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Sample records for ciliary beat frequency

  1. Automatic analysis of ciliary beat frequency using optical flow

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    Figl, Michael; Lechner, Manuel; Werther, Tobias; Horak, Fritz; Hummel, Johann; Birkfellner, Wolfgang

    2012-02-01

    Ciliary beat frequency (CBF) can be a useful parameter for diagnosis of several diseases, as e.g. primary ciliary dyskinesia. (PCD). CBF computation is usually done using manual evaluation of high speed video sequences, a tedious, observer dependent, and not very accurate procedure. We used the OpenCV's pyramidal implementation of the Lukas-Kanade algorithm for optical flow computation and applied this to certain objects to follow the movements. The objects were chosen by their contrast applying the corner detection by Shi and Tomasi. Discrimination between background/noise and cilia by a frequency histogram allowed to compute the CBF. Frequency analysis was done using the Fourier transform in matlab. The correct number of Fourier summands was found by the slope in an approximation curve. The method showed to be usable to distinguish between healthy and diseased samples. However there remain difficulties in automatically identifying the cilia, and also in finding enough high contrast cilia in the image. Furthermore the some of the higher contrast cilia are lost (and sometimes found) by the method, an easy way to distinguish the correct sub-path of a point's path have yet to be found in the case where the slope methods doesn't work.

  2. Measurement of ciliary beat frequency using Doppler optical coherence tomography.

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    Lemieux, Bryan T; Chen, Jason J; Jing, Joseph; Chen, Zhongping; Wong, Brian J F

    2015-11-01

    Measuring ciliary beat frequency (CBF) is a technical challenge and difficult to perform in vivo. Doppler optical coherence tomography (D-OCT) is a mesoscopic noncontact imaging modality that provides high-resolution tomographic images and detects micromotion simultaneously in living tissues. In this work we used D-OCT to measure CBF in ex vivo tissue as the first step toward translating this technology to clinical use. Fresh ex vivo samples of rabbit tracheal mucosa were imaged using both D-OCT and phase-contrast microscopy (n = 5). The D-OCT system was designed and built to specification in our lab (1310-nm swept source vertical-cavity surface-emitting laser [VCSEL], 6-μm axial resolution). The samples were placed in culture and incubated at 37°C. A fast Fourier transform was performed on the D-OCT signal recorded on the surface of the samples to gauge CBF. High-speed digital video of the epithelium recorded via phase-contrast microscopy was analyzed to confirm the CBF measurements. The D-OCT system detected Doppler signal at the epithelial layer of ex vivo rabbit tracheal samples suggestive of ciliary motion. CBF was measured at 9.36 ± 1.22 Hz using D-OCT and 9.08 ± 0.48 Hz using phase-contrast microscopy. No significant differences were found between the 2 methods (p > 0.05). D-OCT allows for the quantitative measurement of CBF without the need to resolve individual cilia. Furthermore, D-OCT technology can be incorporated into endoscopic platforms that allow clinicians to readily measure CBF in the office and provide a direct measurement of mucosal health. © 2015 ARS-AAOA, LLC.

  3. Influence of essential and fatty oils on ciliary beat frequency of human nasal epithelial cells.

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    Neher, Andreas; Gstöttner, Michaela; Thaurer, Michael; Augustijns, Patrick; Reinelt, Monika; Schobersberger, Wolfgang

    2008-01-01

    In alternative and complementary medicine, the use of essential and fatty oils has become more and more popular. In addition to conventional medical therapies, self-medication is showing increasing popularity, using agents with unclear compounds and poorly controlled dosages. Among other disorders, these alternative treatments are used in bronchitis and rhinitis, including some topical applications. Thus, the influence on ciliated epithelia should be evaluated, because a disturbance of the ciliary function can lead to recurrent sinusitis and chronic rhinosinusitis. The aim of this study was to test the influence of fatty and essential oils on the ciliary beat frequency (CBF) of nasal mucosa in vivo. The influence of sesame oil, soy oil, peanut oil, Miglyol 840, thyme oil, lavender oil, eucalyptus oil, and menthol on the ciliary activity of nasal brushings was evaluated by digital high-speed imaging. The presence of most fatty oils resulted in an increase in CBF, the effect being highest for peanut oil. Miglyol 840 had no significant influence on CBF. The essential oils were tested at a concentration of 0.2 and 2%. Thyme oil did not affect CBF, whereas the presence of all other essentials oils resulted in an increase in CBF; the effect was higher at 0.2% than at 2%. Except thyme oil and Miglyol 840, all tested oils caused an increase in CBF. Interestingly, the 0.2% concentrations of essential oils resulted in stronger effects when compared with the 2% concentrations.

  4. Safety assessment of thiolated polymers: effect on ciliary beat frequency in human nasal epithelial cells.

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    Palmberger, Thomas F; Augustijns, Patrick; Vetter, Anja; Bernkop-Schnürch, Andreas

    2011-12-01

    The aim of this study was to investigate the nasal safety of gel formulations of thiolated polymers (thiomers) by assessing their effect on ciliary beat frequency (CBF) in human nasal epithelial cells. Poly(acrylic acid) 450 kDa-cysteine (PAA-cys) and alginate-cysteine (alg-cys) were synthesized by covalent attachment of L-cysteine to the polymeric backbone. The cationic polymer chitosan-thiobutylamidine (chito-TBA) was synthesized by attaching iminothiolane to chitosan. CBF using was measured by a photometric system. CBF was measured before incubating the cells with test gels, during incubation and after washing out the polymeric test gels to evaluate reversibility of cilio-inhibition. The influence of viscosity on CBF was determined by using hydroxyethylcellulose (HEC)-gels of various concentrations. Ciliary beating was observed to be affected by viscosity, but cilia were still beating in the presence of a HEC-gel displaying an apparent viscosity of 25 Pa.s. In case of thiolated polymers and their unmodified control, a concentration-dependent decrease in CBF could be observed. PAA-cys, alg-cys, chito-TBA and their corresponding unmodified controls exhibited a moderate cilio-inhibitory effect, followed by a partial recovery of CBF when used at a concentration of 1%. Alg-cys 2% and chito-TBA 2% (m/v) gels exhibited severe cilio-inhibition, which was partially reversible. L-cysteine and reduced glutathione led to mild cilio-inhibition at concentrations of 3% (m/v). Taking into account that dilution after application and cilio-modifying effects is usually more pronounced under in vitro conditions, thiomers can be considered as suitable excipients for nasal drug delivery systems.

  5. Effects of perfluorooctane sulfonate on tracheal ciliary beating frequency in mice

    International Nuclear Information System (INIS)

    Matsubara, Eriko; Nakahari, Takashi; Yoshida, Hideyo; Kuroiwa, Toshihiko; Harada, Kouji H.; Inoue, Kayoko; Koizumi, Akio

    2007-01-01

    Perfluorooctane sulfonate (PFOS) is one of the emerging persistent organic pollutants, ubiquitously found in the global environment, even in human serum. PFOS has been reported to perturb Ca 2+ homeostasis in Paramecium, cardiomyocytes and neurons. Since ciliary beat frequency (CBF) in the trachea is known to be increased by cytoplasmic Ca 2+ elevation, the effects of PFOS on CBF were evaluated in a slice preparation using video-enhanced contrast microscopy. PFOS increased CBF by 11% (P 2+ concentration ([Ca 2+ ] i ) in mouse tracheal ciliary cells. In Ca 2+ -free solution, PFOS at 100 μM failed to increase CBF (0.96-fold of vehicle control). The addition of Gd 3+ (1 μM), a store-operated Ca 2+ channel blocker, did not prevent the increase in CBF (1.09-fold (P + concentration (50 mM), which causes depolarization of the plasma membrane potential and a transient increase in [Ca 2+ ] i , increased CBF by 20% (P 2+ channels (VDCCs) in stimulation of CBF. Nifedipine (30 μM), a selective VDCC blocker, antagonized the effects of high K + (0.92-fold of high K + solution) and PFOS (0.96-fold of vehicle control) on CBF. In cells from peroxisome proliferator-activated receptor α (PPARα)-null mice, PFOS still increased CBF (1.12-fold (P 2+ through VDCC

  6. An Automated Measurement of Ciliary Beating Frequency using a Combined Optical Flow and Peak Detection.

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    Kim, Woojae; Han, Tae Hwa; Kim, Hyun Jun; Park, Man Young; Kim, Ku Sang; Park, Rae Woong

    2011-06-01

    The mucociliary transport system is a major defense mechanism of the respiratory tract. The performance of mucous transportation in the nasal cavity can be represented by a ciliary beating frequency (CBF). This study proposes a novel method to measure CBF by using optical flow. To obtain objective estimates of CBF from video images, an automated computer-based image processing technique is developed. This study proposes a new method based on optical flow for image processing and peak detection for signal processing. We compare the measuring accuracy of the method in various combinations of image processing (optical flow versus difference image) and signal processing (fast Fourier transform [FFT] vs. peak detection [PD]). The digital high-speed video method with a manual count of CBF in slow motion video play, is the gold-standard in CBF measurement. We obtained a total of fifty recorded ciliated sinonasal epithelium images to measure CBF from the Department of Otolaryngology. The ciliated sinonasal epithelium images were recorded at 50-100 frames per second using a charge coupled device camera with an inverted microscope at a magnification of ×1,000. The mean square errors and variance for each method were 1.24, 0.84 Hz; 11.8, 2.63 Hz; 3.22, 1.46 Hz; and 3.82, 1.53 Hz for optical flow (OF) + PD, OF + FFT, difference image [DI] + PD, and DI + FFT, respectively. Of the four methods, PD using optical flow showed the best performance for measuring the CBF of nasal mucosa. The proposed method was able to measure CBF more objectively and efficiently than what is currently possible.

  7. Use of a novel cell adhesion method and digital measurement to show stimulus-dependent variation in somatic and oral ciliary beat frequency in Paramecium.

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    Bell, Wade E; Hallworth, Richard; Wyatt, Todd A; Sisson, Joseph H

    2015-01-01

    When Paramecium encounters positive stimuli, the membrane hyperpolarizes and ciliary beat frequency increases. We adapted an established immobilization protocol using a biological adhesive and a novel digital analysis system to quantify beat frequency in immobilized Paramecium. Cells showed low mortality and demonstrated beat frequencies consistent with previous studies. Chemoattractant molecules, reduction in external potassium, and posterior stimulation all increased somatic beat frequency. In all cases, the oral groove cilia maintained a higher beat frequency than mid-body cilia, but only oral cilia from cells stimulated with chemoattactants showed an increase from basal levels. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

  8. [Regeneration of the ciliary beat of human ciliated cells].

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    Wolf, G; Koidl, B; Pelzmann, B

    1991-10-01

    The influence of an isotonic, alkaline saline solution (diluted "Emser Sole" or brine from the spa of Bad Ems) on the ciliary beat of isolated cultured human ciliated cells of the upper respiratory tract was investigated. The ciliary beat was observed via an inverted phase contrast microscope (Zeiss Axiomat IDPC) and measured microphotometrically under physiological conditions and after the damaging influence of 1% propanal solution. Under physiological conditions the saline solution had a positive, although statistically not significant influence on the frequency of the ciliary beat. After damage of the cultivated cells by 1% propanal solution, the saline solution had a significant better influence on the regeneration of the cultured cells than a physiological sodium chloride solution. It is concluded that diluted brine from Bad Ems has a positive effect on the ciliary beat of the respiratory epithelium and accelerates its regeneration after damage by viral and bacterial infections, surgery or inhaled noxae.

  9. A Low-Cost Method of Ciliary Beat Frequency Measurement Using iPhone and MATLAB: Rabbit Study.

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    Chen, Jason J; Lemieux, Bryan T; Wong, Brian J F

    2016-08-01

    (1) To determine ciliary beat frequency (CBF) using a consumer-grade cellphone camera and MATLAB and (2) to evaluate the effectiveness and accuracy of the proposed method. Prospective animal study. Academic otolaryngology department research laboratory. Five ex vivo tracheal samples were extracted from 3 freshly euthanized (MATLAB programming, the video of the 23°C sample was downsampled to 120, 60, and 30 fps, and Fourier analysis was performed on videos of all frame rates and conditions to determine CBF. CBF of the 23°C sample was also calculated manually frame by frame for verification. Recorded at 240 fps, the CBF at 23°C was 5.03 ± 0.4 Hz, and the CBF at 37°C was 9.08 ± 0.49 Hz (P .05). There is no significant difference between CBF measured via visual inspection and that analyzed by the developed program. Furthermore, all tested acquisition rates are shown to be effective, providing a fast and inexpensive alternative to current CBF measurement protocols. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  10. Non‐diluted seawater enhances nasal ciliary beat frequency and wound repair speed compared to diluted seawater and normal saline

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    Bonnomet, Arnaud; Luczka, Emilie; Coraux, Christelle

    2016-01-01

    Background The regulation of mucociliary clearance is a key part of the defense mechanisms developed by the airway epithelium. If a high aggregate quality of evidence shows the clinical effectiveness of nasal irrigation, there is a lack of studies showing the intrinsic role of the different irrigation solutions allowing such results. This study investigated the impact of solutions with different pH and ionic compositions, eg, normal saline, non‐diluted seawater and diluted seawater, on nasal mucosa functional parameters. Methods For this randomized, controlled, blinded, in vitro study, we used airway epithelial cells obtained from 13 nasal polyps explants to measure ciliary beat frequency (CBF) and epithelial wound repair speed (WRS) in response to 3 isotonic nasal irrigation solutions: (1) normal saline 0.9%; (2) non‐diluted seawater (Physiomer®); and (3) 30% diluted seawater (Stérimar). The results were compared to control (cell culture medium). Results Non‐diluted seawater enhanced the CBF and the WRS when compared to diluted seawater and to normal saline. When compared to the control, it significantly enhanced CBF and slightly, though nonsignificantly, improved the WRS. Interestingly, normal saline markedly reduced the number of epithelial cells and ciliated cells when compared to the control condition. Conclusion Our results suggest that the physicochemical features of the nasal wash solution is important because it determines the optimal conditions to enhance CBF and epithelial WRS thus preserving the respiratory mucosa in pathological conditions. Non‐diluted seawater obtains the best results on CBF and WRS vs normal saline showing a deleterious effect on epithelial cell function. PMID:27101776

  11. Non-diluted seawater enhances nasal ciliary beat frequency and wound repair speed compared to diluted seawater and normal saline.

    Science.gov (United States)

    Bonnomet, Arnaud; Luczka, Emilie; Coraux, Christelle; de Gabory, Ludovic

    2016-10-01

    The regulation of mucociliary clearance is a key part of the defense mechanisms developed by the airway epithelium. If a high aggregate quality of evidence shows the clinical effectiveness of nasal irrigation, there is a lack of studies showing the intrinsic role of the different irrigation solutions allowing such results. This study investigated the impact of solutions with different pH and ionic compositions, eg, normal saline, non-diluted seawater and diluted seawater, on nasal mucosa functional parameters. For this randomized, controlled, blinded, in vitro study, we used airway epithelial cells obtained from 13 nasal polyps explants to measure ciliary beat frequency (CBF) and epithelial wound repair speed (WRS) in response to 3 isotonic nasal irrigation solutions: (1) normal saline 0.9%; (2) non-diluted seawater (Physiomer®); and (3) 30% diluted seawater (Stérimar). The results were compared to control (cell culture medium). Non-diluted seawater enhanced the CBF and the WRS when compared to diluted seawater and to normal saline. When compared to the control, it significantly enhanced CBF and slightly, though nonsignificantly, improved the WRS. Interestingly, normal saline markedly reduced the number of epithelial cells and ciliated cells when compared to the control condition. Our results suggest that the physicochemical features of the nasal wash solution is important because it determines the optimal conditions to enhance CBF and epithelial WRS thus preserving the respiratory mucosa in pathological conditions. Non-diluted seawater obtains the best results on CBF and WRS vs normal saline showing a deleterious effect on epithelial cell function. © 2016 The Authors International Forum of Allergy & Rhinology, published by ARSAAOA, LLC.

  12. Vicks VapoRub induces mucin secretion, decreases ciliary beat frequency, and increases tracheal mucus transport in the ferret trachea.

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    Abanses, Juan Carlos; Arima, Shinobu; Rubin, Bruce K

    2009-01-01

    Vicks VapoRub (VVR) [Proctor and Gamble; Cincinnati, OH] is often used to relieve symptoms of chest congestion. We cared for a toddler in whom severe respiratory distress developed after VVR was applied directly under her nose. We hypothesized that VVR induced inflammation and adversely affected mucociliary function, and tested this hypothesis in an animal model of airway inflammation. [1] Trachea specimens excised from 15 healthy ferrets were incubated in culture plates lined with 200 mg of VVR, and the mucin secretion was compared to those from controls without VVR. Tracheal mucociliary transport velocity (MCTV) was measured by timing the movement of 4 microL of mucus across the trachea. Ciliary beat frequency (CBF) was measured using video microscopy. [2] Anesthetized and intubated ferrets inhaled a placebo or VVR that was placed at the proximal end of the endotracheal tube. We evaluated both healthy ferrets and animals in which we first induced tracheal inflammation with bacterial endotoxin (a lipopolysaccharide [LPS]). Mucin secretion was measured using an enzyme-linked lectin assay, and lung water was measured by wet/dry weight ratios. [1] Mucin secretion was increased by 63% over the controls in the VVR in vitro group (p < 0.01). CBF was decreased by 35% (p < 0.05) in the VVR group. [2] Neither LPS nor VVR increased lung water, but LPS decreased MCTV in both normal airways (31%) and VVR-exposed airways (30%; p = 0.03), and VVR increased MCTV by 34% in LPS-inflamed airways (p = 0.002). VVR stimulates mucin secretion and MCTV in the LPS-inflamed ferret airway. This set of findings is similar to the acute inflammatory stimulation observed with exposure to irritants, and may lead to mucus obstruction of small airways and increased nasal resistance.

  13. Paramecium swimming and ciliary beating patterns: a study on four RNA interference mutations.

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    Funfak, Anette; Fisch, Cathy; Abdel Motaal, Hatem T; Diener, Julien; Combettes, Laurent; Baroud, Charles N; Dupuis-Williams, Pascale

    2015-01-01

    Paramecium cells swim and feed by beating their thousands of cilia in coordinated patterns. The organization of these patterns and its relationship with cell motility has been the subject of a large body of work, particularly as a model for ciliary beating in human organs where similar organization is seen. However the rapid motion of the cells makes quantitative measurements very challenging. Here we provide detailed measurements of the swimming of Paramecium cells from high-speed video at high magnification, as they move in microfluidic channels. An image analysis protocol allows us to decouple the cell movement from the motion of the cilia, thus allowing us to measure the ciliary beat frequency (CBF) and the spatio-temporal organization into metachronal waves along the cell periphery. Two distinct values of the CBF appear at different regions of the cell: most of the cilia beat in the range of 15 to 45 Hz, while the cilia in the peristomal region beat at almost double the frequency. The body and peristomal CBF display a nearly linear relation with the swimming velocity. Moreover the measurements do not display a measurable correlation between the swimming velocity and the metachronal wave velocity on the cell periphery. These measurements are repeated for four RNAi silenced mutants, where proteins specific to the cilia or to their connection to the cell base are depleted. We find that the mutants whose ciliary structure is affected display similar swimming to the control cells albeit with a reduced efficiency, while the mutations that affect the cilia's anchoring to the cell lead to strongly reduced ability to swim. This reduction in motility can be related to a loss of coordination between the ciliary beating in different parts of the cell.

  14. Particulate matter in cigarette smoke increases ciliary axoneme beating through mechanical stimulation.

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    Navarrette, Chelsea R; Sisson, Joseph H; Nance, Elizabeth; Allen-Gipson, Diane; Hanes, Justin; Wyatt, Todd A

    2012-06-01

    The lung's ability to trap and clear foreign particles via the mucociliary elevator is an important mechanism for protecting the lung against respirable irritants and microorganisms. Although cigarette smoke (CS) exposure and particulate inhalation are known to alter mucociliary clearance, little is known about how CS and nanoparticles (NPs) modify cilia beating at the cytoskeletal infrastructure, or axonemal, level. We used a cell-free model to introduce cigarette smoke extract (CSE) and NPs with variant size and surface chemistry to isolated axonemes and measured changes in ciliary motility. We hypothesized that CSE would alter cilia beating and that alterations in ciliary beat frequency (CBF) due to particulate matter would be size- and surface chemistry-dependent. Demembranated axonemes were isolated from ciliated bovine tracheas and exposed to adenosine triphosphate (ATP) to initiate motility. CBF was measured in response to 5% CSE, CSE filtrate, and carboxyl-modified (COOH), sulphate (SO(4))-modified (sulfonated), or PEG-coated polystyrene (PS) latex NPs ranging in size from 40 nm to 500 nm. CSE concentrations as low as 5% resulted in rapid, significant stimulation of CBF (pIntroduction of sulphate-modified PS beads ~300 nm in diameter resulted in a similar increase in CBF above baseline ATP levels. Uncharged, PEG-coated beads had no effect on CBF regardless of size. Similarly, COOH-coated particles less than 200 nm in diameter did not alter ciliary motility. However, COOH-coated PS particles larger than 300 nm increased CBF significantly and increased the number of motile points. These data show that NPs, including those found in CSE, mechanically stimulate axonemes in a size- and surface chemistry-dependent manner. Alterations in ciliary motility due to physicochemical properties of NPs may be important for inhalational lung injury and efficient drug delivery of respirable particles.

  15. Binaural beats at high frequencies.

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    McFadden, D; Pasanen, E G

    1975-10-24

    Binaural beats have long been believed to be audible only at low frequencies, but an interaction reminiscent of a binaural beat can sometimes be heard when different two-tone complexes of high frequency are presented to the two ears. The primary requirement is that the frequency separation in the complex at one ear be slightly different from that in the other--that is, that there be a small interaural difference in the envelope periodicities. This finding is in accord with other recent demonstrations that the auditory system is not deaf to interaural time differences at high frequencies.

  16. Effect of Cilia Beat Frequency on Mucociliary Clearance

    Directory of Open Access Journals (Sweden)

    Sedaghat M. H.

    2016-12-01

    Full Text Available Background: The airway surface liquid (ASL, which is a fluid layer coating the interior epithelial surface of the bronchi and bronchiolesis, plays an important defensive role against foreign particles and chemicals entering lungs. Objective: Numerical investigation has been employed to solve two-layer model consisting of mucus layer as a viscoelastic fluid and periciliary liquid layer as a Newtonian fluid to study the effects of cilia beat frequency (CBF at various amounts of mucus properties on muco-ciliary transport problem. Methods: Hybrid finite difference-lattice Boltzmann-method (FB-LBM has been used to solve the momentum equations and to simulate cilia forces, and also the PCLmucus interface more accurately, immersed boundary method (IBM has been employed. The main contribution of the current study is to use an Oldroyd-B model as the constitutive equation of mucus. Results: Our results show that increasing CBF and decreasing mucus viscosity ratio have great effects on mucus flow, but the effect of viscosity ratio is more significant. The results also illustrate that the relation between cilia beat frequency and mean mucus velocity is almost linear and it has similar behavior at different values of viscosity ratio. Conclusion: Numerical investigation based on hybrid IB-FD-LBM has been used to study the effect of CBF at various mounts of mucus viscosity ratio on the muco-ciliary clearance. The results showed that the effect of viscosity ratio on the muco-ciliary transport process is more significant compared with CBF.

  17. Binaural beats and frequency-coding.

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    Fritze, W; Köhler, W

    1986-01-01

    Binaural beats were studied before and during a situation of temporary threshold shift, and no frequency shift could be found. In contrast, subjective binaural frequency comparison revealed a distinct shift. These findings demonstrate the two known modes of perception.

  18. Control of ventricular ciliary beating by the Melanin Concentrating Hormone-expressing neurons of the lateral hypothalamus : a functional imaging survey.

    Directory of Open Access Journals (Sweden)

    Gregory eConductier

    2013-11-01

    Full Text Available The cyclic peptide Melanin-Concentrating Hormone (MCH is known to control a large number of brain functions in mammals such as food intake and metabolism, stress response, anxiety, sleep/wake cycle, memory and reward. Based on neuroanatomical and electrophysiological studies these functions were attributed to neuronal circuits expressing MCHR1, the single MCH receptor in rodents. In complement to our recently published work (Conductier et al. 2013 we provided here new data regarding the action of MCH on ependymocytes in the mouse brain. First, we establish that MCHR1 mRNA is expressed in the ependymal cells of the third ventricle epithelium. Second, we demonstated a tonic control of MCH-expressing neurons on ependymal cilia beat frequency using in vitro optogenics. Finally, we performed in vivo measurements of CSF flow using fluorescent micro-beads in wild-type and MCHR1 knockout mice. Collectively, our results demonstrated that MCH-expressing neurons modulate ciliary beating of ependymal cells at the third ventricle and could contribute to maintain cerebro-spinal fluid homeostasis.

  19. Beat frequency ultrasonic microsphere contrast agent detection system

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    Pretlow, III, Robert A. (Inventor); Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    1997-01-01

    A system for and method of detecting and measuring concentrations of an ultrasonically-reflective microsphere contrast agent involving detecting non-linear sum and difference beat frequencies produced by the microspheres when two impinging signals with non-identical frequencies are combined by mixing. These beat frequencies can be used for a variety of applications such as detecting the presence of and measuring the flow rates of biological fluids and industrial liquids, including determining the concentration level of microspheres in the myocardium.

  20. Nonlinear beat excitation of low frequency wave in degenerate plasmas

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    Mir, Zahid; Shahid, M.; Jamil, M.; Rasheed, A.; Shahbaz, A.

    2018-03-01

    The beat phenomenon due to the coupling of two signals at slightly different frequencies that generates the low frequency signal is studied. The linear dispersive properties of the pump and sideband are analyzed. The modified nonlinear dispersion relation through the field coupling of linear modes against the beat frequency is derived in the homogeneous quantum dusty magnetoplasmas. The dispersion relation is used to derive the modified growth rate of three wave parametric instability. Moreover, significant quantum effects of electrons through the exchange-correlation potential, the Bohm potential, and the Fermi pressure evolved in macroscopic three wave interaction are presented. The analytical results are interpreted graphically describing the significance of the work. The applications of this study are pointed out at the end of introduction.

  1. Effect of N-acetylcysteine on the human nasal ciliary activity in vitro

    DEFF Research Database (Denmark)

    Stafanger, G; Bisgaard, H; Pedersen, M

    1987-01-01

    N-acetylcysteine (NAC) is widely used as a mucolytic agent, but the clinical and pharmacological effects of NAC are still unclear. It has recently been claimed in animal studies that NAC will stimulate ciliary beating frequency at low concentrations, while inhibiting beating at higher concentrati......N-acetylcysteine (NAC) is widely used as a mucolytic agent, but the clinical and pharmacological effects of NAC are still unclear. It has recently been claimed in animal studies that NAC will stimulate ciliary beating frequency at low concentrations, while inhibiting beating at higher...... concentrations. Using a microphoto-oscillographic method combined with microperfusion technique, we studied the direct effect of NAC on human nasal cilia. NAC caused a direct dose- and time-related decrease in ciliary beating frequency, which was detectable at 2 mg/ml and reached statistically significant levels...

  2. MHD simulation of a beat frequency heated plasma

    International Nuclear Information System (INIS)

    Milroy, R.D.; Capjack, C.E.; James, C.R.; McMullin, J.N.

    1976-01-01

    The heating of a plasma in a solenoid, with a beat frequency harmonic which is excited at a frequency near to that of a Langmuir mode in a plasma, is examined. It is shown that at high temperatures the heating rate is very insensitive to changes in plasma density. The amount of energy that can be coupled to a plasma in a solenoid with this heating scheme is investigated by using a one-dimensional computer code which incorporates an exact solution of the relevant MHD equations. The absorption of energy from a high powered laser is shown to be significantly enhanced with this process. (author)

  3. The brain responses to different frequencies of binaural beat sounds on QEEG at cortical level.

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    Jirakittayakorn, Nantawachara; Wongsawat, Yodchanan

    2015-01-01

    Beat phenomenon is occurred when two slightly different frequency waves interfere each other. The beat can also occur in the brain by providing two slightly different frequency waves separately each ear. This is called binaural beat. The brain responses to binaural beat are in discussion process whether the brain side and the brain area. Therefore, this study aims to figure out the brain responses to binaural beat by providing different binaural beat frequencies on 250 carrier tone continuously for 30 minutes to participants and using quantitative electroencephalography (QEEG) to interpret the data. The result shows that different responses appear in different beat frequency. Left hemisphere dominance occur in 3 Hz beat within 15 minutes and 15 Hz beat within 5 minutes. Right hemisphere dominance occurs in 10 Hz beat within 25 minute. 6 Hz beat enhances all area of the brain within 10 minutes. 8 Hz and 25 Hz beats have no clearly responses while 40 Hz beat enhances the responses in frontal lobe. These brain responses can be used for brain modulation application to induce the brain activity in further studies.

  4. An autocrine ATP release mechanism regulates basal ciliary activity in airway epithelium.

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    Droguett, Karla; Rios, Mariana; Carreño, Daniela V; Navarrete, Camilo; Fuentes, Christian; Villalón, Manuel; Barrera, Nelson P

    2017-07-15

    Extracellular ATP, in association with [Ca 2+ ] i regulation, is required to maintain basal ciliary beat frequency. Increasing extracellular ATP levels increases ciliary beating in airway epithelial cells, maintaining a sustained response by inducing the release of additional ATP. Extracellular ATP levels in the millimolar range, previously associated with pathophysiological conditions of the airway epithelium, produce a transient arrest of ciliary activity. The regulation of ciliary beat frequency is dependent on ATP release by hemichannels (connexin/pannexin) and P2X receptor activation, the blockage of which may even stop ciliary movement. The force exerted by cilia, measured by atomic force microscopy, is reduced following extracellular ATP hydrolysis. This result complements the current understanding of the ciliary beating regulatory mechanism, with special relevance to inflammatory diseases of the airway epithelium that affect mucociliary clearance. Extracellular nucleotides, including ATP, are locally released by the airway epithelium and stimulate ciliary activity in a [Ca 2+ ] i -dependent manner after mechanical stimulation of ciliated cells. However, it is unclear whether the ATP released is involved in regulating basal ciliary activity and mediating changes in ciliary activity in response to chemical stimulation. In the present study, we evaluated ciliary beat frequency (CBF) and ciliary beating forces in primary cultures from mouse tracheal epithelium, using videomicroscopy and atomic force microscopy (AFM), respectively. Extracellular ATP levels and [Ca 2+ ] i were measured by luminometric and fluorimetric assays, respectively. Uptake of ethidium bromide was measured to evaluate hemichannel functionality. We show that hydrolysis of constitutive extracellular ATP levels with apyrase (50 U ml -1 ) reduced basal CBF by 45% and ciliary force by 67%. The apyrase effect on CBF was potentiated by carbenoxolone, a hemichannel inhibitor, and oxidized ATP, an

  5. Cyanide levels found in infected cystic fibrosis sputum inhibit airway ciliary function.

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    Nair, Chandrika; Shoemark, Amelia; Chan, Mario; Ollosson, Sarah; Dixon, Mellissa; Hogg, Claire; Alton, Eric W F W; Davies, Jane C; Williams, Huw D

    2014-11-01

    We have previously reported cyanide at concentrations of up to 150 μM in the sputum of cystic fibrosis patients infected with Pseudomonas aeruginosa and a negative correlation with lung function. Our aim was to investigate possible mechanisms for this association, focusing on the effect of pathophysiologically relevant cyanide levels on human respiratory cell function. Ciliary beat frequency measurements were performed on nasal brushings and nasal air-liquid interface (ALI) cultures obtained from healthy volunteers and cystic fibrosis patients. Potassium cyanide decreased ciliary beat frequency in healthy nasal brushings (n = 6) after 60 min (150 μM: 47% fall, pcyanide as a key component inhibiting the ciliary beat frequency. If cyanide production similarly impairs mucocilliary clearance in vivo, it could explain the link with increased disease severity observed in cystic fibrosis patients with detectable cyanide in their airway. ©ERS 2014.

  6. A new index for characterizing micro-bead motion in a flow induced by ciliary beating: Part II, modeling.

    Directory of Open Access Journals (Sweden)

    Mathieu Bottier

    2017-07-01

    Full Text Available Mucociliary clearance is one of the major lines of defense of the human respiratory system. The mucus layer coating the airways is constantly moved along and out of the lung by the activity of motile cilia, expelling at the same time particles trapped in it. The efficiency of the cilia motion can experimentally be assessed by measuring the velocity of micro-beads traveling through the fluid surrounding the cilia. Here we present a mathematical model of the fluid flow and of the micro-beads motion. The coordinated movement of the ciliated edge is represented as a continuous envelope imposing a periodic moving velocity boundary condition on the surrounding fluid. Vanishing velocity and vanishing shear stress boundary conditions are applied to the fluid at a finite distance above the ciliated edge. The flow field is expanded in powers of the amplitude of the individual cilium movement. It is found that the continuous component of the horizontal velocity at the ciliated edge generates a 2D fluid velocity field with a parabolic profile in the vertical direction, in agreement with the experimental measurements. Conversely, we show than this model can be used to extract microscopic properties of the cilia motion by extrapolating the micro-bead velocity measurement at the ciliated edge. Finally, we derive from these measurements a scalar index providing a direct assessment of the cilia beating efficiency. This index can easily be measured in patients without any modification of the current clinical procedures.

  7. Study on the Relationship among Parents' Cognition on China Anti-Domestic Violence, Attitude of Beating Children and Frequency of Beating Children

    Science.gov (United States)

    Song, Shi

    2018-01-01

    This research aims at analyzing the correlation between parents' awareness of anti-domestic violence in China, attitude and frequency of beating children. According to the literature analysis, this paper sets children's parents' anti-domestic violence cognition and attitude of beating children as independent variable, and the frequency of beating…

  8. The effect of beat frequency on eye movements during free viewing.

    Science.gov (United States)

    Maróti, Emese; Knakker, Balázs; Vidnyánszky, Zoltán; Weiss, Béla

    2017-02-01

    External periodic stimuli entrain brain oscillations and affect perception and attention. It has been shown that background music can change oculomotor behavior and facilitate detection of visual objects occurring on the musical beat. However, whether musical beats in different tempi modulate information sampling differently during natural viewing remains to be explored. Here we addressed this question by investigating how listening to naturalistic drum grooves in two different tempi affects eye movements of participants viewing natural scenes on a computer screen. We found that the beat frequency of the drum grooves modulated the rate of eye movements: fixation durations were increased at the lower beat frequency (1.7Hz) as compared to the higher beat frequency (2.4Hz) and no music conditions. Correspondingly, estimated visual sampling frequency decreased as fixation durations increased with lower beat frequency. These results imply that slow musical beats can retard sampling of visual information during natural viewing by increasing fixation durations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. High-frequency ultrasound measurements of the normal ciliary body and iris.

    Science.gov (United States)

    Garcia, Julian P S; Spielberg, Leigh; Finger, Paul T

    2011-01-01

    To determine the normal ultrasonographic thickness of the iris and ciliary body. This prospective 35-MHz ultrasonographic study included 80 normal eyes of 40 healthy volunteers. The images were obtained at the 12-, 3-, 6-, and 9-o'clock radial meridians, measured at three locations along the radial length of the iris and at the thickest section of the ciliary body. Mixed model was used to estimate eye site-adjusted means and standard errors and to test the statistical difference of adjusted results. Parameters included mean thickness, standard deviation, and range. Mean thicknesses at the iris root, midway along the radial length of the iris, and at the juxtapupillary margin were 0.4 ± 0.1, 0.5 ± 0.1, and 0.6 ± 0.1 mm, respectively. Those of the ciliary body, ciliary processes, and ciliary body + ciliary processes were 0.7 ± 0.1, 0.6 ± 0.1, and 1.3 ± 0.2 mm, respectively. This study provides standard, normative thickness data for the iris and ciliary body in healthy adults using ultrasonographic imaging. Copyright 2011, SLACK Incorporated.

  10. Culture of primary ciliary dyskinesia epithelial cells at air-liquid interface can alter ciliary phenotype but remains a robust and informative diagnostic aid.

    Directory of Open Access Journals (Sweden)

    Robert A Hirst

    Full Text Available The diagnosis of primary ciliary dyskinesia (PCD requires the analysis of ciliary function and ultrastructure. Diagnosis can be complicated by secondary effects on cilia such as damage during sampling, local inflammation or recent infection. To differentiate primary from secondary abnormalities, re-analysis of cilia following culture and re-differentiation of epithelial cells at an air-liquid interface (ALI aids the diagnosis of PCD. However changes in ciliary beat pattern of cilia following epithelial cell culture has previously been described, which has brought the robustness of this method into question. This is the first systematic study to evaluate ALI culture as an aid to diagnosis of PCD in the light of these concerns.We retrospectively studied changes associated with ALI-culture in 158 subjects referred for diagnostic testing at two PCD centres. Ciliated nasal epithelium (PCD n = 54; non-PCD n  111 was analysed by high-speed digital video microscopy and transmission electron microscopy before and after culture.Ciliary function was abnormal before and after culture in all subjects with PCD; 21 PCD subjects had a combination of static and uncoordinated twitching cilia, which became completely static following culture, a further 9 demonstrated a decreased ciliary beat frequency after culture. In subjects without PCD, secondary ciliary dyskinesia was reduced.The change to ciliary phenotype in PCD samples following cell culture does not affect the diagnosis, and in certain cases can assist the ability to identify PCD cilia.

  11. Electrophysiological measurement of binaural beats: effects of primary tone frequency and observer age.

    Science.gov (United States)

    Grose, John H; Mamo, Sara K

    2012-01-01

    The purpose of this study was to determine the reliability of the electrophysiological binaural beat steady state response as a gauge of temporal fine structure coding, particularly as it relates to the aging auditory system. The hypothesis was that the response would be more robust in a lower, than in a higher, frequency region and in younger, than in older, adults. Two experiments were undertaken. The first measured the 40 Hz binaural beat steady state response elicited by tone pairs in two frequency regions: lower (390 and 430 Hz tone pair) and higher (810 and 850 Hz tone pair). Frequency following responses (FFRs) evoked by the tones were also recorded. Ten young adults with normal hearing participated. The second experiment measured the binaural beat and FFRs in older adults but only in the lower frequency region. Fourteen older adults with relatively normal hearing participated. Response metrics in both experiments included response component signal-to-noise ratio (F statistic) and magnitude-squared coherence. Experiment 1 showed that FFRs were elicited in both frequency regions but were more robust in the lower frequency region. Binaural beat responses elicited by the lower frequency pair of tones showed greater amplitude fluctuation within a participant than the respective FFRs. Experiment 2 showed that older adults exhibited similar FFRs to younger adults, but proportionally fewer older participants showed binaural beat responses. Age differences in onset responses were also observed. The lower prevalence of the binaural beat response in older adults, despite the presence of FFRs, provides tentative support for the sensitivity of this measure to age-related deficits in temporal processing. However, the lability of the binaural beat response advocates caution in its use as an objective measure of fine structure coding.

  12. Utilization of negative beat-frequencies for maximizing the update-rate of OFDR

    Science.gov (United States)

    Gabai, Haniel; Botsev, Yakov; Hahami, Meir; Eyal, Avishay

    2015-07-01

    In traditional OFDR systems, the backscattered profile of a sensing fiber is inefficiently duplicated to the negative band of spectrum. In this work, we present a new OFDR design and algorithm that remove this redundancy and make use of negative beat frequencies. In contrary to conventional OFDR designs, it facilitates efficient use of the available system bandwidth and enables distributed sensing with the maximum allowable interrogation update-rate for a given fiber length. To enable the reconstruction of negative beat frequencies an I/Q type receiver is used. In this receiver, both the in-phase (I) and quadrature (Q) components of the backscatter field are detected. Following detection, both components are digitally combined to produce a complex backscatter signal. Accordingly, due to its asymmetric nature, the produced spectrum will not be corrupted by the appearance of negative beat-frequencies. Here, via a comprehensive computer simulation, we show that in contrast to conventional OFDR systems, I/Q OFDR can be operated at maximum interrogation update-rate for a given fiber length. In addition, we experimentally demonstrate, for the first time, the ability of I/Q OFDR to utilize negative beat-frequencies for long-range distributed sensing.

  13. High-Frequency Binaural Beats Increase Cognitive Flexibility: Evidence from Dual-Task Crosstalk.

    Science.gov (United States)

    Hommel, Bernhard; Sellaro, Roberta; Fischer, Rico; Borg, Saskia; Colzato, Lorenza S

    2016-01-01

    Increasing evidence suggests that cognitive-control processes can be configured to optimize either persistence of information processing (by amplifying competition between decision-making alternatives and top-down biasing of this competition) or flexibility (by dampening competition and biasing). We investigated whether high-frequency binaural beats, an auditory illusion suspected to act as a cognitive enhancer, have an impact on cognitive-control configuration. We hypothesized that binaural beats in the gamma range bias the cognitive-control style toward flexibility, which in turn should increase the crosstalk between tasks in a dual-task paradigm. We replicated earlier findings that the reaction time in the first-performed task is sensitive to the compatibility between the responses in the first and the second task-an indication of crosstalk. As predicted, exposing participants to binaural beats in the gamma range increased this effect as compared to a control condition in which participants were exposed to a continuous tone of 340 Hz. These findings provide converging evidence that the cognitive-control style can be systematically biased by inducing particular internal states; that high-frequency binaural beats bias the control style toward more flexibility; and that different styles are implemented by changing the strength of local competition and top-down bias.

  14. High-frequency binaural beats increase cognitive flexibility: evidence from dual-task crosstalk

    Directory of Open Access Journals (Sweden)

    Bernhard Hommel

    2016-08-01

    Full Text Available Increasing evidence suggests that cognitive-control processes can be configured to optimize either persistence of information processing (by amplifying competition between decision-making alternatives and top-down biasing of this competition or flexibility (by dampening competition and biasing. We investigated whether high-frequency binaural beats, an auditory illusion suspected to act as a cognitive enhancer, have an impact on cognitive-control configuration. We hypothesized that binaural beats in the gamma range bias the cognitive-control style towards flexibility, which in turn should increase the crosstalk between tasks in a dual-task paradigm. We replicated earlier findings that the reaction time in the first-performed task is sensitive to the compatibility between the responses in the first and the second task—an indication of crosstalk. As predicted, exposing participants to binaural beats in the gamma range increased this effect as compared to a control condition in which participants were exposed to a continuous tone of 340 Hz. These findings provide converging evidence that the cognitive-control style can be systematically biased by inducing particular internal states; that high-frequency binaural beats bias the control style towards more flexibility; and that different styles are implemented by changing the strength of local competition and top-down bias.

  15. Enhanced speed in fluorescence imaging using beat frequency multiplexing

    Science.gov (United States)

    Mikami, Hideharu; Kobayashi, Hirofumi; Wang, Yisen; Hamad, Syed; Ozeki, Yasuyuki; Goda, Keisuke

    2016-03-01

    Fluorescence imaging using radiofrequency-tagged emission (FIRE) is an emerging technique that enables higher imaging speed (namely, temporal resolution) in fluorescence microscopy compared to conventional fluorescence imaging techniques such as confocal microscopy and wide-field microscopy. It works based on the principle that it uses multiple intensity-modulated fields in an interferometric setup as excitation fields and applies frequency-division multiplexing to fluorescence signals. Unfortunately, despite its high potential, FIRE has limited imaging speed due to two practical limitations: signal bandwidth and signal detection efficiency. The signal bandwidth is limited by that of an acousto-optic deflector (AOD) employed in the setup, which is typically 100-200 MHz for the spectral range of fluorescence excitation (400-600 nm). The signal detection efficiency is limited by poor spatial mode-matching between two interfering fields to produce a modulated excitation field. Here we present a method to overcome these limitations and thus to achieve higher imaging speed than the prior version of FIRE. Our method achieves an increase in signal bandwidth by a factor of two and nearly optimal mode matching, which enables the imaging speed limited by the lifetime of the target fluorophore rather than the imaging system itself. The higher bandwidth and better signal detection efficiency work synergistically because higher bandwidth requires higher signal levels to avoid the contribution of shot noise and amplifier noise to the fluorescence signal. Due to its unprecedentedly high-speed performance, our method has a wide variety of applications in cancer detection, drug discovery, and regenerative medicine.

  16. Pectoral fin beat frequency predicts oxygen consumption during spontaneous activity in a labriform swimming fish (Embiotoca lateralis)

    DEFF Research Database (Denmark)

    Tudorache, Christian; Jordan, Anders D.; Svendsen, Jon Christian

    2009-01-01

    The objective of this study was to identify kinematic variables correlated with oxygen consumption during spontaneous labriform swimming. Kinematic variables (swimming speed, change of speed, turning angle, turning rate, turning radius and pectoral fin beat frequency) and oxygen consumption (MO2......) of spontaneous swimming in Embiotoca lateralis were measured in a circular arena using video tracking and respirometry, respectively. The main variable influencing MO2 was pectoral fin beat frequency (r (2) = 0.71). No significant relationship was found between swimming speed and pectoral fin beat frequency....... Complementary to other methods within biotelemetry such as EMG it is suggested that such correlations of pectoral fin beat frequency may be used to measure the energy requirements of labriform swimming fish such as E. lateralis in the field, but need to be taken with great caution since movement and oxygen...

  17. Measurement of optical-beat frequency in a photoconductive terahertz-wave generator using microwave higher harmonics.

    Science.gov (United States)

    Murasawa, Kengo; Sato, Koki; Hidaka, Takehiko

    2011-05-01

    A new method for measuring optical-beat frequencies in the terahertz (THz) region using microwave higher harmonics is presented. A microwave signal was applied to the antenna gap of a photoconductive (PC) device emitting a continuous electromagnetic wave at about 1 THz by the photomixing technique. The microwave higher harmonics with THz frequencies are generated in the PC device owing to the nonlinearity of the biased photoconductance, which is briefly described in this article. Thirteen nearly periodic peaks in the photocurrent were observed when the microwave was swept from 16 to 20 GHz at a power of -48 dBm. The nearly periodic peaks are generated by the homodyne detection of the optical beat with the microwave higher harmonics when the frequency of the harmonics coincides with the optical-beat frequency. Each peak frequency and its peak width were determined by fitting a Gaussian function, and the order of microwave harmonics was determined using a coarse (i.e., lower resolution) measurement of the optical-beat frequency. By applying the Kalman algorithm to the peak frequencies of the higher harmonics and their standard deviations, the optical-beat frequency near 1 THz was estimated to be 1029.81 GHz with the standard deviation of 0.82 GHz. The proposed method is applicable to a conventional THz-wave generator with a photomixer.

  18. Periodic rotation noise induced by the crosstalk between two beat-frequency signals in multi-oscillator ring laser gyros

    International Nuclear Information System (INIS)

    Lu, Guangfeng; Wang, Zhiguo; Fan, Zhenfang; Luo, Hui

    2014-01-01

    Periodic rotation noise in the outputs of multi-oscillator ring laser gyros (MRLGs) is investigated in this paper for the first time. It is proved theoretically and experimentally that noise is induced by the crosstalk between two beat-frequency signals, which are combined from the left and right circularly polarized counter-propagating beams in MRLGs. Theoretical analysis and experimental results also indicate that the fundamental frequency of this noise is equal to the frequency difference between the two beat-frequency signals and the amplitude of the fundamental component is proportional to the crosstalk ratio between the two beat-frequency signals. Further, the amplitude of the nth-order component is proportional to the nth power of the crosstalk ratio. (paper)

  19. Fast phase stabilization of a low frequency beat note for atom interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Oh, E.; Horne, R. A.; Sackett, C. A., E-mail: sackett@virginia.edu [Department of Physics, University of Virginia, 382 McCormick Road, Charlottesville, Virginia 22904-4714 (United States)

    2016-06-15

    Atom interferometry experiments rely on the ability to obtain a stable signal that corresponds to an atomic phase. For interferometers that use laser beams to manipulate the atoms, noise in the lasers can lead to errors in the atomic measurement. In particular, it is often necessary to actively stabilize the optical phase between two frequency components of the beams. Typically this is achieved using a time-domain measurement of a beat note between the two frequencies. This becomes challenging when the frequency difference is small and the phase measurement must be made quickly. The method presented here instead uses a spatial interference detection to rapidly measure the optical phase for arbitrary frequency differences. A feedback system operating at a bandwidth of about 10 MHz could then correct the phase in about 3 μs. This time is short enough that the phase correction could be applied at the start of a laser pulse without appreciably degrading the fidelity of the atom interferometer operation. The phase stabilization system was demonstrated in a simple atom interferometer measurement of the {sup 87}Rb recoil frequency.

  20. Odors pulsed at wing beat frequencies are tracked by primary olfactory networks and enhance odor detection

    Directory of Open Access Journals (Sweden)

    Shreejoy Tripathy

    2010-03-01

    Full Text Available Each down stroke of an insect’s wings accelerates axial airflow over the antennae. Modeling studies suggest that this can greatly enhance penetration of air and air-born odorants through the antennal sensilla thereby periodically increasing odorant-receptor interactions. Do these periodic changes result in entrainment of neural responses in the antenna and antennal lobe (AL? Does this entrainment affect olfactory acuity? To address these questions, we monitored antennal and AL responses in the moth Manduca sexta while odorants were pulsed at frequencies from 10-72 Hz, encompassing the natural wingbeat frequency. Power spectral density (PSD analysis was used to identify entrainment of neural activity. Statistical analysis of PSDs indicates that the antennal nerve tracked pulsed odor up to 30 Hz. Furthermore, at least 50% of AL local field potentials (LFPs and between 7-25% of unitary spiking responses also tracked pulsed odor up to 30 Hz in a frequency-locked manner. Application of bicuculline (200µM abolished pulse tracking in both LFP and unitary responses suggesting that GABAA receptor activation is necessary for pulse tracking within the AL. Finally, psychophysical measures of odor detection establish that detection thresholds are lowered when odor is pulsed at 20 Hz. These results suggest that AL networks can respond to the oscillatory dynamics of stimuli such as those imposed by the wing beat in a manner analogous to mammalian sniffing.

  1. Alteration of frequency range for binaural beats in acute low-tone hearing loss.

    Science.gov (United States)

    Karino, Shotaro; Yamasoba, Tatsuya; Ito, Ken; Kaga, Kimitaka

    2005-01-01

    The effect of acute low-tone sensorineural hearing loss (ALHL) on the interaural frequency difference (IFD) required for perception of binaural beats (BBs) was investigated in 12 patients with unilateral ALHL and 7 patients in whom ALHL had lessened. A continuous pure tone of 30 dB sensation level at 250 Hz was presented to the contralateral, normal-hearing ear. The presence of BBs was determined by a subjective yes-no procedure as the frequency of a loudness-balanced test tone was gradually adjusted around 250 Hz in the affected ear. The frequency range in which no BBs were perceived (FRNB) was significantly wider in the patients with ALHL than in the controls, and FRNBs became narrower in the recovered ALHL group. Specifically, detection of slow BBs with a small IFD was impaired in this limited (10 s) observation period. The significant correlation between the hearing level at 250 Hz and FRNBs suggests that FRNBs represent the degree of cochlear damage caused by ALHL.

  2. Analysis of EEG activity in response to binaural beats with different frequencies.

    Science.gov (United States)

    Gao, Xiang; Cao, Hongbao; Ming, Dong; Qi, Hongzhi; Wang, Xuemin; Wang, Xiaolu; Chen, Runge; Zhou, Peng

    2014-12-01

    When two coherent sounds with nearly similar frequencies are presented to each ear respectively with stereo headphones, the brain integrates the two signals and produces a sensation of a third sound called binaural beat (BB). Although earlier studies showed that BB could influence behavior and cognition, common agreement on the mechanism of BB has not been reached yet. In this work, we employed Relative Power (RP), Phase Locking Value (PLV) and Cross-Mutual Information (CMI) to track EEG changes during BB stimulations. EEG signals were acquired from 13 healthy subjects. Five-minute BBs with four different frequencies were tested: delta band (1 Hz), theta band (5 Hz), alpha band (10 Hz) and beta band (20 Hz). We observed RP increase in theta and alpha bands and decrease in beta band during delta and alpha BB stimulations. RP decreased in beta band during theta BB, while RP decreased in theta band during beta BB. However, no clear brainwave entrainment effect was identified. Connectivity changes were detected following the variation of RP during BB stimulations. Our observation supports the hypothesis that BBs could affect functional brain connectivity, suggesting that the mechanism of BB-brain interaction is worth further study. Copyright © 2014. Published by Elsevier B.V.

  3. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

    OpenAIRE

    Patrick eMcConnell; Patrick eMcConnell; Brett eFroeliger; Eric L. Garland; Jeffrey C. Ives; Gary A. Sforzo

    2014-01-01

    Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics (heart-rate variability (HRV)) during post-exercise relaxation...

  4. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

    OpenAIRE

    McConnell, Patrick A.; Froeliger, Brett; Garland, Eric L.; Ives, Jeffrey C.; Sforzo, Gary A.

    2014-01-01

    Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics [heart rate variability (HRV)] during post-exercise relaxation...

  5. Digital frequency offset-locked He–Ne laser system with high beat frequency stability, narrow optical linewidth and optical fibre output

    Science.gov (United States)

    Sternkopf, Christian; Manske, Eberhard

    2018-06-01

    We report on the enhancement of a previously-presented heterodyne laser source on the basis of two phase-locked loop (PLL) frequency coupled internal-mirror He–Ne lasers. Our new system consists of two digitally controlled He–Ne lasers with slightly different wavelengths, and offers high-frequency stability and very narrow optical linewidth. The digitally controlled system has been realized by using a FPGA controller and transconductance amplifiers. The light of both lasers was coupled into separate fibres for heterodyne interferometer applications. To enhance the laser performance we observed the sensitivity of both laser tubes to electromagnetic noise from various laser power supplies and frequency control systems. Furthermore, we describe how the linewidth of a frequency-controlled He–Ne laser can be reduced during precise frequency stabilisation. The digitally controlled laser source reaches a standard beat frequency deviation of less than 20 Hz (with 1 s gate time) and a spectral full width at half maximum (FWHM) of the beat signal less than 3 kHz. The laser source has enough optical output power to serve a fibre-coupled multi axis heterodyne interferometer. The system can be adjusted to output beat frequencies in the range of 0.1 MHz–20 MHz.

  6. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal.

    Science.gov (United States)

    McConnell, Patrick A; Froeliger, Brett; Garland, Eric L; Ives, Jeffrey C; Sforzo, Gary A

    2014-01-01

    Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation), few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics [heart rate variability (HRV)] during post-exercise relaxation. Subjects (n = 21; 18-29 years old) participated in a double-blind, placebo-controlled study during which binaural beats and placebo were administered over two randomized and counterbalanced sessions (within-subjects repeated-measures design). At the onset of each visit, subjects exercised for 20-min; post-exercise, subjects listened to either binaural beats ('wide-band' theta-frequency binaural beats) or placebo (carrier tones) for 20-min while relaxing alone in a quiet, low-light environment. Dependent variables consisted of high-frequency (HF, reflecting parasympathetic activity), low-frequency (LF, reflecting sympathetic and parasympathetic activity), and LF/HF normalized powers, as well as self-reported relaxation. As compared to the placebo visit, the binaural-beat visit resulted in greater self-reported relaxation, increased parasympathetic activation and increased sympathetic withdrawal. By the end of the 20-min relaxation period there were no observable differences in HRV between binaural-beat and placebo visits, although binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.

  7. Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal

    Directory of Open Access Journals (Sweden)

    Patrick eMcConnell

    2014-11-01

    Full Text Available Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. Although this phenomenon is thought to facilitate state changes (e.g., relaxation, few empirical studies have reported on whether binaural beats produce changes in autonomic arousal. Therefore, the present study investigated the effects of binaural beating on autonomic dynamics (heart-rate variability (HRV during post-exercise relaxation. Subjects (n = 21; 18-29 years old participated in a double-blind, placebo-controlled study during which binaural beats and placebo were administered over two randomized and counterbalanced sessions (within-subjects repeated-measures design. At the onset of each visit, subjects exercised for 20-min; post-exercise, subjects listened to either binaural beats (‘wide-band’ theta-frequency binaural beats or placebo (carrier tone for 20-min while relaxing alone in a quiet, low-light environment. Dependent variables consisted of high frequency (HF, reflecting parasympathetic activity, low frequency (LF, reflecting sympathetic and parasympathetic activity and LF/HF normalized powers, as well as self-reported relaxation. As compared to the placebo visit, the binaural beat visit resulted in greater self-reported relaxation, as well as increased parasympathetic activation and sympathetic withdrawal. By the end of the 20-min relaxation period there were no observable differences in HRV between binaural beat and placebo visits, although binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.

  8. Three types of ependymal cells with intracellular calcium oscillation are characterized by distinct cilia beating properties.

    Science.gov (United States)

    Liu, Tongyu; Jin, Xingjian; Prasad, Rahul M; Sari, Youssef; Nauli, Surya M

    2014-09-01

    Ependymal cells are multiciliated epithelial cells that line the ventricles in the adult brain. Abnormal function or structure of ependymal cilia has been associated with various neurological deficits. For the first time, we report three distinct ependymal cell types, I, II, and III, based on their unique ciliary beating frequency and beating angle. These ependymal cells have specific localizations within the third ventricle of the mouse brain. Furthermore, neither ependymal cell types nor their localizations are altered by aging. Our high-speed fluorescence imaging analysis reveals that these ependymal cells have an intracellular pacing calcium oscillation property. Our study further shows that alcohol can significantly repress the amplitude of calcium oscillation and the frequency of ciliary beating, resulting in an overall decrease in volume replacement by the cilia. Furthermore, the pharmacological agent cilostazol could differentially increase cilia beating frequency in type II, but not in type I or type III, ependymal cells. In summary, we provide the first evidence of three distinct types of ependymal cells with calcium oscillation properties. © 2014 Wiley Periodicals, Inc.

  9. Fish and robots swimming together in a water tunnel: robot color and tail-beat frequency influence fish behavior.

    Directory of Open Access Journals (Sweden)

    Giovanni Polverino

    Full Text Available The possibility of integrating bioinspired robots in groups of live social animals may constitute a valuable tool to study the basis of social behavior and uncover the fundamental determinants of animal functions and dysfunctions. In this study, we investigate the interactions between individual golden shiners (Notemigonus crysoleucas and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish positional preference with respect to the robot is experimentally analyzed as the robot's color pattern and tail-beat frequency are varied. Behavioral observations are corroborated by particle image velocimetry studies aimed at investigating the flow structure behind the robotic fish. Experimental results show that the time spent by golden shiners in the vicinity of the bioinspired robotic fish is the highest when the robot mimics their natural color pattern and beats its tail at the same frequency. In these conditions, fish tend to swim at the same depth of the robotic fish, where the wake from the robotic fish is stronger and hydrodynamic return is most likely to be effective.

  10. Fish and robots swimming together in a water tunnel: robot color and tail-beat frequency influence fish behavior.

    Science.gov (United States)

    Polverino, Giovanni; Phamduy, Paul; Porfiri, Maurizio

    2013-01-01

    The possibility of integrating bioinspired robots in groups of live social animals may constitute a valuable tool to study the basis of social behavior and uncover the fundamental determinants of animal functions and dysfunctions. In this study, we investigate the interactions between individual golden shiners (Notemigonus crysoleucas) and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish positional preference with respect to the robot is experimentally analyzed as the robot's color pattern and tail-beat frequency are varied. Behavioral observations are corroborated by particle image velocimetry studies aimed at investigating the flow structure behind the robotic fish. Experimental results show that the time spent by golden shiners in the vicinity of the bioinspired robotic fish is the highest when the robot mimics their natural color pattern and beats its tail at the same frequency. In these conditions, fish tend to swim at the same depth of the robotic fish, where the wake from the robotic fish is stronger and hydrodynamic return is most likely to be effective.

  11. Partition of aerobic and anaerobic swimming costs and their correlation to tail-beat frequency and burst activity in Sparus aurata

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2012-01-01

    until fatigue at 10°C. The anaerobic swimming cost was measured as the excess postexercise oxygen consumption (EPOC) following each swimming speed. To determine tail-beat frequency, amplitude and burst and coast behaviour, the peduncle position was determined at 25 s·' by video tracking. The data showed......, and resulted in a total anaerobic capacity of 170 mg O2 kg·'. Normalized tail-beat amplitude and frequency both predicted the swimming speed but only tail-beat frequency was able to predict the aerobic swimming cost. The change to burst and coast swimming was correlated to the first measurements of EPOC...... and both the burst frequency (bursts min·') and burst distance (percentage burst distance) were found to predict EPOC by linear regressions. The low temperature used in the present study resulted in a prolonged recovery time, which increased with the anaerobic contribution to 10 hours after fatigue. Due...

  12. Energy savings in sea bass swimming in a school: measurements of tail beat frequency and oxygen consumption at different swimming speeds

    DEFF Research Database (Denmark)

    Herskin, J; Steffensen, JF

    1998-01-01

    Tail beat frequency of sea bass, Dicentrarchus labrax (L.) (23.5 ± 0·5 cm, LT), swimming at the front of a school was significantly higher than when swimming at the rear, for all water velocities tested from 14·8 to 32 cm s-1. The logarithm of oxygen consumption rate, and the tail beat frequency...... of solitary swimming sea bass (28·8 ± 0·4 cm, LT), were each correlated linearly with swimming speed, and also with one another. The tail beat frequency of individual fish was 9-14% lower when at the rear of a school than when at the front, corresponding to a 9-23% reduction in oxygen consumption rate....

  13. Pseudotumor of Ciliary Body

    Directory of Open Access Journals (Sweden)

    Mary Varghese

    2014-01-01

    Full Text Available Orbital pseudotumor is a benign disease involving the orbital structures. Pseudotumor of the ciliary body is rare. We present a case of a 27-year-old male who presented with gradual visual loss, pain, and redness in his left eye. On examination he was found to have a yellowish white mass at the periphery of anterior chamber in his left eye and ultrasound biomicroscopy (UBM revealed a ciliary body mass in the same eye. He was treated with systemic steroids, which was tapered over a period of 8 weeks. His symptoms improved and the ciliary body mass disappeared with no recurrence over the next 6 months. UBM is an important diagnostic tool for diagnosing ciliary body mass. Early diagnosis and prompt treatment with systemic steroids may help resolve pseudotumor of the ciliary body.

  14. [Research of dual-photoelastic-modulator-based beat frequency modulation and Fourier-Bessel transform imaging spectrometer].

    Science.gov (United States)

    Wang, Zhi-Bin; Zhang, Rui; Wang, Yao-Li; Huang, Yan-Fei; Chen, You-Hua; Wang, Li-Fu; Yang, Qiang

    2014-02-01

    As the existing photoelastic-modulator(PEM) modulating frequency in the tens of kHz to hundreds of kHz between, leading to frequency of modulated interference signal is higher, so ordinary array detector cannot effectively caprure interference signal..A new beat frequency modulation method based on dual-photoelastic-modulator (Dual-PEM) and Fourier-Bessel transform is proposed as an key component of dual-photoelastic-modulator-based imaging spectrometer (Dual-PEM-IS) combined with charge coupled device (CCD). The dual-PEM are operated as an electro-optic circular retardance modulator, Operating the PEMs at slightly different resonant frequencies w1 and w2 respectively, generates a differential signal at a much lower heterodyne frequency that modulates the incident light. This method not only retains the advantages of the existing PEM, but also the frequency of modulated photocurrent decreased by 2-3 orders of magnitude (10-500 Hz) and can be detected by common array detector, and the incident light spectra can be obtained by Fourier-Bessel transform of low frequency component in the modulated signal. The method makes the PEM has the dual capability of imaging and spectral measurement. The basic principle is introduced, the basic equations is derived, and the feasibility is verified through the corresponding numerical simulation and experiment. This method has' potential applications in imaging spectrometer technology, and analysis of the effect of deviation of the optical path difference. This work provides the necessary theoretical basis for remote sensing of new Dual-PEM-IS and for engineering implementation of spectra inversion.

  15. Functional short- and long-term effects of nasal CPAP with and without humidification on the ciliary function of the nasal respiratory epithelium.

    Science.gov (United States)

    Sommer, J Ulrich; Kraus, Marius; Birk, Richard; Schultz, Johannes D; Hörmann, Karl; Stuck, Boris A

    2014-03-01

    Continuous positive airway pressure (CPAP) is the gold standard in the treatment of obstructive sleep apnea (OSA), but its impact on ciliary function is unclear to date. Furthermore, CPAP is associated with numerous side effects related to the nose and upper airway. Humidified CPAP is used to relieve these symptoms, but again, little is known regarding its effect on ciliary function of the nasal respiratory epithelium. In this prospective, randomized, crossover trial, 31 patients with OSA (AHI >15/h) were randomized to two treatment arms: nasal continuous positive airway pressure (nCPAP) with humidification or nCPAP without humidification for one night in each modality to assess short-term effects of ciliary beat frequency (CBF) and mucus transport time (MTT) and consecutively for 8 weeks in each modality to assess long-term effects in a crossover fashion. The baseline CBF was 4.8 ± 0.6 Hz, and baseline MTT was 540 ± 221 s. After one night of CPAP with and without humidification, ciliary function increased moderately yet with statistical significance (p humidification did not differ statistically significant. Regarding long-term effects of CPAP, a statistically significant increase in ciliary function above the baseline level and above the short-term level was shown without humidification (7.2 ± 0.4 Hz; 402 ± 176 s; p humidification (9.3 ± 0.7 Hz; 313 ± 95 s; p humidification, nCPAP has moderate effects on short-term ciliary function of the nasal respiratory epithelium. However, a significant increase in ciliary function-both in terms of an increased CBF and a decreased MTT-was detected after long-term use. The effect was more pronounced when humidification was used during nCPAP.

  16. On binaural beats.

    Science.gov (United States)

    Fritze, W

    1985-01-01

    Binaural beats have been investigated in normal volunteers using high-stable synthesizers. There are considerable differences between the subjective rhythm heard and the difference of the two frequencies, indicating that this dissimilarity must be caused centrally.

  17. LRRC6 mutation causes primary ciliary dyskinesia with dynein arm defects.

    Directory of Open Access Journals (Sweden)

    Amjad Horani

    Full Text Available Despite recent progress in defining the ciliome, the genetic basis for many cases of primary ciliary dyskinesia (PCD remains elusive. We evaluated five children from two unrelated, consanguineous Palestinian families who had PCD with typical clinical features, reduced nasal nitric oxide concentrations, and absent dynein arms. Linkage analyses revealed a single common homozygous region on chromosome 8 and one candidate was conserved in organisms with motile cilia. Sequencing revealed a single novel mutation in LRRC6 (Leucine-rich repeat containing protein 6 that fit the model of autosomal recessive genetic transmission, leading to a change of a highly conserved amino acid from aspartic acid to histidine (Asp146His. LRRC6 was localized to the cytoplasm and was up-regulated during ciliogenesis in human airway epithelial cells in a Foxj1-dependent fashion. Nasal epithelial cells isolated from affected individuals and shRNA-mediated silencing in human airway epithelial cells, showed reduced LRRC6 expression, absent dynein arms, and slowed cilia beat frequency. Dynein arm proteins were either absent or mislocalized to the cytoplasm in airway epithelial cells from a primary ciliary dyskinesia subject. These findings suggest that LRRC6 plays a role in dynein arm assembly or trafficking and when mutated leads to primary ciliary dyskinesia with laterality defects.

  18. Effects of three-mode field interactions in laser instabilities and in beat-frequency spectroscopy

    International Nuclear Information System (INIS)

    Herdow, S.T.

    1982-01-01

    Population pulsations are fluctuations in the population difference (of a two level system) due to the presence of two or more coherent waves interfering in the medium. In this work, the author shows that population pulsations generated by three waves, a central wave and two mode-locked sidebands, are responsible for both the multiwavelength and the single-wavelength instabilities of single-mode lasers containing homgeneously-broadened media. The role of the population pulsations in establishing these instabilities, however, diminish as the central mode is detuned away from the atomic resonance frequency. For homogeneously-broadened lasers, the author finds two regions of single-wavelength instability. The first is at line center, for which population pulsations are solely responsible, and the second is off line center where the unsaturated medium provides the required gain and anomalous dispersion. For the case of inhomogeneously-broadened lasers, the author shows that population pulsations significantly increase the instability range over that predicted by Casperson for single-mode bad-cavity lasers. Both the unidirectional ring and the standing-wave cavities are treated. The Fourier expansion technique, used in this work, for treating three-frequency operation in saturation spectroscopy is shown to be equivalent (in appropriate limits) to the linear stability analysis in laser theory and optical bistability. The author also shows, in single-sideband saturation spectroscopy, that for long interaction lengths propagation effects can significantly influence the absorption and dispersion coefficients of the medium. Finally, the author shows that under certain conditions the pronounced splitting effects of the population pulsations develop into regions of intense absorption

  19. Kinematic and EMG data during underwater dolphin kick change while synchronizing with or without synchronization of kick frequency with the beat of a metronome.

    Science.gov (United States)

    Yamakawa, Keisuke Kobayashi; Shimojo, Hirofumi; Takagi, Hideki; Tsubakimoto, Shozo; Sengoku, Yasuo

    2017-10-01

    We investigated the effects of synchronizing kick frequency with the beat of a metronome on kinematic and electromyographic (EMG) parameters during the underwater dolphin kick as a pilot study related to the research that entitled " Effect of increased kick frequency on propelling efficiency and muscular co-activation during underwater dolphin kick" (Yamakawa et al., 2017) [1]. Seven collegiate female swimmers participated in this experiment. The participants conducted two underwater dolphin kick trials: swimming freely at maximum effort, and swimming while synchronizing the kick frequency of maximum effort with the beat of a metronome. The kinematic parameters during the underwater dolphin kick were calculated by 2-D motion analysis, and surface electromyographic measurements were taken from six muscles (rectus abdominis, erector spinae, rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius). The results revealed no significant differences in the kinematic and EMG parameters between trials of the two swimming techniques. Therefore, the action of synchronizing the kick frequency with the beat of a metronome did not affect movement or muscle activity during the underwater dolphin kick in this experiment.

  20. Kinematic and EMG data during underwater dolphin kick change while synchronizing with or without synchronization of kick frequency with the beat of a metronome

    Directory of Open Access Journals (Sweden)

    Keisuke Kobayashi Yamakawa

    2017-10-01

    Full Text Available We investigated the effects of synchronizing kick frequency with the beat of a metronome on kinematic and electromyographic (EMG parameters during the underwater dolphin kick as a pilot study related to the research that entitled “Effect of increased kick frequency on propelling efficiency and muscular co-activation during underwater dolphin kick” (Yamakawa et al., 2017 [1]. Seven collegiate female swimmers participated in this experiment. The participants conducted two underwater dolphin kick trials: swimming freely at maximum effort, and swimming while synchronizing the kick frequency of maximum effort with the beat of a metronome. The kinematic parameters during the underwater dolphin kick were calculated by 2-D motion analysis, and surface electromyographic measurements were taken from six muscles (rectus abdominis, erector spinae, rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius. The results revealed no significant differences in the kinematic and EMG parameters between trials of the two swimming techniques. Therefore, the action of synchronizing the kick frequency with the beat of a metronome did not affect movement or muscle activity during the underwater dolphin kick in this experiment.

