WorldWideScience

Sample records for arterial tone effets

  1. Visceral periadventitial adipose tissue regulates arterial tone of mesenteric arteries.

    Science.gov (United States)

    Verlohren, Stefan; Dubrovska, Galyna; Tsang, Suk-Ying; Essin, Kirill; Luft, Friedrich C; Huang, Yu; Gollasch, Maik

    2004-09-01

    Periadventitial adipose tissue produces vasoactive substances that influence vascular contraction. Earlier studies addressed this issue in aorta, a vessel that does not contribute to peripheral vascular resistance. We tested the hypothesis that periadventitial adipose tissue modulates contraction of smaller arteries more relevant to blood pressure regulation. We studied mesenteric artery rings surrounded by periadventitial adipose tissue from adult male Sprague-Dawley rats. The contractile response to serotonin, phenylephrine, and endothelin I was markedly reduced in intact vessels compared with vessels without periadventitial fat. The contractile response to U46619 or depolarizing high K+-containing solutions (60 mmol/L) was similar in vessels with and without periadventitial fat. The K+ channel opener cromakalim induced relaxation of vessels precontracted by serotonin but not by U46619 or high K+-containing solutions (60 mmol/L), suggesting that K+ channels are involved. The intracellular membrane potential of smooth muscle cells was more hyperpolarized in intact vessels than in vessels without periadventitial fat. Both the anticontractile effect and membrane hyperpolarization of periadventitial fat were abolished by inhibition of delayed-rectifier K+ (K(v)) channels with 4-aminopyridine (2 mmol/L) or 3,4-diaminopyridine (1 mmol/L). Blocking other K+ channels with glibenclamide (3 micromol/L), apamin (1 micromol/L), iberiotoxin (100 nmol/L), tetraethylammonium ions (1 mmol/L), tetrapentylammonium ions (10 micromol/L), or Ba2+ (3 micromol/L) had no effect. Longitudinal removal of half the perivascular tissue reduced the anticontractile effect of fat by almost 50%, whereas removal of the endothelium had no effect. We suggest that visceral periadventitial adipose tissue controls mesenteric arterial tone by inducing vasorelaxation via K(v) channel activation in vascular smooth muscle cells. PMID:15302842

  2. Chronic hypoxia during gestation enhances uterine arterial myogenic tone via heightened oxidative stress.

    Directory of Open Access Journals (Sweden)

    Daliao Xiao

    Full Text Available Chronic hypoxia during gestation has profound adverse effects on the adaptation of uteroplacental circulation in pregnancy. Yet, the underlying mechanisms are not fully understood. The present study tested the hypothesis that enhanced production of reactive oxygen species (ROS in uterine arteries plays a critical role in the maladaptation of uterine circulation associated with chronic hypoxia. Uterine arteries were isolated from nonpregnant and near-term pregnant sheep maintained at sea level (~300 m or exposed to high-altitude (3801 m hypoxia for 110 days. Hypoxia significantly increased ROS production in uterine arteries of pregnant, but not nonpregnant, sheep. This was associated with a significant increase in NADPH oxidase (Nox 2, but not Nox1 or Nox4, protein abundance and total Nox activity in uterine arteries of pregnant animals. Chronic hypoxia significantly increased pressure-dependent uterine arterial myogenic tone in pregnant sheep, which was abrogated by a Nox inhibitor apocynin. Additionally, the hypoxia-induced increase in myogenic reactivity of uterine arteries to phorbol 12,13-dibutyrate in pregnant sheep was blocked by apocynin and tempol. In consistence with the myogenic responses, the hypoxia-mediated down-regulation of BKCa channel activity in uterine arteries of pregnant animals was reversed by apocynin. The findings suggest that heightened oxidative stress in uterine arteries plays a key role in suppressing the BKCa channel activity, resulting in increased myogenic reactivity and maladaptation of uteroplacental circulation caused by chronic hypoxia during gestation.

  3. PC-PLC/sphingomyelin synthase activity plays a central role in the development of myogenic tone in murine resistance arteries.

    Science.gov (United States)

    Mauban, Joseph R H; Zacharia, Joseph; Fairfax, Seth; Wier, Withrow Gil

    2015-06-15

    Myogenic tone is an intrinsic property of the vasculature that contributes to blood pressure control and tissue perfusion. Earlier investigations assigned a key role in myogenic tone to phospholipase C (PLC) and its products, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). Here, we used the PLC inhibitor, U-73122, and two other, specific inhibitors of PLC subtypes (PI-PLC and PC-PLC) to delineate the role of PLC in myogenic tone of pressurized murine mesenteric arteries. U-73122 inhibited depolarization-induced contractions (high external K(+) concentration), thus confirming reports of nonspecific actions of U-73122 and its limited utility for studies of myogenic tone. Edelfosine, a specific inhibitor of PI-PLC, did not affect depolarization-induced contractions but modulated myogenic tone. Because PI-PLC produces IP3, we investigated the effect of blocking IP3 receptor-mediated Ca(2+) release on myogenic tone. Incubation of arteries with xestospongin C did not affect tone, consistent with the virtual absence of Ca(2+) waves in arteries with myogenic tone. D-609, an inhibitor of PC-PLC and sphingomyelin synthase, strongly inhibited myogenic tone and had no effect on depolarization-induced contraction. D-609 appeared to act by lowering cytoplasmic Ca(2+) concentration to levels below those that activate contraction. Importantly, incubation of pressurized arteries with a membrane-permeable analog of DAG induced vasoconstriction. The results therefore mandate a reexamination of the signaling pathways activated by the Bayliss mechanism. Our results suggest that PI-PLC and IP3 are not required in maintaining myogenic tone, but DAG, produced by PC-PLC and/or SM synthase, is likely through multiple mechanisms to increase Ca(2+) entry and promote vasoconstriction.

  4. Regulation of vascular tone in rabbit ophthalmic artery: cross talk of endogenous and exogenous gas mediators.

    Science.gov (United States)

    Salomone, Salvatore; Foresti, Roberta; Villari, Ambra; Giurdanella, Giovanni; Drago, Filippo; Bucolo, Claudio

    2014-12-15

    Nitric oxide (NO), carbon monoxide (CO) and hydrogen sulphide (H2S) modulate vascular tone. In view of their therapeutic potential for ocular diseases, we examined the effect of exogenous CO and H2S on tone of isolated rabbit ophthalmic artery and their interaction with endogenous and exogenous NO. Ophthalmic artery segments mounted on a wire myograph were challenged with cumulative concentrations of phenylephrine (PE) in the presence or absence of NG-nitro-L-arginine (LNNA) to inhibit production of NO, the CO-releasing molecules CORMs or the H2S-donor GYY4137. The maximal vasoconstriction elicited by PE reached 20-30% of that induced by KCl but was dramatically increased by incubation with LNNA. GYY4137 significantly raised PE-mediated vasoconstriction, but it did not change the response to PE in the presence of LNNA or the relaxation to sodium nitroprusside (SNP). CORMs concentration-dependently inhibited PE-induced constriction, an effect that was synergistic with endogenous NO (reduced by LNNA), but insensitive to blockade of guanylyl cyclase by 1H-[1,2,4]oxadiazolo[4,3,-α]quinoxalin-1-one (ODQ). In vascular tissues cyclic GMP (cGMP) levels seemed reduced by GYY4137 (not significantly), but were not changed by CORM. These data indicate that CO is able per se to relax isolated ophthalmic artery and to synergize with NO, while H2S counteracts the effect of endogenous NO. CO does not stimulate cGMP production in our system, while H2S may reduce cGMP production stimulated by endogenous NO. These findings provide new insights into the complexities of gas interactions in the control of ophthalmic vascular tone, highlighting potential pharmacological targets for ocular diseases. PMID:25451691

  5. KCNQ Modulators Reveal a Key Role for KCNQ Potassium Channels in Regulating the Tone of Rat Pulmonary Artery Smooth Muscle

    OpenAIRE

    Joshi, Shreena; Sedivy, Vojtech; Hodyc, Daniel; Herget, Jan; Gurney, Alison M

    2009-01-01

    Potassium channels are central to the regulation of pulmonary vascular tone. The smooth muscle cells of pulmonary artery display a background K+ conductance with biophysical properties resembling those of KCNQ (KV7) potassium channels. Therefore, we investigated the expression and functional role of KCNQ channels in pulmonary artery. The effects of selective KCNQ channel modulators were investigated on K+ current and membrane potential in isolated pulmonary artery smoo...

  6. Closure of digital arteries in high vascular tone states as demonstrated by measurement of systolic blood pressure in the fingers

    DEFF Research Database (Denmark)

    Krähenbühl, B; Nielsen, S L; Lassen, N A

    1977-01-01

    Finger systolic blood pressure (FSP) was measured indirectly in normal subjects and patients with primary Raynaud phenomenon by applying a thin-walled plastic cuff around the finger and a strain gauge more distally to detect volume changes. Inducing a high vascular tone in one or more fingers...... also remained normal. In the high vascular tone state, a large transmural pressure difference must apparently be established before the digital arteries are forced open. The lowered opening pressure constitutes a manifestation of the closure phenomenon of the digital arteries described in patients...

  7. Fundamental role for the KCNE4 ancillary subunit in Kv7.4 regulation of arterial tone

    DEFF Research Database (Denmark)

    Jepps, Thomas A; Carr, Georgina; Lundegaard, Pia R;

    2015-01-01

    tone by Kv7 channels. In HEK cells expressing Kv7.4, co-expression of KCNE4 increased the membrane expression of Kv7.4 and significantly altered Kv7.4 current properties. Quantitative PCR analysis of different rat arteries found that the KCNE4 isoform predominated and proximity ligation experiments......), which coincided with impaired effects of Kv7 modulators. When KCNE4 expression was reduced, less Kv7.4 expression was found in the membrane of the mesenteric artery myocytes. These data show that KCNE4 is consistently expressed in a variety of arteries, and knockdown of the expression product leads...

  8. Role of Adenosine Receptor(s) in the Control of Vascular Tone in the Mouse Pudendal Artery.

    Science.gov (United States)

    Labazi, Hicham; Tilley, Stephen L; Ledent, Catherine; Mustafa, S Jamal

    2016-03-01

    Activation of adenosine receptors (ARs) has been implicated in the modulation of renal and cardiovascular systems, as well as erectile functions. Recent studies suggest that adenosine-mediated regulation of erectile function is mainly mediated through A2BAR activation. However, no studies have been conducted to determine the contribution of AR subtype in the regulation of the vascular tone of the pudendal artery (PA), the major artery supplying and controlling blood flow to the penis. Our aim was to characterize the contribution of AR subtypes and identify signaling mechanisms involved in adenosine-mediated vascular tone regulation in the PA. We used a DMT wire myograph for muscle tension measurements in isolated PAs from wild-type, A2AAR knockout, A2BAR knockout, and A2A/A2BAR double-knockout mice. Real-time reverse transcription-polymerase chain reaction was used to determine the expression of the AR subtypes. Data from our pharmacologic and genetic approaches suggest that AR activation-mediated vasodilation in the PA is mediated by both the A2AAR and A2BAR, whereas neither the A1AR nor A3AR play a role in vascular tone regulation of the PA. In addition, we showed that A2AAR- and A2BAR-mediated vasorelaxation requires activation of nitric oxide and potassium channels; however, only the A2AAR-mediated response requires protein kinase A activation. Our data are complemented by mRNA expression showing the expression of all AR subtypes with the exception of the A3AR. AR signaling in the PA may play an important role in mediating erection and represent a promising therapeutic option for the treatment of erectile dysfunction. PMID:26718241

  9. Role of T-type calcium channels in myogenic tone of skeletal muscle resistance arteries

    DEFF Research Database (Denmark)

    VanBavel, Ed; Sorop, Oana; Andreasen, Ditte;

    2002-01-01

    T-type calcium channels may be involved in the maintenance of myogenic tone. We tested their role in isolated rat cremaster arterioles obtained after CO(2) anesthesia and decapitation. Total RNA was analyzed by RT-PCR and Southern blotting for calcium channel expression. We observed expression...... of voltage-operated calcium (Ca(V)) channels Ca(V)3.1 (T-type), Ca(V)3.2 (T-type), and Ca(V)1.2 (L-type) in cremaster arterioles (n = 3 rats). Amplification products were observed only in the presence of reverse transcriptase and cDNA. Concentration-response curves of the relatively specific L-type blocker...... verapamil and the relatively specific T-type blockers mibefradil and nickel were made on cannulated vessels with either myogenic tone (75 mmHg) or a similar level of constriction induced by 30 mM K(+) at 35 mmHg. Mibefradil and nickel were, respectively, 162-fold and 300-fold more potent in inhibiting...

  10. Increased arterial vascular tone during the night in patients with essential hypertension

    DEFF Research Database (Denmark)

    Scholze, A; Burkert, A; Mardanzai, K;

    2007-01-01

    and normotensive control subjects. Vascular tone was continuously quantified by the reflective index obtained by non-invasive digital photoplethysmography and an algorithm for continuous, investigator-independent, automatic analysis of digital volume pulse. During the first half of the night, the reflective index...... was significantly higher in 31 patients with essential hypertension compared to 30 normotensive control subjects (30.0+/-0.2 vs 28.8+/-0.2; P=0.001). In patients with essential hypertension, the reflective index significantly increased from 30.0+/-0.2 in the first half (from 2301 to 0230) to 30.......7+/-0.2 in the second half (from 0231 to 0600) of the night (n=31; P=0.027). In normotensive control subjects the reflective index also significantly increased from 28.8+/-0.2 in the first half of the night to 30.2+/-0.2 in the second half of the night (n=30; P=0.001). An increase of the reflective index tone indicated...

  11. Effect of simvastatin on vascular tone in porcine coronary artery: Potential role of the mitochondria.

    Science.gov (United States)

    Almukhtar, H; Garle, M J; Smith, P A; Roberts, R E

    2016-08-15

    Statins induce acute vasorelaxation which may contribute to the overall benefits of statins in the treatment of cardiovascular disease. The mechanism underlying this relaxation is unknown. As statins have been shown to alter mitochondrial function, in this study we investigated the role of mitochondria in the relaxation to simvastatin. Relaxation of porcine coronary artery segments by statins was measured using isolated tissue baths. Mitochondrial activity was determined by measuring changes in rhodamine 123 fluorescence. Changes in intracellular calcium levels were determined in freshly isolated smooth muscle cells with Fluo-4 using standard epifluorescent imaging techniques. Simvastatin, but not pravastatin, produced a slow relaxation of the coronary artery, which was independent of the endothelium. The relaxation was attenuated by the mitochondrial complex I inhibitor rotenone (10μM) and the complex III inhibitor myxothiazol (10μM), or a combination of the two. The complex III inhibitor antimycin A (10μM) produced a similar time-dependent relaxation of the porcine coronary artery, which was attenuated by rotenone. Changes in rhodamine 123 fluorescence showed that simvastatin (10μM) depolarized the membrane potential of mitochondria in both isolated mitochondria and intact blood vessels. Simvastatin and antimycin A both inhibited calcium-induced contractions in isolated blood vessels and calcium influx in smooth muscle cells and this inhibition was prevented by rotenone. In conclusion, simvastatin produces an endothelium-independent relaxation of the porcine coronary artery which is dependent, in part, upon effects on the mitochondria. The effects on the mitochondria may lead to a reduction in calcium influx and hence relaxation of the blood vessel. PMID:27343404

  12. Chronic deficit in nitric oxide elicits oxidative stress and augments T-type calcium-channel contribution to vascular tone of rodent arteries and arterioles

    DEFF Research Database (Denmark)

    Howitt, Lauren; Kuo, Ivana Y; Ellis, Anthie;

    2013-01-01

    AIMS: As cardiovascular disease is characterized by reduced nitric oxide bioavailability, our aim was to determine the impact of this change on the mechanism underlying vascular tone of pressurized arteries in vitro and in vivo. METHODS AND RESULTS: We used pressurized cerebral and mesenteric......, by regulating the bioavailability of reactive oxygen species produced by NADPH oxidase. Our data provide evidence for a novel causal link between nitric oxide deficit, oxidative stress, and T-type calcium channel function....

  13. Age-dependent impact of CaV 3.2 T-type calcium channel deletion on myogenic tone and flow-mediated vasodilatation in small arteries

    DEFF Research Database (Denmark)

    Mikkelsen, Miriam F; Björling, Karl; Jensen, Lars Jørn

    2016-01-01

    , structural remodeling, and mRNA + protein expression in small mesenteric arteries from CaV 3.2 knock-out vs. wild-type mice at young vs. mature adult age. In young mice, only, deletion of CaV 3.2 led to enhanced myogenic response and ∼50 % reduction of flow-mediated vasodilatation. Ni(2+) had both CaV 3.......2-dependent and -independent effects. No changes in mRNA expression of several important K(+) and Ca(2+) channel genes were induced by CaV 3.2 knock-out. However, the expression of the other T-type channel isoform (CaV 3.1) was reduced at the mRNA and protein level in mature adult compared to young WT...... arteries. Our study shows important roles of the CaV 3.2 T-type calcium channels in myogenic tone and flow-mediated vasodilation that disappear with aging. Since increased arterial tone is a risk factor for cardiovascular disease we conclude that CaV 3.2 channels, by modulating pressure- and flow...

  14. Redox signaling via oxidative inactivation of PTEN modulates pressure-dependent myogenic tone in rat middle cerebral arteries.

    Directory of Open Access Journals (Sweden)

    Debebe Gebremedhin

    Full Text Available The present study examined the level of generation of reactive oxygen species (ROS and roles of inactivation of the phosphatase PTEN and the PI3K/Akt signaling pathway in response to an increase in intramural pressure-induced myogenic cerebral arterial constriction. Step increases in intraluminal pressure of cannulated cerebral arteries induced myogenic constriction and concomitant formation of superoxide (O2 (.- and its dismutation product hydrogen peroxide (H2O2 as determined by fluorescent HPLC analysis, microscopic analysis of intensity of dihydroethidium fluorescence and attenuation of pressure-induced myogenic constriction by pretreatment with the ROS scavenger 4,hydroxyl-2,2,6,6-tetramethylpiperidine1-oxyl (tempol or Mito-tempol or MitoQ in the presence or absence of PEG-catalase. An increase in intraluminal pressure induced oxidation of PTEN and activation of Akt. Pharmacological inhibition of endogenous PTEN activity potentiated pressure-dependent myogenic constriction and caused a reduction in NPo of a 238 pS arterial KCa channel current and an increase in [Ca(2+]i level in freshly isolated cerebral arterial muscle cells (CAMCs, responses that were attenuated by Inhibition of the PI3K/Akt pathway. These findings demonstrate an increase in intraluminal pressure induced increase in ROS production triggered redox-sensitive signaling mechanism emanating from the cross-talk between oxidative inactivation of PTEN and activation of the PI3K/Akt signaling pathway that involves in the regulation of pressure-dependent myogenic cerebral arterial constriction.

  15. Two Tones

    DEFF Research Database (Denmark)

    Palludan, Charlotte

    2007-01-01

    This article examines how kindergarten-children are differentiated and segregated through vocal practices and processes. The analysis is based on empirical data, which originate from a long ethnographic fieldwork in Denmark. The author presents two different language tones: "a teaching tone...

  16. Contour Tones.

    Science.gov (United States)

    Yip, Moira

    1989-01-01

    Argues that contour tones in East Asian languages behave as melodic units consisting of a root node [upper] dominating a branching specification. It is also argued that, with upper as the tonal root node, no more than two rising or falling tones will contrast underlying. (49 references) (JL)

  17. Peripheral Arterial Tonometry to Measure the Effects of Vardenafil on Sympathetic Tone in Men with Lifelong Premature Ejaculation

    OpenAIRE

    Davide Francomano; Donini, Lorenzo M.; Andrea Lenzi; Antonio Aversa

    2013-01-01

    To elucidate whether adrenergic overtone is involved in the pathophysiology of men with lifelong (LL) premature ejaculation (PE), we investigated differences in reactive hyperemia index (RHI) responses by using peripheral arterial tonometry (PAT). 20 men with LL-PE (18–40 years) were enrolled in an 8-week, double-blind, placebo-controlled, crossover study and compared with 10 age-matched controls without LL-PE. Primary endpoints were PAT modifications induced by vardenafil 10 mg on demand. Se...

  18. Drug-Free Correction of the Tone of the Autonomic Nervous System in the Management of Cardiac Arrhythmia in Coronary Artery Disease

    Directory of Open Access Journals (Sweden)

    Sergey V. Popov, PhD, ScD

    2013-06-01

    Full Text Available Background: The aim of our study was to examine the possibility of ventricular extrasystole (VES management in CAD (coronary artery disease patients by attenuating the sympathetic activity with a course of electrical stimulation of the vagus nerve. Methods: A decrease in sympathetic tone was achieved via vagus nerve electrical stimulation (VNES. VNES was performed in 48 male CAD patients, mean age 53.5±4.1 years. Antiarrhythmic drug therapy was canceled prior to VNES therapy. The effect of VNES on heart rate variability (HRV and VES were carefully studied. All the patients received a 24-hour ECG monitoring. HRV was calculated for high frequency (HF and low frequency (LF bands and the LF/HF index was determined. Results: Immediately following VNES therapy, 30 patients (group 1 reported alleviation of angina signs and the LF/HF index was significantly decreased (p=0.001. Eighteen patients (group 2 showed no change either in health or the LF/HF index. According to ECG and echocardiography, the VES number did not significantly change immediately after VNES therapy. One month after the VNES course, group 1 reported further improvement in health; the LF/HF index approached normal values. In group 2, the LF/HF significantly decreased (p=0.043. However, in the entire study sample, the VES number significantly decreased overall (p=0.025. Conclusion: VNES attenuated the cardiac effects of hypersympathicotonia decreased the ischemic impact on the myocardium, alleviated the cardiac angina signs, and beneficially influenced the VES number in CAD patients.

  19. 不同浓度依托咪酯对内毒素孵育前后兔离体肺、体动脉环张力的影响%Effect of different concentrations of etomidate on the tone of isolated rabbit pulmonary and aortic artery rings before and after LPS incubation

    Institute of Scientific and Technical Information of China (English)

    李玢琳; 张锦; 李娜; 佟冬怡

    2012-01-01

    Objective To observe the effects of etomidate on isolated rabbit pulmonary and aortic artery rings before and after LPS incubation, and provide evidence for narcotic choice of clinic septic shock. Methods The rings of pulmonary and aortic arteries were prepared and randomly divided into 4 groups: normal pulmonary artery rings group, LPS incubated pulmonary artery rings group, normal aortic artery rings group and LPS incubated aortic artery rings group. The effects of etomidate of 1. 0 μmol/L,2. 0 μmol/L, 10. 0 μmol/L on pulmonary and aortic arteries in two groups were observed when phenylephrine( PE )pre-contracting. Results The tone of pulmonary and aortic arteries be fore and after LPS incubated had no significant difference( P > 0. 05 )when 1. 0 μmol/L of etomidate was given; the tone of normal pulmonary and aortic arteries and LPS aortic arteries increased significantly( P 0.05);2.0 μmol/L时,正常肺、主动脉环和LPS孵育后主动脉环张力明显上升(P<0.05);10.0 μmol/L时,LPS孵育的肺、主动脉环的张力较正常肺、主动脉环明显下降(P<0.05).结论 低浓度Eto收缩机制占主导,但随着浓度增加,Eto引起内毒素孵育后肺动脉舒张的程度比体动脉更明显,可能与高浓度Eto抑制血管收缩功能有关.

  20. Automated tone transcription

    CERN Document Server

    Bird, S

    1994-01-01

    In this paper I report on an investigation into the problem of assigning tones to pitch contours. The proposed model is intended to serve as a tool for phonologists working on instrumentally obtained pitch data from tone languages. Motivation and exemplification for the model is provided by data taken from my fieldwork on Bamileke Dschang (Cameroon). Following recent work by Liberman and others, I provide a parametrised F_0 prediction function P which generates F_0 values from a tone sequence, and I explore the asymptotic behaviour of downstep. Next, I observe that transcribing a sequence X of pitch (i.e. F_0) values amounts to finding a tone sequence T such that P(T) {}~= X. This is a combinatorial optimisation problem, for which two non-deterministic search techniques are provided: a genetic algorithm and a simulated annealing algorithm. Finally, two implementations---one for each technique---are described and then compared using both artificial and real data for sequences of up to 20 tones. These programs ...

  1. Effet placebo, effet nocebo: comment la science explique les guérions miraculeuses

    OpenAIRE

    Quertemont, Etienne

    2002-01-01

    L’effet placebo est habituellement considéré comme l’ensemble des réponses psychologiques et physiologiques des patients à une substance inerte. On parle d’effet placebo lorsque cette réponse constitue un effet bénéfique pour la santé et d’effet nocebo lorsque les conséquences sont néfastes. Cependant, les phénomènes placebo/nocebo recouvrent plus largement tous les effets du contexte environnemental qui ne résultent pas spécifiquement du traitement médical administré. Une partie de ce qu’on ...

  2. Change of tone

    CERN Multimedia

    Association du personnel

    2006-01-01

    The President of the Staff Association set the tone by leaving the members of the SCC speechless when he read out a solemn declaration For a start, Management invites us to discuss the Five-Yearly Review without having provided any formal text. Concertation Method of analysis and use of data previously adopted by Council. Salaries. Increase. Employment conditions. Family allowances. Crèche. Career perspectives. Referendum.

  3. Dynamic resistance training decreases sympathetic tone in hypertensive ovariectomized rats

    Energy Technology Data Exchange (ETDEWEB)

    Shimojo, G.L.; Palma, R.K.; Brito, J.O.; Sanches, I.C. [Laboratório de Fisiologia Translacional, Programa de Ciências da Reabilitação, Universidade Nove de Julho, São Paulo, SP (Brazil); Irigoyen, M.C. [Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); De Angelis, K. [Laboratório de Fisiologia Translacional, Programa de Ciências da Reabilitação, Universidade Nove de Julho, São Paulo, SP (Brazil)

    2015-03-27

    The aim of this study was to investigate the effects of resistance exercise training on hemodynamics and cardiac autonomic control in ovariectomized spontaneously hypertensive rats. Female rats were divided into 4 groups: sedentary control (SC), sedentary hypertensive (SH), sedentary hypertensive ovariectomized (SHO), and resistance-trained hypertensive ovariectomized (RTHO). Resistance exercise training was performed on a vertical ladder (5 days/week, 8 weeks) at 40-60% maximal load. Direct arterial pressure was recorded. Vagal and sympathetic tones were measured by heart rate (HR) responses to methylatropine (3 mg/kg, iv) and propranolol (4 mg/kg, iv). Ovariectomy resulted in additional increases in blood pressure in hypertensive rats and was associated with decreased vagal tone. Resistance exercise trained rats had lower mean arterial pressure than untrained rats (RTHO: 159±2.2 vs SHO: 177±3.4 mmHg), as well as resting bradycardia (RTHO: 332±9.0 vs SHO: 356±5 bpm). Sympathetic tone was also lower in the trained group. Moreover, sympathetic tone was positively correlated with resting HR (r=0.7, P<0.05). The additional arterial pressure increase in hypertensive rats caused by ovarian hormone deprivation was attenuated by moderate-intensity dynamic resistance training. This benefit may be associated with resting bradycardia and reduced cardiac sympathetic tone after training, which suggests potential benefits of resistance exercise for the management of hypertension after ovarian hormone deprivation.

  4. Dynamic resistance training decreases sympathetic tone in hypertensive ovariectomized rats

    Directory of Open Access Journals (Sweden)

    G.L. Shimojo

    2015-06-01

    Full Text Available The aim of this study was to investigate the effects of resistance exercise training on hemodynamics and cardiac autonomic control in ovariectomized spontaneously hypertensive rats. Female rats were divided into 4 groups: sedentary control (SC, sedentary hypertensive (SH, sedentary hypertensive ovariectomized (SHO, and resistance-trained hypertensive ovariectomized (RTHO. Resistance exercise training was performed on a vertical ladder (5 days/week, 8 weeks at 40-60% maximal load. Direct arterial pressure was recorded. Vagal and sympathetic tones were measured by heart rate (HR responses to methylatropine (3 mg/kg, iv and propranolol (4 mg/kg, iv. Ovariectomy resulted in additional increases in blood pressure in hypertensive rats and was associated with decreased vagal tone. Resistance exercise trained rats had lower mean arterial pressure than untrained rats (RTHO: 159±2.2 vs SHO: 177±3.4 mmHg, as well as resting bradycardia (RTHO: 332±9.0 vs SHO: 356±5 bpm. Sympathetic tone was also lower in the trained group. Moreover, sympathetic tone was positively correlated with resting HR (r=0.7, P<0.05. The additional arterial pressure increase in hypertensive rats caused by ovarian hormone deprivation was attenuated by moderate-intensity dynamic resistance training. This benefit may be associated with resting bradycardia and reduced cardiac sympathetic tone after training, which suggests potential benefits of resistance exercise for the management of hypertension after ovarian hormone deprivation.

  5. [Vasomotor tone and CBP : monitoring components, pratical and therapeutic approaches].

    Science.gov (United States)

    Isetta, C; Janot, N

    2012-05-01

    The vasomotor tone is an essential determinant of blood pressure. Vascular resistance is the result of a calculation including vasomotor tone, blood flow and blood viscosity. The vascular tone is modulated by the sympathetic system and the direct actions of drugs (patient's pathology, anaesthesia). The pressure and flow allow the vascular tone apprehension. A decrease in vasomotor tone lowers the mean arterial pressure and may cause an intense vasoplegia with arterial vascular resistance below than 800 dyn/s/cm(5) leading to a lack of tissue oxygenation. Vasomotor paralysis can be caused by the patient medications or an intense inflammatory reaction starting at the extracorporeal circulation onset. Monitoring parameters of extracorporeal circulation such as pressure, flow, arterial and venous oxygen saturation, blood level in the venous reservoir, and extensively blood gases, haemoglobin, CO(2) partial pressure level of the oxygenator vent, bispectral index, and oxygen saturation of cerebral tissue are reviewed. They will know the vasoplegia consequences and bear an indication of adequate tissue oxygenation. It may be obtained by using vasopressors (ephedrine, norepinephrine, terbutalin and vasopressin) methylene blue, increasing blood viscosity (erythrocytes) and blood flow, even by inducing hypothermia.

  6. Dynamic resistance training decreases sympathetic tone in hypertensive ovariectomized rats

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the effects of resistance exercise training on hemodynamics and cardiac autonomic control in ovariectomized spontaneously hypertensive rats. Female rats were divided into 4 groups: sedentary control (SC), sedentary hypertensive (SH), sedentary hypertensive ovariectomized (SHO), and resistance-trained hypertensive ovariectomized (RTHO). Resistance exercise training was performed on a vertical ladder (5 days/week, 8 weeks) at 40-60% maximal load. Direct arterial pressure was recorded. Vagal and sympathetic tones were measured by heart rate (HR) responses to methylatropine (3 mg/kg, iv) and propranolol (4 mg/kg, iv). Ovariectomy resulted in additional increases in blood pressure in hypertensive rats and was associated with decreased vagal tone. Resistance exercise trained rats had lower mean arterial pressure than untrained rats (RTHO: 159±2.2 vs SHO: 177±3.4 mmHg), as well as resting bradycardia (RTHO: 332±9.0 vs SHO: 356±5 bpm). Sympathetic tone was also lower in the trained group. Moreover, sympathetic tone was positively correlated with resting HR (r=0.7, P<0.05). The additional arterial pressure increase in hypertensive rats caused by ovarian hormone deprivation was attenuated by moderate-intensity dynamic resistance training. This benefit may be associated with resting bradycardia and reduced cardiac sympathetic tone after training, which suggests potential benefits of resistance exercise for the management of hypertension after ovarian hormone deprivation

  7. Oxidative Stress in Hypobaric Hypoxia and Influence on Vessel-Tone Modifying Mediators

    OpenAIRE

    Pichler Hefti, Jacqueline Renée; Sonntag, Denise; Hefti, Urs; Risch, Lorenz; Schoch, Otto D; Turk, Alexander J; Hess, Thomas; Bloch, Konrad E; Maggiorini,Marco; Merz, Tobias Michael; Weinberger, Klaus M.; Huber, Andreas R

    2013-01-01

    Increased pulmonary artery pressure is a well-known phenomenon of hypoxia and is seen in patients with chronic pulmonary diseases, and also in mountaineers on high altitude expedition. Different mediators are known to regulate pulmonary artery vessel tone. However, exact mechanisms are not fully understood and a multimodal process consisting of a whole panel of mediators is supposed to cause pulmonary artery vasoconstriction. We hypothesized that increased hypoxemia is associated with an ...

  8. Oxidative stress in hypobaric hypoxia and influence on vessel-tone modifying mediators

    OpenAIRE

    Pichler Hefti, Jacqueline; Sonntag, Denise; Hefti, Urs; Risch, Lorenz; Schoch, Otto D; Turk, Alexander J; Hess, Thomas; Bloch, Konrad E; Maggiorini,Marco; Merz, Tobias M; Weinberger, Klaus M.; Huber, Andreas R

    2013-01-01

    Increased pulmonary artery pressure is a well-known phenomenon of hypoxia and is seen in patients with chronic pulmonary diseases, and also in mountaineers on high altitude expedition. Different mediators are known to regulate pulmonary artery vessel tone. However, exact mechanisms are not fully understood and a multimodal process consisting of a whole panel of mediators is supposed to cause pulmonary artery vasoconstriction. We hypothesized that increased hypoxemia is associated with an incr...

