gradients can contribute to the establishment of cell direction, but their respective roles remain poorly understood. Using a microfabricated topographical ratchet, we show that the nucleus dictates the direction of cell movement through mechanical guidance by its environment. We demonstrate that this direction can be tuned by combining the topographical ratchet with a biochemical gradient of fibronectin adhesion. We report competition and cooperation between the two external cues. We also quantitatively compare the measurements associated with the trajectory of a model that treats cells as fluctuating particles trapped in a periodic asymmetric potential. We show that the cell nucleus contributes to the strength of the trap, whereas cell protrusions guided by the adhesive gradients add a constant tunable bias to the direction of cell motion. PMID:25296303

  5. External corrosion of line pipe -- A summary of research activities performed since 1983

    SciTech Connect

    Jack, T.R.; Wilmott, M.J.; Sutherby, R.L.; Worthington, R.G.

    1995-11-01

    External corrosion is a major threat to the integrity of gas transmission systems. This paper reviews corrosion and environmental cracking problems and their control based on more than twelve years of field and laboratory research work performed by a major Canadian gas transmission company. To protect against corrosion the company uses a dual system consisting of protective coatings and cathodic protection. Either of these systems operating properly can provide the protection necessary to prevent leaks and ruptures in line pipe. In some situations however coatings can fail in such a way as to shield a corrosion cell on the pipe surface under degraded coating from cathodic protection. Where the protective systems are thwarted, a variety of corrosion and cracking scenarios can lead to leaks and ruptures. These scenarios will be identified and assessed in terms of where they occur as well as their frequency and seriousness.

  6. Distribution of electrical activation to the external intercostal muscles during high frequency spinal cord stimulation in dogs.

    PubMed

    DiMarco, Anthony F; Kowalski, Krzysztof E

    2011-03-15

    In contrast to previous methods of electrical stimulation of the inspiratory muscles, high frequency spinal cord stimulation (HF-SCS) results in more physiological activation of these muscles. The spatial distribution of activation to the external intercostal muscles by this method is unknown. In anaesthetized dogs, multiunit and single motor unit (SMU) EMG activity was monitored in the dorsal portion of the 3rd, 5th and 7th interspaces and ventral portion of the 3rd interspace during spontaneous breathing and HF-SCS following C2 spinal section. Stimulus amplitude during HF-SCS was adjusted such that inspired volumes matched spontaneous breathing (Protocol 1). During HF-SCS, mean peak SMU firing frequency was highest in the 3rd interspace (dorsal) (18.8 ± 0.3 Hz) and significantly lower in the 3rd interspace (ventral) (12.2 ± 0.2 Hz) and 5th interspace (dorsal) (15.3 ± 0.3 Hz) (P <0.05 for each comparison). Similar rostrocaudal and dorsoventral gradients of activity were observed during spontaneous breathing prior to C2 section. No significant activity was observed in the 7th interspace during either spontaneous breathing or HF-SCS. Since peak discharge frequencies of the SMUs were higher and rib cage movement greater during HF-SCS compared to spontaneous breathing, stimulus amplitude during HF-SCS was adjusted such that rib cage movement matched (Protocol 2). Under these conditions, mean peak SMU frequencies and rostrocaudal and dorsoventral gradients of activity during HF-SCS were not significantly different compared to spontaneous breathing. These results indicate that (a) the topographic pattern of electrical activation of the external intercostal muscles during HF-SCS is similar to that occurring during spontaneous breathing and (b) differential descending synaptic input from supraspinal centres is not a required component of the differential spatial distribution of external intercostal muscle activation. HF-SCS may provide a more physiological method of

  7. Transient epileptiform signaling during neuronal network development: regulation by external stimulation and bimodal GABAergic activity.

    PubMed

    Zemianek, Jill M; Shultz, Abraham M; Lee, Sangmook; Guaraldi, Mary; Yanco, Holly A; Shea, Thomas B

    2013-04-01

    A predominance of excitatory activity, with protracted appearance of inhibitory activity, accompanies cortical neuronal development. It is unclear whether or not inhibitory neuronal activity is solicited exclusively by excitatory neurons or whether the transient excitatory activity displayed by developing GABAergic neurons contributes to an excitatory threshold that fosters their conversion to inhibitory activity. We addressed this possibility by culturing murine embryonic neurons on multi-electrode arrays. A wave of individual 0.2-0.4 mV signals ("spikes") appeared between approx. 20-30 days in culture, then declined. A transient wave of high amplitude (>0.5 mV) epileptiform activity coincided with the developmental decline in spikes. Bursts (clusters of ≥3 low-amplitude spikes within 0.7s prior to returning to baseline) persisted following this decline. Addition of the GABAergic antagonist bicuculline initially had no effect on signaling, consistent with delayed development of GABAergic synapses. This was followed by a period in which bicuculline inhibited overall signaling, confirming that GABAergic neurons initially display excitatory activity in ex vivo networks. Following the transient developmental wave of epileptiform signaling, bicuculline induced a resurgence of epileptiform signaling, indicating that GABAergic neurons at this point displayed inhibitory activity. The appearance of transition after the developmental and decline of epileptiform activity, rather than immediately after the developmental decline in lower-amplitude spikes, suggests that the initial excitatory activity of GABAergic neurons contributes to their transition into inhibitory neurons, and that inhibitory GABAergic activity is essential for network development. Prior studies indicate that a minority (25%) of neurons in these cultures were GABAergic, suggesting that inhibitory neurons regulate multiple excitatory neurons. A similar robust increase in signaling following cessation of

  8. Active correction of the tilt angle of the surface plane with respect to the rotation axis during azimuthal scan

    NASA Astrophysics Data System (ADS)

    Sereno, M.; Lupone, S.; Debiossac, M.; Kalashnyk, N.; Roncin, P.

    2016-09-01

    A procedure to measure the residual tilt angle τ between a flat surface and the azimuthal rotation axis of the sample holder is described. When the incidence angle θ and readout of the azimuthal angle ϕ are controlled by motors, an active compensation mechanism can be implemented to reduce the effect of the tilt angle during azimuthal motion. After this correction, the effective angle of incidence is kept fixed, and only a small residual oscillation of the scattering plane remains.

  9. Validity and reliability of isometric muscle strength measurements of hip abduction and abduction with external hip rotation in a bent-hip position using a handheld dynamometer with a belt

    PubMed Central

    Aramaki, Hidefumi; Katoh, Munenori; Hiiragi, Yukinobu; Kawasaki, Tsubasa; Kurihara, Tomohisa; Ohmi, Yorikatsu

    2016-01-01

    [Purpose] This study aimed to investigate the relatedness, reliability, and validity of isometric muscle strength measurements of hip abduction and abduction with an external hip rotation in a bent-hip position using a handheld dynamometer with a belt. [Subjects and Methods] Twenty healthy young adults, with a mean age of 21.5 ± 0.6 years were included. Isometric hip muscle strength in the subjects’ right legs was measured under two posture positions using two devices: a handheld dynamometer with a belt and an isokinetic dynamometer. Reliability was evaluated using an intra-class correlation coefficient (ICC); relatedness and validity were evaluated using Pearson’s product moment correlation coefficient. Differences in measurements of devices were assessed by two-way ANOVA. [Results] ICC (1, 1) was ≥0.9; significant positive correlations in measurements were found between the two devices under both conditions. No main effect was found between the measurement values. [Conclusion] Our findings revealed that there was relatedness, reliability, and validity of this method for isometric muscle strength measurements using a handheld dynamometer with a belt. PMID:27512280

  10. Neural Activation During Mental Rotation in Complete Androgen Insensitivity Syndrome: The Influence of Sex Hormones and Sex Chromosomes.

    PubMed

    van Hemmen, Judy; Veltman, Dick J; Hoekzema, Elseline; Cohen-Kettenis, Peggy T; Dessens, Arianne B; Bakker, Julie

    2016-03-01

    Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a 46,XY karyotype but a female phenotype due to a complete androgen resistance, enable us to study the separate effects of gonadal hormones versus sex chromosomes on neural sex differences. Therefore, in the present study, we compared 46,XY men (n = 30) and 46,XX women (n = 29) to 46,XY individuals with CAIS (n = 21) on a mental rotation task using functional magnetic resonance imaging. Previously reported sex differences in neural activation during mental rotation were replicated in the control groups, with control men showing more activation in the inferior parietal lobe than control women. Individuals with CAIS showed a female-like neural activation pattern in the parietal lobe, indicating feminization of the brain in CAIS. Furthermore, this first neuroimaging study in individuals with CAIS provides evidence that sex differences in regional brain function during mental rotation are most likely not directly driven by genetic sex, but rather reflect gonadal hormone exposure.

  11. Pausing and activating thread state upon pin assertion by external logic monitoring polling loop exit time condition

    SciTech Connect

    Chen, Dong; Giampapa, Mark; Heidelberger, Philip; Ohmacht, Martin; Satterfield, David L; Steinmacher-Burow, Burkhard; Sugavanam, Krishnan

    2013-05-21

    A system and method for enhancing performance of a computer which includes a computer system including a data storage device. The computer system includes a program stored in the data storage device and steps of the program are executed by a processer. The processor processes instructions from the program. A wait state in the processor waits for receiving specified data. A thread in the processor has a pause state wherein the processor waits for specified data. A pin in the processor initiates a return to an active state from the pause state for the thread. A logic circuit is external to the processor, and the logic circuit is configured to detect a specified condition. The pin initiates a return to the active state of the thread when the specified condition is detected using the logic circuit.

  12. Coarse-grained modeling of vesicle responses to active rotational nanoparticles

    NASA Astrophysics Data System (ADS)

    Zhang, Liuyang; Wang, Xianqiao

    2015-08-01

    In recent years, magnetically-driven-rotating superparamagnetic nanoparticles have been emerging as a valuable component in designing targeted drug delivery carriers and cellular killers via membranes' physical rupture. The lack of an in-depth understanding of how to control the interaction of rotational nanoparticles (RNPs) with vesicles has hindered progress in the development of their relevant biomedical applications. Here we perform dissipative particle dynamics simulations to analyze the rotation frequencies, size, and coating patterns of the RNPs as they interact with the vesicle so as to provide novel designs of drug delivery applications. Results have revealed that the RNPs are capable of triggering local disturbance around the vesicle and therefore promoting the vesicle translocation toward the RNPs. By investigating the translocation time and driving forces required for RNPs to enter inside the vesicle at various rotation frequencies as well as the interaction energy between coated RNPs and the vesicle, we have tuned the coating pattern of the ligands on the surface of RNPs to open a specified channel in the vesicle for promoting drug delivery. Our findings can provide useful guidelines for the molecular design of patterned RNPs for controllable bio/inorganic interfaces and help establish qualitative rules for the organization and optimization of ligands on the surface of the desired drug delivery carriers.

  13. Dependence upon external calcium for contractile activity in two molluscan proboscis muscles.

    PubMed

    Alohan, F I

    1991-01-01

    1. Both the radular sac and odontophore retractor muscles of Buccinum undatum depend upon [Ca]0 to raise the [Ca]i concentration of the contractile system to activation level. 2. The K-induced responses of the muscles depend mainly upon [Ca]0 for activator Ca while the ACh responses depend upon [Ca]0 to raise stored intracellular Ca to activation levels. 3. In the radular sac muscle, it is probable that the inward current is carried by Na+ or is Na(+)-dependent and this current may release [Ca]i for contraction since the muscle became spontaneously active during ACh- and K-contractures in Ca-free seawater containing 2 mM EGTA as a calcium chelator. 4. It is proposed that since calcium antagonists are more inhibitory on ACh responses than on K-contractures, ACh releases the activator calcium for the contractile system through a slow-type Ca channel while high K releases Ca through a fast-type calcium channel in these muscles.

  14. 42 CFR 438.358 - Activities related to external quality review.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Validation of performance improvement projects required by the State to comply with requirements set forth in § 438.240(b)(1) and that were underway during the preceding 12 months. (2) Validation of MCO or PIHP... derived during the preceding 12 months from the following optional activities: (1) Validation of...

  15. Reference activity and the external user: confluence of community needs at a medical school branch library.

    PubMed Central

    Landwirth, T K; Wilson, M L; Dorsch, J

    1988-01-01

    The allocation of reference services between primary and secondary users constantly challenges academic medical libraries. Routine statistics at a medical school branch library suggested that over 40% of its reference transactions involved persons not affiliated with the university. To investigate this finding, a survey of reference activity was conducted using measurement techniques unobtrusive to the user. Fifteen data items were recorded, including user status, type of question, intended use of information requested, status of staff taking request, and staff time spent. Survey results showed that nonaffiliates accounted for 51% of reference activity. Based on this documented data, definitive reference guidelines addressing hours, priority of requests, charges, and staffing patterns can now be developed. Findings will also assist in evaluating the library's regional role, in formulating marketing strategies, and in determining library objectives. PMID:3416093

  16. A new way towards high-efficiency thermally activated delayed fluorescence devices via external heavy-atom effect

    NASA Astrophysics Data System (ADS)

    Zhang, Wenzhi; Jin, Jiangjiang; Huang, Zhi; Zhuang, Shaoqing; Wang, Lei

    2016-07-01

    Thermally activated delayed fluorescence (TADF) mechanism is a significant method that enables the harvesting of both triplet and singlet excitons for emission. However, up to now most efforts have been devoted to dealing with the relation between singlet-triplet splitting (ΔEST) and fluorescence efficiency, while the significance of spin-orbit coupling (SOC) is usually ignored. In this contribution, a new method is developed to realize high-efficiency TADF-based devices through simple device-structure optimizations. By inserting an ultrathin external heavy-atom (EHA) perturber layer in a desired manner, it provides useful means of accelerating the T1 → S1 reverse intersystem crossing (RISC) in TADF molecules without affecting the corresponding S1 → T1 process heavily. Furthermore, this strategy also promotes the utilization of host triplets through Förster mechanism during host → guest energy transfer (ET) processes, which helps to get rid of the solely dependence upon Dexter mechanism. Based on this strategy, we have successfully raised the external quantum efficiency (EQE) in 4CzPN-based devices by nearly 38% in comparison to control devices. These findings provide keen insights into the role of EHA played in TADF-based devices, offering valuable guidelines for utilizing certain TADF dyes which possess high radiative transition rate but relatively inefficient RISC.

  17. A new way towards high-efficiency thermally activated delayed fluorescence devices via external heavy-atom effect

    PubMed Central

    Zhang, Wenzhi; Jin, Jiangjiang; Huang, Zhi; Zhuang, Shaoqing; Wang, Lei

    2016-01-01

    Thermally activated delayed fluorescence (TADF) mechanism is a significant method that enables the harvesting of both triplet and singlet excitons for emission. However, up to now most efforts have been devoted to dealing with the relation between singlet-triplet splitting (ΔEST) and fluorescence efficiency, while the significance of spin-orbit coupling (SOC) is usually ignored. In this contribution, a new method is developed to realize high-efficiency TADF-based devices through simple device-structure optimizations. By inserting an ultrathin external heavy-atom (EHA) perturber layer in a desired manner, it provides useful means of accelerating the T1 → S1 reverse intersystem crossing (RISC) in TADF molecules without affecting the corresponding S1 → T1 process heavily. Furthermore, this strategy also promotes the utilization of host triplets through Förster mechanism during host → guest energy transfer (ET) processes, which helps to get rid of the solely dependence upon Dexter mechanism. Based on this strategy, we have successfully raised the external quantum efficiency (EQE) in 4CzPN-based devices by nearly 38% in comparison to control devices. These findings provide keen insights into the role of EHA played in TADF-based devices, offering valuable guidelines for utilizing certain TADF dyes which possess high radiative transition rate but relatively inefficient RISC. PMID:27439967

  18. Insights Into the Effects of Internal Variability, External Variability, and Active Sites on Heterogeneous Ice Nucleation

    NASA Astrophysics Data System (ADS)

    Beydoun, H.; Sullivan, R. C.; Polen, M.

    2015-12-01

    Heterogeneous ice nucleation (HIN) remains one of the outstanding problems in cloud physics and atmospheric science. Experimental challenges in properly simulating HIN processes with relevant atmospheric conditions have largely contributed to the absence of a consistent and comprehensive parameterization. Here we formulate a new ice active surface site-based stochastic model of HIN with the unique feature of invoking a continuum assumption on the ice nucleation activity (contact angle) of an aerosol particle's surface. The result is a particle specific property g that defines a distribution of local surface ice nucleation rates. Upon integration this yields a full freezing probability function for an ice nucleating particle. Current cold plate droplet freezing measurements provide a great resource for studying the freezing ability of many atmospheric aerosol systems. A method based on statistical significance and critical area analysis is presented that can resolve the two-dimensional nature of the ice nucleation ability of aerosol particles: variability in active sites and freezing rates along an individual particle's surface, as well as variability between two particles of the same type in an aerosol population. When applied to published experimental data, the method demonstrates its ability to comprehensively interpret droplet freezing spectra of variable particle mass and surface area concentrations. By fitting the high concentration freezing curves to a statistically significant active site density function, the lower concentration freezing curves are successfully fitted via a process of random sampling from the statistically significant distribution. Using the new scheme, comprehensive parameterizations that can track the frozen fraction of cloud droplets in larger atmospheric models are derived.

  19. Role of external oversight in quality activities: accreditation, credentialing, licensure, and deemed status.

    PubMed

    Wish, J B

    1998-12-01

    There currently exist a number of organizations which provide quality oversight to the ESRD program in the United States. The state surveyors confirm that dialysis facilities comply with Medicare's conditions of coverage, but surveyor activities have traditionally followed a quality assurance rather than a continuous quality improvement (CQI) model. State surveyors focus primarily on nursing homes, so their content knowledge of ESRD quality issues may be limited. The ESRD Networks have CQI expertise on their staffs, and their quality agenda is driven by their medical review boards, whose members bring scientific and technical expertise from the provider community. The success of the Networks in achieving quality goals has been hampered by personnel and resource limitations and by inconsistent direction by the Health Care Financing Administration (HCFA). Texas has developed a dialysis facility licensure program that partners its ESRD Network and its Medicare state surveyors in quality oversight activities. This collaboration has led to improved patient outcomes and may prove to be a model for other states. Non-Medicare payers may contract with dialysis providers based on performance specifications that exceed those of Medicare's conditions of coverage. A private credentialing mechanism for dialysis facilities that satisfies the performance specifications of all payers has been proposed but, in the absence of deemed status for Medicare survey and certification activities, is unlikely to achieve widespread acceptance. PMID:9892388

  20. Single-layer-coated surfaces with linearized reflectance versus angle of incidence: application to passive and active silicon rotation sensors

    NASA Astrophysics Data System (ADS)

    Azzam, R. M. A.; Howlader, M. M. K.; Georgiou, T. Y.

    1995-08-01

    A transparent or absorbing substrate can be coated with a transparent thin film to produce a linear reflectance-versus-angle-of-incidence response over a certain range of angles. Linearization at and near normal incidence is a special case that leads to a maximally flat response for p -polarized, s -polarized, or unpolarized light. For midrange and high-range linearization with moderate and high slopes, respectively, the best results are obtained when the incident light is s polarized. Application to a Si substrate that is coated with a SiO2 film leads to novel passive and active reflection rotation sensors. Experimental results and an error analysis of this rotation sensor are presented.

  1. Discovery and characteristics of the rapidly rotating active asteroid (62412) 2000 SY178 in the main belt

    SciTech Connect

    Sheppard, Scott S.; Trujillo, Chadwick

    2015-02-01

    We report a new active asteroid in the main belt of asteroids between Mars and Jupiter. Object (62412) 2000 SY178 exhibited a tail in images collected during our survey for objects beyond the Kuiper Belt using the Dark Energy Camera on the CTIO 4 m telescope. We obtained broadband colors of 62412 at the Magellan Telescope, which, along with 62412's low albedo, suggests it is a C-type asteroid. 62412's orbital dynamics and color strongly correlate with the Hygiea family in the outer main belt, making it the first active asteroid known in this heavily populated family. We also find 62412 to have a very short rotation period of 3.33 ± 0.01 hours from a double-peaked light curve with a maximum peak-to-peak amplitude of 0.45 ± 0.01 mag. We identify 62412 as the fastest known rotator of the Hygiea family and the nearby Themis family of similar composition, which contains several known main belt comets. The activity on 62412 was seen over one year after perihelion passage in its 5.6 year orbit. 62412 has the highest perihelion and one of the most circular orbits known for any active asteroid. The observed activity is probably linked to 62412's rapid rotation, which is near the critical period for break-up. The fast spin rate may also change the shape and shift material around 62412's surface, possibly exposing buried ice. Assuming 62412 is a strengthless rubble pile, we find the density of 62412 to be around 1500 kg m{sup −3}.

  2. Discovery and Characteristics of the Rapidly Rotating Active Asteroid (62412) 2000 SY178 in the Main Belt

    NASA Astrophysics Data System (ADS)

    Sheppard, Scott S.; Trujillo, Chadwick

    2015-02-01

    We report a new active asteroid in the main belt of asteroids between Mars and Jupiter. Object (62412) 2000 SY178 exhibited a tail in images collected during our survey for objects beyond the Kuiper Belt using the Dark Energy Camera on the CTIO 4 m telescope. We obtained broadband colors of 62412 at the Magellan Telescope, which, along with 62412's low albedo, suggests it is a C-type asteroid. 62412's orbital dynamics and color strongly correlate with the Hygiea family in the outer main belt, making it the first active asteroid known in this heavily populated family. We also find 62412 to have a very short rotation period of 3.33 ± 0.01 hours from a double-peaked light curve with a maximum peak-to-peak amplitude of 0.45 ± 0.01 mag. We identify 62412 as the fastest known rotator of the Hygiea family and the nearby Themis family of similar composition, which contains several known main belt comets. The activity on 62412 was seen over one year after perihelion passage in its 5.6 year orbit. 62412 has the highest perihelion and one of the most circular orbits known for any active asteroid. The observed activity is probably linked to 62412's rapid rotation, which is near the critical period for break-up. The fast spin rate may also change the shape and shift material around 62412's surface, possibly exposing buried ice. Assuming 62412 is a strengthless rubble pile, we find the density of 62412 to be around 1500 kg m-3.

  3. Moments applied in the rotation of massive objects in Shuttle extravehicular activity

    NASA Technical Reports Server (NTRS)

    Cousins, D.; Akin, D. L.

    1989-01-01

    Experimentally derived applied moments are presented for Space Shuttle crew EVA mission rotations of objects more massive than the human body. These levels appear to be small fractions of physiological limits; horizontal and vertical shoulder strength limits greater than 50 Nm have been established for foot-restrained, pressure-suited subjects in simulated weightlessness. The reduced level in operational EVA may be due to unfamiliarity with manual control in true weightlessness.

  4. Explosive volcanic activity on Venus: The roles of volatile contribution, degassing, and external environment

    NASA Astrophysics Data System (ADS)

    Airey, M. W.; Mather, T. A.; Pyle, D. M.; Glaze, L. S.; Ghail, R. C.; Wilson, C. F.

    2015-08-01

    We investigate the conditions that will promote explosive volcanic activity on Venus. Conduit processes were simulated using a steady-state, isothermal, homogeneous flow model in tandem with a degassing model. The response of exit pressure, exit velocity, and degree of volatile exsolution was explored over a range of volatile concentrations (H2O and CO2), magma temperatures, vent altitudes, and conduit geometries relevant to the Venusian environment. We find that the addition of CO2 to an H2O-driven eruption increases the final pressure, velocity, and volume fraction gas. Increasing vent elevation leads to a greater degree of magma fragmentation, due to the decrease in the final pressure at the vent, resulting in a greater likelihood of explosive activity. Increasing the magmatic temperature generates higher final pressures, greater velocities, and lower final volume fraction gas values with a correspondingly lower chance of explosive volcanism. Cross-sectionally smaller, and/or deeper, conduits were more conducive to explosive activity. Model runs show that for an explosive eruption to occur at Scathach Fluctus, at Venus' mean planetary radius (MPR), 4.5% H2O or 3% H2O with 3% CO2 (from a 25 m radius conduit) would be required to initiate fragmentation; at Ma'at Mons (~9 km above MPR) only ~2% H2O is required. A buoyant plume model was used to investigate plume behaviour. It was found that it was not possible to achieve a buoyant column from a 25 m radius conduit at Scathach Fluctus, but a buoyant column reaching up to ~20 km above the vent could be generated at Ma'at Mons with an H2O concentration of 4.7% (at 1300 K) or a mixed volatile concentration of 3% H2O with 3% CO2 (at 1200 K). We also estimate the flux of volcanic gases to the lower atmosphere of Venus, should explosive volcanism occur. Model results suggest explosive activity at Scathach Fluctus would result in an H2O flux of ~107 kg s-1. Were Scathach Fluctus emplaced in a single event, our model

  5. A path towards understanding the rotation-activity relation of M dwarfs with K2 mission, X-ray and UV data

    NASA Astrophysics Data System (ADS)

    Stelzer, B.; Damasso, M.; Scholz, A.; Matt, S. P.

    2016-08-01

    We study the relation between stellar rotation and magnetic activity for a sample of 134 bright, nearby M dwarfs observed in the Kepler Two-Wheel (K2) mission during campaigns C0 to C4. The K2 lightcurves yield photometrically derived rotation periods for 97 stars (79 of which without previous period measurement), as well as various measures for activity related to cool spots and flares. We find a clear difference between fast and slow rotators with a dividing line at a period of ˜10 d at which the activity level changes abruptly. All photometric diagnostics of activity (spot cycle amplitude, flare peak amplitude and residual variability after subtraction of spot and flare variations) display the same dichotomy, pointing to a quick transition between a high-activity mode for fast rotators and a low-activity mode for slow rotators. This unexplained behavior is reminiscent of a dynamo mode-change seen in numerical simulations that separates a dipolar from a multipolar regime. A substantial number of the fast rotators are visual binaries. A tentative explanation is accelerated disk evolution in binaries leading to higher initial rotation rates on the main-sequence and associated longer spin-down and activity lifetimes. We combine the K2 rotation periods with archival X-ray and UV data. X-ray, FUV and NUV detections are found for 26, 41, and 11 stars from our sample, respectively. Separating the fast from the slow rotators, we determine for the first time the X-ray saturation level separately for early- and for mid-M stars.

  6. Chromospheric activity and rotational modulation of the RS Canum Venaticorum binary V711 Tauri during 1998-2004

    NASA Astrophysics Data System (ADS)

    Cao, Dongtao; Gu, Shenghong

    2015-05-01

    We present long-term high-resolution spectroscopic observations of the very active RS Canum Venaticorum-type star V711 Tau, obtained during several observing runs from 1998 to 2004, and study its chromospheric activity. Using the spectral subtraction technique, several optical chromospheric activity indicators [including the He I D3, Na I D1, D2, Hα and Ca II infrared triplet (IRT) lines] formed at different atmospheric heights are analysed. Strong chromospheric emission supports earlier results that indicate that V711 Tau is a very active system. Two large optical flares were detected during our observations. The results suggest that the main part of chromospheric emission is attributed to the primary star of the system. The secondary also presents weak emission but is less active. The ratios of EW8542/EW8498 indicate that Ca II IRT emission arises predominantly from plage-like regions. We have found rotational modulation of chromospheric activity in the Hα and Ca II IRT lines, which suggests the presence of the chromospheric active longitudes over the surface of V711 Tau. Two active longitudes separated by about 180° were observed to dominate the activity, and the so-called flip-flop phenomenon was seen during our observations. Moreover, the chromospheric activity level shows a long-term variation that gradually increases from a deep minimum near the year 2002. A close spatial connection of photospheric spots and chromospheric active regions in both short and long timescales was found for V711 Tau.

  7. Physical activity promotion in Latin American populations: a systematic review on issues of internal and external validity

    PubMed Central

    2014-01-01

    The purpose of this review was to determine the degree to which physical activity interventions for Latin American populations reported on internal and external validity factors using the RE-AIM framework (reach & representativeness, effectiveness, adoption, implementation, maintenance). We systematically identified English (PubMed; EbscoHost) and Spanish (SCIELO; Biblioteca Virtual en Salud) language studies published between 2001 and 2012 that tested physical activity, exercise, or fitness promotion interventions in Latin American populations. Cross-sectional/descriptive studies, conducted in Brazil or Spain, published in Portuguese, not including a physical activity/fitness/exercise outcome, and with one time point assessment were excluded. We reviewed 192 abstracts and identified 46 studies that met the eligibility criteria (34 in English, 12 in Spanish). A validated 21-item RE-AIM abstraction tool was used to determine the quality of reporting across studies (0-7 = low, 8-14 = moderate, and 15-21 = high). The number of indicators reported ranged from 3–14 (mean = 8.1 ± 2.6), with the majority of studies falling in the moderate quality reporting category. English and Spanish language articles did not differ on the number of indicators reported (8.1 vs. 8.3, respectively). However, Spanish articles reported more across reach indicators (62% vs. 43% of indicators), while English articles reported more across effectiveness indicators (69% vs 62%). Across RE-AIM dimensions, indicators for reach (48%), efficacy/effectiveness (67%), and implementation (41%) were reported more often than indicators of adoption (25%) and maintenance (10%). Few studies reported on the representativeness of participants, staff that delivered interventions, or the settings where interventions were adopted. Only 13% of the studies reported on quality of life and/or potential negative outcomes, 20% reported on intervention fidelity, and 11% on cost of implementation

  8. Physical activity promotion in Latin American populations: a systematic review on issues of internal and external validity.

    PubMed

    Galaviz, Karla I; Harden, Samantha M; Smith, Erin; Blackman, Kacie Ca; Berrey, Leanna M; Mama, Scherezade K; Almeida, Fabio A; Lee, Rebecca E; Estabrooks, Paul A

    2014-06-17

    The purpose of this review was to determine the degree to which physical activity interventions for Latin American populations reported on internal and external validity factors using the RE-AIM framework (reach & representativeness, effectiveness, adoption, implementation, maintenance). We systematically identified English (PubMed; EbscoHost) and Spanish (SCIELO; Biblioteca Virtual en Salud) language studies published between 2001 and 2012 that tested physical activity, exercise, or fitness promotion interventions in Latin American populations. Cross-sectional/descriptive studies, conducted in Brazil or Spain, published in Portuguese, not including a physical activity/fitness/exercise outcome, and with one time point assessment were excluded. We reviewed 192 abstracts and identified 46 studies that met the eligibility criteria (34 in English, 12 in Spanish). A validated 21-item RE-AIM abstraction tool was used to determine the quality of reporting across studies (0-7 = low, 8-14 = moderate, and 15-21 = high). The number of indicators reported ranged from 3-14 (mean = 8.1 ± 2.6), with the majority of studies falling in the moderate quality reporting category. English and Spanish language articles did not differ on the number of indicators reported (8.1 vs. 8.3, respectively). However, Spanish articles reported more across reach indicators (62% vs. 43% of indicators), while English articles reported more across effectiveness indicators (69% vs 62%). Across RE-AIM dimensions, indicators for reach (48%), efficacy/effectiveness (67%), and implementation (41%) were reported more often than indicators of adoption (25%) and maintenance (10%). Few studies reported on the representativeness of participants, staff that delivered interventions, or the settings where interventions were adopted. Only 13% of the studies reported on quality of life and/or potential negative outcomes, 20% reported on intervention fidelity, and 11% on cost of implementation

  9. Modulation of the Relationship Between External Knee Adduction Moments and Medial Joint Contact Forces Across Subjects and Activities

    PubMed Central

    Trepczynski, Adam; Kutzner, Ines; Bergmann, Georg; Taylor, William R; Heller, Markus O

    2014-01-01

    Objective The external knee adduction moment (EAM) is often considered a surrogate measure of the distribution of loads across the tibiofemoral joint during walking. This study was undertaken to quantify the relationship between the EAM and directly measured medial tibiofemoral contact forces (Fmed) in a sample of subjects across a spectrum of activities. Methods The EAM for 9 patients who underwent total knee replacement was calculated using inverse dynamics analysis, while telemetric implants provided Fmed for multiple repetitions of 10 activities, including walking, stair negotiation, sit-to-stand activities, and squatting. The effects of the factors “subject” and “activity” on the relationships between Fmed and EAM were quantified using mixed-effects regression analyses in terms of the root mean square error (RMSE) and the slope of the regression. Results Across subjects and activities a good correlation between peak EAM and Fmed values was observed, with an overall R2 value of 0.88. However, the slope of the linear regressions varied between subjects by up to a factor of 2. At peak EAM and Fmed, the RMSE of the regression across all subjects was 35% body weight (%BW), while the maximum error was 127 %BW. Conclusion The relationship between EAM and Fmed is generally good but varies considerably across subjects and activities. These findings emphasize the limitation of relying solely on the EAM to infer medial joint loading when excessive directed cocontraction of muscles exists and call for further investigations into the soft tissue–related mechanisms that modulate the internal forces at the knee. PMID:24470261

  10. Post-Transition State Dynamics in Gas Phase Reactivity: Importance of Bifurcations and Rotational Activation.

    PubMed

    Martín-Sómer, Ana; Yáñez, Manuel; Hase, William L; Gaigeot, Marie-Pierre; Spezia, Riccardo

    2016-03-01

    Beyond the established use of thermodynamic vs kinetic control to explain chemical reaction selectivity, the concept of bifurcations on a potential energy surface (PES) is proving to be of pivotal importance with regard to selectivity. In this article, we studied by means of post-transition state (TS) direct dynamics simulations the effect that vibrational and rotational excitation at the TS may have on selectivity on a bifurcating PES. With this aim, we studied the post-TS unimolecular reactivity of the [Ca(formamide)](2+) ion, for which Coulomb explosion and neutral loss reactions compete. The PES exhibits different kinds of nonintrinsic reaction coordinate (IRC) dynamics, among them PES bifurcations, which direct the trajectories to multiple reaction paths after passing the TS. Direct dynamics simulations were used to distinguish between the bifurcation non-IRC dynamics and non-IRC dynamics arising from atomistic motions directing the trajectories away from the IRC. Overall, we corroborated the idea that kinetic selectivity often does not reduce to a simple choice between paths with different barrier heights and instead dynamical behavior after passing the TS may be crucial. Importantly, rotational excitation may play a pivotal role on the reaction selectivity favoring nonthermodynamic products.