  1. A comparison of auditory evoked potentials to acoustic beats and to binaural beats.

    Science.gov (United States)

    Pratt, Hillel; Starr, Arnold; Michalewski, Henry J; Dimitrijevic, Andrew; Bleich, Naomi; Mittelman, Nomi

    2010-04-01

    The purpose of this study was to compare cortical brain responses evoked by amplitude modulated acoustic beats of 3 and 6 Hz in tones of 250 and 1000 Hz with those evoked by their binaural beats counterparts in unmodulated tones to indicate whether the cortical processes involved differ. Event-related potentials (ERPs) were recorded to 3- and 6-Hz acoustic and binaural beats in 2000 ms duration 250 and 1000 Hz tones presented with approximately 1 s intervals. Latency, amplitude and source current density estimates of ERP components to beats-evoked oscillations were determined and compared across beat types, beat frequencies and base (carrier) frequencies. All stimuli evoked tone-onset components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude in response to acoustic than to binaural beats, to 250 than to 1000 Hz base frequency and to 3 Hz than to 6 Hz beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left temporal lobe areas. Differences between estimated sources of potentials to acoustic and binaural beats were not significant. The perceptions of binaural beats involve cortical activity that is not different than acoustic beats in distribution and in the effects of beat- and base frequency, indicating similar cortical processing. Copyright 2010 Elsevier B.V. All rights reserved.

  2. Using music structure to improve beat tracking

    Science.gov (United States)

    Dannenberg, Roger B.

    2005-09-01

    Beats are an important feature of most music. Beats are used in music information retrieval systems for genre classification, similarity search, and segmentation. However, beats can be difficult to identify, especially in music audio. Traditional beat trackers attempt to (1) match predicted beats to observations of likely beats, and (2) maintain a fairly steady tempo. A third criterion can be added: when repetitions of musical passages occur, the beats in the first repetition should align with the beats in all other repetitions. This third criterion improves beat tracking performance significantly. Repetitions of musical passages are discovered in audio data by searching for similar sequences of chroma vectors. Beats are ``tracked'' by first locating a sequence of likely beats in the music audio using high frequency energy as an indicator of beat likelihood. This beat sequence is then extended by searching forward and backward for more matching beats, allowing slight variations in tempo, and using a relaxation algorithm to optimize the proposed beat locations with respect to the three criteria. Other high-level music features may offer further improvements in beat identification.

  3. Lung transfer factor and KCO at cardiac frequency 100 beats/min as a guide to impaired function of lung parenchyma.

    OpenAIRE

    Chu, S S; Cotes, J E

    1984-01-01

    Transfer factor (TL) and KCO have been measured by the single breath carbon monoxide method in 39 patients with confirmed or suspected lung disease, mostly of occupational origin, and 37 healthy subjects. TL and KCO at an exercise cardiac frequency of 100 beats/min (TL100 and KCO100) and the slopes of the regression of exercise transfer factor and KCO on exercise cardiac frequency (delta TL/delta fC and delta KCO/delta fC) were obtained. The discriminatory performance of these indices in dete...

  4. Ciliary dysfunction and obesity.

    Science.gov (United States)

    Mok, C A; Héon, E; Zhen, M

    2010-01-01

    Obesity associates with increased health risks such as heart disease, stroke and diabetes. The steady rise in the obese population worldwide poses an increasing burden on health systems. Genetic factors contribute to the development of obesity, and the elucidation of their physiological functions helps to understand the cause, and improve the prevention, diagnosis and treatment for this disorder. Primary cilia are evolutionarily conserved organelles whose dysfunctions lead to human disorders now defined as ciliopathies. Human ciliopathies present pleiotropic and overlapping phenotypes that often include retinal degeneration, cystic renal anomalies and obesity. Increasing evidence implicates an intriguing involvement of cilia in lipid/energy homeostasis. Here we discuss recent studies in support of the key roles of ciliary genes in the development and pathology of obesity in various animal models. Genes affecting ciliary development and function may pose promising candidate underlying genetic factors that contribute to the development of common obesity.

  5. Beat Dreams?

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2009-01-01

    Two of the founding members of the Beat Generation of the 1950s wrote dream books with almost identical titles: Jack Kerouac's Book of Dreams (1961) and William Burroughs' My Education: A Book of Dreams (1995). This paper queries the function of such dream books, both from a perspective of seeing...... dream writing as a confessional genre, and from the perspective of didacticism implicit in sharing one's dream life with one's readers. What role does memory, politics, fantasies and reality play in communicating with and via dreams?...

  6. Synergism between sulfur dioxide and carbon particles. Studies on adsorption and on ciliary movements in the rabbit trachea in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Dalhamn, T; Strandberg, L

    1963-01-01

    Various types of carbon were shown to absorb gaseous SO/sub 2/ (about 75% at equilibrium in one case), which was rapidly converted to sulfuric acid (30% of that adsorbed in one case). However, carbon did not act synergistically with SO/sub 2/ in reducing rabbit trachea ciliary beat; carbon had no effect by itself and had no additional effect when administered with SO/sub 2/. 74 to 134 ppM SO/sub 2/ reduced ciliary beat from 1265 to 1091 beats/min after 45 min, and 175 to 239 ppM SO/sub 2/ reduced it from 1200 to 891 beats/min after 45 min.

  7. The beat is getting stronger : The effect of atmospheric stability on low frequency modulated sound of wind turbines

    NARCIS (Netherlands)

    van den Berg, G P

    2005-01-01

    Sound from wind turbines involves a number of sound production mechanisms related to different interactions between the turbine blades and the air. An important contribution to the low frequency part of the sound spectrum is due to the sudden variation in air flow which the blade encounters when it

  8. Impact of physiological variables and genetic background on myocardial frequency-resistivity relations in the intact beating murine heart.

    Science.gov (United States)

    Reyes, Maricela; Steinhelper, Mark E; Alvarez, Jorge A; Escobedo, Daniel; Pearce, John; Valvano, Jonathan W; Pollock, Brad H; Wei, Chia-Ling; Kottam, Anil; Altman, David; Bailey, Steven; Thomsen, Sharon; Lee, Shuko; Colston, James T; Oh, Jung Hwan; Freeman, Gregory L; Feldman, Marc D

    2006-10-01

    Conductance measurements for generation of an instantaneous left ventricular (LV) volume signal in the mouse are limited, because the volume signal is a combination of blood and LV muscle, and only the blood signal is desired. We have developed a conductance system that operates at two simultaneous frequencies to identify and remove the myocardial contribution to the instantaneous volume signal. This system is based on the observation that myocardial resistivity varies with frequency, whereas blood resistivity does not. For calculation of LV blood volume with the dual-frequency conductance system in mice, in vivo murine myocardial resistivity was measured and combined with an analytic approach. The goals of the present study were to identify and minimize the sources of error in the measurement of myocardial resistivity to enhance the accuracy of the dual-frequency conductance system. We extended these findings to a gene-altered mouse model to determine the impact of measured myocardial resistivity on the calculation of LV pressure-volume relations. We examined the impact of temperature, timing of the measurement during the cardiac cycle, breeding strain, anisotropy, and intrameasurement and interanimal variability on the measurement of intact murine myocardial resistivity. Applying this knowledge to diabetic and nondiabetic 11- and 20- to 24-wk-old mice, we demonstrated differences in myocardial resistivity at low frequencies, enhancement of LV systolic function at 11 wk and LV dilation at 20-24 wk, and histological and electron-microscopic studies demonstrating greater glycogen deposition in the diabetic mice. This study demonstrated the accurate technique of measuring myocardial resistivity and its impact on the determination of LV pressure-volume relations in gene-altered mice.

  9. Genetics Home Reference: primary ciliary dyskinesia

    Science.gov (United States)

    ... primary ciliary dyskinesia also have year-round nasal congestion and a chronic cough. Chronic respiratory tract infections ... likely due to abnormal cilia in the fallopian tubes. Another feature of primary ciliary dyskinesia is recurrent ...

  10. CCDC151 Mutations Cause Primary Ciliary Dyskinesia by Disruption of the Outer Dynein Arm Docking Complex Formation

    NARCIS (Netherlands)

    Hjeij, R.; Onoufriadis, A.; Watson, C.M.; Slagle, C.E.; Klena, N.T.; Dougherty, G.W.; Kurkowiak, M.; Loges, N.T.; Diggle, C.P.; Morante, N.F.; Gabriel, G.C.; Lemke, K.L.; Li, Y.; Pennekamp, P.; Menchen, T.; Konert, F.; Marthin, J.K.; Mans, D.A.; Letteboer, S.J.F.; Werner, C.; Burgoyne, T.; Westermann, C.; Rutman, A.; Carr, I.M.; O'Callaghan, C.; Moya, E.; Chung, E.M.; Consortium, U.K.; Sheridan, E.; Nielsen, K.G.; Roepman, R.; Bartscherer, K.; Burdine, R.D.; Lo, C.W.; Omran, H.; Mitchison, H.M.

    2014-01-01

    A diverse family of cytoskeletal dynein motors powers various cellular transport systems, including axonemal dyneins generating the force for ciliary and flagellar beating essential to movement of extracellular fluids and of cells through fluid. Multisubunit outer dynein arm (ODA) motor complexes,

  11. Losing the beat: deficits in temporal coordination

    Science.gov (United States)

    Palmer, Caroline; Lidji, Pascale; Peretz, Isabelle

    2014-01-01

    Tapping or clapping to an auditory beat, an easy task for most individuals, reveals precise temporal synchronization with auditory patterns such as music, even in the presence of temporal fluctuations. Most models of beat-tracking rely on the theoretical concept of pulse: a perceived regular beat generated by an internal oscillation that forms the foundation of entrainment abilities. Although tapping to the beat is a natural sensorimotor activity for most individuals, not everyone can track an auditory beat. Recently, the case of Mathieu was documented (Phillips-Silver et al. 2011 Neuropsychologia 49, 961–969. (doi:10.1016/j.neuropsychologia.2011.02.002)). Mathieu presented himself as having difficulty following a beat and exhibited synchronization failures. We examined beat-tracking in normal control participants, Mathieu, and a second beat-deaf individual, who tapped with an auditory metronome in which unpredictable perturbations were introduced to disrupt entrainment. Both beat-deaf cases exhibited failures in error correction in response to the perturbation task while exhibiting normal spontaneous motor tempi (in the absence of an auditory stimulus), supporting a deficit specific to perception–action coupling. A damped harmonic oscillator model was applied to the temporal adaptation responses; the model's parameters of relaxation time and endogenous frequency accounted for differences between the beat-deaf cases as well as the control group individuals. PMID:25385783

  12. Mucous flow and ciliary activity in the trachea of rats exposed to pulmonary irritant gas

    Energy Technology Data Exchange (ETDEWEB)

    Dalhamm, T; Rhodin, J

    1956-01-01

    Tracheal mucous secretion was increased in rats exposed to 10 ppM SO/sub 2/, 6 hr/day for 10 weeks. Mucous transport was decreased from 13.5 to 5 mm/min although ciliary beat remained a constant 1320 beats/min. The mucous layer was 5 times as thick as the normal ..mu..m. Histologically, cilia were generally unaffected whereas tracheal epithelium was irregular with deep crypts, and the lamina propria showed severe edema, fragmentation of collagen fibrils, and profuse vascularization with blood escaping perivascularly.

  13. Cortical evoked potentials to an auditory illusion: binaural beats.

    Science.gov (United States)

    Pratt, Hillel; Starr, Arnold; Michalewski, Henry J; Dimitrijevic, Andrew; Bleich, Naomi; Mittelman, Nomi

    2009-08-01

    To define brain activity corresponding to an auditory illusion of 3 and 6Hz binaural beats in 250Hz or 1000Hz base frequencies, and compare it to the sound onset response. Event-Related Potentials (ERPs) were recorded in response to unmodulated tones of 250 or 1000Hz to one ear and 3 or 6Hz higher to the other, creating an illusion of amplitude modulations (beats) of 3Hz and 6Hz, in base frequencies of 250Hz and 1000Hz. Tones were 2000ms in duration and presented with approximately 1s intervals. Latency, amplitude and source current density estimates of ERP components to tone onset and subsequent beats-evoked oscillations were determined and compared across beat frequencies with both base frequencies. All stimuli evoked tone-onset P(50), N(100) and P(200) components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude with the low base frequency and to the low beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left lateral and inferior temporal lobe areas in all stimulus conditions. Onset-evoked components were not different across stimulus conditions; P(50) had significantly different sources than the beats-evoked oscillations; and N(100) and P(200) sources located to the same temporal lobe regions as beats-evoked oscillations, but were bilateral and also included frontal and parietal contributions. Neural activity with slightly different volley frequencies from left and right ear converges and interacts in the central auditory brainstem pathways to generate beats of neural activity to modulate activities in the left temporal lobe, giving rise to the illusion of binaural beats. Cortical potentials recorded to binaural beats are distinct from onset responses. Brain activity corresponding to an auditory illusion of low frequency beats can be recorded from the scalp.

  14. Beat-to-Beat Blood Pressure Monitor

    Science.gov (United States)

    Lee, Yong Jin

    2012-01-01

    This device provides non-invasive beat-to-beat blood pressure measurements and can be worn over the upper arm for prolonged durations. Phase and waveform analyses are performed on filtered proximal and distal photoplethysmographic (PPG) waveforms obtained from the brachial artery. The phase analysis is used primarily for the computation of the mean arterial pressure, while the waveform analysis is used primarily to obtain the pulse pressure. Real-time compliance estimate is used to refine both the mean arterial and pulse pressures to provide the beat-to-beat blood pressure measurement. This wearable physiological monitor can be used to continuously observe the beat-to-beat blood pressure (B3P). It can be used to monitor the effect of prolonged exposures to reduced gravitational environments and the effectiveness of various countermeasures. A number of researchers have used pulse wave velocity (PWV) of blood in the arteries to infer the beat-to-beat blood pressure. There has been documentation of relative success, but a device that is able to provide the required accuracy and repeatability has not yet been developed. It has been demonstrated that an accurate and repeatable blood pressure measurement can be obtained by measuring the phase change (e.g., phase velocity), amplitude change, and distortion of the PPG waveforms along the brachial artery. The approach is based on comparing the full PPG waveform between two points along the artery rather than measuring the time-of-flight. Minimizing the measurement separation and confining the measurement area to a single, well-defined artery allows the waveform to retain the general shape between the two measurement points. This allows signal processing of waveforms to determine the phase and amplitude changes.

  15. Association between frequency of atrial and ventricular ectopic beats and biventricular pacing percentage and outcomes in patients with cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Ruwald, Martin H; Mittal, Suneet; Ruwald, Anne-Christine

    2014-01-01

    -defibrillator device with data available on biventricular pacing percentage and pre-implantation 24-h Holter recordings were included. Using logistic regression, we estimated the influence of ectopic beats on the percentage of biventricular pacing. Reverse remodeling was measured as reductions in atrial and left...

  16. Binaural auditory beats affect vigilance performance and mood.

    Science.gov (United States)

    Lane, J D; Kasian, S J; Owens, J E; Marsh, G R

    1998-01-01

    When two tones of slightly different frequency are presented separately to the left and right ears the listener perceives a single tone that varies in amplitude at a frequency equal to the frequency difference between the two tones, a perceptual phenomenon known as the binaural auditory beat. Anecdotal reports suggest that binaural auditory beats within the electroencephalograph frequency range can entrain EEG activity and may affect states of consciousness, although few scientific studies have been published. This study compared the effects of binaural auditory beats in the EEG beta and EEG theta/delta frequency ranges on mood and on performance of a vigilance task to investigate their effects on subjective and objective measures of arousal. Participants (n = 29) performed a 30-min visual vigilance task on three different days while listening to pink noise containing simple tones or binaural beats either in the beta range (16 and 24 Hz) or the theta/delta range (1.5 and 4 Hz). However, participants were kept blind to the presence of binaural beats to control expectation effects. Presentation of beta-frequency binaural beats yielded more correct target detections and fewer false alarms than presentation of theta/delta frequency binaural beats. In addition, the beta-frequency beats were associated with less negative mood. Results suggest that the presentation of binaural auditory beats can affect psychomotor performance and mood. This technology may have applications for the control of attention and arousal and the enhancement of human performance.

  17. Mutations in ZMYND10, a gene essential for proper axonemal assembly of inner and outer dynein arms in humans and flies, cause primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Moore, Daniel J; Onoufriadis, Alexandros; Shoemark, Amelia

    2013-01-01

    Primary ciliary dyskinesia (PCD) is a ciliopathy characterized by airway disease, infertility, and laterality defects, often caused by dual loss of the inner dynein arms (IDAs) and outer dynein arms (ODAs), which power cilia and flagella beating. Using whole-exome and candidate-gene Sanger resequ...

  18. The Impact of Monaural Beat Stimulation on Anxiety and Cognition

    Directory of Open Access Journals (Sweden)

    Leila Chaieb

    2017-05-01

    Full Text Available Application of auditory beat stimulation has been speculated to provide a promising new tool with which to alleviate symptoms of anxiety and to enhance cognition. In spite of reportedly similar EEG effects of binaural and monaural beats, data on behavioral effects of monaural beats are still lacking. Therefore, we examined the impact of monaural beat stimulation on anxiety, mood and memory performance. We aimed to target states related to anxiety levels and general well-being, in addition to long-term and working memory processes, using monaural beats within the range of main cortical rhythms. Theta (6 Hz, alpha (10 Hz and gamma (40 Hz beat frequencies, as well as a control stimulus were applied to healthy participants for 5 min. After each stimulation period, participants were asked to evaluate their current mood state and to perform cognitive tasks examining long-term and working memory processes, in addition to a vigilance task. Monaural beat stimulation was found to reduce state anxiety. When evaluating responses for the individual beat frequencies, positive effects on state anxiety were observed for all monaural beat conditions compared to control stimulation. Our results indicate a role for monaural beat stimulation in modulating state anxiety and are in line with previous studies reporting anxiety-reducing effects of auditory beat stimulation.

  19. The Impact of Monaural Beat Stimulation on Anxiety and Cognition.

    Science.gov (United States)

    Chaieb, Leila; Wilpert, Elke C; Hoppe, Christian; Axmacher, Nikolai; Fell, Juergen

    2017-01-01

    Application of auditory beat stimulation has been speculated to provide a promising new tool with which to alleviate symptoms of anxiety and to enhance cognition. In spite of reportedly similar EEG effects of binaural and monaural beats, data on behavioral effects of monaural beats are still lacking. Therefore, we examined the impact of monaural beat stimulation on anxiety, mood and memory performance. We aimed to target states related to anxiety levels and general well-being, in addition to long-term and working memory processes, using monaural beats within the range of main cortical rhythms. Theta (6 Hz), alpha (10 Hz) and gamma (40 Hz) beat frequencies, as well as a control stimulus were applied to healthy participants for 5 min. After each stimulation period, participants were asked to evaluate their current mood state and to perform cognitive tasks examining long-term and working memory processes, in addition to a vigilance task. Monaural beat stimulation was found to reduce state anxiety. When evaluating responses for the individual beat frequencies, positive effects on state anxiety were observed for all monaural beat conditions compared to control stimulation. Our results indicate a role for monaural beat stimulation in modulating state anxiety and are in line with previous studies reporting anxiety-reducing effects of auditory beat stimulation.

  20. Beat-wave generation of plasmons in semiconductor plasmas

    International Nuclear Information System (INIS)

    Berezhiani, V.I.; Mahajan, S.M.

    1995-08-01

    It is shown that in semiconductor plasmas, it is possible to generate large amplitude plasma waves by the beating of two laser beams with frequency difference close to the plasma frequency. For narrow gap seimconductors (for example n-type InSb), the system can simulate the physics underlying beat wave generation in relativistic gaseous plasmas

  1. Beat-wave generation of plasmons in semiconductor plasmas

    International Nuclear Information System (INIS)

    Berezhiani, V.I.; Mahajan, S.M.

    1995-08-01

    It is shown that in semiconductor plasmas, it is possible to generate large amplitude plasma waves by the beating of two laser beams with frequency difference close to the plasma frequency. For narrow gap semiconductor (for example n-type InSb), the system can simulate the physics underlying beat wave generation in relativistic gaseous plasmas. (author). 7 refs

  2. A binaural beat constructed from a noise

    Science.gov (United States)

    Akeroyd, Michael A

    2012-01-01

    The binaural beat has been used for over one hundred years as a stimulus for generating the percept of motion. Classically the beat consists of a pure tone at one ear (e.g. 500 Hz) and the same pure tone at the other ear but shifted upwards or downwards in frequency (e.g., 501 Hz). An experiment and binaural computational analysis are reported which demonstrate that a more powerful motion percept can be obtained by applying the concept of the frequency shift to a noise, via an upwards or downwards shift in the frequency of the Fourier components of its spectrum. PMID:21218863

  3. Binaural beat salience

    Science.gov (United States)

    Grose, John H.; Buss, Emily; Hall, Joseph W.

    2012-01-01

    Previous studies of binaural beats have noted individual variability and response lability, but little attention has been paid to the salience of the binaural beat percept. The purpose of this study was to gauge the strength of the binaural beat percept by matching its salience to that of sinusoidal amplitude modulation (SAM), and to then compare rate discrimination for the two types of fluctuation. Rate discrimination was measured for standard rates of 4, 8, 16, and 32 Hz – all in the 500-Hz carrier region. Twelve normal-hearing adults participated in this study. The results indicated that discrimination acuity for binaural beats is similar to that for SAM tones whose depths of modulation have been adjusted to provide equivalent modulation salience. The matched-salience SAM tones had relatively shallow depths of modulation, suggesting that the perceptual strength of binaural beats is relatively weak, although all listeners perceived them. The Weber fraction for detection of an increase in binaural beat rate is roughly constant across beat rates, at least for rates above 4 Hz, as is rate discrimination for SAM tones. PMID:22326292

  4. Binaural beat salience.

    Science.gov (United States)

    Grose, John H; Buss, Emily; Hall, Joseph W

    2012-03-01

    Previous studies of binaural beats have noted individual variability and response lability, but little attention has been paid to the salience of the binaural beat percept. The purpose of this study was to gauge the strength of the binaural beat percept by matching its salience to that of sinusoidal amplitude modulation (SAM), and to then compare rate discrimination for the two types of fluctuation. Rate discrimination was measured for standard rates of 4, 8, 16, and 32 Hz - all in the 500-Hz carrier region. Twelve normal-hearing adults participated in this study. The results indicated that discrimination acuity for binaural beats is similar to that for SAM tones whose depths of modulation have been adjusted to provide equivalent modulation salience. The matched-salience SAM tones had relatively shallow depths of modulation, suggesting that the perceptual strength of binaural beats is relatively weak, although all listeners perceived them. The Weber fraction for detection of an increase in binaural beat rate is roughly constant across beat rates, at least for rates above 4 Hz, as is rate discrimination for SAM tones. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Nonlinear amplitude dynamics in flagellar beating.

    Science.gov (United States)

    Oriola, David; Gadêlha, Hermes; Casademunt, Jaume

    2017-03-01

    The physical basis of flagellar and ciliary beating is a major problem in biology which is still far from completely understood. The fundamental cytoskeleton structure of cilia and flagella is the axoneme, a cylindrical array of microtubule doublets connected by passive cross-linkers and dynein motor proteins. The complex interplay of these elements leads to the generation of self-organized bending waves. Although many mathematical models have been proposed to understand this process, few attempts have been made to assess the role of dyneins on the nonlinear nature of the axoneme. Here, we investigate the nonlinear dynamics of flagella by considering an axonemal sliding control mechanism for dynein activity. This approach unveils the nonlinear selection of the oscillation amplitudes, which are typically either missed or prescribed in mathematical models. The explicit set of nonlinear equations are derived and solved numerically. Our analysis reveals the spatio-temporal dynamics of dynein populations and flagellum shape for different regimes of motor activity, medium viscosity and flagellum elasticity. Unstable modes saturate via the coupling of dynein kinetics and flagellum shape without the need of invoking a nonlinear axonemal response. Hence, our work reveals a novel mechanism for the saturation of unstable modes in axonemal beating.

  6. The impact of binaural beats on creativity

    Directory of Open Access Journals (Sweden)

    Susan A. Reedijk

    2013-11-01

    Full Text Available Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through stimulating neuronal phase locking. We aimed to investigate whether binaural beats affect creative performance at all, whether they affect divergent thinking, convergent thinking, or both, and whether possible effects may be mediated by the individual striatal dopamine level. Binaural beats were presented at alpha and gamma frequency. Participants completed a divergent and a convergent thinking task to assess two important functions of creativity, and filled out the Positive And Negative Affect Scale – mood State questionnaire (PANAS-S and affect grid to measure current mood. Dopamine levels in the striatum were estimated using spontaneous eye blink rates (EBRs. Results showed that binaural beats, regardless of the presented frequency, can affect divergent but not convergent thinking. Individuals with low EBRs mostly benefitted from alpha binaural beat stimulation, while individuals with high EBR were unaffected or even impaired by both alpha and gamma binaural beats. This suggests that binaural beats, and possibly other forms of cognitive entrainment, are not suited for a one-size-fits-all approach, and that individual cognitive-control systems need to be taken into account when studying cognitive enhancement methods.

  7. The impact of binaural beats on creativity.

    Science.gov (United States)

    Reedijk, Susan A; Bolders, Anne; Hommel, Bernhard

    2013-01-01

    Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through stimulating neuronal phase locking. We aimed to investigate whether binaural beats affect creative performance at all, whether they affect divergent thinking, convergent thinking, or both, and whether possible effects may be mediated by the individual striatal dopamine level. Binaural beats were presented at alpha and gamma frequency. Participants completed a divergent and a convergent thinking task to assess two important functions of creativity, and filled out the Positive And Negative Affect Scale-mood State questionnaire (PANAS-S) and an affect grid to measure current mood. Dopamine levels in the striatum were estimated using spontaneous eye blink rates (EBRs). Results showed that binaural beats, regardless of the presented frequency, can affect divergent but not convergent thinking. Individuals with low EBRs mostly benefitted from alpha binaural beat stimulation, while individuals with high EBRs were unaffected or even impaired by both alpha and gamma binaural beats. This suggests that binaural beats, and possibly other forms of cognitive entrainment, are not suited for a one-size-fits-all approach, and that individual cognitive-control systems need to be taken into account when studying cognitive enhancement methods.

  8. Binaural Beat: A Failure to Enhance EEG Power and Emotional Arousal

    Directory of Open Access Journals (Sweden)

    Fran López-Caballero

    2017-11-01

    Full Text Available When two pure tones of slightly different frequencies are delivered simultaneously to the two ears, is generated a beat whose frequency corresponds to the frequency difference between them. That beat is known as acoustic beat. If these two tones are presented one to each ear, they still produce the sensation of the same beat, although no physical combination of the tones occurs outside the auditory system. This phenomenon is called binaural beat. In the present study, we explored the potential contribution of binaural beats to the enhancement of specific electroencephalographic (EEG bands, as previous studies suggest the potential usefulness of binaural beats as a brainwave entrainment tool. Additionally, we analyzed the effects of binaural-beat stimulation on two psychophysiological measures related to emotional arousal: heart rate and skin conductance. Beats of five different frequencies (4.53 Hz -theta-, 8.97 Hz -alpha-, 17.93 Hz -beta-, 34.49 Hz -gamma- or 57.3 Hz -upper-gamma were presented binaurally and acoustically for epochs of 3 min (Beat epochs, preceded and followed by pink noise epochs of 90 s (Baseline and Post epochs, respectively. In each of these epochs, we analyzed the EEG spectral power, as well as calculated the heart rate and skin conductance response (SCR. For all the beat frequencies used for stimulation, no significant changes between Baseline and Beat epochs were observed within the corresponding EEG bands, neither with binaural or with acoustic beats. Additional analysis of spectral EEG topographies yielded negative results for the effect of binaural beats in the scalp distribution of EEG spectral power. In the psychophysiological measures, no changes in heart rate and skin conductance were observed for any of the beat frequencies presented. Our results do not support binaural-beat stimulation as a potential tool for the enhancement of EEG oscillatory activity, nor to induce changes in emotional arousal.

  9. Binaural Beat: A Failure to Enhance EEG Power and Emotional Arousal.

    Science.gov (United States)

    López-Caballero, Fran; Escera, Carles

    2017-01-01

    When two pure tones of slightly different frequencies are delivered simultaneously to the two ears, is generated a beat whose frequency corresponds to the frequency difference between them. That beat is known as acoustic beat. If these two tones are presented one to each ear, they still produce the sensation of the same beat, although no physical combination of the tones occurs outside the auditory system. This phenomenon is called binaural beat. In the present study, we explored the potential contribution of binaural beats to the enhancement of specific electroencephalographic (EEG) bands, as previous studies suggest the potential usefulness of binaural beats as a brainwave entrainment tool. Additionally, we analyzed the effects of binaural-beat stimulation on two psychophysiological measures related to emotional arousal: heart rate and skin conductance. Beats of five different frequencies (4.53 Hz -theta-, 8.97 Hz -alpha-, 17.93 Hz -beta-, 34.49 Hz -gamma- or 57.3 Hz -upper-gamma) were presented binaurally and acoustically for epochs of 3 min (Beat epochs), preceded and followed by pink noise epochs of 90 s (Baseline and Post epochs, respectively). In each of these epochs, we analyzed the EEG spectral power, as well as calculated the heart rate and skin conductance response (SCR). For all the beat frequencies used for stimulation, no significant changes between Baseline and Beat epochs were observed within the corresponding EEG bands, neither with binaural or with acoustic beats. Additional analysis of spectral EEG topographies yielded negative results for the effect of binaural beats in the scalp distribution of EEG spectral power. In the psychophysiological measures, no changes in heart rate and skin conductance were observed for any of the beat frequencies presented. Our results do not support binaural-beat stimulation as a potential tool for the enhancement of EEG oscillatory activity, nor to induce changes in emotional arousal.

  10. Analyzing the Acoustic Beat with Mobile Devices

    Science.gov (United States)

    Kuhn, Jochen; Vogt, Patrik; Hirth, Michael

    2014-01-01

    In this column, we have previously presented various examples of how physical relationships can be examined by analyzing acoustic signals using smartphones or tablet PCs. In this example, we will be exploring the acoustic phenomenon of small beats, which is produced by the overlapping of two tones with a low difference in frequency ?f. The…

  11. Wearable Beat to Beat Blood Pressure Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — A key component of NASA's human exploration programs is a system that monitors the health of the crew during space missions. The wearable beat-to-beat blood pressure...

  12. Primary ciliary dyskinesia: clinical and genetic aspects

    Directory of Open Access Journals (Sweden)

    E. D’Auria

    2012-06-01

    Full Text Available Primary ciliary dyskinesia (PCD is a rare, genetically heterogeneous disease, characterized by ciliary disfunction and impaired mucociliary clearance, resulting in a range of clinical manifestations such as chronic bronchitis, bronchiectasis, chronic rhino-sinusitis, chronic otitis media, situs viscerum inversus in almost 40-50% of cases and male infertility. The triad situs viscerum inversus, bronchiectasis and sinusitis is known as Kartagener syndrome. Up to now little is known about genetic, diagnostic and therapeutic aspects of primary motile ciliary diseases in children: for this reason, diagnosis is generally delayed and almost all treatments for PCD are not based on randomized studies but extrapolated from cystic fibrosis guidelines. The aim of this review is to propose to pediatricians a summary of current clinical and diagnostic evidence to obtain better knoledwge of this condition. The earlier diagnosis and the right treatment are both crucial to improve the prognosis of PCD.

  13. Binaural auditory beats affect long-term memory.

    Science.gov (United States)

    Garcia-Argibay, Miguel; Santed, Miguel A; Reales, José M

    2017-12-08

    The presentation of two pure tones to each ear separately with a slight difference in their frequency results in the perception of a single tone that fluctuates in amplitude at a frequency that equals the difference of interaural frequencies. This perceptual phenomenon is known as binaural auditory beats, and it is thought to entrain electrocortical activity and enhance cognition functions such as attention and memory. The aim of this study was to determine the effect of binaural auditory beats on long-term memory. Participants (n = 32) were kept blind to the goal of the study and performed both the free recall and recognition tasks after being exposed to binaural auditory beats, either in the beta (20 Hz) or theta (5 Hz) frequency bands and white noise as a control condition. Exposure to beta-frequency binaural beats yielded a greater proportion of correctly recalled words and a higher sensitivity index d' in recognition tasks, while theta-frequency binaural-beat presentation lessened the number of correctly remembered words and the sensitivity index. On the other hand, we could not find differences in the conditional probability for recall given recognition between beta and theta frequencies and white noise, suggesting that the observed changes in recognition were due to the recollection component. These findings indicate that the presentation of binaural auditory beats can affect long-term memory both positively and negatively, depending on the frequency used.

  14. Measuring and characterizing beat phenomena with a smartphone

    Science.gov (United States)

    Osorio, M.; Pereyra, C. J.; Gau, D. L.; Laguarda, A.

    2018-03-01

    Nowadays, smartphones are in everyone’s life. Apart from being excellent tools for work and communication, they can also be used to perform several measurements of simple physical magnitudes, serving as a mobile and inexpensive laboratory, ideal for use physics lectures in high schools or universities. In this article, we use a smartphone to analyse the acoustic beat phenomena by using a simple experimental setup, which can complement lessons in the classroom. The beats were created by the superposition of the waves generated by two tuning forks, with their natural frequencies previously characterized using different applications. After the characterization, we recorded the beats and analysed the oscillations in time and frequency.

  15. Dichotic beats of mistuned consonances.

    Science.gov (United States)

    Feeney, M P

    1997-10-01

    The beats of mistuned consonances (BMCs) result from the presentation of two sinusoids at frequencies slightly mistuned from a ratio of small integers. Several studies have suggested that the source of dichotic BMCs is an interaction within a binaural critical band. In one case the mechanism has been explained as an aural harmonic of the low-frequency tone (f1) creating binaural beats with the high-frequency tone (f2). The other explanation involves a binaural cross correlation between the excitation pattern of f1 and the contralateral f2--occurring within the binaural critical band centered at f2. This study examined the detection of dichotic BMCs for the octave and fifth. In one experiment with the octave, narrow-band noise centered at f2 was presented to one ear along with f1. The other ear was presented with f2. The noise was used to prevent interactions in the binaural critical band centered at f2. Dichotic BMCs were still detected under these conditions, suggesting that binaural interaction within a critical band does not explain the effect. Localization effects were also observed under this masking condition for phase reversals of tuned dichotic octave stimuli. These findings suggest a new theory of dichotic BMCs as a between-channel phase effect. The modified weighted-image model of localization [Stern and Trahiotis, in Auditory Physiology and Perception, edited by Y. Cazals, L. Demany, and K. Horner (Pergamon, Oxford, 1992), pp. 547-554] was used to provide an explanation of the between-channel mechanism.

  16. Ciliary body melanoma with optic nerve invasion.

    Science.gov (United States)

    al-Haddab, S; Hidayat, A; Tabbara, K F

    1990-01-01

    A case of melanoma of the ciliary body is presented. Initially the patient was diagnosed and treated for uveitis, but following CT scanning and ultrasound a tumour was detected and the eye enucleated. Histopathologically it was found that the tumour had invaded the optic nerve head, apparently via Cloquet's canal. Images PMID:2310725

  17. Modeling of Nonlinear Beat Signals of TAE's

    Science.gov (United States)

    Zhang, Bo; Berk, Herbert; Breizman, Boris; Zheng, Linjin

    2012-03-01

    Experiments on Alcator C-Mod reveal Toroidal Alfven Eigenmodes (TAE) together with signals at various beat frequencies, including those at twice the mode frequency. The beat frequencies are sidebands driven by quadratic nonlinear terms in the MHD equations. These nonlinear sidebands have not yet been quantified by any existing codes. We extend the AEGIS code to capture nonlinear effects by treating the nonlinear terms as a driving source in the linear MHD solver. Our goal is to compute the spatial structure of the sidebands for realistic geometry and q-profile, which can be directly compared with experiment in order to interpret the phase contrast imaging diagnostic measurements and to enable the quantitative determination of the Alfven wave amplitude in the plasma core

  18. Acoustical sensing of cardiomyocyte cluster beating

    Energy Technology Data Exchange (ETDEWEB)

    Tymchenko, Nina; Kunze, Angelika [Dept. of Applied Physics, Chalmers University of Technology, 412 96 Göteborg (Sweden); Dahlenborg, Kerstin [Cellectis, 413 46 Göteborg (Sweden); Svedhem, Sofia, E-mail: sofia.svedhem@chalmers.se [Dept. of Applied Physics, Chalmers University of Technology, 412 96 Göteborg (Sweden); Steel, Daniella [Cellectis, 413 46 Göteborg (Sweden)

    2013-06-14

    Highlights: •An example of the application of QCM-D to live cell studies. •Detection of human pluripotent stem cell-derived cardiomyocyte cluster beating. •Clusters were studied in a thin liquid film and in a large liquid volume. •The QCM-D beating profile provides an individual fingerprint of the hPS-CMCs. -- Abstract: Spontaneously beating human pluripotent stem cell-derived cardiomyocytes clusters (CMCs) represent an excellent in vitro tool for studies of human cardiomyocyte function and for pharmacological cardiac safety assessment. Such testing typically requires highly trained operators, precision plating, or large cell quantities, and there is a demand for real-time, label-free monitoring of small cell quantities, especially rare cells and tissue-like structures. Array formats based on sensing of electrical or optical properties of cells are being developed and in use by the pharmaceutical industry. A potential alternative to these techniques is represented by the quartz crystal microbalance with dissipation monitoring (QCM-D) technique, which is an acoustic surface sensitive technique that measures changes in mass and viscoelastic properties close to the sensor surface (from nm to μm). There is an increasing number of studies where QCM-D has successfully been applied to monitor properties of cells and cellular processes. In the present study, we show that spontaneous beating of CMCs on QCM-D sensors can be clearly detected, both in the frequency and the dissipation signals. Beating rates in the range of 66–168 bpm for CMCs were detected and confirmed by simultaneous light microscopy. The QCM-D beating profile was found to provide individual fingerprints of the hPS-CMCs. The presented results point towards acoustical assays for evaluation cardiotoxicity.

  19. Are there intracellular Ca2+ oscillations correlated with flagellar beating in human sperm? A three vs. two-dimensional analysis.

    Science.gov (United States)

    Corkidi, G; Montoya, F; Hernández-Herrera, P; Ríos-Herrera, W A; Müller, M F; Treviño, C L; Darszon, A

    2017-09-01

    Are there intracellular Ca2+ ([Ca2+]i) oscillations correlated with flagellar beating in human sperm? The results reveal statistically significant [Ca2+]i oscillations that are correlated with the human sperm flagellar beating frequency, when measured in three-dimensions (3D). Fast [Ca2+]i oscillations that are correlated to the beating flagellar frequency of cells swimming in a restricted volume have been detected in hamster sperm. To date, such findings have not been confirmed in any other mammalian sperm species. An important question that has remained regarding these observations is whether the fast [Ca2+]i oscillations are real or might they be due to remaining defocusing effects of the Z component arising from the 3D beating of the flagella. Healthy donors whose semen samples fulfill the WHO criteria between the age of 18-28 were selected. Cells from at least six different donors were utilized for analysis. Approximately the same number of experimental and control cells were analyzed. Motile cells were obtained by the swim-up technique and were loaded with Fluo-4 (Ca2+ sensitive dye) or with Calcein (Ca2+ insensitive dye). Ni2+ was used as a non-specific plasma membrane Ca2+ channel blocker. Fluorescence data and flagella position were acquired in 3D. Each cell was recorded for up to 5.6 s within a depth of 16 microns with a high speed camera (coupled to an image intensifier) acquiring at a rate of 3000 frames per second, while an oscillating objective vibrated at 90 Hz via a piezoelectric device. From these samples, eight experimental and nine control sperm cells were analyzed in both 2D and 3D. We have implemented a new system that allows [Ca2+]i measurements of the human sperm flagellum beating in 3D. These measurements reveal statistically significant [Ca2+]i oscillations that correlate with the flagellar beating frequency. These oscillations may arise from intracellular sources and/or Ca2+ transporters, as they were insensitive to external Ni2+, a non

  20. Healthcare performance and the effects of the binaural beats on human blood pressure and heart rate.

    Science.gov (United States)

    Carter, Calvin

    2008-01-01

    Binaural beats are the differences in two different frequencies (in the range of 30-1000 Hz). Binaural beats are played through headphones and are perceived by the superior olivary nucleus of each hemisphere of the brain. The brain perceives the binaural beat and resonates to its frequency (frequency following response). Once the brain is in tune with the binaural beat it produces brainwaves of that frequency altering the listener's state of mind. In this experiment, the effects of the beta and theta binaural beat on human blood pressure and pulse were studied. Using headphones, three sounds were played for 7 minutes each to 12 participants: the control,- the sound of a babbling brook (the background sound to the two binaural beats), the beta binaural beat (20 Hz), and the theta binaural beat (7 Hz). Blood pressure and pulse were recorded before and after each sound was played. Each participant was given 2 minutes in-between each sound. The results showed that the control and the two binaural beats did not affect the 12 participant's blood pressure or pulse (p > 0.05). One reason for this may be that the sounds were not played long enough for the brain to either perceive and/or resonate to the frequency. Another reason why the sounds did not affect blood pressure and pulse may be due to the participant's age since older brains may not perceive the binaural beats as well as younger brains.

  1. Human auditory steady state responses to binaural and monaural beats.

    Science.gov (United States)

    Schwarz, D W F; Taylor, P

    2005-03-01

    Binaural beat sensations depend upon a central combination of two different temporally encoded tones, separately presented to the two ears. We tested the feasibility to record an auditory steady state evoked response (ASSR) at the binaural beat frequency in order to find a measure for temporal coding of sound in the human EEG. We stimulated each ear with a distinct tone, both differing in frequency by 40Hz, to record a binaural beat ASSR. As control, we evoked a beat ASSR in response to both tones in the same ear. We band-pass filtered the EEG at 40Hz, averaged with respect to stimulus onset and compared ASSR amplitudes and phases, extracted from a sinusoidal non-linear regression fit to a 40Hz period average. A 40Hz binaural beat ASSR was evoked at a low mean stimulus frequency (400Hz) but became undetectable beyond 3kHz. Its amplitude was smaller than that of the acoustic beat ASSR, which was evoked at low and high frequencies. Both ASSR types had maxima at fronto-central leads and displayed a fronto-occipital phase delay of several ms. The dependence of the 40Hz binaural beat ASSR on stimuli at low, temporally coded tone frequencies suggests that it may objectively assess temporal sound coding ability. The phase shift across the electrode array is evidence for more than one origin of the 40Hz oscillations. The binaural beat ASSR is an evoked response, with novel diagnostic potential, to a signal that is not present in the stimulus, but generated within the brain.

  2. Photoreceptor Sensory Cilium: Traversing the Ciliary Gate

    Directory of Open Access Journals (Sweden)

    Hemant Khanna

    2015-10-01

    Full Text Available Cilia are antenna-like extensions of the plasma membrane found in nearly all cell types. In the retina of the eye, photoreceptors develop unique sensory cilia. Not much was known about the mechanisms underlying the formation and function of photoreceptor cilia, largely because of technical limitations and the specific structural and functional modifications that cannot be modeled in vitro. With recent advances in microscopy techniques and molecular and biochemical approaches, we are now beginning to understand the molecular basis of photoreceptor ciliary architecture, ciliary function and its involvement in human diseases. Here, I will discuss the studies that have revealed new knowledge of how photoreceptor cilia regulate their identity and function while coping with high metabolic and trafficking demands associated with processing light signal.

  3. Ciliary neurotrophic factor is an endogenous pyrogen.

    OpenAIRE

    Shapiro, L; Zhang, X X; Rupp, R G; Wolff, S M; Dinarello, C A

    1993-01-01

    Fever is initiated by the action of polypeptide cytokines called endogenous pyrogens, which are produced by the host during inflammation, trauma, or infection and which elevate the thermoregulatory set point in the hypothalamus. Ciliary neurotrophic factor (CNTF) supports the differentiation and survival of central and peripheral neurons. We describe the activity of CNTF as intrinsically pyrogenic in the rabbit. CNTF induced a monophasic fever which rose rapidly (within the first 12 min) foll...

  4. Cellular Mechanisms of Ciliary Length Control

    Directory of Open Access Journals (Sweden)

    Jacob Keeling

    2016-01-01

    Full Text Available Cilia and flagella are evolutionarily conserved, membrane-bound, microtubule-based organelles on the surface of most eukaryotic cells. They play important roles in coordinating a variety of signaling pathways during growth, development, cell mobility, and tissue homeostasis. Defects in ciliary structure or function are associated with multiple human disorders called ciliopathies. These diseases affect diverse tissues, including, but not limited to the eyes, kidneys, brain, and lungs. Many processes must be coordinated simultaneously in order to initiate ciliogenesis. These include cell cycle, vesicular trafficking, and axonemal extension. Centrioles play a central role in both cell cycle progression and ciliogenesis, making the transition between basal bodies and mitotic spindle organizers integral to both processes. The maturation of centrioles involves a functional shift from cell division toward cilium nucleation which takes place concurrently with its migration and fusion to the plasma membrane. Several proteinaceous structures of the distal appendages in mother centrioles are required for this docking process. Ciliary assembly and maintenance requires a precise balance between two indispensable processes; so called assembly and disassembly. The interplay between them determines the length of the resulting cilia. These processes require a highly conserved transport system to provide the necessary substances at the tips of the cilia and to recycle ciliary turnover products to the base using a based microtubule intraflagellar transport (IFT system. In this review; we discuss the stages of ciliogenesis as well as mechanisms controlling the lengths of assembled cilia.

  5. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity

    OpenAIRE

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A.; Leonessa, Alexander

    2016-01-01

    Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, hav...

  6. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity.

    Directory of Open Access Journals (Sweden)

    Christine Beauchene

    Full Text Available Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, have not been well studied. Furthermore, no studies have evaluated the effects of binaural beats on brain connectivity during working memory tasks. In this study, we determined the effects of different acoustic stimulation conditions on participant response accuracy and cortical network topology, as measured by EEG recordings, during a visuospatial working memory task. Three acoustic stimulation control conditions and three binaural beat stimulation conditions were used: None, Pure Tone, Classical Music, 5Hz binaural beats, 10Hz binaural beats, and 15Hz binaural beats. We found that listening to 15Hz binaural beats during a visuospatial working memory task not only increased the response accuracy, but also modified the strengths of the cortical networks during the task. The three auditory control conditions and the 5Hz and 10Hz binaural beats all decreased accuracy. Based on graphical network analyses, the cortical activity during 15Hz binaural beats produced networks characteristic of high information transfer with consistent connection strengths throughout the visuospatial working memory task.

  7. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity.

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A; Leonessa, Alexander

    2016-01-01

    Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, have not been well studied. Furthermore, no studies have evaluated the effects of binaural beats on brain connectivity during working memory tasks. In this study, we determined the effects of different acoustic stimulation conditions on participant response accuracy and cortical network topology, as measured by EEG recordings, during a visuospatial working memory task. Three acoustic stimulation control conditions and three binaural beat stimulation conditions were used: None, Pure Tone, Classical Music, 5Hz binaural beats, 10Hz binaural beats, and 15Hz binaural beats. We found that listening to 15Hz binaural beats during a visuospatial working memory task not only increased the response accuracy, but also modified the strengths of the cortical networks during the task. The three auditory control conditions and the 5Hz and 10Hz binaural beats all decreased accuracy. Based on graphical network analyses, the cortical activity during 15Hz binaural beats produced networks characteristic of high information transfer with consistent connection strengths throughout the visuospatial working memory task.

  8. Asymmetric wavefront aberrations and pupillary shapes induced by electrical stimulation of ciliary nerve in cats measured with compact wavefront aberrometer.

    Directory of Open Access Journals (Sweden)

    Suguru Miyagawa

    Full Text Available To investigate the changes in the wavefront aberrations and pupillary shape in response to electrical stimulation of the branches of the ciliary nerves in cats. Seven eyes of seven cats were studied under general anesthesia. Trains of monophasic pulses (current, 0.1 to 1.0 mA; duration, 0.5 ms/phase; frequency, 5 to 40 Hz were applied to the lateral or medial branch of the short ciliary nerve near the posterior pole of the eye. A pair of electrodes was hooked onto one or both branch of the short ciliary nerve. The electrodes were placed about 5 mm from the scleral surface. The wavefront aberrations were recorded continuously for 2 seconds before, 8 seconds during, and for 20 seconds after the electrical stimulation. The pupillary images were simultaneously recorded during the stimulation period. Both the wavefront aberrations and the pupillary images were obtained 10 times/sec with a custom-built wavefront aberrometer. The maximum accommodative amplitude was 1.19 diopters (D produced by electrical stimulation of the short ciliary nerves. The latency of the accommodative changes was very short, and the accommodative level gradually increased up to 4 seconds and reached a plateau. When only one branch of the ciliary nerve was stimulated, the pupil dilated asymmetrically, and the oblique astigmatism and one of the asymmetrical wavefront terms was also altered. Our results showed that the wavefront aberrations and pupillary dilations can be measured simultaneously and serially with a compact wavefront aberrometer. The asymmetric pupil dilation and asymmetric changes of the wavefront aberrations suggest that each branch of the ciliary nerve innervates specific segments of the ciliary muscle and dilator muscle of the pupil.

  9. Auditory beat stimulation and its effects on cognition and mood states

    Directory of Open Access Journals (Sweden)

    Leila eChaieb

    2015-05-01

    Full Text Available Auditory beat stimulation may be a promising new tool for the manipulation of cognitive processes and the modulation of mood-states. Here we aim to review the literature examining the most current applications of auditory beat stimulation and its targets. We give a brief overview of research on auditory steady-state responses and its relationship to auditory beat stimulation. We have summarized relevant studies investigating the neurophysiological changes related to auditory beat stimulation and how they impact upon the design of appropriate stimulation protocols. Focusing on binaural beat stimulation, we then discuss the role of monaural and binaural beat frequencies in cognition and mood-states, in addition to their efficacy in targeting disease symptoms. We aim to highlight important points concerning stimulation parameters and try to address why there are often contradictory findings with regard to the outcomes of auditory beat stimulation.

  10. Ciliary metachronal wave propagation on the compliant surface of Paramecium cells.

    Science.gov (United States)

    Narematsu, Naoki; Quek, Raymond; Chiam, Keng-Hwee; Iwadate, Yoshiaki

    2015-12-01

    Ciliary movements in protozoa exhibit metachronal wave-like coordination, in which a constant phase difference is maintained between adjacent cilia. It is at present generally thought that metachronal waves require hydrodynamic coupling between adjacent cilia and the extracellular fluid. To test this hypothesis, we aspirated a Paramecium cell using a micropipette which completely sealed the surface of the cell such that no fluid could pass through the micropipette. Thus, the anterior and the posterior regions of the cell were hydrodynamically decoupled. Nevertheless, we still observed that metachronal waves continued to propagate from the anterior to the posterior ends of the cell, suggesting that in addition to hydrodynamic coupling, there are other mechanisms that can also transmit the metachronal waves. Such transmission was also observed in computational modeling where the fluid was fully decoupled between two partitions of a beating ciliary array. We also imposed cyclic stretching on the surface of live Paramecium cells and found that metachronal waves persisted in the presence of cyclic stretching. This demonstrated that, in addition to hydrodynamic coupling, a compliant substrate can also play a critical role in mediating the propagation of metachronal waves. © 2015 Wiley Periodicals, Inc.

  11. Beat-Frequency/Microsphere Medical Ultrasonic Imaging

    Science.gov (United States)

    Yost, William T.; Cantrell, John H.; Pretlow, Robert A., III

    1995-01-01

    Medical ultrasonic imaging system designed to provide quantitative data on various flows of blood in chambers, blood vessels, muscles, and tissues of heart. Sensitive enough to yield readings on flows of blood in heart even when microspheres used as ultrasonic contrast agents injected far from heart and diluted by circulation of blood elsewhere in body.

  12. Direct Visualization of Mechanical Beats by Means of an Oscillating Smartphone

    Science.gov (United States)

    Giménez, Marcos H.; Salinas, Isabel; Monsoriu, Juan A.; Castro-Palacio, Juan C.

    2017-10-01

    The resonance phenomenon is widely known in physics courses. Qualitatively speaking, resonance takes place in a driven oscillating system whenever the frequency approaches the natural frequency, resulting in maximal oscillatory amplitude. Very closely related to resonance is the phenomenon of mechanical beating, which occurs when the driving and natural frequencies of the system are slightly different. The frequency of the beat is just the difference of the natural and driving frequencies. Beats are very familiar in acoustic systems. There are several works in this journal on visualizing the beats in acoustic systems. For instance, the microphone and the speaker of two mobile devices were used in previous work to analyze the acoustic beats produced by two signals of close frequencies. The formation of beats can also be visualized in mechanical systems, such as a mass-spring system or a double-driven string. Here, the mechanical beats in a smartphone-spring system are directly visualized in a simple way. The frequency of the beats is measured by means of the acceleration sensor of a smartphone, which hangs from a spring attached to a mechanical driver. This laboratory experiment is suitable for both high school and first-year university physics courses.

  13. Long-term outcome of Tunisian children with primary ciliary ...

    African Journals Online (AJOL)

    Background: Primary ciliary dyskinesia (PCD) is rare. Its diagnosis requires experienced specialists and expensive infrastructure. Its prognosis is variable. Objective: To study the long-term outcome of PCD in Tunisian children with ciliary ultra-structure defects detected by electron microscope. Methods: Covering a period of ...

  14. The Pediatric Choroidal and Ciliary Body Melanoma Study

    DEFF Research Database (Denmark)

    Al-Jamal, Rana'a T; Cassoux, Nathalie; Desjardins, Laurence

    2016-01-01

    PURPOSE: To collect comprehensive data on choroidal and ciliary body melanoma (CCBM) in children and to validate hypotheses regarding pediatric CCBM: children younger than 18 years, males, and those without ciliary body involvement (CBI) have more favorable survival prognosis than young adults 18...

  15. Beat to beat variability in cardiovascular variables: noise or music?

    Science.gov (United States)

    Appel, M. L.; Berger, R. D.; Saul, J. P.; Smith, J. M.; Cohen, R. J.

    1989-01-01

    Cardiovascular variables such as heart rate, arterial blood pressure, stroke volume and the shape of electrocardiographic complexes all fluctuate on a beat to beat basis. These fluctuations have traditionally been ignored or, at best, treated as noise to be averaged out. The variability in cardiovascular signals reflects the homeodynamic interplay between perturbations to cardiovascular function and the dynamic response of the cardiovascular regulatory systems. Modern signal processing techniques provide a means of analyzing beat to beat fluctuations in cardiovascular signals, so as to permit a quantitative, noninvasive or minimally invasive method of assessing closed loop hemodynamic regulation and cardiac electrical stability. This method promises to provide a new approach to the clinical diagnosis and management of alterations in cardiovascular regulation and stability.

  16. Analysis of the forces acting on beating cilia

    International Nuclear Information System (INIS)

    Sangani, Ashok S; Vidyadharan, Jyothish; Foster, Kenneth W

    2016-01-01

    Detailed analysis of the forces acting on a uniform-diameter beating cilium is carried out to determine the moment generated by the inter-doublet forces acting along the length of a cilium and the results are compared with the sliding-control theory according to which the moment is a function of the interdoublet sliding. In the central part of the cilium the inter-doublet forces are found to be proportional to the inter-doublet sliding. However, in spite of the uniformity of the diameter of the cilium, the proportionality constant, known as the dynamic stiffness, is not constant along its entire length. Significant variations are observed in the regions both near the tip of the cilium and proximal to the cell body. In the tip region the magnitude of the dynamic stiffness is found to decrease. This decrease is probably due to decrease in the number density of the molecular motors in that region and in the number of doublet microtubules. The behavior in the proximal region, on the other hand, does not appear to be well described by the sliding control theory. Our analysis therefore suggests that the dynamics of ciliary beating cannot be adequately described by a simple sliding-control theory with constant dynamic stiffness. Our analysis suggests that the cilium is differentiated into a basal region optimized for the creation of a wave and a central region optimized to support a traveling wave that provides the thrust for the cell. (paper)

  17. Detection of heart beats in multimodal data: a robust beat-to-beat interval estimation approach.

    Science.gov (United States)

    Antink, Christoph Hoog; Brüser, Christoph; Leonhardt, Steffen

    2015-08-01

    The heart rate and its variability play a vital role in the continuous monitoring of patients, especially in the critical care unit. They are commonly derived automatically from the electrocardiogram as the interval between consecutive heart beat. While their identification by QRS-complexes is straightforward under ideal conditions, the exact localization can be a challenging task if the signal is severely contaminated with noise and artifacts. At the same time, other signals directly related to cardiac activity are often available. In this multi-sensor scenario, methods of multimodal sensor-fusion allow the exploitation of redundancies to increase the accuracy and robustness of beat detection.In this paper, an algorithm for the robust detection of heart beats in multimodal data is presented. Classic peak-detection is augmented by robust multi-channel, multimodal interval estimation to eliminate false detections and insert missing beats. This approach yielded a score of 90.70 and was thus ranked third place in the PhysioNet/Computing in Cardiology Challenge 2014: Robust Detection of Heart Beats in Muthmodal Data follow-up analysis.In the future, the robust beat-to-beat interval estimator may directly be used for the automated processing of multimodal patient data for applications such as diagnosis support and intelligent alarming.

  18. Response of cat inferior colliculus neurons to binaural beat stimuli: possible mechanisms for sound localization.

    Science.gov (United States)

    Kuwada, S; Yin, T C; Wickesberg, R E

    1979-11-02

    The interaural phase sensitivity of neurons was studied through the use of binaural beat stimuli. The response of most cells was phase-locked to the beat frequency, which provides a possible neural correlate to the human sensation of binaural beats. In addition, this stimulus allowed the direction and rate of interaural phase change to be varied. Some neurons in our sample responded selectively to manipulations of these two variables, which suggests a sensitivity to direction or speed of movement.

  19. ECOLE POLYTECHNIQUE: Acceleration by plasma beat waves

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    An experiment by a multi-disciplinary team including laser, plasma, accelerator and particle detector specialists at the École Polytechnique, Palaiseau, France, has confirmed the principle of particle acceleration by the 'beating' of laser waves. The first accelerated electrons were detected in May 1994, just after the apparatus had been completely assembled, during the subsequent set of experiments in July, and again in January. In the continual quest for new acceleration methods, such ideas had been proposed for several decades, but it was only about ten years ago that experimental verification of these effects began. In existing accelerators using radiofrequency cavities the electric field is limited to some hundred megavolts per metre, beyond which breakdowns occur. The joint use of power lasers and plasmas, however, should make it possible to generate fields very much greater than a GV/m. The light wave fulfils the same purpose as radiofrequency and the material medium required to couple the electromagnetic energy to the particle beam is provided by the plasma which - already fully ionized - is not destroyed by a breakdown. In the wave-beating method, proposed in 1979 by Dawson and Tajima, two laser waves of adjacent frequencies are transmitted and produce 'beats'. If the frequency of these is equal to the natural oscillation frequency of the plasma electrons, there is resonant energy transfer. The resultant longitudinal electric field is propagated at slightly below the speed of light and may be used to accelerate particles injected into the plasma in the right phase

  20. A quantitative electroencephalographic study of meditation and binaural beat entrainment.

    Science.gov (United States)

    Lavallee, Christina F; Koren, Stanley A; Persinger, Michael A

    2011-04-01

    The study objective was to determine the quantitative electroencephalographic correlates of meditation, as well as the effects of hindering (15 Hz) and facilitative (7 Hz) binaural beats on the meditative process. The study was a mixed design, with experience of the subject as the primary between-subject measure and power of the six classic frequency bands (δ, θ, low α, high α, β, γ), neocortical lobe (frontal, temporal, parietal, occipital), hemisphere (left, right), and condition (meditation only, meditation with 7-Hz beats, meditation with 15-Hz beats) as the within-subject measures. The study was conducted at Laurentian University in Sudbury, Ontario, Canada. The subjects comprised novice (mean of 8 months experience) and experienced (mean of 18 years experience) meditators recruited from local meditation groups. Experimental manipulation included application of hindering and facilitative binaural beats to the meditative process. Experienced meditators displayed increased left temporal lobe δ power when the facilitative binaural beats were applied, whereas the effect was not observed for the novice subjects in this condition. When the hindering binaural beats were introduced, the novice subjects consistently displayed more γ power than the experienced subjects over the course of their meditation, relative to baseline. Based on the results of this study, novice meditators were not able to maintain certain levels of θ power in the occipital regions when hindering binaural beats were presented, whereas when the facilitative binaural beats were presented, the experienced meditators displayed increased θ power in the left temporal lobe. These results suggest that the experienced meditators have developed techniques over the course of their meditation practice to counter hindering environmental stimuli, whereas the novice meditators have not yet developed those techniques.

  1. Human sperm steer with second harmonics of the flagellar beat.

    Science.gov (United States)

    Saggiorato, Guglielmo; Alvarez, Luis; Jikeli, Jan F; Kaupp, U Benjamin; Gompper, Gerhard; Elgeti, Jens

    2017-11-10

    Sperm are propelled by bending waves traveling along their flagellum. For steering in gradients of sensory cues, sperm adjust the flagellar waveform. Symmetric and asymmetric waveforms result in straight and curved swimming paths, respectively. Two mechanisms causing spatially asymmetric waveforms have been proposed: an average flagellar curvature and buckling. We image flagella of human sperm tethered with the head to a surface. The waveform is characterized by a fundamental beat frequency and its second harmonic. The superposition of harmonics breaks the beat symmetry temporally rather than spatially. As a result, sperm rotate around the tethering point. The rotation velocity is determined by the second-harmonic amplitude and phase. Stimulation with the female sex hormone progesterone enhances the second-harmonic contribution and, thereby, modulates sperm rotation. Higher beat frequency components exist in other flagellated cells; therefore, this steering mechanism might be widespread and could inspire the design of synthetic microswimmers.

  2. More attentional focusing through binaural beats: evidence from the global-local task.

    Science.gov (United States)

    Colzato, Lorenza S; Barone, Hayley; Sellaro, Roberta; Hommel, Bernhard

    2017-01-01

    A recent study showed that binaural beats have an impact on the efficiency of allocating attention over time. We were interested to see whether this impact affects attentional focusing or, even further, the top-down control over irrelevant information. Healthy adults listened to gamma-frequency (40 Hz) binaural beats, which are assumed to increase attentional concentration, or a constant tone of 340 Hz (control condition) for 3 min before and during a global-local task. While the size of the congruency effect (indicating the failure to suppress task-irrelevant information) was unaffected by the binaural beats, the global-precedence effect (reflecting attentional focusing) was considerably smaller after gamma-frequency binaural beats than after the control condition. Our findings suggest that high-frequency binaural beats bias the individual attentional processing style towards a reduced spotlight of attention.

  3. Effects of single cycle binaural beat duration on auditory evoked potentials.

    Science.gov (United States)

    Mihajloski, Todor; Bohorquez, Jorge; Özdamar, Özcan

    2014-01-01

    Binaural beat (BB) illusions are experienced as continuous central pulsations when two sounds with slightly different frequencies are delivered to each ear. It has been shown that steady-state auditory evoked potentials (AEPs) to BBs can be captured and investigated. The authors recently developed a new method of evoking transient AEPs to binaural beats using frequency modulated stimuli. This methodology was able to create single BBs in predetermined intervals with varying carrier frequencies. This study examines the effects of the BB duration and the frequency modulating component of the stimulus on the binaural beats and their evoked potentials. Normal hearing subjects were tested with a set of four durations (25, 50, 100, and 200 ms) with two stimulation configurations, binaural dichotic (binaural beats) and diotic (frequency modulation). The results obtained from the study showed that out of the given durations, the 100 ms beat, was capable of evoking the largest amplitude responses. The frequency modulation effect showed a decrease in peak amplitudes with increasing beat duration until their complete disappearance at 200 ms. Even though, at 200 ms, the frequency modulation effects were not present, the binaural beats were still perceived and captured as evoked potentials.

  4. An international registry for primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Werner, Claudius; Lablans, Martin; Ataian, Maximilian

    2016-01-01

    Primary ciliary dyskinesia (PCD) is a rare autosomal recessive disorder leading to chronic upper and lower airway disease. Fundamental data on epidemiology, clinical presentation, course and treatment strategies are lacking in PCD. We have established an international PCD registry to realise...... an unmet need for an international platform to systematically collect data on incidence, clinical presentation, treatment and disease course.The registry was launched in January 2014. We used internet technology to ensure easy online access using a web browser under www.pcdregistry.eu. Data from 201...... methods in addition to classical clinical symptoms. Preliminary analysis of lung function data demonstrated a mean annual decline of percentage predicted forced expiratory volume in 1 s of 0.59% (95% CI 0.98-0.22).Here, we present the development of an international PCD registry as a new promising tool...

  5. Negative regulation of ciliary length by ciliary male germ cell-associated kinase (Mak) is required for retinal photoreceptor survival.

    Science.gov (United States)

    Omori, Yoshihiro; Chaya, Taro; Katoh, Kimiko; Kajimura, Naoko; Sato, Shigeru; Muraoka, Koichiro; Ueno, Shinji; Koyasu, Toshiyuki; Kondo, Mineo; Furukawa, Takahisa

    2010-12-28

    Cilia function as cell sensors in many organs, and their disorders are referred to as "ciliopathies." Although ciliary components and transport machinery have been well studied, regulatory mechanisms of ciliary formation and maintenance are poorly understood. Here we show that male germ cell-associated kinase (Mak) regulates retinal photoreceptor ciliary length and subcompartmentalization. Mak was localized both in the connecting cilia and outer-segment axonemes of photoreceptor cells. In the Mak-null retina, photoreceptors exhibit elongated cilia and progressive degeneration. We observed accumulation of intraflagellar transport 88 (IFT88) and IFT57, expansion of kinesin family member 3A (Kif3a), and acetylated α-tubulin signals in the Mak-null photoreceptor cilia. We found abnormal rhodopsin accumulation in the Mak-null photoreceptor cell bodies at postnatal day 14. In addition, overexpression of retinitis pigmentosa 1 (RP1), a microtubule-associated protein localized in outer-segment axonemes, induced ciliary elongation, and Mak coexpression rescued excessive ciliary elongation by RP1. The RP1 N-terminal portion induces ciliary elongation and increased intensity of acetylated α-tubulin labeling in the cells and is phosphorylated by Mak. These results suggest that Mak is essential for the regulation of ciliary length and is required for the long-term survival of photoreceptors.

  6. Beat map drawing method for large oriental bell based on operational deflection shape method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joong Hyeok; Kim, Seock Hyun [Dept. of Advanced Mechanical Engineering, Kangwon National University, Chuncheon (Korea, Republic of); Park, In Seok [TB Tires Development 1 Team, R and D Center, Kumho Tire, Yongin (Korea, Republic of)

    2016-10-15

    Oriental bells produce a peculiar sound in the form of beats, which are periodic repetitions of strong and weak sounds. A beating sound with a proper period gives the illusion of the bell being alive and breathing. To produce a good beating sound, appropriate modal parameters are required for beat tuning after casting the bell. Conventionally, modal parameters were extracted using frequency response functions of the excitation and response signals. However, a large oriental bell is usually struck by a heavy wooden hammer and hence, only the response signal can be measured. In this study, we extract the modal parameters using the response signal only and employ the data to predict the beat properties of the bell sound. Finally, the validity of the predicted beat properties is experimentally verified for a large oriental bell.

  7. Prevention of adenosine A2A receptor activation diminishes beat-to-beat alternation in human atrial myocytes.

    Science.gov (United States)

    Molina, Cristina E; Llach, Anna; Herraiz-Martínez, Adela; Tarifa, Carmen; Barriga, Montserrat; Wiegerinck, Rob F; Fernandes, Jacqueline; Cabello, Nuria; Vallmitjana, Alex; Benitéz, Raúl; Montiel, José; Cinca, Juan; Hove-Madsen, Leif

    2016-01-01

    Atrial fibrillation (AF) has been associated with increased spontaneous calcium release from the sarcoplasmic reticulum and linked to increased adenosine A2A receptor (A2AR) expression and activation. Here we tested whether this may favor atrial arrhythmogenesis by promoting beat-to-beat alternation and irregularity. Patch-clamp and confocal calcium imaging was used to measure the beat-to-beat response of the calcium current and transient in human atrial myocytes. Responses were classified as uniform, alternating or irregular and stimulation of Gs-protein coupled receptors decreased the frequency where a uniform response could be maintained from 1.0 ± 0.1 to 0.6 ± 0.1 Hz; p < 0.01 for beta-adrenergic receptors and from 1.4 ± 0.1 to 0.5 ± 0.1 Hz; p < 0.05 for A2ARs. The latter was linked to increased spontaneous calcium release and after-depolarizations. Moreover, A2AR activation increased the fraction of non-uniformly responding cells in HL-1 myocyte cultures from 19 ± 3 to 51 ± 9 %; p < 0.02, and electrical mapping in perfused porcine atria revealed that adenosine induced electrical alternans at longer cycle lengths, doubled the fraction of electrodes showing alternation, and increased the amplitude of alternations. Importantly, protein kinase A inhibition increased the highest frequency where uniform responses could be maintained from 0.84 ± 0.12 to 1.86 ± 0.11 Hz; p < 0.001 and prevention of A2AR-activation with exogenous adenosine deaminase selectively increased the threshold from 0.8 ± 0.1 to 1.2 ± 0.1 Hz; p = 0.001 in myocytes from patients with AF. In conclusion, A2AR-activation promotes beat-to-beat irregularities in the calcium transient in human atrial myocytes, and prevention of A2AR activation may be a novel means to maintain uniform beat-to-beat responses at higher beating frequencies in patients with atrial fibrillation.

  8. The effect of binaural beats on verbal working memory and cortical connectivity

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A.; Leonessa, Alexander

    2017-04-01

    Objective. Synchronization in activated regions of cortical networks affect the brain’s frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain’s response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat frequency, which may act to synchronize cortical oscillations. Neural synchrony is particularly important for working memory processes, the system controlling online organization and retention of information for successful goal-directed behavior. Therefore, manipulation of synchrony via binaural beats provides a unique window into working memory and associated connectivity of cortical networks. Approach. In this study, we examined the effects of different acoustic stimulation conditions during an N-back working memory task, and we measured participant response accuracy and cortical network topology via EEG recordings. Six acoustic stimulation conditions were used: None, Pure Tone, Classical Music, 5 Hz binaural beats, 10 Hz binaural beats, and 15 Hz binaural beats. Main results. We determined that listening to 15 Hz binaural beats during an N-Back working memory task increased the individual participant’s accuracy, modulated the cortical frequency response, and changed the cortical network connection strengths during the task. Only the 15 Hz binaural beats produced significant change in relative accuracy compared to the None condition. Significance. Listening to 15 Hz binaural beats during the N-back task activated salient frequency bands and produced networks characterized by higher information transfer as compared to other auditory stimulation conditions.