  9. The effect of small dose propofol on the tone of rabbit pulmonary artery and chest aorta after LPS induction%小剂量异丙酚对内毒素孵育兔肺动脉及体动脉血管的影响

    Institute of Scientific and Technical Information of China (English)

    来源; 张锦

    2015-01-01

    目的:观察小剂量异丙酚(Propofol,PF)对内毒素(LPS)致感染性休克兔外周血管阻力(SVR)、阻力指数(SVRI)、胸腔液体量(TFC)以及离体肺动脉环和胸主动脉环张力的影响。研究小剂量异丙酚对感染性休克兔的保护作用及可能机制。方法选择健康成年雄性大耳兔20只,体重2.5~2.8kg,随机分为正常组(N组)和LPS 致休克模型组(L组),再以两种不同小剂量(50μmol/L和100μmol/L)异丙酚对两组分别进行干预,每项干预5只。用胸电生物阻抗法血液动力学连续监护系统(Bioz)测量各组SVR、SVRI和TFC,之后制备离体肺动脉环和主动脉环,连接张力换能器,观察各组血管环张力的变化。结果干预前与N组相比,L组SVR、SVRI下降,TFC升高(P<0.05),肺动脉环张力有所下降,但不如主动脉环张力下降明显(P<0.05)。与干预前相比,L组SVR、SVRI均有所升高(P<0.05),100μmol/L剂量下同时还伴有TFC下降(P<0.05)。离体条件下50μmol/L剂量时仅增加主动脉环对PE的反应性(P<0.05),100μmol/L剂量下在增加主动脉张力的同时,还能降低肺动脉张力,使肺动脉与主动脉环张力比值(P/A 值)降低(P<0.05)。结论小剂量异丙酚(50μmol/L 和100μmol/L)通过直接作用于血管壁调节血管张力,增加感染性休克兔主动脉血管张力,维持体循环稳定。其中100μmol/L的PF不但增加主动脉张力,还能降低肺动脉张力,更能有效纠正血管舒缩状态,改善组织灌注,对感染性休克兔的血管具有保护作用。%Objective To observe the effect of propofol (PF) in small dose on the tone of alive rabbit systemic vascular resistance/index (SVR/SVRI),thoracic fluid content (TFC) and isolated rabbit pulmonary artery and chest aorta rings before and after LPS (lipopolysaccharide) incubation, approach the protection function and possible

  10. Increased sympathetic tone in forearm subcutaneous tissue in primary hypothyroidism

    DEFF Research Database (Denmark)

    Vagn Nielsen, H; Hasselström, K; Feldt-Rasmussen, U;

    1987-01-01

    Sympathetic reflex regulation of subcutaneous blood flow (SBF) in the forearm was studied in eight patients with primary hypothyroidism. Diastolic arterial pressure was greater than or equal to 95 mmHg in five patients. SBF was determined by local clearance of Na99mTcO4. Sympathetic vasoconstrict......Sympathetic reflex regulation of subcutaneous blood flow (SBF) in the forearm was studied in eight patients with primary hypothyroidism. Diastolic arterial pressure was greater than or equal to 95 mmHg in five patients. SBF was determined by local clearance of Na99mTcO4. Sympathetic.......02)). In conclusion sympathetic vasoconstrictor activity in adipose tissue is markedly increased in primary hypothyroidism. Sympathetic tone and arterial pressure are reduced during treatment....

  11. Root Tone: A Holistic Approach to Tone Pedagogy of Western Classical Flute

    Science.gov (United States)

    BastaniNezhad, Arya

    2012-01-01

    This article examines how key components of holistic tone production can help flutists form a resonant tone. This is framed in an exploration of tone pedagogy and includes a model of tone evaluation and education. This research is also applicable to other instrumentalists, especially wind players. In this case study information was collected by…

  12. Designing Tone Reservation PAR Reduction

    Directory of Open Access Journals (Sweden)

    Johansson Albin

    2006-01-01

    Full Text Available Tone reservation peak-to-average (PAR ratio reduction is an established area when it comes to bringing down signal peaks in multicarrier (DMT or OFDM systems. When designing such a system, some questions often arise about PAR reduction. Is it worth the effort? How much can it give? How much does it give depending on the parameter choices? With this paper, we attempt to answer these questions without resolving to extensive simulations for every system and every parameter choice. From a specification of the allowed spectrum, for instance prescribed by a standard, including a PSD-mask and a number of tones, we analytically predict achievable PAR levels, and thus implicitly suggest parameter choices. We use the ADSL2 and ADSL2+ systems as design examples.

  13. Multi-toning Image Adjustment

    Institute of Scientific and Technical Information of China (English)

    LIU Shi-guang; WANG Xiao-juan; PENG Qun-sheng

    2011-01-01

    Due to the different lighting environments or other reasons, the pixel colors may be quite different in one image which causes distinct visual discontinuities. It makes the analysis and processing of such an image more difficult and sometime impossible. In this paper, a unified multi-toning image adjustment method is proposed to solve this problem. First, a novel unsupervised clustering method was proposed to partition the source and the target image into a certain number of subsets with similar color statistics. By matching the texture characteristics and luminance distribution between the blocks, it can create optimized correspondence. Then, the color information was transferred from the matched pixels in the source blocks to the target ones. Graph cut method was used to optimize the seams between different subsets in the final step. This method can automatically perform color adjustment of a multi-toning image. It is simple and efficient. Various results show the validity of this method.

  14. Regulation of vascular tone by adipocytes

    Directory of Open Access Journals (Sweden)

    Van de Voorde Johan

    2011-03-01

    Full Text Available Abstract Recent studies have shown that adipose tissue is an active endocrine and paracrine organ secreting several mediators called adipokines. Adipokines include hormones, inflammatory cytokines and other proteins. In obesity, adipose tissue becomes dysfunctional, resulting in an overproduction of proinflammatory adipokines and a lower production of anti-inflammatory adipokines. The pathological accumulation of dysfunctional adipose tissue that characterizes obesity is a major risk factor for many other diseases, including type 2 diabetes, cardiovascular disease and hypertension. Multiple physiological roles have been assigned to adipokines, including the regulation of vascular tone. For example, the unidentified adipocyte-derived relaxing factor (ADRF released from adipose tissue has been shown to relax arteries. Besides ADRF, other adipokines such as adiponectin, omentin and visfatin are vasorelaxants. On the other hand, angiotensin II and resistin are vasoconstrictors released by adipocytes. Reactive oxygen species, leptin, tumour necrosis factor α, interleukin-6 and apelin share both vasorelaxing and constricting properties. Dysregulated synthesis of the vasoactive and proinflammatory adipokines may underlie the compromised vascular reactivity in obesity and obesity-related disorders.

  15. The effect of neuropeptides on vessel tone and cAMP production

    DEFF Research Database (Denmark)

    Yao, W; Sheikh, S P; Ottesen, B;

    1996-01-01

    The effect of VIP, PHM, PHV, PACAP-27, and PACAP-38 on vessel tone and cAMP production was investigated in rabbit ovarian arteries in vitro. The peptides (10(-7)M) induced a significant relaxation on NA-precontracted vessels and displayed similar potencies. The cAMP accumulation induced by PACAP-...

  16. Setting the Tone for 2008

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The government will focus on curbing inflation and preventing the economy from overheating The Central Economic Work Conference was held in Beijing on December 3-5,setting the tone for China’s economic development in 2008. Just say no:inflation and overheating Senior economist Zhang Yongjun with State Information Center stated the primary tasks next year would be two"preventions": preventing the already fast economic growth from becoming overheated,and pre- venting the price increases from creating real inflation.

  17. Effets du fluor et du phosphogypse chez les organismes marins

    OpenAIRE

    Martin, J. L.; Le Guellec, Anne-marie; Cosson, R

    1982-01-01

    Dans le cadre général des recherches visant à déterminer l'action des effluents industriels et plus précisément du fluor dans le cas de cette étude, le programme dont les résultats sont présentés avait pour but de déterminer les effets de cet élément sur les organismes marins. Trois aspects essentiels ont été envisagés : - Effets létaux du fluor ; - effets du fluor sur certaines fonctions éthologiques ; - bio-accumulation de l'élément par les organismes marins.

  18. Adaptation of active tone in the mouse descending thoracic aorta under acute changes in loading.

    Science.gov (United States)

    Murtada, S-I; Lewin, S; Arner, A; Humphrey, J D

    2016-06-01

    Arteries can adapt to sustained changes in blood pressure and flow, and it is thought that these adaptive processes often begin with an altered smooth muscle cell activity that precedes any detectable changes in the passive wall components. Yet, due to the intrinsic coupling between the active and passive properties of the arterial wall, it has been difficult to delineate the adaptive contributions of active smooth muscle. To address this need, we used a novel experimental-computational approach to quantify adaptive functions of active smooth muscle in arterial rings excised from the proximal descending thoracic aorta of mice and subjected to short-term sustained circumferential stretches while stimulated with various agonists. A new mathematical model of the adaptive processes was derived and fit to data to describe and predict the effects of active tone adaptation. It was found that active tone was maintained when the artery was adapted close to the optimal stretch for maximal active force production, but it was reduced when adapted below the optimal stretch; there was no significant change in passive behavior in either case. Such active adaptations occurred only upon smooth muscle stimulation with phenylephrine, however, not stimulation with KCl or angiotensin II. Numerical simulations using the proposed model suggested further that active tone adaptation in vascular smooth muscle could play a stabilizing role for wall stress in large elastic arteries.

  19. Influence of String Stiffness on Piano Tone

    CERN Document Server

    Nie, Lai-Mei

    2010-01-01

    Piano tones vary according to how pianist touches the keys. Many possible factors contribute to the relations between piano touch and tone. Focusing on the stiffness of string, we establish a model for vibration of a real piano string and derive a semi-analytical solution to the vibration equation.

  20. CONSTRUCTION SENSITIVITY IN PINGYAO TONE SANDHI

    Directory of Open Access Journals (Sweden)

    Hui-shan Lin

    2012-06-01

    Full Text Available This paper investigates tone sandhi phenomena in Pingyao, a Jin dialect spoken in Shanxi province in China. Pingyao tone sandhi is special in that tone sandhi in bi-syllabic strings is construction sensitive, but tone sandhi in tri-syllabic strings is not fully conditioned by construction types. Based on Optimality Theory (OT, this paper proposes analyses for bi-tonal and tri-tonal sandhi in Pingyao. We show that while bi-tonal sandhi can be accounted for by assuming that there are different grammars associated with different construction types, the lack of construction sensitivity in certain tri-syllabic strings suggests that the association between construction types and phonological grammars can be sacrificed to comply with a higher demand. In Pingyao, the higher demand is to avoid having a tri-tonal string with marked tone sandhi domain from being associated with conflicting grammars.

  1. Perception and production of tone in aphasia.

    Science.gov (United States)

    Gandour, J; Petty, S H; Dardarananda, R

    1988-11-01

    An acoustical and perceptual study of lexical tone was conducted to evaluate the extent and nature of tonal disruption in aphasia. The language under investigation was Thai, a tone language which has five lexical tones--mid, low, falling, high, and rising. Subjects included six left brain-damaged aphasics (two Broca's, one transcortical motor, one global, one conduction, one Wernicke), one right brain-damaged nonaphasic, one cerebellar dysarthric, and five normals. High-quality tape recordings of each subject's productions of a minimal set of five, monosyllabic Thai words were presented to 10 adult Thai listeners for identification. Results from the phonemic identification tests indicated that tone production is relatively spared in aphasic patients with unilateral left hemisphere lesions. The performance of the global aphasic, however, was considerably below normal. Patterns of tonal confusions further revealed that the performance of all aphasics, except the global, differed from that of normal speakers primarily in degree rather than in kind. Tonal contrasts were signaled at a high level of proficiency by the right brain-damaged and dysarthric patients. Acoustical analysis revealed that F0 contours associated with the five tones for all aphasics, except the global, were similar in overall shape as well as position in the tone space to those of normals. F0 contours for the right brain-damaged patient and the dysarthric also generally agreed with those of normals in terms of shape and position. F0 ranges of both aphasic and nonaphasic brain-damaged speakers were generally larger than those of normals for all five tones. The relationship between tone and vowel duration was generally similar to that of normals for all brain-damaged speakers. A comparison of aphasics' performance on tone perception (J. Gandour & R. Dardarananda, 1983, Brain and Language, 18, 94-114) and tone production indicated that, for the normal and right brain-damaged subjects, performance on

  2. Tone and prosodic organization in Cherokee nouns

    Science.gov (United States)

    Johnson, Keith; Haag, Marcia

    2005-04-01

    Preliminary observations in the speech of one speaker of Cherokee led us to postulate three factors affecting tone in Cherokee. (1) Tone may be lexically specified with distinctive low, low fall, low rise, and high tones. (2) There is a metrically determined high fall pattern which may be distributed over not more than 2 syllables from the right edge of a prosodic domain. (3) Intonational domains may be associated with discourse functions, marked by high fall, or by pitch range upstep. This paper tests these observations in recordings of word lists and sentences produced by five additional speakers. The analysis we give, positing both lexical tone and metrical prosodic accent, is not unique in descriptions of language, but is different from the usual description of Cherokee. [Work supported by NSF.

  3. Etude des effets du martelage repetitif sur les contraintes residuelles

    Science.gov (United States)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  4. General perceptual contributions to lexical tone normalization.

    Science.gov (United States)

    Huang, Jingyuan; Holt, Lori L

    2009-06-01

    Within tone languages that use pitch variations to contrast meaning, large variability exists in the pitches produced by different speakers. Context-dependent perception may help to resolve this perceptual challenge. However, whether speakers rely on context in contour tone perception is unclear; previous studies have produced inconsistent results. The present study aimed to provide an unambiguous test of the effect of context on contour lexical tone perception and to explore its underlying mechanisms. In three experiments, Mandarin listeners' perception of Mandarin first and second (high-level and mid-rising) tones was investigated with preceding speech and non-speech contexts. Results indicate that the mean fundamental frequency (f0) of a preceding sentence affects perception of contour lexical tones and the effect is contrastive. Following a sentence with a higher-frequency mean f0, the following syllable is more likely to be perceived as a lower frequency lexical tone and vice versa. Moreover, non-speech precursors modeling the mean spectrum of f0 also elicit this effect, suggesting general perceptual processing rather than articulatory-based or speaker-identity-driven mechanisms. PMID:19507980

  5. Estimation of cerebral vascular tone during exercise; evaluation by critical closing pressure in humans

    DEFF Research Database (Denmark)

    Ogoh, Shigehiko; Brothers, R Matthew; Jeschke, Monica;

    2010-01-01

    The aim of the present study was to calculate critical closing pressure (CCP) of the cerebral vasculature at rest and during exercise to estimate cerebral vascular tone. Five men and two women were seated upright for 15 min and then performed 15 min of right-legged knee extension exercise at 40, 60...... and 75% of their maximal workload (WL(max)). Middle cerebral artery blood velocity (MCA V) and blood pressure in the radial artery were recorded. The CCP was calculated by linear extrapolation from 1 min recordings of pairs of systolic and diastolic pressure and MCA V waveforms from both the right...

  6. Computational Support for Early Elicitation and Classification of Tone

    Science.gov (United States)

    Bird, Steven; Lee, Haejoong

    2014-01-01

    Investigating a tone language involves careful transcription of tone on words and phrases. This is challenging when the phonological categories--the tones or melodies--have not been identified. Effects such as coarticulation, sandhi, and phrase-level prosody appear as obstacles to early elicitation and classification of tone. This article presents…

  7. Contrastive Analysis of Intonation and Tone in Chinese and English

    Institute of Scientific and Technical Information of China (English)

    甘田

    2014-01-01

    In English, intonation is the main research object of supra-segmental phonology, it refers to the changes of tone and pitch. English intonation is non-tone language which means the word meaning will not changed with the changing of the inde-pendent word’s tone, while Chinese is Tone language, in which tone often determinates the meaning of word, different tones are representative of different meanings. Chinese language function exerts differently in tone and intonation , and it is a bit com-plicated compared with English.

  8. Arterial endothelial function measurement method and apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Maltz, Jonathan S; Budinger, Thomas F

    2014-03-04

    A "relaxoscope" (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxation. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.

  9. Perception of tones by infants learning a non-tone language

    NARCIS (Netherlands)

    Kager, René; Liu, Liquan

    2014-01-01

    This article examines the perception of tones by non-tone-language-learning (non-tonelearning) infants between 5 and 18 months in a study that reveals infants’ initial sensitivity to tonal contrasts, deterioration yet plasticity of tonal sensitivity at the end of the first year, and a perceptual reb

  10. Beating frequency and amplitude modulation of the piano tone due to coupling of tones

    Science.gov (United States)

    Cartling, Bo

    2005-04-01

    The influence on a piano tone from weak coexcitation of damped adjacent tones due to coupling via the bridge is studied. The frequency and amplitude modulation of the sound resulting from coexcitation of one strong and one or two weak tones is analyzed. One weak tone causes frequency and amplitude modulation of the sound, and two weak tones produce beating frequency and amplitude modulation, where the beatings of the two modulations are of opposite phase. By digital recording of the sound of piano tones, the appearance of these phenomena is verified. The audibility of the observed frequency and amplitude modulation is discussed in terms of previously determined detection thresholds. The beating character of both frequency and amplitude modulations, however, distinguishes the phenomena from those previously studied and prompts further psychoacoustic investigations. It is shown that detuning of unison strings may significantly increase the frequency deviation of the frequency modulation in conjunction with affected amplitude modulation. The modulatory effects of coupling to adjacent tones therefore may possibly be utilized in the tuning process. A coupling of tones analogous to the situation in a piano may arise in other stringed musical instruments transferring string vibrations to a soundboard via a bridge. .

  11. Direct Numerical Simulation of Automobile Cavity Tones

    Science.gov (United States)

    Kurbatskii, Konstantin; Tam, Christopher K. W.

    2000-01-01

    The Navier Stokes equation is solved computationally by the Dispersion-Relation-Preserving (DRP) scheme for the flow and acoustic fields associated with a laminar boundary layer flow over an automobile door cavity. In this work, the flow Reynolds number is restricted to R(sub delta*) < 3400; the range of Reynolds number for which laminar flow may be maintained. This investigation focuses on two aspects of the problem, namely, the effect of boundary layer thickness on the cavity tone frequency and intensity and the effect of the size of the computation domain on the accuracy of the numerical simulation. It is found that the tone frequency decreases with an increase in boundary layer thickness. When the boundary layer is thicker than a certain critical value, depending on the flow speed, no tone is emitted by the cavity. Computationally, solutions of aeroacoustics problems are known to be sensitive to the size of the computation domain. Numerical experiments indicate that the use of a small domain could result in normal mode type acoustic oscillations in the entire computation domain leading to an increase in tone frequency and intensity. When the computation domain is expanded so that the boundaries are at least one wavelength away from the noise source, the computed tone frequency and intensity are found to be computation domain size independent.

  12. Caliber-Persistent Artery

    Directory of Open Access Journals (Sweden)

    Sabrina Araújo Pinho Costa

    2015-01-01

    Full Text Available Caliber-persistent artery (CPLA of the lip is a common vascular anomaly in which a main arterial branch extends to the surface of the mucous tissue with no reduction in its diameter. It usually manifests as pulsatile papule, is easily misdiagnosed, and is observed more frequently among older people, suggesting that its development may involve a degenerative process associated with aging; CPLA is also characterized by the loss of tone of the adjacent supporting connective tissue. Although the diagnosis is clinical, high-resolution Doppler ultrasound is a useful noninvasive tool for evaluating the lesion. This report describes the case of a 58-year-old male patient who complained of a lesion of the lower lip with bleeding and recurrent ulceration. The patient was successfully treated in our hospital after a diagnosis of CPLA and is currently undergoing a clinical outpatient follow-up with no complaints.

  13. Collaborative Documentation and Revitalization of Cherokee Tone

    Science.gov (United States)

    Herrick, Dylan; Berardo, Marcellino; Feeling, Durbin; Hirata-Edds, Tracy; Peter, Lizette

    2015-01-01

    Cherokee, the sole member of the southern branch of Iroquoian languages, is a severely endangered language. Unlike other members of the Iroquoian family, Cherokee has lexical tone. Community members are concerned about the potential loss of their language, and both speakers and teachers comment on the difficulty that language learners have with…

  14. Local adaptive tone mapping for video enhancement

    Science.gov (United States)

    Lachine, Vladimir; Dai, Min (.

    2015-03-01

    As new technologies like High Dynamic Range cameras, AMOLED and high resolution displays emerge on consumer electronics market, it becomes very important to deliver the best picture quality for mobile devices. Tone Mapping (TM) is a popular technique to enhance visual quality. However, the traditional implementation of Tone Mapping procedure is limited by pixel's value to value mapping, and the performance is restricted in terms of local sharpness and colorfulness. To overcome the drawbacks of traditional TM, we propose a spatial-frequency based framework in this paper. In the proposed solution, intensity component of an input video/image signal is split on low pass filtered (LPF) and high pass filtered (HPF) bands. Tone Mapping (TM) function is applied to LPF band to improve the global contrast/brightness, and HPF band is added back afterwards to keep the local contrast. The HPF band may be adjusted by a coring function to avoid noise boosting and signal overshooting. Colorfulness of an original image may be preserved or enhanced by chroma components correction by means of saturation function. Localized content adaptation is further improved by dividing an image to a set of non-overlapped regions and modifying each region individually. The suggested framework allows users to implement a wide range of tone mapping applications with perceptional local sharpness and colorfulness preserved or enhanced. Corresponding hardware circuit may be integrated in camera, video or display pipeline with minimal hardware budget

  15. Increased rhythmicity in hypertensive arterial smooth muscle is linked to transient receptor potential canonical channels

    DEFF Research Database (Denmark)

    Chen, Xiaoping; Yang, Dachun; Ma, Shuangtao;

    2010-01-01

    Vasomotion describes oscillations of arterial vascular tone due to synchronized changes of intracellular calcium concentrations. Since increased calcium influx into vascular smooth muscle cells from spontaneously hypertensive rats (SHR) has been associated with variances of transient receptor pot...

  16. English and Thai Speakers' Perception of Mandarin Tones

    Science.gov (United States)

    Li, Ying

    2016-01-01

    Language learners' language experience is predicted to display a significant effect on their accurate perception of foreign language sounds (Flege, 1995). At the superasegmental level, there is still a debate regarding whether tone language speakers are better able to perceive foreign lexical tones than non-tone language speakers (i.e Lee et al.,…

  17. Stress and Tone in Indo-Aryan Languages

    Science.gov (United States)

    Dhillon, Rajdip Kaur

    2010-01-01

    The current work offers a comprehensive examination of stress and tone in ten Indo-Aryan languages, providing novel analyses within Optimality Theory. The languages are divided into three categories: those in which tone is attracted to stress; those in which stress is attracted to tone; and those in which no interaction between stress and tone…

  18. Loudness of tone pulses in a free field

    DEFF Research Database (Denmark)

    Poulsen, Torben

    1981-01-01

    Investigations of temporal loudness summation of tone pulses have been performed. The investigations comprised equal loudness determinations between pairs of tone pulses with a duration ratio of 1:2, and threshold determinations of the same tone pulses. Pulse durations ranged from 5 to 640 ms. Th...

  19. Sequential Grouping of Pure-Tone Percepts Evoked by the Segregation of Components from a Complex Tone

    Science.gov (United States)

    Haywood, Nicholas R.; Roberts, Brian

    2011-01-01

    A sudden change applied to a single component can cause its segregation from an ongoing complex tone as a pure-tone-like percept. Three experiments examined whether such pure-tone-like percepts are organized into streams by extending the research of Bregman and Rudnicky (1975). Those authors found that listeners struggled to identify the…

  20. Auditory streaming of tones of uncertain frequency, level, and duration.

    Science.gov (United States)

    Chang, An-Chieh; Lutfi, Robert A; Lee, Jungmee

    2015-12-01

    Stimulus uncertainty is known to critically affect auditory masking, but its influence on auditory streaming has been largely ignored. Standard ABA-ABA tone sequences were made increasingly uncertain by increasing the sigma of normal distributions from which the frequency, level, or duration of tones were randomly drawn. Consistent with predictions based on a model of masking by Lutfi, Gilbertson, Chang, and Stamas [J. Acoust. Soc. Am. 134, 2160-2170 (2013)], the frequency difference for which A and B tones formed separate streams increased as a linear function of sigma in tone frequency but was much less affected by sigma in tone level or duration.

  1. Effet du sentiment de discrimination sur les trajectoires professionnelles

    OpenAIRE

    Joseph, Olivier; Lemière, Séverine; Lizé, Laurence; Rousset, Patrick

    2010-01-01

    Cette recherche porte sur les individus qui estiment avoir été victimes de discrimination, c'est-à-dire avoir subi un traitement inégal, de manière intentionnelle ou non, en raison de leur origine étrangère et/ou de leur couleur de peau. L'objectif est de s'intéresser au sentiment de discrimination et de chercher à évaluer son effet sur les parcours professionnels sept ans après la sortie du système éducatif. A partir de l'enquête Génération 98 du Céreq à 7 ans, nous avons utilisé la méthode ...

  2. Congenital amusia in speakers of a tone language: association with lexical tone agnosia.

    Science.gov (United States)

    Nan, Yun; Sun, Yanan; Peretz, Isabelle

    2010-09-01

    Congenital amusia is a neurogenetic disorder that affects the processing of musical pitch in speakers of non-tonal languages like English and French. We assessed whether this musical disorder exists among speakers of Mandarin Chinese who use pitch to alter the meaning of words. Using the Montreal Battery of Evaluation of Amusia, we tested 117 healthy young Mandarin speakers with no self-declared musical problems and 22 individuals who reported musical difficulties and scored two standard deviations below the mean obtained by the Mandarin speakers without amusia. These 22 amusic individuals showed a similar pattern of musical impairment as did amusic speakers of non-tonal languages, by exhibiting a more pronounced deficit in melody than in rhythm processing. Furthermore, nearly half the tested amusics had impairments in the discrimination and identification of Mandarin lexical tones. Six showed marked impairments, displaying what could be called lexical tone agnosia, but had normal tone production. Our results show that speakers of tone languages such as Mandarin may experience musical pitch disorder despite early exposure to speech-relevant pitch contrasts. The observed association between the musical disorder and lexical tone difficulty indicates that the pitch disorder as defining congenital amusia is not specific to music or culture but is rather general in nature. PMID:20685803

  3. A Dynamic Treatment of Tone with Special Attention to the Tonal System of Igbo.

    Science.gov (United States)

    Clark, Mary Morris

    An analysis of tone in language begins with the observation that the structural approach taken in segmental phonology, analyzing complex tones in terms of sequences of level tones, is not necessarily appropriate with tone languages. A different approach is proposed, a "dynamic-tone" theory that represents tone contours entirely in terms of two…

  4. KV 7.4 channels participate in the control of rodent renal vascular resting tone

    DEFF Research Database (Denmark)

    Salomonsson, M.; Brasen, Jens Christian; Braunstein, Thomas Hartig;

    2015-01-01

    .2–5 stimulator flupirtine dose-dependently relaxed isolated rat interlobar arteries and increased (approx. 5%) RBF in vivo. The RBF responses to NE or Ang II administration were not affected by pre-treatment with XE991 or flupirtine. XE991 pre-treatment caused a minor augmentation of the acetylcholine......-induced increase in RBF, while flupirtine pre-treatment did not affect this response. Conclusion: It is concluded that KV7 channels, via nifedipine sensitive channels, have a role in the regulation of basal renal vascular tone. There is no indication that KV7 channels have an effect on agonist-induced renal...

  5. Leptin augments cerebral hemodynamic reserve after three-vessel occlusion: distinct effects on cerebrovascular tone and proliferation in a nonlethal model of hypoperfused rat brain

    NARCIS (Netherlands)

    H.J. Busch; S.H. Schirmer; M. Jost; S. van Stijn; S.L.M. Peters; J.J. Piek; C. Bode; I.R. Buschmann; G. Mies

    2011-01-01

    The adipocytokine leptin has distinct functions regulating vascular tone, inflammation, and collateral artery growth. Arteriogenesis is an inflammatory process and provides a mechanism to overcome the effects of vascular obstruction. We, therefore, tested the effects of leptin in hypoperfused rat br

  6. SpicyTones- A food blog production

    OpenAIRE

    Pennanen, Eva

    2010-01-01

    This thesis is written to demonstrate the learning outcome of the author in creating a food blog project, named SpicyTones. The goals of the thesis are to create a successful food blog, to educate the society about Asian food and encourage them to cook at home. The objectives of the thesis are to obtain at least 50 followers, to keep the blog running for at least 3 months and to share out 12 themed recipes onto the blog. In this thesis, figures and tables are used in order to support the find...

  7. Arterial Ageing

    OpenAIRE

    Lee, Seung-Jun; Park, Sung-Ha

    2013-01-01

    Arterial ageing is characterized by age associated degeneration and sclerosis of the media layer of the large arteries. However, besides ageing, clinical conditions, which enhance oxidative stress and inflammation act to accelerate the degree of arterial ageing. In this review, we summarized the pathophysiology and contributing factors that accelerate arterial ageing. Among them, we focused on hypertension, the renin-angiotensin-aldosterone system and vascular inflammation which are modifiabl...

  8. Changes in Vascular Tone Occur Early During Hemodialysis Treatments Independently of Volume Reduction.

    Science.gov (United States)

    Power, Albert; Charitaki, Evangelia; Davenport, Andrew

    2016-07-01

    Hypotension commonly occurs during hemodialysis (HD). Hypotension can result from an absolute reduction in plasma volume following excessive ultrafiltration or from a reduction in vascular tone. We hypothesized that changes in vascular tone could occur during dialysis. Aortic pulse wave velocity (aPWV) was measured in 197 HD patients, mean age 63.3 ± 16.6 years, 62% male, 49% diabetic, during a single HD session. aPWV did not change (9.6 ± 2.2 vs. 9.6 ± 2.2 m/s) with HD. Systolic blood pressure (SBP) declined from 151 ± 31 to 147 ± 32 after 20 min and to 140 ± 36 mm Hg on completion of HD (P area (DRA) increased from 36.7 (27.9-46.3) to 40.4 (32.2-51) after 20 min and 47.1 (34.2-60.5) on completion of HD, P < 0.05. We report changes in arterial tone within 20 min of starting HD, when minimal ultrafiltration has occurred, suggesting that volume changes may not be the only predisposing cause of intradialytic hypotension. The combination of a fall in SBP and a rise in DRA would suggest a reduction in coronary blood flow in keeping with reports of "myocardial stunning" during HD. PMID:26496182

  9. FFT-DMAC:a tone based DMAC protocol

    Institute of Scientific and Technical Information of China (English)

    Li Ying; Li Minglu; Shu Wei; Wu Minyou

    2009-01-01

    This paper presents the flip-flop tone (FFT) DMAC protocol, a tone based MAC protocol using directional antennas to solve the deafness problem, hidden terminal and exposed terminal problems simultaneously. It uses two pairs of flip-flop tones. The first pair of tone is to send omni-directionally to reach every neighboring node to announce the start and the end of communication, and therefore to alleviate the deafness problem. The second pair of tone is to send directionally towards the sender. It is used to solve the hidden terminal problem as well as the exposed terminal problem. Evaluation shows that FFT-DMAC can achieve better performance compared to the 802.11 and ToneDMAC protocol.

  10. Effect of musical experience on learning lexical tone categories.

    Science.gov (United States)

    Zhao, T Christina; Kuhl, Patricia K

    2015-03-01

    Previous studies suggest that musicians show an advantage in processing and encoding foreign-language lexical tones. The current experiments examined whether musical experience influences the perceptual learning of lexical tone categories. Experiment I examined whether musicians with no prior experience of tonal languages differed from nonmusicians in the perception of a lexical tone continuum. Experiment II examined whether short-term perceptual training on lexical tones altered the perception of the lexical tone continuum differentially in English-speaking musicians and nonmusicians. Results suggested that (a) musicians exhibited higher sensitivity overall to tonal changes, but perceived the lexical tone continuum in a manner similar to nonmusicians (continuously), in contrast to native Mandarin speakers (categorically); and (b) short-term perceptual training altered perception; however, there were no significant differences between the effects of training on musicians and nonmusicians. PMID:25786956

  11. Perception of touch quality in piano tones.

    Science.gov (United States)

    Goebl, Werner; Bresin, Roberto; Fujinaga, Ichiro

    2014-11-01

    Both timbre and dynamics of isolated piano tones are determined exclusively by the speed with which the hammer hits the strings. This physical view has been challenged by pianists who emphasize the importance of the way the keyboard is touched. This article presents empirical evidence from two perception experiments showing that touch-dependent sound components make sounds with identical hammer velocities but produced with different touch forms clearly distinguishable. The first experiment focused on finger-key sounds: musicians could identify pressed and struck touches. When the finger-key sounds were removed from the sounds, the effect vanished, suggesting that these sounds were the primary identification cue. The second experiment looked at key-keyframe sounds that occur when the key reaches key-bottom. Key-bottom impact was identified from key motion measured by a computer-controlled piano. Musicians were able to discriminate between piano tones that contain a key-bottom sound from those that do not. However, this effect might be attributable to sounds associated with the mechanical components of the piano action. In addition to the demonstrated acoustical effects of different touch forms, visual and tactile modalities may play important roles during piano performance that influence the production and perception of musical expression on the piano.

  12. Memory for pure tone sequences without contour.

    Science.gov (United States)

    Lefebvre, Christine; Jolicœur, Pierre

    2016-06-01

    We presented pure tones interspersed with white noise sounds to disrupt contour perception in an acoustic short-term memory (ASTM) experiment during which we recorded the electroencephalogram. The memory set consisted of seven stimuli, 0, 1, 2, 3, or 4 of which were to-be-remembered tones. We estimated each participant׳s capacity, K, for each set size and measured the amplitude of the SAN (sustained anterior negativity, an ERP related to acoustic short-term memory). We correlated their K slopes with their SAN amplitude slopes as a function of set size, and found a significant link between performance and the SAN: a larger increase in SAN amplitude was linked with a larger number of stimuli maintained in ASTM. The SAN decreased in amplitude in the later portion of the silent retention interval, but the correlation between the SAN and capacity remained strong. These results show the SAN is not an index of contour but rather an index of the maintenance of individual objects in STM. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26903419

  13. Neuromagnetic responses to frequency modulation of a continuous tone.

    Science.gov (United States)

    Hari, R; Mäkelä, J P

    1986-01-01

    Neuromagnetic responses to frequency modulation of a continuous tone were studied in nine subjects. The latencies of the transient responses increased and the amplitudes decreased with decreasing speed of modulation. The equivalent dipoles for modulation of a 1,000 Hz tone were slightly but statistically significantly anterior to the dipoles activated by modulation of a 500 Hz tone. The generation mechanisms of N100m are discussed.