  11. Isokinetic torque imbalances in the rotator cuff of the elite water polo player.

    PubMed

    McMaster, W C; Long, S C; Caiozzo, V J

    1991-01-01

    The specific repetitive activity of water polo, like baseball pitching, emphasizes adduction and internal rotation. This study used the Cybex II to evaluate the isokinetic strength of the rotator cuff in elite water polo players and in a group of control subjects. The water polo players were significantly stronger than the controls. Of greater importance was the confirmation of imbalances in the rotator cuff force couples of adduction/abduction and external/internal rotation. These changes are similar to those reported for pitchers. The adductors in the water polo group had gained in relative strength resulting in an increase in the adduction/abduction ratio to about 2:1. The internal rotators had gained in relative strength resulting in a decrease in the external/internal ratio to about 0.6:1. For both force couples the differences are more apparent at a slow speed. Side-to-side differences were not significant.

  12. Effect of leg rotation on hip bone mineral density measurements.

    PubMed

    Lekamwasam, Sarath; Lenora, Robolge Sumith Janaka

    2003-01-01

    Bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is widely used in the management of patients with osteoporosis. Factors, which are specific to machine or to operator, can influence the accuracy and precision of BMD estimations. We studied the effect of leg rotation by 10 degrees either internally or externally from the standard position in a group of 50 women (average age 54.9, SD = 11.1 yr) who were free of bone active diseases or medications. External rotation of leg by 10 degrees from the customary position increased the average BMD by 0.005, 0.003, and 0.036 g/cm2 in the femoral neck, trochanter, and Ward's area (p = 0.119, 0.309, and <0.001), respectively. Internal rotation of leg by 10 degrees from the customary position decreased the average BMD by 0.009, 0.005, and 0.006 g/cm2 in the femoral neck, trochanter, and Ward's area (p = <0.001, 0.008, and <0.001), respectively. The number of subjects qualified for the diagnosis of osteoporosis based on the T-scores (equal to or below -2.5) of the femoral neck and trochanter did not change significantly in three different positions (18% in the customary position and after the external rotation and 14% after the internal rotation). A significant change in the femoral neck BMD (defined as 2.77 x precision error) was seen in 12% of subjects after the internal rotation and 8% after the external rotation. Our data emphasize the need for proper positioning of the hip during DXA scanning. Malrotation of the hip can be an important confounding factor when interpreting serial BMD values.

  13. Trends in ultracool dwarf magnetism. II. The inverse correlation between X-ray activity and rotation as evidence for a bimodal dynamo

    SciTech Connect

    Cook, B. A.; Williams, P. K. G.; Berger, E.

    2014-04-10

    Observations of magnetic activity indicators in solar-type stars exhibit a relationship with rotation with an increase until a 'saturation' level and a moderate decrease in activity in the very fastest rotators ('supersaturation'). While X-ray data have suggested that this relationship is strongly violated in ultracool dwarfs (UCDs; spectral type ≳M7), the limited number of X-ray detections has prevented firm conclusions. In this paper, we analyze the X-ray activity-rotation relation in 38 UCDs. Our sample represents the largest catalog of X-ray active UCDs to date, including seven new and four previously unpublished Chandra observations presented in a companion paper. We identify a substantial number of rapidly rotating UCDs with X-ray activity extending two orders of magnitude below the expected saturation level and measure a 'supersaturation'-type anticorrelation between rotation and X-ray activity. The scatter in UCD X-ray activity at a fixed rotation is ∼3 times larger than that in earlier-type stars. We discuss several mechanisms that have been proposed to explain the data, including centrifugal stripping of the corona, and find them to be inconsistent with the observed trends. Instead, we suggest that an additional parameter correlated with both X-ray activity and rotation is responsible for the observed effects. Building on the results of Zeeman-Doppler imaging of UCD magnetic fields and our companion study of radio/X-ray flux ratios, we argue that this parameter is the magnetic field topology, and that the large scatter in UCD X-ray fluxes reflects the presence of two dynamo modes that produce distinct topologies.

  14. Trends in Ultracool Dwarf Magnetism. II. The Inverse Correlation Between X-Ray Activity and Rotation as Evidence for a Bimodal Dynamo

    NASA Astrophysics Data System (ADS)

    Cook, B. A.; Williams, P. K. G.; Berger, E.

    2014-04-01

    Observations of magnetic activity indicators in solar-type stars exhibit a relationship with rotation with an increase until a "saturation" level and a moderate decrease in activity in the very fastest rotators ("supersaturation"). While X-ray data have suggested that this relationship is strongly violated in ultracool dwarfs (UCDs; spectral type gsimM7), the limited number of X-ray detections has prevented firm conclusions. In this paper, we analyze the X-ray activity-rotation relation in 38 UCDs. Our sample represents the largest catalog of X-ray active UCDs to date, including seven new and four previously unpublished Chandra observations presented in a companion paper. We identify a substantial number of rapidly rotating UCDs with X-ray activity extending two orders of magnitude below the expected saturation level and measure a "supersaturation"-type anticorrelation between rotation and X-ray activity. The scatter in UCD X-ray activity at a fixed rotation is ~3 times larger than that in earlier-type stars. We discuss several mechanisms that have been proposed to explain the data, including centrifugal stripping of the corona, and find them to be inconsistent with the observed trends. Instead, we suggest that an additional parameter correlated with both X-ray activity and rotation is responsible for the observed effects. Building on the results of Zeeman-Doppler imaging of UCD magnetic fields and our companion study of radio/X-ray flux ratios, we argue that this parameter is the magnetic field topology, and that the large scatter in UCD X-ray fluxes reflects the presence of two dynamo modes that produce distinct topologies.

  15. Range of motion and leg rotation affect electromyography activation levels of the superficial quadriceps muscles during leg extension.

    PubMed

    Signorile, Joseph F; Lew, Karen M; Stoutenberg, Mark; Pluchino, Alessandra; Lewis, John E; Gao, Jinrun

    2014-09-01

    Leg extension (LE) is commonly used to strengthen the quadriceps muscles during training and rehabilitation. This study examined the effects of limb position (POS) and range of motion (ROM) on quadriceps electromyography (EMG) during 8 repetitions (REP) of LE. Twenty-four participants performed 8 LE REP at their 8 repetition maximum with lower limbs medially rotated (TI), laterally rotated (TO), and neutral (NEU). Each REP EMG was averaged over the first, middle, and final 0.524 rad ROM. For vastus medialis oblique (VMO), a REP × ROM interaction was detected (p < 0.02). The middle 0.524 rad produced significantly higher EMG than the initial 0.524 rad for REP 6-8 and the final 0.524 rad produced higher EMG than the initial 0.524 rad for REP 1, 2, 3, 4, 6, and 8 (p ≤ 0.05). For rectus femoris (RF), EMG activity increased across REP with TO generating the greatest activity (p < 0.001). For vastus lateralis (VL), EMG increased across REP (p < 0.001) with NEU and TO EMG increasing linearly throughout ROM and TI activity greatest during the middle 0.524 rad. We conclude that to target the VMO, the optimal ROM is the final 1.047 rad regardless of POS, while maximum EMG for the RF is generated using TO regardless of ROM. In contrast, the VL is maximally activated using TI over the first 1.047 rad ROM or in NEU over the final 0.524 rad ROM.

  16. Range of motion and leg rotation affect EMG activation levels of the superficial quadriceps muscles during leg extension.

    PubMed

    Signorile, Joseph F; Lew, Karen; Stoutenberg, Mark; Pluchino, Alessandra; Lewis, John E; Gao, Jinrun

    2014-06-30

    The leg extension (LE) is commonly used to strengthen the quadriceps muscles during training and rehabilitation. This study examined the effects of limb position (POS) and range of motion (ROM) on quadriceps electromyography (EMG) during 8 repetitions (REP) of LE. Twenty-four participants performed eight LE REP at their 8-repetition maximum with lower limbs medially rotated (TI), laterally rotated (TO), and neutral (NEU). Each REP EMG was averaged over the first, middle, and final 0.524 rad ROM. For vastus medialis oblique (VMO), a REP x ROM interaction was detected (p<0.02). The middle 0.524 rad produced significantly higher EMG than the initial 0.524 rad for REP 6-8 and the final 0.524 rad produced higher EMG than the initial 0.524 rad for REP 1, 2, 3, 4, 6, 8 (p<0.05). For rectus femoris (RF), EMG activity increased across REP with TO generating the greatest activity (p<0.001). For vastus lateralis (VL), EMG increased across REP (p<0.001) with NEU and TO EMG increasing linearly throughout ROM, and TI activity greatest during the middle 0.524 rad. We conclude that to target the VMO the optimal ROM is the final 1.047 rad regardless of POS, while maximum EMG for the RF is generated using TO regardless of ROM. In contrast, the VL is maximally activated using TI over the first 1.047 rad ROM or in NEU over the final 0.524 rad ROM.

  17. Mitigation of Alfvénic MHD Activity in the NSTX Tokamak by Externally Applied Perturbation Fields

    NASA Astrophysics Data System (ADS)

    Bortolon, Alessandro; Heidbrink, William W.; Kramer, Gerrit J.; Park, Jong-Kyu; Fredrickson, Eric D.; Lore, Jeremy D.; Podesta, Mario

    2013-10-01

    Observations from NSTX experiments demonstrate that externally applied 3D magnetic fields can be used to alter the dynamic of bursting and chirping Alfvén modes, driven by energetic beam ions. Pulses of static n = 3 fields (δB/B ~ 0.01 at the plasma edge) were applied during plasma discharges with persistent Global Alfvén Eigenmode activity (n = 7-8, 400-700 kHz). In response to the perturbations, the mode amplitude, the bursting period and the frequency sweep were reduced by a factor of 2-3. For modes of weaker bursting character, the magnetic perturbation induced a temporary transition to a saturated continuous mode. The ~5% drops of neutron emission rate during the pulses suggest perturbation of the fast ion population. Calculations of the perturbed fast-ion distribution function, made with the SPIRAL code, indicate that the 3D perturbation affects the orbits of fast ions that resonate with the bursting modes. The results represent an early demonstration of the possibility of controlling fast-ion instabilities by ``phase-space engineering'' of the fast-ion distribution function. Supported by DOE contracts No. DE-FG02-06ER54867, DE-AC02-09CH11466.

  18. Nitrogen removal from wastewater and external waste activated sludge reutilization/reduction by simultaneous sludge fermentation, denitrification and anammox (SFDA).

    PubMed

    Wang, Bo; Peng, Yongzhen; Guo, Yuanyuan; Zhao, Mengyue; Wang, Shuying

    2016-08-01

    This work demonstrates the feasibility of simultaneous nitrogen removal and external waste activated sludge (WAS) reutilization/reduction by using the synergy of sludge fermentation, denitrification and anammox processes in up-flow reactors (SFDA). Pre-treated domestic wastewater and synthetic wastewater (containing nitrite ∼20mg/L, ammonium ∼10mg/L in both) were fed to 1# and 2# SFDA, respectively. Long-term operation of 1# SFDA was investigated with achieving the peak ammonium removal rate of 0.021 and nitrite removal rate of 0.081kgN/(m(3)d) as nitrogen loading rate elevated from 0.075 to 0.106kgN/(m(3)d). Negative effect of dissolved oxygen on anammox or fermentation in the 2# SFDA was demonstrated negligible due to rapid depletion by microorganisms. Furthermore, a "net" sludge reduction of 38.8% was obtained due to sludge decay and organics consumption by denitrification. The SFDA process was expected to potentially be used for nitrogen removal and WAS reutilization/reduction in full-scale application. PMID:27140818

  19. Modeling external carbon addition in biological nutrient removal processes with an extension of the international water association activated sludge model.

    PubMed

    Swinarski, M; Makinia, J; Stensel, H D; Czerwionka, K; Drewnowski, J

    2012-08-01

    The aim of this study was to expand the International Water Association Activated Sludge Model No. 2d (ASM2d) to account for a newly defined readily biodegradable substrate that can be consumed by polyphosphate-accumulating organisms (PAOs) under anoxic and aerobic conditions, but not under anaerobic conditions. The model change was to add a new substrate component and process terms for its use by PAOs and other heterotrophic bacteria under anoxic and aerobic conditions. The Gdansk (Poland) wastewater treatment plant (WWTP), which has a modified University of Cape Town (MUCT) process for nutrient removal, provided field data and mixed liquor for batch tests for model evaluation. The original ASM2d was first calibrated under dynamic conditions with the results of batch tests with settled wastewater and mixed liquor, in which nitrate-uptake rates, phosphorus-release rates, and anoxic phosphorus uptake rates were followed. Model validation was conducted with data from a 96-hour measurement campaign in the full-scale WWTP. The results of similar batch tests with ethanol and fusel oil as the external carbon sources were used to adjust kinetic and stoichiometric coefficients in the expanded ASM2d. Both models were compared based on their predictions of the effect of adding supplemental carbon to the anoxic zone of an MUCT process. In comparison with the ASM2d, the new model better predicted the anoxic behaviors of carbonaceous oxygen demand, nitrate-nitrogen (NO3-N), and phosphorous (PO4-P) in batch experiments with ethanol and fusel oil. However, when simulating ethanol addition to the anoxic zone of a full-scale biological nutrient removal facility, both models predicted similar effluent NO3-N concentrations (6.6 to 6.9 g N/m3). For the particular application, effective enhanced biological phosphorus removal was predicted by both models with external carbon addition but, for the new model, the effluent PO4-P concentration was approximately one-half of that found from

  20. Roles of divergent and rotational winds in the kinetic energy balance during intense convective activity

    NASA Technical Reports Server (NTRS)

    Fuelberg, H. E.; Browning, P. A.

    1983-01-01

    Contributions of divergent and rotational wind components to the synoptic-scale kinetic energy balance are described using rawinsonde data at 3 and 6 h intervals from NASA's fourth Atmospheric Variability experiment. Two intense thunderstorm complexes occurred during the period. Energy budgets are described for the entire computational region and for limited volumes that enclosed storm-induced, upper level wind maxima located poleward of convection. Although small in magnitude, the divergent wind component played an important role in the cross-contour generation and horizontal flux divergence of kinetic energy. The importance of V(D) appears directly related to the presence and intensity of convection. Although K(D) usually comprised less than 10 percent of the total kinetic energy content, generation of kinetic energy by V(D) was a major factor in the creation of upper-level wind maxima to the north of the storm complexes. Omission of the divergent wind apparently would lead to serious misrepresentations of the energy balance. A random error analysis is presented to assess confidence limits in the various energy parameters.

  1. The evaluation of upper body muscle activity during the performance of external chest compressions in simulated hypogravity

    NASA Astrophysics Data System (ADS)

    Krygiel, Rebecca G.; Waye, Abigail B.; Baptista, Rafael Reimann; Heidner, Gustavo Sandri; Rehnberg, Lucas; Russomano, Thais

    2014-04-01

    BACKGROUND: This original study evaluated the electromyograph (EMG) activity of four upper body muscles: triceps brachii, erector spinae, upper rectus abdominis, and pectoralis major, while external chest compressions (ECCs) were performed in simulated Martian hypogravity using a Body Suspension Device, counterweight system, and standard full body cardiopulmonary resuscitation (CPR) mannequin. METHOD: 20 young, healthy male subjects were recruited. One hundred compressions divided into four sets, with roughly six seconds between each set to indicate 'ventilation', were performed within approximately a 1.5 minute protocol. Chest compression rate, depth and number were measured along with the subject's heart rate (HR) and rating of perceived exertion (RPE). RESULTS: All mean values were used in two-tailed t-tests using SPSS to compare +1 Gz values (control) versus simulated hypogravity values. The AHA (2005) compression standards were maintained in hypogravity. RPE and HR increased by 32% (p < 0.001) and 44% (p = 0.002), respectively, when ECCs were performed during Mars simulation, in comparison to +1 Gz. In hypogravity, the triceps brachii showed significantly less activity (p < 0.001) when compared with the other three muscles studied. The comparison of all the other muscles showed no difference at +1 Gz or in hypogravity. CONCLUSIONS: This study was among the first of its kind, however several limitations were faced which hopefully will not exist in future studies. Evaluation of a great number of muscles will allow space crews to focus on specific strengthening exercises within their current training regimes in case of a serious cardiac event in hypogravity.

  2. Rotating Vesta

    NASA Video Gallery

    Astronomers combined 146 exposures taken by NASA's Hubble SpaceTelescope to make this 73-frame movie of the asteroid Vesta's rotation.Vesta completes a rotation every 5.34 hours.› Asteroid and...

  3. Rotational moulding.

    PubMed

    Crawford, R J; Kearns, M P

    2003-10-01

    Rotational moulding promises designers attractive economics and a low-pressure process. The benefits of rotational moulding are compared here with other manufacturing methods such as injection and blow moulding. PMID:14603714

  4. Asters, Vortices, and Rotating Spirals in Active Gels of Polar Filaments

    NASA Astrophysics Data System (ADS)

    Kruse, K.; Joanny, J. F.; Jülicher, F.; Prost, J.; Sekimoto, K.

    2004-02-01

    We develop a general theory for active viscoelastic materials made of polar filaments. This theory is motivated by the dynamics of the cytoskeleton. The continuous consumption of a fuel generates a nonequilibrium state characterized by the generation of flows and stresses. Our theory applies to any polar system with internal energy consumption such as active chemical gels and cytoskeletal networks which are set in motion by active processes at work in cells.

  5. On the use of sensor fusion to reduce the impact of rotational and additive noise in human activity recognition.

    PubMed

    Banos, Oresti; Damas, Miguel; Pomares, Hector; Rojas, Ignacio

    2012-01-01

    The main objective of fusion mechanisms is to increase the individual reliability of the systems through the use of the collectivity knowledge. Moreover, fusion models are also intended to guarantee a certain level of robustness. This is particularly required for problems such as human activity recognition where runtime changes in the sensor setup seriously disturb the reliability of the initial deployed systems. For commonly used recognition systems based on inertial sensors, these changes are primarily characterized as sensor rotations, displacements or faults related to the batteries or calibration. In this work we show the robustness capabilities of a sensor-weighted fusion model when dealing with such disturbances under different circumstances. Using the proposed method, up to 60% outperformance is obtained when a minority of the sensors are artificially rotated or degraded, independent of the level of disturbance (noise) imposed. These robustness capabilities also apply for any number of sensors affected by a low to moderate noise level. The presented fusion mechanism compensates the poor performance that otherwise would be obtained when just a single sensor is considered.

  6. On the Use of Sensor Fusion to Reduce the Impact of Rotational and Additive Noise in Human Activity Recognition

    PubMed Central

    Banos, Oresti; Damas, Miguel; Pomares, Hector; Rojas, Ignacio

    2012-01-01

    The main objective of fusion mechanisms is to increase the individual reliability of the systems through the use of the collectivity knowledge. Moreover, fusion models are also intended to guarantee a certain level of robustness. This is particularly required for problems such as human activity recognition where runtime changes in the sensor setup seriously disturb the reliability of the initial deployed systems. For commonly used recognition systems based on inertial sensors, these changes are primarily characterized as sensor rotations, displacements or faults related to the batteries or calibration. In this work we show the robustness capabilities of a sensor-weighted fusion model when dealing with such disturbances under different circumstances. Using the proposed method, up to 60% outperformance is obtained when a minority of the sensors are artificially rotated or degraded, independent of the level of disturbance (noise) imposed. These robustness capabilities also apply for any number of sensors affected by a low to moderate noise level. The presented fusion mechanism compensates the poor performance that otherwise would be obtained when just a single sensor is considered. PMID:22969386

  7. Multiphosphine-Oxide Hosts for Ultralow-Voltage-Driven True-Blue Thermally Activated Delayed Fluorescence Diodes with External Quantum Efficiency beyond 20.

    PubMed

    Zhang, Jing; Ding, Dongxue; Wei, Ying; Han, Fuquan; Xu, Hui; Huang, Wei

    2016-01-20

    Highly efficient low-voltage-driven -true-blue thermally activated -delayed fluorescence diodes are realized through employing a tri-phosphine oxide host (2,2',4-tris(di(phenyl) -phosphoryl)-diphenylether (DPETPO)) with a record external quantum efficiency of 23.0% and the lowest onset voltage of 2.8 V to date.

  8. Control of Rhagoletis indifferents using Thiamethoxam and Spinosad baits under external fly pressure and its relation to rapidity of kill and residual bait activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Control of western cherry fruit fly (Rhagoletis indifferens Curran) using thiamethoxam in sucrose bait and spinosad bait in cherry orchards under external fly pressure and its relation to rapidity of kill and residual bait activity were studied in Washington and Utah in 2010 and 2011. Thiamethoxam ...

  9. Relationship between Individual External Doses, Ambient Dose Rates and Individuals' Activity-Patterns in Affected Areas in Fukushima following the Fukushima Daiichi Nuclear Power Plant Accident.

    PubMed

    Naito, Wataru; Uesaka, Motoki; Yamada, Chie; Kurosawa, Tadahiro; Yasutaka, Tetsuo; Ishii, Hideki

    2016-01-01

    The accident at Fukushima Daiichi Nuclear Power Plant on March 11, 2011, released radioactive material into the atmosphere and contaminated the land in Fukushima and several neighboring prefectures. Five years after the nuclear disaster, the radiation levels have greatly decreased due to physical decay, weathering, and decontamination operations in Fukushima. The populations of 12 communities were forced to evacuate after the accident; as of March 2016, the evacuation order has been lifted in only a limited area, and permanent habitation is still prohibited in most of the areas. In order for the government to lift the evacuation order and for individuals to return to their original residential areas, it is important to assess current and future realistic individual external doses. Here, we used personal dosimeters along with the Global Positioning System and Geographic Information System to understand realistic individual external doses and to relate individual external doses, ambient doses, and activity-patterns of individuals in the affected areas in Fukushima. The results showed that the additional individual external doses were well correlated to the additional ambient doses based on the airborne monitoring survey. The results of linear regression analysis suggested that the additional individual external doses were on average about one-fifth that of the additional ambient doses. The reduction factors, which are defined as the ratios of the additional individual external doses to the additional ambient doses, were calculated to be on average 0.14 and 0.32 for time spent at home and outdoors, respectively. Analysis of the contribution of various activity patterns to the total individual external dose demonstrated good agreement with the average fraction of time spent daily in each activity, but the contribution due to being outdoors varied widely. These results are a valuable contribution to understanding realistic individual external doses and the corresponding

  10. Relationship between Individual External Doses, Ambient Dose Rates and Individuals' Activity-Patterns in Affected Areas in Fukushima following the Fukushima Daiichi Nuclear Power Plant Accident.

    PubMed

    Naito, Wataru; Uesaka, Motoki; Yamada, Chie; Kurosawa, Tadahiro; Yasutaka, Tetsuo; Ishii, Hideki

    2016-01-01

    The accident at Fukushima Daiichi Nuclear Power Plant on March 11, 2011, released radioactive material into the atmosphere and contaminated the land in Fukushima and several neighboring prefectures. Five years after the nuclear disaster, the radiation levels have greatly decreased due to physical decay, weathering, and decontamination operations in Fukushima. The populations of 12 communities were forced to evacuate after the accident; as of March 2016, the evacuation order has been lifted in only a limited area, and permanent habitation is still prohibited in most of the areas. In order for the government to lift the evacuation order and for individuals to return to their original residential areas, it is important to assess current and future realistic individual external doses. Here, we used personal dosimeters along with the Global Positioning System and Geographic Information System to understand realistic individual external doses and to relate individual external doses, ambient doses, and activity-patterns of individuals in the affected areas in Fukushima. The results showed that the additional individual external doses were well correlated to the additional ambient doses based on the airborne monitoring survey. The results of linear regression analysis suggested that the additional individual external doses were on average about one-fifth that of the additional ambient doses. The reduction factors, which are defined as the ratios of the additional individual external doses to the additional ambient doses, were calculated to be on average 0.14 and 0.32 for time spent at home and outdoors, respectively. Analysis of the contribution of various activity patterns to the total individual external dose demonstrated good agreement with the average fraction of time spent daily in each activity, but the contribution due to being outdoors varied widely. These results are a valuable contribution to understanding realistic individual external doses and the corresponding

  11. Relationship between Individual External Doses, Ambient Dose Rates and Individuals’ Activity-Patterns in Affected Areas in Fukushima following the Fukushima Daiichi Nuclear Power Plant Accident

    PubMed Central

    Kurosawa, Tadahiro; Yasutaka, Tetsuo; Ishii, Hideki

    2016-01-01

    The accident at Fukushima Daiichi Nuclear Power Plant on March 11, 2011, released radioactive material into the atmosphere and contaminated the land in Fukushima and several neighboring prefectures. Five years after the nuclear disaster, the radiation levels have greatly decreased due to physical decay, weathering, and decontamination operations in Fukushima. The populations of 12 communities were forced to evacuate after the accident; as of March 2016, the evacuation order has been lifted in only a limited area, and permanent habitation is still prohibited in most of the areas. In order for the government to lift the evacuation order and for individuals to return to their original residential areas, it is important to assess current and future realistic individual external doses. Here, we used personal dosimeters along with the Global Positioning System and Geographic Information System to understand realistic individual external doses and to relate individual external doses, ambient doses, and activity-patterns of individuals in the affected areas in Fukushima. The results showed that the additional individual external doses were well correlated to the additional ambient doses based on the airborne monitoring survey. The results of linear regression analysis suggested that the additional individual external doses were on average about one-fifth that of the additional ambient doses. The reduction factors, which are defined as the ratios of the additional individual external doses to the additional ambient doses, were calculated to be on average 0.14 and 0.32 for time spent at home and outdoors, respectively. Analysis of the contribution of various activity patterns to the total individual external dose demonstrated good agreement with the average fraction of time spent daily in each activity, but the contribution due to being outdoors varied widely. These results are a valuable contribution to understanding realistic individual external doses and the corresponding

  12. Temporal and spatial strategies in an active place avoidance task on Carousel: a study of effects of stability of arena rotation speed in rats.

    PubMed

    Bahník, Štěpán; Stuchlík, Aleš

    2015-01-01

    The active place avoidance task is a dry-arena task used to assess spatial navigation and memory in rodents. In this task, a subject is put on a rotating circular arena and avoids an invisible sector that is stable in relation to the room. Rotation of the arena means that the subject's avoidance must be active, otherwise the subject will be moved in the to-be-avoided sector by the rotation of the arena and a slight electric shock will be administered. The present experiment explored the effect of variable arena rotation speed on the ability to avoid the to-be-avoided sector. Subjects in a group with variable arena rotation speed learned to avoid the sector with the same speed and attained the same avoidance ability as rats in a group with a stable arena rotation speed. Only a slight difference in preferred position within the room was found between the two groups. No difference was found between the two groups in the dark phase, where subjects could not use orientation cues in the room. Only one rat was able to learn the avoidance of the to-be-avoided sector in this phase. The results of the experiment suggest that idiothetic orientation and interval timing are not crucial for learning avoidance of the to-be-avoided sector. However, idiothetic orientation might be sufficient for avoiding the sector in the dark. PMID:26417540

  13. Effects of Stimulus Type and Strategy on Mental Rotation Network: An Activation Likelihood Estimation Meta-Analysis

    PubMed Central

    Tomasino, Barbara; Gremese, Michele

    2016-01-01

    We can predict how an object would look like if we were to see it from different viewpoints. The brain network governing mental rotation (MR) has been studied using a variety of stimuli and tasks instructions. By using activation likelihood estimation (ALE) meta-analysis we tested whether different MR networks can be modulated by the type of stimulus (body vs. non-body parts) or by the type of tasks instructions (motor imagery-based vs. non-motor imagery-based MR instructions). Testing for the bodily and non-bodily stimulus axis revealed a bilateral sensorimotor activation for bodily-related as compared to non-bodily-related stimuli and a posterior right lateralized activation for non-bodily-related as compared to bodily-related stimuli. A top-down modulation of the network was exerted by the MR tasks instructions with a bilateral (preferentially sensorimotor left) network for motor imagery- vs. non-motor imagery-based MR instructions and the latter activating a preferentially posterior right occipito-temporal-parietal network. The present quantitative meta-analysis summarizes and amends previous descriptions of the brain network related to MR and shows how it is modulated by top-down and bottom-up experimental factors. PMID:26779003

  14. Enhanced Oxygen Reduction Activity on Pt/C for Nafion-free, Thin, Uniform Films in Rotating Disk Electrode Studies

    SciTech Connect

    Shinozaki, Kazuma; Pivovar, Bryan S.; Kocha, Shyam S.

    2013-01-01

    Commercially available nanoparticle platinum on high surface area carbon black (Pt/HSC) electrocatalysts were characterized in rotating disk electrode (RDE) setups using varying ink formulations and film drying techniques in an attempt to obtain thin, uniform films and reproducible activity. Electrodes prepared from Nafion-free inks that were dried under an isopropyl alcohol (IPA) atmosphere produced uniform, thin films at low electrocatalyst loadings of ~4.5 mg/cm2 Pt. These Nafion-free/IPA-dried electrodes were found to exhibit oxygen reduction reaction (ORR) activities higher than conventional Nafion-based/Air-dried electrodes by a factor of ~2.8. The magnitude of mass and specific activities were determined to be im ~771 ±56 mA/mgPt and is~812 ±59 mA/cm2Pt respectively and appear to be the highest values reported for RDE measurements on Pt/HSC in 0.1M HClO4 at 20 mV/s and 25°C. Electrochemical diagnostics including ORR I-V profiles, cyclic voltammograms and electrochemical impedance spectroscopy (EIS) studies were conducted to investigate the thin film Pt/HSC electrodes and correlate results to film morphology and electrochemical activity.

  15. Diffuse neutrino intensity from the inner jets of active galactic nuclei: Impacts of external photon fields and the blazar sequence

    NASA Astrophysics Data System (ADS)

    Murase, Kohta; Inoue, Yoshiyuki; Dermer, Charles D.

    2014-07-01

    We study high-energy neutrino production in inner jets of radio-loud active galactic nuclei (AGN), taking into account effects of external photon fields and the blazar sequence. We show that the resulting diffuse neutrino intensity is dominated by quasar-hosted blazars, in particular, flat spectrum radio quasars, and that PeV-EeV neutrino production due to photohadronic interactions with broadline and dust radiation is unavoidable if the AGN inner jets are ultrahigh-energy cosmic-ray (UHECR) sources. Their neutrino spectrum has a cutoff feature around PeV energies since target photons are due to Lyα emission. Because of infrared photons provided by the dust torus, neutrino spectra above PeV energies are too hard to be consistent with the IceCube data unless the proton spectral index is steeper than 2.5, or the maximum proton energy is ≲100 PeV. Thus, the simple model has difficulty in explaining the IceCube data. For the cumulative neutrino intensity from blazars to exceed ˜10-8 GeV cm-2 s-1 sr-1, their local cosmic-ray energy generation rate would be ˜10-100 times larger than the local UHECR emissivity but is comparable to the averaged γ-ray blazar emissivity. Interestingly, future detectors such as the Askaryan Radio Array can detect ˜0.1-1 EeV neutrinos even in more conservative cases, allowing us to indirectly test the hypothesis that UHECRs are produced in the inner jets. We find that the diffuse neutrino intensity from radio-loud AGN is dominated by blazars with γ-ray luminosity of ≳1048 erg s-1, and the arrival directions of their ˜1-100 PeV neutrinos correlate with the luminous blazars detected by Fermi.