  9. The effect of binaural beats on verbal working memory and cortical connectivity.

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A; Leonessa, Alexander

    2017-04-01

    Synchronization in activated regions of cortical networks affect the brain's frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain's response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat frequency, which may act to synchronize cortical oscillations. Neural synchrony is particularly important for working memory processes, the system controlling online organization and retention of information for successful goal-directed behavior. Therefore, manipulation of synchrony via binaural beats provides a unique window into working memory and associated connectivity of cortical networks. In this study, we examined the effects of different acoustic stimulation conditions during an N-back working memory task, and we measured participant response accuracy and cortical network topology via EEG recordings. Six acoustic stimulation conditions were used: None, Pure Tone, Classical Music, 5 Hz binaural beats, 10 Hz binaural beats, and 15 Hz binaural beats. We determined that listening to 15 Hz binaural beats during an N-Back working memory task increased the individual participant's accuracy, modulated the cortical frequency response, and changed the cortical network connection strengths during the task. Only the 15 Hz binaural beats produced significant change in relative accuracy compared to the None condition. Listening to 15 Hz binaural beats during the N-back task activated salient frequency bands and produced networks characterized by higher information transfer as compared to other auditory stimulation conditions.

  10. Intracranial electroencephalography power and phase synchronization changes during monaural and binaural beat stimulation.

    Science.gov (United States)

    Becher, Ann-Katrin; Höhne, Marlene; Axmacher, Nikolai; Chaieb, Leila; Elger, Christian E; Fell, Juergen

    2015-01-01

    Auditory stimulation with monaural or binaural auditory beats (i.e. sine waves with nearby frequencies presented either to both ears or to each ear separately) represents a non-invasive approach to influence electrical brain activity. It is still unclear exactly which brain sites are affected by beat stimulation. In particular, an impact of beat stimulation on mediotemporal brain areas could possibly provide new options for memory enhancement or seizure control. Therefore, we examined how electroencephalography (EEG) power and phase synchronization are modulated by auditory stimulation with beat frequencies corresponding to dominant EEG rhythms based on intracranial recordings in presurgical epilepsy patients. Monaural and binaural beat stimuli with beat frequencies of 5, 10, 40 and 80 Hz and non-superposed control signals were administered with low amplitudes (60 dB SPL) and for short durations (5 s). EEG power was intracranially recorded from mediotemporal, temporo-basal and temporo-lateral and surface sites. Evoked and total EEG power and phase synchronization during beat vs. control stimulation were compared by the use of Bonferroni-corrected non-parametric label-permutation tests. We found that power and phase synchronization were significantly modulated by beat stimulation not only at temporo-basal, temporo-lateral and surface sites, but also at mediotemporal sites. Generally, more significant decreases than increases were observed. The most prominent power increases were seen after stimulation with monaural 40-Hz beats. The most pronounced power and synchronization decreases resulted from stimulation with monaural 5-Hz and binaural 80-Hz beats. Our results suggest that beat stimulation offers a non-invasive approach for the modulation of intracranial EEG characteristics. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  11. Beating HF waves to generate VLF waves in the ionosphere

    Science.gov (United States)

    Kuo, Spencer; Snyder, Arnold; Kossey, Paul; Chang, Chia-Lie; Labenski, John

    2012-03-01

    Beat-wave generation of very low frequency (VLF) waves by two HF heaters in the ionosphere is formulated theoretically and demonstrated experimentally. The heater-induced differential thermal pressure force and ponderomotive force, which dominate separately in the D and F regions of the ionosphere, drive an electron current for the VLF emission. A comparison, applying appropriate ionospheric parameters shows that the ponderomotive force dominates in beat-wave generation of VLF waves. Three experiments, one in the nighttime in the absence of D and E layers and two in the daytime in the presence of D and E layers, were performed. X mode HF heaters of slightly different frequencies were transmitted at CW full power. VLF waves at 10 frequencies ranging from 3.5 to 21.5 kHz were generated. The frequency dependencies of the daytime and nighttime radiation intensities are quite similar, but the nighttime radiation is much stronger than the daytime one at the same radiation frequency. The intensity ratio is as large as 9 dB at 11.5 kHz. An experiment directly comparing VLF waves generated by the beat-wave approach and by the amplitude modulation (AM) approach was also conducted. The results rule out the likely contribution of the AM mechanism acting on the electrojet and indicate that beat-wave in the VLF range prefers to be generated in the F region of the ionosphere through the ponderomotive nonlinearity, consistent with the theory. In the nighttime experiment, the ionosphere was underdense to the HF heaters, suggesting a likely setting for effective beat-wave generation of VLF waves by the HF heaters.

  12. Ciliary and non-ciliary expression and function of PACRG during vertebrate development

    Directory of Open Access Journals (Sweden)

    Thumberger Thomas

    2012-08-01

    Full Text Available Abstract Background Park2-co-regulated gene (PACRG is evolutionarily highly conserved from green algae to mammals. In Chlamydomonas and trypanosomes, the PACRG protein associates with flagella. Loss of PACRG results in shortened or absent flagella. In mouse the PACRG protein is required for spermatogenesis. The purpose of the present study was to analyze (1 the expression patterns of PACRG during vertebrate embryogenesis, and (2 whether the PACRG protein was required for left-right (LR axis specification through cilia-driven leftward flow in Xenopus laevis. Methods PACRG cDNAs were cloned and expression was analyzed during early embryonic development of Xenopus, mouse, rabbit and zebrafish. Antisense morpholino oligonucleotide (MO mediated gene knockdown was applied in Xenopus to investigate LR development at the level of tissue morphology, leftward flow and asymmetric marker gene expression, using timelapse videography, scanning electron microscopy (SEM and whole-mount in situ hybridization. Results were statistically evaluated using Wilcoxon paired and χ2 tests. Results PACRG mRNA expression was found in cells and tissues harboring cilia throughout the vertebrates. Highly localized expression was also detected in the brain. During early development, PACRG was specifically localized to epithelia where leftward flow arises, that is, the gastrocoel roof plate (GRP in Xenopus, the posterior notochord (PNC in mammals and Kupffer’s vesicle (KV in zebrafish. Besides its association with ciliary axonemes, subcellular localization of PACRG protein was found around the nucleus and in a spotty pattern in the cytoplasm. A green fluorescent protein (GFP fusion construct preferentially labeled cilia, rendering PACRG a versatile marker for live imaging. Loss-of-function in the frog resulted dose dependently in LR, neural tube closure and gastrulation defects, representing ciliary and non-ciliary functions of PACRG. Conclusions The PACRG protein is a novel

  13. HEART: an automated beat-to-beat cardiovascular analysis package using Matlab.

    Science.gov (United States)

    Schroeder, M J Mark J; Perreault, Bill; Ewert, D L Daniel L; Koenig, S C Steven C

    2004-07-01

    A computer program is described for beat-to-beat analysis of cardiovascular parameters from high-fidelity pressure and flow waveforms. The Hemodynamic Estimation and Analysis Research Tool (HEART) is a post-processing analysis software package developed in Matlab that enables scientists and clinicians to document, load, view, calibrate, and analyze experimental data that have been digitally saved in ascii or binary format. Analysis routines include traditional hemodynamic parameter estimates as well as more sophisticated analyses such as lumped arterial model parameter estimation and vascular impedance frequency spectra. Cardiovascular parameter values of all analyzed beats can be viewed and statistically analyzed. An attractive feature of the HEART program is the ability to analyze data with visual quality assurance throughout the process, thus establishing a framework toward which Good Laboratory Practice (GLP) compliance can be obtained. Additionally, the development of HEART on the Matlab platform provides users with the flexibility to adapt or create study specific analysis files according to their specific needs. Copyright 2003 Elsevier Ltd.

  14. Increased Short-Term Beat-To-Beat Variability of QT Interval in Patients with Acromegaly

    Science.gov (United States)

    Orosz, Andrea; Csajbók, Éva; Czékus, Csilla; Gavallér, Henriette; Magony, Sándor; Valkusz, Zsuzsanna; Várkonyi, Tamás T.; Nemes, Attila; Baczkó, István; Forster, Tamás; Wittmann, Tibor; Papp, Julius Gy.; Varró, András; Lengyel, Csaba

    2015-01-01

    Cardiovascular diseases, including ventricular arrhythmias are responsible for increased mortality in patients with acromegaly. Acromegaly may cause repolarization abnormalities such as QT prolongation and impairment of repolarization reserve enhancing liability to arrhythmia. The aim of this study was to determine the short-term beat-to-beat QT variability in patients with acromegaly. Thirty acromegalic patients (23 women and 7 men, mean age±SD: 55.7±10.4 years) were compared with age- and sex-matched volunteers (mean age 51.3±7.6 years). Cardiac repolarization parameters including frequency corrected QT interval, PQ and QRS intervals, duration of terminal part of T waves (Tpeak-Tend) and short-term variability of QT interval were evaluated. All acromegalic patients and controls underwent transthoracic echocardiographic examination. Autonomic function was assessed by means of five standard cardiovascular reflex tests. Comparison of the two groups revealed no significant differences in the conventional ECG parameters of repolarization (QT: 401.1±30.6 ms vs 389.3±16.5 ms, corrected QT interval: 430.1±18.6 ms vs 425.6±17.3 ms, QT dispersion: 38.2±13.2 ms vs 36.6±10.2 ms; acromegaly vs control, respectively). However, short-term beat-to-beat QT variability was significantly increased in acromegalic patients (4.23±1.03 ms vs 3.02±0.80, Pacromegaly in spite of unchanged conventional parameters of ventricular repolarization. This enhanced temporal QT variability may be an early indicator of increased liability to arrhythmia. PMID:25915951

  15. Ciliary neurotrophic factor is an endogenous pyrogen.

    Science.gov (United States)

    Shapiro, L; Zhang, X X; Rupp, R G; Wolff, S M; Dinarello, C A

    1993-09-15

    Fever is initiated by the action of polypeptide cytokines called endogenous pyrogens, which are produced by the host during inflammation, trauma, or infection and which elevate the thermoregulatory set point in the hypothalamus. Ciliary neurotrophic factor (CNTF) supports the differentiation and survival of central and peripheral neurons. We describe the activity of CNTF as intrinsically pyrogenic in the rabbit. CNTF induced a monophasic fever which rose rapidly (within the first 12 min) following intravenous injection; CNTF fever was blocked by pretreatment with indomethacin. The fever induced by CNTF was not due to contaminating endotoxins. Increasing doses of CNTF resulted in prolongation of the fever, suggesting the subsequent induction of additional endogenous pyrogenic activity. After passive transfer of plasma obtained during CNTF-induced fever, endogenous pyrogen activity was not present in the circulation; CNTF also did not induce the endogenous pyrogens interleukin 1, tumor necrosis factor, or interleukin 6 in vitro. Nevertheless, a second endogenous pyrogen may originate within the central nervous system following the systemic injection of CNTF. Of the four endogenous pyrogens described to date (interleukin 1, tumor necrosis factor, interferon, and interleukin 6), CNTF, like interleukin 6, utilizes the cell-surface gp 130 signal-transduction apparatus.

  16. Average beta-beating from random errors

    CERN Document Server

    Tomas Garcia, Rogelio; Langner, Andy Sven; Malina, Lukas; Franchi, Andrea; CERN. Geneva. ATS Department

    2018-01-01

    The impact of random errors on average β-beating is studied via analytical derivations and simulations. A systematic positive β-beating is expected from random errors quadratic with the sources or, equivalently, with the rms β-beating. However, random errors do not have a systematic effect on the tune.

  17. CCDC103 mutations cause primary ciliary dyskinesia by disrupting assembly of ciliary dynein arms

    Science.gov (United States)

    Panizzi, Jennifer R.; Becker-Heck, Anita; Castleman, Victoria H.; Al-Mutairi, Dalal; Liu, Yan; Loges, Niki T.; Pathak, Narendra; Austin-Tse, Christina; Sheridan, Eamonn; Schmidts, Miriam; Olbrich, Heike; Werner, Claudius; Häffner, Karsten; Hellman, Nathan; Chodhari, Rahul; Gupta, Amar; Kramer-Zucker, Albrecht; Olale, Felix; Burdine, Rebecca D.; Schier, Alexander F.; O’Callaghan, Christopher; Chung, Eddie MK; Reinhardt, Richard; Mitchison, Hannah M.; King, Stephen M.; Omran, Heymut; Drummond, Iain A.

    2012-01-01

    Cilia are essential for fertilization, respiratory clearance, cerebrospinal fluid circulation, and to establish laterality1. Cilia motility defects cause Primary Ciliary Dyskinesia (PCD, MIM 242650), a disorder affecting 1:15-30,000 births. Cilia motility requires the assembly of multisubunit dynein arms that drive cilia bending2. Despite progress in understanding the genetic basis of PCD, mutations remain to be identified for several PCD linked loci3. Here we show that the zebrafish cilia paralysis mutant schmalhanstn222 (smh) mutant encodes the coiled-coil domain containing 103 protein (Ccdc103), a foxj1a regulated gene. Screening 146 unrelated PCD families identified patients in six families with reduced outer dynein arms, carrying mutations in CCDC103. Dynein arm assembly in smh mutant zebrafish was rescued by wild-type but not mutant human CCDC103. Chlamydomonas Ccdc103 functions as a tightly bound, axoneme-associated protein. The results identify Ccdc103 as a novel dynein arm attachment factor that when mutated causes Primary Ciliary Dyskinesia. PMID:22581229

  18. Auditory beat stimulation and its effects on cognition and mood States.

    Science.gov (United States)

    Chaieb, Leila; Wilpert, Elke Caroline; Reber, Thomas P; Fell, Juergen

    2015-01-01

    Auditory beat stimulation may be a promising new tool for the manipulation of cognitive processes and the modulation of mood states. Here, we aim to review the literature examining the most current applications of auditory beat stimulation and its targets. We give a brief overview of research on auditory steady-state responses and its relationship to auditory beat stimulation (ABS). We have summarized relevant studies investigating the neurophysiological changes related to ABS and how they impact upon the design of appropriate stimulation protocols. Focusing on binaural-beat stimulation, we then discuss the role of monaural- and binaural-beat frequencies in cognition and mood states, in addition to their efficacy in targeting disease symptoms. We aim to highlight important points concerning stimulation parameters and try to address why there are often contradictory findings with regard to the outcomes of ABS.

  19. Progressive hemifacial atrophy with ciliary body atrophy and ocular hypotony

    Directory of Open Access Journals (Sweden)

    T Ashwini Kini

    2015-01-01

    Full Text Available Progressive hemifacial atrophy (PHA is a disease of unknown etiology affecting one-half of the face. Ocular involvement is uncommon. Atrophy of iris is rare, with only a few cases of partial atrophy being reported in the literature. We report a case of total atrophy of iris and ciliary body with associated ocular hypotony in a 16-year-old girl with PHA. We believe this is the first reported case of complete atrophy of iris and ciliary body in PHA. Ocular hypotony in PHA was thought to be due to intra-ocular inflammation. However in our case it appears to be secondary to severe atrophy of the ciliary body.

  20. Clinical care of children with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Lucas, Jane S; Alanin, Mikkel Christian; Collins, Samuel

    2017-01-01

    INTRODUCTION: Primary ciliary dyskinesia (PCD) is a rare heterogeneous disorder, usually inherited as an autosomal recessive condition but X-linked inheritance is also described. Abnormal ciliary function in childhood leads to neonatal respiratory distress in term infants, persistent wet cough...... is inappropriate since differences in pathophysiology, morbidity and prognosis risk treatment failure and lack of adherence. Areas covered: Review authors searched PubMed and Cochrane databases for publications relating to management of children with PCD. Because of the paucity of data, we emphasise the need...

  1. Mechanisms of Wing Beat Sound in Flapping Wings of Beetles

    Science.gov (United States)

    Allen, John

    2017-11-01

    While the aerodynamic aspects of insect flight have received recent attention, the mechanisms of sound production by flapping wings is not well understood. Though the harmonic structure of wing beat frequency modulation has been reported with respect to biological implications, few studies have rigorously quantified it with respect directionality, phase coupling and vortex tip scattering. Moreover, the acoustic detection and classification of invasive species is both of practical as well scientific interest. In this study, the acoustics of the tethered flight of the Coconut Rhinoceros Beetle (Oryctes rhinoceros) is investigated with four element microphone array in conjunction with complementary optical sensors and high speed video. The different experimental methods for wing beat determination are compared in both the time and frequency domain. Flow visualization is used to examine the vortex and sound generation due to the torsional mode of the wing rotation. Results are compared with related experimental studies of the Oriental Flower Beetle. USDA, State of Hawaii.

  2. Analysis of fluid flow around a beating artificial cilium

    Directory of Open Access Journals (Sweden)

    Mojca Vilfan

    2012-02-01

    Full Text Available Biological cilia are found on surfaces of some microorganisms and on surfaces of many eukaryotic cells where they interact with the surrounding fluid. The periodic beating of the cilia is asymmetric, resulting in directed swimming of unicellular organisms or in generation of a fluid flow above a ciliated surface in multicellular ones. Following the biological example, externally driven artificial cilia have recently been successfully implemented as micropumps and mixers. However, biomimetic systems are useful not only in microfluidic applications, but can also serve as model systems for the study of fundamental hydrodynamic phenomena in biological samples. To gain insight into the basic principles governing propulsion and fluid pumping on a micron level, we investigated hydrodynamics around one beating artificial cilium. The cilium was composed of superparamagnetic particles and driven along a tilted cone by a varying external magnetic field. Nonmagnetic tracer particles were used for monitoring the fluid flow generated by the cilium. The average flow velocity in the pumping direction was obtained as a function of different parameters, such as the rotation frequency, the asymmetry of the beat pattern, and the cilium length. We also calculated the velocity field around the beating cilium by using the analytical far-field expansion. The measured average flow velocity and the theoretical prediction show an excellent agreement.

  3. A high-density EEG investigation into steady state binaural beat stimulation.

    Directory of Open Access Journals (Sweden)

    Peter Goodin

    Full Text Available Binaural beats are an auditory phenomenon that has been suggested to alter physiological and cognitive processes including vigilance and brainwave entrainment. Some personality traits measured by the NEO Five Factor Model have been found to alter entrainment using pulsing light stimuli, but as yet no studies have examined if this occurs using steady state presentation of binaural beats for a relatively short presentation of two minutes. This study aimed to examine if binaural beat stimulation altered vigilance or cortical frequencies and if personality traits were involved. Thirty-one participants were played binaural beat stimuli designed to elicit a response at either the Theta (7 Hz or Beta (16 Hz frequency bands while undertaking a zero-back vigilance task. EEG was recorded from a high-density electrode cap. No significant differences were found in vigilance or cortical frequency power during binaural beat stimulation compared to a white noise control period. Furthermore, no significant relationships were detected between the above and the Big Five personality traits. This suggests a short presentation of steady state binaural beats are not sufficient to alter vigilance or entrain cortical frequencies at the two bands examined and that certain personality traits were not more susceptible than others.

  4. A high-density EEG investigation into steady state binaural beat stimulation.

    Science.gov (United States)

    Goodin, Peter; Ciorciari, Joseph; Baker, Kate; Carey, Anne-Marie; Carrey, Anne-Marie; Harper, Michelle; Kaufman, Jordy

    2012-01-01

    Binaural beats are an auditory phenomenon that has been suggested to alter physiological and cognitive processes including vigilance and brainwave entrainment. Some personality traits measured by the NEO Five Factor Model have been found to alter entrainment using pulsing light stimuli, but as yet no studies have examined if this occurs using steady state presentation of binaural beats for a relatively short presentation of two minutes. This study aimed to examine if binaural beat stimulation altered vigilance or cortical frequencies and if personality traits were involved. Thirty-one participants were played binaural beat stimuli designed to elicit a response at either the Theta (7 Hz) or Beta (16 Hz) frequency bands while undertaking a zero-back vigilance task. EEG was recorded from a high-density electrode cap. No significant differences were found in vigilance or cortical frequency power during binaural beat stimulation compared to a white noise control period. Furthermore, no significant relationships were detected between the above and the Big Five personality traits. This suggests a short presentation of steady state binaural beats are not sufficient to alter vigilance or entrain cortical frequencies at the two bands examined and that certain personality traits were not more susceptible than others.

  5. Measuring of beat up force on weaving machines

    Directory of Open Access Journals (Sweden)

    Bílek Martin

    2017-01-01

    Full Text Available The textile material (warp is stressed cyclically at a relative high frequency during the weaving process. Therefore, the special measuring device for analysis of beat up force in the textile material during the weaving process, has been devised in the Weaving Laboratory of the TUL. This paper includes a description of this measuring device. The experimental part includes measurements results for various materials (PES and VS and various warp thread densities of the produced fabric.

  6. Binaural beat technology in humans: a pilot study to assess neuropsychologic, physiologic, and electroencephalographic effects.

    Science.gov (United States)

    Wahbeh, Helané; Calabrese, Carlo; Zwickey, Heather; Zajdel, Dan

    2007-03-01

    When two auditory stimuli of different frequency are presented to each ear, binaural beats are perceived by the listener. The binaural beat frequency is equal to the difference between the frequencies applied to each ear. Our primary objective was to assess whether steady-state entrainment of electroencephalographic activity to the binaural beat occurs when exposed to a specific binaural beat frequency as has been hypothesized. Our secondary objective was to gather preliminary data on neuropsychologic and physiologic effects of binaural beat technology. A randomized, blinded, placebo-controlled crossover experiment in 4 healthy adult subjects. Subjects were randomized to experimental auditory stimulus of 30 minutes of binaural beat at 7 Hz (carrier frequencies: 133 Hz L; 140 Hz R) with an overlay of pink noise resembling the sound of rain on one session and control stimuli of the same overlay without the binaural beat carrier frequencies on the other session. Data were collected during two separate sessions 1 week apart. Neuropsychologic and blood pressure data were collected before and after the intervention; electroencephalographic data were collected before, during, and after listening to either binaural beats or control. Neuropsychologic measures included State Trait Anxiety Inventory, Profile of Mood States, Rey Auditory Verbal List Test, Stroop Test, and Controlled Oral Word Association Test. Spectral and coherence analysis was performed on the electroencephalogram (EEG), and all measures were analyzed for changes between sessions with and without binaural beat stimuli. There were no significant differences between the experimental and control conditions in any of the EEG measures. There was an increase of the Profile of Mood States depression subscale in the experimental condition relative to the control condition (p = 0.02). There was also a significant decrease in immediate verbal memory recall (p = 0.03) in the experimental condition compared to control

  7. Long-term outcome of Tunisian children with primary ciliary ...

    African Journals Online (AJOL)

    Objective: To study the long-term outcome of PCD in Tunisian children with ciliary ultra-structure defects detected by electron .... The middle lobe was as much affected as the right up- .... distress syndrome (ARDS) after one and four years of.

  8. Effect of air pollutants on ciliary activity of respiratory tract

    Energy Technology Data Exchange (ETDEWEB)

    Omachi, S; Kita, H

    1974-12-01

    The effect of sulfur dioxide, nitrogen dioxide, nitric oxide, ozone, and formaldehyde on the ciliary activity of an excised specimen of the trachea of a guinea pig was investigated. The influence of these gases is determined by the Half Reduction Time of the ciliary activity, which is the time lapse from the beginning of the gas exposure at a certain concentration to the point of which the activity is reduced by half. The Half Reduction Time of the ciliary activity by each gas at the concentration of 50 ppM is SO/sub 2/, 4 min; HCHO, 5 min; NO/sub 2/, 10 min; NO, 14 min; and O/sub 3/, 20 min. The influence of the easily water soluble gases such as SO/sub 2/ and HCHO on the ciliary activity is severe compared with the less water soluble ones, NO/sub 2/ and O/sub 3/, which pass over the mucous surface of the upper airway without dissolving to the mucous layer.

  9. Multicavitary ciliary body melanoma presenting as a cyst

    Directory of Open Access Journals (Sweden)

    Jennifer Jang

    2013-01-01

    Full Text Available Cyst-like cavities in uveal melanoma occur rarely and can simulate a benign intraocular cystic lesion resulting in delayed diagnosis and inappropriate management. Herein, we describe a 66-year-old Caucasian female who presented with a "cystic" ciliary body mass in the right eye oculus dexter (OD. Slit lamp examination OD showed anterior bulging of the iris temporally from an underlying pigmented ciliary body mass and transillumination disclosed slight shadow from the tumor. Ultrasound biomicroscopy (UBM revealed multiple cyst-like cavities within a tumor, lined by "thick walls" of at least 200 μm and occupying 80% of the tumor volume. A clinical diagnosis of multi-cavitary ciliary body melanoma was suspected and partial lamellar sclero iridocyclectomy was performed. Histopathology confirmed the diagnosis of low-grade spindle melanoma of the ciliary body with multiple empty and fluid filled cyst-like cavities without epithelial lining. UBM is an important diagnostic tool in the differentiation of "thick walled" cavitary melanoma from "thin walled" benign pigment epithelial cyst.

  10. More attentional focusing through binaural beats: Evidence from the global-local task

    OpenAIRE

    Colzato, L.S.; Barone, H.; Sellaro, R.; Hommel, B.

    2017-01-01

    A recent study showed that binaural beats have an impact on the efficiency of allocating attention over time. We were interested to see whether this impact affects attentional focusing or, even further, the top-down control over irrelevant information. Healthy adults listened to gamma-frequency (40?Hz) binaural beats, which are assumed to increase attentional concentration, or a constant tone of 340?Hz (control condition) for 3?min before and during a global?local task. While the size of the ...

  11. Orthogonal linear polarization tunable-beat ring laser with a superluminescent diode

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Y.; Yoshino, T. [Department of Electronic Engineering, Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376 (Japan)

    1997-09-01

    An orthogonal linear polarization operated ring laser with a superluminescent diode has been demonstrated to generate a tunable optical beat signal. The ring cavity contains a superluminescent diode as the optical gain medium, Faraday rotators, and a variable phase retarder (Babinet-Soleil compensator). By controlling the retarder, we changed the beat frequency in the range from a few tens of megahertz to 100 MHz. {copyright} 1997 Optical Society of America

  12. Electrical brain responses to beat irregularities in two cases of beat deafness

    NARCIS (Netherlands)

    Mathias, B.; Lidji, P.; Honing, H.; Palmer, C.; Peretz, I.

    2016-01-01

    Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to

  13. Human cortical responses to slow and fast binaural beats reveal multiple mechanisms of binaural hearing.

    Science.gov (United States)

    Ross, Bernhard; Miyazaki, Takahiro; Thompson, Jessica; Jamali, Shahab; Fujioka, Takako

    2014-10-15

    When two tones with slightly different frequencies are presented to both ears, they interact in the central auditory system and induce the sensation of a beating sound. At low difference frequencies, we perceive a single sound, which is moving across the head between the left and right ears. The percept changes to loudness fluctuation, roughness, and pitch with increasing beat rate. To examine the neural representations underlying these different perceptions, we recorded neuromagnetic cortical responses while participants listened to binaural beats at a continuously varying rate between 3 Hz and 60 Hz. Binaural beat responses were analyzed as neuromagnetic oscillations following the trajectory of the stimulus rate. Responses were largest in the 40-Hz gamma range and at low frequencies. Binaural beat responses at 3 Hz showed opposite polarity in the left and right auditory cortices. We suggest that this difference in polarity reflects the opponent neural population code for representing sound location. Binaural beats at any rate induced gamma oscillations. However, the responses were largest at 40-Hz stimulation. We propose that the neuromagnetic gamma oscillations reflect postsynaptic modulation that allows for precise timing of cortical neural firing. Systematic phase differences between bilateral responses suggest that separate sound representations of a sound object exist in the left and right auditory cortices. We conclude that binaural processing at the cortical level occurs with the same temporal acuity as monaural processing whereas the identification of sound location requires further interpretation and is limited by the rate of object representations. Copyright © 2014 the American Physiological Society.

  14. Speed of light demonstration using Doppler beat

    Science.gov (United States)

    Bernal, Luis; Bilbao, Luis

    2018-05-01

    From an apparatus previously designed for measuring the Doppler shift using a rotating mirror, an improved, versatile version was developed for speed of light demonstrations in a classroom or a teaching laboratory. By adding a second detector and adequate beam-splitter and mirrors, three different configurations are easily assembled. One configuration is used for time-of-flight measurements between a near and a far detector, allowing one to measure the speed of light provided that the path length between detectors is known. Another variation is the interferometric method obtained by superposing the far and near signals in such a way that a minimum of the combined signal is obtained when the time delay makes the signals arrive out of phase by π radians. Finally, the standard Doppler configuration allows the measurement of the frequency beat as a function of the rotation frequency. The main advantages of the apparatus are (a) the experimental setup is simple and completely accessible to undergraduate students, (b) the light is visible, students can see the rays, which, with the use of appropriate screens, can be blocked at any point along their paths, (c) the experiment can take place entirely within the teaching laboratory or demonstration room (using the interferometric method, the shortest distance to the far mirror was as small as 0.5 m), and (d) different configurations can be built, including some economical setups within the budget of teaching laboratories.

  15. The Simplest Demonstration on Acoustic Beats

    Science.gov (United States)

    Ganci, Alessio; Ganci, Salvatore

    2015-01-01

    The classical demonstration experiment on acoustic beats using two signal generators and a dual trace oscilloscope is an important ingredient in teaching the subject. This short laboratory note aims to point out what may be the simplest demonstrative experiment on acoustic beats to carry out in a classroom without employing any lab apparatus.

  16. Mismatch negativity to acoustical illusion of beat: how and where the change detection takes place?

    Science.gov (United States)

    Chakalov, Ivan; Paraskevopoulos, Evangelos; Wollbrink, Andreas; Pantev, Christo

    2014-10-15

    In case of binaural presentation of two tones with slightly different frequencies the structures of brainstem can no longer follow the interaural time differences (ITD) resulting in an illusionary perception of beat corresponding to frequency difference between the two prime tones. Hence, the beat-frequency does not exist in the prime tones presented to either ear. This study used binaural beats to explore the nature of acoustic deviance detection in humans by means of magnetoencephalography (MEG). Recent research suggests that the auditory change detection is a multistage process. To test this, we employed 26 Hz-binaural beats in a classical oddball paradigm. However, the prime tones (250 Hz and 276 Hz) were switched between the ears in the case of the deviant-beat. Consequently, when the deviant is presented, the cochleae and auditory nerves receive a "new afferent", although the standards and the deviants are heard identical (26 Hz-beats). This allowed us to explore the contribution of auditory periphery to change detection process, and furthermore, to evaluate its influence on beats-related auditory steady-state responses (ASSRs). LORETA-source current density estimates of the evoked fields in a typical mismatch negativity time-window (MMN) and the subsequent difference-ASSRs were determined and compared. The results revealed an MMN generated by a complex neural network including the right parietal lobe and the left middle frontal gyrus. Furthermore, difference-ASSR was generated in the paracentral gyrus. Additionally, psychophysical measures showed no perceptual difference between the standard- and deviant-beats when isolated by noise. These results suggest that the auditory periphery has an important contribution to novelty detection already at sub-cortical level. Overall, the present findings support the notion of hierarchically organized acoustic novelty detection system. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Feeling the beat: premotor and striatal interactions in musicians and non-musicians during beat perception

    Science.gov (United States)

    Grahn, Jessica A.; Rowe, James B.

    2009-01-01

    Little is known about the underlying neurobiology of rhythm and beat perception, despite its universal cultural importance. Here we used functional magnetic resonance imaging to study rhythm perception in musicians and non-musicians. Three conditions varied in the degree to which external reinforcement versus internal generation of the beat was required. The ‘Volume’ condition strongly externally marked the beat with volume changes, the ‘Duration’ condition marked the beat with weaker accents arising from duration changes, and the ‘Unaccented’ condition required the beat to be entirely internally generated. In all conditions, beat rhythms compared to nonbeat control rhythms revealed putamen activity. The presence of a beat was also associated with greater connectivity between the putamen and the supplementary motor area (SMA), the premotor cortex (PMC) and auditory cortex. In contrast, the type of accent within the beat conditions modulated the coupling between premotor and auditory cortex, with greater modulation for musicians than non-musicians. Importantly, the putamen's response to beat conditions was not due to differences in temporal complexity between the three rhythm conditions. We propose that a cortico-subcortical network including the putamen, SMA, and PMC is engaged for the analysis of temporal sequences and prediction or generation of putative beats, especially under conditions that may require internal generation of the beat. The importance of this system for auditory-motor interaction and development of precisely timed movement is suggested here by its facilitation in musicians. PMID:19515922

  18. Tracking EEG changes in response to alpha and beta binaural beats.

    Science.gov (United States)

    Vernon, D; Peryer, G; Louch, J; Shaw, M

    2014-07-01

    A binaural beat can be produced by presenting two tones of a differing frequency, one to each ear. Such auditory stimulation has been suggested to influence behaviour and cognition via the process of cortical entrainment. However, research so far has only shown the frequency following responses in the traditional EEG frequency ranges of delta, theta and gamma. Hence a primary aim of this research was to ascertain whether it would be possible to produce clear changes in the EEG in either the alpha or beta frequency ranges. Such changes, if possible, would have a number of important implications as well as potential applications. A secondary goal was to track any observable changes in the EEG throughout the entrainment epoch to gain some insight into the nature of the entrainment effects on any changes in an effort to identify more effective entrainment regimes. Twenty two healthy participants were recruited and randomly allocated to one of two groups, each of which was exposed to a distinct binaural beat frequency for ten 1-minute epochs. The first group listened to an alpha binaural beat of 10 Hz and the second to a beta binaural beat of 20 Hz. EEG was recorded from the left and right temporal regions during pre-exposure baselines, stimulus exposure epochs and post-exposure baselines. Analysis of changes in broad-band and narrow-band amplitudes, and frequency showed no effect of binaural beat frequency eliciting a frequency following effect in the EEG. Possible mediating factors are discussed and a number of recommendations are made regarding future studies, exploring entrainment effects from a binaural beat presentation. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Frequency of exercise-induced ST-T-segment deviations and cardiac arrhythmias in recreational endurance athletes during a marathon race: results of the prospective observational Berlin Beat of Running study.

    Science.gov (United States)

    Herm, Juliane; Töpper, Agnieszka; Wutzler, Alexander; Kunze, Claudia; Krüll, Matthias; Brechtel, Lars; Lock, Jürgen; Fiebach, Jochen B; Heuschmann, Peter U; Haverkamp, Wilhelm; Endres, Matthias; Jungehulsing, Gerhard Jan; Haeusler, Karl Georg

    2017-08-03

    While regular physical exercise has many health benefits, strenuous physical exercise may have a negative impact on cardiac function. The 'Berlin Beat of Running' study focused on feasibility and diagnostic value of continuous ECG monitoring in recreational endurance athletes during a marathon race. We hypothesised that cardiac arrhythmias and especially atrial fibrillation are frequently found in a cohort of recreational endurance athletes. The main secondary hypothesis was that pathological laboratory findings in these athletes are (in part) associated with cardiac arrhythmias. Prospective observational cohort study including healthy volunteers. One hundred and nine experienced marathon runners wore a portable ECG recorder during a marathon race in Berlin, Germany. Athletes underwent blood tests 2-3 days prior, directly after and 1-2 days after the race. Overall, 108 athletes (median 48 years (IQR 45-53), 24% women) completed the marathon in 249±43 min. Blinded ECG analysis revealed abnormal findings during the marathon in 18 (16.8%) athletes. Ten (9.3%) athletes had at least one episode of non-sustained ventricular tachycardia, one of whom had atrial fibrillation; eight (7.5%) individuals showed transient ST-T-segment deviations. Abnormal ECG findings were associated with advanced age (OR 1.11 per year, 95% CI 1.01 to 1.23), while sex and cardiovascular risk profile had no impact. Directly after the race, high-sensitive troponin T was elevated in 18 (16.7%) athletes and associated with ST-T-segment deviation (OR 9.9, 95% CI 1.9 to 51.5), while age, sex and cardiovascular risk profile had no impact. ECG monitoring during a marathon is feasible. Abnormal ECG findings were present in every sixth athlete. Exercise-induced transient ST-T-segment deviations were associated with elevated high-sensitive troponin T (hsTnT) values. ClinicalTrials.gov NCT01428778; Results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article

  20. The role of nonlinear beating currents on parametric instabilities in magnetoplasmas

    International Nuclear Information System (INIS)

    Kuo, S.P.

    1996-01-01

    A general coupled mode equation for the low-frequency decay modes of parametric instabilities in magnetoplasmas is derived. The relative importance of the nonlinear contributions from the ponderomotive force, nonlinear beating current, and anisotropic effect to the parametric coupling is then manifested by the coupling terms of the equation. It is first shown in the unmagnetized case, that the contribution of the nonlinear beating current is negligibly small because of the small coefficient (i.e., weight) of this current contribution, instead of the beating current itself. It then follows that the weight of the beating current contribution increases significantly in the magnetized case, and consequently, this contribution to the parametric coupling is found to be important, as exemplified by two specific examples. copyright 1996 American Institute of Physics

  1. Intraflagellar Transport (IFT) Role in Ciliary Assembly, Resorption and Signalling

    DEFF Research Database (Denmark)

    Pedersen, Lotte B; Rosenbaum, Joel L

    2008-01-01

    Cilia and flagella have attracted tremendous attention in recent years as research demonstrated crucial roles for these organelles in coordinating a number of physiologically and developmentally important signaling pathways, including the platelet-derived growth factor receptor (PDGFR) alpha, Sonic...... hedgehog, polycystin, and Wnt pathways. In addition, the realization that defective assembly or function of cilia can cause a plethora of diseases and developmental defects ("ciliopathies") has increased focus on the mechanisms by which these antenna-like, microtubular structures assemble. Ciliogenesis...... mechanisms and functions of IFT. In addition to a general, up-to-date description of IFT, we discuss mechanisms by which proteins are selectively targeted to the ciliary compartment, with special focus on the ciliary transition zone. Finally, we briefly review the role of IFT in cilia-mediated signaling...

  2. Direct Visualization of Mechanical Beats by Means of an Oscillating Smartphone

    Science.gov (United States)

    Giménez, Marcos H.; Salinas, Isabel; Monsoriu, Juan A.; Castro-Palacio, Juan C.

    2017-01-01

    The resonance phenomenon is widely known in physics courses. Qualitatively speaking, resonance takes place in a driven oscillating system whenever the frequency approaches the natural frequency, resulting in maximal oscillatory amplitude. Very closely related to resonance is the phenomenon of mechanical beating, which occurs when the driving and…

  3. Auditory evoked responses to binaural beat illusion: stimulus generation and the derivation of the Binaural Interaction Component (BIC).

    Science.gov (United States)

    Ozdamar, Ozcan; Bohorquez, Jorge; Mihajloski, Todor; Yavuz, Erdem; Lachowska, Magdalena

    2011-01-01

    Electrophysiological indices of auditory binaural beats illusions are studied using late latency evoked responses. Binaural beats are generated by continuous monaural FM tones with slightly different ascending and descending frequencies lasting about 25 ms presented at 1 sec intervals. Frequency changes are carefully adjusted to avoid any creation of abrupt waveform changes. Binaural Interaction Component (BIC) analysis is used to separate the neural responses due to binaural involvement. The results show that the transient auditory evoked responses can be obtained from the auditory illusion of binaural beats.

  4. Melanocytoma of the ciliary body misdiagnosed as iridodialysis

    Directory of Open Access Journals (Sweden)

    Kim M

    2014-05-01

    Full Text Available Moosang Kim, Seung-Jun LeeDepartment of Ophthalmology, School of Medicine, Kangwon National University, Chuncheon, Republic of KoreaAbstract: A 62-year-old female presented to our institution with dimness of vision in her right eye. On examination, her best corrected visual acuity was 20/100 in the right eye. The intraocular pressures were 14 mmHg in both eyes. Slit-lamp examination revealed nuclear sclerotic cataracts bilaterally and iridodialysis in her right eye. Seven days after the first visit, cataract surgery was performed without any complications. One year later, she presented to our institution with acute visual loss and ocular pain in the right eye. Best corrected visual acuity of the right eye was light perception and the intraocular pressure was 44 mmHg. Slit-lamp examination revealed a ciliary body mass with widespread pigment dispersion in the anterior segment. Due to no useful vision and uncontrolled pain, enucleation of the right eye was performed. Histopathologic examination revealed a melanocytoma of the ciliary body.Keywords: ciliary body, iridodialysis, melanocytoma

  5. Electrical Brain Responses to Beat Irregularities in Two Cases of Beat Deafness

    Science.gov (United States)

    Mathias, Brian; Lidji, Pascale; Honing, Henkjan; Palmer, Caroline; Peretz, Isabelle

    2016-01-01

    Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to move along with a beat. Studies on the neural underpinnings of beat processing in the general population suggest that the auditory system is capable of pre-attentively generating a predictive model of upcoming sounds in a rhythmic pattern, subserved largely within auditory cortex and reflected in mismatch negativity (MMN) and P3 event-related potential (ERP) components. The current study examined these neural correlates of beat perception in two beat-deaf individuals, Mathieu and Marjorie, and a group of control participants under conditions in which auditory stimuli were either attended or ignored. Compared to control participants, Mathieu demonstrated reduced behavioral sensitivity to beat omissions in metrical patterns, and Marjorie showed a bias to identify irregular patterns as regular. ERP responses to beat omissions reveal an intact pre-attentive system for processing beat irregularities in cases of beat deafness, reflected in the MMN component, and provide partial support for abnormalities in later cognitive stages of beat processing, reflected in an unreliable P3b component exhibited by Mathieu—but not Marjorie—compared to control participants. P3 abnormalities observed in the current study resemble P3 abnormalities exhibited by individuals with pitch-based amusia, and are consistent with attention or auditory-motor coupling accounts of deficits in beat perception. PMID:26941591

  6. Electrical brain responses to beat irregularities in two cases of beat deafness

    Directory of Open Access Journals (Sweden)

    Brian eMathias

    2016-02-01

    Full Text Available Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to move along with a beat. Studies on the neural underpinnings of beat processing in the general population suggest that the auditory system is capable of pre-attentively generating a predictive model of upcoming sounds in a rhythmic pattern, subserved largely within auditory cortex and reflected in mismatch negativity (MMN and P3 event-related potential (ERP components. The current study examined these neural correlates of beat perception in two beat-deaf individuals, Mathieu and Marjorie, and a group of control participants under conditions in which auditory stimuli were either attended or ignored. Compared to control participants, Mathieu demonstrated reduced behavioral sensitivity to beat omissions in metrical patterns, and Marjorie showed a bias to identify irregular patterns as regular. ERP responses to beat omissions reveal an intact pre-attentive system for processing beat irregularities in cases of beat deafness, reflected in the MMN component, and provide partial support for abnormalities in later cognitive stages of beat processing, reflected in an unreliable P3b component exhibited by Mathieu – but not Marjorie – compared to control participants. P3 abnormalities observed in the current study resemble P3 abnormalities exhibited by individuals with pitch-based amusia, and are consistent with attention or auditory-motor coupling accounts of deficits in beat perception.

  7. Binaural beat technology in humans: a pilot study to assess psychologic and physiologic effects.

    Science.gov (United States)

    Wahbeh, Helané; Calabrese, Carlo; Zwickey, Heather

    2007-01-01

    Binaural beat technology (BBT) products are sold internationally as personal development and health improvement tools. Producers suggest benefit from regular listening to binaural beats including reduced stress and anxiety, and increased focus, concentration, motivation, confidence, and depth in meditation. Binaural beats are auditory brainstem responses that originate in the superior olivary nucleus as a result of different frequency auditory stimuli provided to each ear. Listeners to binaural beat "hear" a beat at a frequency equal to the difference between the frequencies of the applied tones. The objectives of this pilot study were to gather preliminary data on psychologic and physiologic effects of 60 days daily use of BBT for hypothesis generation and to assess compliance, feasibility, and safety for future studies. Uncontrolled pilot study. Eight healthy adults participated in the study. Participants listened to a CD with delta (0-4 Hz) binaural beat frequencies daily for 60 days. Psychologic and physiological data were collected before and after a 60-day intervention. PSYCHOLOGIC: Depression (Beck Depression Inventory-2), anxiety (State-Trait Anxiety Inventory), mood (Profile of Mood States), absorption (Tellegen Absorption Scale) and quality of Life (World Health Organization-Quality of Life Inventory). PHYSIOLOGICAL: Cortisol, dehydroepiandrosterone, melatonin, insulin-like growth factor-1, serotonin, dopamine, epinephrine, norepinephrine, weight, blood pressure, high sensitivity C-reactive protein. There was a decrease in trait anxiety (p = 0.004), an increase in quality of life (p = 0.03), and a decrease in insulin-like growth factor-1 (p = 0.01) and dopamine (p = 0.02) observed between pre- and postintervention measurements. Binaural beat technology may exhibit positive effect on self-reported psychologic measures, especially anxiety. Further research is warranted to explore the effects on anxiety using a larger, randomized and controlled trial.

  8. Recent results on the beat wave acceleration of externally injected electrons on a plasma

    International Nuclear Information System (INIS)

    Clayton, C.E.; Marsh, K.; Dyson, A.; Everett, M.; Lal, A.; Josh, C.; Williams, R.; Katsouleas, T.

    1992-01-01

    In the Plasma Beat Wave Accelerator (PBWA) two laser beams of slightly different frequencies resonantly beat in a plasma in such a way that their frequency and wavenumber differences correspond to the plasma wave frequency and wavenumber. The amplitude-modulated electromagnetic wave envelope of the laser pulse exerts a periodic nonlinear force on the plasma electrons, causing them to bunch. The resulting space-charge wave can have a phase velocity nearly equal to the speed of light. If an electron bunch is injected with a velocity close to this it can be trapped and accelerated. The UCLA program investigating PBWA has found that tunnel or multi-photon ionized plasmas a re homogeneous enough for coherent macroscopic acceleration. The laser pulse should be short, and the peak laser intensity should be such that Iλ 2 ∼ 2 x 10 16 W/cm 2 μm 2 in order to get substantial beat wave amplitudes. tab., 3 refs

  9. Beating motion of a circular cylinder in vortex-induced vibrations

    Science.gov (United States)

    Shen, Linwei; Chan, Eng-Soon; Wei, Yan

    2018-04-01

    In this paper, beating phenomenon of a circular cylinder in vortex-induced vibration is studied by numerical simulations in a systematic manner. The cylinder mass coefficients of 2 and 10 are considered, and the Reynolds number is 150. Two distinctive frequencies, namely cylinder oscillation and vortex shedding frequencies, are obtained from the harmonic analysis of the cylinder displacement. The result is consistent with that observed in laboratory experiments. It is found that the cylinder oscillation frequency changes with the natural frequency of the cylinder while the reduced velocity is varied. The added-mass coefficient of the cylinder in beating motion is therefore estimated. Meanwhile, the vortex shedding frequency does not change dramatically in the beating situations. In fact, it is very close to 0.2. Accordingly, the lift force coefficient has two main components associated with these two frequencies. Besides, higher harmonics of the cylinder oscillation frequency appear in the spectrum of the lift coefficient. Moreover, the vortex shedding timing is studied in the beating motion by examining the instantaneous flow fields in the wake, and two scenarios of the vortex formation are observed.

  10. Effectiveness of binaural beats in reducing preoperative dental anxiety.

    Science.gov (United States)

    Isik, B K; Esen, A; Büyükerkmen, B; Kilinç, A; Menziletoglu, D

    2017-07-01

    Binaural beats are an auditory illusion perceived when two different pure-tone sine waves are presented one to each ear at a steady intensity and frequency. We evaluated their effectiveness in reducing preoperative anxiety in dentistry. Sixty patients (30 in each group) who were to have impacted third molars removed were studied (experimental group: 20 women and 10 men, mean (range) age 24 (18-35) years, and control group: 22 women and 8 men, mean (range) age 28 (15-47) years). All patients were fully informed about the operation preoperatively, and their anxiety recorded on a visual analogue scale (VAS). The local anaesthetic was given and the patients waited for 10minutes, during which those in the experimental group were asked to listen to binaural beats through stereo earphones (200Hz for the left ear and 209.3Hz for the right ear). No special treatment was given to the control group. In both groups anxiety was then recorded again, and the tooth removed in the usual way. The paired t test and t test were used to assess the significance of differences between groups. The degree of anxiety in the control group was unchanged after the second measurement (p=0.625), while that in the experimental group showed a significant reduction in anxiety (p=0.001). We conclude that binaural beats may be useful in reducing preoperative anxiety in dentistry. Copyright © 2017 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  11. Brain Responses to a 6-Hz Binaural Beat: Effects on General Theta Rhythm and Frontal Midline Theta Activity.

    Science.gov (United States)

    Jirakittayakorn, Nantawachara; Wongsawat, Yodchanan

    2017-01-01

    A binaural beat is a beat phenomenon that is generated by the dichotic presentation of two almost equivalent pure tones but with slightly different frequencies. The brain responses to binaural beats remain controversial; therefore, the aim of this study was to investigate theta activity responses to a binaural beat by controlling factors affecting localization, including beat frequency, carrier tone frequency, exposure duration, and recording procedure. Exposure to a 6-Hz binaural beat on a 250 Hz carrier tone for 30 min was utilized in this study. Quantitative electroencephalography (QEEG) was utilized as the recording modality. Twenty-eight participants were divided into experimental and control groups. Emotional states were evaluated by Brunel Mood Scale (BRMUS) before and after exposing to the stimulus. The results showed that theta activity was induced in the entire cortex within 10 min of exposure to the stimulus in the experimental group. Compared to the control group, theta activity was also induced at the frontal and parietal-central regions, which included the Fz position, and left hemisphere dominance was presented for other exposure durations. The pattern recorded for 10 min of exposure appeared to be brain functions of a meditative state. Moreover, tension factor of BRUMS was decreased in experimental group compared to control group which resembled the meditation effect. Thus, a 6-Hz binaural beat on a 250 Hz carrier tone was suggested as a stimulus for inducing a meditative state.

  12. Brain Responses to a 6-Hz Binaural Beat: Effects on General Theta Rhythm and Frontal Midline Theta Activity

    Directory of Open Access Journals (Sweden)

    Nantawachara Jirakittayakorn

    2017-06-01

    Full Text Available A binaural beat is a beat phenomenon that is generated by the dichotic presentation of two almost equivalent pure tones but with slightly different frequencies. The brain responses to binaural beats remain controversial; therefore, the aim of this study was to investigate theta activity responses to a binaural beat by controlling factors affecting localization, including beat frequency, carrier tone frequency, exposure duration, and recording procedure. Exposure to a 6-Hz binaural beat on a 250 Hz carrier tone for 30 min was utilized in this study. Quantitative electroencephalography (QEEG was utilized as the recording modality. Twenty-eight participants were divided into experimental and control groups. Emotional states were evaluated by Brunel Mood Scale (BRMUS before and after exposing to the stimulus. The results showed that theta activity was induced in the entire cortex within 10 min of exposure to the stimulus in the experimental group. Compared to the control group, theta activity was also induced at the frontal and parietal-central regions, which included the Fz position, and left hemisphere dominance was presented for other exposure durations. The pattern recorded for 10 min of exposure appeared to be brain functions of a meditative state. Moreover, tension factor of BRUMS was decreased in experimental group compared to control group which resembled the meditation effect. Thus, a 6-Hz binaural beat on a 250 Hz carrier tone was suggested as a stimulus for inducing a meditative state.

  13. Beating Depression …Help Is Available

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues Beating Depression …Help Is Available Past Issues / Summer 2007 Table ... treatments are available from your physician. Types of Depression Just like other illnesses, such as heart disease, ...

  14. The effect of gamma-enhancing binaural beats on the control of feature bindings.

    Science.gov (United States)

    Colzato, Lorenza S; Steenbergen, Laura; Sellaro, Roberta

    2017-07-01

    Binaural beats represent the auditory experience of an oscillating sound that occurs when two sounds with neighboring frequencies are presented to one's left and right ear separately. Binaural beats have been shown to impact information processing via their putative role in increasing neural synchronization. Recent studies of feature-repetition effects demonstrated interactions between perceptual features and action-related features: repeating only some, but not all features of a perception-action episode hinders performance. These partial-repetition (or binding) costs point to the existence of temporary episodic bindings (event files) that are automatically retrieved by repeating at least one of their features. Given that neural synchronization in the gamma band has been associated with visual feature bindings, we investigated whether the impact of binaural beats extends to the top-down control of feature bindings. Healthy adults listened to gamma-frequency (40 Hz) binaural beats or to a constant tone of 340 Hz (control condition) for ten minutes before and during a feature-repetition task. While the size of visuomotor binding costs (indicating the binding of visual and action features) was unaffected by the binaural beats, the size of visual feature binding costs (which refer to the binding between the two visual features) was considerably smaller during gamma-frequency binaural beats exposure than during the control condition. Our results suggest that binaural beats enhance selectivity in updating episodic memory traces and further strengthen the hypothesis that neural activity in the gamma band is critically associated with the control of feature binding.

  15. Beat characteristics and beat maps of the King Seong-deok Divine Bell

    Science.gov (United States)

    Kim, Seock-Hyun; Lee, Chi-Wook; Lee, Jang-Moo

    2005-03-01

    King Seong-deok Divine Bell is the second oldest bell in Korea. The bell is considered to have the best sound quality among Korean bells. The beat phenomenon is one of the most important characteristics for the sound of the King Seong-deok Divine Bell. In this study, the relationships between the modal parameters and the peculiar beat phenomena of the bell are investigated. It is theoretically proved from the beat characteristics that the sound might indeed be heard differently depending on the listening positions. The beat map method is introduced to visualize the beat distribution properties. It is shown that the beat maps can be drawn with a theoretical model based on the modal data of the bell. Using the beat maps of the King Seong-deok Divine Bell, it is investigated why clear and unclear beats, large and small amplitudes of the vibrations are repeated periodically along the circumference of the bell. Furthermore, the effect of the striking position on the beat distribution property is examined systematically.

  16. Possible parametric instabilities of beat waves in a transversely magnetized plasma

    International Nuclear Information System (INIS)

    Salimullah, M.

    1988-05-01

    The effect of an external magnetic field on the various possible parametric instabilities of the longitudinal beat wave at the difference frequency of two incident laser beams in a hot plasma has been thoeretically investigated. The kinetic equation is employed to obtain the nonlinear response of the magnetized electrons due to the nonlinear coupling of the beat wave with the low-frequency electrostatic plasma modes. It is noted that the growth rates of the three-wave and the four-wave parametric instabilities can be influenced by the external transverse magnetic field. (author). 20 refs, 3 figs

  17. Value of transmission electron microscopy for primary ciliary dyskinesia diagnosis in the era of molecular medicine: Genetic defects with normal and non-diagnostic ciliary ultrastructure.

    Science.gov (United States)

    Shapiro, Adam J; Leigh, Margaret W

    2017-01-01

    Primary ciliary dyskinesia (PCD) is a genetic disorder causing chronic oto-sino-pulmonary disease. No single diagnostic test will detect all PCD cases. Transmission electron microscopy (TEM) of respiratory cilia was previously considered the gold standard diagnostic test for PCD, but 30% of all PCD cases have either normal ciliary ultrastructure or subtle changes which are non-diagnostic. These cases are identified through alternate diagnostic tests, including nasal nitric oxide measurement, high-speed videomicroscopy analysis, immunofluorescent staining of axonemal proteins, and/or mutation analysis of various PCD causing genes. Autosomal recessive mutations in DNAH11 and HYDIN produce normal TEM ciliary ultrastructure, while mutations in genes encoding for radial spoke head proteins result in some cross-sections with non-diagnostic alterations in the central apparatus interspersed with normal ciliary cross-sections. Mutations in nexin link and dynein regulatory complex genes lead to a collection of different ciliary ultrastructures; mutations in CCDC65, CCDC164, and GAS8 produce normal ciliary ultrastructure, while mutations in CCDC39 and CCDC40 cause absent inner dynein arms and microtubule disorganization in some ciliary cross-sections. Mutations in CCNO and MCIDAS cause near complete absence of respiratory cilia due to defects in generation of multiple cellular basal bodies; however, the scant cilia generated may have normal ultrastructure. Lastly, a syndromic form of PCD with retinal degeneration results in normal ciliary ultrastructure through mutations in the RPGR gene. Clinicians must be aware of these genetic causes of PCD resulting in non-diagnostic TEM ciliary ultrastructure and refrain from using TEM of respiratory cilia as a test to rule out PCD.

  18. Walking to the beat of different drums: practical implications for the use of acoustic rhythms in gait rehabilitation.

    Science.gov (United States)

    Roerdink, Melvyn; Bank, Paulina J M; Peper, C Lieke E; Beek, Peter J

    2011-04-01

    Acoustic rhythms are frequently used in gait rehabilitation, with positive instantaneous and prolonged transfer effects on various gait characteristics. The gait modifying ability of acoustic rhythms depends on how well gait is tied to the beat, which can be assessed with measures of relative timing of auditory-motor coordination. We examined auditory-motor coordination in 20 healthy elderly individuals walking to metronome beats with pacing frequencies slower than, equal to, and faster than their preferred cadence. We found that more steps were required to adjust gait to the beat, the more the metronome rate deviated from the preferred cadence. Furthermore, participants anticipated the beat with their footfalls to various degrees, depending on the metronome rate; the faster the tempo, the smaller the phase advance or phase lead. Finally, the variability in the relative timing between footfalls and the beat was smaller for metronome rates closer to the preferred cadence, reflecting superior auditory-motor coordination. These observations have three practical implications. First, instantaneous effects of acoustic stimuli on gait characteristics may typically be underestimated given the considerable number of steps required to attune gait to the beat in combination with the usual short walkways. Second, a systematic phase lead of footfalls to the beat does not necessarily reflect a reduced ability to couple gait to the metronome. Third, the efficacy of acoustic rhythms to modify gait depends on metronome rate. Gait is coupled best to the beat for metronome rates near the preferred cadence. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Ventilation inhomogeneity in children with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Green, Kent; Buchvald, Frederik F; Marthin, June Kehlet

    2012-01-01

    The lung clearance index (LCI) derived from the multiple breath inert gas washout (MBW) test reflects global ventilation distribution inhomogeneity. It is more sensitive than forced expiratory volume in 1 s (FEV(1)) for detecting abnormal airway function and correlates closely with structural lung...... damage in children with cystic fibrosis, which shares features with primary ciliary dyskinesia (PCD). Normalised phase III slope indices S(cond) and S(acin) reflect function of the small conducting and acinar airways, respectively. The involvement of the peripheral airways assessed by MBW tests has...

  20. Proarrhythmic electrical remodelling is associated with increased beat-to-beat variability of repolarisation

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard; Oros, Avram; Schoenmakers, Marieke

    2007-01-01

    Acquired long-QT syndrome in combination with increased beat-to-beat variability of repolarisation duration (BVR) is associated with lethal torsades de pointes arrhythmias (TdP) in dogs with remodelled heart after atrioventricular block (AVB). We evaluated the relative contributions of bradycardi...

  1. Effects of adriamycin and irradiation on beating of rat heart muscle cells in culture

    International Nuclear Information System (INIS)

    Petrovic, D.; Brown, S.M.; Yatvin, M.B.

    1977-01-01

    In an attempt to elucidate the mechanisms involved in Adriamycin (ADM) induced cardiotoxicity as well as determining the possible potentiating effect that irradiation has when it is combined with the drug, heart cells from newborn rats were isolated, cultured and treated with Adriamycin. The actions of these two agents separately or in combination on the survival of beating activity and beating frequency are measured. Beating activity could be decreased temporarily either by exposing the cells to 50 krad of γ-irradiation or 0.1 μg of Adriamycin. Following 100 krad of γ-radiation or 1.0 μg Adriamycin, an irreversible cessation of beating occurred. In the case of Adriamycin, cessation was preceded by a temporary sharp increase in beating frequency. Doses of radiation up to 10 krad in combination with Adriamycin were not potentiating. The results indicate that Adriamycin produces its cardiotoxic effects, at least in part, by a direct action on heart muscle cells. It is less likely, however, that damage which occurs in the heart following therapeutic doses of irradiation is the result of such direct action

  2. Beat-wave excitation and current driven in tokamak plasma. Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, B F [Plasma physics Department, Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    Wave heating current drive in tokamaks is a growing subject in the plasma physics literature. For current drive in tokamaks by electromagnetic waves, different methods have been proposed recently. One of the promising schemes for current drive remains the beat wave scheme. This technique employs two CO- or counterpropagating monochromatic laser beams (or microwaves) whose frequency difference matches the plasma frequency, while the wave number difference (or sum, in the case of counterpropagating) determine the wave number of the resulting plasma beat wave. In this work, the basic analysis of a beat wave current drive scheme in which collinear waves are used is discussed. by assuming a Gaussian profile for the amplitude of these pump waves, the amplitudes of the longitudinal and radial fields of the beat wave due to the nonlinear wave interactions have been calculated. Besides, the transfer of momentum flux that accompanies the transfer of wave action in beat-wave scattering will be used to drive the toroidal radial currents in tokamaks. self-generated magnetic fields due to those currents were also calculated. 1 fig.

  3. Oligodendroglioma of the ciliary body: a unique case report and the review of literature

    International Nuclear Information System (INIS)

    Guo, Qing; Hao, Jie; Sun, Shou bin; Xu, Shou ping; Yang, Qian; Guo, Qi liang; Cui, Guo dong

    2010-01-01

    To date, there is no report in the international literature of an oligodendroglioma of the ciliary body, nor is there an analysis of the possible origins of this lesion. Here we report on a 52-year-old man admitted to our hospital with a ciliary body tumor revealed by clinical examination and ultrasound, computed tomography and magnetic resonance imaging studies. Following enucleation, pathological and immunohistochemical analyses were performed. Postoperative histopathological staining results included OLIGO-2(+) and GFAP(-), leading to a pathological diagnosis of oligodendroglioma of the ciliary body in the right eye (WHO grade II). Since malignant gliomas derive from transformed neural stem cells, the presence of oligodendroglioma in the ciliary body supports the hypothesis that gliomas can occur wherever neural stem cells exist. Tumors of the ciliary body derived from oligodendrocytes are difficult to diagnose; pathological analyses are essential

  4. High beat-to-beat blood pressure variability in atrial fibrillation compared to sinus rhythm.

    Science.gov (United States)

    Olbers, Joakim; Gille, Adam; Ljungman, Petter; Rosenqvist, Mårten; Östergren, Jan; Witt, Nils

    2018-02-07

    Atrial fibrillation (AF) is associated with an increased risk for cardiovascular morbidity and mortality, not entirely explained by thromboembolism. The underlying mechanisms for this association are largely unknown. Similarly, high blood pressure (BP) increases the risk for cardiovascular events. Despite this the interplay between AF and BP is insufficiently studied. The purpose of this study was to examine and quantify the beat-to-beat blood pressure variability in patients with AF in comparison to a control group of patients with sinus rhythm. We studied 33 patients - 21 in atrial fibrillation and 12 in sinus rhythm - undergoing routine coronary angiography. Invasive blood pressure was recorded at three locations: radial artery, brachial artery and ascending aorta. Blood pressure variability, defined as average beat-to-beat blood pressure difference, was calculated for systolic and diastolic blood pressure at each site. We observed a significant difference (p blood pressure variability between the atrial fibrillation and sinus rhythm groups at all locations. Systolic blood pressure variability roughly doubled in the atrial fibrillation group compared to the sinus rhythm group (4.9 and 2.4 mmHg respectively). Diastolic beat-to-beat blood pressure variability was approximately 6 times as high in the atrial fibrillation group compared to the sinus rhythm group (7.5 and 1.2 mmHg respectively). No significant difference in blood pressure variability was seen between measurement locations. Beat-to-beat blood pressure variability in patients with atrial fibrillation was substantially higher than in patients with sinus rhythm. Hemodynamic effects of this beat-to-beat variation in blood pressure may negatively affect vascular structure and function, which may contribute to the increased cardiovascular morbidity and mortality seen in patients with atrial fibrillation.

  5. Methods for Studying Ciliary-Mediated Chemoresponse in Paramecium.

    Science.gov (United States)

    Valentine, Megan Smith; Van Houten, Judith L

    2016-01-01

    Paramecium is a useful model organism for the study of ciliary-mediated chemical sensing and response. Here we describe ways to take advantage of Paramecium to study chemoresponse.Unicellular organisms like the ciliated protozoan Paramecium sense and respond to chemicals in their environment (Van Houten, Ann Rev Physiol 54:639-663, 1992; Van Houten, Trends Neurosci 17:62-71, 1994). A thousand or more cilia that cover Paramecium cells serve as antennae for chemical signals, similar to ciliary function in a large variety of metazoan cell types that have primary or motile cilia (Berbari et al., Curr Biol 19(13):R526-R535, 2009; Singla V, Reiter J, Science 313:629-633, 2006). The Paramecium cilia also produce the motor output of the detection of chemical cues by controlling swimming behavior. Therefore, in Paramecium the cilia serve multiple roles of detection and response.We present this chapter in three sections to describe the methods for (1) assaying populations of cells for their behavioral responses to chemicals (attraction and repulsion), (2) characterization of the chemoreceptors and associated channels of the cilia using proteomics and binding assays, and (3) electrophysiological analysis of individual cells' responses to chemicals. These methods are applied to wild type cells, mutants, transformed cells that express tagged proteins, and cells depleted of gene products by RNA Interference (RNAi).

  6. Measuring Neural Entrainment to Beat and Meter in Infants: Effects of Music Background

    Science.gov (United States)

    Cirelli, Laura K.; Spinelli, Christina; Nozaradan, Sylvie; Trainor, Laurel J.

    2016-01-01

    Caregivers often engage in musical interactions with their infants. For example, parents across cultures sing lullabies and playsongs to their infants from birth. Behavioral studies indicate that infants not only extract beat information, but also group these beats into metrical hierarchies by as early as 6 months of age. However, it is not known how this is accomplished in the infant brain. An EEG frequency-tagging approach has been used successfully with adults to measure neural entrainment to auditory rhythms. The current study is the first to use this technique with infants in order to investigate how infants' brains encode rhythms. Furthermore, we examine how infant and parent music background is associated with individual differences in rhythm encoding. In Experiment 1, EEG was recorded while 7-month-old infants listened to an ambiguous rhythmic pattern that could be perceived to be in two different meters. In Experiment 2, EEG was recorded while 15-month-old infants listened to a rhythmic pattern with an unambiguous meter. In both age groups, information about music background (parent music training, infant music classes, hours of music listening) was collected. Both age groups showed clear EEG responses frequency-locked to the rhythms, at frequencies corresponding to both beat and meter. For the younger infants (Experiment 1), the amplitudes at duple meter frequencies were selectively enhanced for infants enrolled in music classes compared to those who had not engaged in such classes. For the older infants (Experiment 2), amplitudes at beat and meter frequencies were larger for infants with musically-trained compared to musically-untrained parents. These results suggest that the frequency-tagging method is sensitive to individual differences in beat and meter processing in infancy and could be used to track developmental changes. PMID:27252619

  7. VLF wave generation by beating of two HF waves in the ionosphere

    Science.gov (United States)

    Kuo, Spencer; Snyder, Arnold; Kossey, Paul; Chang, Chia-Lie; Labenski, John

    2011-05-01

    Theory of a beat-wave mechanism for very low frequency (VLF) wave generation in the ionosphere is presented. The VLF current is produced by beating two high power HF waves of slightly different frequencies through the nonlinearity and inhomogeneity of the ionospheric plasma. Theory also shows that the density irregularities can enhance the beat-wave generation. An experiment was conducted by transmitting two high power HF waves of 3.2 MHz and 3.2 MHz + f, where f = 5, 8, 13, and 2.02 kHz, from the HAARP transmitter. In the experiment, the ionosphere was underdense to the O-mode heater, i.e., the heater frequency f0 > foF2, and overdense or slightly underdense to the X-mode heater, i.e., f0 < fxF2 or f0 ≥ fxF2. The radiation intensity increased with the VLF wave frequency, was much stronger with the X-mode heaters, and was not sensitive to the electrojet. The strongest VLF radiation of 13 kHz was generated when the reflection layer of the X-mode heater was just slightly below the foF2 layer and the spread of the O-mode sounding echoes had the largest enhancement, suggesting an optimal setting for beat-wave generation of VLF waves by the HF heaters.

  8. Hyperfine splitting in positronium measured through quantum beats in the 3γ decay

    International Nuclear Information System (INIS)

    Fan, S.; Beling, C.D.; Fung, S.

    1996-01-01

    Quantum beat oscillations in the 3γ decay of the positronium atom arising from interference between the different spin states have been observed using a simple β-start and γ-stop detection system. Measurements of the beat frequency at different magnetic fields have yielded a value of the 1 1 S 0 -1 3 S 1 hyperfine interaction of 202.5±3.5 GHz, in good agreement with previous measurements. This novel approach does not require high magnetic fields and the use of microwave radiation to quench the triplet substate of the positronium atom. (orig.)

  9. A comparison of auditory evoked potentials to acoustic beats and to binaural beats

    OpenAIRE

    Pratt, H; Starr, A; Michalewski, HJ; Dimitrijevic, A; Bleich, N; Mittelman, N

    2010-01-01

    The purpose of this study was to compare cortical brain responses evoked by amplitude modulated acoustic beats of 3 and 6 Hz in tones of 250 and 1000 Hz with those evoked by their binaural beats counterparts in unmodulated tones to indicate whether the cortical processes involved differ. Event-related potentials (ERPs) were recorded to 3- and 6-Hz acoustic and binaural beats in 2000 ms duration 250 and 1000 Hz tones presented with approximately 1 s intervals. Latency, amplitude and source cur...

  10. Eliminating the Attentional Blink through Binaural Beats: A Case for Tailored Cognitive Enhancement.

    Science.gov (United States)

    Reedijk, Susan A; Bolders, Anne; Colzato, Lorenza S; Hommel, Bernhard

    2015-01-01

    Enhancing human cognitive performance is a topic that continues to spark scientific interest. Studies into cognitive-enhancement techniques often fail to take inter-individual differences into account, however, which leads to underestimation of the effectiveness of these techniques. The current study investigated the effect of binaural beats, a cognitive-enhancement technique, on attentional control in an attentional blink (AB) task. As predicted from a neurocognitive approach to cognitive control, high-frequency binaural beats eliminated the AB, but only in individuals with low spontaneous eye-blink rates (indicating low striatal dopamine levels). This suggests that the way in which cognitive-enhancement techniques, such as binaural beats, affect cognitive performance depends on inter-individual differences.

  11. Eliminating the attentional blink through binaural beats: A case for tailored cognitive enhancement

    Directory of Open Access Journals (Sweden)

    Susan A. Reedijk

    2015-06-01

    Full Text Available Enhancing human cognitive performance is a topic that continues to spark scientific interest. Studies into cognitive enhancement techniques often fail to take inter-individual differences into account, however, which leads to underestimation of the effectiveness of these techniques. The current study investigated the effect of binaural beats, a cognitive enhancement technique, on attentional control in an attentional blink task. As predicted from a neurocognitive approach to cognitive control, high-frequency binaural beats eliminated the attentional blink, but only in individuals with low spontaneous eye-blink rates (indicating low striatal dopamine levels. This suggests that the way in which cognitive enhancement techniques, such as binaural beats, affect cognitive performance depends on inter-individual differences.

  12. Beat my bass, pluck my drum

    NARCIS (Netherlands)

    Hengeveld, B.J.; Funk, M.; Doing, V.