  14. Auditory pre-attentive processing of Chinese tones

    Institute of Scientific and Technical Information of China (English)

    YANG Li-jun; CAO Ke-li; WEI Chao-gang; LIU Yong-zhi

    2008-01-01

    Background Chinese tones are considered important in Chinese discrimination.However,the relevant reports on auditory central mechanisms concerning Chinese tones are limited.In this study,mismatch negativity (MMN),one of the event related potentials (ERP),was used to investigate pre-attentive processing of Chinese tones,and the differences between the function of oddball MMN and that of control MMN are discussed.Methods Ten subjects (six men and four women) with normal hearing participated in the study.A sequence was presented to these subjects through a loudspeaker,the sequence included four blocks,a control block and three oddball blocks.The control block was made up of five components (one pure tone and four Chinese tones) with equiprobability.The oddball blocks were made up of two components,one was a standard stimulus (tone 1) and the other was a deviant stimulus (tone 2 or tone 3 or tone 4).Electroencephalogram (EEG) data were recorded when the sequence was presented and MMNs were obtained from the analysis of the EEG data.Results Two kinds of MMNs were obtained,oddball MMN and control MMN.Oddball MMN was obtained by subtracting the ERP elicited by standard stimulation (tone 1) from that elicited by deviant stimulation (tone 2 or tone 3 or tone 4) in the oddball block; control MMN was obtained by subtracting the ERP elicited by the tone in control block,which was the same tone as the deviant stimulation in the oddball block,from the ERP elicited by deviant stimulation (tone 2 or tone 3 or tone 4)in the oddball block.There were two negative waves in oddball MMN,one appeared around 150 ms (oddball MMN 1),the other around 300 ms (oddball MMN 2).Only one negative wave appeared around 300 ms in control MMN,which was corresponding to the oddball MMN 2.We performed the statistical analyses in each paradigm for latencies and amplitudes for oddball MMN 2 in discriminating the three Chinese tones and reported no significant differences.But the latencies and amplitudes

  15. Determinants of an elevated pulmonary arterial pressure in patients with pulmonary arterial hypertension.

    Science.gov (United States)

    Sakao, Seiichiro; Voelkel, Norbert F; Tanabe, Nobuhiro; Tatsumi, Koichiro

    2015-01-01

    Given the difficulty of diagnosing early-stage pulmonary arterial hypertension (PAH) due to the lack of signs and symptoms, and the risk of an open lung biopsy, the precise pathological features of presymptomatic stage lung tissue remain unknown. It has been suggested that the maximum elevation of the mean pulmonary arterial pressure (P pa) is achieved during the early symptomatic stage, indicating that the elevation of the mean P pa is primarily driven by the pulmonary vascular tone and/or some degree of pulmonary vascular remodeling completed during this stage. Recently, the examination of a rat model of severe PAH suggested that the severe PAH may be primarily determined by the presence of intimal lesions and/or the vascular tone in the early stage. Human data seem to indicate that intimal lesions are essential for the severely increased pulmonary arterial blood pressure in the late stage of the disease.However, many questions remain. For instance, how does the pulmonary hemodynamics change during the course of the disease, and what drives the development of severe PAH? Although it is generally acknowledged that both pulmonary vascular remodeling and the vascular tone are important determinants of an elevated pulmonary arterial pressure, which is the root cause of the time-dependent progression of the disease? Here we review the recent histopathological concepts of PAH with respect to the progression of the lung vascular disease.

  16. Raynaud's phenomenon in arterial obstructive disease of the hand demonstrated by locally provoked cooling

    DEFF Research Database (Denmark)

    Nielsen, Steen Levin; Nobin, B A; Hirai, M;

    1978-01-01

    Finger systolic blood pressure (FSP) was measured by cuff technique before and after local cooling in three groups of patients (Raynaud's disease (7), subclavian stenoses, (5), thrombo-angiitis obliterans (15)), and in 15 normals. The response to finger cooling registered as a decrease in FSP...... indicates an increase of digital arterial tone. In all three groups, digital arterial tone increased more than in normals during finger cooling. Patients with Raynaud's disease showed a pathological increase in arterial tone at 23.5 degrees C with closure of the digital arteries at a mean temperature of 18.......5 degrees C. The temperature eliciting these phenomena in patients with thrombo-angiitis obliterans was about 7 degrees C lower (16.5 and 11.0 degrees C, respectively). Accordingly, cold sensitivity and Raynaud's phenomena in the two groups may have a different pathophysiological mechanism, namely...

  17. Tune in to the Tone: Lexical Tone Identification is Associated with Vocabulary and Word Recognition Abilities in Young Chinese Children.

    Science.gov (United States)

    Tong, Xiuli; Tong, Xiuhong; McBride-Chang, Catherine

    2015-12-01

    Lexical tone is one of the most prominent features in the phonological representation of words in Chinese. However, little, if any, research to date has directly evaluated how young Chinese children's lexical tone identification skills contribute to vocabulary acquisition and character recognition. The present study distinguished lexical tones from segmental phonological awareness and morphological awareness in order to estimate the unique contribution of lexical tone in early vocabulary acquisition and character recognition. A sample of 199 Cantonese children aged 5-6 years was assessed on measures of lexical tone identification, segmental phonological awareness, morphological awareness, nonverbal ability, vocabulary knowledge, and Chinese character recognition. It was found that lexical tone awareness and morphological awareness were both associated with vocabulary knowledge and character recognition. However, there was a significant relationship between lexical tone awareness and both vocabulary knowledge and character recognition, even after controlling for the effects of age, nonverbal ability, segmental phonological awareness and morphological awareness. These findings suggest that lexical tone is a key factor accounting for individual variance in young children's lexical acquisition in Chinese, and that lexical tone should be considered in understanding how children learn new Chinese vocabulary words, in either oral or written forms. PMID:27483739

  18. Tune in to the Tone: Lexical Tone Identification is Associated with Vocabulary and Word Recognition Abilities in Young Chinese Children.

    Science.gov (United States)

    Tong, Xiuli; Tong, Xiuhong; McBride-Chang, Catherine

    2015-12-01

    Lexical tone is one of the most prominent features in the phonological representation of words in Chinese. However, little, if any, research to date has directly evaluated how young Chinese children's lexical tone identification skills contribute to vocabulary acquisition and character recognition. The present study distinguished lexical tones from segmental phonological awareness and morphological awareness in order to estimate the unique contribution of lexical tone in early vocabulary acquisition and character recognition. A sample of 199 Cantonese children aged 5-6 years was assessed on measures of lexical tone identification, segmental phonological awareness, morphological awareness, nonverbal ability, vocabulary knowledge, and Chinese character recognition. It was found that lexical tone awareness and morphological awareness were both associated with vocabulary knowledge and character recognition. However, there was a significant relationship between lexical tone awareness and both vocabulary knowledge and character recognition, even after controlling for the effects of age, nonverbal ability, segmental phonological awareness and morphological awareness. These findings suggest that lexical tone is a key factor accounting for individual variance in young children's lexical acquisition in Chinese, and that lexical tone should be considered in understanding how children learn new Chinese vocabulary words, in either oral or written forms.

  19. Shear Stress, Reactive Oxygen Species, and Arterial Structure and Function

    NARCIS (Netherlands)

    H.L. Matlung; E.N. Bakker; E. VanBavel

    2009-01-01

    Shear stress is well known to be a key factor in the regulation of small-artery tone and structure. Although nitric oxide is a major endothelium-derived factor involved in short-and long-term regulation of vascular caliber, it is clear that other mechanisms also can be involved. This review discusse

  20. Classical conditioned responses to absent tones

    Directory of Open Access Journals (Sweden)

    Häusler Udo

    2006-08-01

    Full Text Available Abstract Background Recent evidence for a tight coupling of sensorimotor processes in trained musicians led to the question of whether this coupling extends to preattentively mediated reflexes; particularly, whether a classically conditioned response in one of the domains (auditory is generalized to another (tactile/motor on the basis of a prior association in a second-order Pavlovian paradigm. An eyeblink conditioning procedure was performed in 17 pianists, serving as a model for overlearned audiomotor integration, and 14 non-musicians. Results: During the training session, subjects were conditioned to respond to auditory stimuli (piano tones. During a subsequent testing session, when subjects performed keystrokes on a silent piano, pianists showed significantly higher blink rates than non-musicians. Conclusion These findings suggest a tight coupling of the auditory and motor domains in musicians, pointing towards training-dependent mechanisms of strong cross-modal sensorimotor associations even on sub-cognitive processing levels.

  1. Disorders of pitch production in tone deafness

    Directory of Open Access Journals (Sweden)

    Simone eDalla Bella

    2011-07-01

    Full Text Available Singing is as natural as speaking for the majority of people. Yet some individuals (i.e., 10-15% are inaccurate singers, typically performing or imitating pitches and melodies inaccurately. This condition, commonly referred to as tone deafness, has been observed both in the presence and absence of deficient pitch perception. In this article we review the existing literature concerning normal singing, poor-pitch singing, and, briefly, the sources of this condition. Considering that pitch plays a prominent role in the structure of both music and speech we also focus on the possibility that pitch production (or imitation is similarly impaired in poor-pitch singers. Preliminary evidence from our laboratory on poor-pitch singing suggests that pitch imitation may be selectively inaccurate in the music domain without being affected in speech. This finding points to separability of mechanisms subserving pitch production in music and language.

  2. Disorders of pitch production in tone deafness.

    Science.gov (United States)

    Bella, Simone Dalla; Berkowska, Magdalena; Sowiński, Jakub

    2011-01-01

    Singing is as natural as speaking for the majority of people. Yet some individuals (i.e., 10-15%) are poor singers, typically performing or imitating pitches and melodies inaccurately. This condition, commonly referred to as "tone deafness," has been observed both in the presence and absence of deficient pitch perception. In this article we review the existing literature concerning normal singing, poor-pitch singing, and, briefly, the sources of this condition. Considering that pitch plays a prominent role in the structure of both music and speech we also focus on the possibility that speech production (or imitation) is similarly impaired in poor-pitch singers. Preliminary evidence from our laboratory suggests that pitch imitation may be selectively inaccurate in the music domain without being affected in speech. This finding points to separability of mechanisms subserving pitch production in music and language.

  3. When does a sung tone start?

    Science.gov (United States)

    Sundberg, Johan; Bauer-Huppmann, Julia

    2007-05-01

    Although the consonant is mostly considered as the start of a syllable in phonetics and orthography, musicians generally agree that the vowel onset in singing should be synchronized with the beat. As a test of this assumption, the current investigation analyzes the time interval between vowel onsets and piano accompaniment onsets in a set of songs performed by international vocal artists and published on commercial CD recordings. The results show that, most commonly, the accompanists synchronized their tones with the singers' vowel onsets. Nevertheless, examples of lead and lag were found, probably made for expressive purposes. The lead and lag varied greatly between songs, being smallest in a song performed in a fast tempo and longest in a song performed in a slow tempo. PMID:16564674

  4. Factors Influencing Sensitivity to Lexical Tone in an Artificial Language: Implications for Second Language Learning

    Science.gov (United States)

    Caldwell-Harris, Catherine L.; Lancaster, Alia; Ladd, D. Robert; Dediu, Dan; Christiansen, Morten H.

    2015-01-01

    This study examined whether musical training, ethnicity, and experience with a natural tone language influenced sensitivity to tone while listening to an artificial tone language. The language was designed with three tones, modeled after level-tone African languages. Participants listened to a 15-min random concatenation of six 3-syllable words.…

  5. Analysis on the relations between piano touch and tone

    CERN Document Server

    Nie, Lai-Mei

    2010-01-01

    In piano playing, different ways of touch lead to different tones. The effects of changing forces on keys are presented by changing interaction between hammer and string. The thesis focuses on several important variables in hammer-string system and draws conclusions to the question about piano touch and tone.

  6. Slide rule-type color chart predicts reproduced photo tones

    Science.gov (United States)

    Griffin, J. D.

    1966-01-01

    Slide rule-type color chart determines the final reproduced gray tones in the production of briefing charts that are photographed in black and white. The chart shows both the color by drafting paint manufacturers name and mixture number, and the gray tone resulting from black and white photographic reproduction.

  7. Pilot tones in WDM networks with wavelength converters

    DEFF Research Database (Denmark)

    Kloch, Allan; Mikkelsen, Benny; Stubkjær, Kristian

    1997-01-01

    Here we investigate the transmission of a pilot tone through an interferometric wavelength converter (IWC) in conjunction with a 2.5 Gbit/s experiment. The pilot tone is added by sinusoidal modulation of the bias current to the signal laser. After the IWC (Michelson interferometer) the converted...

  8. Dissimilation in the Second Language Acquisition of Mandarin Chinese Tones

    Science.gov (United States)

    Zhang, Hang

    2016-01-01

    This article extends Optimality Theoretic studies to the research on second language tone phonology. Specifically, this work analyses the acquisition of identical tone sequences in Mandarin Chinese by adult speakers of three non-tonal languages: English, Japanese and Korean. This study finds that the learners prefer not to use identical lexical…

  9. One-tone suppression in the frog auditory nerve

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Jørgensen, M B

    1996-01-01

    Sixty-seven fibers of a sample of 401 in the auditory nerve of grassfrogs (Rana temporaria) showed one-tone suppression, i.e., their spontaneous activity was suppressed by tones. All fibers were afferents from the amphibian papilla with best frequencies between 100 and 400 Hz. Best suppression...

  10. Musical experience and Mandarin tone discrimination and imitation

    Science.gov (United States)

    Gottfried, Terry L.; Staby, Ann M.; Ziemer, Christine J.

    2001-05-01

    Previous work [T. L. Gottfried and D. Riester, J. Acoust. Soc. Am. 108, 2604 (2000)] showed that native speakers of American English with musical training performed better than nonmusicians when identifying the four distinctive tones of Mandarin Chinese (high-level, mid-rising, low-dipping, high-falling). Accuracy for both groups was relatively low since listeners were not trained on the phonemic contrasts. Current research compares musicians and nonmusicians on discrimination and imitation of unfamiliar tones. Listeners were presented with two different Mandarin words that had either the same or different tones; listeners indicated whether the tones were same or different. Thus, they were required to determine a categorical match (same or different tone), rather than an auditory match. All listeners had significantly more difficulty discriminating between mid-rising and low-dipping tones than with other contrasts. Listeners with more musical training showed significantly greater accuracy in their discrimination. Likewise, musicians' spoken imitations of Mandarin tones (model tokens presented by a native speaker) were rated as significantly more native-like than those of nonmusicians. These findings suggest that musicians may have abilities or training that facilitate their perception and production of Mandarin tones. However, further research is needed to determine whether this advantage transfers to language learning situations.

  11. Tone sandhi, prosodic phrasing, and focus marking in Wenzhou Chinese

    NARCIS (Netherlands)

    Scholz, Franziska

    2012-01-01

    In most languages, focus (i.e. highlighting information) is marked by modifying the melody of the sentence. But how is focus marked in a Chinese dialect with eight different citation tones and a complex tonal phonology? This thesis investigates the connection between tonal realization and tone chang

  12. Improving Tone Recognition with Nucleus Modeling and Sequential Learning

    Science.gov (United States)

    Wang, Siwei

    2010-01-01

    Mandarin Chinese and many other tonal languages use tones that are defined as specific pitch patterns to distinguish syllables otherwise ambiguous. It had been shown that tones carry at least as much information as vowels in Mandarin Chinese [Surendran et al., 2005]. Surprisingly, though, many speech recognition systems for Mandarin Chinese have…

  13. Prosodic Transfer: From Chinese Lexical tone to English Pitch Accent

    Directory of Open Access Journals (Sweden)

    Marie Ploquin

    2013-01-01

    Full Text Available Chinese tones are associated with a syllable to convey meaning, English pitch accents are prominence markers associated with stressed syllables.  As both are created by pitch modulation, their pitch contours can be quite similar.  The experiment reported here examines whether native speakers of Chinese produce, when speaking English, the Chinese tone whose phonetic contour most closely matches the contour of the intended English pitch accent.  Six native speakers of Chinese recorded English and Chinese sentences, all including the segment [fan].  Results show that the subjects produced a Chinese tone 2 where a rising pitch accents was required and thus that speakers of Chinese rely on their lexical tones inventory to produce English prosody. The results obtained with falling pitch accents are much less conclusive partly because of the difficulty in measuring tone 3 due to the high level of creak that accompanies it.

  14. EFFETS DES AFFAISSEMENTS MINIERS SUR LES CONSTRUCTIONS DANS LE BASSIN HOUILLER DU ZONGULDAK-TURQUIE

    Directory of Open Access Journals (Sweden)

    Ali İhsan EROL

    1996-02-01

    Full Text Available Dans les zones ou l'on effectue des travaux d'exploitation sous-jacente, il se cree des affaisemenets de surface par suite d'extraction de houille ainsi qu'ils sont aussi vus dans le Bassin Houiller de Zonguldak. En cet article, apres avoir reconnu brievement le Bassin Houiller du Zonguldak, les effets dus aux affaissements miniers sont expliques. Puis les dommages d'affaissements observes et l'etat existant de Bassin du Zonguldak du point de vue des effets sur les batiments d'affaissement minier sont examines. Ensuite les mesures de protection des batiments contre les effets d'affaissement et les propositions de solution qui interessent au Bassin de Zonguldak sont presentees.

  15. Effects of Early Bilingual Experience with a Tone and a Non-Tone Language on Speech-Music Integration

    NARCIS (Netherlands)

    Asaridou, S.S.; Hagoort, P.; McQueen, J.M.

    2015-01-01

    We investigated music and language processing in a group of early bilinguals who spoke a tone language and a non-tone language (Cantonese and Dutch). We assessed online speech-music processing interactions, that is, interactions that occur when speech and music are processed simultaneously in songs,

  16. Dispositifs de formation hybrides : quels effets sur le développement professionnel des enseignants ?

    OpenAIRE

    Charlier, Bernadette; Lameul, Geneviève; Peltier, Claire; Borruat, Stéphanie; Mancuso, Giovanna; Burton, Réginald

    2012-01-01

    Cette contribution présente le cadre théorique, la méthodologie et les premiers résultats de la recherche Hy-Sup relatifs aux effets des dispositifs de formation hybrides sur le développement professionnel des enseignants. Plus précisément, notre analyse porte sur la perception de l’évolution des pratiques d’enseignement et de l’engagement professionnel d’enseignants impliqués dans l’expérimentation d’un dispositif hybride. Dans cette perspective, des effets différenciés selon le type de disp...

  17. Attention deficits revealed by passive auditory change detection for pure tones and lexical tones in ADHD children.

    Science.gov (United States)

    Yang, Ming-Tao; Hsu, Chun-Hsien; Yeh, Pei-Wen; Lee, Wang-Tso; Liang, Jao-Shwann; Fu, Wen-Mei; Lee, Chia-Ying

    2015-01-01

    Inattention (IA) has been a major problem in children with attention deficit/hyperactivity disorder (ADHD), accounting for their behavioral and cognitive dysfunctions. However, there are at least three processing steps underlying attentional control for auditory change detection, namely pre-attentive change detection, involuntary attention orienting, and attention reorienting for further evaluation. This study aimed to examine whether children with ADHD would show deficits in any of these subcomponents by using mismatch negativity (MMN), P3a, and late discriminative negativity (LDN) as event-related potential (ERP) markers, under the passive auditory oddball paradigm. Two types of stimuli-pure tones and Mandarin lexical tones-were used to examine if the deficits were general across linguistic and non-linguistic domains. Participants included 15 native Mandarin-speaking children with ADHD and 16 age-matched controls (across groups, age ranged between 6 and 15 years). Two passive auditory oddball paradigms (lexical tones and pure tones) were applied. The pure tone oddball paradigm included a standard stimulus (1000 Hz, 80%) and two deviant stimuli (1015 and 1090 Hz, 10% each). The Mandarin lexical tone oddball paradigm's standard stimulus was /yi3/ (80%) and two deviant stimuli were /yi1/ and /yi2/ (10% each). The results showed no MMN difference, but did show attenuated P3a and enhanced LDN to the large deviants for both pure and lexical tone changes in the ADHD group. Correlation analysis showed that children with higher ADHD tendency, as indexed by parents' and teachers' ratings on ADHD symptoms, showed less positive P3a amplitudes when responding to large lexical tone deviants. Thus, children with ADHD showed impaired auditory change detection for both pure tones and lexical tones in both involuntary attention switching, and attention reorienting for further evaluation. These ERP markers may therefore be used for the evaluation of anti-ADHD drugs that aim to

  18. Attention deficits revealed by passive auditory change detection for pure tones and lexical tones in ADHD children

    Directory of Open Access Journals (Sweden)

    Ming-Tao eYang

    2015-08-01

    Full Text Available Inattention has been a major problem in children with attention deficit/hyperactivity disorder (ADHD, accounting for their behavioral and cognitive dysfunctions. However, there are at least three processing steps underlying attentional control for auditory change detection, namely pre-attentive change detection, involuntary attention orienting, and attention reorienting for further evaluation. This study aimed to examine whether children with ADHD would show deficits in any of these subcomponents by using mismatch negativity (MMN, P3a, and late discriminative negativity (LDN as event-related potential (ERP markers, under the passive auditory oddball paradigm. Two types of stimuli - pure tones and Mandarin lexical tones - were used to examine if the deficits were general across linguistic and non-linguistic domains. Participants included 15 native Mandarin-speaking children with ADHD and 16 age-matched controls (across groups, age ranged between 6 and 15 years. Two passive auditory oddball paradigms (lexical tones and pure tones were applied. Pure tone paradigm included standard stimuli (1000 Hz, 80% and two deviant stimuli (1015 Hz and 1090 Hz, 10% each. The Mandarin lexical tone paradigm’s standard stimuli was /yi3/ (80% and two deviant stimuli were /yi1/ and /yi2/ (10% each. The results showed no MMN difference, but did show attenuated P3a and enhanced LDN to the large deviants for both pure and lexical tone changes in the ADHD group. Correlation analysis showed that children with higher ADHD tendency, as indexed by parents’ and teachers’ rating on ADHD symptoms, showed less positive P3a amplitudes when responding to large lexical tone deviants. Thus, children with ADHD showed impaired auditory change detection for both pure tones and lexical tones in both involuntary attention switching, and attention reorienting for further evaluation. These ERP markers may therefore be used for evaluation of anti-ADHD drugs that aim to alleviate these

  19. The effect of SRS on pilot-tone detection technique in DWDM system

    Institute of Scientific and Technical Information of China (English)

    Zhiguo Gao(高志国); Minghua Chen(陈明华); Hongwei Chen(陈宏伟); Shizhong Xie(谢世钟)

    2004-01-01

    A math model that can describe the effect of stimulated Raman scattering (SRS) on pilot-tone detection technique is proposed. Thrugh numerical simulation, it is shown that the effect of SRS could produce ghost-tones. The power of ghost-tones was larger for the channels separated further from the real-tone.The power ratio between real-tone and ghost-tones increases linearly with the increase of transmission length when propagation distance longer than 300 km.

  20. School burnout: increased sympathetic vasomotor tone and attenuated ambulatory diurnal blood pressure variability in young adult women.

    Science.gov (United States)

    May, Ross W; Sanchez-Gonzalez, Marcos A; Fincham, Frank D

    2015-01-01

    Two studies examined autonomic and cardiovascular functioning that may link school burnout to cardiovascular risk factors in young healthy adult females. Study 1 (N = 136) investigated whether school burnout was related to resting values of blood pressure (BP) and blood pressure variability (BPV) through laboratory beat-to-beat BP assessment. Study 2 (N = 94) examined the link between school burnout and diurnal BPV through ambulatory BP monitoring. Controlling for anxiety and depressive symptomatology, school burnout demonstrated strong positive relationships with indices of cardiac sympathovagal tone, sympathetic vasomotor tone, inefficient myocardial oxygen consumption, increased 24-h ambulatory heart rate and BP, blunted BP diurnal variability, and increased arterial stiffness. These studies establish cardiovascular biomarkers of school burnout and suggest that even in a seemingly healthy sample school burnout may predispose females to increased cardiovascular risk. Several future lines of research are outlined.

  1. The Neural Substrates Underlying the Implementation of Phonological Rule in Lexical Tone Production: An fMRI Study of the Tone 3 Sandhi Phenomenon in Mandarin Chinese.

    Science.gov (United States)

    Chang, Claire H C; Kuo, Wen-Jui

    2016-01-01

    This study examined the neural substrates underlying the implementation of phonological rule in lexical tone by the Tone 3 sandhi phenomenon in Mandarin Chinese. Tone 3 sandhi is traditionally described as the substitution of Tone 3 with Tone 2 when followed by another Tone 3 (33 →23) during speech production. Tone 3 sandhi enables the examination of tone processing in the phonological level with the least involvement of segments. Using the fMRI technique, we measured brain activations corresponding to the monosyllable and disyllable sequences of the four Chinese lexical tones, while manipulating the requirement on overt oral response. The application of Tone 3 sandhi to disyllable sequence of Tone 3 was confirmed by our behavioral results. Larger brain responses to overtly produced disyllable Tone 3 (33 > 11, 22, and 44) were found in right posterior IFG by both whole-brain and ROI analyses. We suggest that the right IFG was responsible for the processing of Tone 3 sandhi. Intense temporo-frontal interaction is needed in speech production for self-monitoring. The involvement of the right IFG in tone production might result from its interaction with the right auditory cortex, which is known to specialize in pitch. Future studies using tools with better temporal resolutions are needed to illuminate the dynamic interaction between the right inferior frontal regions and the left-lateralized language network in tone languages.

  2. Perceptual Weights for Loudness Judgments of 6-Tone Complexes

    DEFF Research Database (Denmark)

    Jesteadt, Walt; Valente, Daniel L.; Joshi, Suyash Narendra

    In a series of studies, 6 subjects with normal hearing (NH) and 3 with sensorineural hearing loss (SNHL) judged the overall loudness of 6-tone complexes comprised of octave frequencies from 0.25 to 8 kHz. In two tasks, tones were equated in level in dB SPL or in sensation level (SL) and a range of...... 6-tone complexes, were highly correlated with those from the other tasks. Simulation of these experiments using a model of loudness perception [Moore and Glasberg, J. Hear Res. 188 (70-88)] yielded weights for these stimuli that were highly correlated with specific loudness, but the observed weights...

  3. Arterial Stiffness and Dialysis Calcium Concentration

    Directory of Open Access Journals (Sweden)

    Fabrice Mac-Way

    2011-01-01

    Full Text Available Arterial stiffness is the major determinant of isolated systolic hypertension and increased pulse pressure. Aortic stiffness is also associated with increased cardiovascular morbidity and mortality in patients with chronic kidney disease, hypertension, and general population. Hemodynamically, arterial stiffness results in earlier aortic pulse wave reflection leading to increased cardiac workload and decreased myocardial perfusion. Although the clinical consequence of aortic stiffness has been clearly established, its pathophysiology in various clinical conditions still remains poorly understood. The aim of the present paper is to review the studies that have looked at the impact of dialysis calcium concentration on arterial stiffness. Overall, the results of small short-term studies suggest that higher dialysis calcium is associated with a transient but significant increase in arterial stiffness. This calcium dependant increase in arterial stiffness is potentially explained by increased vascular smooth muscle tone of the conduit arteries and is not solely explained by changes in mean blood pressure. However, the optimal DCa remains to be determined, and long term studies are required to evaluate its impact on the progression of arterial stiffness.

  4. Effets des electrons secondaires sur l'ADN

    Science.gov (United States)

    Boudaiffa, Badia

    Les interactions des electrons de basse energie (EBE) representent un element important en sciences des radiations, particulierement, les sequences se produisant immediatement apres l'interaction de la radiation ionisante avec le milieu biologique. Il est bien connu que lorsque ces radiations deposent leur energie dans la cellule, elles produisent un grand nombre d'electrons secondaires (4 x 104/MeV), qui sont crees le long de la trace avec des energies cinetiques initiales bien inferieures a 20 eV. Cependant, il n'y a jamais eu de mesures directes demontrant l'interaction de ces electrons de tres basse energie avec l'ADN, du principalement aux difficultes experimentales imposees par la complexite du milieu biologique. Dans notre laboratoire, les dernieres annees ont ete consacrees a l'etude des phenomenes fondamentaux induits par impact des EBE sur differentes molecules simples (e.g., N2, CO, O2, H2O, NO, C2H 4, C6H6, C2H12) et quelques molecules complexes dans leur phase solide. D'autres travaux effectues recemment sur des bases de l'ADN et des oligonucleotides ont montre que les EBE produisent des bris moleculaires sur les biomolecules. Ces travaux nous ont permis d'elaborer des techniques pour mettre en evidence et comprendre les interactions fondamentales des EBE avec des molecules d'interet biologique, afin d'atteindre notre objectif majeur d'etudier l'effet direct de ces particules sur la molecule d'ADN. Les techniques de sciences des surfaces developpees et utilisees dans les etudes precitees peuvent etre etendues et combinees avec des methodes classiques de biologie pour etudier les dommages de l'ADN induits par l'impact des EBE. Nos experiences ont montre l'efficacite des electrons de 3--20 eV a induire des coupures simple et double brins dans l'ADN. Pour des energies inferieures a 15 eV, ces coupures sont induites par la localisation temporaire d'un electron sur une unite moleculaire de l'ADN, ce qui engendre la formation d'un ion negatif transitoire

  5. Global Database of Events, Language, and Tone (GDELT Project)

    Data.gov (United States)

    World Wide Human Geography Data Working Group — The Global Database of Events, Language, and Tone (GDELT Project) monitors the world's broadcast, print, and web news from nearly every corner of every country in...

  6. Effect of harmonic rank on the streaming of complex tones

    DEFF Research Database (Denmark)

    Madsen, Sara Miay Kim; Dau, Torsten; Moore, Brian C.J.

    2015-01-01

    The effect of the rank of the harmonics on sequential stream segregation of complex tones was investigated for normal-hearing participants with no musical training. It was hypothesized that stream segregation would be greater for tones with high pitch salience, as assessed by fundamental frequency....... There was a significant trend for less stream segregation with increasing harmonic rank. The amount of stream segregation was inversely correlated with the f0 difference limens, consistent with the hypothesis....

  7. Tone-3 Accent Realization in Short Chinese Sentences

    Institute of Scientific and Technical Information of China (English)

    CAO Wen; ZHANG Jinsong

    2008-01-01

    To investigate how a low tone (tone-3,T3) syllable in Chinese can be perceived to be focal ac-canted or not,a total of 156 sentences containing tone-3 words were synthesized and used as stimuli in a perceptual study.The sentences differed in the falling value between the two high pitches,and in the dura-tion and phonation types of the T3 syllables.Thirty-nine subjects were asked to judge where the focus or accent was for each sentence.The results show that at least three degrees of pitch drop are involved in the focus recognition: a big sized drop of about 10 semitones; a middle sized drop of about 6 semitones; a small sized drop of about 2 semitones.The results suggest that the three sizes of pitch drop have different indica-tions in Chinese intonation,depending on both the tone and the tone combination.In perception,there are various ways to realize tone-3 focus in the Tx-T3-Ty sentences series,but in production or for text-to-speech synthesis,the rule simply is making a middle sized pitch drop with a long and creaky T3 syllable.Similarly,to focus on the low tone syllable in the T3-Tx-Ty sentences,a creaky T3 syllable is essential.However,a long T3 syllable is a strong determinant for a low tone focus in the Tx-Ty-T3 sentences.

  8. Pilot tone modulation used for channel identification in OTDM networks

    DEFF Research Database (Denmark)

    Clausen, Anders; Bennike, Jon; Oxenløwe, Leif Katsuo;

    2004-01-01

    The principle of applying a pilot tone to an OTDM signal, in order to identify a specific channel, is presented. The impact on BER system performance is characterised as function of modulation index.......The principle of applying a pilot tone to an OTDM signal, in order to identify a specific channel, is presented. The impact on BER system performance is characterised as function of modulation index....

  9. Production and Perception of Tone 3 Focus in Mandarin Chinese.

    Science.gov (United States)

    Lee, Yong-Cheol; Wang, Ting; Liberman, Mark

    2016-01-01

    This study uses production and perception experiments to explore tone 3 focus in Mandarin Chinese. Overall, contrastive focus in Mandarin is clearly marked with increased duration, intensity, and pitch range: in the experiments, listeners identified focused syllables correctly more than 90% of the time. However, a tone 3 syllable offers a smaller capacity for pitch range expansion under focus, and also yields less intensity increase; in addition, local dissimilation increases the duration, intensity, and pitch range of adjacent syllables within the same phrase as a focused tone 3 syllable. As a result, tone 3 focus was less well identified by listeners (77.1%). We suggest that the relatively poor identification of tone 3 focus is due to the smaller capacity for pitch range expansion, the confusion from within-phrase local dissimilatory effects, and the relatively weak intensity of tone 3. This study demonstrates that even within a language where purely prosodic marking of focus is clear, the location of prosodic focus can be difficult to identify in certain circumstances. Our results underline the conclusion, established in other work, that prosodic marking of focus is not universal, but is expressed through the prosodic system of each language.

  10. Production and Perception of Tone 3 Focus in Mandarin Chinese

    Science.gov (United States)

    Lee, Yong-Cheol; Wang, Ting; Liberman, Mark

    2016-01-01

    This study uses production and perception experiments to explore tone 3 focus in Mandarin Chinese. Overall, contrastive focus in Mandarin is clearly marked with increased duration, intensity, and pitch range: in the experiments, listeners identified focused syllables correctly more than 90% of the time. However, a tone 3 syllable offers a smaller capacity for pitch range expansion under focus, and also yields less intensity increase; in addition, local dissimilation increases the duration, intensity, and pitch range of adjacent syllables within the same phrase as a focused tone 3 syllable. As a result, tone 3 focus was less well identified by listeners (77.1%). We suggest that the relatively poor identification of tone 3 focus is due to the smaller capacity for pitch range expansion, the confusion from within-phrase local dissimilatory effects, and the relatively weak intensity of tone 3. This study demonstrates that even within a language where purely prosodic marking of focus is clear, the location of prosodic focus can be difficult to identify in certain circumstances. Our results underline the conclusion, established in other work, that prosodic marking of focus is not universal, but is expressed through the prosodic system of each language. PMID:27507951

  11. Examination of voicing onset time during Mandarin tone productions

    Science.gov (United States)

    Chen, Yang; Ng, Manwa

    2005-04-01

    The voice onset time (VOT) of stop consonant is defined as the time interval between the release of a stop and the onset of the following vowel (Lisker and Abramson, 1964, 1970). Previous studies indicated that VOT could be used as a perceptual cue for identification of both voicing and place of articulation of stops (Kewley-Port, 1983; Ladefoged, 2001). Abramson (1977) suggested VOT could be interpreted as interrelated acoustic consequences of variation in the relative timing of glottal and oral gestures. This study will attempt to extend the probe on this suggestion by comparing the VOT values among different tones. Mandarin, which is a tone language, where a change in the tone of a syllable leads to a change in meaning, will be used in the study. There are four contrastive tones in Mandarin, each of which is realized by changing the vocal pitch during the course of the syllable production. The proposed study will determine if VOT values for each of the six stop sounds (/p,b,t,d,k,g/) will vary with the variation of different tones at which each of the following vowel sounds is produced. The interrelationship between VOT and tone production will be discussed.