  16. Context-Dependent Neural Activation: Internally and Externally Guided Rhythmic Lower Limb Movement in Individuals With and Without Neurodegenerative Disease

    PubMed Central

    Hackney, Madeleine E.; Lee, Ho Lim; Battisto, Jessica; Crosson, Bruce; McGregor, Keith M.

    2015-01-01

    Parkinson’s disease is a neurodegenerative disorder that has received considerable attention in allopathic medicine over the past decades. However, it is clear that, to date, pharmacological and surgical interventions do not fully address symptoms of PD and patients’ quality of life. As both an alternative therapy and as an adjuvant to conventional approaches, several types of rhythmic movement (e.g., movement strategies, dance, tandem biking, and Tai Chi) have shown improvements to motor symptoms, lower limb control, and postural stability in people with PD (1–6). However, while these programs are increasing in number, still little is known about the neural mechanisms underlying motor improvements attained with such interventions. Studying limb motor control under task-specific contexts can help determine the mechanisms of rehabilitation effectiveness. Both internally guided (IG) and externally guided (EG) movement strategies have evidence to support their use in rehabilitative programs. However, there appears to be a degree of differentiation in the neural substrates involved in IG vs. EG designs. Because of the potential task-specific benefits of rhythmic training within a rehabilitative context, this report will consider the use of IG and EG movement strategies, and observations produced by functional magnetic resonance imaging and other imaging techniques. This review will present findings from lower limb imaging studies, under IG and EG conditions for populations with and without movement disorders. We will discuss how these studies might inform movement disorders rehabilitation (in the form of rhythmic, music-based movement training) and highlight research gaps. We believe better understanding of lower limb neural activity with respect to PD impairment during rhythmic IG and EG movement will facilitate the development of novel and effective therapeutic approaches to mobility limitations and postural instability. PMID:26696952

  17. Influence of crop rotation, intermediate crops, and organic fertilizers on the soil enzymatic activity and humus content in organic farming systems

    NASA Astrophysics Data System (ADS)

    Marcinkeviciene, A.; Boguzas, V.; Balnyte, S.; Pupaliene, R.; Velicka, R.

    2013-02-01

    The influence of crop rotation systems with different portions of nitrogen-fixing crops, intermediate crops, and organic fertilizers on the enzymatic activity and humus content of soils in organic farming was studied. The highest activity of the urease and invertase enzymes was determined in the soil under the crop rotation with 43% nitrogen-fixing crops and with perennial grasses applied twice per rotation. The application of manure and the growing of intermediate crops for green fertilizers did not provide any significant increase in the content of humus. The activity of urease slightly correlated with the humus content ( r = 0.30 at the significance level of 0.05 and r = 0.39 at the significance level of 0.01).

  18. Continued activity in P/2013 P5 PANSTARRS. Unexpected comet, rotational break-up, or rubbing binary asteroid?

    NASA Astrophysics Data System (ADS)

    Hainaut, O. R.; Boehnhardt, H.; Snodgrass, C.; Meech, K. J.; Deller, J.; Gillon, M.; Jehin, E.; Kuehrt, E.; Lowry, S. C.; Manfroid, J.; Micheli, M.; Mottola, S.; Opitom, C.; Vincent, J.-B.; Wainscoat, R.

    2014-03-01

    The object P/2013 P5 PANSTARRS was discovered in August 2013, displaying a cometary tail, but its orbital elements indicated that it was a typical member of the inner asteroid main belt. We monitored the object from 2013 August 30 until 2013 October 05 using the CFHT 3.6 m telescope (Mauna Kea, HI), the NTT (ESO, La Silla), the CA 1.23 m telescope (Calar Alto), the Perkins 1.8m (Lowell) and the 0.6 m TRAPPIST telescope (La Silla). We measured its nuclear radius to be r ≲ 0.25-0.29 km, and its colours g' - r' = 0.58 ± 0.05 and r' - i' = 0.23 ± 0.06, typical for an S-class asteroid, as expected for an object in the inner asteroid belt and in the vicinity of the Flora collisional family. We failed to detect any rotational light curve with an amplitude <0.05 mag and a double-peaked rotation period <20 h. The evolution of the tail during the observations was as expected from a dust tail. A detailed Finson-Probstein analysis of deep images acquired with the NTT in early September and with the CFHT in late September indicated that the object was active since at least late January 2013 until the time of the latest observations in 2013 September, with at least two peaks of activity around 2013 June 14 ± 10 d and 2013 July 22 ± 3 d. The changes of activity level and the activity peaks were extremely sharp and short, shorter than the temporal resolution of our observations (~1 d). The dust distribution was similar during these two events, with dust grains covering at least the 1-1000 μm range. The total mass ejected in grains <1 mm was estimated to be 3.0 × 106 kg and 2.6 × 107 kg around the two activity peaks. Rotational disruption cannot be ruled out as the cause of the dust ejection. We also propose that the components of a contact binary might gently rub and produce the observed emission. Volatile sublimation might also explain what appears as cometary activity over a period of 8 months. However, while main belt comets best explained by ice sublimation are found

  19. Rotational testing.

    PubMed

    Furman, J M

    2016-01-01

    The natural stimulus for the semicircular canals is rotation of the head, which also might stimulate the otolith organs. Vestibular stimulation usually induces eye movements via the vestibulo-ocular reflex (VOR). The orientation of the subject with respect to the axis of rotation and the orientation of the axis of rotation with respect to gravity together determine which labyrinthine receptors are stimulated for particular motion trajectories. Rotational testing usually includes the measurement of eye movements via a video system but might use a subject's perception of motion. The most common types of rotational testing are whole-body computer-controlled sinusoidal or trapezoidal stimuli during earth-vertical axis rotation (EVAR), which stimulates primarily the horizontal semicircular canals bilaterally. Recently, manual impulsive rotations, known as head impulse testing (HIT), have been developed to assess individual horizontal semicircular canals. Most types of rotational stimuli are not used routinely in the clinical setting but may be used in selected research environments. This chapter will discuss clinically relevant rotational stimuli and several types of rotational testing that are used primarily in research settings. PMID:27638070

  20. Management with willow short rotation coppice increase the functional gene diversity and functional activity of a heavy metal polluted soil.

    PubMed

    Xue, K; van Nostrand, J D; Vangronsveld, J; Witters, N; Janssen, J O; Kumpiene, J; Siebielec, G; Galazka, R; Giagnoni, L; Arenella, M; Zhou, J-Z; Renella, G

    2015-11-01

    We studied the microbial functional diversity, biochemical activity, heavy metals (HM) availability and soil toxicity of Cd, Pb and Zn contaminated soils, kept under grassland or short rotation coppice (SRC) to attenuate the risks associated with HM contamination and restore the soil ecological functions. Soil microbial functional diversity was analyzed by the GeoChip, a functional gene microarray containing probes for genes involved in nutrient cycling, metal resistance and stress response. Soil under SRC showed a higher abundance of microbial genes involved in C, N, P and S cycles and resistance to various HM, higher microbial biomass, respiration and enzyme activity rates, and lower HM availability than the grassland soil. The linkages between functional genes of soil microbial communities and soil chemical properties, HM availability and biochemical activity were also investigated. Soil toxicity and N, P and Pb availability were important factors in shaping the microbial functional diversity, as determined by CCA. We concluded that in HM contaminated soils the microbial functional diversity was positively influenced by SRC management through the reduction of HM availability and soil toxicity increase of nutrient cycling. The presented results can be important in predicting the long term environmental sustainability of plant-based soil remediation.

  1. Piezo activated mode tracking system for widely tunable mode-hop-free external cavity mid-IR semiconductor lasers

    NASA Technical Reports Server (NTRS)

    Wysocki, Gerard (Inventor); Tittel, Frank K. (Inventor); Curl, Robert F. (Inventor)

    2010-01-01

    A widely tunable, mode-hop-free semiconductor laser operating in the mid-IR comprises a QCL laser chip having an effective QCL cavity length, a diffraction grating defining a grating angle and an external cavity length with respect to said chip, and means for controlling the QCL cavity length, the external cavity length, and the grating angle. The laser of claim 1 wherein said chip may be tuned over a range of frequencies even in the absence of an anti-reflective coating. The diffraction grating is controllably pivotable and translatable relative to said chip and the effective QCL cavity length can be adjusted by varying the injection current to the chip. The laser can be used for high resolution spectroscopic applications and multi species trace-gas detection. Mode-hopping is avoided by controlling the effective QCL cavity length, the external cavity length, and the grating angle so as to replicate a virtual pivot point.

  2. Control of External Kink Instability

    NASA Astrophysics Data System (ADS)

    Navratil, Gerald

    2004-11-01

    A fundamental pressure and current limiting phenomenon in magnetically confined plasmas for fusion energy is the long wavelength ideal-MHD kink mode. These modes have been extensively studied in tokamak and reversed field pinch (RFP) devices. They are characterized by significant amplitude on the boundary of the confined plasma and can therefore be controlled by manipulation of the external boundary conditions. In the past ten years, the theoretically predicted stabilizing effect of a nearby conducting wall has been documented in experiments, which opens the possibility of a significant increase in maximum stable plasma pressure. While these modes are predicted to remain unstable when the stabilizing wall is resistive, their growth rates are greatly reduced from the hydrodynamic time scale to the time scale of magnetic diffusion through the resistive wall. These resistive wall slowed kink modes have been identified as limiting phenomena in tokamak (DIII-D, PBX-M, HBT-EP, JT-60U, JET, NSTX) and RFP (HBTX, Extrap, T2R) devices. The theoretical prediction of stabilization to nearly the ideal wall pressure limit by toroidal plasma rotation and/or active feedback control using coils has recently been realized experimentally. Sustained, stable operation at double the no-wall pressure limit has been achieved. Discovery of the phenomenon of resonant field amplification by marginally stable kink modes and its role in the momentum balance of rotationally stabilized plasmas has emerged as a key feature. A theoretical framework, based on an extension of the very successful treatment of the n=0 axisymmetric mode developed in the early 1990's, to understand the stabilization mechanisms and model the performance of active feedback control systems is now established. This allows design of kink control systems for burning plasma experiments like ITER.

  3. Minimal model for spontaneous cell polarization and edge activity in oscillating, rotating and migrating cells

    NASA Astrophysics Data System (ADS)

    Raynaud, Franck; Ambühl, Mark E.; Gabella, Chiara; Bornert, Alicia; Sbalzarini, Ivo F.; Meister, Jean-Jacques; Verkhovsky, Alexander B.

    2016-04-01

    How cells break symmetry and organize activity at their edges to move directionally is a fundamental question in cell biology. Physical models of cell motility commonly incorporate gradients of regulatory proteins and/or feedback from the motion itself to describe the polarization of this edge activity. These approaches, however, fail to explain cell behaviour before the onset of polarization. We use polarizing and moving fish epidermal cells as a model system to bridge the gap between cell behaviours before and after polarization. Our analysis suggests a novel and simple principle of self-organizing cell activity, in which local cell-edge dynamics depends on the distance from the cell centre, but not on the orientation with respect to the front-back axis. We validate this principle with a stochastic model that faithfully reproduces a range of cell-migration behaviours. Our findings indicate that spontaneous polarization, persistent motion and cell shape are emergent properties of the local cell-edge dynamics controlled by the distance from the cell centre.

  4. Supercritical CO2 desorption of activated carbon loaded with 2,2,3,3-tetrafluoro-1-propanol in a rotating packed bed.

    PubMed

    Tan, Chung-Sung; Lee, Pei-Lun

    2008-03-15

    Desorption of activated carbon loaded with 2,2,3,3-tetrafluoro-1-propanol (TFP) by supercritical carbon dioxide in a rotating packed bed was investigated in this study. The experimental data show that the time required to achieve complete desorption of TFP from activated carbon in a rotating packed bed was much lower than that in a static packed bed. The reduction of desorption time is attributed to the presence of centrifugal force. The supercritical CO2 desorption efficiency in a rotating packed bed was observed to increase with increasing rotation speed, pressure, and C02 flow rate. To enhance desorption efficiency, a smaller activated carbon particle size was suggested. At low operating pressures such as 8.96 and 11.72 MPa, a better desorption efficiency was found to occur at lower temperatures in a temperature range of 305-335 K. However, at high operating pressures such as 15.86 MPa, a temperature of 315 K was found to be more appropriate for desorption, as compared to other temperatures. Due to a reduction of packed bed volume and an increase in desorption efficiency, supercritical CO2 desorption in a rotating packed bed is suggested for recovering TFP from the exhaust gases. PMID:18409651

  5. Wave-Driven Rotation In Centrifugal Mirrors

    SciTech Connect

    Abraham J. Fetterman and Nathaniel J. Fisch

    2011-03-28

    Centrifugal mirrors use supersonic rotation to provide axial confinement and enhanced stability. Usually the rotation is produced using electrodes, but these electrodes have limited the rotation to the Alfven critical ionization velocity, which is too slow to be useful for fusion. Instead, the rotation could be produced using radio frequency waves. A fixed azimuthal ripple is a simple and efficient wave that could produce rotation by harnessing alpha particle energy. This is an extension of the alpha channeling effect. The alpha particle power and efficiency in a simulated devices is sufficient to produce rotation without external energy input. By eliminating the need for electrodes, this opens new opportunities for centrifugal traps.

  6. Bridging the gap between research and practice: an assessment of external validity of community-based physical activity programs in Bogotá, Colombia, and Recife, Brazil.

    PubMed

    Paez, Diana C; Reis, Rodrigo S; Parra, Diana C; Hoehner, Christine M; Sarmiento, Olga L; Barros, Mauro; Brownson, Ross C

    2015-03-01

    For more than a decade, physical activity classes have been offered in public places at no cost to the participants in some Latin American cities, however, internal and external validity evidence of these programs is limited. The goals of this study were to assess, report, and compare the external validity of the Recreovia program (RCP) in Colombia, and the Academia da Cidade program (ACP) in Brazil. Interviews to assess external validity of the RCP and ACP were conducted in 2012. The interview guide was developed based on the RE-AIM framework. Seventeen key informants were selected to participate in the study. Interviews were recorded and transcribed verbatim. Transcripts were analyzed using a constant comparative qualitative method and experts validated common themes. RCP and ACP key informants reported that both programs reach underserved population. There is no information available about effectiveness. Both programs take place in public spaces (e.g., parks and plazas), which are selected for adoption mainly based on community demand. RCP and ACP offer free physical activity classes with educational and cultural components, have a strong organizational structure for implementation, and differ on schedule and content of classes. Funding sources were reported to play an important role on long-term maintenance. Facilitators and barriers were identified. Programs are similar in the reach and adoption elements; the main differences were found on implementation and maintenance, whereas information on effectiveness was not found. Reporting external validity of these programs is useful to bridge the gap between research and practice.

  7. Revisiting a possible relationship between solar activity and Earth rotation variability

    NASA Astrophysics Data System (ADS)

    Abarca del Rio, R.; Gambis, D.

    2011-10-01

    A variety of studies have searched to establish a possible relationship between the solar activity and earth variations (Danjon, 1958-1962; Challinor, 1971; Currie, 1980, Gambis, 1990). We are revisiting previous studies (Bourget et al, 1992, Abarca del Rio et al, 2003, Marris et al, 2004) concerning the possible relationship between solar activity variability and length of day (LOD) variations at decadal time scales. Assuming that changes in AAM for the entire atmosphere are accompanied by equal, but opposite, changes in the angular momentum of the earth it is possible to infer changes in LOD from global AAM time series, through the relation : delta (LOD) (ms) = 1.68 10^29 delta(AAM) (kgm2/s) (Rosen and Salstein, 1983), where δ(LOD) is given in milliseconds. Given the close relationship at seasonal to interannual time's scales between LOD and the Atmospheric Angular Momentum (AAM) (see Abarca del Rio et al., 2003) it is possible to infer from century long atmospheric simulations what may have been the variability in the associated LOD variability throughout the last century. In the absence of a homogeneous century long LOD time series, we take advantage of the recent atmospheric reanalyzes extending since 1871 (Compo, Whitaker and Sardeshmukh, 2006). The atmospheric data (winds) of these reanalyzes allow computing AAM up to the top of the atmosphere; though here only troposphere data (up to 100 hPa) was taken into account.

  8. The effect of external magnetic fields on the catalytic activity of Pd nanoparticles in Suzuki cross-coupling reactions.

    PubMed

    Gao, Lei; Wang, Changlai; Li, Ren; Li, Ran; Chen, Qianwang

    2016-04-21

    Pd nanoparticles supported on Co3[Co(CN)6]2 nanoparticles (marked as Pd@Co3[Co(CN)6]2 nanoparticles) were prepared as catalysts for the Suzuki cross-coupling reaction under external magnetic fields (MFs). It is shown that a weak external MF can increase the rate of the Suzuki cross-coupling reaction at room temperature, and with the increase of the strength of external MFs the reaction rate also increased. At 30 °C, the yield was increased by nearly 50% under a 0.5 T external MF after 24 hours compared to that without a MF applied. Theoretical calculations revealed that the adsorption energy changed from -1.07 to -1.12 eV in the presence of MFs, which increased by 5% compared with the absence of MFs, leading to a lower total energy of the adsorption system, which is beneficial to the reaction. From the analysis of the partial density states, it could be seen that the 2p orbital of the carbon atom in bromobenzene and the 4d orbital of the Pd atom overlap more closely in the presence of MFs, which is beneficial for the electron transfer from the Pd substrate to the bromobenzene molecule. This study is helpful in understanding the interaction between MFs and catalysts and regulating the process of catalytic reactions via MFs. PMID:27043428

  9. Externalizing Problems in Fifth Grade: Relations with Productive Activity, Maternal Sensitivity, and Harsh Parenting from Infancy through Middle Childhood

    ERIC Educational Resources Information Center

    Bradley, Robert H.; Corwyn, Robert F.

    2007-01-01

    This study used data from the National Institute of Child Health and Human Development's Study of Early Child Care and Youth Development to examine relations between parenting, self-control, and externalizing behavior from infancy through 5th grade. Results indicate that self-control measured during middle childhood mediates relations between…

  10. Active retroreflector with in situ beam analysis to measure the rotational orientation in conjunction with a laser tracker

    NASA Astrophysics Data System (ADS)

    Hofherr, O.; Wachten, C.; Müller, C.; Reinecke, H.

    2013-04-01

    High precision optical non-contact position measurement is a key technology in modern engineering. Laser trackers (LT) can determine accurately x-y-z coordinates of passive retroreflectors. Next-generation systems answer the additional need to measure an object`s rotational orientation (pitch, yaw, roll). These devices are based either on photogrammetry or on enhanced retroreflectors. However, photogrammetry relies on costly camera systems and time-consuming image processing. Enhanced retroreflectors analyze the LT`s beam but are restricted in roll angle measurements. In the past we have presented a new method [1][2] to measure all six degrees of freedom in conjunction with a LT. Now we dramatically optimized the method and designed a new prototype, e.g. taking into consideration optical alignment, reduced power loss, highly optimized measuring signals and higher resolution. A method is described that allows compensating the influence of the LT's beam offset during tracking the active retroreflector. We prove the functionality of the active retroreflector with the LT and, furthermore, demonstrate the capability of the system to characterize the tracking behavior of a LT. The measurement range for the incident laser beam is +/-12° with a resolution of 0.6".

  11. Rotating Wavepackets

    ERIC Educational Resources Information Center

    Lekner, John

    2008-01-01

    Any free-particle wavepacket solution of Schrodinger's equation can be converted by differentiations to wavepackets rotating about the original direction of motion. The angular momentum component along the motion associated with this rotation is an integral multiple of [h-bar]. It is an "intrinsic" angular momentum: independent of origin and…

  12. Linear and nonlinear magneto-optical rotation on the narrow strontium intercombination line

    NASA Astrophysics Data System (ADS)

    Pandey, K.; Kwong, C. C.; Pramod, M. S.; Wilkowski, D.

    2016-05-01

    In the presence of an external static magnetic field, an atomic gas becomes optically active, showing magneto-optical rotation. In the saturated regime, the coherences among the excited substates give a nonlinear contribution to the rotation of the light polarization. In contrast with the linear magneto-optical rotation, the nonlinear counterpart is insensitive to Doppler broadening. By varying the temperature of a cold strontium gas, we observe both regimes by driving the J =0 →J =1 transition on the intercombination line. For this narrow transition, the sensitivity to the static magnetic field is typically three orders of magnitude larger than for a standard broad alkali-metal transition.

  13. Sky-Blue Organic Light Emitting Diode with 37% External Quantum Efficiency Using Thermally Activated Delayed Fluorescence from Spiroacridine-Triazine Hybrid.

    PubMed

    Lin, Ting-An; Chatterjee, Tanmay; Tsai, Wei-Lung; Lee, Wei-Kai; Wu, Meng-Jung; Jiao, Min; Pan, Kuan-Chung; Yi, Chih-Lung; Chung, Chin-Lung; Wong, Ken-Tsung; Wu, Chung-Chih

    2016-08-01

    Extremely efficient sky-blue organic electroluminescence with external quantum efficiency of ≈37% is achieved in a conventional planar device structure, using a highly efficient thermally activated delayed fluorescence emitter based on the spiroacridine-triazine hybrid and simultaneously possessing nearly unitary (100%) photoluminescence quantum yield, excellent thermal stability, and strongly horizontally oriented emitting dipoles (with a horizontal dipole ratio of 83%). PMID:27271917

  14. Changes in the biological activity of chestnut soils upon the long-term application of fertilizers in a rotation with oil-bearing crops

    NASA Astrophysics Data System (ADS)

    Eleshev, R. E.; Bakenova, Z. B.

    2012-11-01

    Experimental studies showed that irrigated chestnut soils on the piedmont of the Zailiiskiy Alatau Range are characterized by the moderate activity of the hydrolytic and redox enzymes. The use of these soils in the crop rotation system increases the hydrolytic activity of the enzymes (invertase, urease, and ATP synthase) by 30% in comparison with the monoculture; at the same time, it does not have a significant impact on the changes in the biological activity of the redox enzymes (catalase and dehydrogenase). The hydrolytic activity of the soils is activated to a greater extent in the crop rotation and in the monoculture against the background application of organic fertilizers. In this case, the recommended rates of mineral fertilizers do not inhibit the activity of the hydrolytic and redox enzymes. An increase in the hydrolytic activity of the enzymes directly affects the yield of oilseed flax. Therefore, indices of the hydrolytic activity of soils can be used as a test for the diagnostics of the efficiency of fertilizers both in crop rotation and monoculture systems.

  15. Mechanism of depolarization of rat cortical synaptosomes at submicromolar external Ca2+ activity. The use of Ca2+ buffers to control the synaptosomal membrane potential.

    PubMed Central

    Schmalzing, G

    1985-01-01

    Rat cortical synaptosomes responded to a reduction of external Ca2+ from pCa 3.5 to pCa 4.8 in the absence of MgCl2 with a slight decrease of internal K+ and an increase of Na+. The effects were prevented by tetrodotoxin or millimolar concentrations of MgCl2. Further lowering of external pCa to 7.7 with N-hydroxyethylethylenediaminetriacetate evoked a rapid fall of internal K+, which was specifically blocked by Ruthenium Red; tetrodotoxin and nifedipine were ineffective. A linear relationship was established between K+ and methyltriphenylphosphonium cation distribution ratios by varying external pCa between 4.8 and 7.7, indicating that K+ efflux resulted from a depolarization of the plasma membrane. An increase of Na+ permeability was suggested by the synaptosomes' gain of Na+ and the disappearance of the depolarization in an Na+-free sucrose medium. According to the constant field equation, the permeability ratio PNa/PK increased from 0.029 at pCa4.8 to 0.090 at pCa 7.7 with plasma membrane potentials of -74mV and -47mV, respectively. Since the plasma membrane responded to variation of external Ca2+ activities in the micromolar range with a graded and sustained depolarization, the use of Ca2+ buffers to control membrane potentials is suggested. PMID:3977854

  16. The effect of external magnetic fields on the catalytic activity of Pd nanoparticles in Suzuki cross-coupling reactions

    NASA Astrophysics Data System (ADS)

    Gao, Lei; Wang, Changlai; Li, Ren; Li, Ran; Chen, Qianwang

    2016-04-01

    Pd nanoparticles supported on Co3[Co(CN)6]2 nanoparticles (marked as Pd@Co3[Co(CN)6]2 nanoparticles) were prepared as catalysts for the Suzuki cross-coupling reaction under external magnetic fields (MFs). It is shown that a weak external MF can increase the rate of the Suzuki cross-coupling reaction at room temperature, and with the increase of the strength of external MFs the reaction rate also increased. At 30 °C, the yield was increased by nearly 50% under a 0.5 T external MF after 24 hours compared to that without a MF applied. Theoretical calculations revealed that the adsorption energy changed from -1.07 to -1.12 eV in the presence of MFs, which increased by 5% compared with the absence of MFs, leading to a lower total energy of the adsorption system, which is beneficial to the reaction. From the analysis of the partial density states, it could be seen that the 2p orbital of the carbon atom in bromobenzene and the 4d orbital of the Pd atom overlap more closely in the presence of MFs, which is beneficial for the electron transfer from the Pd substrate to the bromobenzene molecule. This study is helpful in understanding the interaction between MFs and catalysts and regulating the process of catalytic reactions via MFs.Pd nanoparticles supported on Co3[Co(CN)6]2 nanoparticles (marked as Pd@Co3[Co(CN)6]2 nanoparticles) were prepared as catalysts for the Suzuki cross-coupling reaction under external magnetic fields (MFs). It is shown that a weak external MF can increase the rate of the Suzuki cross-coupling reaction at room temperature, and with the increase of the strength of external MFs the reaction rate also increased. At 30 °C, the yield was increased by nearly 50% under a 0.5 T external MF after 24 hours compared to that without a MF applied. Theoretical calculations revealed that the adsorption energy changed from -1.07 to -1.12 eV in the presence of MFs, which increased by 5% compared with the absence of MFs, leading to a lower total energy of the

  17. Membrane-Active Sequences within gp41 Membrane Proximal External Region (MPER) Modulate MPER-Containing Peptidyl Fusion Inhibitor Activity and the Biosynthesis of HIV-1 Structural Proteins

    PubMed Central

    Zhang, Si Min; Jejcic, Alenka; Tam, James P.; Vahlne, Anders

    2015-01-01

    The membrane proximal external region (MPER) is a highly conserved membrane-active region located at the juxtamembrane positions within class I viral fusion glycoproteins and essential for membrane fusion events during viral entry. The MPER in the human immunodeficiency virus type I (HIV-1) envelope protein (Env) interacts with the lipid bilayers through a cluster of tryptophan (Trp) residues and a C-terminal cholesterol-interacting motif. The inclusion of the MPER N-terminal sequence contributes to the membrane reactivity and anti-viral efficacy of the first two anti-HIV peptidyl fusion inhibitors T20 and T1249. As a type I transmembrane protein, Env also interacts with the cellular membranes during its biosynthesis and trafficking. Here we investigated the roles of MPER membrane-active sequences during both viral entry and assembly, specifically, their roles in the design of peptidyl fusion inhibitors and the biosynthesis of viral structural proteins. We found that elimination of the membrane-active elements in MPER peptides, namely, penta Trp→alanine (Ala) substitutions and the disruption of the C-terminal cholesterol-interacting motif through deletion inhibited the anti-viral effect against the pseudotyped HIV-1. Furthermore, as compared to C-terminal dimerization, N-terminal dimerization of MPER peptides and N-terminal extension with five helix-forming residues enhanced their anti-viral efficacy substantially. The secondary structure study revealed that the penta-Trp→Ala substitutions also increased the helical content in the MPER sequence, which prompted us to study the biological relevance of such mutations in pre-fusion Env. We observed that Ala mutations of Trp664, Trp668 and Trp670 in MPER moderately lowered the intracellular and intraviral contents of Env while significantly elevating the content of another viral structural protein, p55/Gag and its derivative p24/capsid. The data suggest a role of the gp41 MPER in the membrane-reactive events during

  18. Chromospherically active stars. IX - HD 33798 = V390 Auirigae - A lithium-rich rapidly rotating single giant

    NASA Technical Reports Server (NTRS)

    Fekel, Francis C.; Marschall, Laurence A.

    1991-01-01

    Results are presented of spectroscopic observations of HD 33798 obtained to determine if this star is a short-period binary and to examine its evolutionary status. Analysis of 40 radial velocities indicates no periodic velocity variations, suggesting that the star is single, so its rapid rotation is highly unusual. This rotation is inconsistent with the rotational brake hypothesis advanced by Gray (1989). It is proposed that HD 33798 is in a post-main-sequence phase of evolution. Its space motion is similar to FK Com, suggesting that it is a coalesced binary in the process of spinning down. Scenarios are presented to explain its large lithium abundance. A version in which material is transferred from a rapidly rotating core is suggested as the most likely.

  19. Rotational Energy.

    ERIC Educational Resources Information Center

    Lockett, Keith

    1988-01-01

    Demonstrates several objects rolling down a slope to explain the energy transition among potential energy, translational kinetic energy, and rotational kinetic energy. Contains a problem from Galileo's rolling ball experiment. (YP)

  20. Solar rotation.

    NASA Astrophysics Data System (ADS)

    Dziembowski, W.

    Sunspot observations made by Johannes Hevelius in 1642 - 1644 are the first ones providing significant information about the solar differential rotation. In modern astronomy the determination of the rotation rate is done in a routine way by measuring positions of various structures on the solar surface as well as by studying the Doppler shifts of spectral lines. In recent years a progress in helioseismology enabled determination of the rotation rate in the layers inaccessible for direct observations. There are still uncertainties concerning, especially, the temporal variations of the rotation rate and its behaviour in the radiative interior. We are far from understanding the observations. Theoretical works have not yet resulted in a satisfactory model for the angular momentum transport in the convective zone.

  1. The role of rotational excitation in the activated dissociative chemisorption of vibrationally excited methane on Ni(100).

    PubMed

    Juurlink, L B; Smith, R R; Utz, A L

    2000-01-01

    We have measured the sticking probability of methane excited to v = 1 of the v3 antisymmetric C-H stretching vibration on a clean Ni(100) surface as a function of rotational state (J = 0, 1, 2 and 3) and have investigated the effect of Coriolis-mixing on reactivity. The data span a wide range of kinetic energies (9-49 kJ mol-1) and indicate that rotational excitation does not alter reactivity by more than a factor of two, even at low molecular speeds that allow for considerable rotation of the molecule during the interaction with the surface. In addition, rotation-induced Coriolis-splitting of the v3 mode into F+, F0 and F- states does not significantly affect the reactivity for J = 1 at 49 kJ mol-1 translational energy, even though the nuclear motions of these states differ. The lack of a pronounced rotational energy effect in methane dissociation on Ni(100) suggests that our previous results for (v = 1, v3, J = 2) are representative of all rovibrational sublevels of this vibrational mode. These experiments shed light on the relative importance of rotational hindering and dynamical steering mechanisms in the dissociative chemisorption on Ni(100) and guide future attempts to accurately model methane dissociation on nickel surfaces.

  2. A high-resolution spectroscopic survey of late-type stars: chromospheric activity, rotation, kinematics, and age

    NASA Astrophysics Data System (ADS)

    López-Santiago, J.; Montes, D.; Gálvez-Ortiz, M. C.; Crespo-Chacón, I.; Martínez-Arnáiz, R. M.; Fernández-Figueroa, M. J.; de Castro, E.; Cornide, M.

    2010-05-01

    Aims: We present a compilation of spectroscopic data from a survey of 144 chromospherically active young stars in the solar neighborhood, which may be used to investigate different aspects of its formation and evolution in terms of kinematics and stellar formation history. The data have already been used by us in several studies. With this paper, we make all these data accessible to the scientific community for future studies on different topics. Methods: We performed spectroscopic observations with echelle spectrographs to cover the entirety of the optical spectral range simultaneously. Standard data reduction was performed with the IRAF echelle package. We applied the spectral subtraction technique to reveal chromospheric emission in the stars of the sample. The equivalent width of chromospheric emission lines was measured in the subtracted spectra and then converted to fluxes using equivalent width-flux relationships. Radial and rotational velocities were determined by the cross-correlation technique. Kinematics, equivalent widths of the lithium line λ6707.8 Å and spectral types were also determined. Results: A catalog of spectroscopic data is compiled: radial and rotational velocities, space motion, equivalent widths of optical chromospheric activity indicators from Ca II H & K to the calcium infrared triplet and the lithium line in λ6708 Å. Fluxes in the chromospheric emission lines and R'_HK are also determined for each observation of a star in the sample. We used these data to investigate the emission levels of our stars. The study of the Hα emission line revealed two different populations of chromospheric emitters in the sample, clearly separated in the logFHα/Fbol - (V-J) diagram. The dichotomy may be associated with the age of the stars. Based on observations made with the 2.2 m telescope of the German-Spanish Astronomical Centre, Calar Alto (Almería, Spain), operated jointly by the Max-Planck-Institute for Astronomy, Heidelberg, and the Spanish

  3. Externally heated thermal battery

    NASA Astrophysics Data System (ADS)

    Pracchia, Louis; Vetter, Ronald F.; Rosenlof, Darwin

    1991-04-01

    A thermal battery activated by external heat comprising an anode (e.g., composed of a lithium-aluminum alloy), a cathode (e.g., composed of iron disulfide), and an electrolyte (e.g., a lithium chloride-potassium chloride eutectic) with the electrolyte inactive at ambient temperature but activated by melting at a predetermined temperature when exposed to external heating is presented. The battery can be used as a sensor or to ignite pyrotechnic and power electronic devices in a system for reducing the hazard of ordnance exposed to detrimental heating. A particular application is the use of the battery to activate a squib to function in conjunction with one or more other components to vent an ordnance case in order to prevent its explosion in a fire.