    2014-01-01

    Beating a bass, plucking a drum -- new systems of instruments make it possible. In this paper we describe recent research into networked musical instruments for group improvisation; instruments that reciprocally influence each other's behaviour, making, contrary to what we are used to, the

  13. A Good Suit Beats a Good Idea.

    Science.gov (United States)

    Machiavelli, Nick

    1992-01-01

    Inspired by Niccolo Machiavelli, this column offers beleaguered school executives advice on looking good, dressing well, losing weight, beating the proper enemy, and saying nothing. Administrators who follow these simple rules should have an easier life, jealous colleagues, well-tended gardens, and respectful board members. (MLH)

  14. Beat the Instructor: An Introductory Forecasting Game

    Science.gov (United States)

    Snider, Brent R.; Eliasson, Janice B.

    2013-01-01

    This teaching brief describes a 30-minute game where student groups compete in-class in an introductory time-series forecasting exercise. The students are challenged to "beat the instructor" who competes using forecasting techniques that will be subsequently taught. All forecasts are graphed prior to revealing the randomly generated…

  15. Finger-to-beat coordination skill of non-dancers, street dancers, and the world champion of a street-dance competition

    Directory of Open Access Journals (Sweden)

    Akito eMiura

    2016-04-01

    Full Text Available The coordination of body movements to a musical beat is a common feature of many dance styles. However, the auditory-motor coordination skills of dancers remain largely uninvestigated. The purpose of this study was to examine the auditory-motor coordination skills of non-dancers, street dancers, and the winner of a celebrated international street dance competition, while coordinating their rhythmic finger movements to a beat. The beat rate of a metronome increased from 1.0 to 3.7 Hz. The participants were asked to either flex or extend their index fingers on the beat in each condition. Under the extend-on-the-beat condition, both the dancers and non-dancers showed a spontaneous transition from the extend-on-the-beat to the flex-on-the-beat or to a phase wandering pattern. However, the critical frequency at which the transition occurred was significantly higher in the dancers (3.3 Hz than in the non-dancers (2.6 Hz. Under the flex-on-the-beat condition, the dancers were able to maintain their coordination pattern more stably at high beat rates compared to the non-dancers. Furthermore, the world champion matched the timing of movement peak velocity to the beat across the different beat rates. This may give a sense of unity between the movement and the beat for the audience because the peak velocity of the rhythmic movement works as a temporal cue for the audiovisual synchrony perception. These results suggest that the skills of accomplished dancers lie in their small finger movements and that the sensorimotor learning of street dance is characterized by a stabilization of the coordination patterns, including the inhibition of an unintentional transition to other coordination patterns.

  16. Small displacement measurements with subatomic resolution by beat frequency measurements

    Czech Academy of Sciences Publication Activity Database

    Číp, Ondřej; Petrů, František; Buchta, Zdeněk; Lazar, Josef

    2007-01-01

    Roč. 18, č. 7 (2007), s. 2005-2013 ISSN 0957-0233 R&D Projects: GA AV ČR KJB200650503; GA MŠk(CZ) LC06007; GA ČR GA102/07/1179; GA MPO FT-TA3/133 Institutional research plan: CEZ:AV0Z20650511 Keywords : high-resolution interferometry * nanometrology Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.297, year: 2007

  17. Model for the heart beat-to-beat time series during meditation

    Science.gov (United States)

    Capurro, A.; Diambra, L.; Malta, C. P.

    2003-09-01

    We present a model for the respiratory modulation of the heart beat-to-beat interval series. The model consists of a pacemaker, that simulates the membrane potential of the sinoatrial node, modulated by a periodic input signal plus correlated noise that simulates the respiratory input. The model was used to assess the waveshape of the respiratory signals needed to reproduce in the phase space the trajectory of experimental heart beat-to-beat interval data. The data sets were recorded during meditation practices of the Chi and Kundalini Yoga techniques. Our study indicates that in the first case the respiratory signal has the shape of a smoothed square wave, and in the second case it has the shape of a smoothed triangular wave.

  18. Airway ciliary dysfunction and respiratory symptoms in patients with transposition of the great arteries.

    Science.gov (United States)

    Zahid, Maliha; Bais, Abha; Tian, Xin; Devine, William; Lee, Dong Ming; Yau, Cyrus; Sonnenberg, Daniel; Beerman, Lee; Khalifa, Omar; Lo, Cecilia W

    2018-01-01

    Our prior work on congenital heart disease (CHD) with heterotaxy, a birth defect involving randomized left-right patterning, has shown an association of a high prevalence of airway ciliary dysfunction (CD; 18/43 or 42%) with increased respiratory symptoms. Furthermore, heterotaxy patients with ciliary dysfunction were shown to have more postsurgical pulmonary morbidities. These findings are likely a reflection of the common role of motile cilia in both airway clearance and left-right patterning. As CHD comprising transposition of the great arteries (TGA) is commonly thought to involve disturbance of left-right patterning, especially L-TGA with left-right ventricular inversion, we hypothesize CHD patients with transposition of great arteries (TGA) may have high prevalence of airway CD with increased respiratory symptoms. We recruited 75 CHD patients with isolated TGA, 28% L and 72% D-TGA. Patients were assessed using two tests typically used for evaluating airway ciliary dysfunction in patients with primary ciliary dyskinesia (PCD), a recessive sinopulmonary disease caused by respiratory ciliary dysfunction. This entailed the measurement of nasal nitric oxide (nNO), which is typically low with PCD. We also obtained nasal scrapes and conducted videomicroscopy to assess respiratory ciliary motion (CM). We observed low nNO in 29% of the patients, and abnormal CM in 57%, with 22% showing both low nNO and abnormal CM. No difference was observed for the prevalence of either low nNO or abnormal ciliary motion between patients with D vs. L-TGA. Respiratory symptoms were increased with abnormal CM, but not low nNO. Sequencing analysis showed no compound heterozygous or homozygous mutations in 39 genes known to cause PCD, nor in CFTR, gene causing cystic fibrosis. As both are recessive disorders, these results indicate TGA patients with ciliary dysfunction do not have PCD or cystic fibrosis (which can cause low nNO or abnormal ciliary motion). TGA patients have high

  19. Genotypic variation for salinity tolerance in Cenchrus ciliaris L

    Directory of Open Access Journals (Sweden)

    M. Iftikhar Hussain

    2016-07-01

    Full Text Available Scarcity of irrigation water and increasing soil salinization has threatened the sustainability of forage production in arid and semi-arid region around the globe. Introduction of salt-tolerant perennial species is a promising alternative to overcome forage deficit to meet future livestock needs in salt-affected areas. This study presents the results of a salinity tolerance screening trial which was carried out in plastic pots buried in the open field for 160 buffelgrass (Cenchrus ciliaris L. accessions for three consecutive years (2003-2005. The plastic pots were filled with sand, organic, and peat moss mix and were irrigated with four different quality water (EC 0, 10, 15, and 20 dS m-1. The results indicate that the average annual dry weights (DW were in the range from 122.5 – 148.9 g pot-1 in control; 96.4 – 133.8 g pot-1 at 10 dS m-1; 65.6 – 80.4 g pot-1 at 15 dS m-1, and 55.4- 65.6 g pot-1 at 20 dS m-1. The highest DW (148.9 g pot-1 was found with accession 49 and the lowest with accession 23. Principle component analysis shows that PC-1 contributed 81.8 % of the total variability, while PC-2 depicted 11.7% of the total variation among C. ciliaris accessions for DW. Hierarchical cluster analysis revealed that a number of accessions collected from diverse regions could be grouped into a single cluster. Accessions 3, 133, 159, 30, 23, 142, 141, 95, 49, 129, 124, and 127 were stable, salt tolerant, and produced good dry biomass yield. These accessions demonstrate sufficient salinity tolerance potential for promotion in marginal land and arid regions to enhance farm productivity and reduce rural poverty.

  20. Relationship between age and location of the apex beat among ...

    African Journals Online (AJOL)

    Location of apex beat is an integral part of routine cardiovascular system examination in clinical practice. However, there is paucity of ... Apex beat location in the intercostal space was determined and distance of apex beat from the midline, midclavicular line and nipple lines were measured. The measured distances were ...

  1. Rhythmic regularity revisited : Is beat induction indeed pre-attentive?

    NARCIS (Netherlands)

    Bouwer, F.; Honing, H.; Cambouropoulos, E.; Tsougras, C.; Mavromatis, P.; Pastiadis, K.

    2012-01-01

    When listening to musical rhythm, regularity in time is often perceived in the form of a beat or pulse. External rhythmic events can give rise to the perception of a beat, through a process known as beat induction. In addition, internal processes, like long-term memory, working memory and automatic

  2. Model for the respiratory modulation of the heart beat-to-beat time interval series

    Science.gov (United States)

    Capurro, Alberto; Diambra, Luis; Malta, C. P.

    2005-09-01

    In this study we present a model for the respiratory modulation of the heart beat-to-beat interval series. The model consists of a set of differential equations used to simulate the membrane potential of a single rabbit sinoatrial node cell, excited with a periodic input signal with added correlated noise. This signal, which simulates the input from the autonomous nervous system to the sinoatrial node, was included in the pacemaker equations as a modulation of the iNaK current pump and the potassium current iK. We focus at modeling the heart beat-to-beat time interval series from normal subjects during meditation of the Kundalini Yoga and Chi techniques. The analysis of the experimental data indicates that while the embedding of pre-meditation and control cases have a roughly circular shape, it acquires a polygonal shape during meditation, triangular for the Kundalini Yoga data and quadrangular in the case of Chi data. The model was used to assess the waveshape of the respiratory signals needed to reproduce the trajectory of the experimental data in the phase space. The embedding of the Chi data could be reproduced using a periodic signal obtained by smoothing a square wave. In the case of Kundalini Yoga data, the embedding was reproduced with a periodic signal obtained by smoothing a triangular wave having a rising branch of longer duration than the decreasing branch. Our study provides an estimation of the respiratory signal using only the heart beat-to-beat time interval series.

  3. Unraveling the nature of coherent beatings in chlorosomes

    Energy Technology Data Exchange (ETDEWEB)

    Dostál, Jakub [Department of Chemical Physics, Lund University, P.O. Box 124, SE-22100 Lund (Sweden); Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague (Czech Republic); Mančal, Tomáš; Pšenčík, Jakub [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague (Czech Republic); Vácha, František [Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice (Czech Republic); Zigmantas, Donatas, E-mail: donatas.zigmantas@chemphys.lu.se [Department of Chemical Physics, Lund University, P.O. Box 124, SE-22100 Lund (Sweden)

    2014-03-21

    Coherent two-dimensional (2D) spectroscopy at 80 K was used to study chlorosomes isolated from green sulfur bacterium Chlorobaculum tepidum. Two distinct processes in the evolution of the 2D spectrum are observed. The first being exciton diffusion, seen in the change of the spectral shape occurring on a 100-fs timescale, and the second being vibrational coherences, realized through coherent beatings with frequencies of 91 and 145 cm{sup −1} that are dephased during the first 1.2 ps. The distribution of the oscillation amplitude in the 2D spectra is independent of the evolution of the 2D spectral shape. This implies that the diffusion energy transfer process does not transfer coherences within the chlorosome. Remarkably, the oscillatory pattern observed in the negative regions of the 2D spectrum (dominated by the excited state absorption) is a mirror image of the oscillations found in the positive part (originating from the stimulated emission and ground state bleach). This observation is surprising since it is expected that coherences in the electronic ground and excited states are generated with the same probability and the latter dephase faster in the presence of fast diffusion. Moreover, the relative amplitude of coherent beatings is rather high compared to non-oscillatory signal despite the reported low values of the Huang-Rhys factors. The origin of these effects is discussed in terms of the vibronic and Herzberg-Teller couplings.

  4. Simultaneous sinus and lung infections in patients with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Alanin, Mikkel Christian; Johansen, Helle Krogh; Aanaes, Kasper

    2015-01-01

    Conclusion: The sinuses should be considered as a bacterial reservoir and a target for surgery and antibiotic treatment in patients with primary ciliary dyskinesia (PCD). The observed decrease in serum precipitating antibodies (precipitins) against Pseudomonas aeruginosa may indicate a beneficial...

  5. Circumferential Ciliary Body Cysts Presenting as Acute Pigment Dispersion and Ocular Hypertension.

    Science.gov (United States)

    Sarıgül Sezenöz, Almila; Güngör, Sirel Gür; Kıratlı, Hayyam; Akman, Ahmet

    2017-09-15

    To report a case of circumferential neuroepithelial cyst of the ciliary body presenting with pigment dispersion (PD) and ocular hypertension. 48-year-old female patient presented with a complaint of pain in the left eye. On examination, visual acuity of the left eye was 0.9, and the intraocular pressure was 48 mmHg. Biomicroscopic anterior segment examination of the left eye revealed 4+ pigmented cells in the anterior chamber. Active PD from the pupillary region at 11 o'clock was noticed at the time of the examination. Ultrasound biomicroscopy demonstrated 360º cystic lesions of the ciliary body in the left eye. The patient was diagnosed as neuroepithelial cyst of the ciliary body. Our case is unique as it is the first case of circumferential neuroepithelial ciliary body cyst presenting with acute PD and ocular hypertension.

  6. ICK is essential for cell type-specific ciliogenesis and the regulation of ciliary transport.

    Science.gov (United States)

    Chaya, Taro; Omori, Yoshihiro; Kuwahara, Ryusuke; Furukawa, Takahisa

    2014-06-02

    Cilia and flagella are formed and maintained by intraflagellar transport (IFT) and play important roles in sensing and moving across species. At the distal tip of the cilia/flagella, IFT complexes turn around to switch from anterograde to retrograde transport; however, the underlying regulatory mechanism is unclear. Here, we identified ICK localization at the tip of cilia as a regulator of ciliary transport. In ICK-deficient mice, we found ciliary defects in neuronal progenitor cells with Hedgehog signal defects. ICK-deficient cells formed cilia with mislocalized Hedgehog signaling components. Loss of ICK caused the accumulation of IFT-A, IFT-B, and BBSome components at the ciliary tips. In contrast, overexpression of ICK induced the strong accumulation of IFT-B, but not IFT-A or BBSome components at ciliary tips. In addition, ICK directly phosphorylated Kif3a, while inhibition of this Kif3a phosphorylation affected ciliary formation. Our results suggest that ICK is a Kif3a kinase and essential for proper ciliogenesis in development by regulating ciliary transport at the tip of cilia. © 2014 The Authors.

  7. The impact of binaural beats on creativity

    OpenAIRE

    Susan A. Reedijk; Susan A. Reedijk; Anne eBolders; Anne eBolders; Bernhard eHommel; Bernhard eHommel

    2013-01-01

    Human creativity relies on a multitude of cognitive processes, some of which are influenced by the neurotransmitter dopamine. This suggests that creativity could be enhanced by interventions that either modulate the production or transmission of dopamine directly, or affect dopamine-driven processes. In the current study we hypothesized that creativity can be influenced by means of binaural beats, an auditory illusion that is considered a form of cognitive entrainment that operates through st...

  8. Exogenous ciliary neurotrophic factor (CNTF) reduces synaptic depression during repetitive stimulation.

    Science.gov (United States)

    Garcia, Neus; Santafé, Manel M; Tomàs, Marta; Priego, Mercedes; Obis, Teresa; Lanuza, Maria A; Besalduch, Nuria; Tomàs, Josep

    2012-09-01

    It has been shown that ciliary neurotrophic factor (CNTF) has trophic and maintenance effects on several types of peripheral and central neurons, glia, and cells outside the nervous system. Both CNTF and its receptor, CNTF-Rα, are expressed in the muscle. We use confocal immunocytochemistry to show that the trophic cytokine and its receptor are present in the pre- and post-synaptic sites of the neuromuscular junctions (NMJs). Applied CNTF (7.5-200 ng/ml, 60 min-3 h) does not acutely affect spontaneous potentials (size or frequency) or quantal content of the evoked acetylcholine release from post-natal (in weak or strong axonal inputs on dually innervated end plates or in the most mature singly innervated synapses at P6) or adult (P30) NMJ of Levator auris longus muscle of the mice. However, CNTF reduces roughly 50% the depression produced by repetitive stimulation (40 Hz, 2 min) on the adult NMJs. Our findings indicate that, unlike neurotrophins, exogenous CNTF does not acutely modulate transmitter release locally at the mammalian neuromuscular synapse but can protect mature end plates from activity-induced synaptic depression. © 2012 Peripheral Nerve Society.

  9. Beat-to-beat left ventricular performance in atrial fibrillation: radionuclide assessment with the computerized nuclear probe

    International Nuclear Information System (INIS)

    Schneider, J.; Berger, H.J.; Sands, M.J.; Lachman, A.B.; Zaret, B.L.

    1983-01-01

    There is wide beat-to-beat variability in cycle length and left ventricular performance in patients with atrial fibrillation. In this study, left ventricular ejection fraction and relative left ventricular volumes were evaluated on a beat-to-beat basis with the computerized nuclear probe, an instrument with sufficiently high sensitivity to allow continuous evaluation of the radionuclide time-activity curve. Of 18 patients with atrial fibrillation, 5 had mitral stenosis, 6 had mitral regurgitation, and 7 had coronary artery disease. Fifty consecutive beats were analyzed in each patient. The mean left ventricular ejection fraction ranged from 17 to 51%. There was substantial beat-to-beat variation in cycle length and left ventricular ejection fraction in all patients, including those with marked left ventricular dysfunction. In 14 patients who also underwent multiple gated cardiac blood pool imaging, there was an excellent correlation between mean ejection fraction derived from the nuclear probe and gated ejection fraction obtained by gamma camera imaging (r . 0.90). Based on beat-to-beat analysis, left ventricular function was dependent on relative end-diastolic volume and multiple preceding cycle lengths, but not preceding end-systolic volumes. This study demonstrates that a single value for left ventricular ejection fraction does not adequately characterize left ventricular function in patients with atrial fibrillation. Furthermore, both the mean beat-to-beat and the gated ejection fraction may underestimate left ventricular performance at rest in such patients

  10. Semiconductor optical amplifier-based heterodyning detection for resolving optical terahertz beat-tone signals from passively mode-locked semiconductor lasers

    International Nuclear Information System (INIS)

    Latkowski, Sylwester; Maldonado-Basilio, Ramon; Carney, Kevin; Parra-Cetina, Josue; Philippe, Severine; Landais, Pascal

    2010-01-01

    An all-optical heterodyne approach based on a room-temperature controlled semiconductor optical amplifier (SOA) for measuring the frequency and linewidth of the terahertz beat-tone signal from a passively mode-locked laser is proposed. Under the injection of two external cavity lasers, the SOA acts as a local oscillator at their detuning frequency and also as an optical frequency mixer whose inputs are the self-modulated spectrum of the device under test and the two laser beams. Frequency and linewidth of the intermediate frequency signal (and therefore, the beat-tone signal) are resolved by using a photodiode and an electrical spectrum analyzer.

  11. Binaural beats increase interhemispheric alpha-band coherence between auditory cortices.

    Science.gov (United States)

    Solcà, Marco; Mottaz, Anaïs; Guggisberg, Adrian G

    2016-02-01

    Binaural beats (BBs) are an auditory illusion occurring when two tones of slightly different frequency are presented separately to each ear. BBs have been suggested to alter physiological and cognitive processes through synchronization of the brain hemispheres. To test this, we recorded electroencephalograms (EEG) at rest and while participants listened to BBs or a monaural control condition during which both tones were presented to both ears. We calculated for each condition the interhemispheric coherence, which expressed the synchrony between neural oscillations of both hemispheres. Compared to monaural beats and resting state, BBs enhanced interhemispheric coherence between the auditory cortices. Beat frequencies in the alpha (10 Hz) and theta (4 Hz) frequency range both increased interhemispheric coherence selectively at alpha frequencies. In a second experiment, we evaluated whether this coherence increase has a behavioral aftereffect on binaural listening. No effects were observed in a dichotic digit task performed immediately after BBs presentation. Our results suggest that BBs enhance alpha-band oscillation synchrony between the auditory cortices during auditory stimulation. This effect seems to reflect binaural integration rather than entrainment. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Bio-inspired ciliary force sensor for robotic platforms

    KAUST Repository

    Ribeiro, Pedro

    2017-01-20

    The detection of small forces is of great interest in any robotic application that involves interaction with the environment (e.g., objects manipulation, physical human-robot interaction, minimally invasive surgery), since it allows the robot to detect the contacts early on and to act accordingly. In this letter, we present a sensor design inspired by the ciliary structure frequently found in nature, consisting of an array of permanently magnetized cylinders (cilia) patterned over a giant magnetoresistance sensor (GMR). When these cylinders are deformed in shape due to applied forces, the stray magnetic field variation will change the GMR sensor resistivity, thus enabling the electrical measurement of the applied force. In this letter, we present two 3 mm × 3 mm prototypes composed of an array of five cilia with 1 mm of height and 120 and 200 μm of diameter for each prototype. A minimum force of 333 μN was measured. A simulation model for determining the magnetized cylinders average stray magnetic field is also presented.

  13. Bio-inspired ciliary force sensor for robotic platforms

    KAUST Repository

    Ribeiro, Pedro; Khan, Mohammed Asadullah; Alfadhel, Ahmed; Kosel, Jü rgen; Franco, Fernando; Cardoso, Susana; Bernardino, Alexandre; Schmitz, Alexander; Santos-Victor, Jose; Jamone, Lorenzo

    2017-01-01

    The detection of small forces is of great interest in any robotic application that involves interaction with the environment (e.g., objects manipulation, physical human-robot interaction, minimally invasive surgery), since it allows the robot to detect the contacts early on and to act accordingly. In this letter, we present a sensor design inspired by the ciliary structure frequently found in nature, consisting of an array of permanently magnetized cylinders (cilia) patterned over a giant magnetoresistance sensor (GMR). When these cylinders are deformed in shape due to applied forces, the stray magnetic field variation will change the GMR sensor resistivity, thus enabling the electrical measurement of the applied force. In this letter, we present two 3 mm × 3 mm prototypes composed of an array of five cilia with 1 mm of height and 120 and 200 μm of diameter for each prototype. A minimum force of 333 μN was measured. A simulation model for determining the magnetized cylinders average stray magnetic field is also presented.

  14. Hearing loss in children with primary ciliary dyskinesia.

    Science.gov (United States)

    Kreicher, Kathryn L; Schopper, Heather K; Naik, Akash N; Hatch, Jonathan L; Meyer, Ted A

    2018-01-01

    To evaluate the type and severity of hearing impairment in pediatric patients with primary ciliary dyskinesia (PCD) and relate these measures to patient demographics, treatment options, and other otologic factors. A retrospective analysis of children with a diagnosis of PCD, Kartagener's syndrome, or situs inversus in the AudGen Database was conducted. Audiograms were analyzed for type of hearing loss (HL), severity, laterality, and progression. Medical charts were reviewed to identify factors that influence severity and progression of hearing loss. 56 patients met inclusion criteria and 42 patients had HL. 66.6% had bilateral and 33.3% had unilateral loss (70 total ears with HL). Conductive hearing loss (CHL) was the most common type of HL, though 30% of children had some sensorineural component to their hearing loss. 92.9% of children with HL received at least one diagnosis of otitis media, but HL did not improve in the majority (77.8%) of ears in our study regardless of ear tube placement. Slight to mild CHL and all types of otitis media are prevalent among patients with PCD, and some of these children have sensorineural hearing loss (SNHL). All patients diagnosed with situs inversus at birth should be evaluated by an otolaryngologist. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Beat-to-beat heart rate estimation fusing multimodal video and sensor data.

    Science.gov (United States)

    Antink, Christoph Hoog; Gao, Hanno; Brüser, Christoph; Leonhardt, Steffen

    2015-08-01

    Coverage and accuracy of unobtrusively measured biosignals are generally relatively low compared to clinical modalities. This can be improved by exploiting redundancies in multiple channels with methods of sensor fusion. In this paper, we demonstrate that two modalities, skin color variation and head motion, can be extracted from the video stream recorded with a webcam. Using a Bayesian approach, these signals are fused with a ballistocardiographic signal obtained from the seat of a chair with a mean absolute beat-to-beat estimation error below 25 milliseconds and an average coverage above 90% compared to an ECG reference.

  16. Inactivation of Ca2+-induced ciliary reversal by high-salt extraction in the cilia of Paramecium.

    Science.gov (United States)

    Kutomi, Osamu; Seki, Makoto; Nakamura, Shogo; Kamachi, Hiroyuki; Noguchi, Munenori

    2013-10-01

    Intracellular Ca(2+) induces ciliary reversal and backward swimming in Paramecium. However, it is not known how the Ca(2+) signal controls the motor machinery to induce ciliary reversal. We found that demembranated cilia on the ciliated cortical sheets from Paramecium caudatum lost the ability to undergo ciliary reversal after brief extraction with a solution containing 0.5 M KCl. KNO(3), which is similar to KCl with respect to chaotropic effect; it had the same effect as that of KCl on ciliary response. Cyclic AMP antagonizes Ca(2+)-induced ciliary reversal. Limited trypsin digestion prevents endogenous A-kinase and cAMP-dependent phosphorylation of an outer arm dynein light chain and induces ciliary reversal. However, the trypsin digestion prior to the high-salt extraction did not affect the inhibition of Ca(2+)-induced ciliary reversal caused by the high-salt extraction. Furthermore, during the course of the high-salt extraction, some axonemal proteins were extracted from ciliary axonemes, suggesting that they may be responsible for Ca(2+)-induced ciliary reversal.

  17. cAMP Stimulates Transepithelial Short-Circuit Current and Fluid Transport Across Porcine Ciliary Epithelium.

    Science.gov (United States)

    Cheng, Angela King-Wah; Civan, Mortimer M; To, Chi-Ho; Do, Chi-Wai

    2016-12-01

    To investigate the effects of cAMP on transepithelial electrical parameters and fluid transport across porcine ciliary epithelium. Transepithelial electrical parameters were determined by mounting freshly isolated porcine ciliary epithelium in a modified Ussing chamber. Similarly, fluid movement across intact ciliary body was measured with a custom-made fluid flow chamber. Addition of 1, 10, and 100 μM 8-Br-cAMP (cAMP) to the aqueous side (nonpigmented ciliary epithelium, NPE) induced a sustained increase in short-circuit current (Isc). Addition of niflumic acid (NFA) to the aqueous surface effectively blocked the cAMP-induced Isc stimulation. The administration of cAMP to the stromal side (pigmented ciliary epithelium, PE) triggered a significant stimulation of Isc only at 100 μM. No additive effect was observed with bilateral application of cAMP. Likewise, forskolin caused a significant stimulation of Isc when applied to the aqueous side. Concomitantly, cAMP and forskolin increased fluid transport across porcine ciliary epithelium, and this stimulation was effectively inhibited by aqueous NFA. Depleting Cl- in the bathing solution abolished the baseline Isc and inhibited the subsequent stimulation by cAMP. Pretreatment with protein kinase A (PKA) blockers (H89/KT5720) significantly inhibited the cAMP- and forskolin-induced Isc responses. Our results suggest that cAMP triggers a sustained stimulation of Cl- and fluid transport across porcine ciliary epithelium; Cl- channels in the NPE cells are potentially a cellular site for this PKA-sensitive cAMP-mediated response.

  18. The Harvard Beat Assessment Test (H-BAT): a battery for assessing beat perception and production and their dissociation

    Science.gov (United States)

    Fujii, Shinya; Schlaug, Gottfried

    2013-01-01

    Humans have the abilities to perceive, produce, and synchronize with a musical beat, yet there are widespread individual differences. To investigate these abilities and to determine if a dissociation between beat perception and production exists, we developed the Harvard Beat Assessment Test (H-BAT), a new battery that assesses beat perception and production abilities. H-BAT consists of four subtests: (1) music tapping test (MTT), (2) beat saliency test (BST), (3) beat interval test (BIT), and (4) beat finding and interval test (BFIT). MTT measures the degree of tapping synchronization with the beat of music, whereas BST, BIT, and BFIT measure perception and production thresholds via psychophysical adaptive stair-case methods. We administered the H-BAT on thirty individuals and investigated the performance distribution across these individuals in each subtest. There was a wide distribution in individual abilities to tap in synchrony with the beat of music during the MTT. The degree of synchronization consistency was negatively correlated with thresholds in the BST, BIT, and BFIT: a lower degree of synchronization was associated with higher perception and production thresholds. H-BAT can be a useful tool in determining an individual's ability to perceive and produce a beat within a single session. PMID:24324421

  19. The Harvard Beat Assessment Test (H-BAT): a battery for assessing beat perception and production and their dissociation.

    Science.gov (United States)

    Fujii, Shinya; Schlaug, Gottfried

    2013-01-01

    Humans have the abilities to perceive, produce, and synchronize with a musical beat, yet there are widespread individual differences. To investigate these abilities and to determine if a dissociation between beat perception and production exists, we developed the Harvard Beat Assessment Test (H-BAT), a new battery that assesses beat perception and production abilities. H-BAT consists of four subtests: (1) music tapping test (MTT), (2) beat saliency test (BST), (3) beat interval test (BIT), and (4) beat finding and interval test (BFIT). MTT measures the degree of tapping synchronization with the beat of music, whereas BST, BIT, and BFIT measure perception and production thresholds via psychophysical adaptive stair-case methods. We administered the H-BAT on thirty individuals and investigated the performance distribution across these individuals in each subtest. There was a wide distribution in individual abilities to tap in synchrony with the beat of music during the MTT. The degree of synchronization consistency was negatively correlated with thresholds in the BST, BIT, and BFIT: a lower degree of synchronization was associated with higher perception and production thresholds. H-BAT can be a useful tool in determining an individual's ability to perceive and produce a beat within a single session.

  20. Elastohydrodynamic synchronization of adjacent beating flagella

    Science.gov (United States)

    Goldstein, Raymond E.; Lauga, Eric; Pesci, Adriana I.; Proctor, Michael R. E.

    2016-11-01

    It is now well established that nearby beating pairs of eukaryotic flagella or cilia typically synchronize in phase. A substantial body of evidence supports the hypothesis that hydrodynamic coupling between the active filaments, combined with waveform compliance, provides a robust mechanism for synchrony. This elastohydrodynamic mechanism has been incorporated into bead-spring models in which the beating flagella are represented by microspheres tethered by radial springs as they are driven about orbits by internal forces. While these low-dimensional models reproduce the phenomenon of synchrony, their parameters are not readily relatable to those of the filaments they represent. More realistic models, which reflect the underlying elasticity of the axonemes and the active force generation, take the form of fourth-order nonlinear partial differential equations (PDEs). While computational studies have shown the occurrence of synchrony, the effects of hydrodynamic coupling between nearby filaments governed by such continuum models have been examined theoretically only in the regime of interflagellar distances d large compared to flagellar length L . Yet in many biological situations d /L ≪1 . Here we present an asymptotic analysis of the hydrodynamic coupling between two extended filaments in the regime d /L ≪1 and find that the form of the coupling is independent of the microscopic details of the internal forces that govern the motion of the individual filaments. The analysis is analogous to that yielding the localized induction approximation for vortex filament motion, extended to the case of mutual induction. In order to understand how the elastohydrodynamic coupling mechanism leads to synchrony of extended objects, we introduce a heuristic model of flagellar beating. The model takes the form of a single fourth-order nonlinear PDE whose form is derived from symmetry considerations, the physics of elasticity, and the overdamped nature of the dynamics. Analytical

  1. Record low β beating in the LHC

    Directory of Open Access Journals (Sweden)

    R. Tomás

    2012-09-01

    Full Text Available The LHC is currently operating with a proton energy of 4 TeV and β^{*} functions at the ATLAS and CMS interaction points of 0.6 m. This is close to the design value at 7 TeV (β^{*}=0.55  m and represented a challenge for various aspects of the machine operation. In particular, a huge effort was put into the optics commissioning and an unprecedented peak β beating of around 7% was achieved in a high energy hadron collider.

  2. Role of spatial heterogeneity in the collective dynamics of cilia beating in a minimal one-dimensional model

    Science.gov (United States)

    Dey, Supravat; Massiera, Gladys; Pitard, Estelle

    2018-01-01

    Cilia are elastic hairlike protuberances of the cell membrane found in various unicellular organisms and in several tissues of most living organisms. In some tissues such as the airway tissues of the lung, the coordinated beating of cilia induces a fluid flow of crucial importance as it allows the continuous cleaning of our bronchia, known as mucociliary clearance. While most of the models addressing the question of collective dynamics and metachronal wave consider homogeneous carpets of cilia, experimental observations rather show that cilia clusters are heterogeneously distributed over the tissue surface. The purpose of this paper is to investigate the role of spatial heterogeneity on the coherent beating of cilia using a very simple one-dimensional model for cilia known as the rower model. We systematically study systems consisting of a few rowers to hundreds of rowers and we investigate the conditions for the emergence of collective beating. When considering a small number of rowers, a phase drift occurs, hence, a bifurcation in beating frequency is observed as the distance between rower clusters is changed. In the case of many rowers, a distribution of frequencies is observed. We found in particular the pattern of the patchy structure that shows the best robustness in collective beating behavior, as the density of cilia is varied over a wide range.

  3. Beats on the Table: Beat Writing in the Chicago Review and Big Table

    Directory of Open Access Journals (Sweden)

    Jaap van der Bent

    2012-07-01

    Full Text Available Normal 0 21 false false false NL X-NONE X-NONE MicrosoftInternetExplorer4 Kleine literaire tijdschriften, zogenaamde little magazines, hebben een belangrijke rol gespeeld bij de doorbraak, in de loop van de jaren vijftig, van de Amerikaanse Beat Generation. Aangezien grotere uitgeverijen en de gevestigde tijdschriften lange tijd terugschrokken voor de zowel inhoudelijk als formeel van de norm afwijkende uitingen van de Beats, verscheen hun werk aanvankelijk vooral in kleinere tijdschriften als de twee waaraan in dit artikel aandacht wordt besteed: de Chicago Review en Big Table. Aan de hand van een beschrijving van de inhoud van deze twee tijdschriften wordt geprobeerd duidelijk te maken hoe het werk van de Beat Generation zich in deze tijdschriften gaandeweg een eigen plaats verwierf. Speciale aandacht wordt besteed aan de rol van de redacteuren Irving Rosenthal en Paul Carroll; door zijn uitgekiende strategie om voor het omstreden werk van Beat-auteur William S. Burroughs geleidelijk een steeds grotere plaats in te ruimen, bepaalde vooral Rosenthal het veranderende karakter van de Chicago Review. De veranderingen bij dat tijdschrift verliepen niet zonder slag of stoot en waren voor de eigenaar ervan, de University of Chicago, op een gegeven moment aanleiding om de Chicago Review aan censuur te onderwerpen. Ook deze censuur en de reactie erop, de oprichting van Big Table, worden in het artikel belicht.

  4. Oxidative shift in tissue redox potential increases beat-to-beat variability of action potential duration.

    Science.gov (United States)

    Kistamás, Kornél; Hegyi, Bence; Váczi, Krisztina; Horváth, Balázs; Bányász, Tamás; Magyar, János; Szentandrássy, Norbert; Nánási, Péter P

    2015-07-01

    Profound changes in tissue redox potential occur in the heart under conditions of oxidative stress frequently associated with cardiac arrhythmias. Since beat-to-beat variability (short term variability, SV) of action potential duration (APD) is a good indicator of arrhythmia incidence, the aim of this work was to study the influence of redox changes on SV in isolated canine ventricular cardiomyocytes using a conventional microelectrode technique. The redox potential was shifted toward a reduced state using a reductive cocktail (containing dithiothreitol, glutathione, and ascorbic acid) while oxidative changes were initiated by superfusion with H2O2. Redox effects were evaluated as changes in "relative SV" determined by comparing SV changes with the concomitant APD changes. Exposure of myocytes to the reductive cocktail decreased SV significantly without any detectable effect on APD. Application of H2O2 increased both SV and APD, but the enhancement of SV was the greater, so relative SV increased. Longer exposure to H2O2 resulted in the development of early afterdepolarizations accompanied by tremendously increased SV. Pretreatment with the reductive cocktail prevented both elevation in relative SV and the development of afterdepolarizations. The results suggest that the increased beat-to-beat variability during an oxidative stress contributes to the generation of cardiac arrhythmias.

  5. Ciliary body toxicities of systemic oxcarbazepine and valproic acid treatments: electron microscopic study.

    Science.gov (United States)

    Göktaş, Güleser; Aktaş, Zeynep; Erdoğan, Deniz; Seymen, Cemile Merve; Karaca, Emine Esra; Cansu, Ali; Serdaroğlu, Ayşe; Kaplanoğlu, Gülnur Take

    2015-01-01

    Ciliary body is responsible for humour aqueous production in posterior chamber. Valproic acid (VPA) has been widely used for the treatment of epilepsy and other neuropsychiatric diseases such as bipolar disease and major depression. Oxcarbazepine (OXC) is a new anti-epileptic agent that has been used recently for childhood epilepsies such as VPA. In this study, we aimed to investigate the effects of VPA and OXC treatments used as antiepileptic in ciliary body by electron microscopy. In our study, 40 Wistar rats (21 days old) were divided equally into four groups which were applied saline (group 1), VPA (group 2), OXC (group 3) and VPA + OXC (group 4). The as-prepared ocular tissues were characterized by transmission electron microscopy (TEM) technique in scanning and transmission electron microscopy (SEM-TEM) (Carl Zeiss EVO LS10). The results confirmed that VPA caused dense ciliary body degeneration. Additionally, ciliary body degeneration in group 4 was supposed to be due to VPA treatment. Ciliary body damage and secondary outcomes should be considered in patients with long-term VPA therapy.

  6. Arf4 is required for Mammalian development but dispensable for ciliary assembly.

    Directory of Open Access Journals (Sweden)

    John A Follit

    2014-02-01

    Full Text Available The primary cilium is a sensory organelle, defects in which cause a wide range of human diseases including retinal degeneration, polycystic kidney disease and birth defects. The sensory functions of cilia require specific receptors to be targeted to the ciliary subdomain of the plasma membrane. Arf4 has been proposed to sort cargo destined for the cilium at the Golgi complex and deemed a key regulator of ciliary protein trafficking. In this work, we show that Arf4 binds to the ciliary targeting sequence (CTS of fibrocystin. Knockdown of Arf4 indicates that it is not absolutely required for trafficking of the fibrocystin CTS to cilia as steady-state CTS levels are unaffected. However, we did observe a delay in delivery of newly synthesized CTS from the Golgi complex to the cilium when Arf4 was reduced. Arf4 mutant mice are embryonic lethal and die at mid-gestation shortly after node formation. Nodal cilia appeared normal and functioned properly to break left-right symmetry in Arf4 mutant embryos. At this stage of development Arf4 expression is highest in the visceral endoderm but we did not detect cilia on these cells. In the visceral endoderm, the lack of Arf4 caused defects in cell structure and apical protein localization. This work suggests that while Arf4 is not required for ciliary assembly, it is important for the efficient transport of fibrocystin to cilia, and also plays critical roles in non-ciliary processes.

  7. Rapid diagnosis of primary ciliary dyskinesia: cell culture and soft computing analysis.

    Science.gov (United States)

    Pifferi, Massimo; Bush, Andrew; Montemurro, Francesca; Pioggia, Giovanni; Piras, Martina; Tartarisco, Gennaro; Di Cicco, Maria; Chinellato, Iolanda; Cangiotti, Angela M; Boner, Attilio L

    2013-04-01

    Diagnosis of primary ciliary dyskinesia (PCD) sometimes requires repeated nasal brushing to exclude secondary ciliary alterations. Our aim was to evaluate whether the use of a new method of nasal epithelial cell culture can speed PCD diagnosis in doubtful cases and to identify which are the most informative parameters by means of a multilayer artificial neural network (ANN). A cross-sectional study was performed in patients with suspected PCD. All patients underwent nasal brushing for ciliary motion analysis, ultrastructural assessment and evaluation of ciliary function after ciliogenesis in culture by ANN. 151 subjects were studied. A diagnostic suspension cell culture was obtained in 117 nasal brushings. A diagnosis of PCD was made in 36 subjects (29 of whom were children). In nine out of the 36 patients the diagnosis was made only after a second brushing, because of equivocal results of both tests at first examination. In each of these subjects diagnosis of PCD was confirmed by cell culture results. Cell culture in suspension evaluated by means of ANN allows the separation of PCD from secondary ciliary dyskinesia patients after only 5 days of culture and allows diagnosis to be reached in doubtful cases, thus avoiding the necessity of a second sample.

  8. Downstream collecting in ciliary suspension feeders: the catch-up principle

    DEFF Research Database (Denmark)

    Riisgård, Hans Ulrik; Nielsen, Claus; Larsen, Poul Scheel

    2000-01-01

    -size retention spectrum, the lower limit depends on spacing between cilia in phase, while the upper end depends on cilia length which may or may not allow particles to enter the ciliary region. On the basis of fluid mechanical considerations and literature descriptions of structure and function of the ciliary......Based on observations of feeding structures and currents in the polychaete Spirorbis tridentatus, the entoproct Loxosoma pectinaricola and the cycliophore Symbion pandora, which all possess compound cilia, it is hypothesized that their capture mechanism is based on the catch-up principle. According...... to this principle, the compound cilia constitute the pump which generates a flow with suspended particles that enters the ciliary region. In this region the same cilia, during their power stroke, catch up with suspended particles and transfer the particles to a food groove, or a mouth cavity. In the particle...

  9. Bacteriology and treatment of infections in the upper and lower airways in patients with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Alanin, Mikkel Christian

    2017-01-01

    The respiratory tract is lined with motile cilia that transport respiratory mucus. Primary ciliary dyskinesia (PCD) is a chronic genetic disease caused by mutations in genes responsible for ciliary structure and function. Non-functional airway cilia impair the mucociliary clearance (MCC), causing...

  10. Application of binaural beat phenomenon with aphasic patients.

    Science.gov (United States)

    Barr, D F; Mullin, T A; Herbert, P S

    1977-04-01

    We investigated whether six aphasics and six normal subjects could binaurally fuse two slightly differing frequencies of constant amplitude. The aphasics were subdivided into two groups: (1) two men who had had mild cerebrovascular accidents (CVAs) during the past 15 months; (2) four men who had had severe CVAs during the last 15 months. Two tones of different frequency levels but equal in intensity were presented dichotically to the subjects at 40 dB sensation level. All subjects had normal hearing at 500 Hz (0 to 25 dB). All six normal subjects and the two aphasics who had had mild CVAs could hear the binaural beats. The four aphasics who had had severe CVAs could not hear them. A 2 X 2 design resulting from this study was compared using chi2 test with Yates correction and was found to be significantly different (P less than .05). Two theories are presented to explain these findings: the "depression theory" and the "temporal time-sequencing theory." Therapeutic implications are also discussed relative to cerebral and/or brain stem involvement in the fusion of binaural stimuli.

  11. A novel ICK mutation causes ciliary disruption and lethal endocrine-cerebro-osteodysplasia syndrome.

    Science.gov (United States)

    Oud, Machteld M; Bonnard, Carine; Mans, Dorus A; Altunoglu, Umut; Tohari, Sumanty; Ng, Alvin Yu Jin; Eskin, Ascia; Lee, Hane; Rupar, C Anthony; de Wagenaar, Nathalie P; Wu, Ka Man; Lahiry, Piya; Pazour, Gregory J; Nelson, Stanley F; Hegele, Robert A; Roepman, Ronald; Kayserili, Hülya; Venkatesh, Byrappa; Siu, Victoria M; Reversade, Bruno; Arts, Heleen H

    2016-01-01

    Endocrine-cerebro-osteodysplasia (ECO) syndrome [MIM:612651] caused by a recessive mutation (p.R272Q) in Intestinal cell kinase (ICK) shows significant clinical overlap with ciliary disorders. Similarities are strongest between ECO syndrome, the Majewski and Mohr-Majewski short-rib thoracic dysplasia (SRTD) with polydactyly syndromes, and hydrolethalus syndrome. In this study, we present a novel homozygous ICK mutation in a fetus with ECO syndrome and compare the effect of this mutation with the previously reported ICK variant on ciliogenesis and cilium morphology. Through homozygosity mapping and whole-exome sequencing, we identified a second variant (c.358G > T; p.G120C) in ICK in a Turkish fetus presenting with ECO syndrome. In vitro studies of wild-type and mutant mRFP-ICK (p.G120C and p.R272Q) revealed that, in contrast to the wild-type protein that localizes along the ciliary axoneme and/or is present in the ciliary base, mutant proteins rather enrich in the ciliary tip. In addition, immunocytochemistry revealed a decreased number of cilia in ICK p.R272Q-affected cells. Through identification of a novel ICK mutation, we confirm that disruption of ICK causes ECO syndrome, which clinically overlaps with the spectrum of ciliopathies. Expression of ICK-mutated proteins result in an abnormal ciliary localization compared to wild-type protein. Primary fibroblasts derived from an individual with ECO syndrome display ciliogenesis defects. In aggregate, our findings are consistent with recent reports that show that ICK regulates ciliary biology in vitro and in mice, confirming that ECO syndrome is a severe ciliopathy.

  12. What makes a rhythm complex? The influence of musical training and accent type on beat perception.

    Science.gov (United States)

    Bouwer, Fleur L; Burgoyne, J Ashley; Odijk, Daan; Honing, Henkjan; Grahn, Jessica A

    2018-01-01

    Perception of a regular beat in music is inferred from different types of accents. For example, increases in loudness cause intensity accents, and the grouping of time intervals in a rhythm creates temporal accents. Accents are expected to occur on the beat: when accents are "missing" on the beat, the beat is more difficult to find. However, it is unclear whether accents occurring off the beat alter beat perception similarly to missing accents on the beat. Moreover, no one has examined whether intensity accents influence beat perception more or less strongly than temporal accents, nor how musical expertise affects sensitivity to each type of accent. In two experiments, we obtained ratings of difficulty in finding the beat in rhythms with either temporal or intensity accents, and which varied in the number of accents on the beat as well as the number of accents off the beat. In both experiments, the occurrence of accents on the beat facilitated beat detection more in musical experts than in musical novices. In addition, the number of accents on the beat affected beat finding more in rhythms with temporal accents than in rhythms with intensity accents. The effect of accents off the beat was much weaker than the effect of accents on the beat and appeared to depend on musical expertise, as well as on the number of accents on the beat: when many accents on the beat are missing, beat perception is quite difficult, and adding accents off the beat may not reduce beat perception further. Overall, the different types of accents were processed qualitatively differently, depending on musical expertise. Therefore, these findings indicate the importance of designing ecologically valid stimuli when testing beat perception in musical novices, who may need different types of accent information than musical experts to be able to find a beat. Furthermore, our findings stress the importance of carefully designing rhythms for social and clinical applications of beat perception, as not

  13. Long-term clearance from small airways in subjects with ciliary dysfunction

    OpenAIRE

    Hjelte Lena; Falk Rolf; Lindström Maria; Philipson Klas; Svartengren Magnus

    2006-01-01

    Abstract The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD) inhaled 111 Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasi...

  14. Experimental Observation of Chaotic Beats in Oscillators Sharing Nonlinearity

    Science.gov (United States)

    Paul Asir, M.; Jeevarekha, A.; Philominathan, P.

    This paper deals with the generation of chaotic beats in a system of two forced dissipative LCR oscillators sharing a nonlinear element. The presence of two external periodic excitations and a common nonlinear element in the chosen system enables the facile generation of chaotic beats. Thus rendered chaotic beats were characterized in both time domain and phase space. Lyapunov exponents and envelope of the beats were computed to diagnose the chaotic nature of the signals. The role of common nonlinearity on the complexity of the generated beats is discussed. Real-time experimental hardware implementation has also been done to confirm the subsistence of the phenomenon, for the first time. Extensive Multisim simulations were carried out to understand, a bit more about the shrinkage and revivals of state variables in phase space.

  15. Beating Social Democracy on Its Own Turf

    DEFF Research Database (Denmark)

    Arndt, Christoph

    2014-01-01

    -right parties to flourish in contexts where welfare issues have a natural salience as in the case of universal welfare states. In contrast, Scandinavian universal welfare states ought to benefit social democracy when it comes to issue voting on welfare issues. It is argued in this article that centre......-right parties can beat social democrats by credibly converging to its social democratic opponent on issues of universal welfare. Issue ownership voting to the benefit of centre-right parties will then be strongest among voters perceiving the centre-right to have converged to social democracy and perceiving...... the centre-right as issue-owner. Using Danish National Election Studies, 1998–2007, the article shows that the Danish Liberal Party outperformed the Social Democrats on traditional welfare issues among those voters perceiving the Liberals to be ideologically close to the social democrats. The findings help...

  16. Beat wave current drive experiment on DDT

    International Nuclear Information System (INIS)

    Hwang, D.Q.

    1991-03-01

    Several improvements have been made to the beat wave experiment this year. We are now able to vary the magnetic field over a much larger range, the plasma density is more uniform, and the electron temperature is significantly higher than last year (making it easier to couple energy from the electrostatic wave into the electron distribution). We have found evidence that at higher magnetic fields, ω ce /ω pe > 1, that numerous electrostatic modes are excited. This may be due to the fact that for a bounded plasma, ω pe is allowed (for small wave numbers). Although we are still not sure why the rvec k matching criteria (rvec k 0 = rvec k 1 + rvec k e ) is not more restrictive. A 35 GHz microwave scattering diagnostic has been designed, built, and tested in order to make a less perturbing measure of the electrostatic wave

  17. Terahertz radiation generation by beating of two laser beams in a collisional plasma with oblique magnetic field

    Science.gov (United States)

    Hematizadeh, Ayoob; Jazayeri, Seyed Masud; Ghafary, Bijan

    2018-02-01

    A scheme for excitation of terahertz (THz) radiation is presented by photo mixing of two super-Gaussian laser beams in a rippled density collisional magnetized plasma. Lasers having different frequencies and wave numbers but the same electric fields create a ponderomotive force on the electrons of plasma in the beating frequency. Super-Gaussian laser beam has the exclusive features such as steep gradient in laser intensity distribution, wider cross-section in comparison with Gaussian profiles, which make stronger ponderomotive force and higher THz radiation. The magnetic field is considered oblique to laser beams propagation direction; in this case, depending on the phase matching conditions different mode waves can propagate in plasma. It is found that amplitude and efficiency of the emitted THz radiation not only are sensitive to the beating frequency, collision frequency, and magnetic field strength but to the angle between laser beams and static magnetic field. The efficiency of THz radiation can be optimized in a certain angle.

  18. The impact of beat-to-beat variability in optimising the acute hemodynamic response in cardiac resynchronisation therapy

    Directory of Open Access Journals (Sweden)

    Steven Niederer

    2015-12-01

    Conclusion: The beat-to-beat variation in AHR is significant in the context of CRT cut off values. A LOS optimisation offers a novel index to identify the optimal pacing site that accounts for both the mean and variation of the baseline measurement and pacing protocol.

  19. Beating time: How ensemble musicians' cueing gestures communicate beat position and tempo.

    Science.gov (United States)

    Bishop, Laura; Goebl, Werner

    2018-01-01

    Ensemble musicians typically exchange visual cues to coordinate piece entrances. "Cueing-in" gestures indicate when to begin playing and at what tempo. This study investigated how timing information is encoded in musicians' cueing-in gestures. Gesture acceleration patterns were expected to indicate beat position, while gesture periodicity, duration, and peak gesture velocity were expected to indicate tempo. Same-instrument ensembles (e.g., piano-piano) were expected to synchronize more successfully than mixed-instrument ensembles (e.g., piano-violin). Duos performed short passages as their head and (for violinists) bowing hand movements were tracked with accelerometers and Kinect sensors. Performers alternated between leader/follower roles; leaders heard a tempo via headphones and cued their partner in nonverbally. Violin duos synchronized more successfully than either piano duos or piano-violin duos, possibly because violinists were more experienced in ensemble playing than pianists. Peak acceleration indicated beat position in leaders' head-nodding gestures. Gesture duration and periodicity in leaders' head and bowing hand gestures indicated tempo. The results show that the spatio-temporal characteristics of cueing-in gestures guide beat perception, enabling synchronization with visual gestures that follow a range of spatial trajectories.

  20. Prognostic Significance of Blood Pressure Variability on Beat-to-Beat Monitoring After Transient Ischemic Attack and Stroke.

    Science.gov (United States)

    Webb, Alastair J S; Mazzucco, Sara; Li, Linxin; Rothwell, Peter M

    2018-01-01

    Visit-to-visit and day-to-day blood pressure (BP) variability (BPV) predict an increased risk of cardiovascular events but only reflect 1 form of BPV. Beat-to-beat BPV can be rapidly assessed and might also be predictive. In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (Oxford Vascular Study), BPV (coefficient of variation) was measured beat-to-beat for 5 minutes (Finometer), day-to-day for 1 week on home monitoring (3 readings, 3× daily), and on awake ambulatory BP monitoring. BPV after 1-month standard treatment was related (Cox proportional hazards) to recurrent stroke and cardiovascular events for 2 to 5 years, adjusted for mean systolic BP. Among 520 patients, 26 had inadequate beat-to-beat recordings, and 22 patients were in atrial fibrillation. Four hundred five patients had all forms of monitoring. Beat-to-beat BPV predicted recurrent stroke and cardiovascular events independently of mean systolic BP (hazard ratio per group SD, stroke: 1.47 [1.12-1.91]; P =0.005; cardiovascular events: 1.41 [1.08-1.83]; P =0.01), including after adjustment for age and sex (stroke: 1.47 [1.12-1.92]; P =0.005) and all risk factors (1.40 [1.00-1.94]; P =0.047). Day-to-day BPV was less strongly associated with stroke (adjusted hazard ratio, 1.29 [0.97-1.71]; P =0.08) but similarly with cardiovascular events (1.41 [1.09-1.83]; P =0.009). BPV on awake ambulatory BP monitoring was nonpredictive (stroke: 0.89 [0.59-1.35]; P =0.59; cardiovascular events: 1.08 [0.77-1.52]; P =0.65). Despite a weak correlation ( r =0.119; P =0.02), beat-to-beat BPV was associated with risk of recurrent stroke independently of day-to-day BPV (1.41 [1.05-1.90]; P =0.02). Beat-to-beat BPV predicted recurrent stroke and cardiovascular events, independently of mean systolic BP and risk factors but short-term BPV on ambulatory BP monitoring did not. Beat-to-beat BPV may be a useful additional marker of cardiovascular risk. © 2017 The Authors.

  1. Mutations in LCA5, encoding the ciliary protein lebercilin, cause Leber congenital amaurosis.

    NARCIS (Netherlands)

    Hollander, A.I. den; Koenekoop, R.K.; Mohamed, M.D.; Arts, H.H.; Boldt, K.; Towns, K.V.; Sedmak, T.; Beer, M. de; Nagel-Wolfrum, K.; McKibbin, M.; Dharmaraj, S.; Lopez, I.; Ivings, L.; Williams, G.A.; Springell, K.; Woods, C.G.; Jafri, H.; Rashid, Y.; Strom, T.M.; Zwaag, B. van der; Gosens, I.; Kersten, F.F.J.; Wijk, E. van; Veltman, J.A.; Zonneveld, M.N.; Beersum, S.E.C. van; Maumenee, I.H.; Wolfrum, U.; Cheetham, M.E.; Ueffing, M.; Cremers, F.P.M.; Inglehearn, C.F.; Roepman, R.

    2007-01-01

    Leber congenital amaurosis (LCA) causes blindness or severe visual impairment at or within a few months of birth. Here we show, using homozygosity mapping, that the LCA5 gene on chromosome 6q14, which encodes the previously unknown ciliary protein lebercilin, is associated with this disease. We

  2. A longitudinal evaluation of hearing and ventilation tube insertion in patients with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Andersen, Tobias Nicolai; Alanin, Mikkel Christian; von Buchwald, Christian

    2016-01-01

    INTRODUCTION: Primary ciliary dyskinesia (PCD) is an autosomal recessive genetic disease, which primarily manifests with oto-sino-pulmonary symptoms. Otitis media with effusion (OME) is common from early childhood. The existing literature on OME management in PCD is conflicting. The goals of the ...

  3. ZMYND10 is mutated in primary ciliary dyskinesia and interacts with LRRC6

    DEFF Research Database (Denmark)

    Zariwala, Maimoona A; Gee, Heon Yung; Kurkowiak, Małgorzata

    2013-01-01

    Defects of motile cilia cause primary ciliary dyskinesia (PCD), characterized by recurrent respiratory infections and male infertility. Using whole-exome resequencing and high-throughput mutation analysis, we identified recessive biallelic mutations in ZMYND10 in 14 families and mutations in the ...

  4. Target recognition and synapse formation by ciliary-ganglion neurons in tissue culture

    NARCIS (Netherlands)

    Stevens, W.F.; Slaaf, D.W.; Hooisma, J.; Magchielse, T.; Meeter, E.

    1978-01-01

    A less complicated source of neurons suitable for this type of studies is the parasympathetic ciliary ganglion. In the pigeon and in the chick this ganglion is known to contain only two classes of neurons, both of which are cholinoceptive and cholinergic and that innervate the muscle fibres of the

  5. Multicenter analysis of body mass index, lung function, and sputum microbiology in primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Maglione, Marco; Bush, Andrew; Nielsen, Kim G

    2014-01-01

    BACKGROUND: No studies longitudinally, simultaneously assessed body mass index (BMI) and spirometry in primary ciliary dyskinesia (PCD). METHODS: We determined BMI and spirometry in 158 PCD children and adolescents from London, UK (n = 75), Naples, Italy (n = 23) and Copenhagen, Denmark (n = 60) ...

  6. Gene Expression and Functional Annotation of the Human Ciliary Body Epithelia

    NARCIS (Netherlands)

    Janssen, Sarah F.; Gorgels, Theo G. M. F.; Bossers, Koen; ten Brink, Jacoline B.; Essing, Anke H. W.; Nagtegaal, Martijn; van der Spek, Peter J.; Jansonius, Nomdo M.; Bergen, Arthur A. B.

    2012-01-01

    Purpose: The ciliary body (CB) of the human eye consists of the non-pigmented (NPE) and pigmented (PE) neuro-epithelia. We investigated the gene expression of NPE and PE, to shed light on the molecular mechanisms underlying the most important functions of the CB. We also developed molecular

  7. Bug22 influences cilium morphology and the post-translational modification of ciliary microtubules

    Directory of Open Access Journals (Sweden)

    Teresa Mendes Maia

    2014-01-01

    Cilia and flagella are organelles essential for motility and sensing of environmental stimuli. Depending on the cell type, cilia acquire a defined set of functions and, accordingly, are built with an appropriate length and molecular composition. Several ciliary proteins display a high degree of conservation throughout evolution and mutations in ciliary genes are associated with various diseases such as ciliopathies and infertility. Here, we describe the role of the highly conserved ciliary protein, Bug22, in Drosophila. Previous studies in unicellular organisms have shown that Bug22 is required for proper cilia function, but its exact role in ciliogenesis has not been investigated yet. Null Bug22 mutant flies display cilia-associated phenotypes and nervous system defects. Furthermore, sperm differentiation is blocked at the individualization stage, due to impaired migration of the individualization machinery. Tubulin post-translational modifications (PTMs such as polyglycylation, polyglutamylation or acetylation, are determinants of microtubule (MT functions and stability in centrioles, cilia and neurons. We found defects in the timely incorporation of polyglycylation in sperm axonemal MTs of Bug22 mutants. In addition, we found that depletion of human Bug22 in RPE1 cells resulted in the appearance of longer cilia and reduced axonemal polyglutamylation. Our work identifies Bug22 as a protein that plays a conserved role in the regulation of PTMs of the ciliary axoneme.

  8. Growth of the crabgrass species Digitaria ciliaris and Digitaria nuda Crescimento das espécies de capim-colchão Digitaria ciliaris e Digitaria nuda

    Directory of Open Access Journals (Sweden)

    R.C. Souza

    2012-06-01

    Full Text Available The aim of this research paper was to compare the growth of D. ciliaris and D. nuda crabgrass species under non-competitive conditions. To this end, two experiments were conducted, one from March - July 2010 and the other from February - June 2011. The experimental design of both trials was completely randomized making a factorial (2 seasons x 2 species crabgrass x 12 evaluation periods with four replications. Assessments began at 15 days after sowing (DAS, and repeated weekly until 92 DAS. The variables evaluated were total dry matter (roots+leaves+stems, leaf area, leaf number and tiller. The results were submitted to analysis of variance and the absolute growth rate, relative growth rate and leaf area ratio were calculated using the means, which were adjusted regression models. The crabgrass species were significantly different in leaf area, leaf number, tiller number and dry matter per plant. D. ciliaris for all variables was statistically higher than D. nuda. Regarding the speed at which the growth of the species occurred, the absolute growth rate and relative growth rate of D. ciliaris was also greater than D. nuda. In addition, D. ciliaris also had a lower leaf area ratio indicating greater efficiency in converting light energy into carbohydrates. It can be concluded that D. ciliaris has a higher growth rate in conditions where there is no limitation of nutrients and water availability in relation to D. nuda, mainly due to D. ciliaris have greater leaf area, number of leaves and dry matter accumulation per plant.O objetivo da presente pesquisa foi comparar o crescimento das espécies de capim colchão D. ciliaris e D. nuda, em condições não-competitivas. Para isso, foram conduzidos dois experimentos, um de março a julho de 2010 e outro de fevereiro a junho de 2011. O delineamento experimental de ambos os ensaios foi inteiramente casualizado, perfazendo um esquema fatorial (2 épocas x 2 espécies de capim colchão x 12 períodos de

  9. Mathematical modelling of pressure-driven micropolar biological flow due to metachronal wave propulsion of beating cilia.

    Science.gov (United States)

    Akbar, N S; Tripathi, D; Khan, Z H; Bég, O Anwar

    2018-04-06

    In this paper, we present an analytical study of pressure-driven flow of micropolar non-Newtonian physiological fluids through a channel comprising two parallel oscillating walls. The cilia are arranged at equal intervals and protrude normally from both walls of the infinitely long channel. A metachronal wave is generated due to natural beating of cilia and the direction of wave propagation is parallel to the direction of fluid flow. Appropriate expressions are presented for deformation via longitudinal and transverse velocity components induced by the ciliary beating phenomenon with cilia assumed to follow elliptic trajectories. The conservation equations for mass, longitudinal and transverse (linear) momentum and angular momentum are reduced in accordance with the long wavelength and creeping Stokesian flow approximations and then normalized with appropriate transformations. The resulting non-linear moving boundary value problem is solved analytically for constant micro-inertia density, subject to physically realistic boundary conditions. Closed-form expressions are derived for axial velocity, angular velocity, volumetric flow rate and pressure rise. The transport phenomena are shown to be dictated by several non-Newtonian parameters, including micropolar material parameter and Eringen coupling parameter, and also several geometric parameters, viz eccentricity parameter, wave number and cilia length. The influence of these parameters on streamline profiles (with a view to addressing trapping features via bolus formation and evolution), pressure gradient and other characteristics are evaluated graphically. Both axial and angular velocities are observed to be substantially modified with both micropolar rheological parameters and furthermore are significantly altered with increasing volumetric flow rate. Free pumping is also examined. An inverse relationship between pressure rise and flow rate is computed which is similar to that observed in Newtonian fluids. The

  10. Regulation of anterior chamber drainage by bicarbonate-sensitive soluble adenylyl cyclase in the ciliary body.

    Science.gov (United States)

    Lee, Yong S; Tresguerres, Martin; Hess, Kenneth; Marmorstein, Lihua Y; Levin, Lonny R; Buck, Jochen; Marmorstein, Alan D

    2011-12-02

    Glaucoma is a leading cause of blindness affecting as many as 2.2 million Americans. All current glaucoma treatment strategies aim to reduce intraocular pressure (IOP). IOP results from the resistance to drainage of aqueous humor (AH) produced by the ciliary body in a process requiring bicarbonate. Once secreted into the anterior chamber, AH drains from the eye via two pathways: uveoscleral and pressure-dependent or conventional outflow (C(t)). Modulation of "inflow" and "outflow" pathways is thought to occur via distinct, local mechanisms. Mice deficient in the bicarbonate channel bestrophin-2 (Best2), however, exhibit a lower IOP despite an increase in AH production. Best2 is expressed uniquely in nonpigmented ciliary epithelial (NPE) cells providing evidence for a bicarbonate-dependent communicative pathway linking inflow and outflow. Here, we show that bicarbonate-sensitive soluble adenylyl cyclase (sAC) is highly expressed in the ciliary body in NPE cells, but appears to be absent from drainage tissues. Pharmacologic inhibition of sAC in mice causes a significant increase in IOP due to a decrease in C(t) with no effect on inflow. In mice deficient in sAC IOP is elevated, and C(t) is decreased relative to wild-type mice. Pharmacologic inhibition of sAC did not alter IOP or C(t) in sAC-deficient mice. Based on these data we propose that the ciliary body can regulate C(t) and that sAC serves as a critical sensor of bicarbonate in the ciliary body regulating the secretion of substances into the AH that govern outflow facility independent of pressure.

  11. Tuning-in to the beat: Aesthetic appreciation of musical rhythms correlates with a premotor activity boost.

    Science.gov (United States)

    Kornysheva, Katja; von Cramon, D Yves; Jacobsen, Thomas; Schubotz, Ricarda I

    2010-01-01

    Listening to music can induce us to tune in to its beat. Previous neuroimaging studies have shown that the motor system becomes involved in perceptual rhythm and timing tasks in general, as well as during preference-related responses to music. However, the role of preferred rhythm and, in particular, of preferred beat frequency (tempo) in driving activity in the motor system remains unknown. The goals of the present functional magnetic resonance imaging (fMRI) study were to determine whether the musical rhythms that are subjectively judged as beautiful boost activity in motor-related areas and if so, whether this effect is driven by preferred tempo, the underlying pulse people tune in to. On the basis of the subjects' judgments, individual preferences were determined for the different systematically varied constituents of the musical rhythms. Results demonstrate the involvement of premotor and cerebellar areas during preferred compared to not preferred musical rhythms and indicate that activity in the ventral premotor cortex (PMv) is enhanced by preferred tempo. Our findings support the assumption that the premotor activity increase during preferred tempo is the result of enhanced sensorimotor simulation of the beat frequency. This may serve as a mechanism that facilitates the tuning-in to the beat of appealing music. 2009 Wiley-Liss, Inc.

  12. "'Jackin’ for Beats'": DJing for Citation Critique

    Directory of Open Access Journals (Sweden)

    Todd Craig

    2013-10-01

    Full Text Available A challenge in teaching English composition is helping students envision plagiarism as “borrowing” – showing love to author(s and/or text(s that further their argument(s, versus “stealing” – biting someone’s style and words. Alastair Pennycook (1996 and Sarah Wakefield (2006 have contributed pieces to the elaborate plagiarism/citation puzzle, while Houston Baker situated the hip-hop DJ in seminal text Black Studies, Rap and the Academy (1993. Merging these moments introduces critical questions: Did Diddy invent “the remix” or become the illest beat-biter ever? How did DJ/Producers Pete Rock and Large Professor pay homage to previous musical genres to further hip-hop remix production without just taking 4-8 bar samples, copying sources and claiming unethical ownership? And how can this discussion provide students a window into citation conversations? This article will remix these “texts” to introduce the idea of DJ Rhetoric to discuss plagiarism. Through the lens of the hip-hop DJ in writing classrooms, one can foster an appreciation of the difference between “love and theft” in student citation. This article will couple examples from hip-hop music/culture while simultaneously remixing interviews from various hip-hop DJ/producers to help answer these difficult questions.

  13. Sympathetic neurons modulate the beat rate of pluripotent cell-derived cardiomyocytes in vitro.

    Science.gov (United States)

    Takeuchi, Akimasa; Shimba, Kenta; Mori, Masahide; Takayama, Yuzo; Moriguchi, Hiroyuki; Kotani, Kiyoshi; Lee, Jong-Kook; Noshiro, Makoto; Jimbo, Yasuhiko

    2012-12-01

    Although stem cell-derived cardiomyocytes have great potential for the therapy of heart failure, it is unclear whether their function after grafting can be controlled by the host sympathetic nervous system, a component of the autonomic nervous system (ANS). Here we demonstrate the formation of functional connections between rat sympathetic superior cervical ganglion (SCG) neurons and pluripotent (P19.CL6) cell-derived cardiomyocytes (P19CMs) in compartmentalized co-culture, achieved using photolithographic microfabrication techniques. Formation of synapses between sympathetic neurons and P19CMs was confirmed by immunostaining with antibodies against β-3 tubulin, synapsin I and cardiac troponin-I. Changes in the beat rate of P19CMs were triggered after electrical stimulation of the co-cultured SCG neurons, and were affected by the pulse frequency of the electrical stimulation. Such changes in the beat rate were prevented when propranolol, a β-adrenoreceptor antagonist, was added to the culture medium. These results suggest that the beat rate of differentiated cardiomyocytes can be modulated by electrical stimulation of connected sympathetic neurons.

  14. Brain responses to 40-Hz binaural beat and effects on emotion and memory.

    Science.gov (United States)

    Jirakittayakorn, Nantawachara; Wongsawat, Yodchanan

    2017-10-01

    Gamma oscillation plays a role in binding process or sensory integration, a process by which several brain areas beside primary cortex are activated for higher perception of the received stimulus. Beta oscillation is also involved in interpreting received stimulus and occurs following gamma oscillation, and this process is known as gamma-to-beta transition, a process for neglecting unnecessary stimuli in surrounding environment. Gamma oscillation also associates with cognitive functions, memory and emotion. Therefore, modulation of the brain activity can lead to manipulation of cognitive functions. The stimulus used in this study was 40-Hz binaural beat because binaural beat induces frequency following response. This study aimed to investigate the neural oscillation responding to the 40-Hz binaural beat and to evaluate working memory function and emotional states after listening to that stimulus. Two experiments were developed based on the study aims. In the first experiment, electroencephalograms were recorded while participants listened to the stimulus for 30min. The results suggested that frontal, temporal, and central regions were activated within 15min. In the second experiment, word list recall task was conducted before and after listening to the stimulus for 20min. The results showed that, after listening, the recalled words were increase in the working memory portion of the list. Brunel Mood Scale, a questionnaire to evaluate emotional states, revealed changes in emotional states after listening to the stimulus. The emotional results suggested that these changes were consistent with the induced neural oscillations. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Patient-specific three-dimensional explant spheroids derived from human nasal airway epithelium

    DEFF Research Database (Denmark)

    Marthin, June Kehlet; Stevens, Elizabeth Munkebjerg; Larsen, Lars Allan

    2017-01-01

    BACKGROUND: Three-dimensional explant spheroid formation is an ex vivo technique previously used in studies of airway epithelial ion and water transport. Explanted cells and sheets of nasal epithelium form fully differentiated spheroids enclosing a partly fluid-filled lumen with the ciliated apical...... surface facing the outside and accessible for analysis of ciliary function. METHODS: We performed a two-group comparison study of ciliary beat pattern and ciliary beat frequency in spheroids derived from nasal airway epithelium in patients with primary ciliary dyskinesia (PCD) and in healthy controls...... in the investigation of pathophysiological aspects and drug effects in human nasal airway epithelium....

  16. Keep the Beat Recipes | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... the Beat Recipes: Deliciously Healthy Dinners. The new cookbook features 75 simple and delicious recipes influenced by ... nhlbi.nih.gov/files/docs/public/heart/Dinners_Cookbook_508-compliant.pdf . Fall 2011 Issue: Volume 6 ...