  12. The vascular Ca2+-sensing receptor regulates blood vessel tone and blood pressure.

    Science.gov (United States)

    Schepelmann, M; Yarova, P L; Lopez-Fernandez, I; Davies, T S; Brennan, S C; Edwards, P J; Aggarwal, A; Graça, J; Rietdorf, K; Matchkov, V; Fenton, R A; Chang, W; Krssak, M; Stewart, A; Broadley, K J; Ward, D T; Price, S A; Edwards, D H; Kemp, P J; Riccardi, D

    2016-02-01

    The extracellular calcium-sensing receptor CaSR is expressed in blood vessels where its role is not completely understood. In this study, we tested the hypothesis that the CaSR expressed in vascular smooth muscle cells (VSMC) is directly involved in regulation of blood pressure and blood vessel tone. Mice with targeted CaSR gene ablation from vascular smooth muscle cells (VSMC) were generated by breeding exon 7 LoxP-CaSR mice with animals in which Cre recombinase is driven by a SM22α promoter (SM22α-Cre). Wire myography performed on Cre-negative [wild-type (WT)] and Cre-positive (SM22α)CaSR(Δflox/Δflox) [knockout (KO)] mice showed an endothelium-independent reduction in aorta and mesenteric artery contractility of KO compared with WT mice in response to KCl and to phenylephrine. Increasing extracellular calcium ion (Ca(2+)) concentrations (1-5 mM) evoked contraction in WT but only relaxation in KO aortas. Accordingly, diastolic and mean arterial blood pressures of KO animals were significantly reduced compared with WT, as measured by both tail cuff and radiotelemetry. This hypotension was mostly pronounced during the animals' active phase and was not rescued by either nitric oxide-synthase inhibition with nitro-l-arginine methyl ester or by a high-salt-supplemented diet. KO animals also exhibited cardiac remodeling, bradycardia, and reduced spontaneous activity in isolated hearts and cardiomyocyte-like cells. Our findings demonstrate a role for CaSR in the cardiovascular system and suggest that physiologically relevant changes in extracellular Ca(2+) concentrations could contribute to setting blood vessel tone levels and heart rate by directly acting on the cardiovascular CaSR.

  13. The Case-Tone Factor in Igbo Nouns, with Special Reference to the Igbo Associative Construction.

    Science.gov (United States)

    Echeruo, Michael J. C.

    Tone-based classification rules for Igbo nouns need modification because: (1) class 1 nouns (monosyllables with high tones) do not, as claimed, operate differently from other terminal high-tone nouns; and (2) class 6 nouns (di-syllabic with downstep tones) can be accounted for within class 2 and class 3 nouns known as HH and LH nouns). The proper…

  14. Carotid artery surgery

    Science.gov (United States)

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... through the catheter around the blocked area during surgery. Your carotid artery is opened. The surgeon removes ...

  15. Role of Mitochondria in Cerebral Vascular Function: Energy Production, Cellular Protection, and Regulation of Vascular Tone.

    Science.gov (United States)

    Busija, David W; Rutkai, Ibolya; Dutta, Somhrita; Katakam, Prasad V

    2016-06-13

    Mitochondria not only produce energy in the form of ATP to support the activities of cells comprising the neurovascular unit, but mitochondrial events, such as depolarization and/or ROS release, also initiate signaling events which protect the endothelium and neurons against lethal stresses via pre-/postconditioning as well as promote changes in cerebral vascular tone. Mitochondrial depolarization in vascular smooth muscle (VSM), via pharmacological activation of the ATP-dependent potassium channels on the inner mitochondrial membrane (mitoKATP channels), leads to vasorelaxation through generation of calcium sparks by the sarcoplasmic reticulum and subsequent downstream signaling mechanisms. Increased release of ROS by mitochondria has similar effects. Relaxation of VSM can also be indirectly achieved via actions of nitric oxide (NO) and other vasoactive agents produced by endothelium, perivascular and parenchymal nerves, and astroglia following mitochondrial activation. Additionally, NO production following mitochondrial activation is involved in neuronal preconditioning. Cerebral arteries from female rats have greater mitochondrial mass and respiration and enhanced cerebral arterial dilation to mitochondrial activators. Preexisting chronic conditions such as insulin resistance and/or diabetes impair mitoKATP channel relaxation of cerebral arteries and preconditioning. Surprisingly, mitoKATP channel function after transient ischemia appears to be retained in the endothelium of large cerebral arteries despite generalized cerebral vascular dysfunction. Thus, mitochondrial mechanisms may represent the elusive signaling link between metabolic rate and blood flow as well as mediators of vascular change according to physiological status. Mitochondrial mechanisms are an important, but underutilized target for improving vascular function and decreasing brain injury in stroke patients. © 2016 American Physiological Society. Compr Physiol 6:1529-1548, 2016.

  16. Role of Mitochondria in Cerebral Vascular Function: Energy Production, Cellular Protection, and Regulation of Vascular Tone.

    Science.gov (United States)

    Busija, David W; Rutkai, Ibolya; Dutta, Somhrita; Katakam, Prasad V

    2016-01-01

    Mitochondria not only produce energy in the form of ATP to support the activities of cells comprising the neurovascular unit, but mitochondrial events, such as depolarization and/or ROS release, also initiate signaling events which protect the endothelium and neurons against lethal stresses via pre-/postconditioning as well as promote changes in cerebral vascular tone. Mitochondrial depolarization in vascular smooth muscle (VSM), via pharmacological activation of the ATP-dependent potassium channels on the inner mitochondrial membrane (mitoKATP channels), leads to vasorelaxation through generation of calcium sparks by the sarcoplasmic reticulum and subsequent downstream signaling mechanisms. Increased release of ROS by mitochondria has similar effects. Relaxation of VSM can also be indirectly achieved via actions of nitric oxide (NO) and other vasoactive agents produced by endothelium, perivascular and parenchymal nerves, and astroglia following mitochondrial activation. Additionally, NO production following mitochondrial activation is involved in neuronal preconditioning. Cerebral arteries from female rats have greater mitochondrial mass and respiration and enhanced cerebral arterial dilation to mitochondrial activators. Preexisting chronic conditions such as insulin resistance and/or diabetes impair mitoKATP channel relaxation of cerebral arteries and preconditioning. Surprisingly, mitoKATP channel function after transient ischemia appears to be retained in the endothelium of large cerebral arteries despite generalized cerebral vascular dysfunction. Thus, mitochondrial mechanisms may represent the elusive signaling link between metabolic rate and blood flow as well as mediators of vascular change according to physiological status. Mitochondrial mechanisms are an important, but underutilized target for improving vascular function and decreasing brain injury in stroke patients. © 2016 American Physiological Society. Compr Physiol 6:1529-1548, 2016. PMID:27347901

  17. Measurement of arterial compliance in vivo.

    Science.gov (United States)

    Wiinberg, N

    2000-01-01

    Measurement of arterial compliance is of interest in evaluating patients with atherosclerosis and other diseases which affect the vessels. Arterial compliance is the relation between changes in transmural pressure and volume of an arterial segment, where a high compliance signifies large changes in volume per change in transmural pressure. The relation between changes in transmural pressure and volume is far from linear as compliance increases progressively with decreases in blood pressure. A change in compliance could indicate static changes in arterial wall composition, i.e. the relation between elastic and collagen fibres and accumulation of disease related deposits or dynamic changes caused by alterations in muscular tone. The most used method reflecting arterial compliance is the measurement of pulse wave velocity. However, the pulse wave velocity method measures compliance at ambient transmural pressures and is affected both by the actual blood pressure and the rate of pressure change. Another commonly used method employs the echo-tracking technique to measure the arterial diameter simultaneously with continuous blood pressure monitoring. By this method it is possible to calculate arterial compliance for continuous pressure values between the diastole and the systole. The volume-oscillometry method is based on the fact that the artery can be made to collapse at the end of the diastole by an occlusive cuff while it remains open in a pressure dependent manner during the rest of the cardiac cycle. Changes in the arterial volume is transmitted to the cuff, where it induces a measurable change in pressure, and hence the volume of the artery can be calculated at different values of transmural pressures. Using this method on normal subjects has shown that the arterial compliance decreases with increasing age and that females have lower compliance than males primarily due to a smaller diameter of their arteries. It has also been shown that patients with essential

  18. Intermittent hypoxia in rats reduces activation of Ca2+ sparks in mesenteric arteries.

    Science.gov (United States)

    Jackson-Weaver, Olan; Osmond, Jessica M; Naik, Jay S; Gonzalez Bosc, Laura V; Walker, Benjimen R; Kanagy, Nancy L

    2015-12-01

    Ca(+) sparks are vascular smooth muscle cell (VSMC) Ca(2+)-release events that are mediated by ryanodine receptors (RyR) and promote vasodilation by activating large-conductance Ca(2+)-activated potassium channels and inhibiting myogenic tone. We have previously reported that exposing rats to intermittent hypoxia (IH) to simulate sleep apnea augments myogenic tone in mesenteric arteries through loss of hydrogen sulfide (H2S)-induced dilation. Because we also observed that H2S can increase Ca(2+) spark activity, we hypothesized that loss of H2S after IH exposure reduces Ca(2+) spark activity and that blocking Ca(2+) spark generation reduces H2S-induced dilation. Ca(2+) spark activity was lower in VSMC of arteries from IH compared with sham-exposed rats. Furthermore, depolarizing VSMC by increasing luminal pressure (from 20 to 100 mmHg) or by elevating extracellular [K(+)] increased spark activity in VSMC of arteries from sham rats but had no effect in arteries from IH rats. Inhibiting endogenous H2S production in sham arteries prevented these increases. NaHS or phosphodiesterase inhibition increased spark activity to the same extent in sham and IH arteries. Depolarization-induced increases in Ca(2+) spark activity were due to increased sparks per site, whereas H2S increases in spark activity were due to increased spark sites per cell. Finally, inhibiting Ca(2+) spark activity with ryanodine (10 μM) enhanced myogenic tone in arteries from sham but not IH rats and blocked dilation to exogenous H2S in arteries from both sham and IH rats. Our results suggest that H2S regulates RyR activation and that H2S-induced dilation requires Ca(2+) spark activation. IH exposure decreases endogenous H2S-dependent Ca(2+) spark activation to cause membrane depolarization and enhance myogenic tone in mesenteric arteries.

  19. Subgroup differences in the lexical tone mismatch negativity (MMN) among Mandarin speakers with congenital amusia.

    Science.gov (United States)

    Nan, Yun; Huang, Wan-ting; Wang, Wen-jing; Liu, Chang; Dong, Qi

    2016-01-01

    The association/dissociation of pitch processing between music and language is a long lasting debate. We examined this music-language relationship by investigating to what extent pitch deficits in these two domains were dissociable. We focused on a special neurodevelopmental pitch disorder - congenital amusia, which primarily affects musical pitch processing. Recent research has also revealed lexical tone deficits in speech among amusics. Approximately one-third of Mandarin amusics exhibits behavioural difficulties in lexical tone perception, which is known as tone agnosia. Using mismatch negativities (MMNs), our current work probed lexical tone encoding at the pre-attentive level among the Mandarin amusics with (tone agnosics) and without (pure amusics) behavioural lexical tone deficits compared with age- and IQ-matched controls. Relative to the controls and the pure amusics, the tone agnosics exhibited reduced MMNs specifically in response to lexical tone changes. Their tone-consonant MMNs were intact and similar to those of the other two groups. Moreover, the tone MMN reduction over the left hemisphere was tightly linked to behavioural insensitivity to lexical tone changes. The current study thus provides the first psychophysiological evidence of subgroup differences in lexical tone processing among Mandarin amusics and links amusics' behavioural tone deficits to impaired pre-attentive tone processing. Despite the overall music pitch deficits, the subgroup differences in lexical tone processing in Mandarin-speaking amusics suggest dissociation of pitch deficits between music and speech. PMID:26638759

  20. Measurement of intraindividual airway tone heterogeneity and its importance in asthma.

    Science.gov (United States)

    Brown, Robert H; Togias, Alkis

    2016-07-01

    While airways have some degree of baseline tone, the level and variability of this tone is not known. It is also unclear whether there is a difference in airway tone or in the variability of airway tone between asthmatic and healthy individuals. This study examined airway tone and intraindividual airway tone heterogeneity (variance of airway tone) in vivo in 19 individuals with asthma compared with 9 healthy adults. All participants underwent spirometry, body plethysmography, and high-resolution computed tomography at baseline and after maximum bronchodilation with albuterol. Airway tone was defined as the percent difference in airway diameter after albuterol at total lung capacity compared with baseline. The amount of airway tone in each airway varied both within and between subjects. The average airway tone did not differ significantly between the two groups (P = 0.09), but the intraindividual airway tone heterogeneity did (P = 0.016). Intraindividual airway tone heterogeneity was strongly correlated with airway tone (r = 0.78, P < 0.0001). Also, it was negatively correlated with the magnitude of the distension of the airways from functional residual capacity to total lung capacity at both baseline (r = -0.49, P = 0.03) and after maximum bronchodilation (r = -0.51, P = 0.02) in the asthma, but not the healthy group. However, we did not find any relationship between intraindividual airway tone heterogeneity and conventional lung function outcomes. Intraindividual airway tone heterogeneity appears to be an important characteristic of airway pathophysiology in asthma. PMID:27103654

  1. Evaluation of HEXORR Tone Assistance Mode Against Spring Assistance.

    Science.gov (United States)

    Godfrey, Sasha Blue; Holley, Rahsaan J; Lum, Peter S

    2015-07-01

    Robots are a promising tool for rehabilitation, and research suggests combining assistance with subject participation to maintain motivation and engagement. In this study, we compare two different types of robotic assistance for hand rehabilitation: Tone, a novel method designed to directly compensate for the user's hypertonia, and Spring, a commonly used method simulating a spring-like force attracting the subject to the target position. Eight chronic stroke subjects played a Gate Game, where they guide a ball through a sweeping, on-screen gate. Each subject was exposed to 5 modes: unassisted, assisted by the Spring and Tone modes, and "delay" modes where the assistance was provided after a period without assistance. Compared to unassisted trials, subjects produced less positive work and more negative work with all types of assistance but also reached a larger ROM and scored higher on the game. Notably, subjects produced more positive work overall with Tone compared to Spring. Further, subjects produced positive work over a significantly shorter range with Spring compared to Unassisted, while there was no difference between Tone and Unassisted. While both modes were effective at enabling the training of a larger workspace, these results suggest Tone assistance maintains a greater level of subject engagement and participation, likely making it a useful tool for hand rehabilitation. PMID:25667355

  2. Turbo-per-Tone Equalization for ADSL Systems

    Directory of Open Access Journals (Sweden)

    Marc Moonen

    2005-05-01

    Full Text Available We study the equalization procedure in discrete multitone (DMT-based systems, in particular, in DMT-based ADSL systems. Traditionally, equalization is performed in the time domain by means of a channel shortening filter. Shifting the equalization operations to the frequency domain, as is done in per-tone equalization, increases the achieved bitrate by 5–10%. We show that the application of the turbo principle to per-tone equalization can provide significant additional gains. In the proposed receiver structure, referred to as a “turbo-per-tone equalization” structure, equalization and decoding are performed in an iterative fashion. Equalization is done by means of a linear minimum mean squared error (MMSE equalizer, using a priori information. We give a description of an efficient implementation of such an equalizer in the per-tone structure. Simulations show that we obtain a bitrate increase of 12–16% compared to the original per-tone equalization-based receiver structure.

  3. SBS mitigation with 'two-tone' amplification: a theoretical model

    Science.gov (United States)

    Bronder, T. J.; Shay, T. M.; Dajani, I.; Gavrielides, A.; Robin, C. A.; Lu, C. A.

    2008-02-01

    A new technique for mitigating stimulated Brillouin scattering (SBS) effects in narrow-linewidth Yb-doped fiber amplifiers is demonstrated with a model that reduces to solving an 8×8 system of coupled nonlinear equations with the gain, SBS, and four-wave mixing (FMW) incorporated into the model. This technique uses two seed signals, or 'two-tones', with each tone reaching its SBS threshold almost independently and thus increasing the overall threshold for SBS in the fiber amplifier. The wavelength separation of these signals is also selected to avoid FWM, which in this case possesses the next lowest nonlinear effects threshold. This model predicts an output power increase of 86% (at SBS threshold with no signs of FWM) for a 'two-tone' amplifier with seed signals at 1064nm and 1068nm, compared to a conventional fiber amplifier with a single 1064nm seed. The model is also used to simulate an SBS-suppressing fiber amplifier to test the regime where FWM is the limiting factor. In this case, an optimum wavelength separation of 3nm to 10nm prevents FWM from reaching threshold. The optimum ratio of the input power for the two seed signals in 'two-tone' amplification is also tested. Future experimental verification of this 'two-tone' technique is discussed.

  4. Mandarin Chinese Tone Recognition with an Artificial Neural Network

    Institute of Scientific and Technical Information of China (English)

    XU Li; ZHANG Wenle; ZHOU Ning; LEE Chaoyang; LI Yongxin; CHEN Xiuwu; ZHAO Xiaoyan

    2006-01-01

    Mandarin Chinese tone patterns vary in one of the four ways, i.e, (1) high level; (2) rising; (3) low falling and rising; and (4) high falling. The present study is to examine the efficacy of an artificial neural network in recognizing these tone patterns. Speech data were recorded from 12 children (3-6 years of age) and 15 adults. All subjects were native Mandarin Chinese speakers. The fundamental frequencies (FO) of each monosyllabic word of the speech data were extracted with an autocorrelation method. The pitch data(i.e., the FO contours) were the inputs to a feed-forward backpropagation artificial neural network. The number of inputs to the neural network varied from 1 to 16 and the hidden layer of the network contained neurons that varied from 1 to 16 in number. The output of the network consisted of four neurons representing the four tone patterns of Mandarin Chinese. After being trained with the Levenberg-Marquardt optimization, the neural network was able to successfully classify the tone patterns with an accuracy of about 90% correct for speech samples from both adults and children. The artificial neural network may provide an objective and effective way of assessing tone production in prelingually-deafened children who have received cochlear implants.

  5. Carotid Artery Screening

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Carotid Artery Screening What is carotid artery screening? Who should consider ... about carotid artery screening? What is carotid artery screening? Screening examinations are tests performed to find disease ...

  6. Effet de taille sur la capacité portante des fondations superficielles

    OpenAIRE

    Garnier, J.

    2003-01-01

    Il y a plus d'un demi siècle que les premières preuves expérimentales de l'effet de la taille sur la portance des fondations ont été apportées et des données nouvelles sont régulièrement produites. De nombreuses théories ont été avancées pour rendre compte de cet effet. Elles sont présentées et comparées dans cet article et des conclusions sont tirées tant pour la prévision de la portance des fondations que pour la conduite d'essais sur ouvrages en semi-grandeur ou sur modèles réduits. Siz...

  7. Les émissions de CO2 et autres gaz à effets de serre

    OpenAIRE

    François Durand-Dastès

    2010-01-01

    Cette note envisage les composantes explicatives des émissions de Gaz à effet de serre : coefficient d’émission par habitant et par unité monétaire de PNB, effets des masses de population et de production. La part de ces derniers est parfois curieusement sous estimée dans la littérature, et il semble nécessaire d’insister sur leur rôle majeur. Après une présentation cartographique et graphique de quelques données essentielles, on se livre à une expérimentation prospective à partir de ces donn...

  8. The Theory of Adaptive Dispersion and Acoustic-phonetic Properties of Cross-language Lexical-tone Systems

    Science.gov (United States)

    Alexander, Jennifer Alexandra

    Lexical-tone languages use fundamental frequency (F0/pitch) to convey word meaning. About 41.8% of the world's languages use lexical tone (Maddieson, 2008), yet those systems are under-studied. I aim to increase our understanding of speech-sound inventory organization by extending to tone-systems a model of vowel-system organization, the Theory of Adaptive Dispersion (TAD) (Liljencrants and Lindblom, 1972). This is a cross-language investigation of whether and how the size of a tonal inventory affects (A) acoustic tone-space size and (B) dispersion of tone categories within the tone-space. I compared five languages with very different tone inventories: Cantonese (3 contour, 3 level tones); Mandarin (3 contour, 1 level tone); Thai (2 contour, 3 level tones); Yoruba (3 level tones only); and Igbo (2 level tones only). Six native speakers (3 female) of each language produced 18 CV syllables in isolation, with each of his/her language's tones, six times. I measured tonal F0 across the vowel at onset, midpoint, and offglide. Tone-space size was the F0 difference in semitones (ST) between each language's highest and lowest tones. Tone dispersion was the F0 distance (ST) between two tones shared by multiple languages. Following the TAD, I predicted that languages with larger tone inventories would have larger tone-spaces. Against expectations, tone-space size was fixed across level-tone languages at midpoint and offglide, and across contour-tone languages (except Thai) at offglide. However, within each language type (level-tone vs. contour-tone), languages with smaller tone inventories had larger tone spaces at onset. Tone-dispersion results were also unexpected. The Cantonese mid-level tone was further dispersed from a tonal baseline than the Yoruba mid-level tone; Cantonese mid-level tone dispersion was therefore greater than theoretically necessary. The Cantonese high-level tone was also further dispersed from baseline than the Mandarin high-level tone -- at midpoint

  9. Des effets du divorce et du non divorce sur les enfants

    OpenAIRE

    Martin, Claude

    2007-01-01

    The issue of divorce and its effets on children has repeatedly been raised since the 18th century. This article synthesize the main findings of current international reserach and condider the effects of non-divorcing for couples who fall out of love and experience conflict. What happens to couples who decide not to divorce for the children's sake. What about the live together apart couples? Cet article propose de revenir sur les principales conclusions des recherches internationales sur le...

  10. On the origin of impinging tones at low supersonic flow

    CERN Document Server

    Wilke, Robert

    2016-01-01

    Impinging compressible jets may cause deafness and material fatigue due to immensely loud tonal noise. It is generally accepted that a feedback mechanism similar to the screech feedback loop is responsible for impinging tones. The close of the loop remained unclear. One hypothesis hold up in the literature explains the emanated sound with the direct interaction of vortices and the wall. Other explanations name the standoff shock oscillations as the origin of the tones. Using direct numerical simulations (DNS) we were able to identify the source mechanism for under-expanded impinging jets with a nozzle pressure ratio (NPR) of 2.15 and a plate distance of 5 diameters. We found two different types of interactions between vortices and shocks to be responsible for the generation of the impinging tones. They are not related to screech.

  11. Complex-tone pitch representations in the human auditory system

    DEFF Research Database (Denmark)

    Bianchi, Federica

    ) listeners and the effect of musical training for pitch discrimination of complex tones with resolved and unresolved harmonics. Concerning the first topic, behavioral and modeling results in listeners with sensorineural hearing loss (SNHL) indicated that temporal envelope cues of complex tones......Understanding how the human auditory system processes the physical properties of an acoustical stimulus to give rise to a pitch percept is a fascinating aspect of hearing research. Since most natural sounds are harmonic complex tones, this work focused on the nature of pitch-relevant cues...... that are necessary for the auditory system to retrieve the pitch of complex sounds. The existence of different pitch-coding mechanisms for low-numbered (spectrally resolved) and high-numbered (unresolved) harmonics was investigated by comparing pitch-discrimination performance across different cohorts of listeners...

  12. The effect of a cavity on airfoil tones

    Science.gov (United States)

    Schumacher, Karn L.; Doolan, Con J.; Kelso, Richard M.

    2014-03-01

    The presence of a cavity in the pressure surface of an airfoil has been found via experiment to play a role in the production of airfoil tones, which was attributed to the presence of an acoustic feedback loop. The cavity length was sufficiently small that cavity oscillation modes did not occur for most of the investigated chord-based Reynolds number range of 70,000-320,000. The airfoil tonal noise frequencies varied as the position of the cavity was moved along a parallel section at the airfoil's maximum thickness: specifically, for a given velocity, the frequency spacing of the tones was inversely proportional to the geometric distance between the cavity and the trailing edge. The boundary layer instability waves considered responsible for the airfoil tones were only detected downstream of the cavity. This may be the first experimental verification of these aspects of the feedback loop model for airfoil tonal noise.

  13. Player Collaboration in the Explorative Sound Environment ToneInk

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa

    2016-01-01

    In the present paper, ToneInk, a prototype of a music based play scenario that investigates player collaboration, is introduced. ToneInk is an explorative sound environment that differs from the majority of music based games in that players can collaborate and be creative in the way they express...... themselves through melody and rhythm. The paper provides player interaction and navigation results and demonstrates how various affordances in the ToneInk design iterations make it hard or possible for players to engage with the system and with each other. From observations it was clear that players lost...... mutual awareness, and in general were more passive when they needed to monitor a screen interface that supported the sound environment. Player collaboration was strongest when players negotiated rhythm, while the negotiation of melody was temporally offset and consisted of long individual explorations....

  14. Phonology in the Lexical Processing of Chinese: Priming Tone Neighbors

    Institute of Scientific and Technical Information of China (English)

    Zhou Xiaolin

    2000-01-01

    Using both visual-visual and auditory-visual priming lexical decision tasks, this study investigated phonological processing in reading logographic Chinese. Compound words sharing segmental templates but differing in lexical tones were used as primes and targets while their relative frequency was manipulated. It was found that tone neighbours did not prime each other significantly and the SOA of 100 msec in visual-visual priming. When the SOA was increased to 357 msec, or when primes were presented auditorily, the processing of target words was significantly delayed by their tone neighbours. Larger inhibitory effects were observed for low frequency targets with high frequency primes. It was argued that although phonological information is automatically activated and this activation affects access to semantics in reading Chinese,phonological mediation is not the only or the main ~urce of constraints on semantic activation.

  15. The influence of pipe organ reed curvature on tone quality.

    Science.gov (United States)

    Plitnik, George R; Angster, Judit

    2012-11-01

    Although organ flue pipes have been widely studied, the same claim cannot be made for pipe organ reed stops. Given certain design constraints, such as the type of reed stop being voiced and the desired tone quality, the reed voicer must use consummate skill to curve the reed tongue so as to produce the best and most stable tone as well as to guarantee that each pipe blends with its neighbors. The amount and type of curve given to a reed tongue influences not only the harmonic structure of the steady-state sound but also the attack. There are two fundamentally different types of curvature that can be given to a reed tongue, the trompette (chorus reed) curve (which gives a bright sound) and the smooth-toned curve employed for clarinet pipes. This study investigated the effect of reed curvature on the vibration and tone (as assessed by professionals) on reed tongues of both types. Two F2 (8'F, 87.3 Hz) pipes (a trompette and a clarinet) were constructed and voiced with differently curved tongues to produce a variety of tones. The vibration of the reed tongue was measured under typical conditions by laser vibrometer; the pressure waves in the boot and in the shallot were measured by means of one-quarter inch microphones, and the pipe's sound was recorded at the egress. By performing various measurements simultaneously, phase differences were also determined, the extreme sensitivity of tone to reed curvature was demonstrated, and a recently proposed theory of reed vibration was shown to be more accurate than the standard model. PMID:23145630

  16. Myogenic constriction is increased in mesenteric resistance arteries from rats with chronic heart failure : instantaneous counteraction by acute AT(1) receptor blockade

    NARCIS (Netherlands)

    Gschwend, S; Henning, RH; Pinto, YM; de Zeeuw, D; van Gilst, WH; Buikema, H

    2003-01-01

    1 Increased vascular resistance in chronic heart failure (CHF) has been attributed to stimulated neurohumoral systems. However, local mechanisms may also importantly contribute to set arterial tone. Our aim, therefore, was to test whether pressure-induced myogenic constriction of resistance arteries

  17. Positive Feedback Regulation of Agonist-Stimulated Endothelial Ca2+ Dynamics by KCa3.1 Channels in Mouse Mesenteric Arteries

    DEFF Research Database (Denmark)

    Qian, Xun; Francis, Michael; Köhler, Ralf;

    2014-01-01

    Intermediate and small conductance KCa channels IK1 (KCa3.1) and SK3 (KCa2.3) are primary targets of endothelial Ca(2+) signals in the arterial vasculature, and their ablation results in increased arterial tone and hypertension. Activation of IK1 channels by local Ca(2+) transients from internal ...

  18. Fan Noise Source Diagnostic Test: Tone Modal Structure Results

    Science.gov (United States)

    Heidelberg, Laurence J.

    2002-01-01

    This investigation is part of a test series that was extremely comprehensive and included aerodynamic and acoustic testing of a fan stage using two different fan rotors and three different stator designs. The test series is known as the Source Diagnostic Test (SDT) and was conducted by NASA Glenn as part of the Advanced Subsonic Technology (AST) Noise Reduction Program. Tone mode measurements of one of the rotors with three different stators were made. The stator designs involve changes in vane count and sweep at constant solidity. The results of both inlet and exhaust tone mode measurements are presented in terms of mode power for both circumferential and radial mode orders. The results show benefits of vane sweep to be large, up to 13 dB in total tone power. At many conditions, the increase in power due to cutting on the rotor/stator interaction is more than offset by vane sweep. The rotor locked mode is shown as an important contributor to tone power when the blade tip speed is near and above Mach one. This is most evident in the inlet when the direct rotor field starts to cut on.

  19. The correlated track receiver of tone track circuits

    OpenAIRE

    Goncharov, K. V.

    2011-01-01

    The work is devoted to further improvement of processing algorithm of checking signals of rail line. The simulation modeling of correlation track receiver of tone rail circuits has been executed; the benchmark analysis of correlation receiver and direct amplifier receiver has been executed.

  20. THE CORRELATED TRACK RECEIVER OF TONE TRACK CIRCUITS

    Directory of Open Access Journals (Sweden)

    K. V. Goncharov

    2011-05-01

    Full Text Available The work is devoted to further improvement of processing algorithm of checking signals of rail line. The simulation modeling of correlation track receiver of tone rail circuits has been executed; the benchmark analysis of correlation receiver and direct amplifier receiver has been executed.

  1. Consonance perception of complex-tone dyads and chords

    DEFF Research Database (Denmark)

    Rasmussen, Marc; Santurette, Sébastien; MacDonald, Ewen

    2014-01-01

    Sensory consonance and dissonance are perceptual attributes of musical intervals conveying pleasant- ness, tension, and harmony in musical phrases. For complex-tone dyads, corresponding to two musical notes played simultaneously, consonance is known to vary with the ratio in fundamental frequency...... for a potential role of frequency selectivity for consonance perception of dyads, might not hold for chords...

  2. Computer Pure-Tone and Operator Stress: Report III.

    Science.gov (United States)

    Dow, Caroline; Covert, Douglas C.

    Pure-tone sound at 15,750 Herz generated by flyback transformers in many computer and video display terminal (VDT) monitors has stress-related productivity effects in some operators, especially women. College-age women in a controlled experiment simulating half a normal work day showed responses within the first half hour of exposure to a tone…

  3. Studying Tones in North East India: Tai, Singpho and Tangsa

    Science.gov (United States)

    Morey, Stephen

    2014-01-01

    Drawing on nearly 20 years of study of a variety of languages in North East India, from the Tai and Tibeto-Burman families, this paper examines the issues involved in studying those languages, building on three well established principles: (a) tones are categories within a language, and the recognition of those categories is the key step in…

  4. Increased resting bronchial tone in normal subjects acclimatised to altitude

    OpenAIRE

    Wilson, C.; Bakewell, S; M. Miller; Hart, N; McMorrow, R; BARRY, P.; Collier, D; Watt, S; Pollard, A.

    2002-01-01

    Background: Normal subjects frequently experience troublesome respiratory symptoms when acclimatised to altitude. Bronchial hyperresponsiveness (BHR) and full and partial flow-volume loops were measured before and after ascent to 5000 m altitude to determine if there are changes in resting bronchial tone and BHR that might explain the symptoms.

  5. Short and long term representation of an unfamiliar tone distribution.

    Science.gov (United States)

    Cui, Anja X; Diercks, Charlette; Troje, Nikolaus F; Cuddy, Lola L

    2016-01-01

    We report on a study conducted to extend our knowledge about the process of gaining a mental representation of music. Several studies, inspired by research on the statistical learning of language, have investigated statistical learning of sequential rules underlying tone sequences. Given that the mental representation of music correlates with distributional properties of music, we tested whether participants are able to abstract distributional information contained in tone sequences to form a mental representation. For this purpose, we created an unfamiliar music genre defined by an underlying tone distribution, to which 40 participants were exposed. Our stimuli allowed us to differentiate between sensitivity to the distributional properties contained in test stimuli and long term representation of the distributional properties of the music genre overall. Using a probe tone paradigm and a two-alternative forced choice discrimination task, we show that listeners are able to abstract distributional properties of music through mere exposure into a long term representation of music. This lends support to the idea that statistical learning is involved in the process of gaining musical knowledge. PMID:27635355

  6. Context, Contrast, and Tone of Voice in Auditory Sarcasm Perception

    Science.gov (United States)

    Voyer, Daniel; Thibodeau, Sophie-Hélène; Delong, Breanna J.

    2016-01-01

    Four experiments were conducted to investigate the interplay between context and tone of voice in the perception of sarcasm. These experiments emphasized the role of contrast effects in sarcasm perception exclusively by means of auditory stimuli whereas most past research has relied on written material. In all experiments, a positive or negative…

  7. The Role of Tone in Some Cushitic Languages.

    Science.gov (United States)

    Appleyard, David L.