  4. The effects of a rotator cuff tear on activities of daily living in older adults: A kinematic analysis.

    PubMed

    Vidt, Meghan E; Santago, Anthony C; Marsh, Anthony P; Hegedus, Eric J; Tuohy, Christopher J; Poehling, Gary G; Freehill, Michael T; Miller, Michael E; Saul, Katherine R

    2016-02-29

    Rotator cuff tears (RCT) in older individuals may compound age-associated physiological changes and impact their ability to perform daily functional tasks. Our objective was to quantify thoracohumeral kinematics for functional tasks in 18 older adults (mean age=63.3±2.2), and compare findings from nine with a RCT to nine matched controls. Motion capture was used to record kinematics for 7 tasks (axilla wash, forward reach, functional pull, hair comb, perineal care, upward reach to 90°, upward reach to 105°) spanning the upper limb workspace. Maximum and minimum joint angles and motion excursion for the three thoracohumeral degrees of freedom (elevation plane, elevation, axial rotation) were identified for each task and compared between groups. The RCT group used greater minimum elevation angles for axilla wash and functional pull (p≤0.0124) and a smaller motion excursion for functional pull (p=0.0032) compared to the control group. The RCT group also used a more internally rotated maximum axial rotation angle than controls for functional reach, functional pull, hair comb, and upward reach to 105° (p≤0.0494). The most differences between groups were observed for axial rotation, with the RCT group using greater internal rotation to complete functional tasks, and significant differences between groups were identified for all three thoracohumeral degrees of freedom for functional pull. We conclude that older adults with RCT used more internal rotation to perform functional tasks than controls. The kinematic differences identified in this study may have consequences for progression of shoulder damage and further functional impairment in older adults with RCT. PMID:26879327

  5. Differential Rotation of the Active G5 V Star κ1 Ceti: Photometry from the MOST Satellite

    NASA Astrophysics Data System (ADS)

    Rucinski, Slavek M.; Walker, Gordon A. H.; Matthews, Jaymie M.; Kuschnig, Rainer; Shkolnik, Evgenya; Marchenko, Sergey; Bohlender, David A.; Guenther, D. B.; Moffat, Anthony F. J.; Sasselov, Dimitar; Weiss, Werner W.

    2004-12-01

    About 30.5 days of nearly uninterrupted broadband photometry of the solar-type star κ1 Ceti, obtained with the MOST (Microvariability and Oscillations of Stars) satellite, shows evidence for two large starspots with different rotation periods of 8.9 and ~9.3 days (ΔΩ/Ω~=4%). Ground-based measurements of Ca II H and K emission in 2002 and 2003 reveal variations in chromospheric activity with a period of about 9.3 days. The data were obtained during the MOST commissioning phase. When the data are combined with historical observations, they indicate that the 9.3 day spot has been stable in its period for over 30 yr. The photometry, with a sampling rate of approximately once per minute, was also used to search for acoustic (p-mode) oscillations in the star. We detect no clear evidence for p-modes in the κ1 Ceti photometry, with a noise level around 7-9 μmag at frequencies in the range of 0.5-4 mHz (3 σ detection limit of 21-27 μmag). There were no flares or planetary transits during 30.5 days of MOST monitoring with light amplitudes greater than 2 mmag (durations >200 minutes) and 3 mmag (2-200 minute durations). While this rules out any close-in planets with Jupiter diameters >=0.5 and orbital inclinations close to 90°, the scatter in differential radial velocities permit a close giant planet in a more highly inclined orbit. Based on data obtained with the MOST satellite, a Canadian Space Agency mission jointly operated by Dynacon, Inc., the University of Toronto Institute of Aerospace Studies, and the University of British Columbia.

  6. External Beam Therapy (EBT)

    MedlinePlus

    ... Physician Resources Professions Site Index A-Z External Beam Therapy (EBT) External beam therapy (EBT) is a ... follow-up should I expect? What is external beam therapy and how is it used? External beam ...

  7. Mitigation of Alfvén activity in a tokamak by externally applied static 3D fields.

    PubMed

    Bortolon, A; Heidbrink, W W; Kramer, G J; Park, J-K; Fredrickson, E D; Lore, J D; Podestà, M

    2013-06-28

    The application of static magnetic field perturbations to a tokamak plasma is observed to alter the dynamics of high-frequency bursting Alfvén modes that are driven unstable by energetic ions. In response to perturbations with an amplitude of δB/B∼0.01 at the plasma boundary, the mode amplitude is reduced, the bursting frequency is increased, and the frequency chirp is smaller. For modes of weaker bursting character, the magnetic perturbation induces a temporary transition to a saturated continuous mode. Calculations of the perturbed distribution function indicate that the 3D perturbation affects the orbits of fast ions that resonate with the bursting modes. The experimental evidence represents an important demonstration of the possibility of controlling fast-ion instabilities through "phase-space engineering" of the fast-ion distribution function, by means of externally applied perturbation fields.

  8. Mitigation of Alfvén Activity in a Tokamak by Externally Applied Static 3D Fields

    NASA Astrophysics Data System (ADS)

    Bortolon, A.; Heidbrink, W. W.; Kramer, G. J.; Park, J.-K.; Fredrickson, E. D.; Lore, J. D.; Podestà, M.

    2013-06-01

    The application of static magnetic field perturbations to a tokamak plasma is observed to alter the dynamics of high-frequency bursting Alfvén modes that are driven unstable by energetic ions. In response to perturbations with an amplitude of δB/B˜0.01 at the plasma boundary, the mode amplitude is reduced, the bursting frequency is increased, and the frequency chirp is smaller. For modes of weaker bursting character, the magnetic perturbation induces a temporary transition to a saturated continuous mode. Calculations of the perturbed distribution function indicate that the 3D perturbation affects the orbits of fast ions that resonate with the bursting modes. The experimental evidence represents an important demonstration of the possibility of controlling fast-ion instabilities through “phase-space engineering” of the fast-ion distribution function, by means of externally applied perturbation fields.

  9. A catalog of rotational and radial velocities for evolved stars

    NASA Astrophysics Data System (ADS)

    de Medeiros, J. R.; Mayor, M.

    1999-11-01

    Rotational and radial velocities have been measured for about 2000 evolved stars of luminosity classes IV, III, II and Ib covering the spectral region F, G and K. The survey was carried out with the CORAVEL spectrometer. The precision for the radial velocities is better than 0.30 km s-1, whereas for the rotational velocity measurements the uncertainties are typically 1.0 km s-1 for subgiants and giants and 2.0 km s-1 for class II giants and Ib supergiants. These data will add constraints to studies of the rotational behaviour of evolved stars as well as solid informations concerning the presence of external rotational brakes, tidal interactions in evolved binary systems and on the link between rotation, chemical abundance and stellar activity. In this paper we present the rotational velocity v sin i and the mean radial velocity for the stars of luminosity classes IV, III and II. Based on observations collected at the Haute--Provence Observatory, Saint--Michel, France and at the European Southern Observatory, La Silla, Chile. Table \\ref{tab5} also available in electronic form at CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

  10. Motion sickness and gastric myoelectric activity as a function of speed of rotation of a circular vection drum

    NASA Technical Reports Server (NTRS)

    Hu, Senqi; Stern, Robert M.; Vasey, Michael W.; Koch, Kenneth L.

    1989-01-01

    Motion sickness symptoms and electrogastrograms (EGGs) were obtained from 60 healthy subjects while they viewed an optokinetic drum rotated at one of four speeds: 15, 30, 60 or 90 deg/s. All subjects experienced vection, illusory self-motion. Motion sickness symptoms increased as drums speed increased up to 60 deg/s. Power, spectral intensity, of the EGG at the tachygastria frequencies (4-9 cpm) was calculated at each drum rotation speed. The correlation between the motion sickness symptoms and the power at 4-9 cpm was significant. Thus, drum rotation speed influenced the spectral power of the EGG at 4-9 cpm, tachygastria, and the intensity of motion sickness symptoms.

  11. Effect of breeding activity on the microflora of the external genitalia and in the semen of stallions, and the relationship between micro-organisms on the skin and on the external genitalia.

    PubMed

    Guimarães, T; Miranda, C; Pinto, M; Silva, E; Damásio, L; Costa, A L; Correia, M J; Duarte, J C; Cosinha, C; Lopes, G; Thompson, G; Rocha, A

    2014-12-01

    A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro-organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non-breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro-organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro-organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro-organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro-organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli.

  12. Earth Rotation

    NASA Technical Reports Server (NTRS)

    Dickey, Jean O.

    1995-01-01

    The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.

  13. Defining torpor in free-ranging bats: experimental evaluation of external temperature-sensitive radiotransmitters and the concept of active temperature.

    PubMed

    Willis, C K R; Brigham, R M

    2003-07-01

    A variety of definitions involving body temperature (Tb), metabolic rate and behavior have been used to define torpor in mammals and birds. This problem is confounded in some studies of free-ranging animals that employ only skin temperature (Tsk), a measure that approximates but may not precisely reflect Tb. We assess the accuracy of Tsk in the context of a recent definition for torpor called active temperature. We compared the active temperatures of individual big brown bats (Eptesicus fuscus), which aggregate in cavities, with solitary, foliage-roosting hoary bats (Lasiurus cinereus). In captive big brown bats, we compared Tsk and core Tb at a range of ambient temperatures for clustered and solitary roosting animals, compared Tsk and Tb during arousal from torpor, and quantified the effect of flight on warming from torpor. Hoary bats had significantly lower active temperatures than big brown bats despite having the same normothermic Tsk. Tsk was significantly lower than Tb during normothermia but often greater than Tb during torpor. Flight increased the rate of warming from torpor. This effect was more pronounced for Tsk than Tb. This suggests that bats could rely on heat generated by flight muscles to complete the final stages of arousal. Using active temperature to define torpor may underestimate torpor due to ambient cooling of external transmitters or animals leaving roosts while still torpid. Conversely, active temperature may also overestimate shallow torpor use if it is recorded during active arousal when shivering and non-shivering thermogenesis warm external transmitters. Our findings illuminate the need for laboratory studies that quantify the relationship between metabolic rate and Tsk over a range of ambient temperatures. PMID:12764630

  14. Living With A Red Dwarf: Rotation, Starspots, Activity Cycles, Coronal X-ray Activity And X-uv Irradiances Of Proxima Centauri

    NASA Astrophysics Data System (ADS)

    Jason, Merritt; Guinan, E.; Engle, S.; Pojmanski, G.

    2007-12-01

    As part of our Living with a Red Dwarf Program, we have carried out a detailed study of the radiative and plasma properties of the nearby dM5.5e star Proxima Centauri. Proxima Cen is noteworthy as the nearest star to the Sun. Because of its proximity ( 4.3 L.Y.) and membership in the α Cen system, Proxima Cen is an important star to use as a surrogate for solar-aged mid-dM stars. It is relatively bright (V = 11-mag) and has well determined observational and physical properties (MV, Teff, [Fe/H], angular diameter, mass and age). Importantly for our purposes, Proxima Cen has a reliable age of 5.5-6.0 Gyr from its association with the α Cen system in which α Cen A (G2 V) has a reliable isochronal age determination. We have analyzed 5 years of ASAS-3, V-band photometry to search for evidence of short- and long-term variations in brightness that could arise from magnetically related phenomenon (star spots, faculae, and possible UV flares). We also examine its coronal X-ray emission and variations as well as the stars chromospheric and transition regions in the UV from IUE and FUSE observations. The X-UV/optical data are combined and irradiances are calculated for use in extrasolar planet studies. From the photometry we find a rotational modulation of Prot = 83.5 days, in excellent agreement with the earlier HST/FGS study of Benedict et al. (1998). The character of its light variations indicates possible differential rotation as well as a probable long-term activity cycle of 6.9 +/- 0.5 yrs. Although Proxima Cen should be a fully convective star with a different magnetic dynamo (α2) than our Sun (αΩ), its overall magnetic behavior appears to be solar-like. This research is supported by grants from NSF/RUI AST-507536 and NASA Grants NNX06AD386 and NNG04G038G. We are grateful for this support.

  15. A 12-week rehabilitation program improves body composition, pain sensation, and internal/external torques of baseball pitchers with shoulder impingement symptom.

    PubMed

    Cha, Jun-Youl; Kim, Jae-Hak; Hong, Ju; Choi, Young-Tae; Kim, Min-Ho; Cho, Ji-Hyun; Ko, Il-Gyu; Jee, Yong-Seok

    2014-02-01

    The aim of this study was to investigate the effects of a 12-week rehabilitation program on body composition, shoulder pain, and isokinetic internal/external torques of pitchers with impingement syndrome. A total of 30 pitchers were divided into 2 groups: experimental group (EG, n = 16) and control group (CG, n= 14). The rehabilitation program consisted of physical therapy, warm-up, work-out, and cool-down. As results, body weight and fat mass of EG were decreased whereas muscle mass of EG was significantly increased after the experiment. The pain degrees in resting, normal daily activity, and strenuous activity on the numeric pain rating scale were significantly decreased in the EG. The internal and external peak torques (PTs) of uninvolved and involved sides of EG were increased in EG after 12 weeks. Such results provide a deficit ratio of both sides in EG close to normal values. The ratios of internal/external PTs in EG were also close to the reference values. The internal and external total works of both sides in EG were similar to the values of PT. The fatigue indices of internal and external rotators of both sides in EG were decreased. As a conclusion, a 12-week rehabilitation program reduced the shoulder pain, improved the body composition and enhanced the isokinetic shoulder internal/external rotators in EG with impingement symptoms. Also the study suggested that the rehabilitation program evened out the ratio between internal and external rotators and lowered the fatigue level after the experiment.

  16. Measurements and evaluation of the risks due to external radiation exposures and to intake of activated elements for operational staff engaged in the maintenance of medical cyclotrons.

    PubMed

    Calandrino, R; del Vecchio, A; Parisi, R; Todde, S; De Felice, P; Savi, A; Pepe, A; Mrskova, A

    2010-06-01

    The aim of this paper is to assess the activation phenomena and to evaluate the risk of external exposure and intake doses for the maintenance staff of two medical cyclotrons. Two self-shielded cyclotrons are currently operating in the facility for the routine production of (11)C and (18)F. Four radiochemistry laboratories are linked to the cyclotrons by means of shielded radioisotope delivery lines. Radiopharmaceuticals are prepared both for the PET Diagnostic Department, where four CT-PET scanners are operating with a mean patient workload of 40 d(-1) and for [(18)F]FDG external distribution, to provide radiopharmaceuticals for other institutions. In spite of the fact that air contamination inside the radiochemistry laboratories during the synthesis represents the largest 'slice of the pie' in the evaluation of annual intake dose, potential contamination due to the activated particulate, generated during cyclotron irradiation by micro-corrosion of targets and other components potentially struck by the proton beam and generated neutrons, should be considered. In this regard, the most plausible long-lived (T(1/2) > 30 d) radioisotopes formed are: (97)Tc, (56)Co, (57)Co, (58)Co, (60)Co, (49)V, (55)Fe, (109)Cd, (65)Zn and (22)Na. The results for the operating personnel survey has revealed only low-level contamination for (65)Zn in one test, together with minor (18)F intake, probably due to the environmental dispersion of the radioisotope during the [(18)F]FDG synthesis.

  17. Effect of short term external perturbations on bacterial ecology and activities in a partial nitritation and anammox reactor.

    PubMed

    Wu, Sha; Bhattacharjee, Ananda S; Weissbrodt, David G; Morgenroth, Eberhard; Goel, Ramesh

    2016-11-01

    This research investigated the short term effects of temperature changes (lasting 2-4weeks each) from 35±2°C to 21±2°C and 13±2°C and sulfide toxicity on partial nitrification-anammox (PN/A) system. Temperatures below 20°C and sulfide content as low as 5mgSL(-1) affected both aerobic and anaerobic catabolic activities of ammonia oxidation and the expression of related functional gene markers. The activity of AOB was inversely correlated with ammonium monooxygenase (amoA) gene expression. In contrast, the activity of AMX bacteria was positively correlated with the expression of their hydrazine synthase (hzsA) gene. Although the overall activities of AMX bacteria decreased at lower temperatures, the AMX bacteria were still active at the low temperatures. The inverse correlation between amoA gene expressions and the corresponding AOB activities was surprising. 16S rDNA based high throughput amplicon sequencing revealed the dominance of Chloroflexi, Planctomycetes and Proteobacteria phyla the distribution of which changed with temperature changes. PMID:27522119

  18. Integration of crop rotation and arbuscular mycorrhiza (AM) inoculum application for enhancing AM activity to improve phosphorus nutrition and yield of upland rice (Oryza sativa L.).

    PubMed

    Maiti, Dipankar; Toppo, Neha Nancy; Variar, Mukund

    2011-11-01

    Upland rice (Oryza sativa L.) is a major crop of Eastern India grown during the wet season (June/July to September/October). Aerobic soils of the upland rice system, which are acidic and inherently phosphorus (P) limiting, support native arbuscular mycorrhizal (AM) activity. Attempts were made to improve P nutrition of upland rice by exploiting this natural situation through different crop rotations and application of AM fungal (AMF) inoculum. The effect of a 2-year crop rotation of maize (Zea mays L.) followed by horse gram (Dolichos biflorus L.) in the first year and upland rice in the second year on native AM activity was compared to three existing systems, with and without application of a soil-root-based inoculum. Integration of AM fungal inoculation with the maize-horse gram rotation had synergistic/additive effects in terms of AMF colonization (+22.7 to +42.7%), plant P acquisition (+11.2 to +23.7%), and grain yield of rice variety Vandana (+25.7 to +34.3%).

  19. Integration of crop rotation and arbuscular mycorrhiza (AM) inoculum application for enhancing AM activity to improve phosphorus nutrition and yield of upland rice (Oryza sativa L.).

    PubMed

    Maiti, Dipankar; Toppo, Neha Nancy; Variar, Mukund

    2011-11-01

    Upland rice (Oryza sativa L.) is a major crop of Eastern India grown during the wet season (June/July to September/October). Aerobic soils of the upland rice system, which are acidic and inherently phosphorus (P) limiting, support native arbuscular mycorrhizal (AM) activity. Attempts were made to improve P nutrition of upland rice by exploiting this natural situation through different crop rotations and application of AM fungal (AMF) inoculum. The effect of a 2-year crop rotation of maize (Zea mays L.) followed by horse gram (Dolichos biflorus L.) in the first year and upland rice in the second year on native AM activity was compared to three existing systems, with and without application of a soil-root-based inoculum. Integration of AM fungal inoculation with the maize-horse gram rotation had synergistic/additive effects in terms of AMF colonization (+22.7 to +42.7%), plant P acquisition (+11.2 to +23.7%), and grain yield of rice variety Vandana (+25.7 to +34.3%). PMID:21448812

  20. Comparative Rotational Dynamics of the Moon, Mercury and Titan

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.; Ferrandiz, J. M.

    2006-08-01

    Constant and periodic tidal variations in the gravitational coefficients of second harmonics of gravitational potential of the Moon, Mercury and Titan caused by the attraction of their external bodies are described analytically. On the base of a plane model of translatory-rotary motion of the above-mentioned elastic bodies on elliptical orbits the main variations in the coefficients C[20], C[22], S[22] with periods multiple to the orbit period have been obtained and evaluated. Dynamical effects in resonant rotation of the Moon, Mercury and Titan considered as an unchangeable non-spherical bodies are studied on the basis of two models: firstly, the plane motion on the unperturbed elliptic orbit; secondly, the rotation on the precessing circular orbit. Peale's hydrostatic values of Titan gravitational field parameters C [20], C[22] (Peale, 1973) and two sets of their model values are used in paper to evaluate the unperturbed, forced and resonant effects in the rotation of Titan. For Mercury we use some average equilibrium model of elastic body rotating in resonance 3:2 with orbital motion. Another model of Mercury bases on the modern radio-location data obtained by Peale grope (2004). For the Moon well known dynamical characteristics are used. Obtained Cassini's positional parameters, amplitudes of periodic librations in longitude, periods of resonant librations and others characteristics of studied celestial bodies are given in mutual comparison. On the base of the mechanism of forced relative dynamics of the shells of celestial bodies (Barkin, 2002) due to gravitational attraction of external celestial bodies and evaluated oblateness the high endogenous activity of Titan has been predicted. This fact has obtained the confirmation in data of Cassini-Huygens mission. Especially we study resonant rotation of considered celestial bodies on the base of their models with the liquid core. The fundamental regularities (generalized Cassini's laws) and new effects in their

  1. Slowly rotating thin shell gravastars

    NASA Astrophysics Data System (ADS)

    Uchikata, Nami; Yoshida, Shijun

    2016-01-01

    We construct the solutions of slowly rotating gravastars with a thin shell. In the zero-rotation limit, we consider the gravastar composed of a de Sitter core, a thin shell, and Schwarzschild exterior spacetime. The rotational effects are treated as small axisymmetric and stationary perturbations. The perturbed internal and external spacetimes are matched with a uniformly rotating thin shell. We assume that the angular velocity of the thin shell, Ω, is much smaller than the Keplerian frequency of the nonrotating gravastar, {{{Ω }}}{{k}}. The solutions within an accuracy up to the second order of {{Ω }}/{{{Ω }}}{{k}} are obtained. The thin shell matter is assumed to be described by a perfect fluid and to satisfy the dominant energy condition in the zero-rotation limit. In this study, we assume that the equation of state for perturbations is the same as that of the unperturbed solution. The spherically symmetric component of the energy density perturbations, δ {σ }0, is assumed to vanish independently of the rotation rate. Based on these assumptions, we obtain many numerical solutions and investigate properties of the rotational corrections to the structure of the thin shell gravastar.

  2. CHROMOSPHERIC MASS MOTIONS AND INTRINSIC SUNSPOT ROTATIONS FOR NOAA ACTIVE REGIONS 10484, 10486, AND 10488 USING ISOON DATA

    SciTech Connect

    Hardersen, Paul S.; Balasubramaniam, K. S.; Shkolyar, Svetlana

    2013-08-10

    This work utilizes Improved Solar Observing Optical Network continuum (630.2 nm) and H{alpha} (656.2 nm) data to: (1) detect and measure intrinsic sunspot rotations occurring in the photosphere and chromosphere, (2) identify and measure chromospheric filament mass motions, and (3) assess any large-scale photospheric and chromospheric mass couplings. Significant results from 2003 October 27-29, using the techniques of Brown et al., indicate significant counter-rotation between the two large sunspots in NOAA AR 10486 on October 29, as well as discrete filament mass motions in NOAA AR 10484 on October 27 that appear to be associated with at least one C-class solar flare.

  3. Rotational Periods and Starspot Activity of Young Solar-Type Dwarfs in the Open Cluster IC 4665

    NASA Technical Reports Server (NTRS)

    Allain, S.; Bouvier, J.; Prosser, C.; Marschall, L. A.; Laaksonen, B. D.

    1995-01-01

    We present the results of a V-band photometric monitoring survey of 15 late-type dwarfs in the young open cluster IC 4665. Low-amplitude periodic light variations are found for 8 stars and ascribed to the modulation by starspots that cover typically a few percent of the stellar disk. Periods range from 0.6 to 3.7 d, translating to equatorial velocities between 13 and 93 km/s. That no period longer than 4 d was detected suggests a relative paucity of extremely slow rotators (V(sub eq) much less than 10 km/s) among late-type dwarfs in IC 4665. The fractional number of slow rotators in IC 4665 is similar to that of Alpha Per cluster, suggesting that IC 4665 is close in age to Alpha Per (approx. 50 Myr).

  4. Shoulder rotational properties of throwing athletes.

    PubMed

    Zheng, N; Eaton, K

    2012-06-01

    Throwing arm injuries are common and often related to the shoulder external and internal rotation. Quantitative assessment may provide new insights to physical assessment and options for treatment. After having signed IRB approved consents and filled out injury questionnaires, 96 baseball pitchers were examined on both shoulders using a custom-made wireless device. The resistance onset angle (ROA), end-point angle (EPA), shoulder rotational flexibility (SRF) in both external and internal rotation, and rotational ranges of motion (ROM) of both shoulders were determined. About 34% of subjects had surgeries on their throwing arm. Another 15% of subjects had throwing arm injuries that did not require surgical treatments. The throwing arm had significantly lower internal ROA, EPA and SRF, but significantly higher external ROA, EPA and SRF than the non-throwing arm. There were significant differences in shoulder rotational properties among groups with different surgery locations. Subjects with shoulder surgeries had greater internal rotation flexibility of their throwing arm than those with surgeries on the elbow. Throwers with injury and surgery history had significantly different shoulder rotational properties. Abnormal shoulder rotational properties may be related to throwing arm injuries. A better understanding of their relationship may lead us to effective preventive measures of throwing arm injuries.

  5. Shoulder rotational properties of throwing athletes.

    PubMed

    Zheng, N; Eaton, K

    2012-06-01

    Throwing arm injuries are common and often related to the shoulder external and internal rotation. Quantitative assessment may provide new insights to physical assessment and options for treatment. After having signed IRB approved consents and filled out injury questionnaires, 96 baseball pitchers were examined on both shoulders using a custom-made wireless device. The resistance onset angle (ROA), end-point angle (EPA), shoulder rotational flexibility (SRF) in both external and internal rotation, and rotational ranges of motion (ROM) of both shoulders were determined. About 34% of subjects had surgeries on their throwing arm. Another 15% of subjects had throwing arm injuries that did not require surgical treatments. The throwing arm had significantly lower internal ROA, EPA and SRF, but significantly higher external ROA, EPA and SRF than the non-throwing arm. There were significant differences in shoulder rotational properties among groups with different surgery locations. Subjects with shoulder surgeries had greater internal rotation flexibility of their throwing arm than those with surgeries on the elbow. Throwers with injury and surgery history had significantly different shoulder rotational properties. Abnormal shoulder rotational properties may be related to throwing arm injuries. A better understanding of their relationship may lead us to effective preventive measures of throwing arm injuries. PMID:22422310

  6. Trunk rotation and hip joint range of rotation in adolescent girls with idiopathic scoliosis: does the "dinner plate" turn asymmetrically ?

    PubMed Central

    Kotwicki, Tomasz; Walczak, Agata; Szulc, Andrzej

    2008-01-01

    Background In patients with structural idiopathic scoliosis the body asymmetries involve the pelvis and the lower limbs; they are included in many theories debating the pathogenesis of idiopathic scoliosis. Methods Hip joint range of motion was studied in 158 adolescent girls, aged 10–18 years (mean 14.2 ± 2.0) with structural idiopathic scoliosis of 20–83° of Cobb angle (mean 43.0° ± 14.5°) and compared to 57 controls, sex and age matched. Hip range of rotation was examined in prone position, the pelvis level controlled with an inclinometer; hip adduction was tested in five different positions. Results In girls with structural scoliosis the symmetry of hip rotation was less frequent (p = 0.0047), the difference between left and right hip range of internal rotation was significantly higher (p = 0.0013), and the static rotational offset of the pelvis, calculated from the mid-points of rotation, revealed significantly greater (p = 0.0092) than in healthy controls. The detected asymmetries comprised no limitation of hip range of motion, but a transposition of the sector of motion, mainly towards internal rotation in one hip and external rotation in the opposite hip. The data failed to demonstrate the curve type, the Cobb angle, the angle of trunk rotation or the curve progression factor to be related to the hip joint asymmetrical range of motion. Conclusion Numerous asymmetries around the hip were detected, most of them were expressed equally in scoliotics and in controls. Pathogenic implications concern producing a "torsional offset" of muscles patterns of activation around the spine in adolescent girls with structural idiopathic scoliosis during gait. PMID:18205943

  7. The Impact of External Employment on 12th Grade Student Participation in Extracurricular Activities as a Function of School Size

    ERIC Educational Resources Information Center

    Garcia, Miguel A.

    2012-01-01

    Data from the Educational Longitudinal Study of 2002 were used to compare 11,000 high school students on school size, time spent participating in extracurricular activities (ECA), and hours spent in employment. Findings indicated that students from small schools spent more time participating in ECA than students from larger schools for equivalent…

  8. Effect of GO-Fe3O4 and rotating magnetic field on cellular metabolic activity of mammalian cells.

    PubMed

    Urbas, Karolina; Jedrzejczak-Silicka, Magdalena; Rakoczy, Rafal; Zaborski, Daniel; Mijowska, Ewa

    2016-04-01

    The effect of hybrid material-graphene flakes with Fe3O4 nanospheres (GO-Fe3O4), graphene oxide (GO) and magnetite nanospheres (Fe3O4) in rotating magnetic field on mammalian cells metabolism has been studied. Several reports shown that exposure to magnetic field may have influence on cellular membrane permeability. Thus, the aim of presented study was to determine the cellular response of L929 fibroblast cells to nanomaterials and rotating magnetic field for 8-h exposure experiment. The GO had tendency to adsorb proteins, thus cell metabolism was decreased and the effect of that mechanism was enhanced by impact of nanospheres and rotating magnetic field. The highest reduction of cellular metabolism was recorded for WST-1 and NR assays at concentration 100 µg/mL of all tested nanomaterials and magnetic induction value 10.06 mT. The lactate dehydrogenase leakage assay has shown significant changes in membrane permeability. Further studies need to be carried out to precisely determine the mechanism of that process. PMID:26809700

  9. Libration in the earth's rotation

    NASA Technical Reports Server (NTRS)

    Chao, B. F.; Liu, H. S.; Dong, D. N.; Herring, T. A.

    1991-01-01

    External luni-solar torque exerted on the difference (B-A) of the earth's two equatorial principal moments of inertia gives rise to two types of librational motions in the earth's rotation: the semidiurnal libration in spin and the prograde diurnal libration in polar motion. Formulas for the librations considering a realistic earth model and their tidal decompositions are derived and evaluated. The spin libration has a maximum peal-to-peak amplitude of 0.90 milliarcseconds, that of the polar libration is 0.06 milliarcseconds. Implications concerning their detectability and role in the tidal variation of earth rotation are discussed.