  17. Human induced pluripotent stem cell-derived beating cardiac tissues on paper.

    Science.gov (United States)

    Wang, Li; Xu, Cong; Zhu, Yujuan; Yu, Yue; Sun, Ning; Zhang, Xiaoqing; Feng, Ke; Qin, Jianhua

    2015-11-21

    There is a growing interest in using paper as a biomaterial scaffold for cell-based applications. In this study, we made the first attempt to fabricate a paper-based array for the culture, proliferation, and direct differentiation of human induced pluripotent stem cells (hiPSCs) into functional beating cardiac tissues and create "a beating heart on paper." This array was simply constructed by binding a cured multi-well polydimethylsiloxane (PDMS) mold with common, commercially available paper substrates. Three types of paper material (print paper, chromatography paper and nitrocellulose membrane) were tested for adhesion, proliferation and differentiation of human-derived iPSCs. We found that hiPSCs grew well on these paper substrates, presenting a three-dimensional (3D)-like morphology with a pluripotent property. The direct differentiation of human iPSCs into functional cardiac tissues on paper was also achieved using our modified differentiation approach. The cardiac tissue retained its functional activities on the coated print paper and chromatography paper with a beating frequency of 40-70 beats per min for up to three months. Interestingly, human iPSCs could be differentiated into retinal pigment epithelium on nitrocellulose membrane under the conditions of cardiac-specific induction, indicating the potential roles of material properties and mechanical cues that are involved in regulating stem cell differentiation. Taken together, these results suggest that different grades of paper could offer great opportunities as bioactive, low-cost, and 3D in vitro platforms for stem cell-based high-throughput drug testing at the tissue/organ level and for tissue engineering applications.

  18. Does training with beat gestures favour children's narrative discourse abilities?

    OpenAIRE

    Vilà Giménez, Ingrid

    2016-01-01

    There is consensus evidence that gestures and prosody are important precursors of children’s early language abilities and development. Previous literature has investigated the beneficial role of beat gestures in the recall of information by preschoolers (Igualada, Esteve-Gibert, & Prieto, under review; Austin & Sweller, 2014). However, to our knowledge, little is known about whether the use of beat gestures can promote children’s later linguistic abilities and specifically whether training wi...

  19. Beat gestures and prosodic prominence: impact on learning

    OpenAIRE

    Kushch, Olga

    2018-01-01

    Previous research has shown that gestures are beneficial for language learning. This doctoral thesis centers on the effects of beat gestures– i.e., hand and arm gestures that are typically associated with prosodically prominent positions in speech - on such processes. Little is known about how the two central properties of beat gestures, namely how they mark both information focus and rhythmic positions in speech, can be beneficial for learning either a first or a second language. The main go...

  20. Beat gestures help preschoolers recall and comprehend discourse information.

    Science.gov (United States)

    Llanes-Coromina, Judith; Vilà-Giménez, Ingrid; Kushch, Olga; Borràs-Comes, Joan; Prieto, Pilar

    2018-08-01

    Although the positive effects of iconic gestures on word recall and comprehension by children have been clearly established, less is known about the benefits of beat gestures (rhythmic hand/arm movements produced together with prominent prosody). This study investigated (a) whether beat gestures combined with prosodic information help children recall contrastively focused words as well as information related to those words in a child-directed discourse (Experiment 1) and (b) whether the presence of beat gestures helps children comprehend a narrative discourse (Experiment 2). In Experiment 1, 51 4-year-olds were exposed to a total of three short stories with contrastive words presented in three conditions, namely with prominence in both speech and gesture, prominence in speech only, and nonprominent speech. Results of a recall task showed that (a) children remembered more words when exposed to prominence in both speech and gesture than in either of the other two conditions and that (b) children were more likely to remember information related to those words when the words were associated with beat gestures. In Experiment 2, 55 5- and 6-year-olds were presented with six narratives with target items either produced with prosodic prominence but no beat gestures or produced with both prosodic prominence and beat gestures. Results of a comprehension task demonstrated that stories told with beat gestures were comprehended better by children. Together, these results constitute evidence that beat gestures help preschoolers not only to recall discourse information but also to comprehend it. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Deep learning based beat event detection in action movie franchises

    Science.gov (United States)

    Ejaz, N.; Khan, U. A.; Martínez-del-Amor, M. A.; Sparenberg, H.

    2018-04-01

    Automatic understanding and interpretation of movies can be used in a variety of ways to semantically manage the massive volumes of movies data. "Action Movie Franchises" dataset is a collection of twenty Hollywood action movies from five famous franchises with ground truth annotations at shot and beat level of each movie. In this dataset, the annotations are provided for eleven semantic beat categories. In this work, we propose a deep learning based method to classify shots and beat-events on this dataset. The training dataset for each of the eleven beat categories is developed and then a Convolution Neural Network is trained. After finding the shot boundaries, key frames are extracted for each shot and then three classification labels are assigned to each key frame. The classification labels for each of the key frames in a particular shot are then used to assign a unique label to each shot. A simple sliding window based method is then used to group adjacent shots having the same label in order to find a particular beat event. The results of beat event classification are presented based on criteria of precision, recall, and F-measure. The results are compared with the existing technique and significant improvements are recorded.

  2. Effect of cAMP on short-circuit current in isolated human ciliary body.

    Science.gov (United States)

    Wu, Ren-yi; Ma, Ning; Hu, Qian-qian

    2013-07-01

    Cyclic adenosine monophosphate (cAMP) could activate chloride channels in bovine ciliary body and trigger an increase in the ionic current (short-circuit current, Isc) across the ciliary processes in pigs. The purpose of this study was to investigate how cAMP modulates Isc in isolated human ciliary processes and the possible involvement of chloride transport across the tissue in cAMP-induced Isc change. In an Ussing-type chamber system, the Isc changes induced by the cAMP analogue 8-bromo-cAMP and an adenylyl cyclase activator forskolin in isolated human ciliary processes were assessed. The involvement of Cl(-) component in the bath solution was investigated. The effect of Cl(-) channel (10 µmol/L niflumic acid and 1 mmol/L 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS)), K(+) channel (10 mmol/L tetraethylammonium chloride (TEA)), or Na(+) channel blockers (1 mmol/L amiloride) on 8-bromo-cAMP-induced Isc change was also studied. Dose-dependently, 8-bromo-cAMP (10 nmol/L-30 µmol/L) or forskolin (10 nmol/L-3 µmol/L) increased Isc across the ciliary processes with an increase in negative potential difference on the non-pigmented epithelium (NPE) side of the tissue. Isc increase induced by 8-bromo-cAMP was more pronounced when the drug was applied on the NPE side than on the pigmented epithelium side. When the tissue was bathed in low Cl(-) solutions, the Isc increase was significantly inhibited. Finally, niflumic acid and DIDS, but not TEA or amiloride, significantly prevented the Isc increase induced by 8-bromo-cAMP. cAMP stimulates stroma-to-aqueous anionic transport in isolated human ciliary processes. Chloride is likely to be among the ions, the transportation of which across the tissue is triggered by cAMP, suggesting the potential role of cAMP in the process of aqueous humor formation in human eyes.

  3. Beat-to-beat assessment of left ventricular ejection in atrial fibrillation

    Energy Technology Data Exchange (ETDEWEB)

    Benjelloun, H; Brochier, M; Itti, R; Philippe, L; Lorgeron, J M

    1983-05-01

    Beat-to-beat left ventricular ejection was evaluated in a group of 20 patients with chronic atrial fibrillation using a computerized single probe detector. The reference group consisted of 10 patients with sinus rhythm. For each patient 30 successive cardiac cycles were analyzed and the relative variations of four parameters were assessed: R-R interval, diastolic and systolic time intervals, and ejection amplitude, corresponding to the left ventricular stroke volume. The mean variations were respectively 3.4%, 10.4%, 8.4%, and 11.8% in patients with sinus rhythm, and 21.9%, 37.9%, 10.6% and 30.5% in patients with artrial fibrillation. This demonstrates that changes in ejection are mainly related to the duration of the filling phase, with nearly constant systolic times. Correlations between R-R intervals and systolic ejection amplitudes were highly significant (P<0.001) in patients with atrial fibrillation in 85% of cases. This information complements the average ejection fraction obtained from multiple cycle superimposition.

  4. Beat-to-beat assessment of left ventricular ejection in atrial fibrillation

    International Nuclear Information System (INIS)

    Benjelloun, H.; Brochier, M.; Itti, R.; Philippe, L.; Lorgeron, J.M.

    1983-01-01

    Beat-to-beat left ventricular ejection was evaluated in a group of 20 patients with chronic atrial fibrillation using a computerized single probe detector. The reference group consisted of 10 patients with sinus rhythm. For each patient 30 successive cardiac cycles were analyzed and the relative variations of four parameters were assessed: R-R interval, diastolic and systolic time intervals, and ejection amplitude, corresponding to the left ventricular stroke volume. The mean variations were respectively 3.4%, 10.4%, 8.4%, and 11.8% in patients with sinus rhythm, and 21.9%, 37.9%, 10.6% and 30.5% in patients with artrial fibrillation. This demonstrates that changes in ejection are mainly related to the duration of the filling phase, with nearly constant systolic times. Correlations between R-R intervals and systolic ejection amplitudes were highly significant (P<0.001) in patients with atrial fibrillation in 85% of cases. This information complements the average ejection fraction obtained from multiple cycle superimposition. (orig.)

  5. Beat-to-beat evaluation of left ventricular ejection in cardiac arrhythmias

    International Nuclear Information System (INIS)

    Itti, R.; Philippe, L.; Lorgeron, J.M.

    1982-01-01

    Conventional multi-gated cardiac blood pool studies suffer from two kinds of superimpositions: the spatial overlapping of various heart chambers and the temporal superimposition of a large number of cardiac cycles. The first problem can be partially solved by first pass techniques or by emission tomography. For the second one, which is specially critical arrhythmias, the single probe device (''nuclear stethoscope'') represents an original solution. Patients with normal cardiac rythm and patients presenting various kinds of cardiac rythm alterations were examined using a commercial ''nuclear stethoscope''. Some characteristic results achieved in these cases, were presented. For blood pool labeling, 20 mCi of 99mTc albumin was injected. The single probe detector was then positioned over the left ventricular area. The beat-to-beat left ventricular activity curve was then recorded for several minutes on paper in the same time as the E.C.G. signal. In cases with irregular cardiac rythm, the multigated techniques yield an average value of left ventricular ejection. Due to the relatively constant duration of systole, the superimposition of cycles may be valid during contration: differences mainly appear during diastole. But, as it could be demonstrated using the ''nuclear stethoscope'', individual cycles can show a large variability of ejection and average ejection fraction is only a very partial aspect of the real cardiac function

  6. Electrocardiogram: his bundle potentials can be recorded noninvasively beat by beat on surface electrocardiogram.

    Science.gov (United States)

    Wang, Gaopin; Liu, Renguang; Chang, Qinghua; Xu, Zhaolong; Zhang, Yingjie; Pan, Dianzhu

    2017-03-15

    The micro waveform of His bundle potential can't be recorded beat-to-beat on surface electrocardiogram yet. We have found that the micro-wavelets before QRS complex may be related to atrioventricular conduction system potentials. This study is to explore the possibility of His bundle potential can be noninvasively recorded on surface electrocardiogram. We randomized 65 patients undergoing radiofrequency catheter ablation of paroxysmal superventricular tachycardia (exclude overt Wolff-Parkinson-White syndrome) to receive "conventional electrocardiogram" and "new electrocardiogram" before the procedure. His bundle electrogram was collected during the procedure. Comparative analysis of PA s (PA interval recorded on surface electrocardiogram), AH s (AH interval recorded on surface electrocardiogram) and HV s (HV interval recorded on surface electrocardiogram) interval recorded on surface "new electrocardiogram" and PA, AH, HV interval recorded on His bundle electrogram was investigated. There was no difference (P > 0.05) between groups in HV s interval (49.63 ± 6.19 ms) and HV interval (49.35 ± 6.49 ms). Results of correlational analysis found that HV S interval was significantly positively associated with HV interval (r = 0.929; P electrocardiogram. Noninvasive His bundle potential tracing might represent a new method for locating the site of atrioventricular block and identifying the origin of a wide QRS complex.

  7. Beat-to-beat variability of cardiac action potential duration: underlying mechanism and clinical implications.

    Science.gov (United States)

    Nánási, Péter P; Magyar, János; Varró, András; Ördög, Balázs

    2017-10-01

    Beat-to-beat variability of cardiac action potential duration (short-term variability, SV) is a common feature of various cardiac preparations, including the human heart. Although it is believed to be one of the best arrhythmia predictors, the underlying mechanisms are not fully understood at present. The magnitude of SV is basically determined by the intensity of cell-to-cell coupling in multicellular preparations and by the duration of the action potential (APD). To compensate for the APD-dependent nature of SV, the concept of relative SV (RSV) has been introduced by normalizing the changes of SV to the concomitant changes in APD. RSV is reduced by I Ca , I Kr , and I Ks while increased by I Na , suggesting that ion currents involved in the negative feedback regulation of APD tend to keep RSV at a low level. RSV is also influenced by intracellular calcium concentration and tissue redox potential. The clinical implications of APD variability is discussed in detail.

  8. Beat-to-beat variability of QT intervals is increased in patients with drug-induced long-QT syndrome

    DEFF Research Database (Denmark)

    Hinterseer, Martin; Thomsen, Morten Bækgaard; Beckmann, Britt-Maria

    2008-01-01

    Torsades de pointes arrhythmias (TdP) occur by definition in the setting of prolonged QT intervals. Animal models of drug induced Long-QT syndrome (dLQTS) have shown higher predictive value for proarrhythmia with beat-to-beat variability of repolarization duration (BVR) when compared with QT inte...... intervals. Here, we evaluate variability of QT intervals in patients with a history of drug-induced long QT syndrome (dLQTS) and TdP in absence of a mutation in any of the major LQTS genes.......Torsades de pointes arrhythmias (TdP) occur by definition in the setting of prolonged QT intervals. Animal models of drug induced Long-QT syndrome (dLQTS) have shown higher predictive value for proarrhythmia with beat-to-beat variability of repolarization duration (BVR) when compared with QT...

  9. Protein Interaction Analysis Provides a Map of the Spatial and Temporal Organization of the Ciliary Gating Zone.

    Science.gov (United States)

    Takao, Daisuke; Wang, Liang; Boss, Allison; Verhey, Kristen J

    2017-08-07

    The motility and signaling functions of the primary cilium require a unique protein and lipid composition that is determined by gating mechanisms localized at the base of the cilium. Several protein complexes localize to the gating zone and may regulate ciliary protein composition; however, the mechanisms of ciliary gating and the dynamics of the gating components are largely unknown. Here, we used the BiFC (bimolecular fluorescence complementation) assay and report for the first time on the protein-protein interactions that occur between ciliary gating components and transiting cargoes during ciliary entry. We find that the nucleoporin Nup62 and the C termini of the nephronophthisis (NPHP) proteins NPHP4 and NPHP5 interact with the axoneme-associated kinesin-2 motor KIF17 and thus spatially map to the inner region of the ciliary gating zone. Nup62 and NPHP4 exhibit rapid turnover at the transition zone and thus define dynamic components of the gate. We find that B9D1, AHI1, and the N termini of NPHP4 and NPHP5 interact with the transmembrane protein SSTR3 and thus spatially map to the outer region of the ciliary gating zone. B9D1, AHI1, and NPHP5 exhibit little to no turnover at the transition zone and thus define components of a stable gating structure. These data provide the first comprehensive map of the molecular orientations of gating zone components along the inner-to-outer axis of the ciliary gating zone. These results advance our understanding of the functional roles of gating zone components in regulating ciliary protein composition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Phase dispersion of Raman and Rayleigh-enhanced four-wave mixings in femtosecond polarization beats

    International Nuclear Information System (INIS)

    Yan, Zhao; Zhi-Qiang, Nie; Chang-Biao, Li; Yan-Peng, Zhang; Chen-Li, Gan; Huai-Bin, Zheng; Yuan-Yuan, Li; Ke-Qing, Lu

    2009-01-01

    Based on color-locking noisy field correlation in three Markovian stochastic models, phase dispersions of the Raman- and Rayleigh-enhanced four-wave mixing (FWM) have been investigated. The phase dispersions are modified by both linewidth and time delay for negative time delay, but only by linewidth for positive time delay. Moreover, the results under narrowband condition are close to the nonmodified nonlinear dispersion and absorption of the material. Homodyne and heterodyne detections of the Raman, the Rayleigh and the mixing femtosecond difference-frequency polarization beats have also been investigated, separately

  11. A polarization-division multiplexing SSB-OFDM system with beat interference cancellation receivers

    Science.gov (United States)

    Yang, Peiling; Ma, Jianxin; Zhang, Junyi

    2018-06-01

    In this paper, we have proposed a polarization-division multiplexing (PDM) single-sideband optical orthogonal frequency division multiplexing (SSB-OOFDM) scheme with signal-signal beat interference cancellation receivers with balanced detection (ICRBD). This system can double channel capacity and improve spectrum efficiency (SE) with the reduced guard band (GB) due to the PDM. Multiple input multiple output (MIMO) technique is used to solve polarization mode dispersion (PMD) associated with channel estimation and equalization. By simulation, we demonstrate the efficacy of the proposed technique for a 2 ×40 Gbit/s 16-QAM SSB-PDM-OOFDM system according to the error vector magnitude (EVM) and the constellation diagrams.

  12. Adaptive control with self-tuning for non-invasive beat-by-beat blood pressure measurement.

    Science.gov (United States)

    Nogawa, Masamichi; Ogawa, Mitsuhiro; Yamakoshi, Takehiro; Tanaka, Shinobu; Yamakoshi, Ken-ichi

    2011-01-01

    Up to now, we have successfully carried out the non-invasive beat-by-beat measurement of blood pressure (BP) in the root of finger, superficial temporal and radial artery based on the volume-compensation technique with reasonable accuracy. The present study concerns with improvement of control method for this beat-by-beat BP measurement. The measurement system mainly consists of a partial pressurization cuff with a pair of LED and photo-diode for the detection of arterial blood volume, and a digital self-tuning control method. Using healthy subjects, the performance and accuracy of this system were evaluated through comparison experiments with the system using a conventional empirically tuned PID controller. The significant differences of BP measured in finger artery were not showed in systolic (SBP), p=0.52, and diastolic BP (DBP), p=0.35. With the advantage of the adaptive control with self-tuning method, which can tune the control parameters without disturbing the control system, the application area of the non-invasive beat-by-beat measurement method will be broadened.

  13. LEFT-VENTRICULAR BEAT-TO-BEAT PERFORMANCE IN ATRIAL-FIBRILLATION - CONTRIBUTION OF FRANK-STARLING MECHANISM AFTER SHORT RATHER THAN LONG RR INTERVALS

    NARCIS (Netherlands)

    GOSSELINK, ATM; BLANKSMA, PK; CRIJNS, HJGM; VANGELDER, IC; DEKAM, PJ; HILLEGE, HL; NIEMEIJER, MG; LIE, KI; MEIJLER, FL

    1995-01-01

    Objectives. This study sought to evaluate control mechanisms of the varying left ventricular performance in atrial fibrillation. Background. Atrial fibrillation is characterized by a randomly irregular ventricular response, resulting in continuous variation in left ventricular beat-to-beat

  14. Left ventricular beat-to-beat performance in atrial fibrillation: Contribution of Frank-Starling mechanism after short rather than long intervals

    NARCIS (Netherlands)

    Gosselink, A.T.M.; Blanksma, P.K.; Crijns, H.J.G.M.; Gelder, I.C. van; Kam, P.J. de; Hillege, H.L.; Niemeijer, M.G.; Lie, K.I.; Meijler, F.L.

    1995-01-01

    This study sought to evaluate control mechanisms of the varying left ventricular performance in atrial fibrillation. Atrial fibrillation is characterized by a randomly irregular ventricular response, resulting in continuous variation in left ventricular beat-to-beat mechanical behavior and

  15. Longitudinal study of lung function in a cohort of primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Ellerman, A; Bisgaard, H

    1997-01-01

    Patients with primary ciliary dyskinesia (PCD) have pronounced stasis of their respiratory secretions and therefore recurrent lower airway infections, which raises concerns for the development of lung function. Twenty four patients with PCD have been studied prospectively with a standardized regime...... patients entering as children (forced vital capacity (FVC) 70 versus 85% predicted; forced expiratory volume in one second (FEV1) 59 versus 72% pred). The lung damage did not relate to the type of ciliary dyskinesia. During the subsequent surveillance of the groups for a median of 14 and 7 yrs...... in our clinic for 2-16 yrs with clinic visits, including spirometry 2-4 times per year, daily physiotherapy and monthly sputum cultures with subsequent specific antibiotic treatment. Lung function was significantly lower in the 12 PCD patients entering the cohort as adults when compared to the PCD...

  16. Ultrastructural alterations in ciliary cells exposed to ionizing radiation. A scanning and transmission electron microscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Baldetorp, L; Mecklenburg, C v; Haakansson, C H [Lund Univ. (Sweden). Hospital; Lund Univ. (Sweden). Dept. of Zoology)

    1977-01-01

    Early effects of ionizing radiation were investigated in an experimental in vitro system using the ciliary cells of the tracheal mucous membrane of the rabbit, irradiated at 30/sup 0/C and at more than 90% humidity. The changes in physiological activities of the ciliary cells caused by irradation were continously registered during the irradation. The specimens were examined immediately after irradiation electron microscopically. The morphological changes in irradiated material after 10-70 Gy are compared with normal material. After 40-70 Gy, scanning electron microscopy revealed the formation of vesicles on cilia, and club-like protrusions and adhesion of their tips. After 30-70 Gy, a swelling of mitochondrial membranes and cristae was apparent transmission electron microscopically. The membrane alterations caused by irradiation are assumed to disturb the permeability and flow of ATP from the mitochondria, which in turn leads to the recorded changes in the activity of the ciliated cells.

  17. Species variation in biology and physiology of the ciliary epithelium: similarities and differences.

    Science.gov (United States)

    Do, Chi Wai; Civan, Mortimer M

    2009-04-01

    Glaucoma is a leading cause of irreversible blindness worldwide. Lowering intraocular pressure (IOP) is the only strategy documented to delay the appearance and retard the progression of vision loss. One major approach for lowering IOP is to slow the rate of aqueous humor formation by the ciliary epithelium. As discussed in the present review, the transport basis for this secretion is largely understood. However, several substantive issues are yet to be resolved, including the integrated regulation of secretion, the functional topography of the ciliary epithelium, and the degree and significance of species variation in aqueous humor inflow. This review discusses species differences in net secretion, particularly of Cl(-) and HCO(3)(-) secretion. Identifying animal models most accurately mimicking aqueous humor formation in the human will facilitate development of future novel initiatives to lower IOP.

  18. Continued administration of ciliary neurotrophic factor protects mice from inflammatory pathology in experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Kuhlmann, Tanja; Remington, Leah; Cognet, Isabelle

    2006-01-01

    Multiple sclerosis is an inflammatory disease of the central nervous system that leads to loss of myelin and oligodendrocytes and damage to axons. We show that daily administration (days 8 to 24) of murine ciliary neurotrophic factor (CNTF), a neurotrophic factor that has been described as a surv......Multiple sclerosis is an inflammatory disease of the central nervous system that leads to loss of myelin and oligodendrocytes and damage to axons. We show that daily administration (days 8 to 24) of murine ciliary neurotrophic factor (CNTF), a neurotrophic factor that has been described...... it was withdrawn. After cessation of CNTF treatment, inflammation and symptoms returned to control levels. However, slight but significantly higher numbers of oligodendrocytes, NG2-positive cells, axons, and neurons were observed in mice that had been treated with high concentrations of CNTF. Our results show...

  19. Impact of the Smoothened inhibitor, IPI-926, on smoothened ciliary localization and Hedgehog pathway activity.

    Directory of Open Access Journals (Sweden)

    Marisa O Peluso

    Full Text Available A requisite step for canonical Hedgehog (Hh pathway activation by Sonic Hedgehog (Shh ligand is accumulation of Smoothened (Smo to the primary cilium (PC. Activation of the Hh pathway has been implicated in a broad range of cancers, and several Smo antagonists are being assessed clinically, one of which is approved for the treatment of advanced basal cell carcinoma. Recent reports demonstrate that various Smo antagonists differentially impact Smo localization to the PC while still exerting inhibitory activity. In contrast to other synthetic small molecule Smo antagonists, the natural product cyclopamine binds to and promotes ciliary accumulation of Smo and "primes" cells for Hh pathway hyper-responsiveness after compound withdrawal. We compared the properties of IPI-926, a semi-synthetic cyclopamine analog, to cyclopamine with regard to potency, ciliary Smo accumulation, and Hh pathway activity after compound withdrawal. Like cyclopamine, IPI-926 promoted accumulation of Smo to the PC. However, in contrast to cyclopamine, IPI-926 treatment did not prime cells for hyper-responsiveness to Shh stimulation after compound withdrawal, but instead demonstrated continuous inhibition of signaling. By comparing the levels of drug-induced ciliary Smo accumulation with the degree of Hh pathway activity after compound withdrawal, we propose that a critical threshold of ciliary Smo is necessary for "priming" activity to occur. This "priming" appears achievable with cyclopamine, but not IPI-926, and is cell-line dependent. Additionally, IPI-926 activity was evaluated in a murine tumor xenograft model and a pharmacokinetic/pharmacodynamic relationship was examined to assess for in vivo evidence of Hh pathway hyper-responsiveness. Plasma concentrations of IPI-926 correlated with the degree and duration of Hh pathway suppression, and pathway activity did not exceed baseline levels out to 96 hours post dose. The overall findings suggest that IPI-926 possesses

  20. STOCHASTIC SIMULATION FOR BUFFELGRASS (Cenchrus ciliaris L.) PASTURES IN MARIN, N. L., MEXICO

    OpenAIRE

    José Romualdo Martínez-López; Erasmo Gutierrez-Ornelas; Miguel Angel Barrera-Silva; Rafael Retes-López

    2014-01-01

    A stochastic simulation model was constructed to determine the response of net primary production of buffelgrass (Cenchrus ciliaris L.) and its dry matter intake by cattle, in Marín, NL, México. Buffelgrass is very important for extensive livestock industry in arid and semiarid areas of northeastern Mexico. To evaluate the behavior of the model by comparing the model results with those reported in the literature was the objective in this experiment. Model simulates the monthly production of...

  1. Bug22p, a Conserved Centrosomal/Ciliary Protein Also Present in Higher Plants, Is Required for an Effective Ciliary Stroke in Paramecium ▿ †

    Science.gov (United States)

    Laligné, C.; Klotz, C.; Garreau de Loubresse, N.; Lemullois, M.; Hori, M.; Laurent, F. X.; Papon, J. F.; Louis, B.; Cohen, J.; Koll, F.

    2010-01-01

    Centrioles, cilia, and flagella are ancestral conserved organelles of eukaryotic cells. Among the proteins identified in the proteomics of ciliary proteins in Paramecium, we focus here on a protein, Bug22p, previously detected by cilia and basal-body high-throughput studies but never analyzed per se. Remarkably, this protein is also present in plants, which lack centrioles and cilia. Bug22p sequence alignments revealed consensus positions that distinguish species with centrioles/cilia from plants. In Paramecium, antibody and green fluorescent protein (GFP) fusion labeling localized Bug22p in basal bodies and cilia, and electron microscopy immunolabeling refined the localization to the terminal plate of the basal bodies, the transition zone, and spots along the axoneme, preferentially between the membrane and the microtubules. RNA interference (RNAi) depletion of Bug22p provoked a strong decrease in swimming speed, followed by cell death after a few days. High-speed video microscopy and morphological analysis of Bug22p-depleted cells showed that the protein plays an important role in the efficiency of ciliary movement by participating in the stroke shape and rigidity of cilia. The defects in cell swimming and growth provoked by RNAi can be complemented by expression of human Bug22p. This is the first reported case of complementation by a human gene in a ciliate. PMID:20118210

  2. Bug22p, a conserved centrosomal/ciliary protein also present in higher plants, is required for an effective ciliary stroke in Paramecium.

    Science.gov (United States)

    Laligné, C; Klotz, C; de Loubresse, N Garreau; Lemullois, M; Hori, M; Laurent, F X; Papon, J F; Louis, B; Cohen, J; Koll, F

    2010-04-01

    Centrioles, cilia, and flagella are ancestral conserved organelles of eukaryotic cells. Among the proteins identified in the proteomics of ciliary proteins in Paramecium, we focus here on a protein, Bug22p, previously detected by cilia and basal-body high-throughput studies but never analyzed per se. Remarkably, this protein is also present in plants, which lack centrioles and cilia. Bug22p sequence alignments revealed consensus positions that distinguish species with centrioles/cilia from plants. In Paramecium, antibody and green fluorescent protein (GFP) fusion labeling localized Bug22p in basal bodies and cilia, and electron microscopy immunolabeling refined the localization to the terminal plate of the basal bodies, the transition zone, and spots along the axoneme, preferentially between the membrane and the microtubules. RNA interference (RNAi) depletion of Bug22p provoked a strong decrease in swimming speed, followed by cell death after a few days. High-speed video microscopy and morphological analysis of Bug22p-depleted cells showed that the protein plays an important role in the efficiency of ciliary movement by participating in the stroke shape and rigidity of cilia. The defects in cell swimming and growth provoked by RNAi can be complemented by expression of human Bug22p. This is the first reported case of complementation by a human gene in a ciliate.

  3. Loss and gain of cone types in vertebrate ciliary photoreceptor evolution.

    Science.gov (United States)

    Musser, Jacob M; Arendt, Detlev

    2017-11-01

    Ciliary photoreceptors are a diverse cell type family that comprises the rods and cones of the retina and other related cell types such as pineal photoreceptors. Ciliary photoreceptor evolution has been dynamic during vertebrate evolution with numerous gains and losses of opsin and phototransduction genes, and changes in their expression. For example, early mammals lost all but two cone opsins, indicating loss of cone receptor types in response to nocturnal lifestyle. Our review focuses on the comparison of specifying transcription factors and cell type-specific transcriptome data in vertebrate retinae to build and test hypotheses on ciliary photoreceptor evolution. Regarding cones, recent data reveal that a combination of factors specific for long-wavelength sensitive opsin (Lws)- cones in non-mammalian vertebrates (Thrb and Rxrg) is found across all differentiating cone photoreceptors in mice. This suggests that mammalian ancestors lost all but one ancestral cone type, the Lws-cone. We test this hypothesis by a correlation analysis of cone transcriptomes in mouse and chick, and find that, indeed, transcriptomes of all mouse cones are most highly correlated to avian Lws-cones. These findings underscore the importance of specifying transcription factors in tracking cell type evolution, and shed new light on the mechanisms of cell type loss and gain in retina evolution. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Comparative responses of the Savanna grasses Cenchrus ciliaris and Themeda triandra to defoliation.

    Science.gov (United States)

    Hodgkinson, K C; Ludlow, M M; Mott, J J; Baruch, Z

    1989-04-01

    Two perennial tussock grasses of savannas were compared in a glasshouse study to determine why they differed in their ability to withstand frequent, heavy grazing; Cenchrus ciliaris is tolerant and Themeda triandra is intolerant of heavy grazing. Frequent defoliation at weekly intervals for six weeks reduced shoot biomass production over a subsequent 42 day regrowth period compared with previously undefoliated plants (infrequent) in T. triandra, but not in C. ciliaris. Leaf area of T. triandra expanded rapidly following defoliation but high initial relative growth rates of shoots were not sustained after 14 days of regrowth because of reducing light utilising efficiency of leaves. Frequently defoliated plants were slower in rate of leaf area expansion and this was associated with reduced photosynthetic capacity of newly formed leaves, lower allocation of photosynthate to leaves but not lower tiller numbers. T. triandra appears well adapted to a regime where defoliation is sufficiently infrequent to allow carbon to be fixed to replace that used in initial leaf area expansion. In contrast, C. ciliaris is better adapted to frequent defoliation than is T. triandra, because horizontally orientated nodal tillers are produced below the defoliation level. This morphological adaptation resulted in a 10-fold higher leaf area remaining after defoliation compared with similarly defoliated T. triandra, which together with the maintenance of moderate levels of light utilising efficiency, contributed to the higher leaf area and shoot weight throughout the regrowth period.

  5. HEATR2 plays a conserved role in assembly of the ciliary motile apparatus.

    Directory of Open Access Journals (Sweden)

    Christine P Diggle

    2014-09-01

    Full Text Available Cilia are highly conserved microtubule-based structures that perform a variety of sensory and motility functions during development and adult homeostasis. In humans, defects specifically affecting motile cilia lead to chronic airway infections, infertility and laterality defects in the genetically heterogeneous disorder Primary Ciliary Dyskinesia (PCD. Using the comparatively simple Drosophila system, in which mechanosensory neurons possess modified motile cilia, we employed a recently elucidated cilia transcriptional RFX-FOX code to identify novel PCD candidate genes. Here, we report characterization of CG31320/HEATR2, which plays a conserved critical role in forming the axonemal dynein arms required for ciliary motility in both flies and humans. Inner and outer arm dyneins are absent from axonemes of CG31320 mutant flies and from PCD individuals with a novel splice-acceptor HEATR2 mutation. Functional conservation of closely arranged RFX-FOX binding sites upstream of HEATR2 orthologues may drive higher cytoplasmic expression of HEATR2 during early motile ciliogenesis. Immunoprecipitation reveals HEATR2 interacts with DNAI2, but not HSP70 or HSP90, distinguishing it from the client/chaperone functions described for other cytoplasmic proteins required for dynein arm assembly such as DNAAF1-4. These data implicate CG31320/HEATR2 in a growing intracellular pre-assembly and transport network that is necessary to deliver functional dynein machinery to the ciliary compartment for integration into the motile axoneme.

  6. Long-term clearance from small airways in subjects with ciliary dysfunction

    Directory of Open Access Journals (Sweden)

    Hjelte Lena

    2006-05-01

    Full Text Available Abstract The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD inhaled 111 Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasions up to 21 days after inhalation. Results were compared with data from ten healthy controls. For additional comparison three of the PCD subjects also inhaled the test particles with normal inhalation flow, 0.5 L/s, providing a more central deposition. The lung retention at 24 h in % of lung deposition (Ret24 was higher (p 24 with slow inhalation flow was 73.9 ± 1.9 % compared to 68.9 ± 7.5 % with normal inhalation flow in the three PCD subjects exposed twice. During day 7–21 the three PCD subjects exposed twice cleared 9 % with normal flow, probably representing predominantly alveolar clearance, compared to 19 % with slow inhalation flow, probably representing mainly small airway clearance. This study shows that despite ciliary dysfunction, clearance continues in the small airways beyond 24 h. There are apparently additional clearance mechanisms present in the small airways.

  7. Palladium-103 plaque radiation therapy for ciliary body melanoma through a functioning glaucoma filtering bleb.

    Science.gov (United States)

    Pathan, Arif H K; Barash, Alexander; Tena, Lawrence B; Finger, Paul T

    2018-01-01

    To provide a clinical description of the long-term outcome of a 103 Pd plaque-irradiated ciliary body melanoma with extrascleral extension while attempting to preserve a subadjacent glaucoma filtering bleb. A 75-year-old woman with pseudoexfoliative glaucoma for 17 years, 16 years status post argon laser trabeculoplasty, and 15 years status post trabeculectomy in the left eye, was diagnosed with an ipsilateral ciliary body melanoma with visible extrascleral extension. Treatment involved insertion of a 103 Pd radioactive plaque over the functioning trabeculectomy, with removal 7 days later. At plaque insertion, amniotic membrane grafts were used to cover the plaque and protect the filtering site. The tumor was successfully treated without clinical evidence of harm to the filtering bleb, with resultant stable intraocular pressure. However, the patient developed blebitis 1.5 years later. Though it resolved with topical antibiotic therapy, the bleb became less succulent. Two years postoperatively, she developed a spontaneous hyphema that resolved after one injection of transscleral bevacizumab 1.25 mg. Her tumor continually regressed in thickness. Without additional glaucoma surgery, her intraocular pressure remained well-controlled on topical medications for 6 years. Ciliary body melanoma with minimal extrascleral extension beneath a functioning filtering bleb can be treated using radioactive plaque therapy. In this case, we were able to achieve both tumor regression and glaucoma control by covering the plaque with an amniotic membrane graft.

  8. Primary ciliary dyskinesia: a report from ATS 2001, May 18–23, San Francisco

    Directory of Open Access Journals (Sweden)

    Noone Peadar G

    2001-06-01

    Full Text Available Abstract Primary ciliary dyskinesia (PCD is a genetic disorder of abnormal ciliary structure and function that leads to defective mucociliary clearance, resulting in oto-sino-pulmonary disease, and infertility. The disease is currently under intense investigation by a number of research groups worldwide. At the recent American Thoracic Society meeting in San Francisco in May 2001, two sessions focused on PCD; a symposium session on May 21 with several featured expert speakers was followed by a mini-symposium on Tuesday May 22, with one featured speaker and presentation of nine abstracts covering a range of research topics. Mattias Salathe (University of Miami, USA and Stephen Brody (Washington University, St Louis, USA chaired the symposium session. Presentations focused on the clinical spectrum of PCD, the genetics of PCD, a proteomics approach to detail the structure of cilia, the role of cilia in the embryology of situs laterality, and airway epithelial cell biology. The mini-symposium was chaired by Peadar Noone (University of North Carolina, USA and Malcolm King (University of Alberta, USA and included presentations on the use of PCD as a human disease model, accurate definition of the phenotype using clinical and cell biologic markers, and molecular studies. The latter reports ranged from isolation of a protein involved in ciliary structure and function to genetic studies using linkage analysis and the candidate gene approach. Clinicians and scientists alike displayed considerable interest at both sessions, and there were several lively question–answer sessions.

  9. Adenoid ciliostimulation in children with chronic otitis media.

    Science.gov (United States)

    Andreoli, Steven M; Schlosser, Rodney J; Wang, Ling-Feng; Mulligan, Ryan M; Discolo, Christopher M; White, David R

    2013-01-01

    Adenoid hypertrophy and chronic adenoiditis are associated with an increased incidence of chronic otitis media. This study intends to determine the relationship between chronic otitis media and dynamic ciliary beat frequency in children undergoing adenoidectomy. Prospective, controlled study. Pediatric tertiary care hospital. Children undergoing adenoidectomy were enrolled. Patients were stratified according to their indication for surgery, including adenotonsillar hypertrophy with obstructive sleep apnea, chronic otitis media with effusion, or recurrent episodes of acute otitis media. Adenoids were harvested using the curette. Tissue was sectioned and allowed to equilibrate in basal media for 24 hours. Cilia-bearing tissue was then stimulated using isoproterenol or methacholine. Ciliary beat frequency was serially reordered and analyzed using the Sisson-Ammons Video Analysis software program. Baseline ciliary beat frequency was similar in all groups (N = 47, total). Using isoproterenol, children with chronic otitis media with effusion demonstrated a blunted dynamic ciliary response at 2 and 3 hours relative to control (P = .0176 and P = .0282). Methacholine-stimulated ciliary beat frequency was not different between each group. At 2 and 3 hours following isoproterenol stimulation, there was a significant blunting of dynamic ciliary beat frequency in children with chronic otitis media with effusion. This ciliary dysfunction may provide a physiological explanation related to chronic adenoiditis in children with chronic otitis media.

  10. SRS-A leukotrienes decrease the activity of human respiratory cilia

    DEFF Research Database (Denmark)

    Bisgaard, H; Pedersen, M

    1987-01-01

    We have studied the effects of the slow reacting substance of anaphylaxis (SRS-A) constituents leukotrienes (LT) C4 and D4 on the ciliary activity of human respiratory cells. The ciliary beat frequency on human nasal cells harvested by cell scraping from the inferior turbinate was measured...

  11. Some nonlinear processes relevant to the beat wave accelerator

    International Nuclear Information System (INIS)

    Bingham, R.; Mori, W.B.

    1985-03-01

    The beat wave accelerator depends on the generation of a large amplitude plasma wave with a phase velocity close to the velocity of light c. The plasma wave (ωsub(p), ksub(p)) is generated by beating colinear laser beams (ω 1 , k 1 ) and (ω 2 ,k 2 ) with ωsub(p) = ω 1 -ω 2 , ksub(p) = k 1 -k 2 . Since the process involves both large amplitude transverse and longitudinal waves, various nonlinear instabilities associated with either wave may occur. The object of the article is to discuss some of the processes that may compete with the beat wave generation listing their threshold and growth rate. (author)

  12. Continuing studies of the plasma beat wave accelerator

    International Nuclear Information System (INIS)

    Joshi, C.

    1990-01-01

    This is a proposal for the release of third year funds for the ''Plasma Beat Wave Accelerator'' program (PBWA) at UCLA under the direction of Professor C. Joshi. This report is also a summary of progress on this project since March 1990; i.e., the date of the last report to the DOE. Once again we note that although the program is for historical reasons called the Plasma Beat Wave Accelerator Program, our group is active in all areas of applications of lasers and plasmas in future high energy accelerators. These are as follows: heat gradient plasma structures; excited by plasma beat wave technique; laser wake field technique; and plasma wake field technique. Development of a photoinjector-driven, 20 MeV linac; and theoretical studies of the plasma lens and use of plasmas at the final focus

  13. Phase velocity of nonlinear plasma waves in the laser beat-wave accelerator

    International Nuclear Information System (INIS)

    Spence, W.L.

    1985-01-01

    The suggested plasma-laser accelerator is an attempt to achieve a very high energy gradient by resonantly exciting a longitudinal wave traveling at close to the speed of light in cold plasma by means of the beat-wave generated by the transverse fields in two laser beams. Previous calculations to all orders in v/sub z/ have been done essentially from the laboratory frame point of view and have treated the plasma wave as having sharply defined phase velocity equal to the speed of light. However a high energy particle beam undergoing acceleration sees the plasma wave from a nearly light-like frame of reference and hence is very sensitive to small deviations in its phase velocity. Here the authors introduce a calculational scheme that includes all orders in v/sub z/ and in the plasma density, and additionally takes into account the influence of plasma nonlinearities on the wave's phase velocity. The main assumption is that the laser frequencies are very large compared to the plasma frequency - under which they are able to in essence formally sum up all orders of forward Raman scattering. They find that the nonlinear plasma wave does not have simply a single phase velocity - it is really a superposition of many - but that the beat-wave which drives it is usefully described by a non-local effective phase velocity function

  14. High frequency ultrasound imaging in pupillary block glaucoma.

    Science.gov (United States)

    Aslanides, I M; Libre, P E; Silverman, R H; Reinstein, D Z; Lazzaro, D R; Rondeau, M J; Harmon, G K; Coleman, D J

    1995-01-01

    BACKGROUND--The diagnosis of pupillary block glaucoma requires sufficient clarity of the ocular media. This is particularly important for assessment of both the presence and patency of an iridotomy, and the determination of central anterior chamber depth. METHODS--High frequency ultrasonography was used in three patients with suspected pupillary block to determine iris configuration, posterior chamber volume, and ciliary body conformation. RESULTS--All patients demonstrated high frequency ultrasonographic findings consistent with pupillary block: iris bombé, a formed posterior chamber, and a lack of anterior rotation of the ciliary processes. CONCLUSION--High frequency ultrasound imaging appears to be a valuable adjunct in making or corroborating the diagnosis of pupillary block glaucoma. Images PMID:8534666

  15. Justification of Wife Beating in Adolescents: Associated Beliefs and Behaviors.

    Science.gov (United States)

    Devenish, Bethany; Hooley, Merrilyn; Mellor, David

    2018-04-01

    Socioeconomically disadvantaged adolescents who are exposed to social norms related to violence against women are more likely to experience or be perpetrators of intimate partner violence. This study evaluated factors hypothesized to be associated with acceptance of wife beating among 240 male and female adolescents aged 10-16 years participating in a World Vision program in Armenia. Acceptance of wife beating was associated with relational victimization, perceived social support, and parent and community boundaries and expectations, but was not associated with overt victimization or aggression. These findings highlight several areas that may be important for violence prevention research.

  16. A model-based Bayesian framework for ECG beat segmentation

    International Nuclear Information System (INIS)

    Sayadi, O; Shamsollahi, M B

    2009-01-01

    The study of electrocardiogram (ECG) waveform amplitudes, timings and patterns has been the subject of intense research, for it provides a deep insight into the diagnostic features of the heart's functionality. In some recent works, a Bayesian filtering paradigm has been proposed for denoising and compression of ECG signals. In this paper, it is shown that this framework may be effectively used for ECG beat segmentation and extraction of fiducial points. Analytic expressions for the determination of points and intervals are derived and evaluated on various real ECG signals. Simulation results show that the method can contribute to and enhance the clinical ECG beat segmentation performance

  17. Use of binaural beat tapes for treatment of anxiety: a pilot study of tape preference and outcomes.

    Science.gov (United States)

    Le Scouarnec, R P; Poirier, R M; Owens, J E; Gauthier, J; Taylor, A G; Foresman, P A

    2001-01-01

    Recent studies and anecdotal reports suggest that binaural auditory beats can affect mood, performance on vigilance tasks, and anxiety. To determine whether mildly anxious people would report decreased anxiety after listening daily for 1 month to tapes imbedded with tones that create binaural beats, and whether they would show a definite tape preference among 3 tapes. A 1-group pre-posttest pilot study. Patients' homes. A volunteer sample of 15 mildly anxious patients seen in the Clinique Psyché, Montreal, Quebec. Participants were asked to listen at least 5 times weekly for 4 weeks to 1 or more of 3 music tapes containing tones that produce binaural beats in the electroencephalogram delta/theta frequency range. Participants also were asked to record tape usage, tape preference, and anxiety ratings in a journal before and after listening to the tape or tapes. Anxiety ratings before and after tape listening, pre- and post-study State-Trait Anxiety Inventory scores, and tape preferences documented in daily journals. Listening to the binaural beat tapes resulted in a significant reduction in the anxiety score reported daily in patients' diaries. The number of times participants listened to the tapes in 4 weeks ranged from 10 to 17 (an average of 1.4 to 2.4 times per week) for approximately 30 minutes per session. End-of-study tape preferences indicated that slightly more participants preferred tape B, with its pronounced and extended patterns of binaural beats, over tapes A and C. Changes in pre- and posttest listening State-Trait Anxiety Inventory scores trended toward a reduction of anxiety, but these differences were not statistically significant. Listening to binaural beat tapes in the delta/theta electroencephalogram range may be beneficial in reducing mild anxiety. Future studies should account for music preference among participants and include age as a factor in outcomes, incentives to foster tape listening, and a physiologic measure of anxiety reduction. A

  18. Kinematics of ram filter feeding and beat-glide swimming in the northern anchovy Engraulis mordax.

    Science.gov (United States)

    Carey, Nicholas; Goldbogen, Jeremy A

    2017-08-01

    In the dense aquatic environment, the most adept swimmers are streamlined to reduce drag and increase the efficiency of locomotion. However, because they open their mouth to wide gape angles to deploy their filtering apparatus, ram filter feeders apparently switch between diametrically opposite swimming modes: highly efficient, streamlined 'beat-glide' swimming, and ram filter feeding, which has been hypothesized to be a high-cost feeding mode because of presumed increased drag. Ram filter-feeding forage fish are thought to play an important role in the flux of nutrients and energy in upwelling ecosystems; however, the biomechanics and energetics of this feeding mechanism remain poorly understood. We quantified the kinematics of an iconic forage fish, the northern anchovy, Engraulis mordax , during ram filter feeding and non-feeding, mouth-closed beat-glide swimming. Although many kinematic parameters between the two swimming modes were similar, we found that swimming speeds and tailbeat frequencies were significantly lower during ram feeding. Rather than maintain speed with the school, a speed which closely matches theoretical optimum filter-feeding speeds was consistently observed. Beat-glide swimming was characterized by high variability in all kinematic parameters, but variance in kinematic parameters was much lower during ram filter feeding. Under this mode, body kinematics are substantially modified, and E. mordax swims more slowly and with decreased lateral movement along the entire body, but most noticeably in the anterior. Our results suggest that hydrodynamic effects that come with deployment of the filtering anatomy may limit behavioral options during foraging and result in slower swimming speeds during ram filtration. © 2017. Published by The Company of Biologists Ltd.

  19. Tuning the conductivity and inner structure of electrospun fibers to promote cardiomyocyte elongation and synchronous beating.

    Science.gov (United States)

    Liu, Yaowen; Lu, Jinfu; Xu, Guisen; Wei, Jiaojun; Zhang, Zhibin; Li, Xiaohong

    2016-12-01

    The key to addressing the challenges facing cardiac tissue engineering is the integration of physical, chemical, and electrical cues into scaffolds. Aligned and conductive scaffolds have been fabricated as synthetic microenvironments to improve the function of cardiomyocytes. However, up to now, the influence of conductive capability and inner structure of fibrous scaffolds have not been determined on the cardiomyocyte morphologies and beating patterns. In the current study, highly aligned fibers were fabricated with loaded up to 6% of carbon nanotubes (CNTs) to modulate the electrical conductivity, while blend and coaxial electrospinning were utilized to create a bulk distribution of CNTs in fiber matrices and a spatial embedment in fiber cores, respectively. Conductive networks were formed in the fibrous scaffolds after the inoculation of over 3% CNTs, and the increase in the conductivity could maintain the cell viabilities, induce the cell elongation, enhance the production of sarcomeric α-actinin and troponin I, and promote the synchronous beating of cardiomyocytes. Although the conductivity of blend fibers is slightly higher than that of coaxial fibers with the same CNT loadings, the lower exposures to CNTs resulted in higher cell viability, elongation, extracellular matrix secretion and beating rates for cardiomyocytes on coaxial fibers. Taken altogether, core-sheath fibers with loaded 5% of CNTs in the fiber cores facilitated the cardiomyocyte growth with a production of organized contractile proteins and a pulsation frequency close to that of the atrium. It is suggested that electrospun scaffolds that couple conductivity and fibrous structure considerations may provide optimal stimuli to foster cell morphology and functions for myocardial regeneration or establishment of in vitro cardiomyocyte culture platform for drug screening. Copyright © 2016. Published by Elsevier B.V.

  20. Energy cascading in the beat-wave accelerator

    International Nuclear Information System (INIS)

    McKinstrie, C.J.; Batha, S.H.

    1987-01-01

    A review is given of energy cascading in the beat-wave accelerator. The properties of the electromagnetic cascade and the corresponding plasma-wave evolution are well understood within the framework of an approximate analytic model. Based on this model, idealized laser-plasma coupling efficiencies of the order of 10% do not seem unreasonable. 28 refs

  1. Popular Music in Southeast Asia : Banal Beats, Muted Histories

    NARCIS (Netherlands)

    Barendregt, Bart; Keppy, Peter; Schulte Nordholt, Henk

    2017-01-01

    'Popular Music in Southeast Asia: Banal Beats, Muted Histories' offers a cultural history of modern Southeast Asia from the original vantage point of popular music since the 1920s up to the present. By creatively connecting indigenous musical styles with foreign musical genres, Southeast Asians

  2. Wife beating amongst Africans as a challenge to pastoral care

    Directory of Open Access Journals (Sweden)

    Magezi E. Baloyi

    2013-11-01

    Full Text Available Traditional African people are known for respecting their marriage. Even though marriage is so highly regarded, it is astonishing to realise that wife beating has become an extremely common practice amongst them. It therefore becomes an important research question to ask about the extent to which deeply-seated traditional customs regarding wife beating as a form of stamping down authority and of trying to keep the household in order, will have to be confronted with what is deemed to be good practice from the perspective of the law, community and pastoral caregivers. There are women who live with scars on their faces and bodies, having been beaten by their husbands. Although there are many forms of abuse towards women in family situations, this article aims particularly to focus on wife beating that is practiced for traditional as well as other related reasons. This research will involve itself with establishing whether the reasons for wife beating are part of the traditional system for keeping the household in order and interrogate both legal and pastoral interventions that attempt to eliminate or avoid such behaviour.

  3. Subdividing the beat: auditory and motor contributions to synchronization

    NARCIS (Netherlands)

    Loehr, J.D.; Palmer, C.

    2009-01-01

    THE CURRENT STUDY EXAMINED HOW AUDITORY AND kinematic information influenced pianists' ability to synchronize musical sequences with a metronome. Pianists performed melodies in which quarter-note beats were subdivided by intervening eighth notes that resulted from auditory information (heard tones),

  4. Beat-wave accelerator studies at the Rutherford Appleton Laboratory

    International Nuclear Information System (INIS)

    Lawson, J.D.

    1985-01-01

    The study carried out in 1982-83 at the Rutherford Appleton Laboratory to examine how one might use the beat-wave principle to construct a useful high energy accelerator is reviewed, and comments are made on later developments. A number of problems are evident to which solutions cannot at present be foreseen. (author)

  5. Intimate partner abuse: wife beating among civil servants in Ibadan ...

    African Journals Online (AJOL)

    Wife beating is one of the most common forms of violence against women by husbands ... Consuming alcohol and growing up in an environment where parents fight publicly ... There is an urgent need for education of the women on their rights, ...

  6. Robust electrocardiogram (ECG) beat classification using discrete wavelet transform

    International Nuclear Information System (INIS)

    Minhas, Fayyaz-ul-Amir Afsar; Arif, Muhammad

    2008-01-01

    This paper presents a robust technique for the classification of six types of heartbeats through an electrocardiogram (ECG). Features extracted from the QRS complex of the ECG using a wavelet transform along with the instantaneous RR-interval are used for beat classification. The wavelet transform utilized for feature extraction in this paper can also be employed for QRS delineation, leading to reduction in overall system complexity as no separate feature extraction stage would be required in the practical implementation of the system. Only 11 features are used for beat classification with the classification accuracy of ∼99.5% through a KNN classifier. Another main advantage of this method is its robustness to noise, which is illustrated in this paper through experimental results. Furthermore, principal component analysis (PCA) has been used for feature reduction, which reduces the number of features from 11 to 6 while retaining the high beat classification accuracy. Due to reduction in computational complexity (using six features, the time required is ∼4 ms per beat), a simple classifier and noise robustness (at 10 dB signal-to-noise ratio, accuracy is 95%), this method offers substantial advantages over previous techniques for implementation in a practical ECG analyzer

  7. Using Science and Much More to Beat the Flood

    Science.gov (United States)

    Seeley, Claire

    2014-01-01

    The Beat the Flood challenge involves designing and building a model flood-proof home, which is then tested in "flood" conditions. It is set on the fictitious Watu Island. The children form teams, with each team member being assigned a responsibility for the duration of the task--team leader, chief recorder, and resource manager. This…

  8. Asynchronous beating of cilia enhances particle capture rate

    Science.gov (United States)

    Ding, Yang; Kanso, Eva

    2014-11-01

    Many aquatic micro-organisms use beating cilia to generate feeding currents and capture particles in surrounding fluids. One of the capture strategies is to ``catch up'' with particles when a cilium is beating towards the overall flow direction (effective stroke) and intercept particles on the downstream side of the cilium. Here, we developed a 3D computational model of a cilia band with prescribed motion in a viscous fluid and calculated the trajectories of the particles with different sizes in the fluid. We found an optimal particle diameter that maximizes the capture rate. The flow field and particle motion indicate that the low capture rate of smaller particles is due to the laminar flow in the neighbor of the cilia, whereas larger particles have to move above the cilia tips to get advected downstream which decreases their capture rate. We then analyzed the effect of beating coordination between neighboring cilia on the capture rate. Interestingly, we found that asynchrony of the beating of the cilia can enhance the relative motion between a cilium and the particles near it and hence increase the capture rate.

  9. An empirical investigation of attitudes towards wife-beating among ...

    African Journals Online (AJOL)

    With the exception of Uganda, women working for pay were more likely to justify wife-beating than non-working women were. The results indicate that dominant social and cultural norms create images of \\"ideal\\" women among both men and women that include definition and widespread acceptance of gender roles as well ...

  10. Efficiency of brainwave entrainment by binaural beats in reducing anxiety

    Directory of Open Access Journals (Sweden)

    Ahmad Alipoor

    2014-04-01

    Full Text Available Background: Anxiety is a fundamental phenomenon that is a common symptom in all mental disorders. The aim of the present study was to assess the effect of brainwave entrainment on anxiety reduction using binaural beats. Methods: In this experimental double-blind study, 30 employees were selected from an engineering research firm through random sampling and replacement and divided into two groups: control group and experimental group. All participants completed the Spielberger’s State-Trait Anxiety Inventory (STAI. Then, the experimental group listened to binaural beats which was recorded on a non-vocal piece of music for 4 weeks, 3 sessions each week. Each session lasted about 20 minutes. At the same time, the control group listened to the background music without any entrainment sound. At the end, both groups completed the anxiety questionnaire and the anxiety scores of both groups obtained before and after intervention were analyzed by ANCOVA. Results: The findings showed that the brainwave entrainment using binaural beats led to the significant reduction of state anxiety (P<0.001 and trait anxiety (P<0.018. Conclusion: Brainwave entrainment using binaural beats is an effective factor in decreasing state and trait anxiety; so, it can be used to reduce anxiety in mental health centers.

  11. VAMP7 modulates ciliary biogenesis in kidney cells.

    Directory of Open Access Journals (Sweden)

    Christina M Szalinski

    Full Text Available Epithelial cells elaborate specialized domains that have distinct protein and lipid compositions, including the apical and basolateral surfaces and primary cilia. Maintaining the identity of these domains is required for proper cell function, and requires the efficient and selective SNARE-mediated fusion of vesicles containing newly synthesized and recycling proteins with the proper target membrane. Multiple pathways exist to deliver newly synthesized proteins to the apical surface of kidney cells, and the post-Golgi SNAREs, or VAMPs, involved in these distinct pathways have not been identified. VAMP7 has been implicated in apical protein delivery in other cell types, and we hypothesized that this SNARE would have differential effects on the trafficking of apical proteins known to take distinct routes to the apical surface in kidney cells. VAMP7 expressed in polarized Madin Darby canine kidney cells colocalized primarily with LAMP2-positive compartments, and siRNA-mediated knockdown modulated lysosome size, consistent with the known function of VAMP7 in lysosomal delivery. Surprisingly, VAMP7 knockdown had no effect on apical delivery of numerous cargoes tested, but did decrease the length and frequency of primary cilia. Additionally, VAMP7 knockdown disrupted cystogenesis in cells grown in a three-dimensional basement membrane matrix. The effects of VAMP7 depletion on ciliogenesis and cystogenesis are not directly linked to the disruption of lysosomal function, as cilia lengths and cyst morphology were unaffected in an MDCK lysosomal storage disorder model. Together, our data suggest that VAMP7 plays an essential role in ciliogenesis and lumen formation. To our knowledge, this is the first study implicating an R-SNARE in ciliogenesis and cystogenesis.

  12. Midbrain adaptation may set the stage for the perception of musical beat

    Science.gov (United States)

    2017-01-01

    The ability to spontaneously feel a beat in music is a phenomenon widely believed to be unique to humans. Though beat perception involves the coordinated engagement of sensory, motor and cognitive processes in humans, the contribution of low-level auditory processing to the activation of these networks in a beat-specific manner is poorly understood. Here, we present evidence from a rodent model that midbrain preprocessing of sounds may already be shaping where the beat is ultimately felt. For the tested set of musical rhythms, on-beat sounds on average evoked higher firing rates than off-beat sounds, and this difference was a defining feature of the set of beat interpretations most commonly perceived by human listeners over others. Basic firing rate adaptation provided a sufficient explanation for these results. Our findings suggest that midbrain adaptation, by encoding the temporal context of sounds, creates points of neural emphasis that may influence the perceptual emergence of a beat. PMID:29118141

  13. Ahmed glaucoma valve implantation with tube insertion through the ciliary sulcus in pseudophakic/aphakic eyes.

    Science.gov (United States)

    Eslami, Yadolla; Mohammadi, Massood; Fakhraie, Ghasem; Zarei, Reza; Moghimi, Sasan

    2014-02-01

    To report the efficacy and safety of Ahmed glaucoma valve (AGV) insertion into the ciliary sulcus in pseudophakic/aphakic patients. A chart review was done on patients with uncontrolled glaucoma, who underwent AGV implantation with tube inserted into the ciliary sulcus. Baseline intraocular pressure (IOP) and number of medications were compared with that of postoperative follow-up visits. Surgical success was defined as last IOP glaucoma control, and without loss of light perception. Postoperative complications were recorded. Twenty-three eyes of 23 patients were recruited with the mean follow-up of 9 months (range, 3 to 24 mo). The mean (SD) age of patients was 49.9 (16.9) years (range, 22 to 80 years). The mean (SD) IOP (mm Hg) was reduced from 37.9 (12.4) before surgery to 16.2 (3.6) at the last follow-up visit (P<0.001). The mean (SD) number of medications was reduced from 3.3 (0.9) preoperatively to 1 (1.1) at the last follow-up (P<0.001). Success rate was 18/23 (78.6%). Complications included endophthalmitis in 1 eye, tube exposure in 1 diabetic patient, and vitreous tube occlusion in 1 eye. No case of corneal decompensation or graft failure was seen during follow-up. Ciliary sulcus placement of the tube of AGV effectively reduces IOP and medication use in short term. It has the potential to lower corneal complications of anterior chamber tube insertion and avoids the need for pars plana vitrectomy and tube insertion in patients at higher risk of corneal decompensation.

  14. Flagellar Synchronization Is a Simple Alternative to Cell Cycle Synchronization for Ciliary and Flagellar Studies.

    Science.gov (United States)

    Dutta, Soumita; Avasthi, Prachee

    2017-01-01

    The unicellular green alga Chlamydomonas reinhardtii is an ideal model organism for studies of ciliary function and assembly. In assays for biological and biochemical effects of various factors on flagellar structure and function, synchronous culture is advantageous for minimizing variability. Here, we have characterized a method in which 100% synchronization is achieved with respect to flagellar length but not with respect to the cell cycle. The method requires inducing flagellar regeneration by amputation of the entire cell population and limiting regeneration time. This results in a maximally homogeneous distribution of flagellar lengths at 3 h postamputation. We found that time-limiting new protein synthesis during flagellar synchronization limits variability in the unassembled pool of limiting flagellar protein and variability in flagellar length without affecting the range of cell volumes. We also found that long- and short-flagella mutants that regenerate normally require longer and shorter synchronization times, respectively. By minimizing flagellar length variability using a simple method requiring only hours and no changes in media, flagellar synchronization facilitates the detection of small changes in flagellar length resulting from both chemical and genetic perturbations in Chlamydomonas . This method increases our ability to probe the basic biology of ciliary size regulation and related disease etiologies. IMPORTANCE Cilia and flagella are highly conserved antenna-like organelles that found in nearly all mammalian cell types. They perform sensory and motile functions contributing to numerous physiological and developmental processes. Defects in their assembly and function are implicated in a wide range of human diseases ranging from retinal degeneration to cancer. Chlamydomonas reinhardtii is an algal model system for studying mammalian cilium formation and function. Here, we report a simple synchronization method that allows detection of small

  15. Cardiac arrhythmia beat classification using DOST and PSO tuned SVM.

    Science.gov (United States)

    Raj, Sandeep; Ray, Kailash Chandra; Shankar, Om

    2016-11-01

    The increase in the number of deaths due to cardiovascular diseases (CVDs) has gained significant attention from the study of electrocardiogram (ECG) signals. These ECG signals are studied by the experienced cardiologist for accurate and proper diagnosis, but it becomes difficult and time-consuming for long-term recordings. Various signal processing techniques are studied to analyze the ECG signal, but they bear limitations due to the non-stationary behavior of ECG signals. Hence, this study aims to improve the classification accuracy rate and provide an automated diagnostic solution for the detection of cardiac arrhythmias. The proposed methodology consists of four stages, i.e. filtering, R-peak detection, feature extraction and classification stages. In this study, Wavelet based approach is used to filter the raw ECG signal, whereas Pan-Tompkins algorithm is used for detecting the R-peak inside the ECG signal. In the feature extraction stage, discrete orthogonal Stockwell transform (DOST) approach is presented for an efficient time-frequency representation (i.e. morphological descriptors) of a time domain signal and retains the absolute phase information to distinguish the various non-stationary behavior ECG signals. Moreover, these morphological descriptors are further reduced in lower dimensional space by using principal component analysis and combined with the dynamic features (i.e based on RR-interval of the ECG signals) of the input signal. This combination of two different kinds of descriptors represents each feature set of an input signal that is utilized for classification into subsequent categories by employing PSO tuned support vector machines (SVM). The proposed methodology is validated on the baseline MIT-BIH arrhythmia database and evaluated under two assessment schemes, yielding an improved overall accuracy of 99.18% for sixteen classes in the category-based and 89.10% for five classes (mapped according to AAMI standard) in the patient

  16. IFT20 modulates ciliary PDGFRα signaling by regulating the stability of Cbl E3 ubiquitin ligases

    DEFF Research Database (Denmark)

    Schmid, Fabian Marc; Schou, Kenneth Bødtker; Vilhelm, Martin Juel

    2018-01-01

    ciliogenesis, and ciliary localization of the receptor is required for its appropriate ligand-mediated activation by PDGF-AA. However, the mechanisms regulating sorting of PDGFRα and feedback inhibition of PDGFRα signaling at the cilium are unknown. Here, we provide evidence that intraflagellar transport...... protein 20 (IFT20) interacts with E3 ubiquitin ligases c-Cbl and Cbl-b and is required for Cbl-mediated ubiquitination and internalization of PDGFRα for feedback inhibition of receptor signaling. In wild-type cells treated with PDGF-AA, c-Cbl becomes enriched in the cilium, and the receptor...

  17. Mutations in DZIP1L, which encodes a ciliary transition zone protein, cause autosomal recessive polycystic kidney disease

    Science.gov (United States)

    Lu, Hao; Galeano, Maria C. Rondón; Ott, Elisabeth; Kaeslin, Geraldine; Kausalya, P. Jaya; Kramer, Carina; Ortiz-Brüchle, Nadina; Hilger, Nadescha; Metzis, Vicki; Hiersche, Milan; Tay, Shang Yew; Tunningley, Robert; Vij, Shubha; Courtney, Andrew D.; Whittle, Belinda; Wühl, Elke; Vester, Udo; Hartleben, Björn; Neuber, Steffen; Frank, Valeska; Little, Melissa H.; Epting, Daniel; Papathanasiou, Peter; Perkins, Andrew C.; Wright, Graham D.; Hunziker, Walter; Gee, Heon Yung; Otto, Edgar A.; Zerres, Klaus; Hildebrandt, Friedhelm; Roy, Sudipto; Wicking, Carol; Bergmann, Carsten

    2017-01-01

    Autosomal recessive polycystic kidney disease (ARPKD), usually considered to be a genetically homogeneous disease caused by mutations in PKHD1, has been associated with ciliary dysfunction. Here, we describe mutations in the DAZ interacting protein 1-like (DZIP1L) gene in patients with ARPKD, findings we have further validated by loss-of-function studies in mice and zebrafish. DZIP1L localizes to centrioles and at the distal end of basal bodies, and interacts with septin2, a protein implicated in maintenance of the periciliary diffusion barrier at the ciliary transition zone. Consistent with a defect in the diffusion barrier, we found that the ciliary membrane translocation of the PKD proteins, polycystin-1 and −2, is compromised in DZIP1L mutant cells. Together, these data provide the first conclusive evidence that ARPKD is not a homogeneous disorder, and establishes DZIP1L as a second gene involved in its pathogenesis. PMID:28530676

  18. Mutations in DZIP1L, which encodes a ciliary-transition-zone protein, cause autosomal recessive polycystic kidney disease.

    Science.gov (United States)

    Lu, Hao; Galeano, Maria C Rondón; Ott, Elisabeth; Kaeslin, Geraldine; Kausalya, P Jaya; Kramer, Carina; Ortiz-Brüchle, Nadina; Hilger, Nadescha; Metzis, Vicki; Hiersche, Milan; Tay, Shang Yew; Tunningley, Robert; Vij, Shubha; Courtney, Andrew D; Whittle, Belinda; Wühl, Elke; Vester, Udo; Hartleben, Björn; Neuber, Steffen; Frank, Valeska; Little, Melissa H; Epting, Daniel; Papathanasiou, Peter; Perkins, Andrew C; Wright, Graham D; Hunziker, Walter; Gee, Heon Yung; Otto, Edgar A; Zerres, Klaus; Hildebrandt, Friedhelm; Roy, Sudipto; Wicking, Carol; Bergmann, Carsten

    2017-07-01

    Autosomal recessive polycystic kidney disease (ARPKD), usually considered to be a genetically homogeneous disease caused by mutations in PKHD1, has been associated with ciliary dysfunction. Here, we describe mutations in DZIP1L, which encodes DAZ interacting protein 1-like, in patients with ARPKD. We further validated these findings through loss-of-function studies in mice and zebrafish. DZIP1L localizes to centrioles and to the distal ends of basal bodies, and interacts with septin2, a protein implicated in maintenance of the periciliary diffusion barrier at the ciliary transition zone. In agreement with a defect in the diffusion barrier, we found that the ciliary-membrane translocation of the PKD proteins polycystin-1 and polycystin-2 is compromised in DZIP1L-mutant cells. Together, these data provide what is, to our knowledge, the first conclusive evidence that ARPKD is not a homogeneous disorder and further establish DZIP1L as a second gene involved in ARPKD pathogenesis.

  19. Surgical treatment of iris and ciliary body melanoma: follow-up of a 25-year series of patients

    DEFF Research Database (Denmark)

    Klauber, Stefan; Jensen, Peter K; Prause, Jan U

    2010-01-01

    Purpose: To evaluate outcome of surgical resection of iris and irido-ciliary melanomas. Method: Retrospective analysis of all cases treated in Denmark 1975-1999 with clinical follow-up in 2002 and death certificate analysis in 2008. A quality of life questionnaire was completed at follow-up. Resu......Purpose: To evaluate outcome of surgical resection of iris and irido-ciliary melanomas. Method: Retrospective analysis of all cases treated in Denmark 1975-1999 with clinical follow-up in 2002 and death certificate analysis in 2008. A quality of life questionnaire was completed at follow...... time. However, none had changed job as a consequence of the surgical treatment. Only two patients were emotionally affected by the diagnosis of iris melanoma. Conclusion: Resection of small iris and irido-ciliary melanomas is a safe and efficient procedure, provided that strict diagnostic and surgical...

  20. Non-model-based correction of respiratory motion using beat-to-beat 3D spiral fat-selective imaging.

    Science.gov (United States)

    Keegan, Jennifer; Gatehouse, Peter D; Yang, Guang-Zhong; Firmin, David N

    2007-09-01

    To demonstrate the feasibility of retrospective beat-to-beat correction of respiratory motion, without the need for a respiratory motion model. A high-resolution three-dimensional (3D) spiral black-blood scan of the right coronary artery (RCA) of six healthy volunteers was acquired over 160 cardiac cycles without respiratory gating. One spiral interleaf was acquired per cardiac cycle, prior to each of which a complete low-resolution fat-selective 3D spiral dataset was acquired. The respiratory motion (3D translation) on each cardiac cycle was determined by cross-correlating a region of interest (ROI) in the fat around the artery in the low-resolution datasets with that on a reference end-expiratory dataset. The measured translations were used to correct the raw data of the high-resolution spiral interleaves. Beat-to-beat correction provided consistently good results, with the image quality being better than that obtained with a fixed superior-inferior tracking factor of 0.6 and better than (N = 5) or equal to (N = 1) that achieved using a subject-specific retrospective 3D translation motion model. Non-model-based correction of respiratory motion using 3D spiral fat-selective imaging is feasible, and in this small group of volunteers produced better-quality images than a subject-specific retrospective 3D translation motion model. (c) 2007 Wiley-Liss, Inc.