    1991-01-01

    The morphological function of tone/accent is examined in a number of Cushitic languages, with the objective of determining whether any comparative statement can be made validly at the group level. Three languages, the Somali dialect cluster, Afar, and Oromo, are the basis for the study. Patterns in case, gender, and the jussive form are analyzed.…

  8. Potassium channels in pulmonary arterial hypertension.

    Science.gov (United States)

    Boucherat, Olivier; Chabot, Sophie; Antigny, Fabrice; Perros, Frédéric; Provencher, Steeve; Bonnet, Sébastien

    2015-10-01

    Pulmonary arterial hypertension (PAH) is a devastating cardiopulmonary disorder with various origins. All forms of PAH share a common pulmonary arteriopathy characterised by vasoconstriction, remodelling of the pre-capillary pulmonary vessel wall, and in situ thrombosis. Although the pathogenesis of PAH is recognised as a complex and multifactorial process, there is growing evidence that potassium channels dysfunction in pulmonary artery smooth muscle cells is a hallmark of PAH. Besides regulating many physiological functions, reduced potassium channels expression and/or activity have significant effects on PAH establishment and progression. This review describes the molecular mechanisms and physiological consequences of potassium channel modulation. Special emphasis is placed on KCNA5 (Kv1.5) and KCNK3 (TASK1), which are considered to play a central role in determining pulmonary vascular tone and may represent attractive therapeutic targets in the treatment of PAH. PMID:26341985

  9. Woodwind Tone Hole Acoustics and the Spectrum Transformation Function.

    Science.gov (United States)

    Keefe, Douglas Howard

    This report describes an investigation of woodwind musical instrument tone holes and their effect on the radiated spectrum, the total dissipation, the stability of oscillation, the psychoacoustical cues important in perception, and the tuning and response of the instrument. Varying tone hole proportions significantly affect the radiative and frictional damping near a single hole, the mutual interactions between holes, the onset of streaming and turbulence near the holes, and the perceived woodwind timbre. The interconnections between related fields are explored through a brief review of sound production in woodwinds plus more extensive reviews of room and psychological acoustics. A theoretical and experimental discussion of the spectrum transformation function from the mouthpiece into the room relates all these fields. Also, considered are differences between cylindrical and conical bore woodwinds, the systematic shifts in saxophone spectra produced by the beating of the reed, the coupling of many closely spaced tone holes to the room excitation, the role of the player, and the results pertaining to computer music synthesis. The complicated acoustical flow inside the main air column near a single tone hole has been examined using a Green function, integral equation approach. A variational formulation allows explicit calculation of the open and closed hole impedance parameters needed in the transmission line description of a woodwind, and experiments have verified the theory in detail. Major acoustical topics considered are listed below. The effective length t(,e) of an open hole, relevant for instrument design and modification, is calculated and measured in terms of the main bore diameter 2a, hole diameter 2b, and the height t of the hole chimney; the effect of a hanging pad is a semi-empirical correction on t(,e). When the fundamental plane-wave mode of the main air column oscillation is at a pressure node, both the open and closed hole series impedances are

  10. Implicit target substitution and sequencing for lexical tone production in Chinese: an FMRI study.

    Science.gov (United States)

    Chang, Hui-Chuan; Lee, Hsin-Ju; Tzeng, Ovid J L; Kuo, Wen-Jui

    2014-01-01

    In this study, we examine the neural substrates underlying Tone 3 sandhi and tone sequencing in Mandarin Chinese using fMRI. Tone 3 sandhi is traditionally described as the substitution of Tone 3 with Tone 2 when followed by another Tone 3 (i.e., 33→23). According to current speech production models, target substitution is expected to engage the posterior inferior frontal gyrus. Since Tone 3 sandhi is, to some extent, independent of segments, which makes it more similar to singing, right-lateralized activation in this region was predicted. As for tone sequencing, based on studies in sequencing, we expected the involvement of the supplementary motor area. In the experiments, participants were asked to produce twelve four-syllable sequences with the same tone assignment (the repeated sequences) or a different tone assignment (the mixed sequences). We found right-lateralized posterior inferior frontal gyrus activation for the sequence 3333 (Tone 3 sandhi) and left-lateralized activation in the supplementary motor area for the mixed sequences (tone sequencing). We proposed that tones and segments could be processed in parallel in the left and right hemispheres, but their integration, or the product of their integration, is hosted in the left hemisphere.

  11. Implicit target substitution and sequencing for lexical tone production in Chinese: an FMRI study.

    Directory of Open Access Journals (Sweden)

    Hui-Chuan Chang

    Full Text Available In this study, we examine the neural substrates underlying Tone 3 sandhi and tone sequencing in Mandarin Chinese using fMRI. Tone 3 sandhi is traditionally described as the substitution of Tone 3 with Tone 2 when followed by another Tone 3 (i.e., 33→23. According to current speech production models, target substitution is expected to engage the posterior inferior frontal gyrus. Since Tone 3 sandhi is, to some extent, independent of segments, which makes it more similar to singing, right-lateralized activation in this region was predicted. As for tone sequencing, based on studies in sequencing, we expected the involvement of the supplementary motor area. In the experiments, participants were asked to produce twelve four-syllable sequences with the same tone assignment (the repeated sequences or a different tone assignment (the mixed sequences. We found right-lateralized posterior inferior frontal gyrus activation for the sequence 3333 (Tone 3 sandhi and left-lateralized activation in the supplementary motor area for the mixed sequences (tone sequencing. We proposed that tones and segments could be processed in parallel in the left and right hemispheres, but their integration, or the product of their integration, is hosted in the left hemisphere.

  12. Perceptual evidence for protracted development in monosyllabic Mandarin lexical tone production in preschool children in Taiwan.

    Science.gov (United States)

    Wong, Puisan

    2013-01-01

    This study used the same methodology in Wong [J. Speech Lang. Hear. Res. 55, 1423-1437 (2012b)] to examine the perceived accuracy of monosyllabic Mandarin tones produced by 4- and 5-year-old Mandarin-speaking children growing up in Taiwan and combined the findings with those of 3-year-olds reported in Wong [J. Speech Lang. Hear. Res. 55, 1423-1437 (2012b)] to track the development of monosyllabic tone production in preschool children. Tone productions of adults and children were collected in a picture naming task and low-pass filtered to remove lexical information and reserve tone information. Five native-speakers categorized the target tones in the filtered productions. Children's tone accuracy was compared to adults' to determine mastery and developmental changes. The results showed that preschool children in Taiwan have not fully mastered the production of monosyllabic Mandarin tones. None of the tones produced by the children in the three age groups reached adult-like accuracy. Little developmental change was found in children's tone accuracy during the preschool years. A similar order of accuracy of the tones was observed across the three age groups and the order appeared to follow the order of articulatory complexity in producing the tones. The findings suggest a protracted course of development in children's acquisition of Mandarin tones and that tone development may be constrained by physiological factors.

  13. The prosody of Swedish underived nouns: No lexical tones required

    Directory of Open Access Journals (Sweden)

    Bruce Morén-Duolljá

    2013-02-01

    Full Text Available Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} This paper provides a detailed representational analysis of the morpho-prosodic system of underived nouns in a dialect of Swedish.  It shows that the morphology, stress and tonal patterns are not as complex as they first appear once the data are looked at in sufficient detail.  Further, it shows that the renowned Swedish "lexical pitch accent" is not the result of lexical tones/tonemes.  Rather, Swedish is like all other languages and uses tones to mark the edges of prosodic constituents on the surface. "Accent 2" occurs when tones mark the edge of a structural uneven trochee (i.e. recursive foot and "accent 1" occurs elsewhere. This analysis is counter all other treatments of North Germanic tones and denies the almost unquestioned assumption that there is an underlying tone specification on roots and/or affixes in many North Germanic varieties. At the same time, it unifies the intuitions behind the three previous approaches found in the literature.

  14. Effects of production training and perception training on lexical tone perception--A behavioral and ERP study.

    Science.gov (United States)

    Lu, Shuang; Wayland, Ratree; Kaan, Edith

    2015-10-22

    The present study recorded both behavioral data and event-related brain potentials to examine the effectiveness of a perception-only training and a perception-plus-production training procedure on the intentional and unintentional perception of lexical tone by native English listeners. In the behavioral task, both the perception-only and the perception-plus-production groups improved on the tone discrimination abilities after the training session. Moreover, the participants in both groups generalized the improvements gained through the trained stimuli to the untrained stimuli. In the ERP task, the Mismatch Negativity was smaller in the post-training task than in the pre-training task. However, the two training groups did not differ in tone processing at the intentional or unintentional level after training. These results suggest that the employment of the motor system does not specifically benefit the tone perceptual skills. Furthermore, the present study investigated whether some tone pairs are more easily confused than others by native English listeners, and whether the order of tone presentation influences non-native tone discrimination. In the behavioral task, Tone2-Tone1 (rising-level) and Tone2-Tone4 (rising-falling) were the most difficult tone pairs, while Tone1-Tone2 and Tone4-Tone2 were the easiest tone pairs, even though they involved the same tone contrasts respectively. In the ERP task, the native English listeners had good discrimination when Tone2 and Tone4 were embedded in strings of Tone1, while poor discrimination when Tone1 was inserted in the context of Tone2 or Tone4. These asymmetries in tone perception might be attributed to the interference of native intonation system and can be altered by training.

  15. Effects of production training and perception training on lexical tone perception--A behavioral and ERP study.

    Science.gov (United States)

    Lu, Shuang; Wayland, Ratree; Kaan, Edith

    2015-10-22

    The present study recorded both behavioral data and event-related brain potentials to examine the effectiveness of a perception-only training and a perception-plus-production training procedure on the intentional and unintentional perception of lexical tone by native English listeners. In the behavioral task, both the perception-only and the perception-plus-production groups improved on the tone discrimination abilities after the training session. Moreover, the participants in both groups generalized the improvements gained through the trained stimuli to the untrained stimuli. In the ERP task, the Mismatch Negativity was smaller in the post-training task than in the pre-training task. However, the two training groups did not differ in tone processing at the intentional or unintentional level after training. These results suggest that the employment of the motor system does not specifically benefit the tone perceptual skills. Furthermore, the present study investigated whether some tone pairs are more easily confused than others by native English listeners, and whether the order of tone presentation influences non-native tone discrimination. In the behavioral task, Tone2-Tone1 (rising-level) and Tone2-Tone4 (rising-falling) were the most difficult tone pairs, while Tone1-Tone2 and Tone4-Tone2 were the easiest tone pairs, even though they involved the same tone contrasts respectively. In the ERP task, the native English listeners had good discrimination when Tone2 and Tone4 were embedded in strings of Tone1, while poor discrimination when Tone1 was inserted in the context of Tone2 or Tone4. These asymmetries in tone perception might be attributed to the interference of native intonation system and can be altered by training. PMID:26206301

  16. "Mirror, mirror...." a preliminary investigation of skin tone dissatisfaction and its impact among British adults.

    Science.gov (United States)

    Swami, Viren; Henry, Amy; Peacock, Nicola; Roberts-Dunn, Ahkin; Porter, Alan

    2013-10-01

    This study examined skin tone dissatisfaction, measured using a skin tone chart, among a multiethnic sample of British adults. A total of 648 British White individuals, 292 British South Asians, and 260 British African Caribbean participants completed a visual task in which they were asked to indicate their actual and ideal skin tones. They also completed measures of body appreciation, self-esteem, and ethnic identity attachment. Results showed that Asians had a lighter skin tone ideal than White and African Caribbean participants. Conversely, White participants had higher skin tone dissatisfaction (preferring a darker skin tone) than Asian and African Caribbean participants, who preferred a lighter skin tone. Results also showed that skin tone dissatisfaction predicted body appreciation once the effects of participant ethnicity, age, ethnic identity attachment, and self-esteem had been accounted for. Implications of our findings and suggestions for future research are discussed.

  17. Angioplasty and stent placement -- peripheral arteries

    Science.gov (United States)

    Percutaneous transluminal angioplasty - peripheral artery; PTA - peripheral artery; Angioplasty - peripheral arteries; Iliac artery -angioplasty; Femoral artery - angioplasty; Popliteal artery - angioplasty; Tibial ...

  18. Normalization of muscle tone in children with cerebral palsy in special schools.

    Directory of Open Access Journals (Sweden)

    Kruglyak M.

    2011-08-01

    Full Text Available The features of using exercise to reduce muscle tone in children with cerebral palsy in training at a special school. The study involved children with cerebral palsy 7-10 years. Presents the results of evaluation of motor function and muscle tone. The efficacy of the use of physical rehabilitation for children with cerebral palsy, a positive effect of using special exercise in stretching the muscles with increased tone, improve motor function and normalization of muscle tone.

  19. Perception and Production of Lexical Tones by 3-Year-Old, Mandarin-Speaking Children

    Science.gov (United States)

    Wong, Puisan; Schwartz, Richard G.; Jenkins, James J.

    2005-01-01

    The present study investigated 3-year-old children's perception and production of Mandarin lexical tones in monosyllabic words. Thirteen 3-year-old, Mandarin-speaking children participated in the study. Tone perception was examined by a picture-pointing task, and tone production was investigated by picture naming. To compare children's productions…

  20. Analytical Solution and Numerical Simulation of Real-Time Dispersion Monitoring Using Tone Subcarrier

    Institute of Scientific and Technical Information of China (English)

    HUANG He; CHEN Fushen; JIANG Yi

    2003-01-01

    A method for online dispersion monitoring by adding a single in-band subcarrier tone is introduced. According to the theoretical analysis, the dispersion monitor and measurement range are determined by the specific frequency of the subcarrier tone. By using simulation tools, figures about relationship between power of subcarrier tone and transmission distance in ideal condition are shown.

  1. Perceived Pitch of Violin and Cello Vibrato Tones among Music Majors

    Science.gov (United States)

    Geringer, John M.; MacLeod, Rebecca B.; Allen, Michael L.

    2010-01-01

    The purpose of this study was to investigate the perceived pitch of string vibrato tones. The authors used recordings of acoustic instruments (cello and violin) to provide both vibrato stimulus tones and the nonvibrato tones that listeners adjusted to match the perceived pitch of the vibrato stimuli. We were interested especially in whether there…

  2. An Annotated Bibliography on Tone. UCLA Working Papers in Phonetics 28.

    Science.gov (United States)

    Maddieson, Ian, Comp.; Gandour, Jack, Comp.

    This annotated bibliography, which has been entered into the SOLAR Bibliography File, focuses on the phonetics and phonology of tone, including studies on the physiology of phonation and pitch control, pitch perception, inherent pitch of vowels, the interaction of tone with musical melody in tone languages, and other related issues. An attempt has…

  3. Colorism in the Classroom: How Skin Tone Stratifies African American and Latina/o Students

    Science.gov (United States)

    Hunter, Margaret

    2016-01-01

    Although racial inequality is frequently studied in education, skin tone stratification has received less attention from educational researchers. Inequality by skin tone, also known as "colorism", contributes to larger patterns of racial inequality for African Americans and Latina/os. Discrimination by skin tone affects many dimensions…

  4. The Tonology of Itoman Okinawan: A Phonological Analysis of the Nominal Tone System

    Science.gov (United States)

    Takara, Nobutaka

    2012-01-01

    Itoman, one of the varieties spoken in the southern part of Okinawa Island, exhibits several tone patterns. Although the tone patterns of Itoman were examined in previous studies (Nakasone ms., Hattori 1959, Oshiro 1963, and Hirayama et al. 1966), they ended at the descriptive level, and no phonological accounts for the surface tone patterns were…

  5. Child and Mother Cardiac Vagal Tone: Continuity, Stability, and Concordance across the First 5 Years.

    Science.gov (United States)

    Bornstein, Marc H.; Suess, Patricia E.

    2000-01-01

    Measured vagal tone and heart period at 2 months and 5 years in children and their mothers to evaluate the development of vagal regulation at rest and during an environmental task. Found that children reached adult levels of baseline vagal tone by 5 years and did not differ from mothers in baseline-to-task change in vagal tone or heart period.…

  6. Modelisations des effets de surface sur les jets horizontaux subsoniques d'hydrogene et de methane

    Science.gov (United States)

    Gomez, Luis Fernando

    Le developpement des codes et de normes bases sur une methodologie scientifique requiert la capacite de predire l'etendue inflammable de deversements gazeux d'hydrogene sous differentes conditions. Des etudes anterieures ont deja etabli des modeles bases sur les lois de conservation de la mecanique des fluides basees sur des correlations experimentales qui permettent de predire la decroissance de la concentration et de la vitesse d'un gaz le long de l'axe d'un jet libre vertical. Cette etude s'interesse aux effets de proximite a une surface horizontale parallele sur un jet turbulent. Nous nous interessons a son impact sur l'etendue du champ de la concentration et sur l'enveloppe inflammable en particulier. Cette etude est comparative : l'hydrogene est compare au methane. Ceci permet de degager l'influence des effets de difference de la densite sur le comportement du jet, et de comparer le comportement de l'hydrogene aux correlations experimentales, qui ont ete essentiellement etablies pour le methane. Un modele decrivant l'evolution spatio-temporelle du champ de concentration du gaz dilue est propose, base sur la mecanique des fluides computationnelle. Cette approche permet de varier systematiquement les conditions aux frontieres (proximite du jet a la surface, par exemple) et de connaitre en detail les proprietes de l'ecoulement. Le modele est implemente dans le code de simulations par volumes finis de FLUENT. Les resultats des simulations sont compares avec les lois de similitudes decoulant de la theorie des jets d'ecoulements turbulents libres ainsi qu'avec les resultats experimentaux disponibles. L'effet de la difference des masses molaires des constituantes du jet et des constituantes du milieu de dispersion est egalement etudie dans le contexte du comportement d'echelle de la region developpee du jet.

  7. Carotid Artery Disease

    Science.gov (United States)

    ... brain with blood. If you have carotid artery disease, the arteries become narrow, usually because of atherosclerosis. ... one of the causes of stroke. Carotid artery disease often does not cause symptoms, but there are ...

  8. Peripheral arterial line (image)

    Science.gov (United States)

    A peripheral arterial line is a small, short plastic catheter placed through the skin into an artery of the arm or leg. The purpose of a peripheral arterial line is to allow continuous monitoring of ...

  9. Effet du flambage sur les pipes en composite stratifiés munis d’entailles

    OpenAIRE

    Chenine Halima; Ouinas Djamel; Mohamed Saadi; Djamal Beladam

    2014-01-01

    Dans l’industrie (aéronautiques, automobiles, …) les composites stratifiés se sont imposés pour la fabrication des pièces de structures primaires, grâce à leurs performances, leur qualité, légèreté et souplesse de forme. Cependant l’utilisation de ces matériaux est assujettie à la connaissance de leur comportement mécanique en statique comme en dynamique et également à la possibilité de le simuler. En effet, les matériaux composites ont un comportement particulier, et ceci est du essentiellem...

  10. Effet d’un tourbillon longitudinal sur le comportement d’un profil portant bidimensionnel

    OpenAIRE

    Prothin, Sebastien; Djeridi, Henda; Billard, Jean-Yves

    2010-01-01

    Une situation classique, dans l’agencement du système propulsif d’un navire, consiste à placer le safran de gouvernail à l’aval du propulseur, dans son sillage. Cette situation permet, en particulier, de tirer profit, dans les phases de manoeuvre, de l’effet de « coup de fouet » obtenu en augmentant brutalement la vitesse de rotation (ou le pas) du propulseur pendant une durée très brève. Les interactions qui existent entre le propulseur et le safran de gouvernail ont fait l’objet de diverses...

  11. Modulation of motor excitability by metricality of tone sequences

    DEFF Research Database (Denmark)

    Cameron, David; Stewart, Lauren; Pearce, Marcus;

    2012-01-01

    understood. To investigate how auditory rhythms affect movement, we applied single-pulse transcranial magnetic stimulation (TMS) to primary motor cortex, eliciting motor-evoked potentials (MEPs) in ankle-driving muscles of the lower leg, while participants (N = 4) listened to metrically strong or weak tone......When listening to music, humans tend to synchronize their movements with the perceived beat (e.g., foot-tapping). Brain areas associated with motor function have been closely linked to the perception of beat and rhythm, but the mechanism of this temporal auditory–motor coupling is not fully...... amplitude. These results demonstrate that the pure metrical structure of an auditory rhythm presented as generic parametrically varied tone sequences can influence motor excitability but that the picture may be more complex for real recordings of musical pieces. (PsycINFO Database Record (c) 2013 APA, all...

  12. Categorical Perception of Lexical Tones in Mandarin-speaking Congenital Amusics

    Directory of Open Access Journals (Sweden)

    Wan Ting Huang

    2015-06-01

    Full Text Available Previous research suggests that within Mandarin-speaking congenital amusics, only a subgroup has behavioral lexical tone perception impairments (tone agnosia, whereas the rest of amusics do not. The purpose of the current study was to investigate the categorical nature of lexical tone perception in Mandarin-speaking amusics with and without behavioral lexical tone deficits. Three groups of listeners (controls, pure amusics and amusics with tone agnosia participated in tone identification and discrimination tasks. Indexes of the categorical perception of a physical continuum of fundamental frequencies ranging from a rising to level tone were measured. Specifically, the stimulus durations were manipulated at 100 and 200 ms. For both stimulus durations, all groups exhibited similar categorical boundaries. The pure amusics showed sharp identification slopes and significantly peaked discrimination functions similar to those of normal controls. However, such essential characteristics for the categorical perception of lexical tones were not observed in amusics with tone agnosia. An enlarged step-size from 20 Hz to 35 Hz was not able to produce any discrimination peaks in tone agnosics either. The current study revealed that only amusics with tone agnosia showed a lack of categorical tone perception, while the pure amusics demonstrated typical categorical perception of lexical tones, indicating that the deficit of pitch processing in music does not necessarily result in the deficit in the categorical perception of lexical tones. The different performance between congenital amusics with and without tone agnosia provides a new perspective on the proposition of the relationship between music and speech perception.

  13. Affective tone of mothers' statements to restrict their children's eating.

    Science.gov (United States)

    Pesch, Megan H; Miller, Alison L; Appugliese, Danielle P; Rosenblum, Katherine L; Lumeng, Julie C

    2016-08-01

    Maternal restrictive feeding behaviors have been associated with child weight status. The affective tone of mothers' statements intended to restrict their children's eating has not been examined. The objectives of this study were to describe the affective tone of mothers' restrictive feeding behaviors (positive or negative), and to test the association of child and mother characteristics with rates of Restriction with Positive Affect, Restriction with Negative Affect and Total Restriction. A total of 237 low-income child-mother dyads (mean child age 5.9 years) participated in a videotaped standardized laboratory eating protocol, during which mothers and children were both presented with large servings of cupcakes. A coding scheme was developed to count each restrictive statement with a positive affective tone and each restrictive statement with a negative affective tone. To establish reliability, 20% of videos were double-coded. Demographics and anthropometrics were obtained. Poisson regression models were used to test the association between characteristics of the child and mother with counts of Restriction with Positive Affect, Restriction with Negative Affect, and Total Restriction. Higher rates of Restriction with Positive Affect and Total Restriction were predicted by child obese weight status, and mother non-Hispanic white race/ethnicity. Higher rates of Restriction with Negative Affect were predicted by older child age, child obese weight status, mother non-Hispanic white race/ethnicity, and lower mother education level. In conclusion, in this study mothers of obese (vs. non-obese) children had higher rates of restriction in general, but particularly higher rates of Restriction with Negative Affect. Rather than being told not to restrict, mothers may need guidance on how to sensitively restrict their child's intake. Future studies should consider the contributions of maternal affect to children's responses to maternal restriction. PMID:27090342

  14. Gray tone image watermarking with complementary computer generated holography.

    Science.gov (United States)

    Martinez, Christophe; Laulagnet, Fabien; Lemonnier, Olivier

    2013-07-01

    We present herein an original approach for the watermarking of holograms in gray tone images for use in microscopic halftone image archiving. Our concept is based on the principle of complementary holography presented in a previous contribution. The efficiency of the concept is evaluated theoretically and experimentally. We demonstrate the interest of elliptical diffraction patterns as an alternative to the usual rectangular diffraction patterns and confirm the subsidiary role of the hologram amplitude in the hologram recovery process.

  15. The use of fractal tones in tinnitus patient management

    Directory of Open Access Journals (Sweden)

    Robert W Sweetow

    2013-01-01

    Full Text Available A variety of noises have been employed for decades in an effort to facilitate habituation, mask, or suppress tinnitus. Many of these sounds have reportedly provided benefit, but success has not been universal. More recently, musical stimuli have been added as a sound therapy component. The potential advantages of using such stimuli, in particular fractal tones, in combination with amplification are discussed in this paper.

  16. Reduction of blade passage tone by angle modulation

    Science.gov (United States)

    Fiagbedzi, Y. A.

    1982-05-01

    Blade staggering has been used in both centrifugal and axial flow fans to reduce discrete tones. Impeller hub resilience, causing fan torsional oscillations, appears to be equivalent to blade staggering in that both lead to angle modulation of the blade passage sound. By using Jacobi-Anger expansions, the sound reductions resulting from the angle modulation effects of these two equivalent techniques are predicted. Excellent agreement is found with published data.

  17. Jazz Guitar Improvisation: Beginning with Guide-Tones

    Directory of Open Access Journals (Sweden)

    Daniel Andersen

    2010-12-01

    Full Text Available This article discusses an approach to teaching linear improvisation to beginning jazz guitarists through the function of voice leading in harmonic progressions. The student may gain a clear understanding of improvising melodies by establishing clear visual and aural relationships between the chordal and melodic textures. Three dominant 7th chord voicings are introduced and applied to a twelve bar blues progression in F major. After learning the rhythm guitar accompaniment, single note guide tones consisting of the flat 7th and 3rd chord tones of each dominant seventh chord are extracted from the chord voicings and applied in a melodic texture following chromatic voice leading principles within the harmonic progression. Musicality within the exercises is increased by the addition of a series of rhythmic variations that are applied to the guide-tone lines. Continuing with the concept, full dominant seventh arpeggios are introduced in order to expand the available note choices as a way to build a solid foundation for improvising within harmonic progressions prior to using diatonic scales.

  18. Processing Cantonese lexical tones: Evidence from oddball paradigms.

    Science.gov (United States)

    Jia, S; Tsang, Y-K; Huang, J; Chen, H-C

    2015-10-01

    Two event-related potential (ERP) experiments were conducted to investigate whether Cantonese lexical tones are processed with general auditory perception mechanisms and/or a special speech module. Two tonal features (f0 direction and f0 height deviation) were manipulated to reflect acoustic processing, and the contrast between syllables and hums was used to reveal the involvement of a speech module. Experiment 1 adopted a passive oddball paradigm to study a relatively early stage of tonal processing. Mismatch negativity (MMN) and novelty P3 (P3a) were modulated by the interaction between tonal feature and stimulus type. Similar interactions were found for N2 and P3 in Experiment 2, where more in-depth tonal processing was examined with an active oddball paradigm. Moreover, detecting tonal deviants of syllables elicited N1 and P2 that were not found in hum detection. Together, these findings suggest that the processing of lexical tone relies on both acoustic and linguistic processes from the early stage. Another noteworthy finding is the absence of brain lateralization in both experiments, which challenges the use of a lateralization pattern as evidence for processing lexical tones through a special speech module. PMID:26265553

  19. Arterial Myogenic Activation through Smooth Muscle Filamin A

    Directory of Open Access Journals (Sweden)

    Kevin Retailleau

    2016-03-01

    Full Text Available Mutations in the filamin A (FlnA gene are frequently associated with severe arterial abnormalities, although the physiological role for this cytoskeletal element remains poorly understood in vascular cells. We used a conditional mouse model to selectively delete FlnA in smooth muscle (sm cells at the adult stage, thus avoiding the developmental effects of the knockout. Basal blood pressure was significantly reduced in conscious smFlnA knockout mice. Remarkably, pressure-dependent tone of the resistance caudal artery was lost, whereas reactivity to vasoconstrictors was preserved. Impairment of the myogenic behavior was correlated with a lack of calcium influx in arterial myocytes upon an increase in intraluminal pressure. Notably, the stretch activation of CaV1.2 was blunted in the absence of smFlnA. In conclusion, FlnA is a critical upstream element of the signaling cascade underlying the myogenic tone. These findings allow a better understanding of the molecular basis of arterial autoregulation and associated disease states.

  20. The Time Course for Processing Vowels and Lexical Tones: Reading Aloud Thai Words.

    Science.gov (United States)

    Davis, Chris; Schoknecht, Colin; Kim, Jeesun; Burnham, Denis

    2016-06-01

    Three naming aloud experiments and a lexical decision (LD) experiment used masked priming to index the processing of written Thai vowels and tones. Thai allows for manipulation of the mapping between orthography and phonology not possible in other orthographies, for example, the use of consonants, vowels and tone markers in both horizontal and vertical orthographic positions (HOPs and VOPs). Experiment I showed that changing a vowel between prime and target slowed down target naming but changing a tone mark did not. Experiment I used an across item-design and a different number of HOPs in the way vowels and tones were specified. Experiment 2 used a within-item design and tested vowel and tone changes for both 2-HOP and 3-HOP targets separately. The 3-HOP words showed the same tone and vowel change effect as Experiment 1, whereas 2-HOP items did not. It was speculated that the 2-HOP result was due to the variable position of the vowel affecting priming. Experiment 3 employed a more stringent control over the 2-HOP vowel and tone items and found priming for the tone changes but not for vowel changes. The final experiment retested the items from Experiment 3 with the LD task and found no priming for the tone change items, indicating that the tone effect in Experiment 3 was due to processes involved in naming aloud. In all, the results supported the view that for naming a word, the development of tone information is slower than vowel information. PMID:27363253

  1. Purinergic control of vascular tone in the retina.

    Science.gov (United States)

    Kur, Joanna; Newman, Eric A

    2014-02-01

    Purinergic control of vascular tone in the CNS has been largely unexplored. This study examines the contribution of endogenous extracellular ATP, acting on vascular smooth muscle cells, in controlling vascular tone in the in vivo rat retina. Retinal vessels were labelled by i.v. injection of a fluorescent dye and imaged with scanning laser confocal microscopy. The diameters of primary arterioles were monitored under control conditions and following intravitreal injection of pharmacological agents. Apyrase (500 units ml(-1)), an ATP hydrolysing enzyme, dilated retinal arterioles by 40.4 ± 2.8%, while AOPCP (12.5 mm), an ecto-5'-nucleotidase inhibitor that increases extracellular ATP levels, constricted arterioles by 58.0 ± 3.8% (P < 0.001 for both), demonstrating the importance of ATP in the control of basal vascular tone. Suramin (500 μm), a broad-spectrum P2 receptor antagonist, dilated retinal arterioles by 50.9 ± 3.7% (P < 0.001). IsoPPADS (300 μm) and TNP-ATP (50 μm), more selective P2X antagonists, dilated arterioles by 41.0 ± 5.3% and 55.2 ± 6.1% respectively (P < 0.001 for both). NF023 (50 μm), a potent antagonist of P2X1 receptors, dilated retinal arterioles by 32.1 ± 2.6% (P < 0.001). A438079 (500 μm) and AZ10606120 (50 μm), P2X7 antagonists, had no effect on basal vascular tone (P = 0.99 and P = 1.00 respectively). In the ex vivo retina, the P2X1 receptor agonist α,β-methylene ATP (300 nm) evoked sustained vasoconstrictions of 18.7 ± 3.2% (P < 0.05). In vivo vitreal injection of the gliotoxin fluorocitrate (150 μm) dilated retinal vessels by 52.3 ± 1.1% (P < 0.001) and inhibited the vasodilatory response to NF023 (50 μm, 7.9 ± 2.0%; P < 0.01). These findings suggest that vascular tone in rat retinal arterioles is maintained by tonic release of ATP from the retina. ATP acts on P2X1 receptors, although contributions from other P2X and P2Y receptors cannot be ruled out. Retinal glial cells are a possible source of the vasoconstricting ATP.

  2. A New View of Language Development: The Acquisition of Lexical Tone.

    Science.gov (United States)

    Singh, Leher; Fu, Charlene S L

    2016-05-01

    Research in first language development draws disproportionately from nontone languages. Such research is often presumed to reveal developmental universals in spite of the fact that most languages are tone languages. Recent research in the acquisition of tone languages points to a distinct course of development as compared to nontone languages. Our purpose is to provide an integrated review of research on lexical tone acquisition. First, the linguistic properties and origins of tone languages are described. Following this, research on the acquisition of tones in perception and production is reviewed and integrated. Possible reasons for the uniqueness of tone in language acquisition are discussed. Finally, theoretical advances promised by further research on tone acquisition and specific research directions are proposed.

  3. Effects of Early Bilingual Experience with a Tone and a Non-Tone Language on Speech-Music Integration.

    Science.gov (United States)

    Asaridou, Salomi S; Hagoort, Peter; McQueen, James M

    2015-01-01

    We investigated music and language processing in a group of early bilinguals who spoke a tone language and a non-tone language (Cantonese and Dutch). We assessed online speech-music processing interactions, that is, interactions that occur when speech and music are processed simultaneously in songs, with a speeded classification task. In this task, participants judged sung pseudowords either musically (based on the direction of the musical interval) or phonologically (based on the identity of the sung vowel). We also assessed longer-term effects of linguistic experience on musical ability, that is, the influence of extensive prior experience with language when processing music. These effects were assessed with a task in which participants had to learn to identify musical intervals and with four pitch-perception tasks. Our hypothesis was that due to their experience in two different languages using lexical versus intonational tone, the early Cantonese-Dutch bilinguals would outperform the Dutch control participants. In online processing, the Cantonese-Dutch bilinguals processed speech and music more holistically than controls. This effect seems to be driven by experience with a tone language, in which integration of segmental and pitch information is fundamental. Regarding longer-term effects of linguistic experience, we found no evidence for a bilingual advantage in either the music-interval learning task or the pitch-perception tasks. Together, these results suggest that being a Cantonese-Dutch bilingual does not have any measurable longer-term effects on pitch and music processing, but does have consequences for how speech and music are processed jointly.