  10. The gait pattern is not impaired in subjects with external snapping hip: a comparative cross-sectional study

    PubMed Central

    2013-01-01

    Background Symptomatic external snapping hip is a painful condition, where pain in the trochantor region and limitations of daily activity dominate clinical findings. The aetiology of symptomatic external snapping hip is elusive, but previous studies have suggested that weakness of the hip abductors and an altered walking pattern may play a role in the development of symptomatic external snapping hip. The aim of this study was to compare the walking pattern and muscular activity of the hip muscles between subjects with symptomatic external snapping hip and healthy subjects. Methods Thirteen subjects with diagnosed symptomatic external snapping hip (age: 25.5 years) were matched with 13 healthy subjects (age: 25.6 years). Joint kinematics and kinetics of the lower extremity were quantified by the peak hip adduction angle; the average knee rotation range of motion (ROM) and the peak valgus knee angle after data recording using a Vicon 612 motion capture system. Muscle activity was recorded bilaterally using surface electromyography (sEMG) on five muscles: gluteus maximus, gluteus medius, tensor fascia latae, rectus femoris and biceps femoris. A paired t-test was used to evaluate differences between the two groups. Results No significant differences were found between the groups concerning the peak hip adduction angle, the average knee rotation ROM, and the static valgus knee angle. No significant between-group differences were found concerning all other kinematics, kinetics or muscle activity. In subjects with symptomatic external snapping hip activity of the gluteus medius muscle during the acceptance phase of walking was 0.58 ± 0.19 whereas the activity was 0.68±0.07 in the asymptomatic group (p=0.115). Conclusions No significant differences in the walking pattern were found between subjects with symptomatic external snapping hip and healthy subjects. This suggest that subjects with symptomatic external snapping hip does not have an impaired gait pattern. PMID

  11. Estimating Location without External Cues

    PubMed Central

    Cheung, Allen

    2014-01-01

    The ability to determine one's location is fundamental to spatial navigation. Here, it is shown that localization is theoretically possible without the use of external cues, and without knowledge of initial position or orientation. With only error-prone self-motion estimates as input, a fully disoriented agent can, in principle, determine its location in familiar spaces with 1-fold rotational symmetry. Surprisingly, localization does not require the sensing of any external cue, including the boundary. The combination of self-motion estimates and an internal map of the arena provide enough information for localization. This stands in conflict with the supposition that 2D arenas are analogous to open fields. Using a rodent error model, it is shown that the localization performance which can be achieved is enough to initiate and maintain stable firing patterns like those of grid cells, starting from full disorientation. Successful localization was achieved when the rotational asymmetry was due to the external boundary, an interior barrier or a void space within an arena. Optimal localization performance was found to depend on arena shape, arena size, local and global rotational asymmetry, and the structure of the path taken during localization. Since allothetic cues including visual and boundary contact cues were not present, localization necessarily relied on the fusion of idiothetic self-motion cues and memory of the boundary. Implications for spatial navigation mechanisms are discussed, including possible relationships with place field overdispersion and hippocampal reverse replay. Based on these results, experiments are suggested to identify if and where information fusion occurs in the mammalian spatial memory system. PMID:25356642

  12. Do changes in hand grip strength correlate with shoulder rotator cuff function?

    PubMed Central

    Herrington, Lee; Hoyle, Rebecca; Prescott, Evie; Bellamy, Nathan

    2016-01-01

    Background Shoulder pain as a result of rotator cuff pathology is one of the most common musculoskeletal complaints presenting within primary care. Assessment of hand grip strength has been proposed as an indicator of rotator cuff function. This experimental study assessed the relationship between grip strength and shoulder lateral rotator muscle strength in a number of different shoulder positions, aiming to investigate whether such a relationship existed and whether grip strength could be used as a functional assessment tool for the posterior cuff. Methods Twenty-seven healthy, physically active, volunteers (19 males, eight females) with no history of shoulder, upper limb or neck injury comprised the study group. The mean (SD) age was 19.8 (5.7) years (range 18 years to 23 years). Grip strength (measured with hand grip dynamometer) and lateral rotator strength (measured with a hand held dynamometer) was measured at neutral, 90° abduction, and 90° abduction with 90° external rotation. Results The correlation between grip strength and shoulder lateral rotation strength ranged between r = 0.91 (r2 = 0.84) and r = 0.72 (r2 = 0.52) across all positions. Conclusions A strong correlation between grip strength and lateral rotator strength was shown at all positions for both left and right hands, suggesting that assessment of grip strength could be used as a rotator cuff monitor of recruitment function. PMID:27583010

  13. Computationally efficient simulation of electrical activity at cell membranes interacting with self-generated and externally imposed electric fields

    NASA Astrophysics Data System (ADS)

    Agudelo-Toro, Andres; Neef, Andreas

    2013-04-01

    Objective. We present a computational method that implements a reduced set of Maxwell's equations to allow simulation of cells under realistic conditions: sub-micron cell morphology, a conductive non-homogeneous space and various ion channel properties and distributions. Approach. While a reduced set of Maxwell's equations can be used to couple membrane currents to extra- and intracellular potentials, this approach is rarely taken, most likely because adequate computational tools are missing. By using these equations, and introducing an implicit solver, numerical stability is attained even with large time steps. The time steps are limited only by the time development of the membrane potentials. Main results. This method allows simulation times of tens of minutes instead of weeks, even for complex problems. The extracellular fields are accurately represented, including secondary fields, which originate at inhomogeneities of the extracellular space and can reach several millivolts. We present a set of instructive examples that show how this method can be used to obtain reference solutions for problems, which might not be accurately captured by the traditional approaches. This includes the simulation of realistic magnitudes of extracellular action potential signals in restricted extracellular space. Significance. The electric activity of neurons creates extracellular potentials. Recent findings show that these endogenous fields act back onto the neurons, contributing to the synchronization of population activity. The influence of endogenous fields is also relevant for understanding therapeutic approaches such as transcranial direct current, transcranial magnetic and deep brain stimulation. The mutual interaction between fields and membrane currents is not captured by today's concepts of cellular electrophysiology, including the commonly used activation function, as those concepts are based on isolated membranes in an infinite, isopotential extracellular space. The

  14. Vertical-axis rotations and deformation along the active strike-slip El Tigre Fault (Precordillera of San Juan, Argentina) assessed through palaeomagnetism and anisotropy of magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Fazzito, Sabrina Y.; Rapalini, Augusto E.; Cortés, José M.; Terrizzano, Carla M.

    2016-05-01

    Palaeomagnetic data from poorly consolidated to non-consolidated late Cenozoic sediments along the central segment of the active El Tigre Fault (Central-Western Precordillera of the San Juan Province, Argentina) demonstrate broad cumulative deformation up to ~450 m from the fault trace and reveal clockwise and anticlockwise vertical-axis rotations of variable magnitude. This deformation has affected in different amounts Miocene to late Pleistocene samples and indicates a complex kinematic pattern. Several inherited linear structures in the shear zone that are oblique to the El Tigre Fault may have acted as block boundary faults. Displacement along these faults may have resulted in a complex pattern of rotations. The maximum magnitude of rotation is a function of the age of the sediments sampled, with largest values corresponding to middle Miocene-lower Pliocene deposits and minimum values obtained from late Pleistocene deposits. The kinematic study is complemented by low-field anisotropy of magnetic susceptibility data to show that the local strain regime suggests a N-S stretching direction, subparallel to the strike of the main fault.

  15. International Space Station External Contamination Status

    NASA Technical Reports Server (NTRS)

    Mikatarian, Ron; Soares, Carlos

    2000-01-01

    PResentation slides examine external contamination requirements; International Space Station (ISS) external contamination sources; ISS external contamination sensitive surfaces; external contamination control; external contamination control for pre-launch verification; flight experiments and observations; the Space Shuttle Orbiter waste water dump, materials outgassing, active vacuum vents; example of molecular column density profile, modeling and analysis tools; sources of outgassing induced contamination analyzed to date, quiescent sources, observations on optical degradation due to induced external contamination in LEO; examples of typical contaminant and depth profiles; and status of the ISS system, material outgassing, thruster plumes, and optical degradation.

  16. Membranebioreactor with external membranes.

    PubMed

    Jonkers, C; Carrette, R; De Lathouwer, J; Thoeye, C

    2001-01-01

    The recent development of less expensive and more performant ultrafiltration membranes has generated a new concept in biological treatment known as membrane bioreactors (MBR). In the field of wastewater treatment, the MBR process is used as a modification of the conventional activated sludge (CAS) process, where the clarifier is replaced by a membrane module for the separation of the solid and the liquid phase. Membrane technology can, amongst others, be applied for the fast retrofit of relatively high loaded activated sludge systems to nutrient removal. In the last year Aquafin has built up extensive experience with submerged membrane systems. The research presented here was aimed at evaluating a particular external tubular membrane unit for MBR. More specifically it was evaluated whether higher stable flux levels could compensate the higher energy consumption, typical for external membrane systems. Both (1) treatment performance and (2) possible operational drawbacks were tested on a 5 m3/h activated sludge pilot-scale. The membrane bioreactor was tested in parallel with a conventional activated sludge system.

  17. IO Rotation Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    During its 1979 flyby, Voyager 2 observed Io only from a distance. However, the volcanic activity discovered by Voyager 1 months earlier was readily visible. This sequence of nine color images was collected using the Blue, Green and Orange filters from about 1.2 million kilometers. A 2.5 hour period is covered during which Io rotates 7 degrees.

    Rotating into view over the limb of Io are the plumes of the volcanoes Amirani (top) and Maui (lower). These plumes are very distinct against the black sky because they are being illuminated from behind. Notice that as Io rotates, the proportion of Io which is sunlit decreases greatly. This changing phase angle is because Io is moving between the spacecraft and the Sun.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1985.

  18. Chiral rotational spectroscopy

    NASA Astrophysics Data System (ADS)

    Cameron, Robert P.; Götte, Jörg B.; Barnett, Stephen M.

    2016-09-01

    We introduce chiral rotational spectroscopy, a technique that enables the determination of the orientated optical activity pseudotensor components BX X, BY Y, and BZ Z of chiral molecules, in a manner that reveals the enantiomeric constitution of a sample and provides an incisive signal even for a racemate. Chiral rotational spectroscopy could find particular use in the analysis of molecules that are chiral solely by virtue of their isotopic constitution and molecules with multiple chiral centers. A basic design for a chiral rotational spectrometer together with a model of its functionality is given. Our proposed technique offers the more familiar polarizability components αX X, αY Y, and αZ Z as by-products, which could see it find use even for achiral molecules.

  19. [Standardization of measurement of catalytic activity concentration of enzymes--current situation regarding the external quality assessment program provided by the Japan Medical Association].

    PubMed

    Maekawa, Masato

    2010-01-01

    Measurement of the catalytic activity concentration of enzymes has been standardized using a traceability chain, consisting a reference measurement system for enzyme catalytic activity and reference standard-JSCC enzyme. The Japan Medical Association (JMA) has provided an external quality assessment (EQA) survey program for clinical laboratory testing. More than 3,100 clinical laboratories participated in 2008. The EQA program indicated that standardization of the measurement of the catalytic activity concentration of enzymes has been completed for AST, ALT, LD, ALP, gammaGT, and CK in more than 90% laboratories, and for Amy and ChE in nearly 80% of laboratories. Because such a large survey program must use artificial specimens, a matrix effect cannot be avoided, especially in dry chemistry. However, the bias produced by a matrix effect usually has a predictable tendency: it can be corrected. Next, after standardization of the measurement of the catalytic activity concentration of enzymes, we should develop and use common reference intervals. On completing the standardization, we can make standard medical decisions using reference measurement systems and rules.

  20. Hip rotation range of motion in sitting and prone positions in healthy Japanese adults

    PubMed Central

    Han, Heonsoo; Kubo, Akira; Kurosawa, Kazuo; Maruichi, Shizuka; Maruyama, Hitoshi

    2015-01-01

    [Purpose] The aim of this study was to elucidate the difference in hip external and internal rotation ranges of motion (ROM) between the prone and sitting positions. [Subjects] The subjects included 151 students. [Methods] Hip rotational ROM was measured with the subjects in the prone and sitting positions. Two-way repeated measures analysis of variance (ANOVA) was used to analyze ipsilateral hip rotation ROM in the prone and sitting positions in males and females. The total ipsilateral hip rotation ROM was calculated by adding the measured values for external and internal rotations. [Results] Ipsilateral hip rotation ROM revealed significant differences between two positions for both left and right internal and external rotations. Hip rotation ROM was significantly higher in the prone position than in the sitting position. Hip rotation ROM significantly differed between the men and women. Hip external rotation ROM was significantly higher in both positions in men; conversely, hip internal rotation ROM was significantly higher in both positions in women. [Conclusion] Hip rotation ROM significantly differed between the sexes and between the sitting and prone positions. Total ipsilateral hip rotation ROM, total angle of external rotation, and total angle of internal rotation of the left and right hips greatly varied, suggesting that hip joint rotational ROM is widely distributed. PMID:25729186

  1. Guide for rotating sucker rods

    SciTech Connect

    Harrel, R.D.

    1986-11-04

    This patent describes an improved guide for use in a string of sucker rods rotated in a tubing string in a borehole, the sucker rods having threaded male ends, the guide comprising: an elongated upright solid cylindrical coupling body of external diameter less than the internal diameter of tubing in which it is to be used; a pair of spaced apart axle holders positioned in three recess; an axle received in each recess in the coupling body, the axis of each axle being parallel and spaced from the body longitudinal axis; a roller rotatably received on each axle, the periphery of each roller extending exteriorly of the external cylindrical surface of the coupling body; and means to retain each of the holders in the coupling body recess.

  2. [Contact sensitization to external agents].

    PubMed

    Erdmann, S M; Merk, H-F

    2003-04-01

    The following review describes contact sensitization to topically applied medications--especially topical dermatological agents--and to external agents in the broadest sense. Particularly skin care products constitute a special source for sensitization due to their widespread use. Especially fragrances and preservatives in cosmetics play an important global role in eliciting contact allergies. Because of the extremely broad spectrum covered by the active and adjuvant ingredients contained in external agents, the following discussion focuses on specific substance groups.

  3. Time-Referenced Effects of an Internal vs. External Focus of Attention on Muscular Activity and Compensatory Variability

    PubMed Central

    Hossner, Ernst-Joachim; Ehrlenspiel, Felix

    2010-01-01

    The paralysis-by-analysis phenomenon, i.e., attending to the execution of one's movement impairs performance, has gathered a lot of attention over recent years (see Wulf, 2007, for a review). Explanations of this phenomenon, e.g., the hypotheses of constrained action (Wulf et al., 2001) or of step-by-step execution (Masters, 1992; Beilock et al., 2002), however, do not refer to the level of underlying mechanisms on the level of sensorimotor control. For this purpose, a “nodal-point hypothesis” is presented here with the core assumption that skilled motor behavior is internally based on sensorimotor chains of nodal points, that attending to intermediate nodal points leads to a muscular re-freezing of the motor system at exactly and exclusively these points in time, and that this re-freezing is accompanied by the disruption of compensatory processes, resulting in an overall decrease of motor performance. Two experiments, on lever sequencing and basketball free throws, respectively, are reported that successfully tested these time-referenced predictions, i.e., showing that muscular activity is selectively increased and compensatory variability selectively decreased at movement-related nodal points if these points are in the focus of attention. PMID:21833285

  4. Time-Referenced Effects of an Internal vs. External Focus of Attention on Muscular Activity and Compensatory Variability.

    PubMed

    Hossner, Ernst-Joachim; Ehrlenspiel, Felix

    2010-01-01

    The paralysis-by-analysis phenomenon, i.e., attending to the execution of one's movement impairs performance, has gathered a lot of attention over recent years (see Wulf, 2007, for a review). Explanations of this phenomenon, e.g., the hypotheses of constrained action (Wulf et al., 2001) or of step-by-step execution (Masters, 1992; Beilock et al., 2002), however, do not refer to the level of underlying mechanisms on the level of sensorimotor control. For this purpose, a "nodal-point hypothesis" is presented here with the core assumption that skilled motor behavior is internally based on sensorimotor chains of nodal points, that attending to intermediate nodal points leads to a muscular re-freezing of the motor system at exactly and exclusively these points in time, and that this re-freezing is accompanied by the disruption of compensatory processes, resulting in an overall decrease of motor performance. Two experiments, on lever sequencing and basketball free throws, respectively, are reported that successfully tested these time-referenced predictions, i.e., showing that muscular activity is selectively increased and compensatory variability selectively decreased at movement-related nodal points if these points are in the focus of attention.

  5. New spatial cognition tests for mice: passive place avoidance on stable and active place avoidance on rotating arenas.

    PubMed

    Cimadevilla, J M; Fenton, A A; Bures, J

    2001-03-15

    Dry arenas are a convenient tool for assessing the spatial navigation abilities of rodents. In this paper, mice must avoid a punished sector of a dry arena from which they are expelled by a puff of compressed air. The position of the punished sector is defined relative to the coordinate system of the room. In a stable environment the mice can use both extramaze and intramaze landmarks to orient themselves accurately. However, when the shock area is defined by extramaze landmarks, continuous rotation of the arena at 1 rpm makes it impossible to solve the avoidance task using arena-based cues or idiothesis. The avoidance can only be solved by paying attention to extramaze cues. Our protocol tested spatial abilities on stable and rotating arenas. The acquisition of the task was manifested under both conditions by a significant improvement of performance within the first session (short-term memory component) and at the beginning of the 24-h delayed second session (long-term memory component).

  6. Anatomical glenohumeral internal rotation deficit and symmetric rotational strength in male and female young beach volleyball players.

    PubMed

    Saccol, Michele Forgiarini; Almeida, Gabriel Peixoto Leão; de Souza, Vivian Lima

    2016-08-01

    Beach volleyball is a sport with a high demand of shoulder structures that may lead to adaptations in range of motion (ROM) and strength like in other overhead sports. Despite of these possible alterations, no study evaluated the shoulder adaptations in young beach volleyball athletes. The aim of this study was to compare the bilateral ROM and rotation strength in the shoulders of young beach volleyball players. Goniometric passive shoulder ROM of motion and isometric rotational strength were evaluated in 19 male and 14 female asymptomatic athletes. External and internal ROM, total rotation motion, glenohumeral internal rotation deficit (GIRD), external rotation and internal rotation strength, bilateral deficits and external rotation to internal rotation ratio were measured. The statistical analysis included paired Student's t-test and analysis of variance with repeated measures. Significantly lower dominant GIRD was found in both groups (p<0.05), but only 6 athletes presented pathological GIRD. For strength variables, no significant differences for external or internal rotation were evident. Young beach volleyball athletes present symmetric rotational strength and shoulder ROM rotational adaptations that can be considered as anatomical. These results indicate that young practitioners of beach volleyball are subject to moderate adaptations compared to those reported for other overhead sports.

  7. The External Degree.

    ERIC Educational Resources Information Center

    Houle, Cyril O.

    This book examines the external degree in relation to the extremes of attitudes, myths, and data. Emphasis is placed on the emergence of the American external degree, foreign external-degree programs, the purpose of the external degree, the current scene, institutional issues, and problems of general policy. (MJM)

  8. The influences of impact interface, muscle activity, and knee angle on impact forces and tibial and femoral accelerations occurring after external impacts.

    PubMed

    Potthast, Wolfgang; Brüggemann, Gert-Peter; Lundberg, Arne; Arndt, Anton

    2010-02-01

    The purpose of this study was to quantify relative contributions of impact interface, muscle activity, and knee angle to the magnitudes of tibial and femoral accelerations occurring after external impacts. Impacts were initiated with a pneumatically driven impacter under the heels of four volunteers. Impact forces were quantified with a force sensor. Segmental accelerations were measured with bone mounted accelerometers. Experimental interventions were hard and soft shock interfaces, different knee angles (0 degrees, 20 degrees, 40 degrees knee flexion), and muscular preactivation (0%, 30%, 60% of maximal voluntary contraction) of gastrocnemii, hamstrings, and quadriceps. Greater knee flexion led to lower impact forces and higher tibial accelerations. Increased muscular activation led to higher forces and lower tibial accelerations. The softer of the two shock interfaces under study reduced both parameters. The effects on accelerations and forces through the activation and knee angle changes were greater than the effect of interface variations. The hardness of the two shock interfaces explained less than 10% of the variance of accelerations and impact forces, whereas knee angle changes explained 25-29%, and preactivation changes explained 35-48% of the variances. It can be concluded that muscle force and knee joint angle have greater effects in comparison with interface hardness on the severity of shocks on the lower leg.

  9. In-line rotating capacitive torque sensor

    DOEpatents

    Kronberg, James W.

    1991-01-01

    A method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotating portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources.

  10. Effects of preincubation of eggs and activation medium on the percentage of eyed embryos in ide (Leuciscus idus), an externally fertilizing fish.

    PubMed

    Siddique, Mohammad Abdul Momin; Linhart, Otomar; Krejszeff, Sławomir; Żarski, Daniel; Król, Jarosław; Butts, Ian Anthony Ernest

    2016-03-15

    Standardization of fertilization protocols is crucial for improving reproductive techniques for externally fertilizing fish in captive breeding. Therefore, the objectives of this study were to determine the effects of preincubation of eggs and activation medium on the percentage of eyed embryos for ide (Leuciscus idus). Pooled eggs from five females were preincubated in three different activating media for 0, 30, 60, 90, and 120 seconds and then fertilized by pooled sperm from five males. At the eyed-egg stage, the percentage of viable embryos was later calculated. Results showed that preincubation time was significant for the freshwater activation medium (P < 0.001), such that the percentage of eyed embryos declined across the preincubation time gradient. Additionally, there was an effect on the percentage of eyed embryos when eggs were incubated with Woynarovich solution (P < 0.001), such that a decline was detected at 90 seconds, whereas no effect was detected for the saline water medium. Activating medium had a significant effect on the percentage of eyed embryos for each preincubation time (P < 0.05). More precisely, freshwater produced the lowest percentage of eyed embryos at all preincubation times (ranged from 1.9% at 120 seconds to 43.6% at 0 seconds), whereas saline water and Woynarovich solution produced the highest percentage of eyed embryos at 0 seconds and 30 seconds before incubation. Woynarovich solution produced the highest percentage of eyed embryos at 60 seconds (65.26%), whereas saline water produced the highest percentage at 90 seconds (68.37%). No difference was detected between saline water and Woynarovich solution at 120 seconds. Examination of sperm traits showed no impact of activating medium on computer assisted sperm analysis parameters. Together, these results suggest that saline water or Woynarovich solution improve fertilization rate in ide during IVF; thus, these media are useful for standardizing fertilization protocols and

  11. Asymmetric error field interaction with rotating conducting walls

    SciTech Connect

    Paz-Soldan, C.; Brookhart, M. I.; Hegna, C. C.; Forest, C. B.

    2012-07-15

    The interaction of error fields with a system of differentially rotating conducting walls is studied analytically and compared to experimental data. Wall rotation causes eddy currents to persist indefinitely, attenuating and rotating the original error field. Superposition of error fields from external coils and plasma currents are found to break the symmetry in wall rotation direction. The vacuum and plasma eigenmodes are modified by wall rotation, with the error field penetration time decreased and the kink instability stabilized, respectively. Wall rotation is also predicted to reduce error field amplification by the marginally stable plasma.

  12. Distinctive translational and self-rotational motion of lymphoma cells in an optically induced non-rotational alternating current electric field.

    PubMed

    Liang, Wenfeng; Zhang, Ke; Yang, Xieliu; Liu, Lianqing; Yu, Haibo; Zhang, Weijing

    2015-01-01

    In this paper, the translational motion and self-rotational behaviors of the Raji cells, a type of B-cell lymphoma cell, in an optically induced, non-rotational, electric field have been characterized by utilizing a digitally programmable and optically activated microfluidics chip with the assistance of an externally applied AC bias potential. The crossover frequency spectrum of the Raji cells was studied by observing the different linear translation responses of these cells to the positive and negative optically induced dielectrophoresis force generated by a projected light pattern. This digitally projected spot served as the virtual electrode to generate an axisymmetric and non-uniform electric field. Then, the membrane capacitance of the Raji cells could be directly measured. Furthermore, Raji cells under this condition also exhibited a self-rotation behavior. The repeatable and controlled self-rotation speeds of the Raji cells to the externally applied frequency and voltage were systematically investigated and characterized via computer-vision algorithms. The self-rotational speed of the Raji cells reached a maximum value at 60 kHz and demonstrated a quadratic relationship with respect to the applied voltage. Furthermore, optically projected patterns of four orthogonal electrodes were also employed as the virtual electrodes to manipulate the Raji cells. These results demonstrated that Raji cells located at the center of the four electrode pattern could not be self-rotated. Instead any Raji cells that deviated from this center area would also self-rotate. Most importantly, the Raji cells did not exhibit the self-rotational behavior after translating and rotating with respect to the center of any two adjacent electrodes. The spatial distributions of the electric field generated by the optically projected spot and the pattern of four electrodes were also modeled using a finite element numerical simulation. These simulations validated that the electric field

  13. Distinctive translational and self-rotational motion of lymphoma cells in an optically induced non-rotational alternating current electric field

    PubMed Central

    Zhang, Ke; Yang, Xieliu; Liu, Lianqing; Yu, Haibo; Zhang, Weijing

    2015-01-01

    In this paper, the translational motion and self-rotational behaviors of the Raji cells, a type of B-cell lymphoma cell, in an optically induced, non-rotational, electric field have been characterized by utilizing a digitally programmable and optically activated microfluidics chip with the assistance of an externally applied AC bias potential. The crossover frequency spectrum of the Raji cells was studied by observing the different linear translation responses of these cells to the positive and negative optically induced dielectrophoresis force generated by a projected light pattern. This digitally projected spot served as the virtual electrode to generate an axisymmetric and non-uniform electric field. Then, the membrane capacitance of the Raji cells could be directly measured. Furthermore, Raji cells under this condition also exhibited a self-rotation behavior. The repeatable and controlled self-rotation speeds of the Raji cells to the externally applied frequency and voltage were systematically investigated and characterized via computer-vision algorithms. The self-rotational speed of the Raji cells reached a maximum value at 60 kHz and demonstrated a quadratic relationship with respect to the applied voltage. Furthermore, optically projected patterns of four orthogonal electrodes were also employed as the virtual electrodes to manipulate the Raji cells. These results demonstrated that Raji cells located at the center of the four electrode pattern could not be self-rotated. Instead any Raji cells that deviated from this center area would also self-rotate. Most importantly, the Raji cells did not exhibit the self-rotational behavior after translating and rotating with respect to the center of any two adjacent electrodes. The spatial distributions of the electric field generated by the optically projected spot and the pattern of four electrodes were also modeled using a finite element numerical simulation. These simulations validated that the electric field

  14. X-RAY, FUV, AND UV OBSERVATIONS OF {alpha} CENTAURI B: DETERMINATION OF LONG-TERM MAGNETIC ACTIVITY CYCLE AND ROTATION PERIOD

    SciTech Connect

    DeWarf, L. E.; Guinan, E. F.; Datin, K. M.

    2010-10-10

    cycle of P{sub cycle} = 8.84 {+-} 0.4 years. In addition, analysis of the short-term rotational modulation of mean light due to the effects of magnetically active regions has yielded a well-determined rotation period of P{sub rotation} = 36.2 {+-} 1.4 days. {alpha} Cen B is the only old main-sequence K star with a reliably determined age and rotation period, and for early K stars, as in the case of the Sun for G2 V stars, is an important calibrator for stellar age/rotation/activity relations.

  15. Measurement of Small Optical Polarization Rotations

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2009-01-01

    When data with and without an optically active sample are acquired simultaneously while one manually rotates the analyser, the graph of the first signal versus the second one is an ellipse whose shape shows the phase shift between the two signals; this shift is twice the optical rotation. There is no need to measure the rotation of the analyser or…

  16. Motor Processes in Children's Mental Rotation

    ERIC Educational Resources Information Center

    Frick, Andrea; Daum, Moritz M.; Walser, Simone; Mast, Fred W.

    2009-01-01

    Previous studies with adult human participants revealed that motor activities can influence mental rotation of body parts and abstract shapes. In this study, we investigated the influence of a rotational hand movement on mental rotation performance from a developmental perspective. Children at the age of 5, 8, and 11 years and adults performed a…

  17. Rotation Manager Pro Version 1.0b1

    SciTech Connect

    Moore, Thomas L.; Scotese, Christopher

    2002-02-01

    The Rotation Manager Pro Package maintains databases of instructions to replicate plate tectonic movements. The instructions are in the standard of tectonic plate rotations, including plate identification and location and angle of the rotation pole. Each database is accompanied by various metadata, including information about each rotation pole and the database itself. The package provides a range of tools to actively manage the database using methods specifically required for rotations: rotation pole addition and subtraction, viewing of a rotation chain through the rotation hierarchy, and the rotation of data points.

  18. Rotation Manager Pro Version 1.0b1

    2002-02-01

    The Rotation Manager Pro Package maintains databases of instructions to replicate plate tectonic movements. The instructions are in the standard of tectonic plate rotations, including plate identification and location and angle of the rotation pole. Each database is accompanied by various metadata, including information about each rotation pole and the database itself. The package provides a range of tools to actively manage the database using methods specifically required for rotations: rotation pole addition and subtraction,more » viewing of a rotation chain through the rotation hierarchy, and the rotation of data points.« less

  19. Assessing the Internal and External Validity of Mobile Health Physical Activity Promotion Interventions: A Systematic Literature Review Using the RE-AIM Framework

    PubMed Central

    Zoellner, Jamie; Berrey, Leanna M; Alexander, Ramine; Fanning, Jason; Hill, Jennie L; Estabrooks, Paul A

    2013-01-01

    Background Mobile health (mHealth) interventions are effective in promoting physical activity (PA); however, the degree to which external validity indicators are reported is unclear. Objective The purpose of this systematic review was to use the RE-AIM (reach, effectiveness, adoption, implementation, and maintenance) framework to determine the extent to which mHealth intervention research for promoting PA reports on factors that inform generalizability across settings and populations and to provide recommendations for investigators planning to conduct this type of research. Methods Twenty articles reflecting 15 trials published between 2000 and 2012 were identified through a systematic review process (ie, queries of three online databases and reference lists of eligible articles) and met inclusion criteria (ie, implementation of mobile technologies, target physical activity, and provide original data). Two researchers coded each article using a validated RE-AIM data extraction tool (reach, efficacy/effectiveness, adoption, implementation, maintenance). Two members of the study team independently abstracted information from each article (inter-rater reliability >90%) and group meetings were used to gain consensus on discrepancies. Results The majority of studies were randomized controlled trials (n=14). The average reporting across RE-AIM indicators varied by dimension (reach=53.3%, 2.67/5; effectiveness/efficacy=60.0%, 2.4/4; adoption=11.1%, 0.7/6; implementation=24.4%, 0.7/3; maintenance=0%, 0/3). While most studies described changes in the primary outcome (effectiveness), few addressed the representativeness of participants (reach) or settings (adoption) and few reported on issues related to maintenance and degree of implementation fidelity. Conclusions This review suggests that more focus is needed on research designs that highlight and report on both internal and external validity indicators. Specific recommendations are provided to encourage future m

  20. Asymmetric Hip Rotation in Professional Baseball Pitchers

    PubMed Central

    McCulloch, Patrick C.; Patel, Jayesh K.; Ramkumar, Prem N.; Noble, Philip C.; Lintner, David M.

    2014-01-01

    Background: There is a renewed interest in examining the association between hip range of motion and injury in athletes, and the data on baseball players are conflicting. Understanding whether asymmetrical hip rotation is a normal adaptation or a risk factor for injury will help therapists, trainers, and physicians develop rehabilitation programs to improve kinetic energy transfer and prevent injury. As our knowledge of hip pathology among baseball pitchers improves, establishing baselines for hip motion is critical in the further assessment of injury. Hypothesis: Because of the repetitive nature of throwing sports and the adaptive changes documented in the shoulder, elite baseball pitchers would have characteristic patterns of hip internal and external rotations on their dominant throwing side (stance) and their nondominant side (stride) in extension. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Computer software was used to measure passive internal and external rotations on digital photographs of 111 professional baseball pitchers. Results: In right-handed pitchers, there was significantly more internal rotation in the stance hip than the stride hip (32.2° ± 8.2° vs 30.8° ± 8.4°; P = .0349) and significantly more external rotation in the stride hip than the stance hip (36.3° ± 7.7° vs 30.8° ± 9.7°; P < .0001). While the mean difference in external rotation was 4.7°, 32% of the subjects had a >10° increase in external rotation on the stride hip relative to the stance hip. This population was statistically different from the remaining group for older age (P = .0053), lower body mass index (P = .0379), and more years in professional baseball (P = .0328). In the smaller number of left-handed pitchers, side-to-side differences in hip rotation were found but were not statistically significant. Conclusion: Pitchers showed more internal rotation on their stance hip and more external rotation on their stride hip. Although the mean

  1. Singing-related neural activity distinguishes two putative pallidal cell types in the songbird basal ganglia: comparison to the primate internal and external pallidal segments

    PubMed Central

    Goldberg, Jesse H.; Adler, Avital; Bergman, Hagai; Fee, Michale S.