  1. What makes a rhythm complex? The influence of musical training and accent type on beat perception

    NARCIS (Netherlands)

    Bouwer, F.L.; Burgoyne, J.A.; Odijk, D.; Honing, H.; Grahn, J.A.

    2018-01-01

    Perception of a regular beat in music is inferred from different types of accents. For example, increases in loudness cause intensity accents, and the grouping of time intervals in a rhythm creates temporal accents. Accents are expected to occur on the beat: when accents are “missing” on the beat,

  2. Alteration of sodium, potassium-adenosine triphosphatase activity in rabbit ciliary processes by cyclic adenosine monophosphate-dependent protein kinase

    International Nuclear Information System (INIS)

    Delamere, N.A.; Socci, R.R.; King, K.L.

    1990-01-01

    The response of sodium, potassium-adenosine triphosphatase (Na,K-ATPase) to cyclic adenosine monophosphate (cAMP)-dependent protein kinase was examined in membranes obtained from rabbit iris-ciliary body. In the presence of the protein kinase together with 10(-5) M cAMP, Na,K-ATPase activity was reduced. No change in Na,K-ATPase activity was detected in response to the protein kinase without added cAMP. Likewise cAMP alone did not alter Na,K-ATPase activity. Reduction of Na,K-ATPase activity was also observed in the presence of the cAMP-dependent protein kinase catalytic subunit. The response of the enzyme to the kinase catalytic subunit was also examined in membranes obtained from rabbit ciliary processes. In the presence of 8 micrograms/ml of the catalytic subunit, ciliary process Na,K-ATPase activity was reduced by more than 50%. To examine whether other ATPases were suppressed by the protein kinase, calcium-stimulated ATPase activity was examined; its activity was stimulated by the catalytic subunit. To test whether the response of the ciliary process Na,K-ATPase is unique, experiments were also performed using membrane preparations from rabbit lens epithelium or rabbit kidney; the catalytic subunit significantly reduced the activity of Na,K-ATPase from the kidney but not the lens. These Na,K-ATPase studies suggest that in the iris-ciliary body, cAMP may alter sodium pump activity. In parallel 86Rb uptake studies, we observed that ouabain-inhibitable potassium uptake by intact pieces of iris-ciliary body was reduced by exogenous dibutryl cAMP or by forskolin

  3. Influence of mode-beating pulse on laser-induced plasma

    Science.gov (United States)

    Nishihara, M.; Freund, J. B.; Glumac, N. G.; Elliott, G. S.

    2018-04-01

    This paper addresses the influence of mode-beating pulse on laser-induced plasma. The second harmonic of a Nd:YAG laser, operated either with the single mode or multimode, was used for non-resonant optical breakdown, and subsequent plasma development was visualized using a streak imaging system. The single mode lasing leads to a stable breakdown location and smooth envelopment of the plasma boundary, while the multimode lasing, with the dominant mode-beating frequency of 500-800 MHz, leads to fluctuations in the breakdown location, a globally modulated plasma surface, and growth of local microstructures at the plasma boundary. The distribution of the local inhomogeneity was measured from the elastic scattering signals on the streak image. The distance between the local structures agreed with the expected wavelength of hydrodynamic instability development due to the interference between the surface excited wave and transmitted wave. A numerical simulation, however, indicates that the local microstructure could also be directly generated at the peaks of the higher harmonic components if the multimode pulse contains up to the eighth harmonic of the fundamental cavity mode.

  4. Suitability of tunneling ionization produced plasmas for the plasma beat wave accelerator

    International Nuclear Information System (INIS)

    Leeman, W.P.; Clayton, C.E.; Marsh, K.A.; Dyson, A.; Joshi, C.

    1991-01-01

    Tunneling ionization can be thought of as the high intensity, low frequency limit of multi-photon ionization (MPI). Extremely uniform plasmas were produced by the latter process at Rutherford lab for beat wave excitation experiments using a 0.5 μm laser. Plasmas with 100% ionization were produced with densities exceeding 10 17 cm -3 . The experiment uses a CO 2 laser (I max ∼ 5 x 10 14 W/cm 2 ) which allows the formation of plasmas via the tunneling process. For the experiments the authors need plasmas with densities in the range of 5 to 10 x 10 16 cm -3 . Using Thomson scattering as a diagnostic they have explored the density and temperature regime of tunneling ionization produced plasmas. They find that plasmas with densities up to 10 16 cm -3 can indeed be produced and that these plasmas are hot. Beyond this density strong refraction of laser radiation occurs due to the radial profile of the plasma. Implications of this work to the Beat Wave Accelerator program will be discussed

  5. Nonstationary self-action of electromagnetic wave beams in the beat accelerator

    International Nuclear Information System (INIS)

    Abramyan, L.A.; Litvak, A.G.; Mironov, V.A.

    1990-01-01

    The resonance excitation of a plasma wave in a modified accelerator using the beats of two electromagnetic waves permits to increase considerably the intensity of the accelerating field and, consequently, the rate of the accumulation of the energy by charged particles. The efficiency of the electromagnetic radiation conversion to the longitudinal wave is defined by nonlinear processes. The saturation of the accelerating field is considered which is due to the appearance of multiflux motion of electrons oscillating in the wave field with overturn of waves, due to the development of parametric instabilities and due to the change of natural frequency of plasma oscillations caused by the relativistic increase of electron mass. The effects of self-action which change the form of the electromagnetic radiation pulse and the wave beam structure play a significant role in the most promising laser plasma beat accelerator. We consider dynamics of space distribution of the plasma wave in a self-consistent field of the wave beam. (author) 5 refs., 2 figs

  6. Fetal beat detection in abdominal ECG recordings: global and time adaptive approaches

    International Nuclear Information System (INIS)

    Rodrigues, Rui

    2014-01-01

    We present a method for location of fetal QRS in maternal abdominal ECG recordings. This method’s initial, global approach was proposed in the context of the 2013 PhysioNet/Computing in Cardiology Challenge where it was tested on the 447 four channel one-minute recordings. The first step is filtering to eliminate baseline wander and high frequency noise. Upon detection, maternal QRS is removed on each channel using a filter applied to the other three channels. Next we locate fetal QRS on each channel and select the channel with the best set of detections. The method was awarded the third-best score in the Challenge event 1 with 278.755 (beats/minute) and the fourth-best score on event 2 with 28.201 ms. The 5 min long recordings of the Abdominal and Direct Fetal ECG Database were used to further test the method. This database contains five recordings obtained from women in labor. Results in these longer recordings were not satisfactory. This appears to be particularly the case in recordings with a more clearly non-stationary nature. In a new approach to our method, some changes are introduced. Two features are updated over time: the filter used to eliminate maternal QRS and the channel used to detect fetal beats. These changes significantly improved the QRS detection performance on longer recordings, but the scores on the 1 minute Challenge recordings were degraded. (paper)

  7. Beat-to-beat systolic time-interval measurement from heart sounds and ECG

    International Nuclear Information System (INIS)

    Paiva, R P; Carvalho, P; Couceiro, R; Henriques, J; Antunes, M; Quintal, I; Muehlsteff, J

    2012-01-01

    Systolic time intervals are highly correlated to fundamental cardiac functions. Several studies have shown that these measurements have significant diagnostic and prognostic value in heart failure condition and are adequate for long-term patient follow-up and disease management. In this paper, we investigate the feasibility of using heart sound (HS) to accurately measure the opening and closing moments of the aortic heart valve. These moments are crucial to define the main systolic timings of the heart cycle, i.e. pre-ejection period (PEP) and left ventricular ejection time (LVET). We introduce an algorithm for automatic extraction of PEP and LVET using HS and electrocardiogram. PEP is estimated with a Bayesian approach using the signal's instantaneous amplitude and patient-specific time intervals between atrio-ventricular valve closure and aortic valve opening. As for LVET, since the aortic valve closure corresponds to the start of the S2 HS component, we base LVET estimation on the detection of the S2 onset. A comparative assessment of the main systolic time intervals is performed using synchronous signal acquisitions of the current gold standard in cardiac time-interval measurement, i.e. echocardiography, and HS. The algorithms were evaluated on a healthy population, as well as on a group of subjects with different cardiovascular diseases (CVD). In the healthy group, from a set of 942 heartbeats, the proposed algorithm achieved 7.66 ± 5.92 ms absolute PEP estimation error. For LVET, the absolute estimation error was 11.39 ± 8.98 ms. For the CVD population, 404 beats were used, leading to 11.86 ± 8.30 and 17.51 ± 17.21 ms absolute PEP and LVET errors, respectively. The results achieved in this study suggest that HS can be used to accurately estimate LVET and PEP. (paper)

  8. Viscosity and not biological mechanisms often controls the effects of temperature on ciliary activity and swimming velocity of small aquatic organisms

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Riisgård, H. U.

    2009-01-01

    organisms using cilia or small appendages for propulsion. Here we summarize results from the literature and from own studies on bio-mechanical activities in response to changing temperature or manipulated viscosity at constant temperature, both having the same change in kinematic viscosity. The survey......A number of studies have shown that temperature-dependent viscosity of the ambient water controls or strongly affects bio-mechanical activity such as beat frequency of water-pumping cilia in mussels and ascidians, swimming velocity of sperm cells, ciliates and small (micro- and meso-scale) aquatic...

  9. Diagnosis of primary ciliary dyskinesia: potential options for resource-limited countries

    Directory of Open Access Journals (Sweden)

    Nisreen Rumman

    2017-01-01

    Full Text Available Primary ciliary dyskinesia is a genetic disease of ciliary function leading to chronic upper and lower respiratory tract symptoms. The diagnosis is frequently overlooked because the symptoms are nonspecific and the knowledge about the disease in the primary care setting is poor. Additionally, none of the available tests is accurate enough to be used in isolation. These tests are expensive, and need sophisticated equipment and expertise to analyse and interpret results; diagnosis is therefore only available at highly specialised centres. The diagnosis is particularly challenging in countries with limited resources due to the lack of such costly equipment and expertise. In this review, we discuss the importance of early and accurate diagnosis especially for countries where the disease is clinically prevalent but diagnostic tests are lacking. We review the diagnostic tests available in specialised centres (nasal nitric oxide, high-speed video microscopy, transmission electron microscopy, immunofluorescence and genetics. We then consider modifications that might be considered in less well-resourced countries whilst maintaining acceptable accuracy.

  10. C2 Domains as Protein-Protein Interaction Modules in the Ciliary Transition Zone

    Directory of Open Access Journals (Sweden)

    Kim Remans

    2014-07-01

    Full Text Available RPGR-interacting protein 1 (RPGRIP1 is mutated in the eye disease Leber congenital amaurosis (LCA and its structural homolog, RPGRIP1-like (RPGRIP1L, is mutated in many different ciliopathies. Both are multidomain proteins that are predicted to interact with retinitis pigmentosa G-protein regulator (RPGR. RPGR is mutated in X-linked retinitis pigmentosa and is located in photoreceptors and primary cilia. We solved the crystal structure of the complex between the RPGR-interacting domain (RID of RPGRIP1 and RPGR and demonstrate that RPGRIP1L binds to RPGR similarly. RPGRIP1 binding to RPGR affects the interaction with PDEδ, the cargo shuttling factor for prenylated ciliary proteins. RPGRIP1-RID is a C2 domain with a canonical β sandwich structure that does not bind Ca2+ and/or phospholipids and thus constitutes a unique type of protein-protein interaction module. Judging from the large number of C2 domains in most of the ciliary transition zone proteins identified thus far, the structure presented here seems to constitute a cilia-specific module that is present in multiprotein transition zone complexes.

  11. Genotypic variation in response to salinity in a new sexual germplasm of Cenchrus ciliaris L.

    Science.gov (United States)

    Quiroga, Mariana; Tommasino, Exequiel; Griffa, Sabrina; Ribotta, Andrea; Colomba, Eliana López; Carloni, Edgardo; Grunberg, Karina

    2016-05-01

    As part of a breeding program for new salt-tolerant sexual genotypes of Cenchrus ciliaris L., here we evaluated the salt-stress response of two new sexual hybrids, obtained by controlled crosses, at seedling and germination stages. A seedling hydroponic experiment with 300 mM NaCl was performed and physiological variables and growth components were evaluated. While salt-treated sexual material did not show a decrease in productivity with respect to control plants, a differential response in some physiological characteristics was observed. Sexual hybrid 1-9-1 did not suffer oxidative damage and its proline content did not differ from that of control treatment. By contrast, sexual hybrid 1-7-11 suffered oxidative damage and accumulated proline, maintaining its growth under saline stress. At the germination stage, sexual hybrid 1-9-1 presented the highest Germination Rate Index at the maximum NaCl concentration assayed, suggesting an ecological advantage in this genotype. These new sexual resources are promising maternal parental with differential response to salt and could be incorporated in a breeding program of C. ciliaris in the search of new genotypes tolerant to salinity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  12. Posterior Ciliary Artery Occlusion Caused by Hyaluronic Acid Injections Into the Forehead: A Case Report.

    Science.gov (United States)

    Hu, Xiu Zhuo; Hu, Jun Yan; Wu, Peng Sen; Yu, Sheng Bo; Kikkawa, Don O; Lu, Wei

    2016-03-01

    Although cosmetic facial soft tissue fillers are generally safe and effective, improper injections can lead to devastating and irreversible consequences. We represent the first known case of posterior ciliary artery occlusion caused by hyaluronic acid. A 41-year-old female presented with right visual loss 7 hours after receiving cosmetic hyaluronic acid injections into her forehead. Examination revealed no light perception in the right eye and multiple dark ischemic area of injection over the forehead and nose. The right fundus revealed a pink retina with optic nerve edema. Fluorescein angiogram showed several filling defects in the choroidal circulation and late hyperfluorescence in the choroid. A right posterior ciliary artery occlusion and embolic occlusion of facial artery braches was diagnosed. With hyaluronidase injection, hyperbaric oxygen therapy, oral aspirin, oral acetazolamide and dexamethasone venotransfuse treatment, the patient's forehead and nasal skin improved and vision recovered to hand movements. With proper technique, vascular occlusion is rare following facial filler injection. Vision consequences can be severe if filler emboli enter the ocular circulation. Physicians should be aware of this potential side effect, recognize its presentation, and be knowledgeable of effective management.

  13. Convergent evolution of RFX transcription factors and ciliary genes predated the origin of metazoans

    Directory of Open Access Journals (Sweden)

    Chen Nansheng

    2010-05-01

    Full Text Available Abstract Background Intraflagellar transport (IFT genes, which are critical for the development and function of cilia and flagella in metazoans, are tightly regulated by the Regulatory Factor X (RFX transcription factors (TFs. However, how and when their evolutionary relationship was established remains unknown. Results We have identified evidence suggesting that RFX TFs and IFT genes evolved independently and their evolution converged before the first appearance of metazoans. Both ciliary genes and RFX TFs exist in all metazoans as well as some unicellular eukaryotes. However, while RFX TFs and IFT genes are found simultaneously in all sequenced metazoan genomes, RFX TFs do not co-exist with IFT genes in most pre-metazoans and thus do not regulate them in these organisms. For example, neither the budding yeast nor the fission yeast possesses cilia although both have well-defined RFX TFs. Conversely, most unicellular eukaryotes, including the green alga Chlamydomonas reinhardtii, have typical cilia and well conserved IFT genes but lack RFX TFs. Outside of metazoans, RFX TFs and IFT genes co-exist only in choanoflagellates including M. brevicollis, and only one fungus Allomyces macrogynus of the 51 sequenced fungus genomes. M. brevicollis has two putative RFX genes and a full complement of ciliary genes. Conclusions The evolution of RFX TFs and IFT genes were independent in pre-metazoans. We propose that their convergence in evolution, or the acquired transcriptional regulation of IFT genes by RFX TFs, played a pivotal role in the establishment of metazoan.

  14. Primary ciliary dyskinesia-causing mutations in Amish and Mennonite communities.

    Science.gov (United States)

    Ferkol, Thomas W; Puffenberger, Erik G; Lie, Hauw; Helms, Cynthia; Strauss, Kevin A; Bowcock, Anne; Carson, John L; Hazucha, Milan; Morton, D Holmes; Patel, Anand C; Leigh, Margaret W; Knowles, Michael R; Zariwala, Maimoona A

    2013-08-01

    To determine whether individuals with primary ciliary dyskinesia (PCD) from unrelated Amish and Mennonite families harbor a single and unique founder mutation. Subjects from Amish and Mennonite communities in several states were enrolled in the study. All subjects were clinically characterized, and nasal nitric oxide levels were measured. Nasal epithelial scrapings were collected from several subjects for ciliary ultrastructural analyses. DNA was isolated from patients with PCD and their unaffected first- and second-degree relatives. Genome-wide homozygosity mapping, linkage analyses, targeted mutation analyses, and exome sequencing were performed. All subjects from Old-Order Amish communities from Pennsylvania were homozygous for a nonsense mutant DNAH5 allele, c.4348C>T (p.Q1450X). Two affected siblings from an unrelated Mennonite family in Arkansas were homozygous for the same nonsense DNAH5 mutation. Children with PCD from an Amish family from Wisconsin had biallelic DNAH5 mutations, c.4348C>T (p.Q1450X) and c.10815delT (p.P3606HfsX23), and mutations in other genes associated with PCD were also identified in this community. The Amish and Mennonite subjects from geographically dispersed and socially isolated communities had the same founder DNAH5 mutation, owing to the common heritage of these populations. However, disease-causing mutations in other PCD-associated genes were also found in affected individuals in these communities, illustrating the genetic heterogeneity in this consanguineous population. Copyright © 2013 Mosby, Inc. All rights reserved.

  15. Melatonin synthesis in the human ciliary body triggered by TRPV4 activation: Involvement of AANAT phosphorylation.

    Science.gov (United States)

    Alkozi, Hanan Awad; Perez de Lara, María J; Pintor, Jesús

    2017-09-01

    Melatonin is a substance synthesized in the pineal gland as well as in other organs. This substance is involved in many ocular functions, giving its synthesis in numerous eye structures. Melatonin is synthesized from serotonin through two enzymes, the first limiting step into the synthesis of melatonin being aralkylamine N-acetyltransferase (AANAT). In this current study, AANAT phosphorylation after the activation of TRPV4 was studied using human non-pigmented epithelial ciliary body cells. Firstly, it was necessary to determine the adequate time and dose of the TRPV4 agonist GSK1016790A to reach the maximal phosphorylation of AANAT. An increase of 72% was observed after 5 min incubation with 10 nM GSK (**p melatonin synthesis. The involvement of a TRPV4 channel in melatonin synthesis was verified by antagonist and siRNA studies as a previous step to studying intracellular signalling. Studies performed on the second messengers involved in GSK induced AANAT phosphorylation were carried out by inhibiting several pathways. In conclusion, the activation of calmodulin and calmodulin-dependent protein kinase II was confirmed, as shown by the cascade seen in AANAT phosphorylation (***p melatonin levels. In conclusion, the activation of a TRPV4 present in human ciliary body epithelial cells produced an increase in AANAT phosphorylation and a further melatonin increase by a mechanism in which Ca-calmodulin and the calmodulin-dependent protein kinase II are involved. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. hemingway is required for sperm flagella assembly and ciliary motility in Drosophila.

    Science.gov (United States)

    Soulavie, Fabien; Piepenbrock, David; Thomas, Joëlle; Vieillard, Jennifer; Duteyrat, Jean-Luc; Cortier, Elisabeth; Laurençon, Anne; Göpfert, Martin C; Durand, Bénédicte

    2014-04-01

    Cilia play major functions in physiology and development, and ciliary dysfunctions are responsible for several diseases in humans called ciliopathies. Cilia motility is required for cell and fluid propulsion in organisms. In humans, cilia motility deficiencies lead to primary ciliary dyskinesia, with upper-airways recurrent infections, left-right asymmetry perturbations, and fertility defects. In Drosophila, we identified hemingway (hmw) as a novel component required for motile cilia function. hmw encodes a 604-amino acid protein characterized by a highly conserved coiled-coil domain also found in the human orthologue, KIAA1430. We show that HMW is conserved in species with motile cilia and that, in Drosophila, hmw is expressed in ciliated sensory neurons and spermatozoa. We created hmw-knockout flies and found that they are hearing impaired and male sterile. hmw is implicated in the motility of ciliated auditory sensory neurons and, in the testis, is required for elongation and maintenance of sperm flagella. Because HMW is absent from mature flagella, we propose that HMW is not a structural component of the motile axoneme but is required for proper acquisition of motile properties. This identifies HMW as a novel, evolutionarily conserved component necessary for motile cilium function and flagella assembly.

  17. Central Retinal and Posterior Ciliary Artery Occlusion After Intralesional Injection of Sclerosant to Glabellar Subcutaneous Hemangioma

    International Nuclear Information System (INIS)

    Matsuo, Toshihiko; Fujiwara, Hiroyasu; Gobara, Hideo; Mimura, Hidefumi; Kanazawa, Susumu

    2009-01-01

    The aim of this study is to describe vision loss caused by central retinal artery and posterior ciliary artery occlusion as a consequence of sclerotherapy with a polidocanol injection to a glabellar hemangioma. An 18-year-old man underwent direct injection with a 23-gauge needle of 1 mL of a polidocanol-carbon dioxide emulsion into the glabellar subcutaneous hemangioma under ultrasound visualization of the needle tip by radiologists. He developed lid swelling the next day, and 3 days later at referral, the visual acuity in the left eye was no light perception. Funduscopy revealed central retinal artery occlusion and fluorescein angiography disclosed no perfusion at all in the left fundus, indicating concurrent posterior ciliary artery occlusion. The patient also showed mydriasis, blepharoptosis, and total external ophthalmoplegia on the left side. Magnetic resonance imaging demonstrated the swollen medial rectus muscle. In a month, blepharoptosis and ophthalmoplegia resolved but the visual acuity remained no light perception. Sclerosing therapy for facial hemangioma may develop a severe complication such as permanent visual loss.

  18. [3H]acetylcholine synthesis in cultured ciliary ganglion neurons: effects of myotube membranes

    International Nuclear Information System (INIS)

    Gray, D.B.; Tuttle, J.B.

    1987-01-01

    Avian ciliary ganglion neurons in cell culture were examined for the capacity to synthesize acetylcholine (ACh) from the exogenously supplied precursor, choline. Relevant kinetic parameters of the ACh synthetic system in cultured neurons were found to be virtually the same as those of the ganglionic terminals in the intact iris. Neurons were cultured in the presence of and allowed to innervate pectoral muscle; this results in an capacity for ACh synthesis. In particular, the ability to increase ACh synthesis upon demand after stimulation is affected by interaction with the target. This effect is shown to be an acceleration of the maturation of the cultured neurons. Lysed and washed membrane remnants of the muscle target were able to duplicate, in part, this effect of live target tissue on neuronal transmitter metabolism. Culture medium conditioned by muscle, and by the membrane remnants of muscle, was without significant effect. Thus, substances secreted into the medium do not play a major role in this interaction. Neurons cultured with either muscle or muscle membrane remnants formed large, elongate structures on the target membrane surface. These were not seen in the absence of the target at the times examined. This morphological difference in terminal-like structures may parallel the developmental increases in size and vesicular content of ciliary ganglion nerve terminals in the chick iris, and may relate to the increased ACh synthetic activity. The results suggest that direct contact with an appropriate target membrane has a profound, retrograde influence upon neuronal metabolic and morphological maturation

  19. First Beta-Beating Measurement in the LHC

    CERN Document Server

    Aiba, M; Franchi, A; Giovannozzi, M; Kain, V; Morita, A; Tomás, R; Vanbavinckhove, G; Wenninger, J

    2009-01-01

    This note reports on the first LHC beta-beating and coupling measurements. Thanks to an excellent functioning of the BPM system and the related software, injection oscillations were recorded for the first 90 turns at all BPMs of Beam 2. Three different algorithms are used to measure the optics parameters from the BPM data. All algorithms show consistent measurements but feature different accuracy. The Singular Value Decomposition (SVD) approach shows a high resolution despite the limited number of turns. The vertical beta-beating is observed to be about a factor of two larger than in the horizontal plane. This asymetry is partly due to sextupoles misalignments but also suggests the possible existance of focusing errors at defocussing locations. Rather large coupling is observed since no skew quadrupole was excited at the time of the data acquisition. We also report a list of suspected malfunctioning BPMs identified through various analyses.

  20. Moving to the Beat and Singing are Linked in Humans

    Science.gov (United States)

    Dalla Bella, Simone; Berkowska, Magdalena; Sowiński, Jakub

    2015-01-01

    The abilities to sing and to move to the beat of a rhythmic auditory stimulus emerge early during development, and both engage perceptual, motor, and sensorimotor processes. These similarities between singing and synchronization to a beat may be rooted in biology. Patel (2008) has suggested that motor synchronization to auditory rhythms may have emerged during evolution as a byproduct of selection for vocal learning (“vocal learning and synchronization hypothesis”). This view predicts a strong link between vocal performance and synchronization skills in humans. Here, we tested this prediction by asking occasional singers to tap along with auditory pulse trains and to imitate familiar melodies. Both vocal imitation and synchronization skills were measured in terms of accuracy and precision or consistency. Accurate and precise singers tapped more in the vicinity of the pacing stimuli (i.e., they were more accurate) than less accurate and less precise singers. Moreover, accurate singers were more consistent when tapping to the beat. These differences cannot be ascribed to basic motor skills or to motivational factors. Individual differences in terms of singing proficiency and synchronization skills may reflect the variability of a shared sensorimotor translation mechanism. PMID:26733370

  1. Beliefs About Wife Beating Among Social Work Students in Taiwan.

    Science.gov (United States)

    Haj-Yahia, Muhammad M; Shen, April Chiung-Tao

    2017-07-01

    Based on an integrative framework, this study addresses the beliefs that a group of social work students from Taiwan had about wife beating. A self-administered questionnaire was filled out by 790 students (76.5% female, 23.5% male) spanning all 4 years of undergraduate studies. The results show that male students exhibited a greater tendency than their female counterparts to justify wife beating and to hold battered women responsible for violence against them. This tendency was also found among students who held traditional attitudes toward women, students who held patriarchal expectations of marriage, and students who had witnessed interparental violence in childhood. In addition, male students and students with traditional attitudes toward women exhibited the strongest tendency to believe that wives benefit from beating. Conversely, female students expressed more willingness than their male counterparts to help battered women, as did students who held liberal attitudes toward women and students who held egalitarian expectations of marriage. Furthermore, female students and those with liberal attitudes toward women tended to hold violent husbands responsible for their behavior, and to express support for punishing violent husbands. This article concludes with a discussion of the study's limitations and the results' implications for future research on the topic.

  2. Beating the Spin-Down Limit on Gravitational Wave Emission from the Crab Pulsar

    International Nuclear Information System (INIS)

    Abbott, B.; Babak, S.; Abbott, R.; Adhikari, R.; Anderson, S. B.; Araya, M.; Armandula, H.; Ballmer, S.; Ajith, P.; Allen, B.; Aulbert, C.; Allen, G.; Amin, R.; Anderson, W. G.; Armor, P.; Arain, M. A.; Aso, Y.; Aston, S.; Aufmuth, P.; Bantilan, H.

    2008-01-01

    We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first 9 months of the fifth science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). These limits are based on two searches. In the first we assume that the gravitational wave emission follows the observed radio timing, giving an upper limit on gravitational wave emission that beats indirect limits inferred from the spin-down and braking index of the pulsar and the energetics of the nebula. In the second we allow for a small mismatch between the gravitational and radio signal frequencies and interpret our results in the context of two possible gravitational wave emission mechanisms.

  3. CCDC151 mutations cause primary ciliary dyskinesia by disruption of the outer dynein arm docking complex formation

    DEFF Research Database (Denmark)

    Hjeij, Rim; Onoufriadis, Alexandros; Watson, Christopher M

    2014-01-01

    disorder of ciliary and flagellar dysmotility characterized by chronic upper and lower respiratory infections and defects in laterality. Here, by combined high-throughput mapping and sequencing, we identified CCDC151 loss-of-function mutations in five affected individuals from three independent families...

  4. X-linked primary ciliary dyskinesia due to mutations in the cytoplasmic axonemal dynein assembly factor PIH1D3.

    NARCIS (Netherlands)

    Olcese, C.; Patel, M.P.; Shoemark, A.; Kiviluoto, S.; Legendre, M.; Williams, H.J.; Vaughan, C.K.; Hayward, J.; Goldenberg, A.; Emes, R.D.; Munye, M.M.; Dyer, L.; Cahill, T.; Bevillard, J.; Gehrig, C.; Guipponi, M.; Chantot, S.; Duquesnoy, P.; Thomas, L.; Jeanson, L.; Copin, B.; Tamalet, A.; Thauvin-Robinet, C.; Papon, J.F.; Garin, A.; Pin, I.; Vera, G.; Aurora, P.; Fassad, M.R.; Jenkins, L.; Boustred, C.; Cullup, T.; Dixon, M.; Onoufriadis, A.; Bush, A.; Chung, E.M.; Antonarakis, S.E.; Loebinger, M.R.; Wilson, R.; Armengot, M.; Escudier, E.; Hogg, C.; Amselem, S.; Sun, Z.; Bartoloni, L.; Blouin, J.L.; Mitchison, H.M.; Schmidts, M.; et al.,

    2017-01-01

    By moving essential body fluids and molecules, motile cilia and flagella govern respiratory mucociliary clearance, laterality determination and the transport of gametes and cerebrospinal fluid. Primary ciliary dyskinesia (PCD) is an autosomal recessive disorder frequently caused by non-assembly of

  5. Recombination within the apospory specific genomic region leads to the uncoupling of apomixis components in Cenchrus ciliaris.

    Science.gov (United States)

    Conner, Joann A; Gunawan, Gunawati; Ozias-Akins, Peggy

    2013-07-01

    Apomixis enables the clonal propagation of maternal genotypes through seed. If apomixis could be harnessed via genetic engineering or introgression, it would have a major economic impact for agricultural crops. In the grass species Pennisetum squamulatum and Cenchrus ciliaris (syn. P. ciliare), apomixis is controlled by a single dominant "locus", the apospory-specific genomic region (ASGR). For P. squamulatum, 18 published sequenced characterized amplified region (SCAR) markers have been identified which always co-segregate with apospory. Six of these markers are conserved SCARs in the closely related species, C. ciliaris and co-segregate with the trait. A screen of progeny from a cross of sexual × apomictic C. ciliaris genotypes identified a plant, A8, retaining two of the six ASGR-linked SCAR markers. Additional and newly identified ASGR-linked markers were generated to help identify the extent of recombination within the ASGR. Based on analysis of missing markers, the A8 recombinant plant has lost a significant portion of the ASGR but continues to form aposporous embryo sacs. Seedlings produced from aposporous embryo sacs are 6× in ploidy level and hence the A8 recombinant does not express parthenogenesis. The recombinant A8 plant represents a step forward in reducing the complexity of the ASGR locus to determine the factor(s) required for aposporous embryo sac formation and documents the separation of expression of the two components of apomixis in C. ciliaris.

  6. Regulation of protein phosphorylation of the intermediate-sized filament vimentin in the ciliary epithelium of the mammalian eye

    International Nuclear Information System (INIS)

    Coca-Prados, M.

    1985-01-01

    The intermediate-sized filaments of vimentin-type (Mr = 57,000) have been identified biochemically and immunochemically as a major cytoskeleton component in the ciliary epithelium of the mammalian eye. When human or rabbit ciliary processes, or cultured ciliary epithelial-derived cells were incubated in serum-free medium containing [ 32 P]orthophosphate and any of the following agents: 1) beta-adrenergic agonists (isoproterenol or epinephrine), 2) direct activators of adenylate cyclase (cholera toxin or forskolin), 3) analogs of cyclic AMP (8-Br-cAMP), or 4) prostaglandin E1, the phosphorylation of vimentin was significantly enhanced. The maximal enhancement ranged, in vivo and in vitro, from about 3-fold in human to 5-fold in rabbit, with either 1 mM 8-Br-cAMP or 0.1 microM forskolin. Indirect immunofluorescence microscopy using a monoclonal antibody, anti-vimentin, allowed the localization of vimentin filaments in cultured ciliary epithelial cells. Treatment of these cells in culture with the catecholamine hormone, isoproterenol (1 microM), resulted in a profound reorganization of vimentin filaments. This may be correlated with the enhanced levels of phosphorylated vimentin observed upon increasing cellular cyclic AMP

  7. Sudden cardiac death in dogs with remodeled hearts is associated with larger beat-to-beat variability of repolarization

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard; Truin, Michiel; van Opstal, Jurren M

    2005-01-01

    Increased proarrhythmia in dogs with chronic AV block (AVB) has been explained by ventricular remodeling causing a decrease in repolarization reserve. Beat-to-beat variability of repolarization (BVR) has been suggested to reflect repolarization reserve, in which high variability represents...... diminished reserve and larger propensity for repolarization-dependent ventricular arrhythmia. A subset of chronic AVB dogs (10%) suffers sudden cardiac death (SCD). With the assumption that repolarization defects constitute a potentially lethal proarrhythmic substrate, we hypothesized that BVR in SCD dogs...... are larger than in matched control chronic AVB dogs. From a population of 200 chronic AVB dogs, initially two groups were chosen retrospectively: 8 dogs that died suddenly (SCD) and 8 control dogs. Control dogs had a longer lifespan after AVB (10 to 18 weeks) than SCD dogs (5 to 10 weeks). All dogs had...

  8. Noninvasive beat-to-beat finger arterial pressure monitoring during orthostasis : a comprehensive review of normal and abnormal responses at different ages

    NARCIS (Netherlands)

    van Wijnen, V K; Finucane, C; Harms, M P M; Nolan, H; Freeman, R L; Westerhof, B. E.; Kenny, R A; Ter Maaten, J C; Wieling, W

    2017-01-01

    Over the past 30years, noninvasive beat-to-beat blood pressure (BP) monitoring has provided great insight into cardiovascular autonomic regulation during standing. Although traditional sphygmomanometric measurement of BP may be sufficient for detection of sustained orthostatic hypotension, it fails

  9. Neural Entrainment and Sensorimotor Synchronization to the Beat in Children with Developmental Dyslexia: An EEG Study

    Directory of Open Access Journals (Sweden)

    Lincoln J. Colling

    2017-07-01

    Full Text Available Tapping in time to a metronome beat (hereafter beat synchronization shows considerable variability in child populations, and individual differences in beat synchronization are reliably related to reading development. Children with developmental dyslexia show impairments in beat synchronization. These impairments may reflect deficiencies in auditory perception of the beat which in turn affect auditory-motor mapping, or may reflect an independent motor deficit. Here, we used a new methodology in EEG based on measuring beat-related steady-state evoked potentials (SS-EPs, Nozaradan et al., 2015 in an attempt to disentangle neural sensory and motor contributions to behavioral beat synchronization in children with dyslexia. Children tapped with both their left and right hands to every second beat of a metronome pulse delivered at 2.4 Hz, or listened passively to the beat. Analyses of preferred phase in EEG showed that the children with dyslexia had a significantly different preferred phase compared to control children in all conditions. Regarding SS-EPs, the groups differed significantly for the passive Auditory listening condition at 2.4 Hz, and showed a trend toward a difference in the Right hand tapping condition at 3.6 Hz (sensorimotor integration measure. The data suggest that neural rhythmic entrainment is atypical in children with dyslexia for both an auditory beat and during sensorimotor coupling (tapping. The data are relevant to a growing literature suggesting that rhythm-based interventions may help language processing in children with developmental disorders of language learning.

  10. Prostanoid Receptors Involved in Regulation of the Beating Rate of Neonatal Rat Cardiomyocytes

    Science.gov (United States)

    Mechiche, Hakima; Grassin-Delyle, Stanislas; Robinet, Arnaud; Nazeyrollas, Pierre; Devillier, Philippe

    2012-01-01

    Although prostanoids are known to be involved in regulation of the spontaneous beating rate of cultured neonatal rat cardiomyocytes, the various subtypes of prostanoid receptors have not been investigated in detail. In our experiments, prostaglandin (PG)F2α and prostanoid FP receptor agonists (fluprostenol, latanoprost and cloprostenol) produced a decrease in the beating rate. Two prostanoid IP receptor agonists (iloprost and beraprost) induced first a marked drop in the beating rate and then definitive abrogation of beating. In contrast, the prostanoid DP receptor agonists (PGD2 and BW245C) and TP receptor agonists (U-46619) produced increases in the beating rate. Sulprostone (a prostanoid EP1 and EP3 receptor agonist) induced marked increases in the beating rate, which were suppressed by SC-19220 (a selective prostanoid EP1 antagonist). Butaprost (a selective prostanoid EP2 receptor agonist), misoprostol (a prostanoid EP2 and EP3 receptor agonist), 11-deoxy-PGE1 (a prostanoid EP2, EP3 and EP4 receptor agonist) did not alter the beating rate. Our results strongly suggest that prostanoid EP1 receptors are involved in positive regulation of the beating rate. Prostanoid EP1 receptor expression was confirmed by western blotting with a selective antibody. Hence, neonatal rat cardiomyocytes express both prostanoid IP and FP receptors (which negatively regulate the spontaneous beating rate) and prostanoid TP, DP1 and EP1 receptors (which positively regulate the spontaneous beating rate). PMID:22984630

  11. Cardiopulmonary Exercise Testing in Fontan Patients With and Without Isomerism (Heterotaxy) as Compared to Patients With Primary Ciliary Dyskinesia and Subjects With Structurally Normal Hearts

    DEFF Research Database (Denmark)

    Loomba, Rohit S; Danduran, Michael; Nielsen, Kim G

    2017-01-01

    with and without isomerism. We have now compared these finding with those from patients with primary ciliary dyskinesia, as many patients with isomerism have ciliary dyskinesia. We identified patients having the Fontan circulation with and without isomerism who had undergone cardiopulmonary exercise testing......, comparing the findings from healthy individuals undergoing exercise, and a comparable number of individuals with primary ciliary dyskinesia but no congenital heart disease. We were able to include a total of 68 patients in our study, with 17 in each of the four groups. Cardiopulmonary exercise testing...

  12. Aerobic fitness in children and young adults with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Madsen, Astrid Hellerup; Green, Kent; Buchvald, Frederik

    2013-01-01

    BACKGROUND: Although aerobic fitness is regarded as an overall prognostic measure of morbidity and mortality, its evaluation in the chronic progressive sinopulmonary disease primary ciliary dyskinesia (PCD) has been infrequently and inconsistently reported. Here we assessed peak oxygen uptake (VO2...... multiple breath inert gas washout (N2 MBW) were assessed in a cross-sectional, single-occasion study of clinically stable children and young adults with PCD. We used a questionnaire including self-reported physical limitations in everyday life or in vigorous activities, and estimation of weekly hours...... patients. CONCLUSION: One-third of PCD patients exhibited substantially lower aerobic fitness than healthy subjects. Aerobic fitness correlated with FEV1, DLCO/VA and self-reported complaints of limitations in vigorous physical activity. These findings are most likely explained by PCD pulmonary disease...

  13. Studies on bicarbonate transporters and carbonic anhydrase in porcine non-pigmented ciliary epithelium

    Science.gov (United States)

    Shahidullah, Mohammad; C-H, To; Pelis, Ryan M.; Delamere, Nicholas A

    2009-01-01

    Purpose Bicarbonate transport plays a role in aqueous humor (AH) secretion. Here, we examined bicarbonate transport mechanisms and carbonic anhydrase (CA) in porcine non-pigmented ciliary epithelium (NPE). Methods Cytoplasmic pH (pHi) was measured in cultured porcine NPE loaded with BCECF. Anion exchanger (AE), sodium bicarbonate cotransporter (NBC) and CA were examined by RT-PCR and immunolocalization. AH secretion was measured in the intact porcine eye using a fluorescein dilution technique. Results Anion exchanger AE2, CAII and CAIV were abundant in the NPE layer. In cultured NPE superfused with a CO2/HCO3− free HEPES buffer, exposure to a CO2/HCO3−-containing buffer caused a rapid acidification followed by a gradual pHi increase. Subsequent removal of CO2/HCO3− with HEPES buffer caused rapid alkalinization followed by gradual pHi decrease. The rate of gradual alkalinization after addition of HCO3−/CO2 was inhibited by sodium-free conditions, DIDS, CA inhibitors acetazolamide and methazolamide but not by Na-H exchange inhibitor dimethylamiloride or low chloride buffer. The phase of gradual acidification after removal of HCO3−/CO2 was inhibited by DIDS, acetazolamide, methazolamide and by low chloride buffer. DIDS reduced baseline pHi. In the intact eye, DIDS and acetazolamide reduced AH secretion by 25% and 44% respectively. Conclusion The results suggest the NPE uses a Na+-HCO3− cotransporter to import bicarbonate and a Cl−/HCO3− exchanger to export bicarbonate. CA influences the rate of bicarbonate transport. AE2, CAII and CAIV are enriched in the NPE layer of the ciliary body and their coordinated function may contribute to AH secretion by effecting bicarbonate transport into the eye. PMID:19011010

  14. Induction of Functional 3D Ciliary Epithelium-Like Structure From Mouse Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Kinoshita, Hirofumi; Suzuma, Kiyoshi; Kaneko, Jun; Mandai, Michiko; Kitaoka, Takashi; Takahashi, Masayo

    2016-01-01

    To generate ciliary epithelium (CE) from mouse induced pluripotent stem (iPS) cells. Recently, a protocol for self-organizing optic cup morphogenesis in three-dimensional culture was reported, and it was suggested that ocular tissue derived from neural ectoderm could be differentiated. We demonstrated that a CE-like double-layered structure could be induced in simple culture by using a modified Eiraku differentiation protocol. Differentiation of a CE-like double-layered structure could be promoted by glycogen synthase kinase 3β (GSK-3β) inhibitor. Connexin43 and aquaporin1 were expressed in both thin layers, and induced CE-like cells expressed ciliary marker genes, such as cyclinD2, zic1, tgfb2, aldh1a3, wfdc1, otx1, BMP4, and BMP7. Increases in cytoplasmic and nuclear β-catenin in aggregates of the CE-like double-layered structure were confirmed by Western blot analysis. In addition, tankyrase inhibitor prevented the induction of the CE-like double-layered structure by GSK-3β inhibitor. Dye movement from pigmented cells to nonpigmented cells in the mouse iPS cell-derived CE-like structure was observed in a fluid movement experiment, consistent with the physiological function of CE in vivo. We could differentiate CE from mouse iPS cells in the present study. In the future, we hope that this CE-like complex will become useful as a graft for transplantation therapy in pathologic ocular hypotension due to CE dysfunction, and as a screening tool for the development of drugs for diseases associated with CE function.

  15. Disruption of a Ciliary B9 Protein Complex Causes Meckel Syndrome

    Science.gov (United States)

    Dowdle, William E.; Robinson, Jon F.; Kneist, Andreas; Sirerol-Piquer, M. Salomé; Frints, Suzanna G.M.; Corbit, Kevin C.; Zaghloul, Norran A.; van Lijnschoten, Gesina; Mulders, Leon; Verver, Dideke E.; Zerres, Klaus; Reed, Randall R.; Attié-Bitach, Tania; Johnson, Colin A.; García-Verdugo, José Manuel; Katsanis, Nicholas; Bergmann, Carsten; Reiter, Jeremy F.

    2011-01-01

    Nearly every ciliated organism possesses three B9 domain-containing proteins: MKS1, B9D1, and B9D2. Mutations in human MKS1 cause Meckel syndrome (MKS), a severe ciliopathy characterized by occipital encephalocele, liver ductal plate malformations, polydactyly, and kidney cysts. Mouse mutations in either Mks1 or B9d2 compromise ciliogenesis and result in phenotypes similar to those of MKS. Given the importance of these two B9 proteins to ciliogenesis, we examined the role of the third B9 protein, B9d1. Mice lacking B9d1 displayed polydactyly, kidney cysts, ductal plate malformations, and abnormal patterning of the neural tube, concomitant with compromised ciliogenesis, ciliary protein localization, and Hedgehog (Hh) signal transduction. These data prompted us to screen MKS patients for mutations in B9D1 and B9D2. We identified a homozygous c.301A>C (p.Ser101Arg) B9D2 mutation that segregates with MKS, affects an evolutionarily conserved residue, and is absent from controls. Unlike wild-type B9D2 mRNA, the p.Ser101Arg mutation failed to rescue zebrafish phenotypes induced by the suppression of b9d2. With coimmunoprecipitation and mass spectrometric analyses, we found that Mks1, B9d1, and B9d2 interact physically, but that the p.Ser101Arg mutation abrogates the ability of B9d2 to interact with Mks1, further suggesting that the mutation compromises B9d2 function. Our data indicate that B9d1 is required for normal Hh signaling, ciliogenesis, and ciliary protein localization and that B9d1 and B9d2 are essential components of a B9 protein complex, disruption of which causes MKS. PMID:21763481

  16. No evidence of cholesteatoma in untreated otitis media with effusion in children with primary ciliary dyskinesia.

    Science.gov (United States)

    Ghedia, Reshma; Ahmed, Jahangir; Navaratnam, Annakan; Harcourt, Jonny

    2018-02-01

    Primary Ciliary Dyskinesia (PCD) describes a group of inherited disorders that result in abnormal ciliary motion leading to mucous stasis. Clinical features include almost universally otitis media with effusion (OME), particularly in infants. PCD patients provide us with a cohort of patients with OME that is not treated with ventilatory tube (VT) insertion as these have been shown to result in frequent complications including chronic otorrhoea, early extrusion and persistent perforation without significant improvement to hearing in the long term. This cohort was used to investigate whether children with PCD and OME not treated with VT were predisposed to cholesteatoma formation in the setting of a paediatric quaternary referral centre. A retrospective chart review was performed of all the children attending a multi-disciplinary PCD clinic at a national quaternary referral centre with a diagnosis of OME. We reviewed otoscopic findings, and audiometry and tympanometry results. We assessed the children in four groups: Watchful waiting, hearing aids, VT, and VT and hearing aids. One-hundred-and-one of 107 patients included in the study had a diagnosis of otitis media with effusion. No child with OME and PCD was diagnosed with a cholesteatoma during the follow up period. The only children who had insertion of a ventilatory tube were those who had the procedure prior to the formal diagnosis of PCD. We found a significant complication rate in the children with VT insertion. Hearing improved over time. The prevalence of retraction pockets in untreated OME was 1.72% (3 out of 174 ears). In children with PCD, OME is an almost universal finding in younger children, but not in adolescents. The study supports the current preference to avoid VT insertion in children with PCD as it confers a significantly higher rate of complications. No cases of cholesteatoma were found in this cohort of PCD children with OME managed without VTs. Crown Copyright © 2017. Published by Elsevier B

  17. Localization of multidrug resistance-associated protein 2 in the nonpigmented ciliary epithelium of the eye.

    Science.gov (United States)

    Pelis, Ryan M; Shahidullah, Mohammad; Ghosh, Sikha; Coca-Prados, Miguel; Wright, Stephen H; Delamere, Nicholas A

    2009-05-01

    The nonpigmented epithelium (NPE) of the ciliary body represents an important component of the blood-aqueous barrier of the eye. Many therapeutic drugs penetrate poorly across the NPE into the aqueous humor of the eye interior. Several of these therapeutic drugs, such as methotrexate, vincristine, and etoposide, are substrates of the multidrug resistance-associated protein 2 (MRP2). Abundant MRP2 protein was detected by Western blot in homogenates of human ciliary body and freshly dissected porcine NPE. In cultured porcine NPE, the intracellular accumulation of the MRP2 substrates calcein (1.8-fold), 5-(and-6)-carboxy-2',7'-dichlorofluorescein (22.1-fold), and doxorubicin (1.9-fold) was significantly increased in the presence of 50 microM MK571 ((E)-3-[[[3-[2-(7-chloro-2-quinolinyl)-ethenyl]phenyl]-[[3-dimethylamino)-3-oxopropyl]thio]methyl]thio]-propanoic acid), an MRP inhibitor. In addition, the intracellular accumulation of the MRP2 substrate glutathione methylfluorescein was increased by 50 microM MK571 (4.3-fold), 500 microM indomethacin (2.6-fold), and 50 microM cyclosporin A (2.1-fold) but not by 500 microM sulfinpyrazone. These data are consistent with MRP2-mediated transport activity in cultured NPE, and MRP2 mRNA (reverse transcriptase-polymerase chain reaction) and protein (Western blot) were detected in the cultured cells. Immunolocalization studies in native human and porcine eyes showed MRP2 protein at the apical interface of the NPE and pigmented cell layers. Close examination of MRP2 immunoreactivity supported the conclusion that MRP2 is localized in the apical membrane of the NPE. MRP2 at the apical membrane of NPE cells may be involved in protecting intraocular tissues from exposure to potentially harmful toxins.

  18. Gaussian-state entanglement in a quantum beat laser

    International Nuclear Information System (INIS)

    Tahira, Rabia; Ikram, Manzoor; Nha, Hyunchul; Zubairy, M. Suhail

    2011-01-01

    Recently quantum beat lasers have been considered as a source of entangled radiation [S. Qamar, F. Ghafoor, M. Hillery, and M. S. Zubairy, Phys. Rev. A 77, 062308 (2008)]. We investigate and quantify the entanglement of this system when the initial cavity modes are prepared in a Gaussian two-mode state, one being a nonclassical state and the other a thermal state. It is investigated how the output entanglement varies with the nonclassicality of the input Gaussian state, thermal noise, and the strength of the driving field.

  19. Wife beating amongst Africans as a challenge to pastoral care

    Directory of Open Access Journals (Sweden)

    Magezi E. Baloyi

    2013-11-01

    Full Text Available Traditional African people are known for respecting their marriage. Even though marriage is so highly regarded, it is astonishing to realise that wife beating has become an extremely common practice amongst them. It therefore becomes an important research question to ask about the extent to which deeply-seated traditional customs regarding wife beating as a form of stamping down authority and of trying to keep the household in order, will have to be confronted with what is deemed to be good practice from the perspective of the law, community and pastoral caregivers. There are women who live with scars on their faces and bodies, having been beaten by their husbands. Although there are many forms of abuse towards women in family situations, this article aims particularly to focus on wife beating that is practiced for traditional as well as other related reasons. This research will involve itself with establishing whether the reasons for wife beating are part of the traditional system for keeping the household in order and interrogate both legal and pastoral interventions that attempt to eliminate or avoid such behaviour. Tradisionele Afrikane is nog altyd daarvoor bekend dat hulle die instelling van die huwelik respekteer. Verbasend genoeg is vroueslanery egter ’n ou gevestigde gebruik wat vandag algemeen onder Afrikane voorkom. Die mate waartoe diepgewortelde gebruike soos vroueslanery as ’n manier om gesag af te dwing en orde in die huis te handhaaf, gekonfronteer sal moet word met wat as goeie praktyk beskou word vanuit die gesigspunt van die reg, die gemeenskap en pastorale versorgers, is dus ’n belangrike navorsingsvraag. Baie vroue dra fisiese en emosionele littekens wat deur hulle eggenote veroorsaak is. Alhoewel daar baie vorme van vrouemishandeling in familiesituasies voorkom, fokus hierdie artikel veral op vroueslanery wat om tradisionele en verwante redes beoefen word. Hierdie navorsing probeer vasstel of die redes vir

  20. Individual differences in beat perception affect gait responses to low- and high-groove music.

    Directory of Open Access Journals (Sweden)

    Li-Ann eLeow

    2014-10-01

    Full Text Available Slowed gait in Parkinson’s disease (PD patients can be improved when patients synchronize footsteps to isochronous metronome cues, but limited retention of such improvements suggest that permanent cueing regimes are needed for long-term improvements. If so, music might make permanent cueing regimes more pleasant, improving adherence; however, music cueing requires patients to synchronize movements to the beat, which might be difficult for PD patients who tend to show weak beat perception. One solution may be to use high groove music, which has high beat salience that may facilitate synchronization, and affective properties which may improve motivation to move. As a first step in understanding how beat perception affects gait in complex neurological disorders, we examined how beat perception ability affected gait in neurotypical adults. Synchronization performance and gait parameters were assessed as healthy young adults with strong or weak beat perception synchronized to low groove music, high groove music, and metronome cues. High groove music was predicted to elicit better synchronization than low groove music, due to its higher beat salience. Two musical tempi, or rates, were used: (1 preferred tempo: beat rate matched to preferred step rate and (2 faster tempo: beat rate adjusted to 22.5% faster than preferred step rate. For both strong and weak beat-perceivers, synchronization performance was best with metronome cues, followed by high groove music, and worst with low groove music. In addition, high groove music elicited longer and faster steps than low groove music, both at preferred tempo and at faster tempo. Low groove music was particularly detrimental to gait in weak beat-perceivers, who showed slower and shorter steps compared to uncued walking. The findings show that individual differences in beat perception affect gait when synchronizing footsteps to music, and have implications for using music in gait rehabilitation.

  1. Individual Differences in Beat Perception Affect Gait Responses to Low- and High-Groove Music

    Science.gov (United States)

    Leow, Li-Ann; Parrott, Taylor; Grahn, Jessica A.

    2014-01-01

    Slowed gait in patients with Parkinson’s disease (PD) can be improved when patients synchronize footsteps to isochronous metronome cues, but limited retention of such improvements suggest that permanent cueing regimes are needed for long-term improvements. If so, music might make permanent cueing regimes more pleasant, improving adherence; however, music cueing requires patients to synchronize movements to the “beat,” which might be difficult for patients with PD who tend to show weak beat perception. One solution may be to use high-groove music, which has high beat salience that may facilitate synchronization, and affective properties, which may improve motivation to move. As a first step to understanding how beat perception affects gait in complex neurological disorders, we examined how beat perception ability affected gait in neurotypical adults. Synchronization performance and gait parameters were assessed as healthy young adults with strong or weak beat perception synchronized to low-groove music, high-groove music, and metronome cues. High-groove music was predicted to elicit better synchronization than low-groove music, due to its higher beat salience. Two musical tempi, or rates, were used: (1) preferred tempo: beat rate matched to preferred step rate and (2) faster tempo: beat rate adjusted to 22.5% faster than preferred step rate. For both strong and weak beat-perceivers, synchronization performance was best with metronome cues, followed by high-groove music, and worst with low-groove music. In addition, high-groove music elicited longer and faster steps than low-groove music, both at preferred tempo and at faster tempo. Low-groove music was particularly detrimental to gait in weak beat-perceivers, who showed slower and shorter steps compared to uncued walking. The findings show that individual differences in beat perception affect gait when synchronizing footsteps to music, and have implications for using music in gait rehabilitation. PMID:25374521

  2. Enhanced timing abilities in percussionists generalize to rhythms without a musical beat.

    Science.gov (United States)

    Cameron, Daniel J; Grahn, Jessica A

    2014-01-01

    The ability to entrain movements to music is arguably universal, but it is unclear how specialized training may influence this. Previous research suggests that percussionists have superior temporal precision in perception and production tasks. Such superiority may be limited to temporal sequences that resemble real music or, alternatively, may generalize to musically implausible sequences. To test this, percussionists and nonpercussionists completed two tasks that used rhythmic sequences varying in musical plausibility. In the beat tapping task, participants tapped with the beat of a rhythmic sequence over 3 stages: finding the beat (as an initial sequence played), continuation of the beat (as a second sequence was introduced and played simultaneously), and switching to a second beat (the initial sequence finished, leaving only the second). The meters of the two sequences were either congruent or incongruent, as were their tempi (minimum inter-onset intervals). In the rhythm reproduction task, participants reproduced rhythms of four types, ranging from high to low musical plausibility: Metric simple rhythms induced a strong sense of the beat, metric complex rhythms induced a weaker sense of the beat, nonmetric rhythms had no beat, and jittered nonmetric rhythms also had no beat as well as low temporal predictability. For both tasks, percussionists performed more accurately than nonpercussionists. In addition, both groups were better with musically plausible than implausible conditions. Overall, the percussionists' superior abilities to entrain to, and reproduce, rhythms generalized to musically implausible sequences.

  3. Enhanced Timing Abilities in Percussionists Generalize to Rhythms Without a Musical Beat

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2014-12-01

    Full Text Available The ability to entrain movements to music is arguably universal, but it is unclear how specialized training may influence this. Previous research suggests that percussionists have superior temporal precision in perception and production tasks. Such superiority may be limited to temporal sequences that resemble real music or, alternatively, may generalize to musically implausible sequences. To test this, percussionists and nonpercussionists completed two tasks that used rhythmic sequences varying in musical plausibility. In the beat tapping task, participants tapped with the beat of a rhythmic sequence over 3 stages: finding the beat (as an initial sequence played, continuation of the beat (as a second sequence was introduced and played simultaneously, and switching to a second beat (the initial sequence finished, leaving only the second. The metres of the two sequences were either congruent or incongruent, as were their tempi (minimum inter-onset intervals. In the rhythm reproduction task, participants reproduced rhythms of four types, ranging from high to low musical plausibility: Metric simple rhythms induced a strong sense of the beat, metric complex rhythms induced a weaker sense of the beat, nonmetric rhythms had no beat, and jittered nonmetric rhythms also had no beat as well as low temporal predictability. For both tasks, percussionists performed more accurately than nonpercussionists. In addition, both groups were better with musically plausible than implausible conditions. Overall, the percussionists’ superior abilities to entrain to, and reproduce, rhythms generalized to musically implausible sequences.

  4. PEP-II Beta Beat Fixes with MIA

    International Nuclear Information System (INIS)

    Yan, Y

    2004-01-01

    We first find a virtual accelerator for the HER or the LER through determination of all quadrupole strengths and sextupole feed-downs as well as all BPM gains and BPM cross-plane couplings by an SVD-enhanced Least-squares fitting of the quantities derivable from a complete set of orbits. These quantities are the phase advances, the Green's functions, and the tilt angles and axis ratios of the coupling eigen ellipses. They are obtained by analyzing turn-by-turn Beam Position Monitor (BPM) data with a high-resolution model-independent analysis (MIA). Once the virtual accelerator is found, we select a limited number of key quadrupoles, for example, the linear trombone quadrupoles and the global skews, for Least-square fitting of their strengths to minimize the beta beat while keeping other optics characters unchanged if not improved. We then dial in these limited number of quadrupole strength changes to the real accelerator (HER or LER) to achieve a better-performance PEP-II. Noticeable achievement by this MIA technique has been that MIA has helped PEP-II achieve its breaking record peak luminosity of 6.5 x 10 33 cm -2 s -1 in 2003 by bringing the LER working tune to near half integer and simultaneously fixing the beta beat, which would, otherwise, be difficult without MIA because of the strong LER coupling effect

  5. Cardioscopic tricuspid valve repair in a beating ovine heart.

    Science.gov (United States)

    Umakanthan, Ramanan; Ghanta, Ravi K; Rangaraj, Aravind T; Lee, Lawrence S; Laurence, Rita G; Fox, John A; Mihaljevic, Tomislav; Bolman, Ralph M; Cohn, Lawrence H; Chen, Frederick Y

    2009-04-01

    Open heart surgery is commonly associated with cardiopulmonary bypass and cardioplegic arrest. The attendant risks of cardiopulmonary bypass may be prohibitive in high-risk patients. We present a novel endoscopic technique of performing tricuspid valve repair without cardiopulmonary bypass in a beating ovine heart. Six sheep underwent sternotomy and creation of a right heart shunt to eliminate right atrial and right ventricular blood for clear visualization. The superior vena cava, inferior vena cava, pulmonary artery, and coronary sinus were cannulated, and the blood flow from these vessels was shunted into the pulmonary artery via a roller pump. The posterior leaflet of the tricuspid valve was partially excised to create tricuspid regurgitation, which was confirmed by Doppler echocardiography. A 7.0-mm fiberoptic videoscope was inserted into the right atrium to visualize the tricuspid valve. Under cardioscopic vision, an endoscopic needle driver was inserted into the right atrium, and a concentric stitch was placed along the posterior annulus to bicuspidize the tricuspid valve. Doppler echocardiography confirmed reduction of tricuspid regurgitation. All animals successfully underwent and tolerated the surgical procedure. The right heart shunt generated a bloodless field, facilitating cardioscopic tricuspid valve visualization. The endoscopic stitch resulted in annular plication and functional tricuspid valve bicuspidization, significantly reducing the degree of tricuspid regurgitation. Cardioscopy enables less invasive, beating-heart tricuspid valve surgery in an ovine model. This technique may be useful in performing right heart surgery without cardiopulmonary bypass in high-risk patients.

  6. Efficient heart beat detection using embedded system electronics

    Science.gov (United States)

    Ramasamy, Mouli; Oh, Sechang; Varadan, Vijay K.

    2014-04-01

    The present day bio-technical field concentrates on developing various types of innovative ambulatory and wearable devices to monitor several bio-physical, physio-pathological, bio-electrical and bio-potential factors to assess a human body's health condition without intruding quotidian activities. One of the most important aspects of this evolving technology is monitoring heart beat rate and electrocardiogram (ECG) from which many other subsidiary results can be derived. Conventionally, the devices and systems consumes a lot of power since the acquired signals are always processed on the receiver end. Because of this back end processing, the unprocessed raw data is transmitted resulting in usage of more power, memory and processing time. This paper proposes an innovative technique where the acquired signals are processed by a microcontroller in the front end of the module and just the processed signal is then transmitted wirelessly to the display unit. Therefore, power consumption is considerably reduced and clearer data analysis is performed within the module. This also avoids the need for the user to be educated about usage of the device and signal/system analysis, since only the number of heart beats will displayed at the user end. Additionally, the proposed concept also eradicates the other disadvantages like obtrusiveness, high power consumption and size. To demonstrate the above said factors, a commercial controller board was used to extend the monitoring method by using the saved ECG data from a computer.

  7. Clinical value of measurement of pulmonary radioaerosol mucociliary clearance in the work up of primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Munkholm, Mathias; Nielsen, Kim Gjerum; Mortensen, Jann

    2015-01-01

    BACKGROUND: We aimed to evaluate and define the general clinical applicability and impact of pulmonary radioaerosol mucociliary clearance (PRMC) on the work up of patients suspected of having primary ciliary dyskinesia (PCD). In addition, we wanted to evaluate the accuracy of the reference values...... primarily to results from nasal ciliary function testing, to electron microscopic (EM) examination of the ultrastructure of the cilia, and to the final clinical diagnosis. RESULTS: Of the 239 patients, 27 ended up with a final clinical diagnosis of definitive PCD. No patients with a PRMC test...... of the entire lung. Its greatest strength is its ability to reject a suspected PCD diagnosis with great certainty. In our material, this accounted for 2/3 of referred patients. In addition, the test has a high rate of conclusive results. According to our analyses, reference equations on children would benefit...

  8. Long-term outcomes of ciliary sulcus versus capsular bag fixation of intraocular lenses in children: An ultrasound biomicroscopy study.

    Directory of Open Access Journals (Sweden)

    Yun-E Zhao

    Full Text Available To evaluate the long-term outcomes of ciliary sulcus versus capsular bag fixation of intraocular lenses (IOLs in children after pediatric cataract surgery.IOL was implanted in the ciliary sulcus in 21 eyes of 14 children, and in the capsular bag in 19 eyes of 12 children for the treatment of pediatric cataract in an institutional setting. Ultrasound biomicroscopy (UBM was performed. Main outcome measures included IOL decentration, IOL tilt, anterior chamber depth (ACD, angle-opening distance at 500 μm (AOD500, trabecular-iris angle (TIA, best-corrected visual acuity (BCVA, intraocular pressure (IOP, and incidence of postoperative complications.The mean follow-up period was 6.81 ± 1.82 years. Comparing to the capsular bag fixation group, the ciliary sulcus fixation group had higher vertical IOL decentration, horizontal IOL tilt, and vertical IOL tilt (p = 0.02, 0.01,0.01, respectively, higher incidence of iris-IOL contact and peripheral anterior synechia (p = 0.001, 0.03, respectively, smaller ACD, AOD500, and TIA (p = 0.02, 0.03, 0.04, respectively, higher mean IOP (17.10 ±6.06 mmHg vs.14.15± 4.74 mmHg, p = 0.01, and higher incidence of secondary glaucoma (28.57% vs. 10.53%, p = 0.007.There was no significant difference between the two groups with regard to the BCVA, refractive errors, incidence of myopic shift, nystagmus, strabismus, and visual axis opacity.Ciliary sulcus fixation of IOLs in pediatric eyes may increase IOL malposition and crowding of the anterior segment, and may associate with a higher risk of secondary glaucoma compared to capsular bag fixation of IOLs.

  9. Localization of a guanylyl cyclase to chemosensory cilia requires the novel ciliary MYND domain protein DAF-25.

    Directory of Open Access Journals (Sweden)

    Victor L Jensen

    2010-11-01

    Full Text Available In harsh conditions, Caenorhabditis elegans arrests development to enter a non-aging, resistant diapause state called the dauer larva. Olfactory sensation modulates the TGF-β and insulin signaling pathways to control this developmental decision. Four mutant alleles of daf-25 (abnormal DAuer Formation were isolated from screens for mutants exhibiting constitutive dauer formation and found to be defective in olfaction. The daf-25 dauer phenotype is suppressed by daf-10/IFT122 mutations (which disrupt ciliogenesis, but not by daf-6/PTCHD3 mutations (which prevent environmental exposure of sensory cilia, implying that DAF-25 functions in the cilia themselves. daf-25 encodes the C. elegans ortholog of mammalian Ankmy2, a MYND domain protein of unknown function. Disruption of DAF-25, which localizes to sensory cilia, produces no apparent cilia structure anomalies, as determined by light and electron microscopy. Hinting at its potential function, the dauer phenotype, epistatic order, and expression profile of daf-25 are similar to daf-11, which encodes a cilium-localized guanylyl cyclase. Indeed, we demonstrate that DAF-25 is required for proper DAF-11 ciliary localization. Furthermore, the functional interaction is evolutionarily conserved, as mouse Ankmy2 interacts with guanylyl cyclase GC1 from ciliary photoreceptors. The interaction may be specific because daf-25 mutants have normally-localized OSM-9/TRPV4, TAX-4/CNGA1, CHE-2/IFT80, CHE-11/IFT140, CHE-13/IFT57, BBS-8, OSM-5/IFT88, and XBX-1/D2LIC in the cilia. Intraflagellar transport (IFT (required to build cilia is not defective in daf-25 mutants, although the ciliary localization of DAF-25 itself is influenced in che-11 mutants, which are defective in retrograde IFT. In summary, we have discovered a novel ciliary protein that plays an important role in cGMP signaling by localizing a guanylyl cyclase to the sensory organelle.

  10. Sonic Hedgehog dependent phosphorylation by CK1α and GRK2 is required for ciliary accumulation and activation of smoothened.

    Directory of Open Access Journals (Sweden)

    Yongbin Chen

    2011-06-01

    Full Text Available Hedgehog (Hh signaling regulates embryonic development and adult tissue homeostasis through the GPCR-like protein Smoothened (Smo, but how vertebrate Smo is activated remains poorly understood. In Drosophila, Hh dependent phosphorylation activates Smo. Whether this is also the case in vertebrates is unclear, owing to the marked sequence divergence between vertebrate and Drosophila Smo (dSmo and the involvement of primary cilia in vertebrate Hh signaling. Here we demonstrate that mammalian Smo (mSmo is activated through multi-site phosphorylation of its carboxyl-terminal tail by CK1α and GRK2. Phosphorylation of mSmo induces its active conformation and simultaneously promotes its ciliary accumulation. We demonstrate that graded Hh signals induce increasing levels of mSmo phosphorylation that fine-tune its ciliary localization, conformation, and activity. We show that mSmo phosphorylation is induced by its agonists and oncogenic mutations but is blocked by its antagonist cyclopamine, and efficient mSmo phosphorylation depends on the kinesin-II ciliary motor. Furthermore, we provide evidence that Hh signaling recruits CK1α to initiate mSmo phosphorylation, and phosphorylation further increases the binding of CK1α and GRK2 to mSmo, forming a positive feedback loop that amplifies and/or sustains mSmo phosphorylation. Hence, despite divergence in their primary sequences and their subcellular trafficking, mSmo and dSmo employ analogous mechanisms for their activation.

  11. Short Communication: An apospory-specific genomic region is conserved between Buffelgrass (Cenchrus ciliaris L.) and Pennisetum squamulatum Fresen.

    Science.gov (United States)

    Roche; Cong; Chen; Hanna; Gustine; Sherwood; Ozias-Akins

    1999-07-01

    Twelve molecular markers linked to pseudogamous apospory, a form of gametophytic apomixis, were previously isolated from Pennisetum squamulatum Fresen. No recombination between these markers was found in a segregating population of 397 individuals (Ozias-Akins et al. 1998, Proc. Natl Acad. Sci. USA, 95, 5127-5132). The objective of the present study was to test if these markers were also linked to the aposporous mode of reproduction in two small segregating populations of Cenchrus ciliaris (= Pennisetum ciliare (L.)Link), another apomictic grass species. Among 12 markers (sequence characterized amplified regions, SCARs), six were scored as dominant markers between aposporous and sexual C. ciliaris genotypes (presence/absence, respectively). Five were always linked to apospory and one showed a low level of recombination in 84 progenies. Restriction fragment length polymorphisms (RFLPs) were observed between sexual and apomictic phenotypes for three of the six remaining SCARs from P. squamulatum when used as probes. No recombination was observed in the F1 progenies. Preliminary data from megabase DNA analysis and sequencing in both species indicate that an apospory-specific genomic region (ASGR) is highly conserved between the two species. Although C. ciliaris has a smaller genome size to P. squamulatum, a higher copy number for markers linked to apospory found in the former may impair the progress of positional cloning of gene(s) for apomixis in this species.

  12. (/sup 3/H)ouabain localization of Na-K ATPase in the epithelium of rabbit ciliary body pars plicata

    Energy Technology Data Exchange (ETDEWEB)

    Usukura, J.; Fain, G.L.; Bok, D.

    1988-04-01

    The secretion of the aqueous humor has been proposed to occur as the result of active Na+ transport by a ouabain-sensitive Na-K ATPase. We have examined the localization of this enzyme in the epithelium of rabbit ciliary body pars plicata using (3H)ouabain autoradiography. Single ciliary processes were isolated and incubated in Ringer containing (3H)ouabain. Processes were then rapidly frozen, freezedried, sectioned and exposed for autoradiography. In the light microscope, silver grains were found predominantly over the nonpigmented epithelial cells. In the electron microscope, grains could be localized for the most part to the interdigitations of the nonpigmented cell basolateral membrane. Label could also be observed at a much lower density above other membranes and above the pigmented and nonpigmented cell cytoplasm. No label was found in sections of control tissue which had been incubated in (3H)ouabain with an excess of cold ouabain. To show that the (3H)ouabain had free access to all of the membrane surfaces within the epithelium, in parallel experiments we incubated isolated processes in horseradish peroxidase. Our experiments suggest that most of the active Na+ transport in ciliary body epithelium occurs across the basolateral membrane of nonpigmented cells into the posterior chamber. Furthermore, the placement of the Na-K ATPase within the narrow membrane infoldings of the interdigitations is consistent with a role for this enzyme in water transport and the production of the aqueous.