  4. Effects of Early Bilingual Experience with a Tone and a Non-Tone Language on Speech-Music Integration.

    Directory of Open Access Journals (Sweden)

    Salomi S Asaridou

    Full Text Available We investigated music and language processing in a group of early bilinguals who spoke a tone language and a non-tone language (Cantonese and Dutch. We assessed online speech-music processing interactions, that is, interactions that occur when speech and music are processed simultaneously in songs, with a speeded classification task. In this task, participants judged sung pseudowords either musically (based on the direction of the musical interval or phonologically (based on the identity of the sung vowel. We also assessed longer-term effects of linguistic experience on musical ability, that is, the influence of extensive prior experience with language when processing music. These effects were assessed with a task in which participants had to learn to identify musical intervals and with four pitch-perception tasks. Our hypothesis was that due to their experience in two different languages using lexical versus intonational tone, the early Cantonese-Dutch bilinguals would outperform the Dutch control participants. In online processing, the Cantonese-Dutch bilinguals processed speech and music more holistically than controls. This effect seems to be driven by experience with a tone language, in which integration of segmental and pitch information is fundamental. Regarding longer-term effects of linguistic experience, we found no evidence for a bilingual advantage in either the music-interval learning task or the pitch-perception tasks. Together, these results suggest that being a Cantonese-Dutch bilingual does not have any measurable longer-term effects on pitch and music processing, but does have consequences for how speech and music are processed jointly.

  5. Effects of Early Bilingual Experience with a Tone and a Non-Tone Language on Speech-Music Integration.

    Science.gov (United States)

    Asaridou, Salomi S; Hagoort, Peter; McQueen, James M

    2015-01-01

    We investigated music and language processing in a group of early bilinguals who spoke a tone language and a non-tone language (Cantonese and Dutch). We assessed online speech-music processing interactions, that is, interactions that occur when speech and music are processed simultaneously in songs, with a speeded classification task. In this task, participants judged sung pseudowords either musically (based on the direction of the musical interval) or phonologically (based on the identity of the sung vowel). We also assessed longer-term effects of linguistic experience on musical ability, that is, the influence of extensive prior experience with language when processing music. These effects were assessed with a task in which participants had to learn to identify musical intervals and with four pitch-perception tasks. Our hypothesis was that due to their experience in two different languages using lexical versus intonational tone, the early Cantonese-Dutch bilinguals would outperform the Dutch control participants. In online processing, the Cantonese-Dutch bilinguals processed speech and music more holistically than controls. This effect seems to be driven by experience with a tone language, in which integration of segmental and pitch information is fundamental. Regarding longer-term effects of linguistic experience, we found no evidence for a bilingual advantage in either the music-interval learning task or the pitch-perception tasks. Together, these results suggest that being a Cantonese-Dutch bilingual does not have any measurable longer-term effects on pitch and music processing, but does have consequences for how speech and music are processed jointly. PMID:26659377

  6. Effects of Early Bilingual Experience with a Tone and a Non-Tone Language on Speech-Music Integration

    Science.gov (United States)

    Asaridou, Salomi S.; Hagoort, Peter; McQueen, James M.

    2015-01-01

    We investigated music and language processing in a group of early bilinguals who spoke a tone language and a non-tone language (Cantonese and Dutch). We assessed online speech-music processing interactions, that is, interactions that occur when speech and music are processed simultaneously in songs, with a speeded classification task. In this task, participants judged sung pseudowords either musically (based on the direction of the musical interval) or phonologically (based on the identity of the sung vowel). We also assessed longer-term effects of linguistic experience on musical ability, that is, the influence of extensive prior experience with language when processing music. These effects were assessed with a task in which participants had to learn to identify musical intervals and with four pitch-perception tasks. Our hypothesis was that due to their experience in two different languages using lexical versus intonational tone, the early Cantonese-Dutch bilinguals would outperform the Dutch control participants. In online processing, the Cantonese-Dutch bilinguals processed speech and music more holistically than controls. This effect seems to be driven by experience with a tone language, in which integration of segmental and pitch information is fundamental. Regarding longer-term effects of linguistic experience, we found no evidence for a bilingual advantage in either the music-interval learning task or the pitch-perception tasks. Together, these results suggest that being a Cantonese-Dutch bilingual does not have any measurable longer-term effects on pitch and music processing, but does have consequences for how speech and music are processed jointly. PMID:26659377

  7. Comparaison des effets des irradiations γ, X et UV dans les fibres optiques

    Science.gov (United States)

    Girard, S.; Ouerdane, Y.; Baggio, J.; Boukenter, A.; Meunier, J.-P.; Leray, J.-L.

    2005-06-01

    Les fibres optiques présentent de nombreux avantages incitant à les intégrer dans des applications devant résister aux environnements radiatifs associés aux domaines civil, spatial ou militaire. Cependant, leur exposition à un rayonnement entraîne la création de défauts ponctuels dans la silice amorphe pure ou dopée qui constitue les différentes parties de la fibre optique. Ces défauts causent, en particulier, une augmentation transitoire de l'atténuation linéique des fibres optiques responsable de la dégradation voire de la perte du signal propagé dans celles-ci. Dans cet article, nous comparons les effets de deux types d'irradiation: une impulsion X et une dose γ cumulée. Les effets de ces irradiations sont ensuite comparés avec ceux induits par une insolation ultraviolette (244 nm) sur les propriétés d'absorption des fibres optiques. Nous montrons qu'il existe des similitudes entre ces différentes excitations et qu'il est possible, sous certaines conditions, d'utiliser celles-ci afin d'évaluer la capacité de certaines fibres optiques à fonctionner dans un environnement nucléaire donné.

  8. The Enduring Significance of Skin Tone: Linking Skin Tone, Attitudes Toward Marriage and Cohabitation, and Sexual Behavior.

    Science.gov (United States)

    Landor, Antoinette M; Halpern, Carolyn Tucker

    2016-05-01

    Past evidence has documented that attitudes toward marriage and cohabitation are related to sexual behavior in adolescence and young adulthood. This study extends prior research by longitudinally testing these associations across racial/ethnic groups and investigating whether culturally relevant variations within racial/ethnic minority groups, such as skin tone (i.e., lightness/darkness of skin color), are linked to attitudes toward marriage and cohabitation and sex. Drawing on family and public health literatures and theories, as well as burgeoning skin tone literature, it was hypothesized that more positive attitudes toward marriage and negative attitudes toward cohabitation would be associated with less risky sex, and that links differed for lighter and darker skin individuals. The sample included 6872 respondents (49.6 % female; 70.0 % White; 15.8 % African American; 3.3 % Asian; 10.9 % Hispanic) from the National Longitudinal Study of Adolescent to Adult Health. The results revealed that marital attitudes had a significantly stronger dampening effect on risky sexual behavior of lighter skin African Americans and Asians compared with their darker skin counterparts. Skin tone also directly predicted number of partners and concurrent partners among African American males and Asian females. We discuss theoretical and practical implications of these findings for adolescence and young adulthood.

  9. The Enduring Significance of Skin Tone: Linking Skin Tone, Attitudes Toward Marriage and Cohabitation, and Sexual Behavior.

    Science.gov (United States)

    Landor, Antoinette M; Halpern, Carolyn Tucker

    2016-05-01

    Past evidence has documented that attitudes toward marriage and cohabitation are related to sexual behavior in adolescence and young adulthood. This study extends prior research by longitudinally testing these associations across racial/ethnic groups and investigating whether culturally relevant variations within racial/ethnic minority groups, such as skin tone (i.e., lightness/darkness of skin color), are linked to attitudes toward marriage and cohabitation and sex. Drawing on family and public health literatures and theories, as well as burgeoning skin tone literature, it was hypothesized that more positive attitudes toward marriage and negative attitudes toward cohabitation would be associated with less risky sex, and that links differed for lighter and darker skin individuals. The sample included 6872 respondents (49.6 % female; 70.0 % White; 15.8 % African American; 3.3 % Asian; 10.9 % Hispanic) from the National Longitudinal Study of Adolescent to Adult Health. The results revealed that marital attitudes had a significantly stronger dampening effect on risky sexual behavior of lighter skin African Americans and Asians compared with their darker skin counterparts. Skin tone also directly predicted number of partners and concurrent partners among African American males and Asian females. We discuss theoretical and practical implications of these findings for adolescence and young adulthood. PMID:26979445

  10. Vasomotor tone does not affect perfusion heterogeneity and gas exchange in normal primate lungs during normoxia

    Science.gov (United States)

    Glenny, R. W.; Robertson, H. T.; Hlastala, M. P.

    2000-01-01

    To determine whether vasoregulation is an important cause of pulmonary perfusion heterogeneity, we measured regional blood flow and gas exchange before and after giving prostacyclin (PGI(2)) to baboons. Four animals were anesthetized with ketamine and mechanically ventilated. Fluorescent microspheres were used to mark regional perfusion before and after PGI(2) infusion. The lungs were subsequently excised, dried inflated, and diced into approximately 2-cm(3) pieces (n = 1,208-1,629 per animal) with the spatial coordinates recorded for each piece. Blood flow to each piece was determined for each condition from the fluorescent signals. Blood flow heterogeneity did not change with PGI(2) infusion. Two other measures of spatial blood flow distribution, the fractal dimension and the spatial correlation, did not change with PGI(2) infusion. Alveolar-arterial O(2) differences did not change with PGI(2) infusion. We conclude that, in normal primate lungs during normoxia, vasomotor tone is not a significant cause of perfusion heterogeneity. Despite the heterogeneous distribution of blood flow, active regulation of regional perfusion is not required for efficient gas exchange.

  11. P2 receptors in the central and peripheral nervous systems modulating sympathetic vasomotor tone.

    Science.gov (United States)

    Ralevic, V

    2000-07-01

    Arterial pressure depends on the level of activity of sympathetic vasoconstrictor outflow to blood vessels. This activity is generated in the central nervous system, and involves inputs from a variety of brain regions projecting to sympathetic preganglionic neurones. Of especial interest are a group of neurones in the rostral ventrolateral medulla (RVLM), as they have been demonstrated to have a fundamental role in reflex regulation of the cardiovascular system, and in generation of tonic drive to sympathetic outflow. Sympathetic outflow to blood vessels is additionally modulated at sympathetic ganglia, and at the peripheral terminals of sympathetic nerves. This review considers the role of P2 purine receptors in this neural pathway. Ionotropic P2X receptors are expressed in the RVLM, in sympathetic ganglia, and at the sympathetic neuromuscular junction, and mediate fast excitatory neurotransmission, indicating a general role for ATP as a regulator of sympathetic vasomotor tone. P2Y receptors couple to G proteins and mediate slower signalling to ATP; they have been reported to inhibit prejunctionally neurotransmission at the peripheral terminals of sympathetic nerves, but little is known about their possible role in the central nervous system and in sympathetic ganglia.

  12. Focal ischaemia caused by instability of cerebrovascular tone during attacks of hemiplegic migraine. A regional cerebral blood flow study

    DEFF Research Database (Denmark)

    Friberg, L; Olsen, T S; Roland, P E;

    1987-01-01

    During the course of hemiplegic migraine in 3 patients, changes in regional cerebral blood flow (rCBF) were recorded by the intracarotid 133Xe method and a 254 multidetector camera covering one hemisphere. The rCBF measurements were performed in conjunction with cerebral angiography. During...... repeated rCBF measurements all 3 patients developed focal hypoperfusion originating in the frontal lobe, subsequently spreading posteriorly to involve the precentral and postcentral regions. In 2 cases focal hyperperfusion appeared to precede the hypoperfusion. In association with the rCBF changes...... the patients developed transient motor and/or sensory deficits and subsequently severe headache. No signs of arterial occlusion were found. In the over and underperfused regions blood flow fluctuated rapidly because of instability of cerebrovascular tone, defined as transient constriction of the smallest...

  13. Contractile responses to ergotamine and dihydroergotamine in the perfused middle cerebral artery of rat

    OpenAIRE

    Tfelt-Hansen, Peer; Nilsson, Elisabeth; Edvinsson, Lars

    2007-01-01

    The vasomotor effects of ergotamine and dihydroergotamine (DHE) on the middle cerebral artery (MCA) of rats were studied using the pressurised arteriography method and in vitro myographs. MCAs from Sprague–Dawley rats were mounted on two glass micropipettes using the arteriograph, pressurised to 85 mmHg and luminally perfused. All vessels used attained spontaneous contractile tone (34.9±1.8% of resting tone) and responded to luminal adenosine triphosphate (ATP) with dilatation (24.1±4.0%), wh...

  14. Cantonese tone production performance of mainstream school children with hearing impairment.

    Science.gov (United States)

    Cheung, Karen K L; Lau, Ada H Y; Lam, Joffee H S; Lee, Kathy Y S

    2014-12-01

    This study investigated the Cantonese tone production ability of children with hearing impairment studying in mainstream schools. The participants were 87 Cantonese-speaking children with mild-to-profound degrees of hearing loss aged 5.92-13.58 in Hong Kong. Most of the children were fitted with hearing aids (n = 65); 17 of them had profound hearing impairment, one who had severe hearing loss had cochlear implantation, and four who had mild hearing loss were without any hearing device. The Hong Kong Cantonese Articulation Test was administered, and the tones produced were rated by two of the authors and a speech-language pathologist. Group effects of tones, hearing loss level, and also an interaction of the two were found to be significant. The children with profound hearing impairment performed significantly worse than most of the other children. Tone 1 was produced most accurately, whereas tone 6 productions were the poorest. No relationship was found between the number of years of mainstreaming and tone production ability. Tone production error pattern revealed that confusion patterns in tone perception coincided with those in production. Tones having a similar fundamental frequency (F0) at the onset also posed difficulty in tone production for children with hearing impairment.

  15. Arm Robot Surveillance Using Dual Tone Multiple Frequency Technology

    Directory of Open Access Journals (Sweden)

    Amrutha.V

    2014-09-01

    Full Text Available Surveillance place a pivotal role in addressing a wide range of security challenges .In the present paper we propose a Dual Tone Multiple Frequency ( DTMF based Robot with video surveillance. In the proposed model a DTMF based Robot with video surveillance with multiple key functions, Arm picker and security system was implemented. Master and slave concept using 3 Microcontroller and motor driver IC to drive motors was implemented and belt wheel platform was used to move the robot from one place to another. Multiple key functions were used to perform more functions and a camera for surveillance .The robot can navigate with the help of the user.

  16. L-band tone-code-data transponder calibration

    Science.gov (United States)

    Brisken, A. F.

    1977-01-01

    The objectives of this program were to identify and quantify factors which affect the performance of the L-band tone-code-data ranging transponders. Specific objectives included the following: (1) assemble the L-band ranging transponder, previously deployed in Hawaii for the tracking of the ATS-5 satellite, at the GE Radio-Optical Observatory; (2) configure the observatory to conduct calibration exercises with the transponder; and (3) conduct sufficient calibration experiments to demonstrate factors which degrade transponder accuracy, precision, and reliability, to quantify these factors where possible, and to verify long term transponder stability under controlled conditions.

  17. Pharmacological and molecular comparison of K(ATP) channels in rat basilar and middle cerebral arteries

    DEFF Research Database (Denmark)

    Ploug, Kenneth Beri; Edvinsson, Lars; Olesen, Jes;

    2006-01-01

    basilar and middle cerebral arteries using quantitative real-time PCR (Polymerase Chain Reaction) and Western blotting, respectively. In the perfusion system, we found no significant responses after luminal application of three K(ATP) channel openers to rat basilar and middle cerebral arteries......ATP-sensitive potassium (K(ATP)) channels play an important role in the regulation of cerebral vascular tone. In vitro studies using synthetic K(ATP) channel openers suggest that the pharmacological profiles differ between rat basilar arteries and rat middle cerebral arteries. To address this issue......, we studied the possible involvement of endothelial K(ATP) channels by pressurized arteriography after luminal administration of synthetic K(ATP) channel openers to rat basilar and middle cerebral arteries. Furthermore, we examined the mRNA and protein expression profile of K(ATP) channels to rat...

  18. Pharmacological and molecular comparison of K(ATP) channels in rat basilar and middle cerebral arteries

    DEFF Research Database (Denmark)

    Ploug, Kenneth Beri; Edvinsson, Lars; Olesen, Jes;

    2006-01-01

    ATP-sensitive potassium (K(ATP)) channels play an important role in the regulation of cerebral vascular tone. In vitro studies using synthetic K(ATP) channel openers suggest that the pharmacological profiles differ between rat basilar arteries and rat middle cerebral arteries. To address this issue......, we studied the possible involvement of endothelial K(ATP) channels by pressurized arteriography after luminal administration of synthetic K(ATP) channel openers to rat basilar and middle cerebral arteries. Furthermore, we examined the mRNA and protein expression profile of K(ATP) channels to rat...... basilar and middle cerebral arteries using quantitative real-time PCR (Polymerase Chain Reaction) and Western blotting, respectively. In the perfusion system, we found no significant responses after luminal application of three K(ATP) channel openers to rat basilar and middle cerebral arteries. In...

  19. [Abnormal popliteal arteries].

    Science.gov (United States)

    Elbaz, C

    1975-01-01

    Arteriopathy restricted to the popliteal artery, except in cases of atheroma, must indicate three of four unusual diagnoses: the trapped popliteal artery and the dessicating haematoma are anatomo-clinical entities that have been identified only relatively recently. The popliteal artery may be trapped by the medial gastrocnomius muscle, round the tendon of which the artery passes (totally or partially). This results in compression of the artery and eventually in thrombosis. Clinically, intermittent claudication is seen that may deteriorate and lead to gangrene of the toes. Arteriography makes it possible to diagnose the condition as the condition as the artery is considerably displaced inwards. Surgical correction is simple: sectioning of the tendon and repositioning of the artery. Dessicating haematoma of the popliteal artery is due essentially to atheroma, associated with medianecrosis. A "egg-timer" stenosis is found by arteriography and this condition also progresses towards thrombosis. Arterial restoration is called for, usually by bridging. PMID:1230799

  20. covert contrast: The acquisition of Mandarin tone 2 and tone 3 in L2 production and perception

    Science.gov (United States)

    Mar, Li-Ya

    This dissertation investigates the occurrence of an intermediate stage, termed a covert contrast, in the acquisition of Mandarin Tone 2 (T2) and Tone 3 (T3) by adult speakers of American English. A covert contrast is a statistically reliable distinction produced by language learners that is not perceived by native speakers of the target language (TL). In second language (L2) acquisition, whether a learner is judged as having acquired a TL phonemic contrast has largely depended on whether the contrast was perceived and transcribed by native speakers of the TL. However, categorical perception has shown that native listeners cannot perceive a distinction between two sounds that fall within the same perceptual boundaries on the continuum of the relevant acoustic cues. In other words, it is possible that native speakers of the TL do not perceive a phonemic distinction that is produced by L2 learners when that distinction occurs within a phonemic boundary of TL. The data for the study were gathered through two elicitations of tone production, a longitudinal analysis, and two perception tasks. There were three key findings. First, both elicitations showed that most of the L2 participants produced a covert contrast between T2 and T3 on at least one of the three acoustic measures used in the study. Second, the longitudinal analysis reveals that some L2 participants progressed from making a covert contrast to a later stage of implementing an overt one, thereby supporting the claim that making a covert contrast is an intermediate stage in the process of acquiring a L2 phonemic contrast. Third, results of the perceptual tasks showed no reliable difference in identifying and discriminating Mandarin T2 and T3 on the part of the L2 learners who produced a covert contrast and those who produced an overt contrast, indicating that there was no reliable difference in the two groups' ability to perceive the target tones. In all, the occurrence of a covert contrast in the process of

  1. Effets oculaires de la tranquilisation avec le buthorphanol chez le chien

    OpenAIRE

    Dongay, Agnès

    2014-01-01

    Le butorphanol est utilisé en médecine vétérinaire pour ses propriétés analgésiques et sédatives dans divers protocoles anesthésiques L’objectif de cette étude était d’évaluer les effets oculaires de la sédation au butorphanol lors d’un examen ophtalmologique de routine. Vingt-deux beagles sans anomalie oculaire ont reçu une injection intramusculaire de butorphanol à la dose de 0,2 mg/kg. Des examens cliniques répétés ont été effectués 20 minutes avant et juste avant l’administration puis 10,...

  2. L'effet Casimir : théorie et expériences

    Science.gov (United States)

    Lambrecht, A.; Genet, C.; Intravaia, F.; Reynaud, S.

    2004-11-01

    L'existence de fluctuations irréductibles de champ dans le vide est une prédiction importante de la théorie quantique. Ces fluctuations ont de nombreuses conséquences observables comme l'effet Casimir, qui est maintenant mesuré avec une bonne précision et un bon accord avec la théorie, pourvu que celle-ci tienne compte des différences entre les expériences rélles et la situation idéale considérée par H.G.B. Casimir. Nous présenterons quelqu'unes des expériences récentes et discuterons les principales corrections à la force de Casimir liées à la situation expérimentale.

  3. Bruit thermique et effets quantiques dans une cavité optique de grande finesse

    Science.gov (United States)

    Caniard, T.; Briant, T.; Heidmann, A.; Pinard, M.

    2006-10-01

    Nous nous intéressons aux bruits dans les mesures optiques de très grande sensibilité et aux limites associées. Une des limitations fondamentales des mesures interférométriques, telles que les détections d'ondes gravitationnelles, est liée aux fluctuations de la pression de radiation exercée par la lumière sur les miroirs. Celle-ci induit des corrélations quantiques entre la position des miroirs et les fluctuations de la lumière. L'observation de ces effets quantiques ouvrirait de nombreuses perspectives: étude de la limite quantique standard, production d'états comprimés, réalisation d'une mesure quantique non destructive ldots

  4. Effets associes a la mutation "coquille blanche" chez la caille japonaise

    OpenAIRE

    Monvoisin, Jean Louis; Merat, P; Coquerelle, Gerard; Costa da Silva, Jose

    1989-01-01

    Nous avons recherché les effets directs ou maternels sur diverses performances associés à un gène autosomal récessif (we), responsable de l’absence de pigmentation des coquilles d’oeufs chez la caille japonaise. A partir d’animaux des deux sexes de même origine, respectivement de génotype hétérozygote We+ we et homozygote récessif wewe, les croisements réciproques ♂ we we x ♀ We+ we et ♂ We+ we X ♀ we we ont été réalisés deux années consécutives. Ces croisements donnaient tous deux des...

  5. Effets de la pratique des jeux vidéo sur le vieillissement cognitif

    OpenAIRE

    Maillot, Pauline; Perrot, Alexandra; Hartley, Alan

    2012-01-01

    L'avancée en âge s'accompagne de nombreux déclins cognitifs, mais reste cependant un phénomène très hétérogène. En effet, plusieurs facteurs extrinsèques semblent moduler l'impact du vieillissement sur la cognition. Récemment, une série d'études a mis en évidence que la pratique des jeux vidéo pouvait engendrer de nombreux bénéfices en faveur du maintien de la vitalité cognitive des seniors. Cette revue de littérature vise donc à établir un état des lieux précis de la relation entre les diffé...

  6. Computing Axisymmetric Jet Screech Tones using Unstructured Grids

    Science.gov (United States)

    Jorgenson, Philip C. E.; Loh, Ching Y.

    2003-01-01

    The purpose of this paper is to show that computations with an aeroacoustic feedback loop, the jet screech noise, can be obtained using truly unstructured grid technology. Numerical results are presented for a nozzle with two different lip thicknesses which will be referred to in this paper as a thin and a thick lip nozzle respectively. The space-time conservation element and solution element (CE/SE) method is used to solve the conservation laws of the compressible axisymmetric Navier-Stokes equations. The equations are time marched to predict the unsteady flow and the near-field screech tone noise issuing from an underexpanded circular jet. The CE/SE method uses an unstructured grid based data structure. The unstructured grids for these calculations are generated based on the method of Delaunay triangulation. Comparisons of numerical results with available experimental data are shown for flows corresponding to several different jet Mach numbers. Generally good agreement is obtained in terms of flow physics, screech tone frequency, and sound pressure level.

  7. Predicting the decay time of solid body electric guitar tones.

    Science.gov (United States)

    Paté, Arthur; Le Carrou, Jean-Loïc; Fabre, Benoît

    2014-05-01

    Although it can be transformed by various electronic devices, the sound of the solid body electric guitar originates from, and is strongly linked with, the string vibration. The coupling of the string with the guitar alters its vibration and can lead to decay time inhomogeneities. This paper implements and justifies a framework for the study of decay times of electric guitar tones. Two damping mechanisms are theoretically and experimentally identified: the string intrinsic damping and the damping due to mechanical coupling with the neck of the guitar. The electromagnetic pickup is shown to not provide any additional damping to the string. The pickup is also shown to be far more sensitive to the out-of-plane polarization of the string. Finally, an accurate prediction of the decay time of electric guitar tones is made possible, whose only requirements are the knowledge of the isolated string dampings and the out-of-plane conductance at the neck of the guitar. This prediction can be of great help for instrument makers and manufacturers. PMID:24815284

  8. Contrastive analysis on tone between Putonghua and Taiwan Mandarin

    Institute of Scientific and Technical Information of China (English)

    DENG Dan; SHI Feng; L(U) Shinan

    2008-01-01

    The differences of the pitch and duration of Chinese syllables between Putonghua(PTH) and Taiwan Mandarin (TM) were studied. The speech materials to be used are not only isolated syllables, but also sentences. The results reveal that: For the isolated syllables, T1 and T2 in TM are influenced by Minnan dialect, therefore their pitch are lower than those in PTH. T3 is fall-rise in PTH, while it is fall in TM. Moreover, the syllable duration sequence for different tone is T3>T2>T1>T4 in PTH, while it is T1>T2>T3>T4 in TM. For the syllables in sentences, T2 is mid-rise in PTH, while it is mid-level in TM. And the T3 is longer than T4 but shorter than T1 or T2 in PTH, while it is the shortest in TM. Furthermore the effects of prosodic phrase boundary on duration for different tones are almost the same in PTH, but the lengthening part of T1 or T2 is longer than that of T3 or T4 in TM.

  9. Vagal tone: effects on sensitivity, motility, and inflammation.

    Science.gov (United States)

    Bonaz, B; Sinniger, V; Pellissier, S

    2016-04-01

    The vagus nerve (VN) is a key element of the autonomic nervous system. As a mixed nerve, the VN contributes to the bidirectional interactions between the brain and the gut, i.e., the brain-gut axis. In particular, after integration in the central autonomic network of peripheral sensations such as inflammation and pain via vagal and spinal afferents, an efferent response through modulation of preganglionic parasympathetic neurons of the dorsal motor nucleus of the vagus and/or preganglionic sympathetic neurons of the spinal cord is able to modulate gastrointestinal nociception, motility, and inflammation. A low vagal tone, as assessed by heart rate variability, a marker of the sympatho-vagal balance, is observed in functional digestive disorders and inflammatory bowel diseases. To restore a normal vagal tone appears as a goal in such diseases. Among the therapeutic tools, such as drugs targeting the cholinergic system and/or complementary medicine (hypnosis, meditation…), deep breathing, physical exercise, VN stimulation (VNS), either invasive or non-invasive, appears as innovative. There is new evidence in the current issue of this Journal supporting the role of VNS in the modulation of gastrointestinal functions. PMID:27010234

  10. Arterial dysfunction but maintained systemic blood pressure in cavin-1-deficient mice.

    Directory of Open Access Journals (Sweden)

    Karl Swärd

    Full Text Available Caveolae are omega-shaped plasma membrane micro-domains that are abundant in cells of the vascular system. Formation of caveolae depends on caveolin-1 and cavin-1 and lack of either protein leads to loss of caveolae. Mice with caveolin-1 deficiency have dysfunctional blood vessels, but whether absence of cavin-1 similarly leads to vascular dysfunction is not known. Here we addressed this hypothesis using small mesenteric arteries from cavin-1-deficient mice. Cavin-1-reporter staining was intense in mesenteric arteries, brain arterioles and elsewhere in the vascular system, with positive staining of both endothelial and smooth muscle cells. Arterial expression of cavin-1, -2 and -3 was reduced in knockout (KO arteries as was expression of caveolin-1, -2 and -3. Caveolae were absent in the endothelial and smooth muscle layers of small mesenteric arteries as determined by electron microscopy. Arginase, a negative regulator of nitric oxide production, was elevated in cavin-1 deficient arteries as was contraction in response to the α1-adrenergic agonist cirazoline. Detailed assessment of vascular dimensions revealed increased media thickness and reduced distensibility, arguing that enhanced contraction was due to increased muscle mass. Contrasting with increased α1-adrenergic contraction, myogenic tone was essentially absent and this appeared to be due in part to increased nitric oxide production. Vasomotion was less frequent in the knock-out vessels. In keeping with the opposing influences on arterial resistance of increased agonist-induced contractility and reduced myogenic tone, arterial blood pressure was unchanged in vivo. We conclude that deficiency of cavin-1 affects the function of small arteries, but that opposing influences on arterial resistance balance each other such that systemic blood pressure in unstressed mice is well maintained.

  11. Exploring the Impact of Skin Tone on Family Dynamics and Race-Related Outcomes

    OpenAIRE

    Landor, Antoinette M.; Simons, Leslie Gordon; Simons, Ronald L.; Gene H. Brody; Bryant, Chalandra M.; Gibbons, Frederick X.; Granberg, Ellen M.; Melby, Janet N.

    2013-01-01

    Racism has historically been a primary source of discrimination against African Americans but there has been little research on the role that skin tone plays in explaining experiences with racism. Similarly, colorism within African American families and the ways in which skin tone influences family processes is an understudied area of research. Utilizing data from a longitudinal sample of African American families (N= 767), we assessed whether skin tone impacted experiences with discriminatio...

  12. Phonological abstraction in processing lexical-tone variation: Evidence from a learning paradigm

    OpenAIRE

    Mitterer, H.; Y. Chen; Zhou, X.(Wuhan University, Wuhan 430072, China)

    2011-01-01

    There is a growing consensus that the mental lexicon contains both abstract and word-specific acoustic information. To investigate their relative importance for word recognition, we tested to what extent perceptual learning is word specific or generalizable to other words. In an exposure phase, participants were divided into two groups; each group was semantically biased to interpret an ambiguous Mandarin tone contour as either tone1 or tone2. In a subsequent test phase, the perception of amb...

  13. Dopamine receptors in the substantia nigra are involved in the regulation of muscle tone.

    OpenAIRE

    Double, K L; Crocker, A D

    1995-01-01

    The aim of the present study was to localize the dopamine receptors involved in the regulation of muscle tone. A strategy was used whereby the effects on muscle tone of injecting the irreversible dopamine receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) in discrete brain regions were assessed. Increases in muscle tone were measured as changes in electromyographic activity of the gastrocnemius and tibialis muscles of conscious, unrestrained rats. No increases in muscle...

  14. Effets économiques de l’aide publique au développement en suisse

    Directory of Open Access Journals (Sweden)

    Gilles Carbonnier

    2012-11-01

    Full Text Available Cette étude porte sur les effets des dépenses d’aide publique au développement (APD sur l’économie suisse. Elle examine les apports générés par les dépenses d’APD sur le produit intérieur brut (PIB et sur l’emploi en Suisse pour l’année 2010. Il s’agit de la cinquième étude du genre, après celles de 1994, 1998, 2002 et 2006. Ce rapport présente les résultats de manière détaillée. Un résumé synthétique a été publié séparément sur les sites Internet de la DDC1 et du SECO2 en février 2012.L’approche méthodologique consiste à évaluer les retombées économiques induites par les achats de biens et services ainsi que par les salaires versés au titre de l’APD. Dans une première étape, l’étude calcule l’incidence de l’APD sur la demande globale3 en Suisse. Ensuite, elle évalue l’effet multiplicateur de cette hausse initiale de la demande sur le produit intérieur brut (PIB suisse, ce qui permet finalement d’estimer l’impact en termes d’emplois, en fonction de la productivité moyenne du travail en Suisse. Les résultats de cette étude démontrent à nouveau que les dépenses d’APD génèrent des effets clairement positifs pour l’économie suisse. Pour l’année 2010 :- en conservant les mêmes hypothèses de calcul que pour les études précédentes, le volume total de l’APD, de 2,4 milliards de CHF suisses, a généré un apport de revenus de 3,6 milliards de CHF. Autrement dit, chaque CHF d’aide a généré, en moyenne, des retombées de 1,55 CHF sur le PIB suisse. Sur la base de la productivité moyenne du travail en Suisse, les retombées sur le marché du travail sont estimées à 25 000 emplois à plein temps ;- en révisant certaines hypothèses de calcul pour refléter l’évolution de la composition de l’APD et afin d’éviter tout risque de surévaluer les résultats, les retombées par CHF d’APD sur le PIB se montent à 1,29 CHF en moyenne, et l

  15. Effects of musical and linguistic experience on categorization of lexical and melodic tones.

    Science.gov (United States)

    Chang, Daniel; Hedberg, Nancy; Wang, Yue

    2016-05-01

    This study investigated the categorization of Mandarin lexical tones and music melodic tones by listeners differing in linguistic and musical experience (English musicians, English non-musicians, and Mandarin non-musicians). Linguistic tonal continua were created from the Mandarin rising to level, and falling to level tones. Melodic continua were created by varying the note D under the context of C and E. The tasks involved tone discrimination and identification. Results revealed that musical training facilitated Mandarin tone categorization, with English musicians' tone identification approximating native Mandarin patterns, being more categorical than English non-musicians'. However, English musicians showed higher discrimination accuracy than Mandarin listeners but not English non-musicians. This suggests that musical experience was not advantageous in discriminating linguistic tonal variations, which requires listeners to ignore subtle physical differences in order to make categorical judgments. Similarly, Mandarin tone experience affected melodic tone identification, with Mandarin non-musicians approximating English musicians, showing more categorical patterns than English non-musicians. In contrast, Mandarin non-musicians' melodic discrimination was the poorest among the three groups, indicating that their experience with linguistic tone categorization may have decreased their sensitivity to fine-grained pitch variations. These results demonstrate bi-directional transfer of pitch proficiency between speech and music as a function of experience. PMID:27250140

  16. Preattentive processing of emotional musical tones: a multidimensional scaling and ERP study

    Directory of Open Access Journals (Sweden)

    Thomas F Münte

    2013-09-01

    Full Text Available Musical emotion can be conveyed by subtle variations in timbre. Here, we investigated whether the brain is capable to discriminate tones differing in emotional expression by recording event-related potentials (ERPs in an oddball paradigm under preattentive listening conditions. First, using multidimensional Fechnerian scaling, pairs of violin tones played with a happy or sad intonation were rated same or different by a group of non-musicians. Three happy and three sad tones were selected for the ERP experiment. The Fechnerian distances between tones within an emotion were in the same range as the distances between tones of different emotions. In two conditions, either 3 happy and 1 sad or 3 sad and 1 happy tone were presented in pseudo-random order. A mismatch negativity for the emotional deviant was observed, indicating that in spite of considerable perceptual differences between the three equiprobable tones of the standard emotion, a template was formed based on timbral cues against which the emotional deviant was compared. Based on Juslin’s assumption of redundant code usage, we propose that tones were grouped together, because they were identified as belonging to one emotional category based on different emotion-specific cues. These results indicate that the brain forms an emotional memory trace at a preattentive level and thus extends previous investigations in which emotional deviance was confounded with physical dissimilarity. Differences between sad and happy tones were observed which might be due to the fact that the happy emotion is mostly communicated by suprasegmental features.