    2010-01-01

    The songbird area X is a basal ganglia homologue that contains two pallidal cell types—local neurons that project within the basal ganglia and output neurons that project to the thalamus. Based on these projections, it has been proposed that these classes are structurally homologous to the primate external (GPe) and internal (GPi) pallidal segments. To test the hypothesis that the two area X pallidal types are functionally homologous to GPe and GPi neurons, we recorded from neurons in area X of singing juvenile male zebra finches, and directly compare their firing patterns to neurons recorded in the primate pallidus. In area X, we find two cell classes that exhibited high firing (HF) rates (>60Hz) characteristic of pallidal neurons. HF-1 neurons, like most GPe neurons we examined, exhibited large firing rate modulations, including bursts and long pauses. In contrast, HF-2 neurons, like GPi neurons, discharged continuously without bursts or long pauses. To test if HF-2 neurons were the output neurons that project to the thalamus, we next recorded directly from pallidal axon terminals in thalamic nucleus DLM, and found that all terminals exhibited singing-related firing patterns indistinguishable from HF-2 neurons. Our data show that singing-related neural activity distinguishes two putative pallidal cell types in area X: thalamus-projecting neurons that exhibit activity similar to the primate GPi, and non-thalamus-projecting neurons that exhibit activity similar to the primate GPe. These results suggest that song learning in birds and motor learning in mammals employ conserved basal ganglia signaling strategies. PMID:20484651

  2. Maximising somersault rotation in tumbling.

    PubMed

    King, M A Mark A; Yeadon, M R Maurice R

    2004-04-01

    Performing complex somersaulting skills during the flight phase of tumbling requires the generation of linear and angular momenta during the approach and takeoff phases. This paper investigates how approach characteristics and takeoff technique affect performance with a view to maximising somersault rotation in tumbling. A five-segment planar simulation model, customised to an elite gymnast, was used to produce a simulation which closely matched a recorded performance of a double layout somersault by the elite gymnast. Three optimisations were carried out to maximise somersault rotation with different sets of initial conditions. Using the same initial linear and angular momentum as the double layout somersault and varying the joint torque activation timings allowed a double straight somersault to be performed with 19% more rotation potential than the actual performance. Increasing the approach velocity to a realistic maximum of 7 ms(-1) resulted in a 42% reduction in rotation potential when the activation timings were unchanged but allowed a triple layout somersault to be performed with an increase of 31% in rotation potential when activation timings were re-optimised. Increasing also the initial angular momentum to a realistic maximum resulted in a 4% reduction in rotation potential when the activation timings were unchanged but allowed a triple straight somersault to be performed with a further increase of 9% in rotation potential when activation timings were re-optimised. It is concluded that the limiting factor to maximising somersault rotation is the ability to generate high linear and angular velocities during the approach phase coupled with the ability to adopt consonant activation timings during the takeoff phase. PMID:14996558

  3. Nonbridging external fixation of distal radius fractures.

    PubMed

    Eichenbaum, Matthew D; Shin, Eon K

    2010-08-01

    Surgical management of distal radius fractures continues to evolve because of their high incidence in an increasingly active elderly population. Traditional radiocarpal external fixation relies on ligamentotaxis for fracture reduction but has several drawbacks. Nonbridging external fixation has evolved to provide early wrist mobility in the setting of anatomic fracture reduction. Several studies of the nonbridging technique have demonstrated satisfactory results in isolated nonbridging external fixation series and in comparison with traditional spanning external fixation. Nonbridging external fixation for surgical treatment of distal radius fractures can be technically demanding and requires at least 1 cm of intact volar cortex in the distal fracture fragment for successful implementation.

  4. Assigning the Vibration-Rotation Spectra Using the Lww Program Package

    NASA Astrophysics Data System (ADS)

    Lodyga, Wieslaw; Kreglewski, Marek

    2016-06-01

    The LWW program package is based on traditional methods used in assigning rotationally resolved IR molecular spectra. The Loomis-Wood diagrams, which are used to visualize spectral branches and facilitate their identification, are combined with the power of interactive lower state combination difference (LSCD) checking, which provides immediate verification of correct assignments of quantum numbers to spectral lines. The traditional Giessen/Cologne type Loomis-Wood algorithm is also implemented. Predictions of vibration-rotation wavenumbers are calculated from a table of vibration-rotation energies, which can be imported from any external fitting program. Program includes many additional tools like simulation of a spectrum from a catalog file (list of transitions with intensities), build-up of a vibration-rotation band from individual branches and simultaneous displaying of two IR spectra - active one used for assignments and a reference one, both with full link to their peak-list files. Importing energies as well as exporting assigned data for fitting in an external program is made easy and flexible by a user-programmed import/export interface, which facilitates iterative refining of energy levels and gives a possibility of using directly exact vibration-rotation energies. Program is available in tree versions: for symmetric top, asymmetric top and molecules with large amplitude motions. The program is designed for the Windows operating systems and is available with full documentation on www.lww.amu.edu.pl .

  5. Acute Effects of Foot Rotation in Healthy Adults during Running on Knee Moments and Lateral-Medial Shear Force

    PubMed Central

    Valenzuela, Kevin A.; Lynn, Scott K.; Noffal, Guillermo J.; Brown, Lee E.

    2016-01-01

    As runners age, the likelihood of developing osteoarthritis (OA) significantly increases as 10% of people 55+ have symptomatic knee OA while 70% of people 65+ have radiographic signs of knee OA. The lateral-medial shear force (LMF) and knee adduction moment (KAM) during gait have been associated with cartilage loading which can lead to OA. Foot rotation during gait has been shown to alter the LMF and KAM, however it has not been investigated in running. The purpose of this study was to investigate changes in the KAM and LMF with foot rotation during running. Twenty participants volunteered and performed five running trials in three randomized conditions (normal foot position [NORM], external rotation [EXT], and internal rotation [INT]) at a running speed of 3.35m·s-1 on a 20 meter runway. Kinematic and kinetic data were gathered using a 9-camera motion capture system and a force plate, respectively. Repeated measures ANOVAs determined differences between conditions. The KAM and LMF were lower in both EXT and INT conditions compared to the NORM, but there were no differences between EXT and INT conditions. The decreases in KAM and LMF in the EXT condition were expected and concur with past research in other activities. The reductions in the INT condition were unexpected and contradict the literature. This may indicate that participants are making mechanical compensations at other joints to reduce the KAM and LMF in this abnormal internal foot rotation condition. Key points External rotation of the foot during running reduced the loads on the medial compartment of the knee Internal rotation of the foot also reduced the medial loads, but is a more unnatural intervention External and internal rotation reduced the shear forces on the knee, which may help slow the degeneration of knee joint cartilage PMID:26957926

  6. Starspot evolution, differential rotation, and magnetic cycles in the chromospherically active binaries lambda andromedae, sigma Geminorum, II Pegasi, and V711 Tauri

    NASA Technical Reports Server (NTRS)

    Henry, Gregory W.; Eaton, Joel A.; Hamer, Jamesia; Hall, Douglas S.

    1995-01-01

    We have analyzed 15-19 yr of photoelectric photometry, obtained manually and with automated telescopes, of the chromospherically active binaries lambda And, sigma Gem, II Peg, and V711 Tau. These observations let us identify individual dark starspots on the stellar surfaces from periodic dimming of the starlight, follow the evolution of these spots, and search for long-term cyclic changes in the properties of these starspots that might reveal magnetic cycles analogous to the Sun's 11 yr sunspot cycle. We developed a computer code to fit a simple two-spot model to our observed light curves that allows us to extract the most easily determinable and most reliable spot parameters from the light curves, i.e., spot longitudes and radii. We then used these measured properties to identify individual spots and to chart their life histories by constructing migration and amplitude curves. We identified and followed 11 spots in lambda And, 16 in sigma Gem, 12 in II Peg, and 15 in V711 Tau. Lifetimes of individual spots ranged from a few months to longer than 6 yr. Differential rotation coefficients, estimated from the observed range of spot rotation periods for each star and defined by equation (2), were 0.04 for lambda And, 0.038 for sigma Gem, 0.005 for II Peg, and 0.006 for V711 Tau, versus 0.19 for the Sun. We searched for cyclic changes in mean brightness, B-V color index, and spot rotation period as evidence for long-term cycles. Of these, long-term variability in mean brightness appears to offer the best evidence for such cycles in these four stars. Cycles of 11.1 yr for lambda And, 8.5 yr for sigma Gem, 11 yr for II Peg, and 16 yr V711 Tau are implied by these mean brightness changes. Cyclic changes in spot rotation period were found in lambda And and possibly II Peg. Errors in B-V were too large for any long-term changes to be detectable.

  7. Automated External Defibrillator

    MedlinePlus

    ... from the NHLBI on Twitter. What Is an Automated External Defibrillator? An automated external defibrillator (AED) is a portable device that ... Institutes of Health Department of Health and Human Services USA.gov

  8. Low edge safety factor operation and passive disruption avoidance in current carrying plasmas by the addition of stellarator rotational transform

    NASA Astrophysics Data System (ADS)

    Pandya, M. D.; ArchMiller, M. C.; Cianciosa, M. R.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Hebert, J. D.; Herfindal, J. L.; Knowlton, S. F.; Ma, X.; Massidda, S.; Maurer, D. A.; Roberds, N. A.; Traverso, P. J.

    2015-11-01

    Low edge safety factor operation at a value less than two ( q (a )=1 /ι̷tot(a )<2 ) is routine on the Compact Toroidal Hybrid device with the addition of sufficient external rotational transform. Presently, the operational space of this current carrying stellarator extends down to q (a )=1.2 without significant n = 1 kink mode activity after the initial plasma current rise phase of the discharge. The disruption dynamics of these low edge safety factor plasmas depend upon the fraction of helical field rotational transform from external stellarator coils to that generated by the plasma current. We observe that with approximately 10% of the total rotational transform supplied by the stellarator coils, low edge q disruptions are passively suppressed and avoided even though q(a) < 2. When the plasma does disrupt, the instability precursors measured and implicated as the cause are internal tearing modes with poloidal, m, and toroidal, n, helical mode numbers of m /n =3 /2 and 4/3 observed on external magnetic sensors and m /n =1 /1 activity observed on core soft x-ray emissivity measurements. Even though the edge safety factor passes through and becomes much less than q(a) < 2, external n = 1 kink mode activity does not appear to play a significant role in the disruption phenomenology observed.

  9. External tank project new technology plan. [development of space shuttle external tank system

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A production plan for the space shuttle external tank configuration is presented. The subjects discussed are: (1) the thermal protection system, (2) thermal coating application techniques, (3) manufacturing and tooling, (4) propulsion system configurations and components, (5) low temperature rotating and sliding joint seals, (6) lightning protection, and (7) nondestructive testing technology.

  10. An off-axis rotating atom trap.

    PubMed

    Wu, J; Moscatelli, F; Oh, E

    2006-06-12

    We present a novel configuration of a magneto-optical trap for cold atoms. The trap is very simple in design, employing only a small permanent magnet and an external Helmholtz bias coil. The trap's principal advantage is that the entire volume of the overlapping laser beams can be used for atom guiding and manipulation. An especially interesting effect is the rotation of the trapped atoms in circular motion as the permanent magnet is rotated. Clouds containing on the order of 2*10(6) atoms are rotated up to 60Hz forming a 5 mm diameter ring. This rotation can potentially be used in studying the behavior of cold atoms in 2-dimensional potential as well as applications for rotational sensors. We also present a classical theoretical model to simulate the experiment.

  11. External artery heat pipe

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)

    1989-01-01

    An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

  12. Earth rotation and geodynamics

    NASA Astrophysics Data System (ADS)

    Bogusz, Janusz; Brzezinski, Aleksander; Kosek, Wieslaw; Nastula, Jolanta

    2015-12-01

    This paper presents the summary of research activities carried out in Poland in 2011-2014 in the field of Earth rotation and geodynamics by several Polish research institutions. It contains a summary of works on Earth rotation, including evaluation and prediction of its parameters and analysis of the related excitation data as well as research on associated geodynamic phenomena such as geocentre motion, global sea level change and hydrological processes. The second part of the paper deals with monitoring of geodynamic phenomena. It contains analysis of geodynamic networks of local, and regional scale using space (GNSS and SLR) techniques, Earth tides monitoring with gravimeters and water-tube hydrostatic clinometer, and the determination of secular variation of the Earth' magnetic field.

  13. Rotator Cuff Tears

    MedlinePlus

    ... doctors because of a rotator cuff problem. A torn rotator cuff will weaken your shoulder. This means ... or more of the rotator cuff tendons is torn, the tendon no longer fully attaches to the ...

  14. Influence of changes in external potassium and chloride ions on membrane potential and intracellular potassium ion activity in rabbit ventricular muscle.

    PubMed

    Fozzard, H A; Lee, C O

    1976-04-01

    1. The membrane responses of rabbit papillary muscles to rapid changes in [K](o) and [Cl](o) were measured with open-tipped micropipettes and with closed micropipettes made from K-selective glass.2. The muscle cells behaved primarily as a K electrode, and responses to changes in [K](o) with constant [Cl](o) or with constant [K](o) x [Cl](o) were substantially the same.3. When [Cl](o) was changed at a constant [K](o) the membrane potentials changed rapidly and symmetrically by a small value and remained constant for 30 min.4. Measurement of potential with K(+)-selective micro-electrodes in these experiments showed no change in intracellular K activity. In addition to permitting calculation of K permeability, these measurements reassured us that the K(+)-selective electrodes were well insulated and not influenced by electrical shunts at the impalement site.5. Although the membrane response to changes in [Cl](o) was small, it was possible to calculate that the permeability ratio (P(Cl)/P(K)), was 0.11. The Cl and K conductances were about 0.015 mmho/cm(2) and 0.09 mmho/cm(2) respectively, resulting in a conductance ratio (g(Cl)/g(K)) of about 0.17.6. The time course of depolarization by increase in [K](o) was rapid (half-time 5 sec), but repolarization on return to lower [K](o) was much slower (half-time 50 sec). The depolarization time course was easily fitted by the potential change calculated by assuming the need for K diffusion into the extracellular spaces and taking account of the logarithmic relation between membrane potential and [K](o). These calculations did not fit the time course of repolarization, which was slowed in the fashion expected from an inward-rectifying membrane.7. The influence of [K](i) on membrane potential was investigated by changes in tonicity of the external solution. Hypotonic solution produced a change in intracellular K activity close to that produced by ideal water movement. However, in hypertonic solution, intracellular K activity

  15. External combustion engine with improved piston and crankshaft linkage

    SciTech Connect

    Lopez, F.

    1991-03-12

    This patent describes improvement in an external heat engine having a piston mounted for movement between a first position and a second position, means for forcibly moving the piston from the first position to the second position (power stroke), a crankshaft rotatable about a main axis, and means for linking the piston and crankshaft so that linear movement of the piston from the first position to the second position during the power stroke is transformed into rotational movement of the crankshaft, the power stroke corresponding to a first portion of one rotation of the crankshaft about the main axis, the piston moving from the second position to the first position during a second portion of one rotation of the crankshaft (compression stroke). The improvement comprises: means for linking the piston and crankshaft comprises a rotatable member; means connected to the piston for rotatably supporting the rotatable member, the rotatable member being rotatable about a first point and being connected to the crankshaft at a second point offset from the first point, for rotation about the first point in response to rotation of the crankshaft about its main axis, the first point being disposed so that when the piston is in the first position, the first point is substantially aligned with the main axis of the crankshaft during a third portion of one rotation of the crankshaft about the main axis.

  16. Workshop Physics Activity Guide, Module 2: Mechanics II, Momentum, Energy, Rotational and Harmonic Motion, and Chaos (Units 8 - 15)

    NASA Astrophysics Data System (ADS)

    Laws, Priscilla W.

    2004-05-01

    The Workshop Physics Activity Guide is a set of student workbooks designed to serve as the foundation for a two-semester calculus-based introductory physics course. It consists of 28 units that interweave text materials with activities that include prediction, qualitative observation, explanation, equation derivation, mathematical modeling, quantitative experiments, and problem solving. Students use a powerful set of computer tools to record, display, and analyze data, as well as to develop mathematical models of physical phenomena. The design of many of the activities is based on the outcomes of physics education research. The Workshop Physics Activity Guide is supported by an Instructor's Website that: (1) describes the history and philosophy of the Workshop Physics Project; (2) provides advice on how to integrate the Guide into a variety of educational settings; (3) provides information on computer tools (hardware and software) and apparatus; and (4) includes suggested homework assignments for each unit. Log on to the Workshop Physics Project website at http://physics.dickinson.edu/ Workshop Physics is a component of the Physics Suite--a collection of materials created by a group of educational reformers known as the Activity Based Physics Group. The Physics Suite contains a broad array of curricular materials that are based on physics education research, including:

      Understanding Physics, by Cummings, Laws, Redish and Cooney (an introductory textbook based on the best-selling text by Halliday/Resnick/Walker) RealTime Physics Laboratory Modules Physics by Inquiry (intended for use in a workshop setting) Interactive Lecture Demonstration Tutorials in Introductory Physics Activity Based Tutorials (designed primarily for use in recitations)

    • Macroscopic response of particle-reinforced elastomers subjected to prescribed torques or rotations on the particles

      NASA Astrophysics Data System (ADS)

      Siboni, Morteza H.; Ponte Castañeda, Pedro

      2016-06-01

      Particle-reinforced rubbers are composite materials consisting of randomly distributed, stiff fibers/particles in a soft elastomeric material. Since the particles are stiff compared to the embedding rubber, their deformation can be ignored for all practical purposes. However, due to the softness of the rubber, they can undergo rigid body translations and rotations. Constitutive models accounting for the effect of such particle motions on the macroscopic response under prescribed deformations on the boundary have been developed recently. But, in some applications (e.g., magneto-active elastomers), the particles may experience additional torques as a consequence of an externally applied (magnetic) field, which, in turn, can affect the overall rotation of the particles in the rubber, and therefore also the macroscopic response of the composite. This paper is concerned with the development of constitutive models for particle-reinforced elastomers, which are designed to account for externally applied torques on the internally distributed particles, in addition to the externally applied deformation on the boundary of the composite. For this purpose, we propose a new variational framework involving suitably prescribed eigenstresses on the particles. For simplicity, the framework is applied to an elastomer reinforced by aligned, rigid, cylindrical fibers of elliptical cross section, which can undergo finite rotations in the context of a finite-deformation, plane strain problem for the composite. In particular, expressions are derived for the average in-plane rotation of the fibers as a function of the torques that are applied on them, both under vanishing and prescribed strain on the boundary. The results of this work will make possible the development of improved constitutive models for magneto-active elastomers, and other types of smart composite materials that are susceptible to externally applied torques.

    • Voluntary activation deficits of the infraspinatus present as a consequence of pitching-induced fatigue

      PubMed Central

      Gandhi, Jaipal; ElAttrache, Neal S.; Kaufman, Kenton R.; Hurd, Wendy J.

      2014-01-01

      Hypothesis Neuromuscular inhibition of the infraspinatus would be greater and external rotation muscle force would be lower after a simulated game compared with pregame values. Materials and methods The sample included 21 uninjured, asymptomatic high school–aged baseball pitchers. Maximum volitional shoulder external rotation strength was assessed before and after a simulated game with a clinical dynamometer. Voluntary activation of the infraspinatus was assessed during strength testing by a modified burst superimposition technique. Performance-related fatigue was assessed by monitoring pitch velocity, and global fatigue was assessed by subject self-report before and after the game. Statistical testing included paired and independent t tests, with α ≤ 05. Results There was no difference between throwing and non-throwing shoulder external rotation strength (P = .12) or voluntary infraspinatus activation (P = .27) before the game. After the game, voluntary activation was significantly lower in the throwing limb compared with pregame activation levels (P = .01). Lower external rotation strength after the game approached statistical significance (P =.06). Pitch velocity was lower in the final inning compared with first-inning velocity (P = .01), and fatigue was significantly greater after the game (P = .01). Conclusions Voluntary infraspinatus muscle activation is a mechanism contributing to external rotation muscle weakness in the fatigued pitcher. Understanding mechanisms contributing to muscle weakness is necessary to develop effective injury prevention and rehabilitation programs. Treatment techniques that enhance neuromuscular activation may be a useful strategy for enhancing strength in this population. Level of evidence Basic Science Study, Kinesiology Study. PMID:21831667

    • Mapping field spatial distribution patterns of isoproturon-mineralizing activity over a three-year winter wheat/rape seed/barley rotation.

      PubMed

      Hussain, S; Devers-Lamrani, M; Spor, A; Rouard, N; Porcherot, M; Beguet, J; Martin-Laurent, F

      2013-03-01

      The temporal and spatial variability of the activity of soil microorganisms able to mineralize the herbicide isoproturon (IPU) pesticide was investigated over a three-year long crop rotation between 2008 and 2010. Isoproturon mineralization was higher in 2008, when winter wheat was treated with this herbicide, than in 2009 and 2010, when rape seed and barley were treated with different herbicides. Under laboratory conditions, we showed that isoproturon mineralization was not promoted by sulfonylurea herbicide applied on barley crop in 2010. IPU mineralization was shown to be highly variable at the field scale in years 2009 and 2010. Principal component analyses and analyses of similarities revealed that soil pH and equivalent humidity, and to a lesser extent soil organic matter content and cation exchange capacity (CEC) were the main drivers of isoproturon-mineralizing activity variance. Using a rather simple model that yields the rate of isoproturon mineralization as a function of soil pH and equivalent humidity, we explained up to 85% of the variance observed. Mapping field-scale distribution of isoproturon mineralization over the three-year survey indicated higher variability in 2009 and in 2010 as compared to 2008, suggesting that isoproturon treatment applied to winter wheat promoted isoproturon mineralization activity and reduced its spatial variability. Field-scale distribution of isoproturon mineralization showed important similarity to the distribution of soil pH, equivalent humidity and to a lesser extent to soil organic matter and cation exchange capacity (CEC) thereby confirming our model.

    • Mapping field spatial distribution patterns of isoproturon-mineralizing activity over a three-year winter wheat/rape seed/barley rotation.

      PubMed

      Hussain, S; Devers-Lamrani, M; Spor, A; Rouard, N; Porcherot, M; Beguet, J; Martin-Laurent, F

      2013-03-01

      The temporal and spatial variability of the activity of soil microorganisms able to mineralize the herbicide isoproturon (IPU) pesticide was investigated over a three-year long crop rotation between 2008 and 2010. Isoproturon mineralization was higher in 2008, when winter wheat was treated with this herbicide, than in 2009 and 2010, when rape seed and barley were treated with different herbicides. Under laboratory conditions, we showed that isoproturon mineralization was not promoted by sulfonylurea herbicide applied on barley crop in 2010. IPU mineralization was shown to be highly variable at the field scale in years 2009 and 2010. Principal component analyses and analyses of similarities revealed that soil pH and equivalent humidity, and to a lesser extent soil organic matter content and cation exchange capacity (CEC) were the main drivers of isoproturon-mineralizing activity variance. Using a rather simple model that yields the rate of isoproturon mineralization as a function of soil pH and equivalent humidity, we explained up to 85% of the variance observed. Mapping field-scale distribution of isoproturon mineralization over the three-year survey indicated higher variability in 2009 and in 2010 as compared to 2008, suggesting that isoproturon treatment applied to winter wheat promoted isoproturon mineralization activity and reduced its spatial variability. Field-scale distribution of isoproturon mineralization showed important similarity to the distribution of soil pH, equivalent humidity and to a lesser extent to soil organic matter and cation exchange capacity (CEC) thereby confirming our model. PMID:23246724

  1. The relationship of the global seismic activity with variations in the angular velocity of the Earth's rotation for 1720 - 2014 years

    NASA Astrophysics Data System (ADS)

    Sasorova, Elena; Levin, Boris

    2016-04-01

    It is known that the seismic activity (SA) of the Earth is unstable both in time and in space. Periods of increase in seismic activity alternate with periods of its decrease. The objective of this work is to analyze the spatial-temporal the distributions of the density of seismic events and relationship between the global CA and variations in the angular velocity of the Earth's rotation (AVER). A density of the observed seismic events in the 1700-1895 years is several times less than in the period 1895-2014, so we carried out a separate analysis for both periods. To construct the spatial distributions of earthquake sources, we subdivided the Earth's surface into 18 latitudinal belts of 10° in extent. To analyze the temporal distribution, the entire observation period was subdivided into 5-year intervals and total number of events within each 5-year interval was calculated. To prepare the working catalog of strong earthquakes for the period of 1700-1895, we used the catalog of considerable earthquakes on Earth since 2150 B.C. compiled by NEIC from the NOAA database. We extracted events with M>=7.5. The total number of events is equal to 72 (38 in the Northern Hemisphere and 34 in the Southern one). Scatterplot for selected events (for latitude and time) and temporal distribution of events in five-year intervals were built. It is found that earthquakes to the north of latitude 60N and to the south of latitude 60S latitude were not observed. The Earth's SA has clearly expressed bimodal latitudinal distribution: two peaks in middle latitudes of the Northern Hemisphere (40°N-50°N) and the Southern Hemisphere (10°S-30°S), and the local minimum near the Equator. The same analysis was carried out for period 1890-2014 years (period of instrumental observations) and the similar bimodal distributions were obtained. The working catalog for the AVER for period 1720-2014 years was compiled on the basis of the world-known database IERS and data presented in the work [Mc

  2. Actuator assembly including a single axis of rotation locking member

    DOEpatents

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  3. A novel neural network based image reconstruction model with scale and rotation invariance for target identification and classification for Active millimetre wave imaging

    NASA Astrophysics Data System (ADS)

    Agarwal, Smriti; Bisht, Amit Singh; Singh, Dharmendra; Pathak, Nagendra Prasad

    2014-12-01

    Millimetre wave imaging (MMW) is gaining tremendous interest among researchers, which has potential applications for security check, standoff personal screening, automotive collision-avoidance, and lot more. Current state-of-art imaging techniques viz. microwave and X-ray imaging suffers from lower resolution and harmful ionizing radiation, respectively. In contrast, MMW imaging operates at lower power and is non-ionizing, hence, medically safe. Despite these favourable attributes, MMW imaging encounters various challenges as; still it is very less explored area and lacks suitable imaging methodology for extracting complete target information. Keeping in view of these challenges, a MMW active imaging radar system at 60 GHz was designed for standoff imaging application. A C-scan (horizontal and vertical scanning) methodology was developed that provides cross-range resolution of 8.59 mm. The paper further details a suitable target identification and classification methodology. For identification of regular shape targets: mean-standard deviation based segmentation technique was formulated and further validated using a different target shape. For classification: probability density function based target material discrimination methodology was proposed and further validated on different dataset. Lastly, a novel artificial neural network based scale and rotation invariant, image reconstruction methodology has been proposed to counter the distortions in the image caused due to noise, rotation or scale variations. The designed neural network once trained with sample images, automatically takes care of these deformations and successfully reconstructs the corrected image for the test targets. Techniques developed in this paper are tested and validated using four different regular shapes viz. rectangle, square, triangle and circle.

  4. External radiation surveillance

    SciTech Connect

    Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site.

  5. Shoot the Stars--Focus on Earth's Rotation.

    ERIC Educational Resources Information Center

    Russo, Richard

    1988-01-01

    Provides background information on the equipment and knowledge necessary to do an astronomy activity on the earth's rotation. Details an activity in which students can measure the rotation of the earth using a camera and the stars. (CW)

  6. Equilibrium, multistability, and chiral asymmetry in rotated mirror plasmas

    SciTech Connect

    Valanju, P.M.; Mahajan, S.M.; Quevedo, H.J.

    2006-06-15

    The Hall term in two-fluid magnetohydrodynamics is shown to be necessary to balance the curl of the ion inertial force in a rotating plasma with spatially nonuniform crossed electric and magnetic fields. Two-fluid solutions are obtained that qualitatively explain the multistable rotational response observed in magneto-Bernoulli experiment, imply chiral symmetry breaking, i.e., handedness, and yield new dynamo-like electromotive terms in the effective circuit equation for externally rotated mirror plasma equilibria.

  7. Frozen translational and rotational motion of human immunodeficiency virus transacting activator of transcription peptide-modified nanocargo on neutral lipid bilayer.

    PubMed

    Wei, Lin; Zhao, Xin; Chen, Bo; Li, Hongchang; Xiao, Lehui; Yeung, Edward S

    2013-05-21

    With time-resolved high-precision single-particle tracking methodologies, we explored the adsorption and thermal motion of transacting activator of transcription (TAT) peptide-modified nanocargo on a model lipid bilayer in the nonelectrostatic domain. We found that the lateral and rotational motion of TAT peptide-modified nanocargo could be effectively suppressed on the surface of neutral lipid membrane, a feature that cannot be explained by existing hypotheses. A semiquantitative association activation energy analysis revealed that multiple weak bonds were required for the initial adsorption process. As a result, the localized multiple TAT peptides on the surface of the nanocargo can provide a pathway for the creation of a net of peptide-lipid complexes (e.g., lipid domain). The dragging forces caused by these complexes effectively confined the thermal motion of the nanocargo on the fluid membrane that cannot be achieved by individual peptides with random spatial and conformational distributions. These interesting findings could provide insightful information for the better understanding of the intracellular internalization mechanism of TAT peptide-modified nanocargo and might shed new light on the development of highly efficient intracellular carriers for site-specific delivery of drugs and genes.

  8. The transportation external coordination working group

    SciTech Connect

    1995-10-01

    In an effort to improve coordinated interactions between the United States Department of Energy (DOE) and external groups interested in transportation activities, DOE established the Transportation External Coordination Working Group (TEC/WG). Membership includes representatives from State, Tribal and local governments, industry, and professional organizations. All DOE programs with significant transportation programs participate.

  9. Two- vs. Three-Dimensional Presentation of Mental Rotation Tasks: Sex Differences and Effects of Training on Performance and Brain Activation

    ERIC Educational Resources Information Center

    Neubauer, Aljoscha C.; Bergner, Sabine; Schatz, Martina

    2010-01-01

    The well-documented sex difference in mental rotation favoring males has been shown to emerge only for 2-dimensional presentations of 3-dimensional objects, but not with actual 3-dimensional objects or with virtual reality presentations of 3-dimensional objects. Training studies using computer games with mental rotation-related content have…

  10. External approach to rhinoplasty.

    PubMed

    Goodman, Wilfred S; Charbonneau, Paul A

    2015-07-01

    The technique of external rhinoplasty is outlined. Having reviewed 74 cases, its advantages and disadvantages are discussed. Reluctance to use this external approach seems to be based on emotional rather than radical grounds, for its seems to be the procedure of choice for many problems.

  11. External Cargo Integration Overview

    NASA Technical Reports Server (NTRS)

    Gueera, Alan

    2005-01-01

    This viewgraph presentation reviews the system integration efforts for external cargo for the International Space Station (ISS). The role and responsibility of the External Carriers Ofice is reviewed. The presentation also reviews the application of the office to the Commercial Cargo Services contract.

  12. Humeral rotational osteotomy for shoulder deformity in obstetric brachial plexus palsy: which direction should I rotate?

    PubMed

    Abdelgawad, Amr A; Pirela-Cruz, Miguel A

    2014-01-01

    Shoulder internal rotation contracture is the most common deformity affecting the shoulder in patients with Obstetric Brachial Plexus Palsy. With progression of the deformity, the glenohumeral joint starts to subluxate and then dislocates. This is accompanied with bony changes of both the humerus and the glenoid. Two opposite direction humeral osteotomies have been proposed for this condition (internal rotation osteotomy (IRO) and external rotation osteotomy (ERO)). This fact of different direction osteotomies has not adequately been explained in the literature. Most orthopedic surgeons may not be able to fully differentiate between these two osteotomies regarding the indications, outcomes and effects on the joint. This review explains these differences in details.

  13. Rotation of cometary meteoroids

    NASA Astrophysics Data System (ADS)

    Čapek, D.

    2014-08-01

    Aims: The rotation of meteoroids caused by gas drag during the ejection from a cometary nucleus has not been studied yet. The aim of this study is to estimate the rotational characteristics of meteoroids after their release from a comet during normal activity. Methods: The basic dependence of spin rate on ejection velocity and meteoroid size is determined analytically. A sophisticated numerical model is then applied to meteoroids ejected from the 2P/Encke comet. The meteoroid shapes are approximated by polyhedrons, which have been determined by a 3D laser scanning method of 36 terrestrial rock samples. These samples come from three distinct sets with different origins and characteristics, such as surface roughness or angularity. Two types of gas-meteoroid interactions and three gas ejection models are assumed. The rotational characteristics of ejected meteoroid population are obtained by numerical integration of equations of motion with random initial conditions and random shape selection. Results: It is proved that the results do not depend on a specific set of shape models and that they are applicable to the (unknown) shapes of real meteoroids. A simple relationship between the median of meteoroid spin frequencies bar{f} (Hz), ejection velocities vej (m s-1), and sizes D (m) is determined. For diffuse reflection of gas molecules from meteoroid's surface it reads as bar{f≃ 2× 10-3 v_ej D-0.88}, and for specular reflection of gas molecules from meteoroid's surface it is bar{f≃ 5× 10-3 v_ej D-0.88}. The distribution of spin frequencies is roughly normal on log scale, and it is relatively wide: a 2σ-interval can be described as (0.1, 10)× bar{f}. Most of the meteoroids are non-principal axis rotators. The median angle between angular momentum vector and spin vector is 12°. About 60% of meteoroids rotate in long-axis mode. The distribution of angular momentum vectors is not random. They are concentrated in the perpendicular direction with respect to the gas

  14. NUMERICAL SIMULATIONS OF Z-PINCH EXPERIMENTS TO CREATE SUPERSONIC DIFFERENTIALLY ROTATING PLASMA FLOWS

    SciTech Connect

    Bocchi, M.; Ummels, B.; Chittenden, J. P.; Lebedev, S. V.; Frank, A.; Blackman, E. G.