  13. OFD1, as a Ciliary Protein, Exhibits Neuroprotective Function in Photoreceptor Degeneration Models.

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    Juan Wang

    Full Text Available Ofd1 is a newly identified causative gene for Retinitis pigmentosa (RP, a photoreceptor degenerative disease. This study aimed to examine Ofd1 localization in retina and further to investigate its function in photoreceptor degeneration models. Ofd1 localization in rat retina was examined using immunofluorescence. N-methyl-N-nitrosourea (MNU-induced rats and Royal College of Surgeons (RCS rats were used as photoreceptor degeneration models. The expression pattern of Ofd1, other ciliary associated genes and Wnt signaling pathway genes were examined in rat models. Furthermore, pEGFP-Ofd1-CDS and pSUPER-Ofd1-shRNA were constructed to overexpress and knockdown the expression level in 661W and R28 cells. MNU was also used to induce cell death. Cilia formation was observed using immunocytochemistry (ICC. Reactive oxygen species (ROS were detected using the 2', 7'-Dichlorofluorescin diacetate (DCFH-DA assay. Apoptosis genes expression was examined using qRT-PCR, Western blotting and fluorescence-activated cell sorting (FACS. Ofd1 localized to outer segments of rat retina photoreceptors. Ofd1 and other ciliary proteins expression levels increased from the 1st and 4th postnatal weeks and decreased until the 6th week in the RCS rats, while their expression consistently decreased from the 1st and 7th day in the MNU rats. Moreover, Wnt signaling pathway proteins expression was significantly up-regulated in both rat models. Knockdown of Ofd1 expression resulted in a smaller population, shorter length of cell cilia, and lower cell viability. Ofd1 overexpression partially attenuated MNU toxic effects by reducing ROS levels and mitigating apoptosis. To the best of our knowledge, this is the first study demonstrating Ofd1 localization and its function in rat retina and in retinal degeneration rat models. Ofd1 plays a role in controlling photoreceptor cilium length and number. Importantly, it demonstrates a neuroprotective function by protecting the photoreceptor

  14. Acute versus chronic loss of mammalian Azi1/Cep131 results in distinct ciliary phenotypes.

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    Emma A Hall

    Full Text Available Defects in cilium and centrosome function result in a spectrum of clinically-related disorders, known as ciliopathies. However, the complex molecular composition of these structures confounds functional dissection of what any individual gene product is doing under normal and disease conditions. As part of an siRNA screen for genes involved in mammalian ciliogenesis, we and others have identified the conserved centrosomal protein Azi1/Cep131 as required for cilia formation, supporting previous Danio rerio and Drosophila melanogaster mutant studies. Acute loss of Azi1 by knock-down in mouse fibroblasts leads to a robust reduction in ciliogenesis, which we rescue by expressing siRNA-resistant Azi1-GFP. Localisation studies show Azi1 localises to centriolar satellites, and traffics along microtubules becoming enriched around the basal body. Azi1 also localises to the transition zone, a structure important for regulating traffic into the ciliary compartment. To study the requirement of Azi1 during development and tissue homeostasis, Azi1 null mice were generated (Azi1(Gt/Gt. Surprisingly, Azi1(Gt/Gt MEFs have no discernible ciliary phenotype and moreover are resistant to Azi1 siRNA knock-down, demonstrating that a compensation mechanism exists to allow ciliogenesis to proceed despite the lack of Azi1. Cilia throughout Azi1 null mice are functionally normal, as embryonic patterning and adult homeostasis are grossly unaffected. However, in the highly specialised sperm flagella, the loss of Azi1 is not compensated, leading to striking microtubule-based trafficking defects in both the manchette and the flagella, resulting in male infertility. Our analysis of Azi1 knock-down (acute loss versus gene deletion (chronic loss suggests that Azi1 plays a conserved, but non-essential trafficking role in ciliogenesis. Importantly, our in vivo analysis reveals Azi1 mediates novel trafficking functions necessary for flagellogenesis. Our study highlights the

  15. Binaural interaction in low-frequency neurons in inferior colliculus of the cat. II. Effects of changing rate and direction of interaural phase.

    Science.gov (United States)

    Yin, T C; Kuwada, S

    1983-10-01

    We used the binaural beat stimulus to study the interaural phase sensitivity of inferior colliculus (IC) neurons in the cat. The binaural beat, produced by delivering tones of slightly different frequencies to the two ears, generates continuous and graded changes in interaural phase. Over 90% of the cells that exhibit a sensitivity to changes in the interaural delay also show a sensitivity to interaural phase disparities with the binaural beat. Cells respond with a burst of impulses with each complete cycle of the beat frequency. The period histogram obtained by binning the poststimulus time histogram on the beat frequency gives a measure of the interaural phase sensitivity of the cell. In general, there is good correspondence in the shapes of the period histograms generated from binaural beats and the interaural phase curves derived from interaural delays and in the mean interaural phase angle calculated from them. The magnitude of the beat frequency determines the rate of change of interaural phase and the sign determines the direction of phase change. While most cells respond in a phase-locked manner up to beat frequencies of 10 Hz, there are some cells tht will phase lock up to 80 Hz. Beat frequency and mean interaural phase angle are linearly related for most cells. Most cells respond equally in the two directions of phase change and with different rates of change, at least up to 10 Hz. However, some IC cells exhibit marked sensitivity to the speed of phase change, either responding more vigorously at low beat frequencies or at high beat frequencies. In addition, other cells demonstrate a clear directional sensitivity. The cells that show sensitivity to the direction and speed of phase changes would be expected to demonstrate a sensitivity to moving sound sources in the free field. Changes in the mean interaural phase of the binaural beat period histograms are used to determine the effects of changes in average and interaural intensity on the phase sensitivity

  16. Recent invasion of buffel grass (Cenchrus ciliaris of a natural protected area from the southern Sonoran Desert Invasión reciente de zacate buffel (Cenchrus ciliaris en un área natural protegida del desierto sonorense

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    Erick De la Barrera

    2008-12-01

    Full Text Available The Centro Ecológico de Sonora is a natural protected area where the natural vegetation remained undisturbed at least until 1997. Since then, Cenchrus ciliaris has become a prominent element of the vegetation because of disturbance. Climate, soil properties, population structure and biological activity for C. ciliaris were studied to gain understanding of the ecological mechanisms that favored the invasion by this exotic grass. Mean air temperature and annual rainfall were 24.8°C and 302 mm. The soil was a loamy-sand that was poor in most nutrients, but particularly rich in phosphorus. Pennisetum ciliare was the most abundant species at the Centro Ecológico, representing over one third of total plant ground cover. Basal area for individual plants ranged from less than 1 cm² to almost 1 m². Living leaves per plant increased with precipitation, peaking at 199 leaves in March 2005, and no living leaves were found after 103 days without rain. The environmental conditions prevalent at Centro Ecológico are very favorable for C. ciliaris, whose establishment was apparently triggered by a major disturbance caused by the development of housing projects.El Centro Ecológico de Sonora es un área natural protegida donde la vegetación autóctona permaneció sin disturbios por lo menos hasta 1997. Desde entonces, Cenchrus ciliaris se ha convertido en un elemento prominente de la vegetación. Se estudiaron el clima, las propiedades del suelo, la estructura de la población y la actividad biológica de C. ciliaris, como una aproximación al entendimiento de los mecanismos ecológicos que favorecieron la invasión por este pasto exótico. La temperatura media del aire y la precipitación anual fueron de 24.8 °C y 302 mm. El suelo fue una arena limosa pobre en minerales, pero particularmente rica en fósforo. Cenchrus ciliaris fue la especie herbácea más abundante en el Centro Ecológico, representando más de un tercio de la cobertura vegetal. El

  17. Keeping the Beat: A Large Sample Study of Bouncing and Clapping to Music.

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    Pauline Tranchant

    Full Text Available The vast majority of humans move in time with a musical beat. This behaviour has been mostly studied through finger-tapping synchronization. Here, we evaluate naturalistic synchronization responses to music-bouncing and clapping-in 100 university students. Their ability to match the period of their bounces and claps to those of a metronome and musical clips varying in beat saliency was assessed. In general, clapping was better synchronized with the beat than bouncing, suggesting that the choice of a specific movement type is an important factor to consider in the study of sensorimotor synchronization processes. Performance improved as a function of beat saliency, indicating that beat abstraction plays a significant role in synchronization. Fourteen percent of the population exhibited marked difficulties with matching the beat. Yet, at a group level, poor synchronizers showed similar sensitivity to movement type and beat saliency as normal synchronizers. These results suggest the presence of quantitative rather than qualitative variations when losing the beat.

  18. Keeping the Beat: A Large Sample Study of Bouncing and Clapping to Music

    Science.gov (United States)

    Tranchant, Pauline; Vuvan, Dominique T.; Peretz, Isabelle

    2016-01-01

    The vast majority of humans move in time with a musical beat. This behaviour has been mostly studied through finger-tapping synchronization. Here, we evaluate naturalistic synchronization responses to music–bouncing and clapping–in 100 university students. Their ability to match the period of their bounces and claps to those of a metronome and musical clips varying in beat saliency was assessed. In general, clapping was better synchronized with the beat than bouncing, suggesting that the choice of a specific movement type is an important factor to consider in the study of sensorimotor synchronization processes. Performance improved as a function of beat saliency, indicating that beat abstraction plays a significant role in synchronization. Fourteen percent of the population exhibited marked difficulties with matching the beat. Yet, at a group level, poor synchronizers showed similar sensitivity to movement type and beat saliency as normal synchronizers. These results suggest the presence of quantitative rather than qualitative variations when losing the beat. PMID:27471854

  19. The Short Supply of Saints: Limits on Replication of Models that "Beat the Odds"

    Science.gov (United States)

    Wilder, Tamara; Jacobsen, Rebecca

    2010-01-01

    Researchers have identified effective practices that allow schools to "beat the odds" and close the reading achievement gap. Although identifying these practices is important, researchers have paid little attention to the work it takes to implement them. Through interviews with teachers who work at schools identified as beating the odds, this…

  20. Midbrain adaptation may set the stage for the perception of musical beat.

    Science.gov (United States)

    Rajendran, Vani G; Harper, Nicol S; Garcia-Lazaro, Jose A; Lesica, Nicholas A; Schnupp, Jan W H

    2017-11-15

    The ability to spontaneously feel a beat in music is a phenomenon widely believed to be unique to humans. Though beat perception involves the coordinated engagement of sensory, motor and cognitive processes in humans, the contribution of low-level auditory processing to the activation of these networks in a beat-specific manner is poorly understood. Here, we present evidence from a rodent model that midbrain preprocessing of sounds may already be shaping where the beat is ultimately felt. For the tested set of musical rhythms, on-beat sounds on average evoked higher firing rates than off-beat sounds, and this difference was a defining feature of the set of beat interpretations most commonly perceived by human listeners over others. Basic firing rate adaptation provided a sufficient explanation for these results. Our findings suggest that midbrain adaptation, by encoding the temporal context of sounds, creates points of neural emphasis that may influence the perceptual emergence of a beat. © 2017 The Authors.

  1. Beat processing is pre-attentive for metrically simple rhythms with clear accents: an ERP study.

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    Fleur L Bouwer

    Full Text Available The perception of a regular beat is fundamental to music processing. Here we examine whether the detection of a regular beat is pre-attentive for metrically simple, acoustically varying stimuli using the mismatch negativity (MMN, an ERP response elicited by violations of acoustic regularity irrespective of whether subjects are attending to the stimuli. Both musicians and non-musicians were presented with a varying rhythm with a clear accent structure in which occasionally a sound was omitted. We compared the MMN response to the omission of identical sounds in different metrical positions. Most importantly, we found that omissions in strong metrical positions, on the beat, elicited higher amplitude MMN responses than omissions in weak metrical positions, not on the beat. This suggests that the detection of a beat is pre-attentive when highly beat inducing stimuli are used. No effects of musical expertise were found. Our results suggest that for metrically simple rhythms with clear accents beat processing does not require attention or musical expertise. In addition, we discuss how the use of acoustically varying stimuli may influence ERP results when studying beat processing.

  2. Peak misdetection in heart-beat-based security : Characterization and tolerance

    NARCIS (Netherlands)

    Seepers, Robert M; Strydis, Christos; Peris-Lopez, Pedro; Sourdis, Ioannis; De Zeeuw, Chris I

    The Inter-Pulse-Interval (IPI) of heart beats has previously been suggested for security in mobile health (mHealth) applications. In IPI-based security, secure communication is facilitated through a security key derived from the time difference between heart beats. However, there currently exists no

  3. Beat-wave laser accelerators, further comment including note on the 'Surfatron' concept

    International Nuclear Information System (INIS)

    Lawson, J.D.

    1984-07-01

    The paper deals with the Rutherford Appleton Laboratory (RAL) study of the beat-wave particle accelerator, intended for high energy physics. Three factors; the build-up of beat-wave, the surfatron concept and the self-focusing effects are considered in the context of the RAL study. (U.K.)

  4. Beat-by-beat analysis of cardiac output and blood pressure responses to short-term barostimulation in different body positions

    Science.gov (United States)

    Hildebrandt, Wulf; Schütze, Harald; Stegemann, J.

    Rapid quantification of the human baro-reflex control of heart rate has been achieved on a beat-by-beat basis using a neck-chamber with quick ECG-triggered pressure changes. Referring to recent findings on heart rate and stroke volume, the present study uses this technique to compare cardiac output as well as blood pressure changes in supine and upright position to investigate feedback effects and to confirm postural reflex modifications not revealed by RR-interval changes. A suction profile starting at +40 mmHg and running 7 steps of pressure decrease down to -65 mmHg was examined in 0° and 90° tilting position while beat-by-beat recordings were done of heart rate, stroke volume (impedance-cardiography) and blood pressure (Finapres tm) (n=16). The percentual heart rate decrease failed to be significantly different between positions. A suction-induced stroke volume increase led to a cardiac output almost maintained when supine and significantly increased when upright. A decrease in all blood pressure values was found during suction, except for systolic values in upright position which increased. Conclusively, (a) it is confirmed that different inotropy accounts for the seen gravitational effect on the cardiac output not represented by heart rate; (b) identical suction levels in different positions lead to different stimuli at the carotid receptor. This interference has to be considered in microgravity studies by beat-by-beat measurement of cardiac output and blood pressure.

  5. Vernier effect-based multiplication of the Sagnac beating frequency in ring laser gyroscope sensors

    Science.gov (United States)

    Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2018-02-01

    A multiplication method of the Sagnac effect scale factor in ring laser gyroscopes is presented based on the Vernier effect of a dual-coupler passive ring resonator coupled to the active ring. The multiplication occurs when the two rings have comparable lengths or integer multiples and their scale factors have opposite signs. In this case, and when the rings have similar areas, the scale factor is multiplied by ratio of their length to their length difference. The scale factor of the presented configuration is derived analytically and the lock-in effect is analyzed. The principle is demonstrated using optical fiber rings and semiconductor optical amplifier as gain medium. A scale factor multiplication by about 175 is experimentally measured, demonstrating larger than two orders of magnitude enhancement in the Sagnac effect scale factor for the first time in literature, up to the authors' knowledge.

  6. Influences of rolling method on deformation force in cold roll-beating forming process

    Science.gov (United States)

    Su, Yongxiang; Cui, Fengkui; Liang, Xiaoming; Li, Yan

    2018-03-01

    In process, the research object, the gear rack was selected to study the influence law of rolling method on the deformation force. By the mean of the cold roll forming finite element simulation, the variation regularity of radial and tangential deformation was analysed under different rolling methods. The variation of deformation force of the complete forming racks and the single roll during the steady state under different rolling modes was analyzed. The results show: when upbeating and down beating, radial single point average force is similar, the tangential single point average force gap is bigger, the gap of tangential single point average force is relatively large. Add itionally, the tangential force at the time of direct beating is large, and the dire ction is opposite with down beating. With directly beating, deformation force loading fast and uninstall slow. Correspondingly, with down beating, deformat ion force loading slow and uninstall fast.

  7. Phylogenetic analysis of the Neks reveals early diversification of ciliary-cell cycle kinases.

    Directory of Open Access Journals (Sweden)

    Jeremy D K Parker

    2007-10-01

    Full Text Available NIMA-related kinases (Neks have been studied in diverse eukaryotes, including the fungus Aspergillus and the ciliate Tetrahymena. In the former, a single Nek plays an essential role in cell cycle regulation; in the latter, which has more than 30 Neks in its genome, multiple Neks regulate ciliary length. Mammalian genomes encode an intermediate number of Neks, several of which are reported to play roles in cell cycle regulation and/or localize to centrosomes. Previously, we reported that organisms with cilia typically have more Neks than organisms without cilia, but were unable to establish the evolutionary history of the gene family.We have performed a large-scale analysis of the Nek family using Bayesian techniques, including tests of alternate topologies. We find that the Nek family had already expanded in the last common ancestor of eukaryotes, a ciliated cell which likely expressed at least five Neks. We suggest that Neks played an important role in the common ancestor in regulating cilia, centrioles, and centrosomes with respect to mitotic entry, and that this role continues today in organisms with cilia. Organisms that lack cilia generally show a reduction in the number of Nek clades represented, sometimes associated with lineage specific expansion of a single clade, as has occurred in the plants.This is the first rigorous phylogenetic analysis of a kinase family across a broad array of phyla. Our findings provide a coherent framework for the study of Neks and their roles in coordinating cilia and cell cycle progression.

  8. The ciliary margin zone of the mammalian retina generates retinal ganglion cells

    Science.gov (United States)

    Marcucci, Florencia; Murcia-Belmonte, Veronica; Coca, Yaiza; Ferreiro-Galve, Susana; Wang, Qing; Kuwajima, Takaaki; Khalid, Sania; Ross, M. Elizabeth; Herrera, Eloisa; Mason, Carol

    2016-01-01

    Summary The retina of lower vertebrates grows continuously by integrating new neurons generated from progenitors in the ciliary margin zone (CMZ). Whether the mammalian CMZ provides the neural retina with retinal cells is controversial. Live-imaging of embryonic retina expressing eGFP in the CMZ shows that cells migrate laterally from the CMZ to the neural retina where differentiated retinal ganglion cells (RGCs) reside. As Cyclin D2, a cell-cycle regulator, is enriched in ventral CMZ, we analyzed Cyclin D2−/− mice to test whether the CMZ is a source of retinal cells. Neurogenesis is diminished in Cyclin D2 mutants, leading to a reduction of RGCs in the ventral retina. In line with these findings, in the albino retina, the decreased production of ipsilateral RGCs is correlated with fewer Cyclin D2+ cells. Together, these results implicate the mammalian CMZ as a neurogenic site that produces RGCs and whose proper generation depends on Cyclin D2 activity. PMID:28009286

  9. Up-regulation of Ciliary Neurotrophic Factor in Astrocytes by Aspirin

    Science.gov (United States)

    Modi, Khushbu K.; Sendtner, Michael; Pahan, Kalipada

    2013-01-01

    Ciliary neurotrophic factor (CNTF) is a promyelinating trophic factor, and the mechanisms by which CNTF expression could be increased in the brain are poorly understood. Acetylsalicylic acid (aspirin) is one of the most widely used analgesics. Interestingly, aspirin increased mRNA and protein expression of CNTF in primary mouse and human astrocytes in a dose- and time-dependent manner. Aspirin induced the activation of protein kinase A (PKA) but not protein kinase C (PKC). H-89, an inhibitor of PKA, abrogated aspirin-induced expression of CNTF. The activation of cAMP-response element-binding protein (CREB), but not NF-κB, by aspirin, the abrogation of aspirin-induced expression of CNTF by siRNA knockdown of CREB, the presence of a consensus cAMP-response element in the promoter of CNTF, and the recruitment of CREB and CREB-binding protein to the CNTF promoter by aspirin suggest that aspirin increases the expression of the Cntf gene via the activation of CREB. Furthermore, we demonstrate that aspirin-induced astroglial CNTF was also functionally active and that supernatants of aspirin-treated astrocytes of wild type, but not Cntf null, mice increased myelin-associated proteins in oligodendrocytes and protected oligodendrocytes from TNF-α insult. These results highlight a new and novel myelinogenic property of aspirin, which may be of benefit for multiple sclerosis and other demyelinating disorders. PMID:23653362

  10. Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling

    International Nuclear Information System (INIS)

    Das, Ani V.; Zhao Xing; James, Jackson; Kim, Min; Cowan, Kenneth H.; Ahmad, Iqbal

    2006-01-01

    The identification of neural stem cells with retinal potential in the ciliary epithelium (CE) of the adult mammals is of considerable interest because of their potential for replacing or rescuing degenerating retinal neurons in disease or injury. The evaluation of such a potential requires characterization of these cells with regard to their phenotypic properties, potential, and regulatory mechanisms. Here, we demonstrate that rat CE stem cells/progenitors in neurosphere culture display astrocytic nature in terms of expressing glial intermediate neurofilament protein, GFAP. The GFAP-expressing CE stem cells/progenitors form neurospheres in proliferating conditions and generate neurons when shifted to differentiating conditions. These cells express components of the canonical Wnt pathway and its activation promotes their proliferation. Furthermore, we demonstrate that the activation of the canonical Wnt pathway influences neuronal differentiation of CE stem cells/progenitors in a context dependent manner. Our observations suggest that CE stem cells/progenitors share phenotypic properties and regulatory mechanism(s) with neural stem cells elsewhere in the adult CNS

  11. Intraocular gene transfer of ciliary neurotrophic factor rescues photoreceptor degeneration in RCS rats.

    Science.gov (United States)

    Huang, Shun-Ping; Lin, Po-Kang; Liu, Jorn-Hon; Khor, Chin-Ni; Lee, Yih-Jing

    2004-01-01

    Ciliary neurotrophic factor (CNTF) is known as an important factor in the regulation of retinal cell growth. We used both recombinant CNTF and an adenovirus carrying the CNTF gene to regulate retinal photoreceptor expression in a retinal degenerative animal, Royal College of Surgeons (RCS) rats. Cells in the outer nuclear layer of the retinae from recombinant-CNTF-treated, adenoviral-CNTF-treated, saline-operated, and contralateral untreated preparations were examined for those exhibiting CNTF photoreceptor protective effects. Cell apoptosis in the outer nuclear layer of the retinae was also detected. It was found that CNTF had a potent effect on delaying the photoreceptor degeneration process in RCS rats. Furthermore, adenovirus CNTF gene transfer was proven to be better at rescuing photoreceptors than that when using recombinant CNTF, since adenoviral CNTF prolonged the photoreceptor protection effect. The function of the photoreceptors was also examined by taking electroretinograms of different animals. Adenoviral-CNTF-treated eyes showed better retinal function than did the contralateral control eyes. This study indicates that adenoviral CNTF effectively rescues degenerating photoreceptors in RCS rats. Copyright 2004 National Science Council, ROC and S. Karger AG, Basel

  12. Reduced anaerobic and aerobic performance in children with primary ciliary dyskinesia.

    Science.gov (United States)

    Simsek, Senem; Inal-Ince, Deniz; Cakmak, Aslihan; Emiralioglu, Nagehan; Calik-Kutukcu, Ebru; Saglam, Melda; Vardar-Yagli, Naciye; Ozcelik, Hayriye Ugur; Sonbahar-Ulu, Hazal; Bozdemir-Ozel, Cemile; Kiper, Nural; Arikan, Hulya

    2018-05-01

    Primary ciliary dyskinesia (PCD) restricts lifestyle and increases morbidity. The aim of the study was to investigate anaerobic and aerobic performance in children with PCD and their healthy counterparts. Thirty-one children with PCD and 29 age- and sex-matched healthy subjects were studied. Pulmonary function, hand grip strength (HGS), quadriceps strength (QMS), physical activity, anaerobic capacity (muscle power sprint test), and aerobic performance (modified shuttle walk test (MSWT)) were determined. Pulmonary function, HGS, QMS, mean anaerobic power (MAP), and MSWT distance in PCD were significantly lower than those of healthy subjects (p aerobic performance is impaired in PCD from the early stages. Age determines anaerobic performance. Gender is the determinant of aerobic performance. Whether skeletal muscle characteristics and sex-related changes in body composition affect anaerobic and aerobic capacity in PCD children warrants further study. What is Known: • Exercise performance is determined by anaerobic and aerobic power. • Few studies have shown that PCD patients have lower aerobic performance which is associated with impaired lung function. What is New: • The present research indicated that both anaerobic and aerobic exercise capacity determined using field testing is impaired in PCD from the early stages. • Anaerobic capacity was found to be independently associated with age in PCD. Higher aerobic performance is independently associated with male gender.

  13. Apparent X-linked primary ciliary dyskinesia associated with retinitis pigmentosa and a hearing loss.

    Science.gov (United States)

    Krawczyński, Maciej R; Dmeńska, Hanna; Witt, Michał

    2004-01-01

    Three brothers, one 10-year-old and a pair of 14-year-old dizygotic twins--expressed the classical, early-onset retinitis pigmentosa (RP) with typical ophthalmoscopic findings, night blindness, visual field constricted to 10 degrees and flat ERG response. All three brothers were also diagnosed with primary ciliary dyskinesia (PCD) and had recurrent respiratory infections, chronic sinusitis and bronchiectasis. In all of them, resection of the middle lobe of the right lung was performed. A similar clinical picture of coexisting RP and PCD was noted in the brother of the probands' mother. All probands displayed situs solitus. Consistent with the X-linked mode of RP inheritance, there were also three obligatory female carriers of the disorder in this family: the mother of the affected boys, her mother and a daughter of her brother. In all of them, retinitis pigmentosa "sine pigmento" was found with milder but clinically significant symptoms (mild night blindness, visual field constricted to 30 degrees, and scotopic and photopic ERG responses reduced to 30-60%). No extraocular symptoms were detected in any of the heterozygous female carriers. This family presents an example of two rare phenomena: X-linked dominant retinitis pigmentosa (with milder expression in females) and a rare combination of RP with recurrent respiratory infections due to PCD.

  14. STOCHASTIC SIMULATION FOR BUFFELGRASS (Cenchrus ciliaris L. PASTURES IN MARIN, N. L., MEXICO

    Directory of Open Access Journals (Sweden)

    José Romualdo Martínez-López

    2014-04-01

    Full Text Available A stochastic simulation model was constructed to determine the response of net primary production of buffelgrass (Cenchrus ciliaris L. and its dry matter intake by cattle, in Marín, NL, México. Buffelgrass is very important for extensive livestock industry in arid and semiarid areas of northeastern Mexico. To evaluate the behavior of the model by comparing the model results with those reported in the literature was the objective in this experiment. Model simulates the monthly production of dry matter of green grass, as well as its conversion to senescence and dry grass and eventually to mulch, depending on precipitation and temperature. Model also simulates consumption of green and dry grass for cattle. The stocking rate used in the model simulation was 2 hectares per animal unit. Annual production ranged from 4.5 to 10.2 t of dry matter per hectare with annual rainfall of 300 to 704 mm, respectively. Total annual intake required per animal unit was estimated at 3.6 ton. Simulated net primary production coincides with reports in the literature, so the model was evaluated successfully.

  15. The effects of the stem cell on ciliary regeneration of injured rabbit sinonasal epithelium.

    Science.gov (United States)

    Kavuzlu, Ali; Tatar, Emel Çadallı; Karagöz, Tuğba; Pınarlı, Ferda Alpaslan; Tatar, İlkan; Bayır, Ömer; Korkmaz, Mehmet Hakan

    2017-08-01

    Defects in mucosal healing after sinonasal surgery cause infection, scar formation causing obstruction, relapse of the disease within a shorter period and revision surgery. The present study aimed to create a functional ciliated epithelium using a stem cell and stem cell sheet of adipose tissue origin and to show such regeneration ultra-structurally on experimentally injured rabbit nasal epithelium. This was an experimental animal study and basic research. A total of 18 white New Zealand rabbits were divided into three groups. The medial wall of the maxillary sinus of the subjects was peeled off bilaterally. No additional procedure was applied to the subjects in Group 1. In Group 2, adipose tissue-derived mesenchymal stem cell was implanted on the wound edges of the subjects. In Group 3, a stem cell sheet of three layers was laid onto the defect area. All subjects were killed after 3 weeks. The presence of the stem cell stained with bromo-deoxyuridine was assessed with a light microscope, whereas cilia density, ciliated orientation and cilia structure were evaluated with a scanning electron microscope. Ciliary densities in Group 2 and Group 3 were statistically superior compared to the control group (p stem cell increased the healing of the injured maxillary sinus mucosa of the rabbits in terms of cilia presence, density and morphology regardless of the implementation technique. Level of evidence NA.

  16. Central retinal and posterior ciliary artery occlusion after particle embolization of the external carotid artery system.

    Science.gov (United States)

    Mames, R N; Snady-McCoy, L; Guy, J

    1991-04-01

    A 15-year-old boy underwent neuroradiologic embolization of the left internal maxillary artery with polyvinyl alcohol to stop traumatic epistaxis after failure of surgical clipping and nasal packing. Selective catheterization of the external carotid artery before embolization showed a faint choroidal blush. Although the procedure provided hemostasis, embolization to the central retinal artery and ciliary arteries resulted in loss of vision. The route of the emboli to the eye was via the anastomotic network of the lacrimal artery supplied by the external carotid artery system. Neuroradiologic embolization of the external carotid artery is an effective mode of therapy for dural-cavernous fistulas when fed by the external carotid artery system. Because the blood flow to the brain and eye is predominantly supplied by the internal carotid artery, embolization of the external carotid artery is considered relatively safe. The authors document the importance of recognition of the choroidal blush during selective external carotid artery angiography as a sign of collateral blood flow to the eye. Physicians and patients need to be aware of the risk of blindness as a complication of external carotid artery embolization when this sign is present.

  17. Ion channels and beating heart: the players and the music

    Directory of Open Access Journals (Sweden)

    Charles Antzelevitch

    2011-12-01

    Full Text Available Soft gentle music accompanies us throughout our lifetime; it is the music of our heart beating. Although at times it is questionable as to who serves as conductor of the orchestra, there is little doubt that our ion channels are the main players. Whenever one of them plays too loudly, too softly or simply off key, disharmony results, sometimes leading to total disruption of the rate and rhythm. Ion channels can disrupt the music of our heart by different mechanisms. Sometimes their function is correct, but their expression is altered by underlying cardiac diseases (i.e. heart failure; sometimes the defect is in their structure, because of an underlying genetic defect, and in this case a channelopathy is present.

  18. The quantum beat principles and applications of atomic clocks

    CERN Document Server

    Major, F

    2007-01-01

    This work attempts to convey a broad understanding of the physical principles underlying the workings of these quantum-based atomic clocks, with introductory chapters placing them in context with the early development of mechanical clocks and the introduction of electronic time-keeping as embodied in the quartz-controlled clocks. While the book makes no pretense at being a history of atomic clocks, it nevertheless takes a historical perspective in its treatment of the subject. Intended for nonspecialists with some knowledge of physics or engineering, The Quantum Beat covers a wide range of salient topics relevant to atomic clocks, treated in a broad intuitive manner with a minimum of mathematical formalism. Detailed descriptions are given of the design principles of the rubidium, cesium, hydrogen maser, and mercury ion standards; the revolutionary changes that the advent of the laser has made possible, such as laser cooling, optical pumping, the formation of "optical molasses," and the cesium "fountain" stand...

  19. MD 979: Beta-beating measurements on colliding beams

    CERN Document Server

    Goncalves Jorge, Patrik; Pieloni, Tatiana; Buffat, Xavier; Carlier, Felix Simon; Coello De Portugal - Martinez Vazquez, Jaime Maria; Fol, Elena; Langner, Andy Sven; Medina Medrano, Luis Eduardo; Olexa, Jakub; Tomas Garcia, Rogelio; Valuch, Daniel; Wegscheider, Andreas; CERN. Geneva. ATS Department

    2017-01-01

    The HL-LHC high brightness beams will give a large β-beating due to the head-on and long-range interactions since a beam-beam parameter of 0.01 per Interaction Point (IP) is expected. The β-heating induced by two head-on collision reaches 15%. A third IP, i.e. IP8, could bring the β-heating up to 24%. The aim of the Machine Development (MD) study was to test optics measurements with AC dipole and ADT on colliding beams at injection and to implement a correction of the β-heating due to to head-on collision in the two experiments IP1&5. Int his note, we summarize the first results of this test performed in the LHC.

  20. Proceedings of the Annual Symposium on Frequency Control (44th) Held in Baltimore, Maryland on 23-25 May 1990

    Science.gov (United States)

    1990-01-01

    because the mean free path of the cesium atoms in the Cs Beam I :cesium beam tube must be much longer than the beam tube length. Consequently, aluminium ...mounting c-modes are measured vs. a thermometric beat frequency clips to the quartz plate. His "calculated results showed that is derived from the two c...return, thermometric beat frequency 3 in both Hertz and ppm. The bottom scale is the temperature limits. Experimental Configuration The repeatability of

  1. Increased Short-Term Beat-to-Beat QT Interval Variability in Patients with Impaired Glucose Tolerance

    Directory of Open Access Journals (Sweden)

    Andrea Orosz

    2017-06-01

    Full Text Available Prediabetic states and diabetes are important risk factors for cardiovascular morbidity and mortality. Determination of short-term QT interval variability (STVQT is a non-invasive method for assessment of proarrhythmic risk. The aim of the study was to evaluate the STVQT in patients with impaired glucose tolerance (IGT. 18 IGT patients [age: 63 ± 11 years, body mass index (BMI: 31 ± 6 kg/m2, fasting glucose: 6.0 ± 0.4 mmol/l, 120 min postload glucose: 9.0 ± 1.0 mmol/l, hemoglobin A1c (HbA1c: 5.9 ± 0.4%; mean ± SD] and 18 healthy controls (age: 56 ± 9 years, BMI: 27 ± 5 kg/m2, fasting glucose: 5.2 ± 0.4 mmol/l, 120 min postload glucose: 5.5 ± 1.3 mmol/l, HbA1c: 5.4 ± 0.3% were enrolled into the study. ECGs were recorded, processed, and analyzed off-line. The RR and QT intervals were expressed as the average of 30 consecutive beats, the temporal instability of beat-to-beat repolarization was characterized by calculating STVQT as follows: STVQT = Σ|QTn + 1 − QTn| (30x√2−1. Autonomic function was assessed by means of standard cardiovascular reflex tests. There were no differences between IGT and control groups in QT (411 ± 43 vs 402 ± 39 ms and QTc (431 ± 25 vs 424 ± 19 ms intervals or QT dispersion (44 ± 13 vs 42 ± 17 ms. However, STVQT was significantly higher in IGT patients (5.0 ± 0.7 vs 3.7 ± 0.7, P < 0.0001. The elevated temporal STVQT in patients with IGT may be an early indicator of increased instability of cardiac repolarization during prediabetic conditions.

  2. Dual-etalon cavity ring-down frequency-comb spectroscopy with broad band light source

    Science.gov (United States)

    Chandler, David W; Strecker, Kevin E

    2014-04-01

    In an embodiment, a dual-etalon cavity-ring-down frequency-comb spectrometer system is described. A broad band light source is split into two beams. One beam travels through a first etalon and a sample under test, while the other beam travels through a second etalon, and the two beams are recombined onto a single detector. If the free spectral ranges ("FSR") of the two etalons are not identical, the interference pattern at the detector will consist of a series of beat frequencies. By monitoring these beat frequencies, optical frequencies where light is absorbed may be determined.

  3. Disentangling beat perception from sequential learning and examining the influence of attention and musical abilities on ERP responses to rhythm.

    Science.gov (United States)

    Bouwer, Fleur L; Werner, Carola M; Knetemann, Myrthe; Honing, Henkjan

    2016-05-01

    Beat perception is the ability to perceive temporal regularity in musical rhythm. When a beat is perceived, predictions about upcoming events can be generated. These predictions can influence processing of subsequent rhythmic events. However, statistical learning of the order of sounds in a sequence can also affect processing of rhythmic events and must be differentiated from beat perception. In the current study, using EEG, we examined the effects of attention and musical abilities on beat perception. To ensure we measured beat perception and not absolute perception of temporal intervals, we used alternating loud and soft tones to create a rhythm with two hierarchical metrical levels. To control for sequential learning of the order of the different sounds, we used temporally regular (isochronous) and jittered rhythmic sequences. The order of sounds was identical in both conditions, but only the regular condition allowed for the perception of a beat. Unexpected intensity decrements were introduced on the beat and offbeat. In the regular condition, both beat perception and sequential learning were expected to enhance detection of these deviants on the beat. In the jittered condition, only sequential learning was expected to affect processing of the deviants. ERP responses to deviants were larger on the beat than offbeat in both conditions. Importantly, this difference was larger in the regular condition than in the jittered condition, suggesting that beat perception influenced responses to rhythmic events in addition to sequential learning. The influence of beat perception was present both with and without attention directed at the rhythm. Moreover, beat perception as measured with ERPs correlated with musical abilities, but only when attention was directed at the stimuli. Our study shows that beat perception is possible when attention is not directed at a rhythm. In addition, our results suggest that attention may mediate the influence of musical abilities on beat

  4. Proteomic analysis of isolated chlamydomonas centrioles reveals orthologs of ciliary-disease genes.

    Science.gov (United States)

    Keller, Lani C; Romijn, Edwin P; Zamora, Ivan; Yates, John R; Marshall, Wallace F

    2005-06-21

    The centriole is one of the most enigmatic organelles in the cell. Centrioles are cylindrical, microtubule-based barrels found in the core of the centrosome. Centrioles also act as basal bodies during interphase to nucleate the assembly of cilia and flagella. There are currently only a handful of known centriole proteins. We used mass-spectrometry-based MudPIT (multidimensional protein identification technology) to identify the protein composition of basal bodies (centrioles) isolated from the green alga Chlamydomonas reinhardtii. This analysis detected the majority of known centriole proteins, including centrin, epsilon tubulin, and the cartwheel protein BLD10p. By combining proteomic data with information about gene expression and comparative genomics, we identified 45 cross-validated centriole candidate proteins in two classes. Members of the first class of proteins (BUG1-BUG27) are encoded by genes whose expression correlates with flagellar assembly and which therefore may play a role in ciliogenesis-related functions of basal bodies. Members of the second class (POC1-POC18) are implicated by comparative-genomics and -proteomics studies to be conserved components of the centriole. We confirmed centriolar localization for the human homologs of four candidate proteins. Three of the cross-validated centriole candidate proteins are encoded by orthologs of genes (OFD1, NPHP-4, and PACRG) implicated in mammalian ciliary function and disease, suggesting that oral-facial-digital syndrome and nephronophthisis may involve a dysfunction of centrioles and/or basal bodies. By analyzing isolated Chlamydomonas basal bodies, we have been able to obtain the first reported proteomic analysis of the centriole.

  5. Evaluation of pulmonary disease using static lung volumes in primary ciliary dyskinesia.

    Science.gov (United States)

    Pifferi, Massimo; Bush, Andrew; Pioggia, Giovanni; Caramella, Davide; Tartarisco, Gennaro; Di Cicco, Maria; Zangani, Marta; Chinellato, Iolanda; Maggi, Fabrizio; Tezza, Giovanna; Macchia, Pierantonio; Boner, Attilio

    2012-11-01

    In primary ciliary dyskinesia (PCD) lung damage is usually evaluated by high-resolution CT (HRCT). To evaluate whether HRCT abnormalities and Pseudomonas aeruginosa infection were better predicted by spirometry or plethysmography. A cross-sectional study performed in consecutive patients with PCD who underwent sputum culture, spirometry, plethysmography and HRCT within 48 h. Principal component analysis and soft computing were used for data evaluation. Fifty patients (26 children) were studied. P aeruginosa infection was found in 40% of the patients and bronchiectasis in 88%. There was a correlation between infection with P aeruginosa and extent of bronchiectasis (p=0.009; r =0.367) and air-trapping (p=0.03; r =0.315). Moreover, there was an association between infection with P aeruginosa and residual volume (RV) values >150% (p=0.04) and RV/total lung capacity (TLC) ratio >140% (p=0.001), but not between infection with P aeruginosa and forced expiratory volume in 1 s (FEV(1))<80%, or forced expiratory flow between 25% and 75% of forced vital capacity (FVC) (FEF(25-75%))<70% or FEV(1)/FVC<70% (<80% in children). Severity of the total lung impairment on chest HRCT directly correlated with RV when expressed as per cent predicted (p=0.003; r =0.423), and RV/TLC (p<0.001; r =0.513) or when expressed as z scores (p=0.002, r =0.451 and p<0.001, r =0.536 respectively). Principal component analysis on plethysmographic but not on spirometry data allowed recognition of different severities of focal air trapping, atelectasis and extent of bronchiectasis. Plethysmography better predicts HRCT abnormalities than spirometry. Whether it might be a useful test to define populations of patients with PCD who should or should not have HRCT scans requires further longitudinal studies.

  6. Clinical outcomes of Ahmed glaucoma valve in anterior chamber versus ciliary sulcus.

    Science.gov (United States)

    Bayer, A; Önol, M

    2017-04-01

    PurposeTo evaluate the outcomes of Ahmed glaucoma valve (AGV) tube insertion through the anterior chamber angle (ACA) or through the ciliary sulcus (CS).Patients and methodsIn this case-control study, we retrospectively reviewed the charts of consecutive glaucoma patients who had undergone AGV implantation either through the ACA or the CS between March 2009 and December 2014. The main outcome measures were intraocular pressure (IOP), number of glaucoma medications prescribed, best corrected visual acuity (BCVA), glaucoma type, success rate, complications, and survival ratios. Statistical analysis was carried out using SPSS.ResultsThere were 68 eyes in the ACA group and 35 eyes in the CS group. There were no significant differences between the groups for age, sex, laterality, IOP, preoperative glaucoma medication number, BCVA or glaucoma type (P>0.05). The postoperative follow-up period was 27.2±16.5 months and 30.2±17.7 months for the ACA and the CS groups (P=0.28); IOP values were significantly reduced at the last visit to 16.4±7.2 mm Hg and 14.4±6.8 mm Hg. The difference in the last-visit IOP between the groups was not significant (P=0.06), but the IOP reduction ratio was higher in the CS group (P=0.03). There was no significant difference in the number of postoperative medications (P=0.18). Postoperative complications were similar, but the incidence of flat anterior chamber was higher in the ACA group (P=0.05).ConclusionsThe use of an AGV can control IOP in the majority of cases whether placed in the ACA or the CS. The IOP reduction ratio seemed to be higher in the CS group.

  7. In vitro assessment of TAT — Ciliary Neurotrophic Factor therapeutic potential for peripheral nerve regeneration

    International Nuclear Information System (INIS)

    Barbon, Silvia; Stocco, Elena; Negro, Alessandro; Dalzoppo, Daniele; Borgio, Luca; Rajendran, Senthilkumar; Grandi, Francesca; Porzionato, Andrea; Macchi, Veronica; De Caro, Raffaele

    2016-01-01

    In regenerative neurobiology, Ciliary Neurotrophic Factor (CNTF) is raising high interest as a multifunctional neurocytokine, playing a key role in the regeneration of injured peripheral nerves. Despite its promising trophic and regulatory activity, its clinical application is limited by the onset of severe side effects, due to the lack of efficient intracellular trafficking after administration. In this study, recombinant CNTF linked to the transactivator transduction domain (TAT) was investigated in vitro and found to be an optimized fusion protein which preserves neurotrophic activity, besides enhancing cellular uptake for therapeutic advantage. Moreover, a compelling protein delivery method was defined, in the future perspective of improving nerve regeneration strategies. Following determination of TAT-CNTF molecular weight and concentration, its specific effect on neural SH-SY5Y and PC12 cultures was assessed. Cell proliferation assay demonstrated that the fusion protein triggers PC12 cell growth within 6 h of stimulation. At the same time, the activation of signal transduction pathway and enhancement of cellular trafficking were found to be accomplished in both neural cell lines after specific treatment with TAT-CNTF. Finally, the recombinant growth factor was successfully loaded on oxidized polyvinyl alcohol (PVA) scaffolds, and more efficiently released when polymer oxidation rate increased. Taken together, our results highlight that the TAT domain addiction to the protein sequence preserves CNTF specific neurotrophic activity in vitro, besides improving cellular uptake. Moreover, oxidized PVA could represent an ideal biomaterial for the development of nerve conduits loaded with the fusion protein to be delivered to the site of nerve injury. - Highlights: • TAT-CNTF is an optimized fusion protein that preserves neurotrophic activity. • In neural cell lines, TAT-CNTF triggers the activation of signal transduction. • Fast cellular uptake of TAT-CNTF was

  8. In vitro assessment of TAT — Ciliary Neurotrophic Factor therapeutic potential for peripheral nerve regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Barbon, Silvia, E-mail: silvia.barbon@yahoo.it [Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131 Padua (Italy); Foundation for Biology and Regenerative Medicine, Tissue Engineering and Signaling (TES) ONLUS, Via De Sanctis 10, Caselle di Selvazzano Dentro, 35030 Padua (Italy); Stocco, Elena, E-mail: elena.stocco@gmail.com [Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131 Padua (Italy); Foundation for Biology and Regenerative Medicine, Tissue Engineering and Signaling (TES) ONLUS, Via De Sanctis 10, Caselle di Selvazzano Dentro, 35030 Padua (Italy); Negro, Alessandro, E-mail: alessandro.negro@unipd.it [Department of Biomedical Sciences, University of Padova, Via Colombo 3, 35121 Padua (Italy); Dalzoppo, Daniele, E-mail: daniele.dalzoppo@unipd.it [Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131 Padua (Italy); Borgio, Luca, E-mail: borgio.luca@gmail.com [Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131 Padua (Italy); Rajendran, Senthilkumar, E-mail: senthilstem@gmail.com [Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131 Padua (Italy); Grandi, Francesca, E-mail: francesca.grandi7825@gmail.com [Department of Women' s and Children' s Health, Pediatric Surgery, University of Padua, Via Giustiniani 3, 35121 Padua (Italy); Porzionato, Andrea, E-mail: andrea.porzionato@unipd.it [Section of Human Anatomy, Department of Molecular Medicine, University of Padua, Via Gabelli 65, 35121 Padua (Italy); Macchi, Veronica, E-mail: veronica.macchi@unipd.it [Section of Human Anatomy, Department of Molecular Medicine, University of Padua, Via Gabelli 65, 35121 Padua (Italy); De Caro, Raffaele, E-mail: raffaele.decaro@unipd.it [Section of Human Anatomy, Department of Molecular Medicine, University of Padua, Via Gabelli 65, 35121 Padua (Italy); and others

    2016-10-15

    In regenerative neurobiology, Ciliary Neurotrophic Factor (CNTF) is raising high interest as a multifunctional neurocytokine, playing a key role in the regeneration of injured peripheral nerves. Despite its promising trophic and regulatory activity, its clinical application is limited by the onset of severe side effects, due to the lack of efficient intracellular trafficking after administration. In this study, recombinant CNTF linked to the transactivator transduction domain (TAT) was investigated in vitro and found to be an optimized fusion protein which preserves neurotrophic activity, besides enhancing cellular uptake for therapeutic advantage. Moreover, a compelling protein delivery method was defined, in the future perspective of improving nerve regeneration strategies. Following determination of TAT-CNTF molecular weight and concentration, its specific effect on neural SH-SY5Y and PC12 cultures was assessed. Cell proliferation assay demonstrated that the fusion protein triggers PC12 cell growth within 6 h of stimulation. At the same time, the activation of signal transduction pathway and enhancement of cellular trafficking were found to be accomplished in both neural cell lines after specific treatment with TAT-CNTF. Finally, the recombinant growth factor was successfully loaded on oxidized polyvinyl alcohol (PVA) scaffolds, and more efficiently released when polymer oxidation rate increased. Taken together, our results highlight that the TAT domain addiction to the protein sequence preserves CNTF specific neurotrophic activity in vitro, besides improving cellular uptake. Moreover, oxidized PVA could represent an ideal biomaterial for the development of nerve conduits loaded with the fusion protein to be delivered to the site of nerve injury. - Highlights: • TAT-CNTF is an optimized fusion protein that preserves neurotrophic activity. • In neural cell lines, TAT-CNTF triggers the activation of signal transduction. • Fast cellular uptake of TAT-CNTF was

  9. Gene expression and functional annotation of the human ciliary body epithelia.

    Directory of Open Access Journals (Sweden)

    Sarah F Janssen

    Full Text Available PURPOSE: The ciliary body (CB of the human eye consists of the non-pigmented (NPE and pigmented (PE neuro-epithelia. We investigated the gene expression of NPE and PE, to shed light on the molecular mechanisms underlying the most important functions of the CB. We also developed molecular signatures for the NPE and PE and studied possible new clues for glaucoma. METHODS: We isolated NPE and PE cells from seven healthy human donor eyes using laser dissection microscopy. Next, we performed RNA isolation, amplification, labeling and hybridization against 44×k Agilent microarrays. For microarray conformations, we used a literature study, RT-PCRs, and immunohistochemical stainings. We analyzed the gene expression data with R and with the knowledge database Ingenuity. RESULTS: The gene expression profiles and functional annotations of the NPE and PE were highly similar. We found that the most important functionalities of the NPE and PE were related to developmental processes, neural nature of the tissue, endocrine and metabolic signaling, and immunological functions. In total 1576 genes differed statistically significantly between NPE and PE. From these genes, at least 3 were cell-specific for the NPE and 143 for the PE. Finally, we observed high expression in the (NPE of 35 genes previously implicated in molecular mechanisms related to glaucoma. CONCLUSION: Our gene expression analysis suggested that the NPE and PE of the CB were quite similar. Nonetheless, cell-type specific differences were found. The molecular machineries of the human NPE and PE are involved in a range of neuro-endocrinological, developmental and immunological functions, and perhaps glaucoma.

  10. Imaging of the 3D dynamics of flagellar beating in human sperm.

    Science.gov (United States)

    Silva-Villalobos, F; Pimentel, J A; Darszon, A; Corkidi, G

    2014-01-01

    The study of the mechanical and environmental factors that regulate a fundamental event such as fertilization have been subject of multiple studies. Nevertheless, the microscopical size of the spermatozoa and the high beating frequency of their flagella (up to 20 Hz) impose a series of technological challenges for the study of the mechanical factors implicated. Traditionally, due to the inherent characteristics of the rapid sperm movement, and to the technological limitations of microscopes (optical or confocal) to follow in three dimensions (3D) their movement, the analysis of their dynamics has been studied in two dimensions, when the head is confined to a surface. Flagella propel sperm and while their head can be confined to a surface, flagellar movement is not restricted to 2D, always displaying 3D components. In this work, we present a highly novel and useful tool to analyze sperm flagella dynamics in 3D. The basis of the method is a 100 Hz oscillating objective mounted on a bright field optical microscope covering a 16 microns depth space at a rate of ~ 5000 images per second. The best flagellum focused subregions were associated to their respective Z real 3D position. Unprecedented graphical results making evident the 3D movement of the flagella are shown in this work and supplemental material illustrating a 3D animation using the obtained experimental results is also included.

  11. Activating and relaxing music entrains the speed of beat synchronized walking

    OpenAIRE

    Leman, Marc; Moelants, Dirk; Varewyck, Matthias; Styns, Frederik; van Noorden, Leon; Martens, Jean-Pierre

    2013-01-01

    Inspired by a theory of embodied music cognition, we investigate whether music can entrain the speed of beat synchronized walking. If human walking is in synchrony with the beat and all musical stimuli have the same duration and the same tempo, then differences in walking speed can only be the result of music-induced differences in stride length, thus reflecting the vigor or physical strength of the movement. Participants walked in an open field in synchrony with the beat of 52 different musi...

  12. Quantum beat and entanglement of multi-qubits interacting with a common reservoir

    International Nuclear Information System (INIS)

    Sato, Arata; Ishi-Hayase, Junko; Minami, Fujio; Sasaki, Masahide

    2006-01-01

    The qubits can be entangled when they interact with a common Ohmic reservoir. We analyze how the reservoir-induced entanglement of qubits can be observed as the beat signal in the decay curve of the macroscopic polarization. The origin of this effect is the Lamb phase shift on the qubit array. We quantify the amount of the reservoir-induced entanglement and show how to experimentally evaluate it from the decay curve of the macroscopic polarization. We discuss how the beat signal can be discriminated from the other kinds of beat signals. We also show that our analysis can be used to estimate the reservoir characteristics

  13. Detection performance improvement of FMCW radar using frequency shift

    NARCIS (Netherlands)

    Wu, Y.; Linnartz, J.P.M.G.

    2011-01-01

    Frequency modulated continuous wave (FMCW) radars have been widely used for measuring target range and speed. In this paper, we present a mathematical model that quantifies the system-level performance of FMCW radar systems. In FMCW radar, the target range is measured through measuring the beat

  14. The role of hair cells, cilia and ciliary motility in otolith formation in the zebrafish otic vesicle.

    Science.gov (United States)

    Stooke-Vaughan, Georgina A; Huang, Peng; Hammond, Katherine L; Schier, Alexander F; Whitfield, Tanya T

    2012-05-01

    Otoliths are biomineralised structures required for the sensation of gravity, linear acceleration and sound in the zebrafish ear. Otolith precursor particles, initially distributed throughout the otic vesicle lumen, become tethered to the tips of hair cell kinocilia (tether cilia) at the otic vesicle poles, forming two otoliths. We have used high-speed video microscopy to investigate the role of cilia and ciliary motility in otolith formation. In wild-type ears, groups of motile cilia are present at the otic vesicle poles, surrounding the immotile tether cilia. A few motile cilia are also found on the medial wall, but most cilia (92-98%) in the otic vesicle are immotile. In mutants with defective cilia (iguana) or ciliary motility (lrrc50), otoliths are frequently ectopic, untethered or fused. Nevertheless, neither cilia nor ciliary motility are absolutely required for otolith tethering: a mutant that lacks cilia completely (MZovl) is still capable of tethering otoliths at the otic vesicle poles. In embryos with attenuated Notch signalling [mindbomb mutant or Su(H) morphant], supernumerary hair cells develop and otolith precursor particles bind to the tips of all kinocilia, or bind directly to the hair cells' apical surface if cilia are absent [MZovl injected with a Su(H)1+2 morpholino]. However, if the first hair cells are missing (atoh1b morphant), otolith formation is severely disrupted and delayed. Our data support a model in which hair cells produce an otolith precursor-binding factor, normally localised to tether cell kinocilia. We also show that embryonic movement plays a minor role in the formation of normal otoliths.

  15. SURGICAL INTERVENTION AND ACCOMMODATIVE RESPONSES: I. CENTRIPETAL CILIARY BODY, CAPSULE AND LENS MOVEMENT IN RHESUS MONKEYS OF VARYING AGE

    Science.gov (United States)

    Croft, Mary Ann; Mcdonald, Jared P.; James, Rebecca J.; Heatley, Gregg A.; Lin, Ting-Li; Lütjen-Drecoll, Elke; Kaufman, Paul L.

    2009-01-01

    Purpose To determine how surgically altering the normal relationship between the lens and the ciliary body in rhesus monkeys affects centripetal ciliary body and lens movement. Methods In 18 rhesus monkey eyes (aged 6–27 years), accommodation was induced before and after surgery by electrical stimulation of the Edinger-Westphal (E–W) nucleus. Accommodative amplitude was measured by coincidence refractometry. Goniovideography was performed before and after intra- and extra-capsular lens extraction (ICLE, ECLE) and anterior regional zonulolysis. Centripetal lens/capsule movements, centripetal ciliary process (CP) movements, and circumlental space were measured by computerized image analysis of the goniovideography images. Results Centripetal accommodative CP and capsule movement increased in velocity and amplitude post-ECLE compared to pre-ECLE regardless of age (n=5). The presence of the lens substance retarded capsule movement by ~21% in the young eyes and by ~62% in the older eyes. Post-ICLE compared to pre-ICLE centripetal accommodative CP movement was dampened in all eyes in which the anterior vitreous was disturbed (n=7), but not in eyes in which the anterior vitreous was left intact (n=2). Following anterior regional zonulolysis (n=4), lens position shifted toward the lysed quadrant during accommodation. Conclusions The presence of the lens substance, capsule zonular attachments, and Wiegers ligament may play a role in centripetal CP movement. The capsule is still capable of centripetal movement in the older eye (although at a reduced capacity) and may have the ability to produce ~6 diopters of accommodation in the presence of a normal young crystalline lens or a similar surrogate. PMID:18552393

  16. Readout for intersatellite laser interferometry: Measuring low frequency phase fluctuations of high-frequency signals with microradian precision

    DEFF Research Database (Denmark)

    Gerberding, Oliver; Diekmann, Christian; Kullmann, Joachim

    2015-01-01

    Precision phase readout of optical beat note signals is one of the core techniques required for inter-satellite laser interferometry. Future space based gravitational wave detectors like eLISA require such a readout over a wide range of MHz frequencies, due to orbit induced Doppler shifts...

  17. Beating-heart registration for organ-mounted robots.

    Science.gov (United States)

    Wood, Nathan A; Schwartzman, David; Passineau, Michael J; Moraca, Robert J; Zenati, Marco A; Riviere, Cameron N

    2018-03-06

    Organ-mounted robots address the problem of beating-heart surgery by adhering to the heart, passively providing a platform that approaches zero relative motion. Because of the quasi-periodic deformation of the heart due to heartbeat and respiration, registration must address not only spatial registration but also temporal registration. Motion data were collected in the porcine model in vivo (N = 6). Fourier series models of heart motion were developed. By comparing registrations generated using an iterative closest-point approach at different phases of respiration, the phase corresponding to minimum registration distance is identified. The spatiotemporal registration technique presented here reduces registration error by an average of 4.2 mm over the 6 trials, in comparison with a more simplistic static registration that merely averages out the physiological motion. An empirical metric for spatiotemporal registration of organ-mounted robots is defined and demonstrated using data from animal models in vivo. Copyright © 2018 John Wiley & Sons, Ltd.

  18. Electromyographic activity of beating and reaching during simulated boardsailing.

    Science.gov (United States)

    Buchanan, M; Cunningham, P; Dyson, R J; Hurrion, P D

    1996-04-01

    This study examined the responses of six competitive boardsailors (three males, three females) during laboratory-based simulation tasks while the electromyographic activity of up to 13 muscles was recorded. A sailboard, mounted in a steel frame and resting on a waterbed, allowed simulation of roll and pitch movements. Wind force was simulated by attaching the boom to a weight stack with a hydraulically controlled buffered release phase. The progression of the simulation test was controlled by the sailor copying movements on an edited video of each subject boardsailing on the open water. Analysis of individual pumping movements for mean peak percentage of maximal enveloped voluntary contraction (%MEVC) in 'beating' and 'reaching' showed that muscular activity in the arm (flexor carpi ulnaris, extensor carpi radialis and biceps brachii) was greatest (66-94% MEVC), with considerable activity (58-75% MEVC) in the deltoid and trapezius shoulder muscles, but much less activity in the leg muscles (16-40% MEVC). For the combined upper and lower body muscles there was a significant difference (P reflecting the current dynamic nature of the sport.

  19. Growth, biomass production and photosynthesis of Cenchrus ciliaris L. under Acacia tortilis (Forssk.) Hayne based silvopastoral systems in semi arid tropics.

    Science.gov (United States)

    Mishra, A K; Tiwari, H S; Bhatt, R K

    2010-11-01

    The growth, biomass production and photosynthesis of Cenchrus ciliaris was studied under the canopies of 17 yr old Acacia tortilis trees in semi arid tropical environment. On an average the full grown canopy of A. tortilis at the spacing of 4 x 4 m allowed 55% of total Photosynthetically Active Radiation (PAR) which in turn increased Relative Humidity (RH) and reduced under canopy temperature to -1.75 degrees C over the open air temperature. C. ciliaris attained higher height under the shade of A. tortilis. The tiller production and leaf area index decreased marginally under the shade of tree canopies as compared to the open grown grasses. C. ciliaris accumulated higher chlorophyll a and b under the shade of tree canopies indicating its shade adaptation potential. The assimilatory functions such as rate of photosynthesis, transpiration, stomatal conductance, photosynthetic water use efficiency (PN/TR) and carboxylation efficiency (PN/CINT) decreased under the tree canopies due to low availability of PAR. The total biomass production in term of fresh and dry weight decreased under the tree canopies. On average of 2 yr C. ciliaris had produced 12.78 t ha(-1) green and 3.72 -t ha(-1) dry biomass under the tree canopies of A. tortilis. The dry matter yield reduced to 38% under the tree canopies over the open grown grasses. The A. tortilis + C. ciliaris maintained higher soil moisture, organic carbon content and available N P K for sustainable biomass production for the longer period. The higher accumulation of crude protein, starch, sugar and nitrogen in leaves and stem of C. ciliaris indicates that this grass species also maintained its quality under A. tortilis based silvopastoral system. The photosynthesis and dry matter accumulation are closely associated with available PAR indicating that for sustainable production of this grass species in the silvopasture systems for longer period about 55% or more PAR is required.

  20. Application of a "relative" procedure to a problem in binaural beat perception.

    Science.gov (United States)

    1963-08-01

    The existence of binaural beats has long been considered an indication of binaural interaction for timing and for periodicity of information. In the past, bilaterally matched sound pressure or sensation levels have been used in the investigation of t...

  1. 3D force control for robotic-assisted beating heart surgery based on viscoelastic tissue model.

    Science.gov (United States)

    Liu, Chao; Moreira, Pedro; Zemiti, Nabil; Poignet, Philippe

    2011-01-01

    Current cardiac surgery faces the challenging problem of heart beating motion even with the help of mechanical stabilizer which makes delicate operation on the heart surface difficult. Motion compensation methods for robotic-assisted beating heart surgery have been proposed recently in literature, but research on force control for such kind of surgery has hardly been reported. Moreover, the viscoelasticity property of the interaction between organ tissue and robotic instrument further complicates the force control design which is much easier in other applications by assuming the interaction model to be elastic (industry, stiff object manipulation, etc.). In this work, we present a three-dimensional force control method for robotic-assisted beating heart surgery taking into consideration of the viscoelastic interaction property. Performance studies based on our D2M2 robot and 3D heart beating motion information obtained through Da Vinci™ system are provided.

  2. “Would you like to meet the secret Beat?” – Tram Combs and a Beat poetry less celebrated

    DEFF Research Database (Denmark)

    Sørensen, Bent

    of the poetry of Tram Combs, “the secret Beat”, whose 1957 collection Pilgrim’s Terrace contained forewords by both William Carlos Williams and Kenneth Rexroth, and whose collaborators included Allen Ginsberg – yet whose name is persistently left out of the Beat canon. One wonders why, when he is an example...... directly at Gorm, and asked: “Would you like to meet the secret Beat, then?” The old gentleman proceeded to introduce himself as Tram Combs, poet, bookseller, nude model and gay man about town, and for the next few days he took Gorm to art museums, gallery openings and story-telling sessions in his...

  3. A case report of primary ciliary dyskinesia, laterality defects and developmental delay caused by the co-existence of a single gene and chromosome disorder.

    LENUS (Irish Health Repository)

    Casey, Jillian P

    2015-01-01

    Primary ciliary dyskinesia (PCD) is a rare autosomal recessive disorder characterised by abnormal ciliary motion and impaired mucociliary clearance, leading to recurrent respiratory infections, sinusitis, otitis media and male infertility. Some patients also have laterality defects. We recently reported the identification of three disease-causing PCD genes in the Irish Traveller population; RSPH4A, DYX1C1 and CCNO. We have since assessed an additional Irish Traveller family with a complex phenotype involving PCD who did not have any of the previously identified PCD mutations.

  4. Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ning; ZHANG Hui-Min; LIU Zhi-Qiang; DING Xue-Li; YANG Ming-Hao; GU Hua-Guang; REN Wei

    2009-01-01

    Dissolved cardiac myocytes can couple together and generate synchronous beatings in culture. We observed a synchronized early after-depolarization(EAD)-like rhythm in cultured cardiac myocytes and reproduced the experimental observation in a network mathematical model whose dynamics are close to a Hopf bifurcation. The mechanism for this EAD-like rhythm is attributed to noised-induced stochastic alternatings between the focus and the limit cycle. These results provide novel understandings for pathological heart rhythms like the early immature beatings.

  5. Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins

    OpenAIRE

    Namdeo, S.; Onck, P. R.

    2016-01-01

    Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, ...

  6. The Effect of Iconic and Beat Gestures on Memory Recall in Greek's First and Second Language

    OpenAIRE

    Eleni Ioanna Levantinou

    2016-01-01

    Gestures play a major role in comprehension and memory recall due to the fact that aid the efficient channel of the meaning and support listeners’ comprehension and memory. In the present study, the assistance of two kinds of gestures (iconic and beat gestures) is tested in regards to memory and recall. The hypothesis investigated here is whether or not iconic and beat gestures provide assistance in memory and recall in Greek and in Greek speakers’ second language. Two gr...

  7. Pengaruh Brand Image (Citra Merek) Terhadapkeputusan Pembelian Sepeda Motor Honda Beat (Studipadamahasiswa/I Fisip Usu)

    OpenAIRE

    M, Hary Christian

    2017-01-01

    130907100 Penelitian ini bertujuan untuk mengetahui pengaruh Brand Image (Citra Merek) terhadap keputusan pembelian sepeda motor Honda Beat pada mahasiswa/i FISIP USU. Populasi dalam penelitian ini adalah mahasiwa/i FISIP USU yang memiliki dan menggunakan sepeda motor Honda Beat. Data dikumpulkan melalui melalui metode kuesioner terhadap 70 responden.Teknik pengambilan sampel dalam penelitian ini dilakukan dengan teknik Probability Sampling dengan pendekatan Simple Random Sampling.Jeni...

  8. Look at the Beat, Feel the Meter: Top-Down Effects of Meter Induction on Auditory and Visual Modalities.

    Science.gov (United States)

    Celma-Miralles, Alexandre; de Menezes, Robert F; Toro, Juan M

    2016-01-01

    Recent research has demonstrated top-down effects on meter induction in the auditory modality. However, little is known about these effects in the visual domain, especially without the involvement of motor acts such as tapping. In the present study, we aim to assess whether the projection of meter on auditory beats is also present in the visual domain. We asked 16 musicians to internally project binary (i.e., a strong-weak pattern) and ternary (i.e., a strong-weak-weak pattern) meter onto separate, but analog, visual and auditory isochronous stimuli. Participants were presented with sequences of tones or blinking circular shapes (i.e., flashes) at 2.4 Hz while their electrophysiological responses were recorded. A frequency analysis of the elicited steady-state evoked potentials allowed us to compare the frequencies of the beat (2.4 Hz), its first harmonic (4.8 Hz), the binary subharmonic (1.2 Hz), and the ternary subharmonic (0.8 Hz) within and across modalities. Taking the amplitude spectra into account, we observed an enhancement of the amplitude at 0.8 Hz in the ternary condition for both modalities, suggesting meter induction across modalities. There was an interaction between modality and voltage at 2.4 and 4.8 Hz. Looking at the power spectra, we also observed significant differences from zero in the auditory, but not in the visual, binary condition at 1.2 Hz. These findings suggest that meter processing is modulated by top-down mechanisms that interact with our perception of rhythmic events and that such modulation can also be found in the visual domain. The reported cross-modal effects of meter may shed light on the origins of our timing mechanisms, partially developed in primates and allowing humans to synchronize across modalities accurately.

  9. Look at the Beat, Feel the Meter: Top–Down Effects of Meter Induction on Auditory and Visual Modalities

    Science.gov (United States)

    Celma-Miralles, Alexandre; de Menezes, Robert F.; Toro, Juan M.

    2016-01-01

    Recent research has demonstrated top–down effects on meter induction in the auditory modality. However, little is known about these effects in the visual domain, especially without the involvement of motor acts such as tapping. In the present study, we aim to assess whether the projection of meter on auditory beats is also present in the visual domain. We asked 16 musicians to internally project binary (i.e., a strong-weak pattern) and ternary (i.e., a strong-weak-weak pattern) meter onto separate, but analog, visual and auditory isochronous stimuli. Participants were presented with sequences of tones or blinking circular shapes (i.e., flashes) at 2.4 Hz while their electrophysiological responses were recorded. A frequency analysis of the elicited steady-state evoked potentials allowed us to compare the frequencies of the beat (2.4 Hz), its first harmonic (4.8 Hz), the binary subharmonic (1.2 Hz), and the ternary subharmonic (0.8 Hz) within and across modalities. Taking the amplitude spectra into account, we observed an enhancement of the amplitude at 0.8 Hz in the ternary condition for both modalities, suggesting meter induction across modalities. There was an interaction between modality and voltage at 2.4 and 4.8 Hz. Looking at the power spectra, we also observed significant differences from zero in the auditory, but not in the visual, binary condition at 1.2 Hz. These findings suggest that meter processing is modulated by top–down mechanisms that interact with our perception of rhythmic events and that such modulation can also be found in the visual domain. The reported cross-modal effects of meter may shed light on the origins of our timing mechanisms, partially developed in primates and allowing humans to synchronize across modalities accurately. PMID:27047358

  10. Look at the Beat, Feel the Meter:Top-down Effects of Meter Induction on Auditory and Visual Modalities

    Directory of Open Access Journals (Sweden)

    Alexandre eCelma-Miralles

    2016-03-01

    Full Text Available Recent research has demonstrated top-down effects on meter induction in the auditory modality. However, little is known about these effects in the visual domain, especially without the involvement of motor acts such as tapping. In the present study, we aim to assess whether the projection of meter on auditory beats is also present in the visual domain. We asked sixteen musicians to internally project binary (i.e. a strong-weak pattern and ternary (i.e. a strong-weak-weak pattern meter onto separate, but analogue, visual and auditory isochronous stimuli. Participants were presented with sequences of tones or blinking circular shapes (i.e. flashes at 2.4 Hz while their electrophysiological responses were recorded. A frequency analysis of the elicited steady-state evoked potentials allowed us to compare the frequencies of the beat (2.4 Hz, its first harmonic (4.8 Hz, the binary subharmonic (1.2 Hz, and ternary subharmonic (0.8 Hz within and across modalities. Taking the amplitude spectra into account, we observed an enhancement of the amplitude at 0.8 Hz in the ternary condition for both modalities, suggesting meter induction across modalities. There was an interaction between modality and voltage at 2.4 and 4.8 Hz. Looking at the power spectra, we also observed significant differences from zero in the auditory, but not in the visual, binary condition at 1.2 Hz. These findings suggest that meter processing is modulated by top-down mechanisms that interact with our perception of rhythmic events and that such modulation can also be found in the visual domain. The reported cross-modal effects of meter may shed light on the origins of our timing mechanisms, partially developed in primates and allowing humans to synchronize across modalities accurately.

  11. Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins

    Science.gov (United States)

    Namdeo, S.; Onck, P. R.

    2016-10-01

    Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, their integration into a coherent picture of ATP-powered flagellar beating is still lacking. Here we show that a time-delayed negative-work-based switching mechanism is able to convert the individual sliding action of hundreds of dyneins into a regular overall beating pattern leading to propulsion. We developed a computational model based on a minimal representation of the axoneme consisting of two representative doublet microtubules connected by nexin links. The relative sliding of the microtubules is incorporated by modeling two groups of ATP-powered dyneins, each responsible for sliding in opposite directions. A time-delayed switching mechanism is postulated, which is key in converting the local individual sliding action of multiple dyneins into global beating. Our results demonstrate that an overall nonreciprocal beating pattern can emerge with time due to the spatial and temporal coordination of the individual dyneins. These findings provide insights in the fundamental working mechanism of axonemal dyneins and could possibly open new research directions in the field of flagellar motility.