  17. Preattentive processing of emotional musical tones: a multidimensional scaling and ERP study

    Science.gov (United States)

    Spreckelmeyer, Katja N.; Altenmüller, Eckart; Colonius, Hans; Münte, Thomas F.

    2013-01-01

    Musical emotion can be conveyed by subtle variations in timbre. Here, we investigated whether the brain is capable to discriminate tones differing in emotional expression by recording event-related potentials (ERPs) in an oddball paradigm under preattentive listening conditions. First, using multidimensional Fechnerian scaling, pairs of violin tones played with a happy or sad intonation were rated same or different by a group of non-musicians. Three happy and three sad tones were selected for the ERP experiment. The Fechnerian distances between tones within an emotion were in the same range as the distances between tones of different emotions. In two conditions, either 3 happy and 1 sad or 3 sad and 1 happy tone were presented in pseudo-random order. A mismatch negativity for the emotional deviant was observed, indicating that in spite of considerable perceptual differences between the three equiprobable tones of the standard emotion, a template was formed based on timbral cues against which the emotional deviant was compared. Based on Juslin's assumption of redundant code usage, we propose that tones were grouped together, because they were identified as belonging to one emotional category based on different emotion-specific cues. These results indicate that the brain forms an emotional memory trace at a preattentive level and thus, extends previous investigations in which emotional deviance was confounded with physical dissimilarity. Differences between sad and happy tones were observed which might be due to the fact that the happy emotion is mostly communicated by suprasegmental features. PMID:24065950

  18. Improvement of Tone Intelligibility for Average-Voice-Based Thai Speech Synthesis

    Directory of Open Access Journals (Sweden)

    Suphattharachai Chomphan

    2012-01-01

    Full Text Available Problem statement: Tone intelligibility in speech synthesis is an important attribute that should be taken into account. The tone correctness of the synthetic speech is degraded considerably in the average-voice-based HMM-based Thai speech synthesis. The tying mechanism in the decision tree based context clustering without appropriate criterion causes unexpected tone neutralization. Incorporation of the phrase intonation to the context clustering process in the training stage was proposed early. However, the tone correctness is not satisfied. Approach: This study proposes a number of tonal features including tone-geometrical features and phrase intonation features to be exploited in the context clustering process of HMM training stage. Results: In the experiments, subjective evaluations of both average voice and adapted voice in terms of the intelligibility of tone are conducted. Effects on decision trees of the extracted features are also evaluated. By considering gender in training speech, two core experiments were conducted. The first experiment shows that the proposed tonal features can improve the tone intelligibility for female speech model above that of male speech model, while the second experiment shows that the proposed tonal features improve the tone intelligibility for gender dependent model than for gender independent model. Conclusion: All of the experimental results confirm that the tone correctness of the synthesized speech from the average-voice-based HMM-based Thai speech synthesis is significantly improved when using most of the extracted features.

  19. Acquisition of Mandarin Lexical Tones:The Effect of Global Pitch T endency

    Institute of Scientific and Technical Information of China (English)

    CHUNSHENG YANG

    2014-01-01

    This paper discusses the acquisition of Mandarin lexical tones by American second language ( L2 ) learners . The analysis of the tone errors in the reading passage and the spontaneous speech showed that the surface Tone 4 error is the most frequent at the prosodic word ( PW )‐initial position in both the intermediate and the advanced learner groups . Attempts were made to account for this tone error pattern within some second language acquisition (SLA) frameworks , but in vain . It was argued that this tone error pattern may be due to the high pitch tendency at the phrase‐or sentence‐initial position in speech . Although this is more of a general pattern across languages , the production of such a tendency by L2 learners superseded the underlying tones , hence the surface Tone 4 errors . The special status of Tone 4 in L2 speech corresponds to the special status of the same tone in the first language (L1 ) speech (Wan , 2007 ) . However , it was cautioned that such similarity should not be taken as evidence for the similarity in L1 and L2 acquisition in that different processes are involved in L1 and L2 production .

  20. Combination of Rare Right Arterial Variation with Anomalous Origins of the Vertebral Artery, Aberrant Subclavian Artery and Persistent Trigeminal Artery

    Science.gov (United States)

    Ishihara, H.; San Millán Ruíz, D.; Abdo, G.; Asakura, F.; Yilmaz, H.; Lovblad, K.O.; Rüfenacht, D.A.

    2011-01-01

    Summary A 32-year-old woman hospitalized for subarachnoid hemorrhage showed rare arterial variation on the right side with anomalous origins of the vertebral artery, aberrant subclavian artery and persistent trigeminal artery. Angiography showed the right vertebral artery to originate from the right common carotid artery, the right subclavian artery to arise separately from the descending aorta, and persistent trigeminal artery on the right side. The possible embryonic mechanism of this previously unreported variant combination is discussed. PMID:22005696

  1. On Renal Artery Stenosis

    OpenAIRE

    Eklöf, Hampus

    2005-01-01

    Renal artery stenosis (RAS) is a potentially curable cause of hypertension and azotemia. Besides intra-arterial renal angiography there are several non-invasive techniques utilized to diagnose patients with suspicion of renal artery stenosis. Removing the stenosis by revascularization to restore unobstructed blood flow to the kidney is known to improve and even cure hypertension/azotemia, but is associated with a significant complication rate. To visualize renal arteries with x-ray technique...

  2. Melodic Pitch Perception and Lexical Tone Perception in Mandarin-Speaking Cochlear Implant Users

    Science.gov (United States)

    Tao, Duoduo; Deng, Rui; Jiang, Ye; Galvin, John J.; Fu, Qian-Jie; Chen, Bing

    2014-01-01

    Objectives To examine the relationship between lexical tone perception and melodic pitch perception in Mandarin-speaking cochlear implant (CI) users, and to investigate the influence of previous acoustic hearing on CI users’ speech and music perception. Design Lexical tone perception and melodic contour identification (MCI) were measured in 21 prelingual and 11 postlingual young (age: 6–26 years old) Mandarin-speaking CI users. Lexical tone recognition was measured for four tonal patterns: Tone 1 (flat F0), Tone 2 (rising F0), Tone 3 (falling-rising F0), and Tone 4 (falling F0). MCI was measured using 9 five-note melodic patterns that contained changes in pitch contour, as well as different semitone spacing between notes. Results Lexical tone recognition was generally good (overall mean = 81% correct), and there was no significant difference between subject groups. MCI performance was generally poor (mean = 23% correct). MCI performance was significantly better for postlingual (mean = 32% correct) than for prelingual CI participants (18% correct). After correcting for outliers, there was no significant correlation between lexical tone recognition and MCI performance for prelingual or post-lingual CI participants. Age at deafness was significantly correlated with MCI performance only for postlingual participants. CI experience was significantly correlated with MCI performance for both prelingual and postlingual participants. Duration of deafness was significantly correlated with tone recognition only for prelingual participants. Conclusions Despite the prevalence of pitch cues in Mandarin, the present CI participants had great difficulty perceiving melodic pitch. The availability of amplitude and duration cues in lexical tones most likely compensated for the poor pitch perception observed with these CI listeners. Previous acoustic hearing experience seemed to benefit postlingual CI users’ melodic pitch perception. Longer CI experience was associated with

  3. Cortical Auditory Event Related Potentials (P300) for Frequency Changing Dynamic Tones

    Science.gov (United States)

    Kalaiah, Mohan Kumar

    2016-01-01

    Background and Objectives P300 has been studied with a variety of stimuli. However, the nature of P300 has not been investigated for deviant stimuli which change its characteristics from standard stimuli after a period of time from onset. Subjects and Methods Nine young adults with normal hearing participated in the study. The P300 was elicited using an oddball paradigm, the probability of standard and deviant stimuli was 80% and 20% respectively. Six stimuli were used to elicit P300, it included two pure-tones (1,000 Hz and 2,000 Hz) and four tone-complexes (tones with frequency changes). Among these stimuli, 1,000 Hz tone served as standard while others served as deviant stimuli. The P300 was recorded in five separate blocks, with one of the deviant stimuli as target in each block. Electroencephalographic was recorded from electrode sites Fz, Cz, C3, C4, and Pz. Latency and amplitude of components of the cortical auditory evoked potentials were measured at Cz. Results Waveforms obtained in the present study shows that, all the deviant stimuli elicited obligatory P1-N1-P2 for stimulus onset. 2,000 Hz deviant tone elicited P300 at a latency of 300 ms. While, tone-complexes elicited acoustic change complex (ACC) for frequency changes and finally elicited P300 at a latency of 600 ms. In addition, the results showed shorter latency and larger amplitude ACC and P300 for rising tone-complexes compared to falling tone-complexes. Conclusions Tone-complexes elicited distinct waveforms compared to 2,000 Hz deviant tone. Rising tone-complexes which had an increase in frequency elicited shorter latency and larger amplitude responses, which could be attributed to perceptual bias for frequency changes. PMID:27144230

  4. Vertebral artery aneurysms.

    Directory of Open Access Journals (Sweden)

    Ravi Kumar C

    2000-04-01

    Full Text Available Vertebral artery (VA aneurysms are rare. We present our experience with three cases of VA aneurysms. Two aneurysms were located close to the origin of basilar artery while the third patient had a giant posterior inferior cerebellar artery aneurysm. These aneurysms were operated by the far lateral inferior suboccipital approach with good results.

  5. Retinal artery occlusion

    Science.gov (United States)

    ... artery occlusion; Branch retinal artery occlusion; CRAO; BRAO Images Retina References Sanborn GE, Magargal LE. Arterial obstructive disease ... A.M. Editorial team. Related MedlinePlus Health Topics ... audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among ...

  6. Chorionic plate arterial function is altered in maternal obesity

    OpenAIRE

    Hayward, C.E.; Higgins, L.; Cowley, E.J.; Greenwood, S. l.; Mills, T.A.; Sibley, C. P.; Wareing, M.

    2013-01-01

    Objectives To characterise Chorionic Plate Artery (CPA) function in maternal obesity, and investigate whether leptin exposure reproduces the obese CPA phenotype in normal-BMI women. Study design CPA responses to the thromboxane-A2 mimetic U46619 (pre/post leptin incubation), to the nitric oxide donor sodium nitroprusside (SNP) and the occurrence of tone oscillations (pre/post leptin incubation) were assessed in 46 term placentas from women of normal (18.5–24.9) or obese (>30) Body Mass Index ...

  7. Acute change in vascular tone alters intima-media thickness

    NARCIS (Netherlands)

    Thijssen, D.H.J.; Scholten, R.R.; Munckhof, I.C. van den; Benda, N.M.M.; Green, D.J.; Hopman, M.T.E.

    2011-01-01

    Atherosclerosis is a lifelong process involving artery wall thickening. Increased wall thickness has been widely adopted as a preclinical surrogate marker of atherosclerosis. A prerequisite for such a surrogate marker is that it is a structural characteristic of the vessel wall that is not subject t

  8. Tone-Mapped Mean-Shift Based Environment Map Sampling.

    Science.gov (United States)

    Feng, Wei; Yang, Ying; Wan, Liang; Yu, Changguo

    2016-09-01

    In this paper, we present a novel approach for environment map sampling, which is an effective and pragmatic technique to reduce the computational cost of realistic rendering and get plausible rendering images. The proposed approach exploits the advantage of adaptive mean-shift image clustering with aid of tone-mapping, yielding oversegmented strata that have uniform intensities and capture shapes of light regions. The resulted strata, however, have unbalanced importance metric values for rendering, and the strata number is not user-controlled. To handle these issues, we develop an adaptive split-and-merge scheme that refines the strata and obtains a better balanced strata distribution. Compared to the state-of-the-art methods, our approach achieves comparable and even better rendering quality in terms of SSIM, RMSE and HDRVDP2 image quality metrics. Experimental results further show that our approach is more robust to the variation of viewpoint, environment rotation, and sample number. PMID:26584494

  9. SBS mitigation with multi-tone amplification: a theoretical model

    Science.gov (United States)

    Zeringue, Clint; Dajani, Iyad; Bronder, T. Justin; Shay, Thomas; Robin, Craig

    2008-10-01

    Two approaches to two- and three-tone seeding of high power ytterbium-doped fiber amplifiers are investigated using a symbolic and numerical code that solves a two point boundary problem consisting of a 12×12 system of nonlinear differential equations. Optimization of amplifier action is considered in relation to the two most dominant nonlinear effects: stimulated Brillouin scattering and four-wave mixing. One approach uses a large wavelength separation among the input seed beams, while in the other approach the seeds are separated by precisely twice the Brillouin shift. It is found that for both techniques significant increase in amplifier output can be obtained, although for the latter case a substantial amount of power is generated in the four-wave mixing sidebands.

  10. Tone calibration technique: A digital signaling scheme for mobile applications

    Science.gov (United States)

    Davarian, F.

    1986-01-01

    Residual carrier modulation is conventionally used in a communication link to assist the receiver with signal demodulation and detection. Although suppressed carrier modulation has a slight power advantage over the residual carrier approach in systems enjoying a high level of stability, it lacks sufficient robustness to be used in channels severely contaminated by noise, interference and propagation effects. In mobile links, in particular, the vehicle motion and multipath waveform propagation affect the received carrier in an adverse fashion. A residual carrier scheme that uses a pilot carrier to calibrate a mobile channel against multipath fading anomalies is described. The benefits of this scheme, known as tone calibration technique, are described. A brief study of the system performance in the presence of implementation anomalies is also given.

  11. The Study of Tone and Related Phenomena in an Amazonian Tone Language: Gavião of Rondônia

    Science.gov (United States)

    Moore, Denny; Meyer, Julien

    2014-01-01

    This paper describes the methods used to study the tone and some related phenomena of the language of the Gavião of Rondônia, Brazil, which is part of the Mondé branch of the Tupi family. Whistling of words by indigenous informants was discovered to be a very effective method for obtaining phonetic accuracy in tone and length. Methods were devised…

  12. Responsiveness of muscle tone characteristics to progressive force production.

    Science.gov (United States)

    Mustalampi, Sirpa; Häkkinen, Arja; Kautiainen, Hannu; Weir, Adam; Ylinen, Jari

    2013-01-01

    It is possible to measure muscle tone reliably, quickly and objectively using tonometers although they are not yet widely used. In clinical practice, it may be helpful if clinicians could assess the degree of contraction in different parts of a muscle without having to perform time-consuming electromyography measurements. The purpose of this study was to evaluate the responsiveness of different muscle tone characteristics to progressively increased contraction force of quadriceps muscle. Twenty healthy subjects (mean age 39.9 years, 50% women) volunteered. Using 2 different tonometers various muscle viscoelastic properties were measured. The frequency (hertz), logarithmic decrement, and stiffness (newtons per meter) of damped mechanical oscillation of the muscle tissue and tissue compliance (millijoules) were registered from rectus femoris muscle at rest and 20, 40, 60, 80% of maximal voluntary contraction determined using dynamometry. All the values changed linearly with increasing force level. Compliance, oscillation stiffness, and frequency parameters showed large effect sizes (ESs ≥ 0.8). The standardized respoknse mean for compliance was 5.3 (4.8-5.7) mJ, for oscillation stiffness 1.8 (1.3-2.2) N·m(-1), frequency 1.1 (0.6-1.5) Hz, and decrement -0.6 (-1.0 to -0.2). The results indicate that the compliance and oscillation stiffness parameters showed the highest responsiveness and can thus best detect changes in muscle contraction state. The additional value of using tonometers to measure these properties in clinical practice should be investigated further.

  13. Modèle de diélectrique associant les effets Poole-Frenkel et Maxwell-Wagner

    OpenAIRE

    Pillonnet, Alain; Ongaro, Roger; Garoum, Mohammed

    1992-01-01

    Le modèle présenté associe les effets Poole-Frenkel (PF) et Maxwell-Wagner (MW) dans la détermination de la conductivité équivalente σ d'un diélectrique plan à deux couches. L'effet PF y est introduit sous sa forme usuelle (statistique de Boltzmann), puis sous une forme plus générale (statistique de Fermi-Dirac). Les courbes log σ en fonction du champ électrique $(\\sqrt{F})$ présentent généralement une ou deux parties linéaires, la pente en bas champs étant toujours supérieure à la pente en h...

  14. Les gaz à effet de serre en élevage bovin : évaluation et leviers d'action

    OpenAIRE

    Dollé, Jean-Baptiste; Agabriel, Jacques; Peyraud, Jean-Louis; Faverdin, Philippe; Manneville, Vincent; Raison, Christelle; Gac, Armelle; Le Gall, André

    2011-01-01

    Le contexte environnemental actuel, tant politique (objectifs de réduction des émissions de gaz à effet de serre) que sociétal (information du consommateur), nécessite de préciser les impacts de l'activité d'élevage bovin en matière de changement climatique. L'enjeu est de connaître précisément les niveaux d'émissions de gaz à effet de serre (GES) et de stockage de carbone, des différents modes de production. Pour cela, une évaluation basée sur la méthodologie de l'Analyse du Cycle de Vie (AC...

  15. Effet ventriloque pour des sources sonores variant simultanément en azimut et elévation

    OpenAIRE

    Hendrickx, Etienne; Paquier, Mathieu; Koehl, Vincent; PALACINO, Julian

    2016-01-01

    Lorsque l'on présente a un sujet des stimuli audio et visuel temporellement coïncidents mais spatialement disparates, les sujets perçoivent parfois le stimulus sonore au même endroit que le stimulus visuel. On appelle ce phénomène l'effet ventriloque car il rappelle l'illusion créée par le ventriloque lorsque sa voix semble plutôt provenir de sa marionnette que de sa propre bouche. Cet effet a été très largement étudié en azimut, mais beaucoup moins en élévation. Dans cette étude, des séquenc...

  16. Hemodynamic analysis of arterial pressure oscillations in conscious rats.

    Science.gov (United States)

    Julien, C; Zhang, Z Q; Cerutti, C; Barrès, C

    1995-01-01

    This study examined the contribution of rhythmic fluctuations of regional blood flow and vascular conductance to the genesis of low- (LF, 0.27-0.74 Hz) and high- (HF, 0.76-5 Hz) frequency oscillations of arterial pressure. In conscious 15-week-old male intact (n = 11), guanethidine-sympathectomized (n = 8) and chronically sinoaortic denervated (n = 7) rats, arterial pressure and regional blood flow velocities (pulsed Doppler probes) were simultaneously recorded. Indices of subdiaphragmatic aortic, hindquarters and superior mesenteric conductances were calculated on a beat-to-beat basis over a 60-min period. Spectral power was calculated in the LF and HF bands using a fast Fourier transform algorithm. Transfer function analysis was also performed to calculate coherence and phase between arterial pressure and regional flows and conductances. In the LF band, spectral power of arterial pressure was decreased by approx. 85% in sympathectomized and approx. 54% in sinoaortic denervated rats. In the HF band, spectral power did not differ between the groups. In the three groups of rats, relations between arterial pressure and blood flow were characterized by a significant coherence in the HF band with little or no phase delay (synchronous oscillations). Relations between arterial pressure and vascular conductance were characterized in intact rats by a significant coherence in the LF band and a phase delay tending to pi radians (opposite oscillations), whereas in both sympathectomized and sinoaortic denervated rats, coherence did not reach significance. It is concluded that LF oscillations of arterial pressure are mostly secondary to rhythmic fluctuations in the vasomotor sympathetic tone in several regional circulations. Part of these oscillations originate from the synchronizing influence of the baroreceptor reflex. The study also suggests that the respiratory (HF) oscillations of arterial pressure involve fluctuations in cardiac output of purely mechanical origin. PMID

  17. Interactions of the gasotransmitters contribute to microvascular tone (dysregulation in the preterm neonate.

    Directory of Open Access Journals (Sweden)

    Rebecca M Dyson

    Full Text Available Hydrogen sulphide (H2S, nitric oxide (NO, and carbon monoxide (CO are involved in transitional microvascular tone dysregulation in the preterm infant; however there is conflicting evidence on the interaction of these gasotransmitters, and their overall contribution to the microcirculation in newborns is not known. The aim of this study was to measure the levels of all 3 gasotransmitters, characterise their interrelationships and elucidate their combined effects on microvascular blood flow.90 preterm neonates were studied at 24h postnatal age. Microvascular studies were performed by laser Doppler. Arterial COHb levels (a measure of CO were determined through co-oximetry. NO was measured as nitrate and nitrite in urine. H2S was measured as thiosulphate by liquid chromatography. Relationships between levels of the gasotransmitters and microvascular blood flow were assessed through partial correlation controlling for the influence of gestational age. Structural equation modelling was used to examine the combination of these effects on microvascular blood flow and derive a theoretical model of their interactions.No relationship was observed between NO and CO (p = 0.18, r = 0.18. A positive relationship between NO and H2S (p = 0.008, r = 0.28 and an inverse relationship between CO and H2S (p = 0.01, r = -0.33 exists. Structural equation modelling was used to examine the combination of these effects on microvascular blood flow. The model with the best fit is presented.The relationships between NO and H2S, and CO and H2S may be of importance in the preterm newborn, particularly as NO levels in males are associated with higher H2S levels and higher microvascular blood flow and CO in females appears to convey protection against vascular dysregulation. Here we present a theoretical model of these interactions and their overall effects on microvascular flow in the preterm newborn, upon which future mechanistic studies may be based.

  18. Pulmonary function, cholinergic bronchomotor tone, and cardiac autonomic abnormalities in type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Melo E.

    2003-01-01

    Full Text Available This prospective study analyzed the involvement of the autonomic nervous system in pulmonary and cardiac function by evaluating cardiovascular reflex and its correlation with pulmonary function abnormalities of type 2 diabetic patients. Diabetic patients (N = 17 and healthy subjects (N = 17 were evaluated by 1 pulmonary function tests including spirometry, He-dilution method, N2 washout test, and specific airway conductance (SGaw determined by plethysmography before and after aerosol administration of atropine sulfate, and 2 autonomic cardiovascular activity by the passive tilting test and the magnitude of respiratory sinus arrhythmia (RSA. Basal heart rate was higher in the diabetic group (87.8 ± 11.2 bpm; mean ± SD than in the control group (72.9 ± 7.8 bpm, P<0.05. The increase of heart rate at 5 s of tilting was 11.8 ± 6.5 bpm in diabetic patients and 17.6 ± 6.2 bpm in the control group (P<0.05. Systemic arterial pressure and RSA analysis did not reveal significant differences between groups. Diabetes intragroup analysis revealed two behaviors: 10 patients with close to normal findings and 7 with significant abnormalities in terms of RSA, with the latter subgroup presenting one or more abnormalities in other tests and clear evidence of cardiovascular autonomic dysfunction. End-expiratory flows were significantly lower in diabetic patients than in the control group (P<0.05. Pulmonary function tests before and after atropine administration demonstrated comparable responses by both groups. Type 2 diabetic patients have cardiac autonomic dysfunction that is not associated with bronchomotor tone alterations, probably reflecting a less severe impairment than that of type 1 diabetes mellitus. Yet, a reduction of end-expiratory flow was detected.

  19. Effets Seebeck et Nernst dans les cuprates: Etude de la reconstruction de la surface de Fermi sous champ magnetique intense

    Science.gov (United States)

    Laliberte, Francis

    2010-06-01

    Ce memoire presente des mesures de transport thermoelectrique, les effets Seebeck et Nernst, dans une serie d'echantillons de supraconducteurs a haute temperature critique. Des resultats obtenus recemment au Laboratoire National des Champs Magnetiques Intenses a Grenoble sur La1.7Eu0.2Sr0.1 CuO4, La1.675Eu0.2Sr0.125CuO 4, La1.64Eu0.2Sr0.16CuO4, La1.74Eu0.1Sr0.16CuO4 et La 1.4Nd0.4Sr0.2CuO4 sont analyses. Une attention particuliere est accordee aux equations de la theorie semi-classique du transport et leur validite est verifiee. La procedure experimentale et les materiaux utilises pour concevoir les montages de mesures sont expliques en detail. Enfin, un chapitre est dedie a l'explication et l'interpretation des resultats de transport thermoelectrique sur YBa2Cu3O6+delta publies au cours de l'hiver 2010 dans les revues Nature et Physical Review Letters. Les donnees d'effet Seebeck dans les echantillons de La 1.8-x,Eu0.2SrxCuO 4, ou un changement de signe est observe, permettent de conclure a la presence d'une poche d'electrons dans la surface de Fermi qui domine le transport a basse temperature dans la region sous-dopee du diagramme de phase. Cette conclusion est similaire a celle obtenue par des mesures d'effet Hall dans YBa 2Cu3O6+delta et elle cadre bien dans un scenario de reconstruction de la surface de Fermi. Les donnees d'effet Nernst recueillies indiquent que la contribution des fluctuations supraconductrices est limitee a un modeste intervalle de temperature au-dessus de la temperature critique.

  20. [Upper extremity arterial diseases].

    Science.gov (United States)

    Becker, F

    2007-02-01

    Compared to lower limb arterial diseases, upper limb arterial diseases look rare, heterogeneous with various etiologies and a rather vague clinical picture, but with a negligible risk of amputation. Almost all types of arterial diseases can be present in the upper limb, but the anatomical and hemodynamic conditions particular to the upper limb often confuse the issue. Thus, atherosclerosis affects mainly the subclavian artery in its proximal segment where the potential of collateral pathway is high making the symptomatic forms not very frequent whereas the prevalence of subclavian artery stenosis or occlusion is relatively high. The clinical examination and the etiologies are discussed according to the clinical, anatomical and hemodynamic context.

  1. Contrasting the effects of duration and number of syllables on the perceptual normalization of lexical tones

    Science.gov (United States)

    Ciocca, Valter; Francis, Alexander L.; Yau, Teresa S.-K.

    2001-05-01

    In tonal languages, syllabic fundamental frequency (F0) patterns (``lexical tones'') convey lexical meaning. Listeners need to relate such pitch patterns to the pitch range of a speaker (``tone normalization'') to accurately identify lexical tones. This study investigated the amount of tonal information required to perform tone normalization. A target CV syllable, perceived as either a high level, a low level, or a mid level Cantonese tone, was preceded by a four-syllable carrier sentence whose F0 was shifted (1 semitone), or not shifted. Four conditions were obtained by gating one, two, three, or four syllables from the onset of the target. Presentation rate (normal versus fast) was set such that the duration of the one, two, and three syllable conditions (normal carrier) was equal to that of the two, three, and four syllable conditions (fast carrier). Results suggest that tone normalization is largely accomplished within 250 ms or so prior to target onset, independent of the number of syllables; additional tonal information produces a relatively small increase in tone normalization. Implications for models of lexical tone normalization will be discussed. [Work supported by the RGC of the Hong Kong SAR, Project No. HKU 7193/00H.

  2. Loudness of brief tones in listeners with normal hearing and sensorineural hearing loss

    DEFF Research Database (Denmark)

    Buus, Søren; Florentine, Mary; Poulsen, Torben

    1997-01-01

    To investigate how hearing loss affects the loudness of brief tones, loudness matches between 5- and 200-ms tones were obtained as a function of level. Loudness functions derived from these data indicated that the gain required to restore loudness usually is the same for short and long sounds....

  3. A Model of Mandarin Tone Categories--A Study of Perception and Production

    Science.gov (United States)

    Yang, Bei

    2010-01-01

    The current study lays the groundwork for a model of Mandarin tones based on both native speakers' and non-native speakers' perception and production. It demonstrates that there is variability in non-native speakers' tone productions and that there are differences in the perceptual boundaries in native speakers and non-native speakers. There…

  4. Factors Affecting the Production of Vietnamese Tones: A Study of American Learners

    Science.gov (United States)

    Nguyen, Hanh thi; Macken, Marlys A.

    2008-01-01

    This study investigates factors that affect the accuracy of tone production by American students of Vietnamese as a second language (L2). Nine hypotheses are examined, each of which isolates a factor expected to affect production accuracy: (a) task type, (b) the position of a tone in a clause, (c) discourse distance between a model provided by a…

  5. Production and Perception of Mandarin Tone in Adults with Cerebral Palsy

    Science.gov (United States)

    Jeng, Jing-Yi; Weismer, Gary; Kent, Ray D.

    2006-01-01

    The primary objective of the present study was to document tone production and intelligibility deficits in Mandarin-speaking persons with cerebral palsy (CP). Spastic, athetoid, and mixed types of CP were studied, along with a control group, to investigate the possibility of tone production and intelligibility deficits that were differentially…

  6. The Utility of Chinese Tone Processing Skill in Detecting Children with English Reading Disabilities

    Science.gov (United States)

    Anderson, Alida; Wang, Min

    2012-01-01

    The utility of Chinese tone processing skill in detecting children with English reading difficulties was examined through differences in a Chinese tone experimental task between a group of native English-speaking children with reading disabilities (RD) and a comparison group of children with normal reading development (NRD). General auditory…

  7. Tone and Syntax in Rutooro, a Toneless Bantu Language of Western Uganda

    Science.gov (United States)

    Kaji, Shigeki

    2009-01-01

    This paper explores the interaction of tone and syntax in Rutooro, a Bantu language of Western Uganda. Rutooro has lost its lexical tone but retains a phrasally defined high pitch that appears on the penultimate syllable--the default position in Bantu. This high pitch can work grammatically and in fact distinguishes between the noun phrase vs.…

  8. Neural Control of Rising and Falling Tones in Mandarin Speakers Who Stutter

    Science.gov (United States)

    Howell, Peter; Jiang, Jing; Peng, Danling; Lu, Chunming

    2012-01-01

    Neural control of rising and falling tones in Mandarin people who stutter (PWS) was examined by comparing with that which occurs in fluent speakers [Howell, Jiang, Peng, and Lu (2012). Neural control of fundamental frequency rise and fall in Mandarin tones. "Brain and Language, 121"(1), 35-46]. Nine PWS and nine controls were scanned. Functional…

  9. Newborn Pain Cries and Vagal Tone: Parallel Changes in Response to Circumcision.

    Science.gov (United States)

    Porter, Fran Lang; And Others

    1988-01-01

    The relation between cry acoustics and vagal tone in normal, healthy newborns undergoing an acutely stressful event was examined. Vagal tone was significantly reduced during the stressful event and was paralleled by significant increases in the pitch of the infants' cries. (PCB)

  10. Musically Tone-Deaf Individuals Have Difficulty Discriminating Intonation Contours Extracted from Speech

    Science.gov (United States)

    Patel, Aniruddh D.; Foxton, Jessica M.; Griffiths, Timothy D.

    2005-01-01

    Musically tone-deaf individuals have psychophysical deficits in detecting pitch changes, yet their discrimination of intonation contours in speech appears to be normal. One hypothesis for this dissociation is that intonation contours use coarse pitch contrasts which exceed the pitch-change detection thresholds of tone-deaf individuals (Peretz &…

  11. Skin-Tone Preferences and Self-Representation in Hispanic Children

    Science.gov (United States)

    Kaufman, Erin A.; Wiese, Deborah L.

    2012-01-01

    Skin-tone preferences and colourism within Hispanic children have been largely unexamined in the psychological literature. The objectives of the current study were to investigate Hispanic children's skin-tone preferences and the effect of assessor race and ethnicity on those preferences. To carry out the study, Clark and Clark's colouring task was…

  12. Positive affective tone and team performance: The moderating role of collective emotional skills.

    Science.gov (United States)

    Collins, Amy L; Jordan, Peter J; Lawrence, Sandra A; Troth, Ashlea C

    2016-01-01

    Research on affect as a group-level phenomenon has shown that over time, individual members within a group become highly similar in their affect (i.e., members experience and display similar emotions and moods), and often become similar enough that the aggregation of individuals' affect can meaningfully represent the "affective tone" of the group. It is generally assumed that a more positive affective tone will lead to better team performance. We challenge the conclusion that positive affective tone is always good for team performance, suggesting that the relationship between positive affective tone and team performance is subject to moderating influences. Across two studies, we demonstrate that the self-reported collective emotional skills of team members play a crucial role in determining whether positive affective tone is beneficial or detrimental to team performance. Implications for theory and practice are discussed. PMID:26208085

  13. On the design of tone-free ΣΔ modulators

    DEFF Research Database (Denmark)

    Risbo, Lars

    1995-01-01

    Traditional one-bit ΣΔ modulators used for A/D and D/A conversion produce very predominant tones near half the sample rate which might intermodulate in the analog converter section and cause in-band tones. This paper demonstrates how the use of chaos can substitute dither as a means for extinguis......Traditional one-bit ΣΔ modulators used for A/D and D/A conversion produce very predominant tones near half the sample rate which might intermodulate in the analog converter section and cause in-band tones. This paper demonstrates how the use of chaos can substitute dither as a means...... for extinguishing these tones. Especially, modulator feedback filters derived from noise transfer functions having an all-pass term seem very promising...

  14. Chronic intrauterine pulmonary hypertension increases main pulmonary artery stiffness and adventitial remodeling in fetal sheep

    OpenAIRE

    Dodson, R. Blair; Morgan, Matthew R.; Galambos, Csaba; Hunter, Kendall S.; Abman, Steven H.

    2014-01-01

    Persistent pulmonary hypertension of the newborn (PPHN) is a clinical syndrome that is characterized by high pulmonary vascular resistance due to changes in lung vascular growth, structure, and tone. PPHN has been primarily considered as a disease of the small pulmonary arteries (PA), but proximal vascular stiffness has been shown to be an important predictor of morbidity and mortality in other diseases associated with pulmonary hypertension (PH). The objective of this study is to characteriz...

  15. Endothelial 5-HT receptors mediate relaxation of porcine pulmonary arteries in response to ergotamine and dihydroergotamine.