    2013-04-10

    The physics of accretion disks is of fundamental importance for understanding of a wide variety of astrophysical sources that includes protostars, X-ray binaries, and active galactic nuclei. The interplay between hydrodynamic flows and magnetic fields and the potential for turbulence-producing instabilities is a topic of active research that would benefit from the support of dedicated experimental studies. Such efforts are in their infancy, but in an effort to push the enterprise forward we propose an experimental configuration which employs a modified cylindrical wire array Z-pinch to produce a rotating plasma flow relevant to accretion disks. We present three-dimensional resistive magnetohydrodynamic simulations which show how this approach can be implemented. In the simulations, a rotating plasma cylinder or ring is formed, with typical rotation velocity {approx}30 km s{sup -1}, Mach number {approx}4, and Reynolds number in excess of 10{sup 7}. The plasma is also differentially rotating. Implementation of different external magnetic field configurations is discussed. It is found that a modest uniform vertical field of 1 T can affect the dynamics of the system and could be used to study magnetic field entrainment and amplification through differential rotation. A dipolar field potentially relevant to the study of accretion columns is also considered.

  15. Effect of rotator cuff exercise on humeral rotation torque in healthy individuals.

    PubMed

    Moncrief, Scott A; Lau, Jeffery D; Gale, Judith R; Scott, Samuel A

    2002-05-01

    Conservative management of rotator cuff pathology often involves certain therapeutic exercises. Although a major goal of these exercises is to increase strength of the rotator cuff, little empirical evidence supports this assertion. In this study, 34 nonpathologic young adults were pretested using a LIDO Multijoint II isokinetic device for average and peak torque generated during internal and external rotation. Subjects were arbitrarily assigned to a right-arm- or left-arm-trained group, exercised for 4 weeks, and then posttested for changes in humeral rotation torque. Moderate but significant increases in torque (8-10%) as well as in total work done were observed in both groups, only in the trained arm. Subjects who trained the nondominant (left) arm experienced gains similar to those who trained the right arm. Gains were significant in the case of both internal and external rotation (also average as well as peak torque), with men and women experiencing the same relative increases. These data, in addition to supporting the use of selected exercises to increase humeral rotation torque in a healthy population, offer a potential model for the rehabilitation of patients with rotator cuff injury. PMID:11991780

  16. Rotational Preference in Gymnastics

    PubMed Central

    Heinen, Thomas; Jeraj, Damian; Vinken, Pia M.; Velentzas, Konstantinos

    2012-01-01

    In gymnastics, most skills incorporate rotations about one or more body axes. At present, the question remains open if factors such as lateral preference and/or vestibulo-spinal asymmetry are related to gymnast’s rotational preference. Therefore, we sought to explore relationships in gymnast’s rotation direction between different gymnastic skills. Furthermore, we sought to explore relationships between rotational preference, lateral preference, and vestibulo-spinal asymmetry. In the experiment n = 30 non-experts, n = 30 near-experts and n = 30 experts completed a rotational preference questionnaire, a lateral preference inventory, and the Unterberger-Fukuda Stepping Test. The results revealed, that near-experts and experts more often rotate rightward in the straight jump with a full turn when rotating leftward in the round-off and vice versa. The same relationship was found for experts when relating the rotation preference in the handstand with a full turn to the rotation preference in the straight jump with a full turn. Lateral preference was positively related to rotational preference in non-expert gymnasts, and vestibulo-spinal asymmetry was positively related to rotational preference in experts. We suggest, that gymnasts should explore their individual rotational preference by systematically practicing different skills with a different rotation direction, bearing in mind that a clearly developed structure in rotational preference between different skills may be appropriate to develop more complex skills in gymnastics. PMID:23486362

  17. Rotational preference in gymnastics.

    PubMed

    Heinen, Thomas; Jeraj, Damian; Vinken, Pia M; Velentzas, Konstantinos

    2012-06-01

    In gymnastics, most skills incorporate rotations about one or more body axes. At present, the question remains open if factors such as lateral preference and/or vestibulo-spinal asymmetry are related to gymnast's rotational preference. Therefore, we sought to explore relationships in gymnast's rotation direction between different gymnastic skills. Furthermore, we sought to explore relationships between rotational preference, lateral preference, and vestibulo-spinal asymmetry. In the experiment n = 30 non-experts, n = 30 near-experts and n = 30 experts completed a rotational preference questionnaire, a lateral preference inventory, and the Unterberger-Fukuda Stepping Test. The results revealed, that near-experts and experts more often rotate rightward in the straight jump with a full turn when rotating leftward in the round-off and vice versa. The same relationship was found for experts when relating the rotation preference in the handstand with a full turn to the rotation preference in the straight jump with a full turn. Lateral preference was positively related to rotational preference in non-expert gymnasts, and vestibulo-spinal asymmetry was positively related to rotational preference in experts. We suggest, that gymnasts should explore their individual rotational preference by systematically practicing different skills with a different rotation direction, bearing in mind that a clearly developed structure in rotational preference between different skills may be appropriate to develop more complex skills in gymnastics. PMID:23486362

  18. Analysis of scapular kinematics during active and passive arm elevation

    PubMed Central

    Kai, Yoshihiro; Gotoh, Masafumi; Takei, Kazuto; Madokoro, Kazuya; Imura, Takeshi; Murata, Shin; Morihara, Toru; Shiba, Naoto

    2016-01-01

    [Purpose] Early postoperative passive motion exercise after arthroscopic rotator cuff repair remains controversial. To better understand this issue, this study was aimed at evaluating scapular kinematics and muscle activities during passive arm elevation in healthy subjects. [Subjects and Methods] The dominant shoulders of 27 healthy subjects were examined. Electromagnetic sensors attached to the scapula, thorax, and humerus were used to determine three-dimensional scapular kinematics during active arm elevation with or without external loads and passive arm elevation. Simultaneously, the activities of seven shoulder muscles were recorded with surface and intramuscular fine-wire electrodes. [Results] Compared with active arm elevation, passive elevation between 30° and 100° significantly decreased the scapular upward rotation and increased the glenohumeral elevation angle. However, no significant differences in scapular posterior tilt and external rotation were observed between active and passive arm elevation, and scapular plane kinematics were not affected by muscle activity. [Conclusion] Unlike active motion with or without an external load, passive arm elevation significantly decreased the scapular upward rotation and significantly increased the mid-range glenohumeral elevation. These data, which suggest that passive arm elevation should be avoided during the early postoperative period, may expand the understanding of rehabilitation after arthroscopic rotator cuff repair. PMID:27390438

  19. Reverse shoulder arthroplasty using an implant with a lateral center of rotation: outcomes, complications, and the influence of experience.

    PubMed

    Hasan, Samer S; Gordon, Matthew P; Ramsey, Jason A; Levy, Martin S

    2014-09-01

    Reverse shoulder arthroplasty (RSA) has revolutionized treatment of arthritis and rotator cuff insufficiency and is performed using implants with either a medial or a lateral center of rotation. We conducted a study of the outcomes and the effect of surgeon learning after the first 60 consecutive lateral-center-of-rotation RSAs implanted by a single surgeon unaffiliated with the design team for this particular reverse shoulder prosthesis. At minimum 2-year followup, mean improvements in active forward elevation, abduction, and external rotation were 69°, 55°, and 23°, respectively; mean active internal rotation improved significantly as well (P < .001 for all). Mean Simple Shoulder Test (SST) scores improved from 1.8 (range, 0-6) to 6.9 (range, 0-12) (P < .0001), and mean final American Shoulder and Elbow Surgeons score was 72 (range, 27-100). Final radiographs showed scapular notching in 5 shoulders (11%). Gains in SST scores, active forward elevation, and active abduction were lower for the first 15 cases than for the next 45 cases, and 5 of the 8 reoperations were performed after the first 15 cases. Overall improvements in active motion and self-assessed shoulder function in this series are comparable to those previously reported by the design team. Experience with RSA appears to influence efficacy, but the learning curve may not be as steep as previously reported.

  20. Nearshore sandbar rotation at single-barred embayed beaches

    NASA Astrophysics Data System (ADS)

    Blossier, B.; Bryan, K. R.; Daly, C. J.; Winter, C.

    2016-04-01

    The location of a shore-parallel nearshore sandbar derived from 7 years of video imagery data at the single-barred embayed Tairua Beach (NZ) is investigated to assess the contribution of barline rotation to the overall morphodynamics of sandbars in embayed environments and to characterize the process of rotation in relation to external conditions. Rotation induces cross-shore barline variations at the embayment extremities on the order of magnitude of those induced by alongshore uniform cross-shore migration of the bar. Two semiempirical models have been developed to relate the barline cross-shore migration and rotation to external wave forcing conditions. The rotation model is directly derived from the cross-shore migration model. Therefore, its formulation advocates for a primary role of cross-shore processes in the rotation of sandbars at embayed beaches. The orientation evolves toward an equilibrium angle directly related to the alongshore wave energy gradient due to two different mechanisms. Either the bar extremities migrate in opposite directions with no overall cross-shore bar migration (pivotal rotation) or the rotation relates to an overall migration of the barline which is not uniform along the beach (migration-driven rotation). Migration and rotation characteristic response times are similar, ranging from 10 to 30 days for mild and energetic wave conditions and above 200 days during very calm conditions or when the bar is located far offshore.

  1. Influence of pelvis rotation styles on baseball pitching mechanics.

    PubMed

    Wight, Jeff; Richards, James; Hall, Susan

    2004-01-01

    Efficient, sequential timing is essential for upper level pitching. Interestingly, pitchers vary considerably in timing related elements of pitching style including pelvis rotation, arm cocking, stride leg behaviour, and pitch delivery time. The purpose of this study was to determine whether relationships exist among these elements by examining the overall style of pitchers exhibiting different pelvis rotation patterns. Pitching styles were defined by pelvis orientation at the instant of stride foot contact. Pitchers demonstrating a pelvis orientation greater than 30 degrees were designated as 'early rotators', while pitchers demonstrating a pelvis orientation less than 30 degrees were designated as 'late rotators'. Kinematic and temporal differences were associated with the two styles. During the arm cocking phase, early rotators showed significantly greater shoulder external rotation at the instant of stride foot contact, earlier occurrence of maximum pelvis rotation angular velocity, and shorter time taken to complete the phase. However, by the instant of maximum shoulder external rotation, early and late rotators appeared remarkably similar as no significant difference occurred in pelvis and arm orientations. Therefore, it appears that early and late rotators used different methods to achieve similar results, including throwing velocity. Significant differences in throwing arm kinetics were also found for 10 of the 11 measures in the study. As the pelvis assumed a more open position at stride foot contact, maximum kinetic values were found to both decrease in magnitude and occur at an earlier time within the pitch.

  2. Rotator cuff injuries in adolescent athletes.

    PubMed

    Weiss, Jennifer M; Arkader, Alexandre; Wells, Lawrence M; Ganley, Theodore J

    2013-03-01

    The cause of rotator cuff injuries in the young athlete has been described as an overuse injury related to internal impingement. Abduction coupled with external rotation is believed to impinge on the rotator cuff, specifically the supraspinatus, and lead to undersurface tears that can progress to full-thickness tears. This impingement is believed to be worsened with increased range of motion and instability in overhead athletes. A retrospective review of seven patients diagnosed with rotator cuff injuries was performed to better understand this shoulder injury pattern. The type of sport played, a history of trauma, diagnosis, treatment method, and outcome were noted. Six patients were male and one was a female. Baseball was the primary sport for four patients, basketball for one, gymnastics for one, and wrestling for one. The following injury patterns were observed: two patients tore their subscapularis tendon, two sustained avulsion fractures of their lesser tuberosity, one tore his rotator interval, one tore his supraspinatus, and one avulsed his greater tuberosity. Only four patients recalled a specific traumatic event. Three patients were treated with arthroscopic rotator cuff repair, three with miniopen repair, and one was treated with rehabilitation. Six of the seven patients returned to their preinjury level of sport after treatment. Rotator cuff tears are rare in the adolescent age group. The injury patterns suggest that acute trauma likely accounts for many rotator cuff tears and their equivalents in the young patient. Adolescents with rotator cuff tears reliably return to sports after treatment. The possibility of rotator cuff tears in skeletally immature athletes should be considered. The prognosis is very good once this injury is identified and treated. PMID:22668571

  3. Rotator cuff injuries in adolescent athletes.

    PubMed

    Weiss, Jennifer M; Arkader, Alexandre; Wells, Lawrence M; Ganley, Theodore J

    2013-03-01

    The cause of rotator cuff injuries in the young athlete has been described as an overuse injury related to internal impingement. Abduction coupled with external rotation is believed to impinge on the rotator cuff, specifically the supraspinatus, and lead to undersurface tears that can progress to full-thickness tears. This impingement is believed to be worsened with increased range of motion and instability in overhead athletes. A retrospective review of seven patients diagnosed with rotator cuff injuries was performed to better understand this shoulder injury pattern. The type of sport played, a history of trauma, diagnosis, treatment method, and outcome were noted. Six patients were male and one was a female. Baseball was the primary sport for four patients, basketball for one, gymnastics for one, and wrestling for one. The following injury patterns were observed: two patients tore their subscapularis tendon, two sustained avulsion fractures of their lesser tuberosity, one tore his rotator interval, one tore his supraspinatus, and one avulsed his greater tuberosity. Only four patients recalled a specific traumatic event. Three patients were treated with arthroscopic rotator cuff repair, three with miniopen repair, and one was treated with rehabilitation. Six of the seven patients returned to their preinjury level of sport after treatment. Rotator cuff tears are rare in the adolescent age group. The injury patterns suggest that acute trauma likely accounts for many rotator cuff tears and their equivalents in the young patient. Adolescents with rotator cuff tears reliably return to sports after treatment. The possibility of rotator cuff tears in skeletally immature athletes should be considered. The prognosis is very good once this injury is identified and treated.

  4. Hip Rotational Velocities During the Full Golf Swing

    PubMed Central

    Gulgin, Heather; Armstrong, Charles; Gribble, Phillip

    2009-01-01

    Since labral pathology in professional golfers has been reported, and such pathology has been associated with internal/external hip rotation, quantifying the rotational velocity of the hips during the golf swing may be helpful in understanding the mechanism involved in labral injury. Thus, the purpose of this study was to determine the peak internal/external rotational velocities of the thigh relative to the pelvis during the golf swing. Fifteen female, collegiate golfers participated in the study. Data were acquired through high-speed three dimensional (3-D) videography using a multi-segment bilateral marker set to define the segments, while the subjects completed multiple repetitions of a drive. The results indicated that the lead hip peak internal rotational velocity was significantly greater than that of the trail hip external rotational velocity (p = 0.003). It appears that the lead hip of a golfer experiences much higher rotational velocities during the downswing than that of the trail hip. In other structures, such as the shoulder, an increased risk of soft tissue injury has been associated with high levels of rotational velocity. This may indicate that, in golfers, the lead hip may be more susceptible to injury such as labral tears than that of the trailing hip. Key points Lead hip of golfer experiences significantly higher rotational velocities than the trail hip. Golfers may be more susceptible to injuries on the lead hip. Clubhead velocities were consistent with elite female golfers. PMID:24149541

  5. Improving spatial updating accuracy in absence of external feedback.

    PubMed

    Mackrous, I; Simoneau, M

    2015-08-01

    Updating the position of an earth-fixed target during whole-body rotation seems to rely on cognitive processes such as the utilization of external feedback. According to perceptual learning models, improvement in performance can also occur without external feedback. The aim of this study was to assess spatial updating improvement in the absence and in the presence of external feedback. While being rotated counterclockwise (CCW), participants had to predict when their body midline had crossed the position of a memorized target. Four experimental conditions were tested: (1) Pre-test: the target was presented 30° in the CCW direction from participant's midline. (2) Practice: the target was located 45° in the CCW direction from participant's midline. One group received external feedback about their spatial accuracy (Mackrous and Simoneau, 2014) while the other group did not. (3) Transfer T(30)CCW: the target was presented 30° in the CCW direction to evaluate whether improvement in performance, during practice, generalized to other target eccentricity. (4) Transfer T(30)CW: the target was presented 30° in the clockwise (CW) direction and participants were rotated CW. This transfer condition evaluated whether improvement in performance generalized to the untrained rotation direction. With practice, performance improved in the absence of external feedback (p=0.004). Nonetheless, larger improvement occurred when external feedback was provided (ps=0.002). During T(30)CCW, performance remained better for the feedback than the no-feedback group (p=0.005). However, no group difference was observed for the untrained direction (p=0.22). We demonstrated that spatial updating improved without external feedback but less than when external feedback was given. These observations are explained by a mixture of calibration processes and supervised vestibular learning.

  6. Future of External Reporting

    ERIC Educational Resources Information Center

    Powers, Kristina

    2015-01-01

    This chapter builds on prior chapters and focuses on higher education trends on the horizon and the resulting impact on external reporting for institutional researchers. Three practical recommendations and examples for institutional researchers are also presented.

  7. Migration with fiscal externalities.

    PubMed

    Hercowitz, Z; Pines, D

    1991-11-01

    "This paper analyses the distribution of a country's population among regions when migration involves fiscal externalities. The main question addressed is whether a decentralized decision making [by] regional governments can produce an optimal population distribution...or a centralized intervention is indispensable, as argued before in the literature.... It turns out that, while with costless mobility the fiscal externality is fully internalized by voluntary interregional transfers, with costly mobility, centrally coordinated transfers still remain indispensable for achieving the socially optimal allocation."

  8. Power Harvesting from Rotation?

    ERIC Educational Resources Information Center

    Chicone, Carmen; Feng, Z. C.

    2008-01-01

    We show the impossibility of harvesting power from rotational motions by devices attached to the rotating object. The presentation is suitable for students who have studied Lagrangian mechanics. (Contains 2 figures.)

  9. Rotator cuff problems

    MedlinePlus

    ... rotator cuff is a group of muscles and tendons that attach to the bones of the shoulder ... Rotator cuff tendinitis refers to irritation of these tendons and inflammation of the bursa (a normally smooth ...

  10. Externally modulated theranostic nanoparticles

    PubMed Central

    Urban, Cordula; Urban, Alexander S.; Charron, Heather; Joshi, Amit

    2013-01-01

    Externally modulated nanoparticles comprise a rapidly advancing class of cancer nanotherapeutics, which combine the favorable tumor accumulation of nanoparticles, with external spatio-temporal control on therapy delivery via optical, magnetic, or ultrasound modalities. The local control on therapy enables higher tumor treatment efficacy, while simultaneously reducing off-target effects. The nanoparticle interactions with external fields have an additional advantage of frequently generating an imaging signal, and thus such agents provide theranostic (both diagnostic and therapeutic) capabilities. In this review, we classify the emerging externally modulated theranostic nanoparticles according to the mode of external control and describe the physiochemical mechanisms underlying the external control of therapy, and illustrate the major embodiments of nanoparticles in each class with proven biological efficacy: (I) electromagnetic radiation in visible and near-infrared range is being exploited for gold based and carbon nanostructures with tunable surface plasmon resonance (SPR) for imaging and photothermal therapy (PTT) of cancer, photochemistry based manipulations are employed for light sensitive liposomes and porphyrin based nanoparticles; (II) Magnetic field based manipulations are being developed for iron-oxide based nanostructures for magnetic resonance imaging (MRI) and magnetothermal therapy; (III) ultrasound based methods are primarily being employed to increase delivery of conventional drugs and nanotherapeutics to tumor sites. PMID:24834381

  11. Externally modulated theranostic nanoparticles.

    PubMed

    Urban, Cordula; Urban, Alexander S; Charron, Heather; Joshi, Amit

    2013-08-01

    Externally modulated nanoparticles comprise a rapidly advancing class of cancer nanotherapeutics, which combine the favorable tumor accumulation of nanoparticles, with external spatio-temporal control on therapy delivery via optical, magnetic, or ultrasound modalities. The local control on therapy enables higher tumor treatment efficacy, while simultaneously reducing off-target effects. The nanoparticle interactions with external fields have an additional advantage of frequently generating an imaging signal, and thus such agents provide theranostic (both diagnostic and therapeutic) capabilities. In this review, we classify the emerging externally modulated theranostic nanoparticles according to the mode of external control and describe the physiochemical mechanisms underlying the external control of therapy, and illustrate the major embodiments of nanoparticles in each class with proven biological efficacy: (I) electromagnetic radiation in visible and near-infrared range is being exploited for gold based and carbon nanostructures with tunable surface plasmon resonance (SPR) for imaging and photothermal therapy (PTT) of cancer, photochemistry based manipulations are employed for light sensitive liposomes and porphyrin based nanoparticles; (II) Magnetic field based manipulations are being developed for iron-oxide based nanostructures for magnetic resonance imaging (MRI) and magnetothermal therapy; (III) ultrasound based methods are primarily being employed to increase delivery of conventional drugs and nanotherapeutics to tumor sites.

  12. Rotations with Rodrigues' Vector

    ERIC Educational Resources Information Center

    Pina, E.

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears…

  13. Dynamics of molecular superrotors in an external magnetic field

    NASA Astrophysics Data System (ADS)

    Korobenko, Aleksey; Milner, Valery

    2015-08-01

    We excite diatomic oxygen and nitrogen to high rotational states with an optical centrifuge and study their dynamics in an external magnetic field. Ion imaging is employed to directly visualize, and follow in time, the rotation plane of the molecular superrotors. The two different mechanisms of interaction between the magnetic field and the molecular angular momentum in paramagnetic oxygen and non-magnetic nitrogen lead to qualitatively different behaviour. In nitrogen, we observe the precession of the molecular angular momentum around the field vector. In oxygen, strong spin-rotation coupling results in faster and richer dynamics, encompassing the splitting of the rotation plane into three separate components. As the centrifuged molecules evolve with no significant dispersion of the molecular wave function, the observed magnetic interaction presents an efficient mechanism for controlling the plane of molecular rotation.

  14. Rotator Cuff Tendinitis and Tear (Beyond the Basics)

    MedlinePlus

    ... is usually treated with ice, antiinflammatory drugs, and physical therapy. (See 'Rotator cuff injury treatment' below.) Rotator cuff ... small- to medium-size tears usually improve with physical therapy exercises, stopping painful activities, and, in some cases, ...

  15. Rotating electric machine with fluid supported parts

    DOEpatents

    Smith, Jr., Joseph L.; Kirtley, Jr., James L.

    1981-01-01

    A rotating electric machine in which the armature winding thereof and other parts are supported by a liquid to withstand the mechanical stresses applied during transient overloads and the like. In particular, a narrow gap is provided between the armature winding and the stator which supports it and this gap is filled with an externally pressurized viscous liquid. The liquid is externally pressurized sufficiently to balance the static loads on the armature winding. Transient mechanical loads which deform the armature winding alter the gap dimensions and thereby additionally pressurize the viscous liquid to oppose the armature winding deformation and more nearly uniformly to distribute the resulting mechanical stresses.

  16. Dynamic Interplay of Coherent Rotations and Domain Wall Motion in Faraday Rotators based on Ferromagnetic Crystals

    NASA Astrophysics Data System (ADS)

    Garzarella, Anthony; Wu, Dong; Shinn, Mannix

    Under small, externally-applied magnetic fields, the Faraday rotation in magneto-optic material containing ferromagnetic domains is driven primarily by two principal mechanisms: domain wall motion and coherent domain rotations. Domain wall motion yields a larger Faraday responsivity but is limited by magnetically induced optical incoherence and by damping effects. Coherent domain rotation yields smaller Faraday rotations, but exhibits a flatter and broader frequency response. The two mechanisms occur along orthogonal principal axes and may be probed independently. However, when probed along an oblique angle to the principal axes, the relationship between the Faraday rotation and the external field changes from linear to tensorial. Although this may lead to more complicated phenomena (e.g. a sensitivity axis that depends on RF frequency), the interplay of domain rotation and domain wall motion can be exploited to improve responsivity or bandwidth. The detailed experimental data can be understood in terms of a quantitative model for the magnitude and direction of the responsivity vector. Applications to magnetic field sensors based on arrayed bismuth doped iron garnet films will be emphasized in this presentation.

  17. SEAL FOR ROTATING SHAFT

    DOEpatents

    Coffman, R.T.

    1957-12-10

    A seal is described for a rotatable shaft that must highly effective when the shaft is not rotating but may be less effective while the shaft is rotating. Weights distributed about a sealing disk secured to the shaft press the sealing disk against a tubular section into which the shiilt extends, and whem the shaft rotates, the centrifugal forces on the weights relieve the pressurc of the sealing disk against the tubular section. This action has the very desirible result of minimizing the wear of the rotating disk due to contact with the tubular section, while affording maximum sealing action when it is needed.

  18. Fluorescence spectra and biological activity of aerosolized bacillus spores and MS2 bacteriophage exposed to ozone at different relative humidities in a rotating drum

    NASA Astrophysics Data System (ADS)

    Ratnesar-Shumate, Shanna; Pan, Yong-Le; Hill, Steven C.; Kinahan, Sean; Corson, Elizabeth; Eshbaugh, Jonathan; Santarpia, Joshua L.

    2015-03-01

    Biological aerosols (bioaerosols) released into the environment may undergo physical and chemical transformations when exposed to atmospheric constituents such as solar irradiation, reactive oxygenated species, ozone, free radicals, water vapor and pollutants. Aging experiments were performed in a rotating drum chamber subjecting bioaerosols, Bacillus thuringiensis Al Hakam (BtAH) spores and MS2 bacteriophages to ozone at 0 and 150 ppb, and relative humidities (RH) at 10%, 50%, and 80+%. Fluorescence spectra and intensities of the aerosols as a function of time in the reaction chamber were measured with a single particle fluorescence spectrometer (SPFS) and an Ultra-Violet Aerodynamic Particle Sizer® Spectrometer (UV-APS). Losses in biological activity were measured by culture and quantitative polymerase chain reaction (q-PCR) assay. For both types of aerosols the largest change in fluorescence emission was between 280 and 400 nm when excited at 263 nm followed by fluorescence emission between 380 and 700 nm when excited at 351 nm. The fluorescence for both BtAH and MS2 were observed to decrease significantly at high ozone concentration and high RH when excited at 263 nm excitation. The decreases in 263 nm excited fluorescence are indicative of hydrolysis and oxidation of tryptophan in the aerosols. Fluorescence measured with the UV-APS (355-nm excitation) increased with time for both BtAH and MS2 aerosols. A two log loss of MS2 bacteriophage infectivity was observed in the presence of ozone at ~50% and 80% RH when measured by culture and normalized for physical losses by q-PCR. Viability of BtAH spores after exposure could not be measured due to the loss of genomic material during experiments, suggesting degradation of extracelluar DNA attributable to oxidation. The results of these studies indicate that the physical and biological properties of bioaerosols change significantly after exposure to ozone and water vapor.

  19. Fluorescence spectra and biological activity of aerosolized bacillus spores and MS2 bacteriophage exposed to ozone at different relative humidities in a rotating drum

    DOE PAGES

    Ratnesar-Shumate, Shanna; Pan, Yong-Le; Hill, Steven C.; Kinahan, Sean; Corson, Elizabeth; Eshbaugh, Jonathan; Santarpia, Joshua L.

    2015-10-14

    Biological aerosols (bioaerosols) released into the environment may undergo physical and chemical transformations when exposed to atmospheric constituents such as solar irradiation, reactive oxygenated species, ozone, free radicals, water vapor and pollutants. Aging experiments were performed in a rotating drum chamber subjecting bioaerosols, Bacillus thuringiensis Al Hakam (BtAH) spores and MS2 bacteriophages to ozone at 0 and 150 ppb, and relative humidities (RH) at 10%, 50%, and 80+%. Fluorescence spectra and intensities of the aerosols as a function of time in the reaction chamber were measured with a single particle fluorescence spectrometer (SPFS) and an Ultra-Violet Aerodynamic Particle Sizer® Spectrometermore » (UV-APS). Losses in biological activity were measured by culture and quantitative polymerase chain reaction (q-PCR) assay. For both types of aerosols the largest change in fluorescence emission was between 280 and 400 nm when excited at 263 nm followed by fluorescence emission between 380 and 700 nm when excited at 351 nm. The fluorescence for both BtAH and MS2 were observed to decrease significantly at high ozone concentration and high RH when excited at 263 nm excitation. The decreases in 263 nm excited fluorescence are indicative of hydrolysis and oxidation of tryptophan in the aerosols. Fluorescence measured with the UV-APS (355-nm excitation) increased with time for both BtAH and MS2 aerosols. A two log loss of MS2 bacteriophage infectivity was observed in the presence of ozone at ~50% and 80% RH when measured by culture and normalized for physical losses by q-PCR. Viability of BtAH spores after exposure could not be measured due to the loss of genomic material during experiments, suggesting degradation of extracelluar DNA attributable to oxidation. The results of these studies indicate that the physical and biological properties of bioaerosols change significantly after exposure to ozone and water vapor.« less

  20. Fluorescence spectra and biological activity of aerosolized bacillus spores and MS2 bacteriophage exposed to ozone at different relative humidities in a rotating drum

    SciTech Connect

    Ratnesar-Shumate, Shanna; Pan, Yong-Le; Hill, Steven C.; Kinahan, Sean; Corson, Elizabeth; Eshbaugh, Jonathan; Santarpia, Joshua L.

    2015-10-14

    Biological aerosols (bioaerosols) released into the environment may undergo physical and chemical transformations when exposed to atmospheric constituents such as solar irradiation, reactive oxygenated species, ozone, free radicals, water vapor and pollutants. Aging experiments were performed in a rotating drum chamber subjecting bioaerosols, Bacillus thuringiensis Al Hakam (BtAH) spores and MS2 bacteriophages to ozone at 0 and 150 ppb, and relative humidities (RH) at 10%, 50%, and 80+%. Fluorescence spectra and intensities of the aerosols as a function of time in the reaction chamber were measured with a single particle fluorescence spectrometer (SPFS) and an Ultra-Violet Aerodynamic Particle Sizer® Spectrometer (UV-APS). Losses in biological activity were measured by culture and quantitative polymerase chain reaction (q-PCR) assay. For both types of aerosols the largest change in fluorescence emission was between 280 and 400 nm when excited at 263 nm followed by fluorescence emission between 380 and 700 nm when excited at 351 nm. The fluorescence for both BtAH and MS2 were observed to decrease significantly at high ozone concentration and high RH when excited at 263 nm excitation. The decreases in 263 nm excited fluorescence are indicative of hydrolysis and oxidation of tryptophan in the aerosols. Fluorescence measured with the UV-APS (355-nm excitation) increased with time for both BtAH and MS2 aerosols. A two log loss of MS2 bacteriophage infectivity was observed in the presence of ozone at ~50% and 80% RH when measured by culture and normalized for physical losses by q-PCR. Viability of BtAH spores after exposure could not be measured due to the loss of genomic material during experiments, suggesting degradation of extracelluar DNA attributable to oxidation. The results of these studies indicate that the physical and biological properties of bioaerosols change significantly after exposure to ozone and water vapor.

  1. Rotation of tokamak halo currents

    SciTech Connect

    Boozer, Allen H.

    2012-05-15

    During tokamak disruptions, halo currents, which can be tenths of the total plasma current, can flow at the plasma edge along the magnetic field lines that intercept the chamber walls. Non-axisymmetric halo currents are required to maintain force balance as the plasma kinks when the edge safety factor drops to about two in a vertical displacement event. The plasma quickly assumes a definite toroidal velocity v{sub a}(r) with respect to that of the magnetic kink, v{sub k}, where v{sub a}(r) is set by the radial electric field required for ambipolarity. The plasma velocity, v{sub pl}=v{sub a}+v{sub k}, near the edge is influenced by the interaction with neutrals and with the potential in the halo required for quasi-neutrality on open magnetic field lines, and the plasma velocity in the core is influenced by external error fields. When plasma effects dominate magnetic locking, the magnetic kink should rotate at a diamagnetic speed of either the edge or the core. If the magnetic field lines of the halo plasma intercept the wall at locations of very different electrical conductivity, the toroidal rotation of the halo currents can intermittently stall at wall locations of high conductivity. Such stalling is seen in experiments. The toroidal phase difference between the stalled halo currents and the kink, which is expected to rotate smoothly, must satisfy {delta}{phi}<{+-}{pi}/2. A concern cited by ITER engineers is that the time varying force of the rotating halo could substantially increase the disruption loads on in-vessel components.