  12. Effect of depth beating on the fiber properties and enzymatic saccharification efficiency of softwood kraft pulp.

    Science.gov (United States)

    Gao, Wenhua; Xiang, Zhouyang; Chen, Kefu; Yang, Rendang; Yang, Fei

    2015-01-01

    Commercial bleached softwood kraft pulp was mechanically fibrillated by a PFI-mill with beating revolution from 5000 to 30,000 r. The extent of fibrillating on the pulp was evaluated by beating degree, fiber morphological properties (fiber length, width, coarseness and curls index), water retention value (WRV) and physical properties of paper made from the pulp. Depth beating process significantly affected the pulp fibrillations as showed by the decreased fiber length and width as well as the SEM analysis, but the effects were limited after beating revolution of 15,000. Depth beating process also improved the total internal pore and inter-fibril surface areas as shown by the increased WRV values. Substrate enzymatic digestibility (SED) of beaten pulp at 5000 revolutions could reach 95% at cellulase loading of 15 FPU/g of glucan. After the enzymatic hydrolysis, the size of the pulp residues was reduced to micro-scale, and a relative uniform size distribution of the residues appeared at 10,000 r beating revolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Frequency-difference-dependent stochastic resonance in neural systems

    Science.gov (United States)

    Guo, Daqing; Perc, Matjaž; Zhang, Yangsong; Xu, Peng; Yao, Dezhong

    2017-08-01

    Biological neurons receive multiple noisy oscillatory signals, and their dynamical response to the superposition of these signals is of fundamental importance for information processing in the brain. Here we study the response of neural systems to the weak envelope modulation signal, which is superimposed by two periodic signals with different frequencies. We show that stochastic resonance occurs at the beat frequency in neural systems at the single-neuron as well as the population level. The performance of this frequency-difference-dependent stochastic resonance is influenced by both the beat frequency and the two forcing frequencies. Compared to a single neuron, a population of neurons is more efficient in detecting the information carried by the weak envelope modulation signal at the beat frequency. Furthermore, an appropriate fine-tuning of the excitation-inhibition balance can further optimize the response of a neural ensemble to the superimposed signal. Our results thus introduce and provide insights into the generation and modulation mechanism of the frequency-difference-dependent stochastic resonance in neural systems.

  14. Lung structure and function similarities between primary ciliary dyskinesia and mild cystic fibrosis: a pilot study.

    Science.gov (United States)

    Maglione, Marco; Montella, Silvia; Mollica, Carmine; Carnovale, Vincenzo; Iacotucci, Paola; De Gregorio, Fabiola; Tosco, Antonella; Cervasio, Mariarosaria; Raia, Valeria; Santamaria, Francesca

    2017-04-12

    Primary ciliary dyskinesia (PCD) and cystic fibrosis (CF) are increasingly compared. There are no chest magnetic resonance imaging (MRI) comparative studies of PCD and CF. We assessed clinical, functional, microbiological and MRI findings in PCD and mild CF patients in order to evaluate different expression of lung disease. Twenty PCD (15.1 years) and 20 CF subjects with mild respiratory impairment (16 years, 70% with pancreatic insufficiency) underwent MRI, spirometry, and sputum cultures when clinically stable. MRI was scored using the modified Helbich system. PCD was diagnosed later than CF (9.9 versus 0.6 years, p = 0.03), despite earlier symptoms (0.1 versus 0.6 years, p = 0.02). In the year preceding the study, patients from both groups underwent two systemic antibiotic courses (p = 0.48). MRI total scores were 11.6 ± 0.7 and 9.1 ± 1 in PCD and CF, respectively. FEV 1 and FVC Z-scores were -1.75 (range, -4.6-0.7) and -0.6 (-3.9-1.8) in PCD, and -0.9 (range, -5.4-2.3) and -0.3 (-3.4-2.5) in CF, respectively. No difference was found between lung function or structure, despite a higher MRI subscore of collapse/consolidation in PCD versus CF (1.6 ± 0.1 and 0.6 ± 0.2, p < 0.001). These findings were confirmed after data-control for diagnostic delay. Pseudomonas aeruginosa and Staphylococcus aureus were more frequent in CF than in PCD (p = 0.05 and p = 0.003, respectively). MRI is a valuable radiation-free tool for comparative PCD and CF lung disease assessment. Patients with PCD may exhibit similar MRI and lung function changes as CF subjects with mild pulmonary disease. Delay in PCD diagnosis is unlikely the only determinant of similarities.

  15. Does the disruption of horizontal anterior ciliary vessels affect the blood-aqueous barrier function?

    Science.gov (United States)

    Pan, Meihua; Yang, Mei; Xie, Renyi; Zhao, Zhimin; Huang, Xingxing

    2017-12-01

    To investigate the significance of the anterior ciliary vessels (ACVs) preservation during the conventional horizontal strabismus surgery. Patients (≥ 8 years) with horizontal strabismus were randomly allocated into group 1 (with ACV preservation) and group 2 (without ACV preservation). The surgical eyes in group 1 were further divided into group A (one rectus muscle operated) and group B (two rectus muscles operated). Similarly, eyes in group 2 were divided into group C (one rectus muscle operated) and group D (two rectus muscles operated). The success rate of ACV preservation was calculated. The anterior chamber flare measurements of each eye by laser flare photometry were recorded on the day prior to and after operation. The flare values between groups and between pre- and post-operation in each group were compared by one-way analysis of variance and a paired t-test respectively. In groups A and B, the success rate of ACV preservation was 82% (27/33) and 70% (28/40)respectively, and the flare values between pre- and post-operation showed no significant differences(4.378 ± 1.527, 4.544 ± 1.452, P = 0.526; 4.625 ± 1.090, 4.989 ± 1.468, P = 0.101 respectively). However, the postoperative values were significantly increased in group C and group D(4.661 ± 1.031, 5.039 ± 1.310, P = 0.025; 4.933 ± 1.691, 5.502 ± 1.430, P = 0.000 respectively). The postoperative flare readings of group D were significantly higher than group B, while group A and group C had no significant variation. ACV preservation probably has clinical significance in reducing the undesirable influence on the blood-aqueous barrier.

  16. [Endoscopically controlled optimization of trans-scleral suture fixation of posterior chamber lenses in the ciliary sulcus].

    Science.gov (United States)

    Althaus, C; Sundmacher, R

    1993-08-01

    Two technical difficulties have to be overcome in transscleral suture fixation of posterior chamber intraocular lenses (PCL) in the ciliary sulcus: first, exact needle penetration through the sulcus, and second, exact positioning of the PCL haptics in the sulcus. Incongruence of the two may lead to long-term complications by compression or even strangulation of ciliary processes. Intraocular endoscopy was used intraoperatively to visualize the site of needle penetration and the final location of the haptics in patients. It turned out that with our previously described standard techniques the precision was far less than anticipated. Thus, new technical ways had to be sought to improve the precision of positioning. In secondary implantation without perforating keratoplasty we achieved the best results when the needle was passed ab externo before opening the eye and before anterior vitrectomy, taking advantage of a precisely prepared sclerocorneal zone. Passing the needle ab externo in an already hypotonic eyeball gives much less precise results. In combination with perforating keratoplasty with an open-sky approach, needle penetration ab interno is reliable. Correct positioning of the PCL haptics is at least as difficult as correct needle penetration, a fact which up to now has mostly been ignored. In 33 consecutively operated eyes the technique of implantation and PCL design was varied under endoscopical control.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Control of ciliary motility by Ca2+: Integration of Ca2+-dependent functions and targets for Ca2+ action

    International Nuclear Information System (INIS)

    Evans, T.C.

    1988-01-01

    To identify functions that regulate Ca 2+ -induced ciliary reversal in Paramecium, mutants defective in terminating depolarization-induced backward swimming were selected. Six independent recessive mutations (k-shy) comprising two complementation groups, k-shyA and k-shyB, were identified. All mutants exhibited prolonged backward swimming in depolarizing solutions. Voltage clamp studies revealed that mutant Ca 2+ current amplitudes were reduced, but could be restored to wild type levels by EGTA injection. The recovery of the mutant Ca 2+ current from Ca 2+ -dependent inactivation, and the decay of the Ca 2+ -dependent K + and Ca 2+ -dependent Na + currents after depolarization were slow in k-shy compared to wild type. To identify protein targets of Ca 2+ action, ciliary proteins that interact with calmodulin (CaM) were characterized. With a 125 I-CaM blot assay, several CaM-binding proteins were identified including axonemal, soluble, and membrane-bound polypeptides. Competitive displacement studies with unlabeled Paramecium CaM, bovine CaM, and troponinC suggested that both protein types bind CaM with high affinity and specificity. To examine the presence of CaM-binding sites in intact axonemes, a filtration binding assay was developed

  18. Chloral hydrate alters the organization of the ciliary basal apparatus and cell organelles in sea urchin embryos

    Science.gov (United States)

    Chakrabarti, A.; Schatten, H.; Mitchell, K. D.; Crosser, M.; Taylor, M.

    1998-01-01

    The mitotic inhibitor, chloral hydrate, induces ciliary loss in the early embryo phase of Lytechinus pictus. It causes a breakdown of cilia at the junction of the cilium and the basal body known as the basal plate. This leaves the plasma membrane temporarily unsealed. The basal apparatus accessory structures, consisting of the basal body, basal foot, basal foot cap, striated side arm, and striated rootlet, are either misaligned or disintegrated by treatment with chloral hydrate. Furthermore, microtubules which are associated with the basal apparatus are disassembled. Mitochondria accumulate at the base of cilia - underneath the plasma membrane - and show alterations in their structural organization. The accumulation of mitochondria is observed in 40% of all electron micrograph sections while 60% show the areas mostly devoid of mitochondria. The microvilli surrounding a cilium and striated rootlet remain intact in the presence of chloral hydrate. These results suggest that deciliation in early sea urchin embryos by chloral hydrate is caused by combined effects on the ciliary membrane and on microtubules in the cilia. Furthermore, it is suggested that chloral hydrate can serve as a tool to explore the cytoskeletal mechanisms that are involved in cilia motility in the developing sea urchin embryo.

  19. Wife beating refusal among women of reproductive age in urban and rural Ethiopia.

    Science.gov (United States)

    Gurmu, Eshetu; Endale, Senait

    2017-03-16

    Wife beating is the most common and widespread form of intimate partner violence in Ethiopia. It results in countless severe health, socio-economic and psychological problems and has contributed to the violation of human rights including the liberty of women to enjoy conjugal life. The main purpose of this study is to assess the levels and patterns of wife beating refusal and its associated socio-cultural and demographic factors in rural and urban Ethiopia. The 2011 Ethiopian Demographic and Health Survey (EDHS) data based on 11,097 and 5287 women in the reproductive age group (i.e. 15-49 years) living in rural and urban areas, respectively,were used in this study. Cronbach's alpha was used to assess the internal consistency of the measure of women's attitudes towards wife beating. The Statistical Package for Social Sciences was applied to analyze the data. A binary logistic regression model was fitted to identify variables that significantly predict respondents' refusal of wife beating. Separate analysis by a place of residence was undertaken as attitude towards wife beating vary between rural and urban areas. The likelihood of refusing wife beating in Ethiopia was significantly higher among urban women (54.2%) than rural women (24.5%). Although there was a significant variations in attitude towards refusing wife beating among different regions in Ethiopia, increasing educational level, high access to media, age of respondents were associated with high level of refusal of wife beating. In contrast, rural residence, being in marital union, high number of living children, being followers of some religions (Muslim followers in urban and Protestants in rural) were associated with low level of refusal of wife beating. The findings of this study reveal that wife beating in Ethiopia is a function of demographic and socio-cultural factors among which age and educational attainment of respondents, number of living children, religious affiliation, marital commitment and

  20. To beat or not to beat a tick: comparison of DNA extraction methods for ticks (Ixodes scapularis

    Directory of Open Access Journals (Sweden)

    Alyssa D. Ammazzalorso

    2015-08-01

    Full Text Available Background. Blacklegged ticks (Ixodes scapularis are important disease vectors in the United States, known to transmit a variety of pathogens to humans, including bacteria, protozoa, and viruses. Their importance as a disease vector necessitates reliable and comparable methods for extracting microbial DNA from ticks. Furthermore, to explore the population genetics or genomics of this tick, appropriate DNA extraction techniques are needed for both the vector and its microbes. Although a few studies have investigated different methods of DNA isolation from ticks, they are limited in the number and types of DNA extraction and lack species-specific quantification of DNA yield.Methods. Here we determined the most efficient and consistent method of DNA extraction from two different developmental stages of I. scapularis—nymph and adult—that are the most important for disease transmission. We used various methods of physical disruption of the hard, chitinous exoskeleton, as well as commercial and non-commercial DNA isolation kits. To gauge the effectiveness of these methods, we quantified the DNA yield and confirmed the DNA quality via PCR of both tick and microbial genetic material.Results. DNA extraction using the Thermo GeneJET Genomic DNA Purification Kit resulted in the highest DNA yields and the most consistent PCR amplification when combined with either cutting or bead beating with select matrices across life stages. DNA isolation methods using ammonium hydroxide as well as the MoBio PowerSoil kit also produced strong and successful PCR amplification, but only for females.Discussion. We contrasted a variety of readily available methods of DNA extraction from single individual blacklegged ticks and presented the results through a quantitative and qualitative assessment.

  1. Cross-cultural influences on rhythm processing: reproduction, discrimination, and beat tapping.

    Science.gov (United States)

    Cameron, Daniel J; Bentley, Jocelyn; Grahn, Jessica A

    2015-01-01

    The structures of musical rhythm differ between cultures, despite the fact that the ability to entrain movement to musical rhythm occurs in virtually all individuals across cultures. To measure the influence of culture on rhythm processing, we tested East African and North American adults on perception, production, and beat tapping for rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were the same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced by the culture of the participant and the culture of the rhythm. Specifically, we predicted that a participant's ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than for unfamiliar rhythms. Moreover, there were differences between the two participant groups, and between the two types of rhythms, in the metrical level selected for beat tapping. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion.

  2. Extracting fetal heart beats from maternal abdominal recordings: selection of the optimal principal components

    International Nuclear Information System (INIS)

    Di Maria, Costanzo; Liu, Chengyu; Zheng, Dingchang; Murray, Alan; Langley, Philip

    2014-01-01

    This study presents a systematic comparison of different approaches to the automated selection of the principal components (PC) which optimise the detection of maternal and fetal heart beats from non-invasive maternal abdominal recordings. A public database of 75 4-channel non-invasive maternal abdominal recordings was used for training the algorithm. Four methods were developed and assessed to determine the optimal PC: (1) power spectral distribution, (2) root mean square, (3) sample entropy, and (4) QRS template. The sensitivity of the performance of the algorithm to large-amplitude noise removal (by wavelet de-noising) and maternal beat cancellation methods were also assessed. The accuracy of maternal and fetal beat detection was assessed against reference annotations and quantified using the detection accuracy score F1 [2*PPV*Se / (PPV + Se)], sensitivity (Se), and positive predictive value (PPV). The best performing implementation was assessed on a test dataset of 100 recordings and the agreement between the computed and the reference fetal heart rate (fHR) and fetal RR (fRR) time series quantified. The best performance for detecting maternal beats (F1 99.3%, Se 99.0%, PPV 99.7%) was obtained when using the QRS template method to select the optimal maternal PC and applying wavelet de-noising. The best performance for detecting fetal beats (F1 89.8%, Se 89.3%, PPV 90.5%) was obtained when the optimal fetal PC was selected using the sample entropy method and utilising a fixed-length time window for the cancellation of the maternal beats. The performance on the test dataset was 142.7 beats 2 /min 2 for fHR and 19.9 ms for fRR, ranking respectively 14 and 17 (out of 29) when compared to the other algorithms presented at the Physionet Challenge 2013. (paper)

  3. CCDC39 is required for assembly of inner dynein arms and the dynein regulatory complex and for normal ciliary motility in humans and dogs

    DEFF Research Database (Denmark)

    Merveille, Anne-Christine; Davis, Erica E; Becker-Heck, Anita

    2011-01-01

    Primary ciliary dyskinesia (PCD) is an inherited disorder characterized by recurrent infections of the upper and lower respiratory tract, reduced fertility in males and situs inversus in about 50% of affected individuals (Kartagener syndrome). It is caused by motility defects in the respiratory c...

  4. The eye-catching cicada Hamza ciliaris (Linnaeus, 1758) comb. n. in Indonesia and the Pacific: taxonomie status, synonymy, and distribution (Homoptera, Cicadoidea)

    NARCIS (Netherlands)

    Duffels, J.P.

    1991-01-01

    The new combination Hamza ciliaris (Linnaeus) is proposed for a cicada species widely distributed in Maluku ( = Moluccas), Timor, Banda, Kei and Banggai Islands, the Philippines, and the Palau group of the Caroline Islands. The synonymy of five species, treated in the literature as junior synonyms

  5. Soliton radiation beat analysis of optical pulses generated from two continuous-wave lasers

    Science.gov (United States)

    Zajnulina, M.; Böhm, M.; Blow, K.; Rieznik, A. A.; Giannone, D.; Haynes, R.; Roth, M. M.

    2015-10-01

    We propose a fibre-based approach for generation of optical frequency combs (OFCs) with the aim of calibration of astronomical spectrographs in the low and medium-resolution range. This approach includes two steps: in the first step, an appropriate state of optical pulses is generated and subsequently moulded in the second step delivering the desired OFC. More precisely, the first step is realised by injection of two continuous-wave (CW) lasers into a conventional single-mode fibre, whereas the second step generates a broad OFC by using the optical solitons generated in step one as initial condition. We investigate the conversion of a bichromatic input wave produced by two initial CW lasers into a train of optical solitons, which happens in the fibre used as step one. Especially, we are interested in the soliton content of the pulses created in this fibre. For that, we study different initial conditions (a single cosine-hump, an Akhmediev breather, and a deeply modulated bichromatic wave) by means of soliton radiation beat analysis and compare the results to draw conclusion about the soliton content of the state generated in the first step. In case of a deeply modulated bichromatic wave, we observed the formation of a collective soliton crystal for low input powers and the appearance of separated solitons for high input powers. An intermediate state showing the features of both, the soliton crystal and the separated solitons, turned out to be most suitable for the generation of OFC for the purpose of calibration of astronomical spectrographs.

  6. Ultrasound functional imaging in an ex vivo beating porcine heart platform

    Science.gov (United States)

    Petterson, Niels J.; Fixsen, Louis S.; Rutten, Marcel C. M.; Pijls, Nico H. J.; van de Vosse, Frans N.; Lopata, Richard G. P.

    2017-12-01

    In recent years, novel ultrasound functional imaging (UFI) techniques have been introduced to assess cardiac function by measuring, e.g. cardiac output (CO) and/or myocardial strain. Verification and reproducibility assessment in a realistic setting remain major issues. Simulations and phantoms are often unrealistic, whereas in vivo measurements often lack crucial hemodynamic parameters or ground truth data, or suffer from the large physiological and clinical variation between patients when attempting clinical validation. Controlled validation in certain pathologies is cumbersome and often requires the use of lab animals. In this study, an isolated beating pig heart setup was adapted and used for performance assessment of UFI techniques such as volume assessment and ultrasound strain imaging. The potential of performing verification and reproducibility studies was demonstrated. For proof-of-principle, validation of UFI in pathological hearts was examined. Ex vivo porcine hearts (n  =  6, slaughterhouse waste) were resuscitated and attached to a mock circulatory system. Radio frequency ultrasound data of the left ventricle were acquired in five short axis views and one long axis view. Based on these slices, the CO was measured, where verification was performed using flow sensor measurements in the aorta. Strain imaging was performed providing radial, circumferential and longitudinal strain to assess reproducibility and inter-subject variability under steady conditions. Finally, strains in healthy hearts were compared to a heart with an implanted left ventricular assist device, simulating a failing, supported heart. Good agreement between ultrasound and flow sensor based CO measurements was found. Strains were highly reproducible (intraclass correlation coefficients  >0.8). Differences were found due to biological variation and condition of the hearts. Strain magnitude and patterns in the assisted heart were available for different pump action, revealing

  7. Energy harvesting from the tail beating of a carangiform swimmer using ionic polymer–metal composites

    International Nuclear Information System (INIS)

    Cha, Youngsu; Verotti, Matteo; Walcott, Horace; Peterson, Sean D; Porfiri, Maurizio

    2013-01-01

    In this paper, we study energy harvesting from the beating of a biomimetic fish tail using ionic polymer–metal composites. The design of the biomimetic tail is based on carangiform swimmers and is specifically inspired by the morphology of the heterocercal tail of thresher sharks. The tail is constituted of a soft silicone matrix molded in the form of the heterocercal tail and reinforced by a steel beam of rectangular cross section. We propose a modeling framework for the underwater vibration of the biomimetic tail, wherein the tail is assimilated to a cantilever beam with rectangular cross section and heterogeneous physical properties. We focus on base excitation in the form of a superimposed rotation about a fixed axis and we consider the regime of moderately large-amplitude vibrations. In this context, the effect of the encompassing fluid is described through a hydrodynamic function, which accounts for inertial, viscous and convective phenomena. The model is validated through experiments in which the base excitation is systematically varied and the motion of selected points on the biomimetic tail tracked in time. The feasibility of harvesting energy from an ionic polymer–metal composite attached to the vibrating structure is experimentally and theoretically assessed. The response of the transducer is described using a black-box model, where the voltage output is controlled by the rate of change of the mean curvature. Experiments are performed to elucidate the impact of the shunting resistance, the frequency of the base excitation and the placement of the ionic polymer–metal composite on energy harvesting from the considered biomimetic tail. (paper)

  8. An empirical investigation of attitudes towards wife-beating among men and women in seven sub-Saharan African countries.

    Science.gov (United States)

    Rani, Manju; Bonu, Sekhar; Diop-Sidibe, Nafissatou

    2004-12-01

    This study used data from the demographic and health surveys (DHS) conducted between 1999 and 2001 in Benin, Ethiopia, Malawi, Mali, Rwanda, Uganda and Zimbabwe, to examine the magnitude and correlates of conditional acceptance of wife-beating among both men and women. Multivariate logistic regression models were fitted to investigate the independent association between different socio-demographic characteristics and acceptance of wife-beating. The acceptance of wife-beating for transgressing certain gender roles was widespread in all the countries. Men were consistently less likely to justify wife-beating than women. Household wealth and education emerged as strongest and most consistent negative predictors of acceptance of wife-beating among both men and women. Older men and women were less likely to justify wife-beating. Men and women in the polygamous union were more likely to accept wife-beating, though the association was not always significant. With the exception of Uganda, women working for pay were more likely to justify wife-beating than non-working women were. The results indicate that dominant social and cultural norms create images of "ideal" women among both men and women that include definition and widespread acceptance of gender roles as well as sanction use of force to enforce these gender roles. The State and its different institutions may fail to mitigate wife-beating, as sensitivity to objectively address wife-beating may be tellingly lacking. Though education, economic growth, etc, can reduce acceptance of wife-beating, the process may be too slow and too late to make a substantial difference in the near future. Proactive measures may be required to change attitudes towards wife-beating among both men and women.

  9. Discinesia ciliar primária: quando o pediatra deve suspeitar e como diagnosticar? Primary ciliary dyskinesia: when the pediatrician must suspect and how to do the diagnosis?

    Directory of Open Access Journals (Sweden)

    Mary Anne K. Olm

    2007-12-01

    from secondary ciliary defects and to describe the clinical features, screening and diagnostic laboratorial tests, and the clinical management of this disorder. DATA SOURCES: A bibliographical search was obtained from Medline, Lilacs and SciELO databases, from 1980 to 2007. DATA SYNTHESIS: PCD is an autossomic recessive disorder with abnormal structure and/or function of the cilia, leading to reduced mucociliary clearance. The clinical manifestations include upper and lower respiratory tracts, with recurrent ear, sinus and lung infections that may progress to bronchiectasis. Situs inversus and male infertility are other clinical features of this disorder. PCD should be suspected by pediatricians in the following clinical situations: full term neonates with respiratory distress without apparent causes, presence of dextrocardia, infants with chronic cough and/or recurrent upper airways infections in the absence of immunodeficiency and cystic fibrosis, children with atypical asthma and bronchiectasis without a definitive cause. The diagnostic screening tests are the saccharine and nasal nitric oxide tests. Functional and ultrastructural evaluations demand an electronic microscopic analysis and the observation of the frequency and the pattern of the ciliary movement. CONCLUSIONS: Although the prevalence of PCD is low, the difficulties in establishing the diagnosis due to the complex investigations demanded and the unfamiliarity of the disease by physicians lead to underdiagnosis. Early diagnosis and treatment of PCD are essential to reduce the morbidity and to avoid complications.

  10. The Beats as Cultural Others/Exotics in Recent Memoirs by Exile Poets

    DEFF Research Database (Denmark)

    Sørensen, Bent

    Poets who have come to the USA during the 1950s and 60s as expatriates or exiles from central European countries dominated by Communist regimes have often looked to Beat Generation writers as role models and inspirational figures. This is no doubt due to the spirit of individuality, non-conformis......Poets who have come to the USA during the 1950s and 60s as expatriates or exiles from central European countries dominated by Communist regimes have often looked to Beat Generation writers as role models and inspirational figures. This is no doubt due to the spirit of individuality, non......-conformism and jubilant celebration of difference and otherness which permeates the writings of poets such as Allen Ginsberg, and which resonated with dissident poets often oppressed by totalitarian regimes. Authors such as Andrei Codrescu and Charles Simic have published memoirs and poems detailing their fascination...... with figures associated with the Beat Generation. This paper examines the representation of Beat writers such as Ginsberg and Jack Kerouac in Codrescu and Simic's texts, and argues that the exile poets overlay the well-known figures of the Beat writers with yet another dimension of otherness and exoticism...

  11. Beating of Aharonov-Bohm oscillations in a closed-loop interferometer

    International Nuclear Information System (INIS)

    Jo, Sanghyun; Chang, Dong-In; Lee, Hu-Jong; Khym, Gyong Luck; Kang, Kicheon; Chung, Yunchul; Mahalu, Diana; Umansky, Vladimir

    2007-01-01

    One of the points at issue with closed-loop-type interferometers is beating in the Aharonov-Bohm (AB) oscillations. Recent observations suggest the possibility that the beating results from the Berry-phase pickup by the conducting electrons in materials with the strong spin-orbit interaction (SOI). In this study, we also observed beats in the AB oscillations in a gate-defined closed-loop interferometer fabricated on a GaAs/Al 0.3 Ga 0.7 As two-dimensional electron-gas heterostructure. Since this heterostructure has very small SOI, the picture of the Berry-phase pickup is ruled out. The observation of beats in this study, with the controllability of forming a single transverse subband mode in both arms of our gate-defined interferometer, also rules out the often-claimed multiple transverse subband effect. It is observed that nodes of the beats with an h/2e period exhibit a parabolic distribution for varying the side gate. These results are shown to be well interpreted, without resorting to the SOI effect, by the existence of two-dimensional multiple longitudinal modes in a single transverse subband. The Fourier spectrum of measured conductance, despite showing multiple h/e peaks with the magnetic-field dependence that are very similar to that from strong-SOI materials, can also be interpreted as the two-dimensional multiple-longitudinal-modes effect

  12. Global beta-beating compensation of the ALS W16 wiggler

    International Nuclear Information System (INIS)

    Robin, D.; Decking, W.; Nishimura, H.

    1997-05-01

    The W16 wiggler is the first wiggler and highest field insertion device to be installed in the ALS storage ring. When the gaps of the W16 wiggler are closed, the vertical tune increases by 0.065 and the vertical beta function is distorted by up to ±37%. There are 48 quadrupoles in the ring whose fields can be adjusted individually to restore the tunes and partially compensate the beta-beating. In order to adjust the quadrupole field strengths to accurately compensate the focusing, it is necessary to have a method to precisely determine the beta-beating. In this paper we compare measurements of the induced beta-beating using two methods: measuring the tune dependence on quadrupole field strength and fitting a lattice model with measured response matrices. The fitted model also allows us to predict quadrupole field strengths that will best compensate the beta beating. These quadrupole field strengths are then applied and the resultant beta-beating is measured

  13. 4D ultrasound and 3D MRI registration of beating heart

    International Nuclear Information System (INIS)

    Herlambang, N.; Matsumiya, K.; Masamune, K.; Dohi, T.; Liao, H.; Tsukihara, H.; Takamoto, S.

    2007-01-01

    To realize intra-cardiac surgery without cardio-pulmonary bypass, a medical imaging technique with both high image quality and data acquisition rate that is fast enough to follow heart beat movements is required. In this research, we proposed a method that utilized the image quality of MRI and the speed of ultrasound. We developed a 4D image reconstruction method using image registration of 3D MRI and 4D ultrasound images. The registration method consists of rigid registration between 3D MRI and 3D ultrasound with the same heart beat phase, and non-rigid registration between 3D ultrasound images from different heart beat phases. Non-rigid registration was performed with B-spline based registration using variable spring model. In phantom experiment using balloon phantom, registration accuracy was less than 2 mm for total heart volume variation range of 10%. We applied our registration method on 3D MRI and 4D ultrasound images of a volunteer's beating heart data and confirmed through visual observation that heart beat pattern was well reproduced. (orig.)

  14. Beat Synchronization across the Lifespan: Intersection of Development and Musical Experience.

    Directory of Open Access Journals (Sweden)

    Elaine C Thompson

    Full Text Available Rhythmic entrainment, or beat synchronization, provides an opportunity to understand how multiple systems operate together to integrate sensory-motor information. Also, synchronization is an essential component of musical performance that may be enhanced through musical training. Investigations of rhythmic entrainment have revealed a developmental trajectory across the lifespan, showing synchronization improves with age and musical experience. Here, we explore the development and maintenance of synchronization in childhood through older adulthood in a large cohort of participants (N = 145, and also ask how it may be altered by musical experience. We employed a uniform assessment of beat synchronization for all participants and compared performance developmentally and between individuals with and without musical experience. We show that the ability to consistently tap along to a beat improves with age into adulthood, yet in older adulthood tapping performance becomes more variable. Also, from childhood into young adulthood, individuals are able to tap increasingly close to the beat (i.e., asynchronies decline with age, however, this trend reverses from younger into older adulthood. There is a positive association between proportion of life spent playing music and tapping performance, which suggests a link between musical experience and auditory-motor integration. These results are broadly consistent with previous investigations into the development of beat synchronization across the lifespan, and thus complement existing studies and present new insights offered by a different, large cross-sectional sample.

  15. Reduced ischemia-reperfusion injury with isoproterenol in non-heart-beating donor lungs.

    Science.gov (United States)

    Jones, D R; Hoffmann, S C; Sellars, M; Egan, T M

    1997-05-01

    Transplantation of lungs retrieved from non-heart-beating donors could expand the donor pool. Recent studies suggest that the ischemia-reperfusion injury (IRI) to the lung can be attenuated by increasing intracellular cAMP concentrations. The purpose of this study was to determine the effect of IRI on capillary permeability, as measured by Kfc, in lungs retrieved from non-heart-beating donors and reperfused with or without isoproterenol (iso). Using an in situ isolated perfused lung model, lungs were retrieved from non-heart-beating donor rats ventilated with O2 or not at varying intervals after death. The lungs were reperfused with or without iso (10 microM). Kfc, lung viability, and pulmonary hemodynamics were measured, and tissue levels of adenine nucleotides and cAMP were measured by HPLC. Iso-reperfusion decreased Kfc significantly (P Kfc in non-iso-reperfused (r = 0.65) and iso-perfused (r = 0.84) lungs. cAMP levels increased significantly with iso-reperfusion. cAMP levels correlated with Kfc (r = 0.87) in iso-reperfused lungs. Iso-reperfusion of lungs retrieved from non-heart-beating donor rats results in decreased capillary permeability and increased lung tissue cAMP levels. Pharmacologic augmentation of tissue TAN and cAMP levels may further ameliorate the increased capillary permeability seen in lungs retrieved from non-heart-beating donors.

  16. Exhaled breath analysis using electronic nose in cystic fibrosis and primary ciliary dyskinesia patients with chronic pulmonary infections

    DEFF Research Database (Denmark)

    Joensen, Odin; Paff, Tamara; Haarman, Eric G

    2014-01-01

    The current diagnostic work-up and monitoring of pulmonary infections may be perceived as invasive, is time consuming and expensive. In this explorative study, we investigated whether or not a non-invasive exhaled breath analysis using an electronic nose would discriminate between cystic fibrosis...... (CF) and primary ciliary dyskinesia (PCD) with or without various well characterized chronic pulmonary infections. We recruited 64 patients with CF and 21 with PCD based on known chronic infection status. 21 healthy volunteers served as controls. An electronic nose was employed to analyze exhaled......, this method significantly discriminates CF patients suffering from a chronic pulmonary P. aeruginosa (PA) infection from CF patients without a chronic pulmonary infection. Further studies are needed for verification and to investigate the role of electronic nose technology in the very early diagnostic workup...

  17. Diode-pumped dual-frequency microchip Nd : YAG laser with tunable frequency difference

    Energy Technology Data Exchange (ETDEWEB)

    Ren Cheng; Zhang Shulian, E-mail: ren-c06@mails.tsinghua.edu.c [State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084 (China)

    2009-08-07

    The diode-pumped dual-frequency microchip Nd : YAG laser with tunable frequency difference is presented. The gain medium used is a microchip 2 mm in thickness for miniaturized and integrated design. Two quarter-wave plates are placed into the laser cavity and the intra-cavity birefringence produces two orthogonally linearly polarized modes. The rotation of one of the two quarter-wave plates introduces a controlled and variable cavity birefringence which causes a variable frequency difference between the two orthogonally polarized modes. The frequency difference can be tuned through the whole cavity free spectral range. The obtained frequency difference ranges from 14 MHz to 1.5 GHz. The variation of the beat frequency over a period of 10 min is less than 10 kHz. The lock-in between modes is not found. Experimental results are presented, which match well with the theoretical analysis based on Jones matrices.

  18. Measurements of beat wave accelerated electrons in a toroidal plasma

    International Nuclear Information System (INIS)

    Rogers, J.H.

    1992-06-01

    Electrons are accelerated by large amplitude electron plasma waves driven by counter-propagating microwaves with a difference frequency approximately equal to the electron plasma frequency. Energetic electrons are observed only when the phase velocity of the wave is in the range 3v e ph e (v ph was varied 2v e ph e ), where v e is the electron thermal velocity, (kT e /m e ) 1/2 . As the phase velocity increases, fewer electrons are accelerated to higher velocities. The measured current contained in these accelerated electrons has the power dependence predicted by theory, but the magnitude is lower than predicted

  19. Long-term follow-up of patients with retinitis pigmentosa (RP) receiving intraocular ciliary neurotrophic factor implants

    Science.gov (United States)

    Birch, David G.; Bennett, Lea D.; Duncan, Jacque L.; Weleber, Richard G.; Pennesi, Mark E.

    2016-01-01

    Purpose To evaluate the long-term efficacy of ciliary neurotrophic factor delivered via an intraocular encapsulated cell implant for the treatment of retinitis pigmentosa (RP). Design Long-term follow up of a multicenter, sham-controlled study. Methods Thirty-six patients at three CNTF4 sites were randomly assigned to receive a high- or low- dose implant in one eye and sham surgery in the fellow eye. The primary endpoint (change in visual field sensitivity at 12 months) has been reported previously.1 Here we report long-term visual acuity, visual field and optical coherence tomography (OCT) outcomes in 24 patients either retaining or explanting the device at 24 months relative to sham-treated eyes. Results Eyes retaining the implant showed significantly greater visual field loss from baseline than either explanted eyes or sham eyes through 42 months. By 60 months and continuing through 96 months, visual field loss was comparable among sham-treated eyes, eyes retaining the implant and explanted eyes, as was visual acuity and OCT macular volume. Conclusions Over the short term, ciliary neurotrophic factor released continuously from an intra-vitreal implant lead to loss of total visual field sensitivity that was greater than the natural progression in the sham-treated eye. This additional loss of sensitivity related to the active implant was reversible when the implant was removed. Over the long term (60 – 96 months), there was no evidence of efficacy for visual acuity, visual field sensitivity or OCT measures of retinal structure. PMID:27457255

  20. The development of the larval nervous system, musculature and ciliary bands of Pomatoceros lamarckii (Annelida: heterochrony in polychaetes

    Directory of Open Access Journals (Sweden)

    Shimeld Sebastian M

    2006-10-01

    Full Text Available Abstract Background To understand the evolution of animals it is essential to have taxon sampling across a representative spread of the animal kingdom. With the recent rearrangement of most of the Bilateria into three major clades (Ecdysozoa, Lophotrochozoa and Deuterostomia it has become clear that the Lophotrochozoa are relatively poorly represented in our knowledge of animal development, compared to the Ecdysozoa and Deuterostomia. We aim to contribute towards redressing this balance with data on the development of the muscular, nervous and ciliary systems of the annelid Pomatoceros lamarckii (Serpulidae. We compare our data with other lophotrochozoans. Results P. lamarckii develops locomotory and feeding structures that enable it to become a swimming, planktotrophic larva within 24 hours. Formation of the trochophore includes development of a prototroch, metatroch and neurotroch, development of apical and posterior nervous elements at similar times, and development of musculature around the ciliary bands and digestive tract prior to development of any body wall muscles. The adult nervous and muscular systems are essentially preformed in the late larva. Interestingly, the muscular systems of the larvae and juvenile worms do not include the circular muscles of the body wall, which are considered to be plesiomorphic for annelids, although the possibility that circular muscles develop after these stages cannot be ruled out at this point. Conclusion A comparison between polychaetes shows variability in the timing (heterochrony of development of body wall muscles and elements of the nervous system. These heterochronies are one route for evolution of different life history strategies, such as adaptations to feeding requirements.

  1. A novel type of self-beating cardiomyocytes in adult mouse ventricles

    International Nuclear Information System (INIS)

    Omatsu-Kanbe, Mariko; Matsuura, Hiroshi

    2009-01-01

    This study was designed to investigate the presence of resident heart cells that are distinct from terminally-differentiated cardiomyocytes. Adult mouse heart was coronary perfused with collagenase, and ventricles were excised and further digested. After spinning cardiomyocyte-containing fractions down, the supernatant fraction was collected and cultured without adding any chemicals. Two to five days after plating, some of rounded cells adhered to the culture dish, gradually changed their shape and then started self-beating. These self-beating cells did not appreciably proliferate but underwent a further morphological maturation process to form highly branched shapes with many projections. These cells were mostly multinucleated, well sarcomeric-organized and expressed cardiac marker proteins, defined as atypically-shaped cardiomyocytes (ACMs). Patch-clamp experiments revealed that ACMs exhibited spontaneous action potentials arising from the preceding slow diastolic depolarization. We thus found a novel type of resident heart cells in adult cardiac ventricles that spontaneously develop into self-beating cardiomyocytes.

  2. Cross-Cultural Influences on Rhythm Processing: Reproduction, Discrimination, and Beat Tapping

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2015-04-01

    Full Text Available The structures of musical rhythm differ between cultures, despite the fact that the ability to synchronize one’s movements to musical rhythms appears to be universal. To measure the influence of culture on rhythm processing, we tested East African and North American adults on the perception, production, and beat tapping of rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced both by the culture of the participant and by the culture of the rhythm. Specifically, we predicted that a participant’s ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than unfamiliar rhythms. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion.

  3. Activating and relaxing music entrains the speed of beat synchronized walking.

    Science.gov (United States)

    Leman, Marc; Moelants, Dirk; Varewyck, Matthias; Styns, Frederik; van Noorden, Leon; Martens, Jean-Pierre

    2013-01-01

    Inspired by a theory of embodied music cognition, we investigate whether music can entrain the speed of beat synchronized walking. If human walking is in synchrony with the beat and all musical stimuli have the same duration and the same tempo, then differences in walking speed can only be the result of music-induced differences in stride length, thus reflecting the vigor or physical strength of the movement. Participants walked in an open field in synchrony with the beat of 52 different musical stimuli all having a tempo of 130 beats per minute and a meter of 4 beats. The walking speed was measured as the walked distance during a time interval of 30 seconds. The results reveal that some music is 'activating' in the sense that it increases the speed, and some music is 'relaxing' in the sense that it decreases the speed, compared to the spontaneous walked speed in response to metronome stimuli. Participants are consistent in their observation of qualitative differences between the relaxing and activating musical stimuli. Using regression analysis, it was possible to set up a predictive model using only four sonic features that explain 60% of the variance. The sonic features capture variation in loudness and pitch patterns at periods of three, four and six beats, suggesting that expressive patterns in music are responsible for the effect. The mechanism may be attributed to an attentional shift, a subliminal audio-motor entrainment mechanism, or an arousal effect, but further study is needed to figure this out. Overall, the study supports the hypothesis that recurrent patterns of fluctuation affecting the binary meter strength of the music may entrain the vigor of the movement. The study opens up new perspectives for understanding the relationship between entrainment and expressiveness, with the possibility to develop applications that can be used in domains such as sports and physical rehabilitation.

  4. Activating and relaxing music entrains the speed of beat synchronized walking.

    Directory of Open Access Journals (Sweden)

    Marc Leman

    Full Text Available Inspired by a theory of embodied music cognition, we investigate whether music can entrain the speed of beat synchronized walking. If human walking is in synchrony with the beat and all musical stimuli have the same duration and the same tempo, then differences in walking speed can only be the result of music-induced differences in stride length, thus reflecting the vigor or physical strength of the movement. Participants walked in an open field in synchrony with the beat of 52 different musical stimuli all having a tempo of 130 beats per minute and a meter of 4 beats. The walking speed was measured as the walked distance during a time interval of 30 seconds. The results reveal that some music is 'activating' in the sense that it increases the speed, and some music is 'relaxing' in the sense that it decreases the speed, compared to the spontaneous walked speed in response to metronome stimuli. Participants are consistent in their observation of qualitative differences between the relaxing and activating musical stimuli. Using regression analysis, it was possible to set up a predictive model using only four sonic features that explain 60% of the variance. The sonic features capture variation in loudness and pitch patterns at periods of three, four and six beats, suggesting that expressive patterns in music are responsible for the effect. The mechanism may be attributed to an attentional shift, a subliminal audio-motor entrainment mechanism, or an arousal effect, but further study is needed to figure this out. Overall, the study supports the hypothesis that recurrent patterns of fluctuation affecting the binary meter strength of the music may entrain the vigor of the movement. The study opens up new perspectives for understanding the relationship between entrainment and expressiveness, with the possibility to develop applications that can be used in domains such as sports and physical rehabilitation.

  5. Activating and Relaxing Music Entrains the Speed of Beat Synchronized Walking

    Science.gov (United States)

    Leman, Marc; Moelants, Dirk; Varewyck, Matthias; Styns, Frederik; van Noorden, Leon; Martens, Jean-Pierre

    2013-01-01

    Inspired by a theory of embodied music cognition, we investigate whether music can entrain the speed of beat synchronized walking. If human walking is in synchrony with the beat and all musical stimuli have the same duration and the same tempo, then differences in walking speed can only be the result of music-induced differences in stride length, thus reflecting the vigor or physical strength of the movement. Participants walked in an open field in synchrony with the beat of 52 different musical stimuli all having a tempo of 130 beats per minute and a meter of 4 beats. The walking speed was measured as the walked distance during a time interval of 30 seconds. The results reveal that some music is ‘activating’ in the sense that it increases the speed, and some music is ‘relaxing’ in the sense that it decreases the speed, compared to the spontaneous walked speed in response to metronome stimuli. Participants are consistent in their observation of qualitative differences between the relaxing and activating musical stimuli. Using regression analysis, it was possible to set up a predictive model using only four sonic features that explain 60% of the variance. The sonic features capture variation in loudness and pitch patterns at periods of three, four and six beats, suggesting that expressive patterns in music are responsible for the effect. The mechanism may be attributed to an attentional shift, a subliminal audio-motor entrainment mechanism, or an arousal effect, but further study is needed to figure this out. Overall, the study supports the hypothesis that recurrent patterns of fluctuation affecting the binary meter strength of the music may entrain the vigor of the movement. The study opens up new perspectives for understanding the relationship between entrainment and expressiveness, with the possibility to develop applications that can be used in domains such as sports and physical rehabilitation. PMID:23874469

  6. Active Faraday optical frequency standard.

    Science.gov (United States)

    Zhuang, Wei; Chen, Jingbiao

    2014-11-01

    We propose the mechanism of an active Faraday optical clock, and experimentally demonstrate an active Faraday optical frequency standard based on narrow bandwidth Faraday atomic filter by the method of velocity-selective optical pumping of cesium vapor. The center frequency of the active Faraday optical frequency standard is determined by the cesium 6 (2)S(1/2) F=4 to 6 (2)P(3/2) F'=4 and 5 crossover transition line. The optical heterodyne beat between two similar independent setups shows that the frequency linewidth reaches 281(23) Hz, which is 1.9×10(4) times smaller than the natural linewidth of the cesium 852-nm transition line. The maximum emitted light power reaches 75 μW. The active Faraday optical frequency standard reported here has advantages of narrow linewidth and reduced cavity pulling, which can readily be extended to other atomic transition lines of alkali and alkaline-earth metal atoms trapped in optical lattices at magic wavelengths, making it useful for new generation of optical atomic clocks.

  7. Beat wave current drive experiment on the Davis Diverted Tokamak (DDT)

    International Nuclear Information System (INIS)

    Hwang, D.Q.; Horton, R.D.; Rogers, J.H.

    1993-01-01

    The beatwave current drive experiment is summarized. The first phase of the experiment was the construction of the microwave sources and the diagnostics needed to demonstrate the beat wave effects, i.e. the measurement of the electrostatic plasma wave produced by the beating of two high intensity electromagnetic waves. In order to keep the cost of the experiments to a minimum, a low density filament plasma source (10 8 ) to (10 10 particles cm -3 ) was employed and the magnetic field in the toroidal plasma was produced by a dc power supply

  8. Electron non-linearities in Langmuir waves with application to beat-wave experiments

    International Nuclear Information System (INIS)

    Bell, A.R.; Gibbon, P.

    1988-01-01

    Non-linear Langmuir waves are examined in the context of the beat-wave accelerator. With a background of immobile ions the waves in one dimension are subject to the relativistic non-linearity of Rosenbluth, M.N. and Liu, C.S., Phys. Rev. Lett., 1972, 29, 701. In two or three dimensions, other electron non-linearities occur which involve electric and magnetic fields. The quasi-linear equations for these non-linearities are developed and solved numerically in a geometry representative of laser-driven beat waves. (author)

  9. Beat-to-beat ECG restitution: A review and proposal for a new biomarker to assess cardiac stress and ventricular tachyarrhythmia vulnerability.

    Science.gov (United States)

    Fossa, Anthony A

    2017-09-01

    Cardiac restitution is the ability of the heart to recover from one beat to the next. Ventricular arrhythmia vulnerability can occur when the heart does not properly adjust to sudden changes in rate or in hemodynamics leading to excessive temporal and/or spatial heterogeneity in conduction or repolarization. Restitution has historically been used to study, by invasive means, the dynamics of the relationship between action potential duration (APD) and diastolic interval (DI) in sedated subjects using various pacing protocols. Even though the analogous measures of APD and DI can be obtained using the surface ECG to acquire the respective QT and TQ intervals for ECG restitution, this methodology has not been widely adopted for a number of reasons. Recent development of more advanced software algorithms enables ECG intervals to be measured accurately, on a continuous beat-to-beat basis, in an automated manner, and under highly dynamic conditions (i.e., ambulatory or exercise) providing information beyond that available in the typical resting state. Current breakthroughs in ECG technology will allow ECG restitution measures to become a practical approach for providing quantitative measures of the risks for ventricular arrhythmias as well as cardiac stress in general. In addition to a review of the underlying principles and caveats of ECG restitution, a new approach toward an advancement of more integrated restitution biomarkers is proposed. © 2017 Wiley Periodicals, Inc.

  10. Beating speckles” via electrically-induced vibrations of Au nanorods embedded in sol-gel

    Science.gov (United States)

    Ritenberg, Margarita; Beilis, Edith; Ilovitsh, Asaf; Barkai, Zehava; Shahmoon, Asaf; Richter, Shachar; Zalevsky, Zeev; Jelinek, Raz

    2014-01-01

    Generation of macroscopic phenomena through manipulating nano-scale properties of materials is among the most fundamental goals of nanotechnology research. We demonstrate cooperative “speckle beats” induced through electric-field modulation of gold (Au) nanorods embedded in a transparent sol-gel host. Specifically, we show that placing the Au nanorod/sol-gel matrix in an alternating current (AC) field gives rise to dramatic modulation of incident light scattered from the material. The speckle light patterns take form of “beats”, for which the amplitude and frequency are directly correlated with the voltage and frequency, respectively, of the applied AC field. The data indicate that the speckle beats arise from localized vibrations of the gel-embedded Au nanorods, induced through the interactions between the AC field and the electrostatically-charged nanorods. This phenomenon opens the way for new means of investigating nanoparticles in constrained environments. Applications in electro-optical devices, such as optical modulators, movable lenses, and others are also envisaged. PMID:24413086

  11. Binaural Beat Technology: A Complementary Path to Post Deployment Wellness

    Science.gov (United States)

    2017-03-16

    study (McConnell, 2014). Using a slightly similar design and BBT in the same theta brainwave frequency, efficacy was assessed using a “ physical ...technology is unassuming, as it appears as though the service member is simply listening to music. Principal Investigator: Gantt, MeLisa A LTC (ret...31 (82%) 22 (61%) Marital Status Single 8 (22%) 9 (25%) 0.727 Separated 2 (5%) 4 (11%) Divorced 5 (14%) 3 (8%) Married 22 (60%) 20 (56

  12. Disentangling beat perception from sequential learning and examining the influence of attention and musical abilities on ERP responses to rhythm

    NARCIS (Netherlands)

    Bouwer, F.L.; Werner, C.M.; Knetemann, M.; Honing, H.

    Beat perception is the ability to perceive temporal regularity in musical rhythm. When a beat is perceived, predictions about upcoming events can be generated. These predictions can influence processing of subsequent rhythmic events. However, statistical learning of the order of sounds in a sequence

  13. Mnemonic Effect of Iconic Gesture and Beat Gesture in Adults and Children: Is Meaning in Gesture Important for Memory Recall?

    Science.gov (United States)

    So, Wing Chee; Chen-Hui, Colin Sim; Wei-Shan, Julie Low

    2012-01-01

    Abundant research has shown that encoding meaningful gesture, such as an iconic gesture, enhances memory. This paper asked whether gesture needs to carry meaning to improve memory recall by comparing the mnemonic effect of meaningful (i.e., iconic gestures) and nonmeaningful gestures (i.e., beat gestures). Beat gestures involve simple motoric…

  14. Comparative effect of mechanical beating and nanofibrillation of cellulose on paper properties made from bagasse and softwood pulps.

    Science.gov (United States)

    Afra, Elyas; Yousefi, Hossein; Hadilam, Mohamad Mahdi; Nishino, Takashi

    2013-09-12

    Cellulose fibers were fibrillated using mechanical beating (shearing refiner) and ultra-fine friction grinder, respectively. The fibrillated fibers were then used to make paper. Mechanical beating process created a partial skin fibrillation, while grinding turned fiber from micro to nanoscale through nanofibrillation mechanism. The partially fibrillated and nano fibrillated fibers had significant effects on paper density, tear strength, tensile strength and water drainage time. The effect of nanofibrillation on paper properties was quantitatively higher than that of mechanical beating. Paper sheets from nanofibrillated cellulose have a higher density, higher tensile strength and lower tear strength compared to those subjected to mechanical beating. Mechanical beating and nanofibrillation were both found to be promising fiber structural modifications. Long water drainage time was an important drawback of both fibrillation methods. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Childhood exposure to domestic violence and attitude towards wife beating in adult life: a study of men in India.

    Science.gov (United States)

    Zhu, Ying; Dalal, Koustuv

    2010-03-01

    This study examined men's justification of wife beating in relation to their perceived rights and autonomy using a nationally representative sample of 18,047 men in India with childhood exposure to parental violence. Five reasons for wife beating justification, four items of men's perceived rights, and five items of household autonomy were analysed using chi2 test and logistic regression. Among 18,047 participants, 67% justified wife beating. Low education, economic stress and being unmarried were generally more associated with justifying wife beating for all five reasons. Wife's refusal of sex and husband's final say on household autonomy are risk factors. Joint autonomy on household decision making and wife's autonomy on managing her own earnings are protective factors. Perceived relationship rights and autonomy are highly predictive of wife-beating justification for the men who have been exposed to parental violence during childhood. The study has significant implications for public health planners and education strategies.

  16. Multivariate Autoregressive Model Based Heart Motion Prediction Approach for Beating Heart Surgery

    Directory of Open Access Journals (Sweden)

    Fan Liang

    2013-02-01

    Full Text Available A robotic tool can enable a surgeon to conduct off-pump coronary artery graft bypass surgery on a beating heart. The robotic tool actively alleviates the relative motion between the point of interest (POI on the heart surface and the surgical tool and allows the surgeon to operate as if the heart were stationary. Since the beating heart's motion is relatively high-band, with nonlinear and nonstationary characteristics, it is difficult to follow. Thus, precise beating heart motion prediction is necessary for the tracking control procedure during the surgery. In the research presented here, we first observe that Electrocardiography (ECG signal contains the causal phase information on heart motion and non-stationary heart rate dynamic variations. Then, we investigate the relationship between ECG signal and beating heart motion using Granger Causality Analysis, which describes the feasibility of the improved prediction of heart motion. Next, we propose a nonlinear time-varying multivariate vector autoregressive (MVAR model based adaptive prediction method. In this model, the significant correlation between ECG and heart motion enables the improvement of the prediction of sharp changes in heart motion and the approximation of the motion with sufficient detail. Dual Kalman Filters (DKF estimate the states and parameters of the model, respectively. Last, we evaluate the proposed algorithm through comparative experiments using the two sets of collected vivo data.

  17. Analytic methods to find beating transitions of asymmetric Gaussian beams in GNLS equations

    Science.gov (United States)

    Ianetz, David; Schiff, Jeremy

    2018-01-01

    In a simple model of propagation of asymmetric Gaussian beams in nonlinear waveguides, described by a reduction to ordinary differential equations of generalized nonlinear Schrödinger equations with cubic-quintic (CQ) and saturable (SAT) nonlinearities and a graded-index profile, the beam widths exhibit two different types of beating behavior, with transitions between them. We present an analytic model to explain these phenomena, which originate in a 1:1 resonance in a 2 degree-of-freedom Hamiltonian system. We show how small oscillations near a fixed point close to 1:1 resonance in such a system can be approximated using an integrable Hamiltonian and, ultimately, a single first order differential equation. In particular, the beating transitions can be located from coincidences of roots of a pair of quadratic equations, with coefficients determined (in a highly complex manner) by the internal parameters and initial conditions of the original system. The results of the analytic model agree with the numerics of the original system over large parameter ranges, and allow new predictions that can be verified directly. In the CQ case, we identify a band of beam energies for which there is only a single beating transition (as opposed to 0 or 2) as the eccentricity is increased. In the SAT case, we explain the sudden (dis)appearance of beating transitions for certain values of the other parameters as the grade-index is changed.

  18. A new beating-heart off-pump coronary artery bypass grafting training model

    NARCIS (Netherlands)

    Bouma, Wobbe; Kuijpers, Michiel; Bijleveld, Aanke; De Maat, Gijs E.; Koene, Bart M.; Erasmus, Michiel E.; Natour, Ehsan; Mariani, Massimo A.

    OBJECTIVES: Training models are essential in mastering the skills required for off-pump coronary artery bypass grafting (OPCAB). We describe a new, high-fidelity, effective and reproducible beating-heart OPCAB training model in human cadavers. METHODS: Human cadavers were embalmed according to the

  19. Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins

    NARCIS (Netherlands)

    Namdeo, S.; Onck, P. R.

    2016-01-01

    Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins,

  20. Beat Keeping in a Sea Lion As Coupled Oscillation: Implications for Comparative Understanding of Human Rhythm.

    Science.gov (United States)

    Rouse, Andrew A; Cook, Peter F; Large, Edward W; Reichmuth, Colleen

    2016-01-01

    Human capacity for entraining movement to external rhythms-i.e., beat keeping-is ubiquitous, but its evolutionary history and neural underpinnings remain a mystery. Recent findings of entrainment to simple and complex rhythms in non-human animals pave the way for a novel comparative approach to assess the origins and mechanisms of rhythmic behavior. The most reliable non-human beat keeper to date is a California sea lion, Ronan, who was trained to match head movements to isochronous repeating stimuli and showed spontaneous generalization of this ability to novel tempos and to the complex rhythms of music. Does Ronan's performance rely on the same neural mechanisms as human rhythmic behavior? In the current study, we presented Ronan with simple rhythmic stimuli at novel tempos. On some trials, we introduced "perturbations," altering either tempo or phase in the middle of a presentation. Ronan quickly adjusted her behavior following all perturbations, recovering her consistent phase and tempo relationships to the stimulus within a few beats. Ronan's performance was consistent with predictions of mathematical models describing coupled oscillation: a model relying solely on phase coupling strongly matched her behavior, and the model was further improved with the addition of period coupling. These findings are the clearest evidence yet for parity in human and non-human beat keeping and support the view that the human ability to perceive and move in time to rhythm may be rooted in broadly conserved neural mechanisms.

  1. The Ability to Tap to a Beat Relates to Cognitive, Linguistic, and Perceptual Skills

    Science.gov (United States)

    Tierney, Adam T.; Kraus, Nina

    2013-01-01

    Reading-impaired children have difficulty tapping to a beat. Here we tested whether this relationship between reading ability and synchronized tapping holds in typically-developing adolescents. We also hypothesized that tapping relates to two other abilities. First, since auditory-motor synchronization requires monitoring of the relationship…

  2. Beating the baseline prediction in food sales : how intelligent an intelligent predictor is?

    NARCIS (Netherlands)

    Zliobaite, I.; Bakker, J.; Pechenizkiy, M.

    2012-01-01

    Sales prediction is an essential part of stock planning for the wholesales and retail business. It is a complex task because of the large number of factors affecting the demand. Designing an intelligent predictor that would beat a simple moving average baseline across a number of products appears to

  3. Effects of Movement, Tempo, and Gender on Steady Beat Performance of Kindergarten Children

    Science.gov (United States)

    Rose, Paige

    2016-01-01

    The purposes of this research were to discover the effects of manual (hand) and pedal (foot) movements, tempo, and gender on steady beat accuracy. Participants (N = 119) consisted of male (n = 63) and female (n = 56) kindergarten students randomly divided into two groups, counterbalanced with regard to school, homeroom, and gender. Participants…

  4. The Roles of Traditional Gender Myths and Beliefs About Beating on Self-Reported Partner Violence.

    Science.gov (United States)

    Husnu, Shenel; Mertan, Biran E

    2015-08-24

    The aim of the current study was to investigate the roles of beliefs about beating, traditional gender myth endorsement, ambivalent sexism, and perceived partner violence in determining an individual's own reported violence toward his or her partner. The sample consisted of 205 (117 women; 88 men) Turkish and Turkish Cypriot undergraduate students, aged between 16 and 29 years. Participants completed measures of beliefs about beating, traditional gender myth endorsement, and ambivalent sexism and rated the extent to which they experienced abusive behaviors from their partner as well as the extent to which they were themselves abusive to their partners. Results showed that positive beliefs about beating, endorsing traditional gender myths, and experiencing partner abuse were all predictive of self-reported abuse to one's partner. Furthermore, the relationship between myth endorsement and self-abusive behavior was mediated by beliefs toward beating-only in men. Results are discussed in light of the traditional gender system evident in Turkish societal makeup. © The Author(s) 2015.

  5. Why Some Schools with Latino Children Beat the Odds...and Others Don't

    Science.gov (United States)

    Waits, Mary Jo; Campbell, Heather E.; Gau, Rebecca; Jacobs, Ellen; Rex, Tom; Hess, Robert K.

    2006-01-01

    Throughout Arizona and the Southwest, the odds are against high achievement in schools with a mostly Latino, mostly poor student enrollment. Some schools, however, "beat the odds" and achieve consistently high results or show steady gains. Why do these schools succeed where others fail? Using the methodology of business guru Jim Collins…

  6. A continuum model for flow induced by metachronal coordination between beating cilia

    NARCIS (Netherlands)

    Hussong, J.; Breugem, W.P.; Westerweel, J.

    2011-01-01

    In this numerical study we investigate the flow induced by metachronal coordination between beating cilia arranged in a densely packed layer by means of a continuum model. The continuum approach allows us to treat the problem as two-dimensional as well as stationary, in a reference frame moving with

  7. The Patterns of Music: Young Children Learning Mathematics through Beat, Rhythm, and Melody

    Science.gov (United States)

    Geist, Kamile; Geist, Eugene A.; Kuznik, Kathleen

    2012-01-01

    Research on music and music therapy suggests that math and music are related in the brain from very early in life. Musical elements such as steady beat, rhythm, melody, and tempo possess inherent mathematical principles such as spatial properties, sequencing, counting, patterning, and one-to-one correspondence. With new understanding about the…

  8. Beat Synchronization across the Lifespan: Intersection of Development and Musical Experience

    OpenAIRE

    Thompson, Elaine C.; White-Schwoch, Travis; Tierney, Adam; Kraus, Nina

    2015-01-01

    Rhythmic entrainment, or beat synchronization, provides an opportunity to understand how multiple systems operate together to integrate sensory-motor information. Also, synchronization is an essential component of musical performance that may be enhanced through musical training. Investigations of rhythmic entrainment have revealed a developmental trajectory across the lifespan, showing synchronization improves with age and musical experience. Here, we explore the development and maintenance ...

  9. Tagasiviitavad tõendid: teine pilk pilditeadusele / Beat Wyss ; intervjueerinud Ivar-Kristjan Hein

    Index Scriptorium Estoniae

    Wyss, Beat, 1947-

    2011-01-01

    Intervjuus Karlsruhe kunsti- ja disainiülikooli kunstiajaloo ja meediateooria professori Beat Wyssiga on teemaks Zürichis tema juhitav uurimisprojekt, mille keskmes on Venezia biennaal Ida-Euroopa riikide positsioonilt, tema EKA Kunstiteaduse Instituudi doktorantidele peetud seminar "Tagasiviitavad tõendid. Teine pilk pilditeadusele", tema kaasaegse kunsti universaalsed põhimõtted

  10. The Effects of Visual Beats on Prosodic Prominence: Acoustic Analyses, Auditory Perception and Visual Perception

    Science.gov (United States)

    Krahmer, Emiel; Swerts, Marc

    2007-01-01

    Speakers employ acoustic cues (pitch accents) to indicate that a word is important, but may also use visual cues (beat gestures, head nods, eyebrow movements) for this purpose. Even though these acoustic and visual cues are related, the exact nature of this relationship is far from well understood. We investigate whether producing a visual beat…

  11. Amplitude differences least squares method applied to temporal cardiac beat alignment

    International Nuclear Information System (INIS)

    Correa, R O; Laciar, E; Valentinuzzi, M E

    2007-01-01

    High resolution averaged ECG is an important diagnostic technique in post-infarcted and/or chagasic patients with high risk of ventricular tachycardia (VT). It calls for precise determination of the synchronism point (fiducial point) in each beat to be averaged. Cross-correlation (CC) between each detected beat and a reference beat is, by and large, the standard alignment procedure. However, the fiducial point determination is not precise in records contaminated with high levels of noise. Herein, we propose an alignment procedure based on the least squares calculation of the amplitude differences (LSAD) between the ECG samples and a reference or template beat. Both techniques, CC and LSAD, were tested in high resolution ECG's corrupted with white noise and 50 Hz line interference of varying amplitudes (RMS range: 0-100μV). Results point out that LSDA produced a lower alignment error in all contaminated records while in those blurred by power line interference better results were found only within the 0-40 μV range. It is concluded that the proposed method represents a valid alignment alternative

  12. Attitudes toward Wife Beating: A Cross-Country Study in Asia

    Science.gov (United States)

    Rani, Manju; Bonu, Sekhar

    2009-01-01

    Using demographic and health surveys conducted between 1998 and 2001 from seven countries (Armenia, Bangladesh, Cambodia, India, Kazakhstan, Nepal, and Turkey), the study found that acceptance of wife beating ranged from 29% in Nepal, to 57% in India (women only), and from 26% in Kazakhstan, to 56% in Turkey (men only). Increasing wealth predicted…

  13. Ratings of speed in real music as a function of both original and manipulated beat tempo.

    Science.gov (United States)

    Madison, Guy; Paulin, Johan

    2010-11-01

    There is an apparent contradiction between the narrow range of tempi optimal for perceptual judgment and motor synchronization and the wide range of beat tempi found in real music. The relation between listeners' perception of speed and beat tempo was therefore investigated, both for real music excerpts (ME) and metronome sequences. Tempi ranged from 42 to 200 beats per minute (BPM), and some excerpts were further tempo manipulated in four levels from ±5 to ±20%. Regression analyses showed that speed was a shallower function of original tempo for fast (>150 BPM) and slow (tempo had twice as large an effect on speed as had original tempo. In contrast, speed was an almost linear function of tempo for metronome sequences. Taken together, these results show that the non-linearity stems from properties of the musical signal, rather than being a subjective perceptual effect. They indicate an inverse relation between tempo and relative event density in real music, and demonstrate that the perception of periodic signals is affected not only by the beat level, but also by faster and slower levels.

  14. BEAT: A Web-Based Boolean Expression Fault-Based Test Case Generation Tool

    Science.gov (United States)

    Chen, T. Y.; Grant, D. D.; Lau, M. F.; Ng, S. P.; Vasa, V. R.

    2006-01-01

    BEAT is a Web-based system that generates fault-based test cases from Boolean expressions. It is based on the integration of our several fault-based test case selection strategies. The generated test cases are considered to be fault-based, because they are aiming at the detection of particular faults. For example, when the Boolean expression is in…

  15. Beat Keeping in a Sea Lion as Coupled Oscillation: Implications for Comparative Understanding of Human Rhythm

    Directory of Open Access Journals (Sweden)

    Andrew A Rouse

    2016-06-01

    Full Text Available Human capacity for entraining movement to external rhythms—i.e., beat keeping—is ubiquitous, but its evolutionary history and neural underpinnings remain a mystery. Recent findings of entrainment to simple and complex rhythms in non-human animals pave the way for a novel comparative approach to assess the origins and mechanisms of rhythmic behavior. The most reliable non-human beat keeper to date is a California sea lion, Ronan, who was trained to match head movements to isochronous repeating stimuli and showed spontaneous generalization of this ability to novel tempos and to the complex rhythms of music. Does Ronan’s performance rely on the same neural mechanisms as human rhythmic behavior? In the current study, we presented Ronan with simple rhythmic stimuli at novel tempos. On some trials, we introduced perturbations, altering either tempo or phase in the middle of a presentation. Ronan quickly adjusted her behavior following all perturbations, recovering her consistent phase and tempo relationships to the stimulus within a few beats. Ronan’s performance was consistent with predictions of mathematical models describing coupled oscillation: a model relying solely on phase coupling strongly matched her behavior, and the model was further improved with the addition of period coupling. These findings are the clearest evidence yet for parity in human and non-human beat keeping and support the view that the human ability to perceive and move in time to rhythm may be rooted in broadly conserved neural mechanisms.

  16. Non-heart-beating lung donation : How big is the pool?

    NARCIS (Netherlands)

    Nijkamp, Danielle M.; van der Bij, Wim; Verschuuren, Erik A. M.; Heemskerk, Martin B. A.; de Buijzer, Erwin; Erasmus, Michiel E.

    Lungs from non-heart-beating (NHB) donors are seldom used in The Netherlands despite the good quality of these organs. Based on a retrospective analysis of 162 NHB donor procedures we found that only 5% of the lungs were actually utilized, but that 30% of the lungs were suitable for transplantation.

  17. Siim Nestor soovitab : Stereo ÖÖ. Mutant Disco. Beats from the Vault. Turbodisko / Siim Nestor

    Index Scriptorium Estoniae

    Nestor, Siim, 1974-

    2006-01-01

    Oma debüütalbumit "Migration" tutvustav ameerika diskor Alex Attias üritustel "Stereo ÖÖ" 19. mail Tallinnas Von Krahlis. Üritustest "Mutant Disco" 19. mail Tallinnas klubis Privé ja Tartus 20. mail klubis Illusion, "Beats from the Vault" 19. mail Tallinnas klubis Võit ja "Turbodisko" 20. mail Tallinnas klubis KuKu

  18. Behind Beats and Rhymes: Working Class from a Hampton Roads Hip Hop Homeplace

    Science.gov (United States)

    Durham, Aisha S.

    2009-01-01

    The film documentary titled "Hip Hop: beyond beats and rhymes" captures ongoing conversations among scholars, cultural critics, and hip hop insiders about the state of African Americans by interrogating distinct expressive forms associated with hip hop culture. Durham draws from two scenes to describe her memories as the researched…

  19. Hyperglycemia in Streptozotocin-Induced Diabetes Leads to Persistent Inflammation and Tissue Damage Following Uveitis Due to Reduced Levels of Ciliary Body Heme Oxygenase-1

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available This study investigated the heme oxygenase-1 (HO-1 and the endotoxin-induced uveitis (EIU in diabetic streptozotocin (STZ-hyperglycemic rats. STZ-hyperglycemic rats had impaired levels of the enzyme HO-1 within the ciliary bodies if compared with the nondiabetic rats. STZ-hyperglycemic rats also predisposed the eye to produce high levels of both the cytokines IL-1 β and CXCL8. Subsequent EIU further and significantly P<.01 increased the cytokines production, an effect partly prevented by hemin treatment. Most importantly, hemin, an inducer of heme oxygenase expression and activity, recovered the huge number of infiltrated polymorphonuclear leukocytes PMN within the ciliary bodies associated with STZ-hyperglycemic state and EIU damage. Impairment of the stress-sensitive enzyme HO-1 in STZ-hyperglycemic rats increases and prolongs the inflammatory response to EIU.

  20. Beating the market with small portfolios: Evidence from Brazil

    Directory of Open Access Journals (Sweden)

    André A.P. Santos

    2015-01-01

    Full Text Available Optimal portfolios with a restriction on the number of assets, also referred to as cardinality-constrained portfolios, have been receiving attention in the literature due to its popularity among market practitioners and retail investors. In most cases, however, the interest is in proposing efficient optimization methods to solve the problem, with little or no attention to the characteristics of the resulting portfolio such as risk-adjusted performance and turnover. We address this question by implementing a tractable reformulation of the cardinality-constrained version of the minimum variance portfolio. We analyze the out-of-sample performance of cardinality-constrained portfolios according to alternative criteria and check the robustness of the results for portfolios with alternative number of assets and under alternative re-balancing frequencies. Our empirical application for the Brazilian equities market shows that cardinality-constrained minimum variance portfolios with very few assets, e.g. 3 stocks, can deliver statistically lower portfolio risk and higher Sharpe ratios in comparison to the market index. Similar results are obtained for constrained portfolios with 5 and 10 assets and under daily, weekly, and monthly re-balancing frequencies. Our evidence indicates that it is possible to obtain better risk-adjusted performance with fewer securities in the portfolio by using an improved allocation scheme.