  2. Predictors of human rotation.

    PubMed

    Stochl, Jan; Croudace, Tim

    2013-01-01

    Why some humans prefer to rotate clockwise rather than anticlockwise is not well understood. This study aims to identify the predictors of the preferred rotation direction in humans. The variables hypothesised to influence rotation preference include handedness, footedness, sex, brain hemisphere lateralisation, and the Coriolis effect (which results from geospatial location on the Earth). An online questionnaire allowed us to analyse data from 1526 respondents in 97 countries. Factor analysis showed that the direction of rotation should be studied separately for local and global movements. Handedness, footedness, and the item hypothesised to measure brain hemisphere lateralisation are predictors of rotation direction for both global and local movements. Sex is a predictor of the direction of global rotation movements but not local ones, and both sexes tend to rotate clockwise. Geospatial location does not predict the preferred direction of rotation. Our study confirms previous findings concerning the influence of handedness, footedness, and sex on human rotation; our study also provides new insight into the underlying structure of human rotation movements and excludes the Coriolis effect as a predictor of rotation.

  3. Effects of the axis of rotation and primordially solicited limb of high level athletes in a mental rotation task.

    PubMed

    Habacha, Hamdi; Lejeune-Poutrain, Laure; Margas, Nicolas; Molinaro, Corinne

    2014-10-01

    A recent set of studies has investigated the selective effects of particular physical activities that require full-body rotations, such as gymnastics and wrestling (Moreau, Clerc, Mansy-Dannay, & Guerrien, 2012; Steggemann, Engbert, & Weigelt, 2011), and demonstrated that practicing these activities imparts a clear advantage in in-plane body rotation performance. Other athletes, such as handball and soccer players, whose activities do require body rotations may have more experience with in-depth rotations. The present study examined the effect of two components that are differently solicited in sport practices on the mental rotation ability: the rotation axis (in-plane, in-depth) and the predominantly used limb (arms, legs). Handball players, soccer players, and gymnasts were asked to rotate handball and soccer strike images mentally, which were presented in different in-plane and in-depth orientations. The results revealed that handball and soccer players performed the in-depth rotations faster than in-plane rotations; however, the two rotation axes did not differ in gymnasts. In addition, soccer players performed the mental rotations of handball strike images slower. Our findings suggest that the development of mental rotation tasks that involve the major components of a physical activity allows and is necessary for specifying the links between this activity and the mental rotation performance.

  4. Effects of the axis of rotation and primordially solicited limb of high level athletes in a mental rotation task.

    PubMed

    Habacha, Hamdi; Lejeune-Poutrain, Laure; Margas, Nicolas; Molinaro, Corinne

    2014-10-01

    A recent set of studies has investigated the selective effects of particular physical activities that require full-body rotations, such as gymnastics and wrestling (Moreau, Clerc, Mansy-Dannay, & Guerrien, 2012; Steggemann, Engbert, & Weigelt, 2011), and demonstrated that practicing these activities imparts a clear advantage in in-plane body rotation performance. Other athletes, such as handball and soccer players, whose activities do require body rotations may have more experience with in-depth rotations. The present study examined the effect of two components that are differently solicited in sport practices on the mental rotation ability: the rotation axis (in-plane, in-depth) and the predominantly used limb (arms, legs). Handball players, soccer players, and gymnasts were asked to rotate handball and soccer strike images mentally, which were presented in different in-plane and in-depth orientations. The results revealed that handball and soccer players performed the in-depth rotations faster than in-plane rotations; however, the two rotation axes did not differ in gymnasts. In addition, soccer players performed the mental rotations of handball strike images slower. Our findings suggest that the development of mental rotation tasks that involve the major components of a physical activity allows and is necessary for specifying the links between this activity and the mental rotation performance. PMID:25064695

  5. Metasurface external cavity laser

    NASA Astrophysics Data System (ADS)

    Xu, Luyao; Curwen, Christopher A.; Hon, Philip W. C.; Chen, Qi-Sheng; Itoh, Tatsuo; Williams, Benjamin S.

    2015-11-01

    A vertical-external-cavity surface-emitting-laser is demonstrated in the terahertz range, which is based upon an amplifying metasurface reflector composed of a sub-wavelength array of antenna-coupled quantum-cascade sub-cavities. Lasing is possible when the metasurface reflector is placed into a low-loss external cavity such that the external cavity—not the sub-cavities—determines the beam properties. A near-Gaussian beam of 4.3° × 5.1° divergence is observed and an output power level >5 mW is achieved. The polarized response of the metasurface allows the use of a wire-grid polarizer as an output coupler that is continuously tunable.

  6. Metasurface external cavity laser

    SciTech Connect

    Xu, Luyao Curwen, Christopher A.; Williams, Benjamin S.; Hon, Philip W. C.; Itoh, Tatsuo; Chen, Qi-Sheng

    2015-11-30

    A vertical-external-cavity surface-emitting-laser is demonstrated in the terahertz range, which is based upon an amplifying metasurface reflector composed of a sub-wavelength array of antenna-coupled quantum-cascade sub-cavities. Lasing is possible when the metasurface reflector is placed into a low-loss external cavity such that the external cavity—not the sub-cavities—determines the beam properties. A near-Gaussian beam of 4.3° × 5.1° divergence is observed and an output power level >5 mW is achieved. The polarized response of the metasurface allows the use of a wire-grid polarizer as an output coupler that is continuously tunable.

  7. Arbuscular mycorrhizal fungal diversity, root colonization, and soil alkaline phosphatase activity in response to maize-wheat rotation and no-tillage in North China.

    PubMed

    Hu, Junli; Yang, Anna; Zhu, Anning; Wang, Junhua; Dai, Jue; Wong, Ming Hung; Lin, Xiangui

    2015-07-01

    Monitoring the effects of no-tillage (NT) in comparison with conventional tillage (CT) on soil microbes could improve our understanding of soil biochemical processes and thus help us to develop sound management strategies. The objective of this study was to compare the species composition and ecological function of soil arbuscular mycorrhizal (AM) fungi during the growth and rotation of crops under NT and CT. From late June 2009 to early June 2010, 32 topsoil (0-15 cm) samples from four individual plots per treatment (CT and NT) were collected at both the jointing and maturation stages of maize (Zea mays L.) and wheat (Triticum aestivum L.) from a long-term experimental field that was established in an Aquic Inceptisol in North China in June 2006. The AM fungal spores were isolated and identified and then used to calculate species diversity indices, including the Shannon- Wiener index (H'), Evenness (E), and Simpson's index (D). The root mycorrhizal colonization and soil alkaline phosphatase activity were also determined. A total of 34 species of AM fungi within nine genera were recorded. Compared with NT, CT negatively affected the soil AM fungal community at the maize sowing stage, leading to decreases in the average diversity indices (from 2.12, 0.79, and 0.82 to 1.79, 0.72, and 0.74 for H', E, and D, respectively), root mycorrhizal colonization (from 28% to 20%), soil alkaline phosphatase activity (from 0.24 to 0.19 mg/g/24 h) and available phosphorus concentration (from 17.4 to 10.5 mg/kg) at the maize jointing stage. However, reductions in diversity indices of H', E, and D were restored to 2.20, 0.81, and 0.84, respectively, at the maize maturation stage. CT should affect the community again at the wheat sowing stage; however, a similar restoration in the species diversity of AM fungi was completed before the wheat jointing stage, and the highest Jaccard index (0.800) for similarity in the species composition of soil AM fungi between CT and NT was recorded at

  8. Arbuscular mycorrhizal fungal diversity, root colonization, and soil alkaline phosphatase activity in response to maize-wheat rotation and no-tillage in North China.

    PubMed

    Hu, Junli; Yang, Anna; Zhu, Anning; Wang, Junhua; Dai, Jue; Wong, Ming Hung; Lin, Xiangui

    2015-07-01

    Monitoring the effects of no-tillage (NT) in comparison with conventional tillage (CT) on soil microbes could improve our understanding of soil biochemical processes and thus help us to develop sound management strategies. The objective of this study was to compare the species composition and ecological function of soil arbuscular mycorrhizal (AM) fungi during the growth and rotation of crops under NT and CT. From late June 2009 to early June 2010, 32 topsoil (0-15 cm) samples from four individual plots per treatment (CT and NT) were collected at both the jointing and maturation stages of maize (Zea mays L.) and wheat (Triticum aestivum L.) from a long-term experimental field that was established in an Aquic Inceptisol in North China in June 2006. The AM fungal spores were isolated and identified and then used to calculate species diversity indices, including the Shannon- Wiener index (H'), Evenness (E), and Simpson's index (D). The root mycorrhizal colonization and soil alkaline phosphatase activity were also determined. A total of 34 species of AM fungi within nine genera were recorded. Compared with NT, CT negatively affected the soil AM fungal community at the maize sowing stage, leading to decreases in the average diversity indices (from 2.12, 0.79, and 0.82 to 1.79, 0.72, and 0.74 for H', E, and D, respectively), root mycorrhizal colonization (from 28% to 20%), soil alkaline phosphatase activity (from 0.24 to 0.19 mg/g/24 h) and available phosphorus concentration (from 17.4 to 10.5 mg/kg) at the maize jointing stage. However, reductions in diversity indices of H', E, and D were restored to 2.20, 0.81, and 0.84, respectively, at the maize maturation stage. CT should affect the community again at the wheat sowing stage; however, a similar restoration in the species diversity of AM fungi was completed before the wheat jointing stage, and the highest Jaccard index (0.800) for similarity in the species composition of soil AM fungi between CT and NT was recorded at

  9. A microscale thermophoretic turbine driven by external diffusive heat flux

    NASA Astrophysics Data System (ADS)

    Yang, Mingcheng; Liu, Rui; Ripoll, Marisol; Chen, Ke

    2014-10-01

    We propose a theoretical prototype of a micro-scale turbine externally driven by diffusive heat flux without the need for macroscopic particle flux, which is in sharp contrast to conventional turbines. The prototypes are described analytically and validated by computer simulations. Our results indicate that a micro-scale turbine composed of anisotropic blades can rotate unidirectionally in an external temperature gradient due to the anisotropic thermophoresis effect. The rotational direction and speed depend on the temperature gradient, the geometry and the thermophoretic properties of the turbine. The proposed thermophoretic turbines can be experimentally realized and implemented on micro-devices such as computer-chips to recover waste heat or to facilitate cooling.We propose a theoretical prototype of a micro-scale turbine externally driven by diffusive heat flux without the need for macroscopic particle flux, which is in sharp contrast to conventional turbines. The prototypes are described analytically and validated by computer simulations. Our results indicate that a micro-scale turbine composed of anisotropic blades can rotate unidirectionally in an external temperature gradient due to the anisotropic thermophoresis effect. The rotational direction and speed depend on the temperature gradient, the geometry and the thermophoretic properties of the turbine. The proposed thermophoretic turbines can be experimentally realized and implemented on micro-devices such as computer-chips to recover waste heat or to facilitate cooling. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03990d

  10. Ergonomics and biology of spinal rotation.

    PubMed

    Kumar, Shrawan

    2004-03-15

    Spinal rotation, though being a very common motion of the body, is poorly understood. Furthermore, this motion and the extent of its development is unique to the human. Beyond the extent of its need in common activities, spinal rotation is a destabilizating motion for an inherently unstable structure. Spinal rotation has been argued to be an essential feature for an efficient bipedal gait. Also, it provides leverage to the upper extremities in delivering a forceful impact. An artificial restriction/elimination of spinal rotation resulted in significantly shorter stride length, slower walking velocity, and higher energy consumption in walking (p < 0.05). Spinal rotation also decreases the amount of force the spinal muscles can generate (to 25% of spinal extension). However, its extensive employment in industrial activities has been associated with 60.4% of back injuries. It is further stated that the amount of scientific information currently available is inadequate to biomechanically model the spinal response in a working environment. For example, when the spine is pre-rotated, a further rotation in the direction of pre-rotation decreases the force production significantly (p < 0.01) and increases the EMG activity significantly (p < 0.01) but the pattern changes with effort in the opposite direction. This and other properties (described in the paper) render biomechanical models inadequate. Muscle activation pattern and neuromotor behaviour of spinal muscles in flexion/extension and rotation of the spine are significantly different from each other (p < 0.01). The localized fatigue in different spinal muscles in the same contraction is significantly different and has been called differential fatigue. Finally, the trunk rotation, being pivotal for bipedal locomotion has brought many back problems to the human race.

  11. Non-Newtonian rotational swimming: experiments

    NASA Astrophysics Data System (ADS)

    Gomez, S.; Godinez, F. A.; Zenit, R.; Lauga, E.

    2013-11-01

    Recently Pak et al. (PoF, 2012) showed that a device composed of two unequal spheres (snowman) could swim in a viscoelastic fluid under a rotational actuation. By symmetry such device isn't able to move in a Newtonian fluid but because of its geometrical asymmetry is able to generate asymmetric elastic response and generate a purely viscoelastic thrust. We implemented this swimmer experimentally using a magnetic snowman driven by an external rotating magnetic field. We demonstrate that the snowman swims solely as a result of fluid elasticity. We conduct tests in Newtonian and Boger fluids, varying the sphere size ratio and rotation speed. We also conducted measurements in a confined environment, which showed an improved swimming performance.

  12. Literature: External Forms.

    ERIC Educational Resources Information Center

    Regional Curriculum Project, Atlanta, GA.

    This curriculum guide, developed as part of a total English curriculum for pre-kindergarten through grade 10, suggests that students can best understand literature by understanding its recurring external forms or genres, and includes (1) an overview describing the four literary genres of drama, narrative poetry, narrative fiction, and lyric poetry…

  13. External Environmental Forecast.

    ERIC Educational Resources Information Center

    Lapin, Joel D.

    Representing current viewpoints of academics, futures experts, and social observers, this external environmental forecast presents projections and information of particular relevance to the future of Catonsville Community College. The following topics are examined: (1) population changes and implications for higher education; (2) state and local…

  14. External Otitis (Swimmer's Ear)

    MedlinePlus

    ... drops, keeping water out of the ear, and pain relievers are the most common forms of treatment. External otitis may involve the entire canal, as ... does not allow fungus to grow as well. Treatment of boils depends on ... relievers, such as oxycodone with acetaminophen , can be given ...

  15. Balance in a rotating artificial gravity environment

    NASA Technical Reports Server (NTRS)

    Soeda, Kazuhiro; DiZio, Paul; Lackner, James R.

    2003-01-01

    When subjects stand at the center of a fully enclosed room that is rotating at constant velocity, their natural postural sway generates Coriolis forces that destabilize their center of mass and head. We quantitatively assessed how exposure to constant velocity rotation at 10 rpm affected postural control. Twelve subjects stood in a heel-to-toe stance in the rotating room. Each test session involved three phases: (1) pre-rotation, (2) per-rotation, and (3) post-rotation. In each phase, subjects were tested in both eyes open and eyes closed conditions. Four measures were used to characterize center of mass movement and head movement: mean sway amplitude, total power, mean power frequency, and frequency of maximum power. Each measure was computed for anterior-posterior and medial-lateral sway. Both anterior-posterior and medial-lateral head and center of mass sway during rotation had significantly greater mean sway amplitude and total power compared with pre- and post-rotation values. Mean power frequency and frequency of maximum power were little affected. Eyes open conditions were significantly more stable in all test phases than eyes-closed, but vision did not completely suppress the effects of rotation. The greatest effect of rotation was in the eyes-closed condition with mean sway amplitude and total power increasing more than twofold. Inverted pendulum sway was maintained in all phases of both test conditions. No aftereffects of rotation were present after the four 25-s exposures each subject received. We expect that with longer exposure periods and with active generation of body sway subjects would both adapt to rotation and exhibit post-rotary aftereffects.

  16. Global Rotation of Non-Rotating Origin

    NASA Astrophysics Data System (ADS)

    Fukushima, T.

    2001-11-01

    At its 24th General Assembly held at Manchester last year, the IAU has adopted the Celestial Ephemeris Origin (CEO) as a new longitude origin of the celestial coordinate system (Capitaine et al. 2000, IAU 2001). The CEO is the application of Guinot's non-rotating origin (NRO) to the Earth's equator (Guinot 1979, Capitaine et al. 1986, Capitaine 1990). By using the current IAU precession/nutation theory, we integrated the global orbit of CEO. It is a slightly curved zigzag pattern of the amplitude of around 23o moving secularly along the ecliptic. Among its kinematical features, we note that CEO has a large secular component of rotation with respect to the inertial reference frame. The current speed of this global rotation is as large as around -4.15 ''/yr. The negative sign shows that CEO rotates clockwise with respect to the inertial frame when viewed from the north celestial pole. Unfortunately this is a general property of NROs. On the other hand, such secular rotation does not exist for some geometrically-defined longitude origins like K, H, and Σ already discussed in Kovalevsky and McCarthy (1998). We think that the existence of a global secular rotaion means that the CEO, and NROs in general, is not appropriate to be specified as the x-axis of celestial coordinate systems.

  17. Experimental studies of turbulence lifetimes in differentially rotating flows

    NASA Astrophysics Data System (ADS)

    Edlund, E. M.; Yan, Z.; Spence, E. J.; Roach, A. H.; Rhoads, J.; Ji, H.

    2012-11-01

    Inference of accretion rates from observations of stellar systems suggests inward mass fluxes which can only be reasonably explained by a turbulent transport process. While the magneto-rotational instability (MRI) is likely active in systems above a critical ionization, there remains some question as to whether the MRI can be active in cooler bodies such as proto-planetary systems, and if not, what mechanism is then responsible for angular momentum transport? Keplerian rotation profiles are hydrodynamically linearly stable in the inviscid limit, however, it is not known if there exists a subcritical transition. A series of studies in the Hydrodynamic Turbulence Experiment (HTX), a modified Taylor-Couette device, have explored quiescent flows in the quasi-Keplerian regime. Operating in the wide-gap limit and with split axial boundaries to control the Ekman circulation, azimuthal flows in HTX can be brought very close to ideal Couette. These flows are subjected to external perturbations to test their ability to sustain incompressible hydrodynamic turbulence. Under no circumstances has a subcritical transition to turbulence been observed. Turbulence decay lifetimes are measured and compared to theoretical models.

  18. Asteroid rotation rates

    NASA Technical Reports Server (NTRS)

    Dermott, S. F.; Harris, A. W.; Murray, C. D.

    1984-01-01

    A trend of increasing mean rotational frequency with increasing diameter is noted in asteroids with diameters greater than 120 km, irrespective of M-, S-, and C-type asteroid subset and family or nonfamily membership. This trend cannot be accounted for by observational selection. For asteroids with diameters smaller than 120 km mean rotational frequency increases with decreasing diameter, but within this group there is a subset with exceptionally long rotational periods. This marked change in the distribution at 120-km diameter could separate primordial asteroids from their collision products. It is also noted that, for asteroids of a given diameter, M asteroids rotate faster than S asteroids, which in turn rotate faster than C asteroids. For all types, family members rotate faster than nonfamily members.

  19. Combined Solar system and rotation curve constraints on MOND

    NASA Astrophysics Data System (ADS)

    Hees, Aurélien; Famaey, Benoit; Angus, Garry W.; Gentile, Gianfranco

    2016-01-01

    The Modified Newtonian Dynamics (MOND) paradigm generically predicts that the external gravitational field in which a system is embedded can produce effects on its internal dynamics. In this communication, we first show that this external field effect (EFE) can significantly improve some galactic rotation curves fits by decreasing the predicted velocities of the external part of the rotation curves. In modified gravity versions of MOND, this EFE also appears in the Solar system and leads to a very good way to constrain the transition function of the theory. A combined analysis of the galactic rotation curves and Solar system constraints (provided by the Cassini spacecraft) rules out several classes of popular MOND transition functions, but leaves others viable. Moreover, we show that Laser Interferometer Space Antenna Pathfinder will not be able to improve the current constraints on these still viable transition functions.

  20. Analysis of the Earth's variable rotation

    NASA Technical Reports Server (NTRS)

    Chao, B. F.

    1984-01-01

    The objective was to analyze the Earth's rotation, and to compare the observations with the atmospheric and seismic excitation functions. The variation in the Earth's rotation can be separated into the length-of-day (LOD) variation and the polar motion. Possible driving mechanisms include: atmospheric/oceanic circulations, seismic activities, solar-lunar tides, mantle convection, core-mantle coupling, and solar activities. The major problem of concern was the identification of these dynamical processes as primary driving mechanisms for the various features in the variation of the Earth's rotation.

  1. The spatial rotator.

    PubMed

    Rasmusson, A; Hahn, U; Larsen, J O; Gundersen, H J G; Jensen, E B Vedel; Nyengaard, J R

    2013-05-01

    This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making the spatial rotator fast to use. Since a 3D probe is involved, it is expected that the spatial rotator will be more efficient than the the nucleator and the planar rotator, which are based on measurements in a single plane. An extensive simulation study shows that the spatial rotator may be more efficient than the traditional local volume estimators. Furthermore, the spatial rotator can be seen as a further development of the Cavalieri estimator, which does not require randomization of sectioning or viewing direction. The tissue may thus be sectioned in any arbitrary direction, making it easy to identify the specific tissue region under study. In order to use the spatial rotator in practice, however, it is necessary to be able to identify intersection points between cell boundaries and test rays in a series of parallel focal planes, also at the peripheral parts of the cell boundaries. In cases where over- and underprojection phenomena are not negligible, they should therefore be corrected for if the spatial rotator is to be applied. If such a correction is not possible, it is needed to avoid these phenomena by using microscopy with increased resolution in the focal plane. PMID:23488880

  2. The flexion-extension axis of the knee and its relationship to the rotational orientation of the tibial plateau.

    PubMed

    Lawrie, Charles M; Noble, Philip C; Ismaily, Sabir K; Stal, Drew; Incavo, Steve J

    2011-09-01

    We measured the optimal rotational alignment of the tibial component with respect to anatomic landmarks. Kinematic data were collected from functional maneuvers simulated in 20 cadaveric knees mounted in a joint simulator. The axis of knee motion was calculated for squatting and lunging activities over the interval of 30° to 90° of knee flexion. We then examined the accuracy and variability of 5 different anatomic axes in predicting the direction of knee motion. No one landmark guaranteed correct alignment of the tibial component and most predictors were highly variable (range, 6°-21°). The most accurate indicators were the medial third of the tibial tubercle (average error: squatting: 3.5° external rotation; lunging: 9.5°), and the medial-lateral axis of the resected tibial surface (6.7° and 1.1° internal rotation). The correct alignment of the tibial component can be best achieved by splitting the difference between these landmarks to eliminate placement of the component in excessive external and excessive internal rotation.

  3. [The external quality assessment schemes for lead in blood organized by the French national agency for medicine and health product safety: a synthesis of 15 years of activity].

    PubMed

    Pineau, Alain; Otz, Jocelyne; Guillard, Olivier; Fauconneau, Bernard; Dumont, Gilles; François-Burg, Elisabeth

    2014-01-01

    In 1992, at the request of the French labor ministry following questions on the ability of medical biology laboratories to satisfactorily measure blood lead level (PbB), a national PbB quality control came into being. Only in 1996 did this external quality control include a number of laboratories sufficient to allow for a significant retrospective evaluation. After fifteen years (1996-2011), The French National Agency for Medicines and Health Products Safety wished to exploit the database collected. The number of participating laboratories went down from 73 to 41. On the other hand, the key finding pertained to the highly improved performance of the laboratories, which was associated with a spread decrease of the results over the entire range of tested PbBs (9 to 700 μg/L). Since 2006, we have observed increasing use of the inductively coupled plasma with mass spectrometry and decreasing use of electrothermal atomic absorption spectrometry. Provided that they rely on identical metrology expertise, the two analytical techniques lead to results on all the tested concentrations that are not statistically different. PMID:24492097

  4. [The external quality assessment schemes for lead in blood organized by the French national agency for medicine and health product safety: a synthesis of 15 years of activity].

    PubMed

    Pineau, Alain; Otz, Jocelyne; Guillard, Olivier; Fauconneau, Bernard; Dumont, Gilles; François-Burg, Elisabeth

    2014-01-01

    In 1992, at the request of the French labor ministry following questions on the ability of medical biology laboratories to satisfactorily measure blood lead level (PbB), a national PbB quality control came into being. Only in 1996 did this external quality control include a number of laboratories sufficient to allow for a significant retrospective evaluation. After fifteen years (1996-2011), The French National Agency for Medicines and Health Products Safety wished to exploit the database collected. The number of participating laboratories went down from 73 to 41. On the other hand, the key finding pertained to the highly improved performance of the laboratories, which was associated with a spread decrease of the results over the entire range of tested PbBs (9 to 700 μg/L). Since 2006, we have observed increasing use of the inductively coupled plasma with mass spectrometry and decreasing use of electrothermal atomic absorption spectrometry. Provided that they rely on identical metrology expertise, the two analytical techniques lead to results on all the tested concentrations that are not statistically different.

  5. Getting drowned in a swirl: Deformable bead-spring model microswimmers in external flow fields

    NASA Astrophysics Data System (ADS)

    Küchler, Niklas; Löwen, Hartmut; Menzel, Andreas M.

    2016-02-01

    Deformability is a central feature of many types of microswimmers, e.g., for artificially generated self-propelled droplets. Here, we analyze deformable bead-spring microswimmers in an externally imposed solvent flow field as simple theoretical model systems. We focus on their behavior in a circular swirl flow in two spatial dimensions. Linear (straight) two-bead swimmers are found to circle around the swirl with a slight drift to the outside with increasing activity. In contrast to that, we observe for triangular three-bead or squarelike four-bead swimmers a tendency of being drawn into the swirl and finally getting drowned, although a radial inward component is absent in the flow field. During one cycle around the swirl, the self-propulsion direction of an active triangular or squarelike swimmer remains almost constant, while their orbits become deformed exhibiting an "egglike" shape. Over time, the swirl flow induces slight net rotations of these swimmer types, which leads to net rotations of the egg-shaped orbits. Interestingly, in certain cases, the orbital rotation changes sense when the swimmer approaches the flow singularity. Our predictions can be verified in real-space experiments on artificial microswimmers.

  6. [Wearable Automatic External Defibrillators].

    PubMed

    Luo, Huajie; Luo, Zhangyuan; Jin, Xun; Zhang, Leilei; Wang, Changjin; Zhang, Wenzan; Tu, Quan

    2015-11-01

    Defibrillation is the most effective method of treating ventricular fibrillation(VF), this paper introduces wearable automatic external defibrillators based on embedded system which includes EGG measurements, bioelectrical impedance measurement, discharge defibrillation module, which can automatic identify VF signal, biphasic exponential waveform defibrillation discharge. After verified by animal tests, the device can realize EGG acquisition and automatic identification. After identifying the ventricular fibrillation signal, it can automatic defibrillate to abort ventricular fibrillation and to realize the cardiac electrical cardioversion.

  7. Externally triggered microcapsules

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor); Mosier, Benjamin (Inventor)

    2011-01-01

    Disclosed are microcapsules comprising a polymer shell enclosing one or more immiscible liquid phases in which a drug or drug precursor are contained in a liquid phase. The microparticles also contain magnetic particles that can be heated by application of an external magnetic field and thus heated to a predetermined Curie temperature. Heating of the particles melts the polymer shell and releases the drug without causing heating of surrounding tissues.

  8. The Gaia-ESO Survey: A lithium-rotation connection at 5 Myr?

    NASA Astrophysics Data System (ADS)

    Bouvier, J.; Lanzafame, A. C.; Venuti, L.; Klutsch, A.; Jeffries, R.; Frasca, A.; Moraux, E.; Biazzo, K.; Messina, S.; Micela, G.; Randich, S.; Stauffer, J.; Cody, A. M.; Flaccomio, E.; Gilmore, G.; Bayo, A.; Bensby, T.; Bragaglia, A.; Carraro, G.; Casey, A.; Costado, M. T.; Damiani, F.; Delgado Mena, E.; Donati, P.; Franciosini, E.; Hourihane, A.; Koposov, S.; Lardo, C.; Lewis, J.; Magrini, L.; Monaco, L.; Morbidelli, L.; Prisinzano, L.; Sacco, G.; Sbordone, L.; Sousa, S. G.; Vallenari, A.; Worley, C. C.; Zaggia, S.; Zwitter, T.

    2016-05-01

    Context. The evolution of lithium abundance in cool dwarfs provides a unique probe of nonstandard processes in stellar evolution. Aims: We investigate the lithium content of young low-mass stars in the 5 Myr old, star forming region NGC 2264 and its relationship with rotation. Methods: We combine lithium equivalent width measurements (EW(Li)) from the Gaia-ESO Survey with the determination of rotational periods from the CSI 2264 survey. We only consider bona fide nonaccreting cluster members to minimize the uncertainties on EW(Li). Results: We report the existence of a relationship between lithium content and rotation in NGC 2264 at an age of 5 Myr. The Li-rotation connection is seen over a restricted temperature range (Teff = 3800-4400 K), where fast rotators are Li-rich compared to slow rotators. This correlation is similar to, albeit of lower amplitude than, the Li-rotation connection previously reported for K dwarfs in the 125 Myr old Pleiades cluster. We investigate whether the nonstandard pre-main-sequence models developed so far to explain the Pleiades results, which are based on episodic accretion, pre-main-sequence, core-envelope decoupling, and/or radius inflation due to enhanced magnetic activity, can account for early development of the Li-rotation connection. While radius inflation appears to be the most promising possibility, each of these models has issues. We therefore also discuss external causes that might operate during the first few Myr of pre-main-sequence evolution, such as planet engulfment and/or steady disk accretion, as possible candidates for the common origin for Li excess and fast rotation in young low-mass pre-main-sequence stars. Conclusions: The emergence of a connection between lithium content and rotation rate at such an early age as 5 Myr suggests a complex link between accretion processes, early angular momentum evolution, and possibly planet formation, which likely impacts early stellar evolution and has yet to be fully

  9. Effect of carbon taxes and subsidies on optimal forest rotation age and supply of carbon services

    SciTech Connect

    Kooten, G.C. van; Binkley, C.S.; Delcourt, G.

    1995-05-01

    Carbon taxes and subsidies will affect the optimal forest rotation and, consequently, the carbon stored in forests. Unlike the Hartman rotation, where externality benefits are a function of the volume of timber growing on a site at any time, carbon benefits are a function of the change in biomass. Theoretical and empirical results (for coastal British Columbia and northern Alberta) indicate that, under some tax regimes, it may be socially optimal never to harvest the trees. In general, inclusion of the external benefits from carbon uptake results in rotation ages only a bit longer than the financial (Faustmann) rotation age. 27 refs., 2 figs., 2 tabs.

  10. Not all anxious individuals get lost: Trait anxiety and mental rotation ability interact to explain performance in map-based route learning in men.

    PubMed

    Thoresen, John C; Francelet, Rebecca; Coltekin, Arzu; Richter, Kai-Florian; Fabrikant, Sara I; Sandi, Carmen

    2016-07-01

    Navigation through an environment is a fundamental human activity. Although group differences in navigational ability are documented (e.g., gender), little is known about traits that predict these abilities. Apart from a well-established link between mental rotational abilities and navigational learning abilities, recent studies point to an influence of trait anxiety on the formation of internal cognitive spatial representations. However, it is unknown whether trait anxiety affects the processing of information obtained through externalized representations such as maps. Here, we addressed this question by taking into account emerging evidence indicating impaired performance in executive tasks by high trait anxiety specifically in individuals with lower executive capacities. For this purpose, we tested 104 male participants, previously characterised on trait anxiety and mental rotation ability, on a newly-designed map-based route learning task, where participants matched routes presented dynamically on a city map to one presented immediately before (same/different judgments). We predicted an interaction between trait anxiety and mental rotation ability, specifically that performance in the route learning task would be negatively affected by anxiety in participants with low mental rotation ability. Importantly, and as predicted, an interaction between anxiety and mental rotation ability was observed: trait anxiety negatively affected participants with low-but not high-mental rotation ability. Our study reveals a detrimental role of trait anxiety in map-based route learning and specifies a disadvantage in the processing of map representations for high-anxious individuals with low mental rotation abilities.

  11. Not all anxious individuals get lost: Trait anxiety and mental rotation ability interact to explain performance in map-based route learning in men.

    PubMed

    Thoresen, John C; Francelet, Rebecca; Coltekin, Arzu; Richter, Kai-Florian; Fabrikant, Sara I; Sandi, Carmen

    2016-07-01

    Navigation through an environment is a fundamental human activity. Although group differences in navigational ability are documented (e.g., gender), little is known about traits that predict these abilities. Apart from a well-established link between mental rotational abilities and navigational learning abilities, recent studies point to an influence of trait anxiety on the formation of internal cognitive spatial representations. However, it is unknown whether trait anxiety affects the processing of information obtained through externalized representations such as maps. Here, we addressed this question by taking into account emerging evidence indicating impaired performance in executive tasks by high trait anxiety specifically in individuals with lower executive capacities. For this purpose, we tested 104 male participants, previously characterised on trait anxiety and mental rotation ability, on a newly-designed map-based route learning task, where participants matched routes presented dynamically on a city map to one presented immedi