    OpenAIRE

    Glusa, E; Roos, A. (Anna)

    1996-01-01

    1. The aim of the present study was to investigate whether antimigraine ergot compounds may act at endothelial 5-hydroxytryptamine (5-HT) receptors which trigger the release of endothelium-derived relaxing factor (EDRF). Changes in tone of porcine isolated pulmonary arteries were measured isometrically. The integrity of the endothelium was assessed by the bradykinin-induced relaxation of prostaglandin F2 alpha (PGF2 alpha, 3 microM)-precontracted vessels. 2. The ergot derivatives ergotamine, ...

  16. Acute occlusion of the left subclavian artery with artery dissection

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Subclavian steal syndrome is cerebral or brain stem ischemia resulting from diversion of blood flow from the basilar artery to the subclavian artery, which is caused by occlusive disease of either the subclavian artery or the innominate artery before they branch off at the vertebral artery. In the patients with subclavian steal syndrome the subclavian artery is fed by retrograde flow from the vertebral artery via the carotids and the circle of Willis.

  17. Effet getter dans des plaquettes de silicium multicristallin par diffusion de phosphore

    Science.gov (United States)

    Perichaud, I.; Martinuzzi, S.

    1992-03-01

    The external gettering effect by phosphorus diffusion is used to improve the electrical properties of multicrystalline silicon wafers. After diffusion at 900 °C for 4 h it was found that the effective diffusion lengths L_n of minority carriers achieve or overpass the thickness of the wafers. After diffusion at 850 °C for 4 h the improvements are less marked and hydrogenation is needed to obtain the same increase of L_n. SIMS analysis indicates that the gettered impurities are essentially iron, copper and nickel. Some restricted regions of the wafers are only poorly improved. It was found after chemical etching that these regions contain a high density of subgrain boundaries. The mechanism of the gettering effect used in this work is proposed, taking in account dissolved impurities in the grains and impurities segregated by dislocations. The additivity of the hydrogenation effect might be understood by the neutralisation of the recombination centers related to oxygen atoms segregated by the dislocations. L'effet getter externe par diffusion de phosphore est utilisé pour améliorer les propriétés électriques de plaquettes de silicium multicristallin. Après 4h à 900°C les longueurs de diffusion des porteurs minoritaires atteignent ou dépassent l'épaisseur des plaquettes. Après 4h à 850°C, les augmentations sont moins spectaculaires et une hydrogénation du matériau est nécessaire pour obtenir un résultat comparable au précédent. Les analyses SIMS indiquent que les impuretés extraites sont surtout du fer, du cuivre et du nickel. Certaines régions du matériau, d'extension limitée, sont toutefois peu améliorées. Elles sont caractérisées par la présence d'un réseau très dense de sous-joints. Une interprétation du mécanisme de l'effet getter observé est proposée faisant intervenir les impuretés métalliques dissoutes et celles ségrégées par les dislocations. L'additivité de l'action de l'hydrogène s'expliquerait par la neutralisation

  18. Effets de la pollution de l’air sur la santé

    Science.gov (United States)

    Abelsohn, Alan; Stieb, Dave M.

    2011-01-01

    Résumé Objectif Faire connaître aux médecins de famille les effets de la pollution atmosphérique sur la santé et indiquer quels conseils donner aux patients vulnérables pour qu’ils soient moins exposés. Sources de l’information On a consulté MEDLINE à l’aide des termes relatifs à la pollution atmosphérique et à ses effets indésirables. On a révisé les articles en anglais publiés entre janvier 2008 et décembre 2009. La plupart des études contenaient des preuves de niveau II. Principal message Au Canada, la pollution de l’air extérieur cause une morbidité et une mortalité importantes. Elle peut affecter le système respiratoire (exacerbation de l’asthme et de la maladie pulmonaire obstructive chronique) et le système cardiovasculaire (déclencher l’arythmie, l’insuffisance cardiaque et les AVC). La cote air santé (CAS) est un nouvel outil de communication mis au point par Santé Canada et Environnement Canada qui indique sur une échelle de 1 à 10, le risque pour la santé causé par la pollution atmosphérique. La CAS est largement diffusée dans les médias et cet outil pourrait être utile au médecin de famille pour inciter les patients à haut risque (comme ceux qui souffrent d’asthme, de maladie pulmonaire obstructive chronique ou d’insuffisance cardiaque) à réduire leur exposition à la pollution atmosphérique. Conclusion Le médecin de famille peut se servir de la CAS et de ses messages sur la santé pour enseigner aux asthmatiques et aux autres patients à risque élevé la façon de réduire les risques pour la santé causés par la pollution atmosphérique.

  19. Effet du flambage sur les pipes en composite stratifiés munis d’entailles

    Directory of Open Access Journals (Sweden)

    Chenine Halima

    2014-04-01

    Full Text Available Dans l’industrie (aéronautiques, automobiles, … les composites stratifiés se sont imposés pour la fabrication des pièces de structures primaires, grâce à leurs performances, leur qualité, légèreté et souplesse de forme. Cependant l’utilisation de ces matériaux est assujettie à la connaissance de leur comportement mécanique en statique comme en dynamique et également à la possibilité de le simuler. En effet, les matériaux composites ont un comportement particulier, et ceci est du essentiellement à deux facteurs. Le premier facteur résulte du comportement anisotrope du matériau utilisé dans la couche. Le deuxième facteur dérive de la stratification qui consiste à l’empilement de plusieurs couches, ce qui favorise l’effet de cisaillement transversal. Les structures minces en composites qui sont abondamment utilisées, deviennent instables lorsqu'elles sont sollicitées à des chargements de nature mécanique ou thermique conduisant au flambement. La principale cause de ce phénomène complexe, est le caractère aléatoire des imperfections initiales (en termes de géométrie, de matériau, ou de conditions aux limites de la structure. Dans ce papier, l’analyse du flambage a été effectuée sur des pipes en composite stratifiés avec et sans entaille carrée, en ayant recours a la simulation numérique a l’aide de la MEF. Le pipe stratifié comporte plusieurs couches alternées de la manière suivante (Θ/-Θ5. La résistance au flambage des pipes est mise en évidence en fonction de l’orientation des fibres. Les résultats montrent que la charge de flambage est plus grande pour les plus petits diamètres, et surtout pour les orientations (20°/-20°, ce qui augmente le risque de la rupture. Et pour la distribution des contraintes de Von mises, la concentration la plus importante est pour les orientations (20°/-20° et les plus faibles au niveau de l’orientation 90°. Donc l’ampleur des contraintes d

  20. Bilateral accessory thoracodorsal artery.

    Science.gov (United States)

    Natsis, Konstantinos; Totlis, Trifon; Tsikaras, Prokopios; Skandalakis, Panagiotis

    2006-09-01

    The subscapular artery arises from the third part of the axillary artery and gives off the circumflex scapular and the thoracodorsal arteries. Although anatomical variations of the axillary artery are very common, the existence of a unilateral accessory thoracodorsal artery has been described in the literature only once. There are no reports of bilateral accessory thoracodorsal artery, in the literature. In the present study, a bilateral accessory thoracodorsal artery, originating on either side of the third part of the axillary artery, is described in a 68-year-old female cadaver. All the other branches of the axillary artery had a typical origin, course, distribution and termination. This extremely rare anatomical variation apart from the anatomical importance also has clinical significance for surgeons in this area. Especially, during the dissection or mobilization of the latissimus dorsi that is partly used for coverage problems in many regions of the body and also in dynamic cardiomyoplasty, any iatrogenic injury of this accessory artery may result in ischemia and functional loss of the graft.

  1. Spirit Examines Light-Toned 'Halley' (False Color)

    Science.gov (United States)

    2006-01-01

    Stretching along 'Low Ridge' in front of the winter haven for NASA's Mars Exploration Rover Spirit are several continuous rock layers that make up the ridge. Some of these layers form fins that stick out from the other rocks in a way that suggests that they are resistant to erosion. Spirit is currently straddling one of these fin-like layers and can reach a small bit of light-toned material that might be a broken bit of it. Informally named 'Halley,' this rock was broken by Spirit's wheels when the rover drove over it. The first analyses of Halley showed it to be unusual in composition, containing a lot of the minor element zinc relative to the soil around it and having much of its iron tied up in the mineral hematite. When scientists again placed the scientific instruments on Spirit's robotic arm on a particularly bright-looking part of Halley, they found that the chemical composition of the bright spots was suggestive of a calcium sulfate mineral. Bright soils that Spirit has examined earlier in the mission contain iron sulfate. This discovery raises new questions for the science team: Why is the sulfate mineralogy here different? Did Halley and the fin material form by water percolating through the layered rocks of Low Ridge? When did the chemical alteration of this rock occur? Spirit will continue to work on Halley and other light-toned materials along Low Ridge in the coming months to try to answer these questions. Spirit took this red-green-blue composite image with the panoramic camera on the rover's 820th sol, or Martian day, of exploring Mars (April 24, 2006). The image is presented in false color to emphasize differences among materials in the rocks and soil. It combines frames taken through the camera's 750-nanometer, 530-nanometer, and 430-nanometer filters. The middle of the imaged area has dark basaltic sand. Spirit's wheel track is at the left edge of the frame. Just to the right of the wheel track in the lower left are two types of brighter material

  2. Comportement instationnaire des thermoéléments à effet Peltier multi-étages

    Science.gov (United States)

    Monchoux, F.; Zély, D.; Cordier, A.

    1995-01-01

    The analysis of thermoelectric phenomena is possible based on non-equilibrium thermodynamics. Integration of the thermal balance equation leads to an analytical solution for the non-stationnary behaviour. The influence to Thomson effect is commmented. The model, introduced in the complete software TRNSYS, permits the modelling of complex systems including such elements in their thermal regulation. La thermodynamique des processus irréversibles permet l'analyse des phénomènes thermoélectriques. Par intégration de l'équation de bilan thermique, on a obtenu une solution analytique pour le régime non stationnaire donnant la température en tous points et le flux absorbé. On a analysé l'influence de l'effet Thomson. Le modèle a été inclu dans le code plus général TRNSYS qui permet la modélisation de systèmes complexes.

  3. Angioplasty and stent placement - peripheral arteries - discharge

    Science.gov (United States)

    Percutaneous transluminal angioplasty - peripheral artery - discharge; PTA - peripheral artery - discharge; Angioplasty - peripheral artery - discharge; Balloon angioplasty - peripheral artery- discharge; PAD - PTA ...

  4. Effects of Temporal Sequencing and Auditory Discrimination on Children's Memory Patterns for Tones, Numbers, and Nonsense Words

    Science.gov (United States)

    Gromko, Joyce Eastlund; Hansen, Dee; Tortora, Anne Halloran; Higgins, Daniel; Boccia, Eric

    2009-01-01

    The purpose of this study was to determine whether children's recall of tones, numbers, and words was supported by a common temporal sequencing mechanism; whether children's patterns of memory for tones, numbers, and nonsense words were the same despite differences in symbol systems; and whether children's recall of tones, numbers, and nonsense…

  5. Tone classification of syllable-segmented Thai speech based on multilayer perception

    Science.gov (United States)

    Satravaha, Nuttavudh; Klinkhachorn, Powsiri; Lass, Norman

    2002-05-01

    Thai is a monosyllabic tonal language that uses tone to convey lexical information about the meaning of a syllable. Thus to completely recognize a spoken Thai syllable, a speech recognition system not only has to recognize a base syllable but also must correctly identify a tone. Hence, tone classification of Thai speech is an essential part of a Thai speech recognition system. Thai has five distinctive tones (``mid,'' ``low,'' ``falling,'' ``high,'' and ``rising'') and each tone is represented by a single fundamental frequency (F0) pattern. However, several factors, including tonal coarticulation, stress, intonation, and speaker variability, affect the F0 pattern of a syllable in continuous Thai speech. In this study, an efficient method for tone classification of syllable-segmented Thai speech, which incorporates the effects of tonal coarticulation, stress, and intonation, as well as a method to perform automatic syllable segmentation, were developed. Acoustic parameters were used as the main discriminating parameters. The F0 contour of a segmented syllable was normalized by using a z-score transformation before being presented to a tone classifier. The proposed system was evaluated on 920 test utterances spoken by 8 speakers. A recognition rate of 91.36% was achieved by the proposed system.

  6. Effects of native language experience on perceptual learning of Cantonese lexical tones

    Science.gov (United States)

    Francis, Alexander L.; Ciocca, Valter; Ma, Lian

    2001-05-01

    In a tonal language syllabic pitch patterns contribute to lexical meaning. Perceptual assimilation models of cross-language perception predict speakers of another tonal language should assimilate Cantonese lexical tones to native tonal categories, affecting identification, discrimination and acquisition. For nontonal language speakers, two possibilities exist. If pitch information is ignored, vowels with different tones should assimilate to the same native category, lowering performance. If tonal information is attended but unused in native categorization, Cantonese tones could be nonassimilable and therefore easily discriminated, and possibly easily identified or learned. Here, native speakers of Mandarin Chinese and American English were trained to identify Cantonese words differing in lexical tone. Discrimination and identification were tested before and after training. Both groups initially performed well on upper register tones (high level, high rising, mid level) and poorly on lower (low falling, low level, low rising). Mandarin listeners improved most at identifying low falling tones; English listeners improved most on low level and low rising tones. Training primarily appeared to improve listeners' ability to make categorical decisions based on direction of pitch change, a feature reportedly under-attended by English speakers, but preferred by Mandarin speakers. [Work supported by research funding from The University of Hong Kong.

  7. Numerical Simulation of the Generation of Axisymmetric Mode Jet Screech Tones

    Science.gov (United States)

    Shen, Hao; Tam, Christopher K. W.

    1998-01-01

    An imperfectly expanded supersonic jet, invariably, radiates both broadband noise and discrete frequency sound called screech tones. Screech tones are known to be generated by a feedback loop driven by the large scale instability waves of the jet flow. Inside the jet plume is a quasi-periodic shock cell structure. The interaction of the instability waves and the shock cell structure, as the former propagates through the latter, is responsible for the generation of the tones. Presently, there are formulas that can predict the tone frequency fairly accurately. However, there is no known way to predict the screech tone intensity. In this work, the screech phenomenon of an axisymmetric jet at low supersonic Mach number is reproduced by numerical simulation. The computed mean velocity profiles and the shock cell pressure distribution of the jet are found to be in good agreement with experimental measurements. The same is true with the simulated screech frequency. Calculated screech tone intensity and directivity at selected jet Mach number are reported in this paper. The present results demonstrate that numerical simulation using computational aeroacoustics methods offers not only a reliable way to determine the screech tone intensity and directivity but also an opportunity to study the physics and detailed mechanisms of the phenomenon by an entirely new approach.

  8. Training for learning Mandarin tones: A comparison of production and perceptual training

    Science.gov (United States)

    Wang, Xinchun

    2005-04-01

    Mandarin Chinese lexical tones pose difficulties for non-native speakers whose first languages contrast or do not contrast lexical tones. In this study, both tone language and non-tone language speaking learners of Mandarin Chinese were trained for three weeks to identify the four Mandarin lexical tones. One group took the production training with both visual and audio feedback using Kay Sona Speech II software. The target tones produced by native Mandarin speakers were played back through a pair of headphones and the pitch contours of the target tones were displayed on the computer screen on the top window to be compared with the trainees productions which appear in real time in the bottom window. Another group of participants took the perceptual training only with four-way forced choice identification tasks with immediate feedback. The same training tokens were used in both training modes. Pretest and post test data in perception and production were collected from both groups and were compared for effectiveness of training procedures.

  9. Spoken word recognition in early childhood: Comparative effects of vowel, consonant and lexical tone variation.

    Science.gov (United States)

    Singh, Leher; Goh, Hwee Hwee; Wewalaarachchi, Thilanga D

    2015-09-01

    The majority of the world's languages exploit consonants, vowels and lexical tones to contrast the meanings of individual words. However, the majority of experimental research on early language development focuses on consonant-vowel languages. In the present study, the role of consonants, vowels and lexical tones in emergent word knowledge are directly compared in toddlers (2.5-3.5 years) and preschoolers (4-5 years) who were bilingual native learners of a consonant-vowel-tone language (Mandarin Chinese). Using a preferential looking paradigm, participants were presented with correct pronunciations and consonantal, vowel, and tonal variations of known words. Responses to each type of variation were assessed via gaze fixations to a visual target. When their labels were correctly pronounced, visual targets were reliably identified at both age groups. However, in toddlers, there was a high degree of sensitivity to mispronunciations due to variation in lexical tones relative to those due to consonants and vowels. This pattern was reversed in preschoolers, who were more sensitive to consonant and vowel variation than to tone variation. Findings are discussed in terms of properties of tones, vowels and consonants and the respective role of each source of variation in tone languages. PMID:26010558

  10. Development of low postural tone compensatory patterns in children - theoretical basis.

    Science.gov (United States)

    Gogola, Anna; Saulicz, Edward; Kuszewski, Michał; Matyja, Małgorzata; Myśliwiec, Andrzej

    2014-01-01

    Neurological literature indicates the existence of children with low postural tone without association with central nervous system damage. This fact induces to think about mechanisms, which allow these children to maintain upright posture. There is a suspicion that compensatory mechanism included in this process, enables to achieve upright posture, but at expense of body posture quality. Observations of children's developmental stages caused determination of some postural tone area, which comprise both children with normotonia and with low postural tone without characteristics of central nervous system (CNS) damage. Set of specific qualities allows determination of two types of low postural tone: spastoidal and atetoidal type. Spastoidal type is characterized by deep trunk muscles (local) low postural tone compensated by excessive tension of superficial muscles (global). Atetoidal type includes children with low postural tone in both deep and superficial muscles. At inefficient active subsystem, verticalization proceeds at excessive use of passive subsystem qualities, that is meniscus, ligament, bone shape, and muscles passive features. From neurodevelopmental point of view compensatory mechanisms can be used in children with low postural tone in order to achieve upright posture, but at expense of body posture quality. PMID:25182403

  11. Discrete tone noise on two-dimensional wing. Active control for discrete tone; Nijigen seishiyoku kara hasseisuru risan shuhasu soon no kenkyu. Risan shuhasu soon no nodo seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, S. [Mitsubishi Electric Corp., Tokyo (Japan); Akishita, S. [Ritsumeikan University, Kyoto (Japan). Faculty of Science and Engineering

    1996-01-25

    The active noise control of discrete tones generated in a uniform jet flow on a two-dimensional wing was investigated. Discrete tone noise is generated by a self-excited feedback loop formed by the acoustic field and the unstable boundary layer. In this work, we conducted an active control experiment using a flap driven by piezoceramic levers, which can vibrate with a phase delayed from the velocity fluctuation signal on the suction side. When the flap motion lags the pressure fluctuation at the trailing edge with a phase angle of 180 degrees, it was found that the discrete tone noise was reduced by a maximum of about 7 dB, the flow fluctuation intensities in the boundary layer on the suction side were reduced by about half, and the correlation area of the flow fluctuation at the trailing edge decreased. This confirms that discrete tone generation is caused by the feedback loop and that the discrete tone generation is actively reduced by trailing edge control. 10 refs., 14 figs.

  12. Hand proximity facilitates spatial discrimination of auditory tones

    Directory of Open Access Journals (Sweden)

    Philip eTseng

    2014-06-01

    Full Text Available The effect of hand proximity on vision and visual attention has been well documented. In this study we tested whether such effect(s would also be present in the auditory modality. With hands placed either near or away from the audio sources, participants performed an auditory-spatial discrimination (Exp 1: left or right side, pitch discrimination (Exp 2: high, med, or low tone, and spatial-plus-pitch (Exp 3: left or right; high, med, or low discrimination task. In Exp 1, when hands were away from the audio source, participants consistently responded faster with their right hand regardless of stimulus location. This right hand advantage, however, disappeared in the hands-near condition because of a significant improvement in left hand’s reaction time. No effect of hand proximity was found in Exp 2 or 3, where a choice reaction time task requiring pitch discrimination was used. Together, these results suggest that the effect of hand proximity is not exclusive to vision alone, but is also present in audition, though in a much weaker form. Most important, these findings provide evidence from auditory attention that supports the multimodal account originally raised by Reed et al. in 2006.

  13. Sympathetic Tone Induced by High Acoustic Tempo Requires Fast Respiration.

    Science.gov (United States)

    Watanabe, Ken; Ooishi, Yuuki; Kashino, Makio

    2015-01-01

    Many studies have revealed the influences of music, and particularly its tempo, on the autonomic nervous system (ANS) and respiration patterns. Since there is the interaction between the ANS and the respiratory system, namely sympatho-respiratory coupling, it is possible that the effect of musical tempo on the ANS is modulated by the respiratory system. Therefore, we investigated the effects of the relationship between musical tempo and respiratory rate on the ANS. Fifty-two healthy people aged 18-35 years participated in this study. Their respiratory rates were controlled by using a silent electronic metronome and they listened to simple drum sounds with a constant tempo. We varied the respiratory rate-acoustic tempo combination. The respiratory rate was controlled at 15 or 20 cycles per minute (CPM) and the acoustic tempo was 60 or 80 beats per minute (BPM) or the environment was silent. Electrocardiograms and an elastic chest band were used to measure the heart rate and respiratory rate, respectively. The mean heart rate and heart rate variability (HRV) were regarded as indices of ANS activity. We observed a significant increase in the mean heart rate and the low (0.04-0.15 Hz) to high (0.15-0.40 Hz) frequency ratio of HRV, only when the respiratory rate was controlled at 20 CPM and the acoustic tempo was 80 BPM. We suggest that the effect of acoustic tempo on the sympathetic tone is modulated by the respiratory system. PMID:26284521

  14. Sympathetic Tone Induced by High Acoustic Tempo Requires Fast Respiration.

    Directory of Open Access Journals (Sweden)

    Ken Watanabe

    Full Text Available Many studies have revealed the influences of music, and particularly its tempo, on the autonomic nervous system (ANS and respiration patterns. Since there is the interaction between the ANS and the respiratory system, namely sympatho-respiratory coupling, it is possible that the effect of musical tempo on the ANS is modulated by the respiratory system. Therefore, we investigated the effects of the relationship between musical tempo and respiratory rate on the ANS. Fifty-two healthy people aged 18-35 years participated in this study. Their respiratory rates were controlled by using a silent electronic metronome and they listened to simple drum sounds with a constant tempo. We varied the respiratory rate-acoustic tempo combination. The respiratory rate was controlled at 15 or 20 cycles per minute (CPM and the acoustic tempo was 60 or 80 beats per minute (BPM or the environment was silent. Electrocardiograms and an elastic chest band were used to measure the heart rate and respiratory rate, respectively. The mean heart rate and heart rate variability (HRV were regarded as indices of ANS activity. We observed a significant increase in the mean heart rate and the low (0.04-0.15 Hz to high (0.15-0.40 Hz frequency ratio of HRV, only when the respiratory rate was controlled at 20 CPM and the acoustic tempo was 80 BPM. We suggest that the effect of acoustic tempo on the sympathetic tone is modulated by the respiratory system.

  15. Spectral decomposition of single-tone-driven quantum phase modulation

    Energy Technology Data Exchange (ETDEWEB)

    Capmany, Jose [ITEAM Research Institute, Univ. Politecnica de Valencia, 46022 Valencia (Spain); Fernandez-Pousa, Carlos R, E-mail: c.pousa@umh.es [Signal Theory and Communications, Department of Physics and Computer Science, Univ. Miguel Hernandez, 03202 Elche (Spain)

    2011-02-14

    Electro-optic phase modulators driven by a single radio-frequency tone {Omega} can be described at the quantum level as scattering devices where input single-mode radiation undergoes energy changes in multiples of {h_bar}{Omega}. In this paper, we study the spectral representation of the unitary, multimode scattering operator describing these devices. The eigenvalue equation, phase modulation being a process preserving the photon number, is solved at each subspace with definite number of photons. In the one-photon subspace F{sub 1}, the problem is equivalent to the computation of the continuous spectrum of the Susskind-Glogower cosine operator of the harmonic oscillator. Using this analogy, the spectral decomposition in F{sub 1} is constructed and shown to be equivalent to the usual Fock-space representation. The result is then generalized to arbitrary N-photon subspaces, where eigenvectors are symmetrized combinations of N one-photon eigenvectors and the continuous spectrum spans the entire unit circle. Approximate normalizable one-photon eigenstates are constructed in terms of London phase states truncated to optical bands. Finally, we show that synchronous ultrashort pulse trains represent classical field configurations with the same structure as these approximate eigenstates, and that they can be considered as approximate eigenvectors of the classical formulation of phase modulation.

  16. Popliteal artery entrapment syndrome.

    LENUS (Irish Health Repository)

    O'Leary, D P

    2010-01-01

    Popliteal artery entrapment syndrome is a rare abnormality of the anatomical relationship between the popliteal artery and adjacent muscles or fibrous bands in the popliteal fossa. The following is a case report of a 19 year old female, in whom popliteal artery entrapment syndrome was diagnosed, and successfully treated surgically. A review of literature is also presented and provides details on how PAES is classified, diagnosed both clinically and radiologically, and treated surgically.

  17. [Popliteal artery entrapment syndrome].

    Science.gov (United States)

    Musumeci, S; Iuppa, A; Beneventano, G; Rinella, P; Mammano, M; Cinquegrani, E

    1986-12-15

    Trapped popliteal artery syndrome is relatively uncommon: the literature reports some 60 cases. The clinical picture is linked to compression of the popliteal artery by the gastrocnemius as it contracts, thus distorting the arterial route. The result is an interruption in the blood flow distally to the area involved due to stenosis of the blood vessel that is at first functional but becomes organic. PMID:3808379

  18. Celiac Artery Compression Syndrome

    Directory of Open Access Journals (Sweden)

    Mohammed Muqeetadnan

    2013-01-01

    Full Text Available Celiac artery compression syndrome is a rare disorder characterized by episodic abdominal pain and weight loss. It is the result of external compression of celiac artery by the median arcuate ligament. We present a case of celiac artery compression syndrome in a 57-year-old male with severe postprandial abdominal pain and 30-pound weight loss. The patient eventually responded well to surgical division of the median arcuate ligament by laparoscopy.

  19. Heritability of cilioretinal arteries

    DEFF Research Database (Denmark)

    Taarnhøj, Nina Charlotte; Munch, Inger C; Kyvik, Kirsten O;

    2005-01-01

    of healthy monozygotic and dizygotic twins were examined using digital fundus photography and visual assessment of grayscale fundus photographs and color transparencies to detect the presence of cilioretinal arteries. RESULTS: Cilioretinal arteries were present in 45.1% of participants and 28.8% of eyes....... The majority of cilioretinal arteries, 88.2%, were located temporally, and 11.8% were located nasally. Monozygotic twins had higher concordance rates for cilioretinal arteries than dizygotic twins. Tetrachoric correlations and Mantel-Haenszel odds ratios demonstrated statistically significant evidence...

  20. Peripheral artery disease - legs

    Science.gov (United States)

    ... if they have a history of: Abnormal cholesterol Diabetes Heart disease (coronary artery disease) High blood pressure ( hypertension ) Kidney disease involving hemodialysis Smoking Stroke ( cerebrovascular disease )

  1. Right Coronary Artery Arising from Circumflex Artery: A Case of Single Coronary Artery Anomaly

    Directory of Open Access Journals (Sweden)

    Hekim Karapınar

    2013-08-01

    Full Text Available Coronary artery anomalies could be cause of conflicts for catheterization, especially, in the setting of acute coronary syndrome. We described a case of rare single coronary anomaly which the right coronary artery arisen from terminal part of left circumflex artery. Patient was presented with non-ST segment elevation myocardial infarction. Coronary angiography revealed subtotal stenosis of left anterior descending artery at the mid portion. Left circumflex artery lying in usual route and branch out the posterior descending artery. The right coronary artery arisen from terminal circumflex artery. Left anterior descending artery lesion was stented without any complication.

  2. Artery Agenesis: Ipsilateral Common Carotid Artery Hypoplasia

    Directory of Open Access Journals (Sweden)

    Omer Kaya

    2014-01-01

    Full Text Available A 42-year-old female patient, who had been diagnosed with an occlusion of her left internal carotid artery (ICA following Doppler ultrasonographic (US and digitally-subtracted angiographic (DSA examinations performed in an outer healthcare center in order to eliminate the underlying cause of her complaint of amorosis fugax, later applied to our hospital with the same complaint. At Doppler US performed in our hospital’s radiology department, her right common carotid artery (CCA was normal, but her left CCA was hypoplastic. The right internal artery (ICA was validated as normal. At the left side, however, the ICA was apparent only as a stump and it did not demonstrate a continuity. The diagnosis of ICA agenesis was confirmed by the utilization of Doppler US, CT, and DSA imaging, and it was concluded also that ipsilateral CCA hypoplasia could be evaluated as an important clue to the diagnosis of ICA agenesis.

  3. Diagnosis of Intracranial Artery Dissection

    Science.gov (United States)

    KANOTO, Masafumi; HOSOYA, Takaaki

    2016-01-01

    Cerebral arterial dissection is defined as a hematoma in the wall of a cervical or an intracranial artery. Cerebral arterial dissection causes arterial stenosis, occlusion, and aneurysm, resulting in acute infarction and hemorrhage. Image analysis by such methods as conventional angiography, computed tomography, magnetic resonance imaging, and so on plays an important role in diagnosing cerebral arterial dissection. In this study, we explore the methods and findings involved in the diagnosis of cerebral arterial dissection. PMID:27180630

  4. Perceived pitch of complex FM-AM tones--pitch determination process of vibrato sounds.

    Science.gov (United States)

    Iwamiya, S; Miyakura, T; Satoh, N; Hayashi, Y

    1994-09-01

    Pitch-matching experiments were conducted to clarify the pitch determination process of complex FM-AM tones which consist of components whose frequency and amplitude are simultaneously modulated. The pitch is higher when FM and AM of each component are in phase than when they are out of phase. The pitch shift induced by the phase difference between FM and AM of each component becomes larger as its relative power increases. These experimental results suggest that the pitch of complex FM-AM tones is determined as follows: A complex FM-AM tone is resolved into each FM-AM component by the auditory filter bank. The spectral pitch of each FM-AM component is determined by a loudness-weighted pitch averaging processes. The central pattern recognizer determines the pitch of complex FM-AM tones by integration of virtual pitches derived from the spectral pitches. PMID:7872986

  5. L’impact des biocarburants sur l’effet de serre

    Directory of Open Access Journals (Sweden)

    Poitrat Etienne

    2002-09-01

    Full Text Available Selon les statistiques de l’Observatoire de l’Énergie [1], la France a consommé 267 Mtep (tonnes équivalent pétrole d’énergie primaire en 2001, ou 269 Mtep avec correction climatique. Cette consommation comprend 145,6 Mtep sous forme d’énergie fossile (tableau 1. Les émissions corrigées du seul CO2 correspondant à l’énergie primaire consommée ont été entre août 2001 et juillet 2002, de 109 Mt de carbone par an [2]. Les énergies renouvelables (EnR totales utilisées en France sont d’environ 28 Mtep/an, dont 16,1 tep sont produits par les grands barrages hydro-électriques. Les autres EnR sont les bioénergies (11,9 Mtep/an et les énergies restantes, sont la géothermie, le solaire, l’éolien et la petite hydraulique [3]. En Europe, la France occupe la 5e place avec 11,5 % d’énergie renouvelable consommée après la Suède (26,7 %, l’Autriche (23,3 %, la Finlande (20,9 % et le Portugal (16,9 % [4]. D’autre part, la réserve mondiale prouvée des énergies fossiles représente au rythme actuel de consommation, qui est de 77 % de l’énergie totale consommée (tableau 2, environ 45 ans pour le pétrole, 60 ans pour le gaz et 220 à 250 ans pour le charbon. Afin de réduire les émissions de carbone fossile issues de la combustion des 77 % des énergies fossiles utilisées, il est nécessaire de réduire les consommations d’énergie par des économies et l’amélioration des rendements, de développer les énergies renouvelables et les technologies de séquestration du carbone. En France, les transports dépendent à plus de 95 % des hydrocarbures, non renouvelables, dont l’utilisation a une part déterminante (24 % dans l’émission des gaz à effet de serre. Le transport routier représente 81 % de la consommation énergétique du secteur. L’effet de serre se manifeste par un réchauffement de la température de l’air (+ 0,5 °C/100 ans et des océans (+ 0,3 °C/30 ans, avec une augmentation de la

  6. Splanchnic artery aneurysms

    Directory of Open Access Journals (Sweden)

    Davidović Lazar B.

    2006-01-01

    Full Text Available Introduction. Splanchnic artery aneurysms are uncommon but important vascular entity because nearly 25% of all cases present as surgical emergency. Objective. The purpose of our study was to present nine patients operated on at the Institute of cardiovascular diseases, as well as literature review of clinical presentation of the disease. Method. There were three splenic artery aneurysms, two celiac trunk aneurysms, and one aneurysm of the hepatic, superior mesenteric, inferior mesenteric and gastroduodenal artery. All patients were males, mean aged 67.5 years (60-73. In four patients, splanchnic artery aneurysm was discovered accidentally during routine ultrasonographic and angiographic examinations of the abdominal aorta. At that time, arteriovenous fistula was diagnosed in a patient No 1; it was formed after rupture of the splenic artery aneurysm into the splenic vein. Three aneurysms were manifested by abdominal pain and palpable pulsating abdominal mass. Two patients were admitted as urgent cases in the state of hemorrhagic shock and signs of intraabdominal bleeding due to rupture of the splenic and hepatic arteries. In 7 cases, diagnosis was made preoperatively by means of ultrasonography and angiography; in two patients, accurate diagnosis was confirmed during surgery. Results. Proximal and distal ligation of the artery was performed in a patient with rupture of the splenic aneurysm into the splenic vein that caused arteriovenous fistula. Gastroduodenal artery aneurysm was treated by trans-aneurysmatic ligation of its "entering" and "exiting" branches. Aneurysms of distal part of the superior mesenteric and splenic artery were resected without further reconstruction. Partial resection of the aneurysm and endoaneurysmorrhaphy was carried out in one case of celiac trunk aneurysm, and in another, after aneurysm resection, the restoration of blood flow through the hepatic and lienal artery was achieved by Dacron grafts. In a patient with the

  7. Les effets géographiques des éruptions volcaniques

    Directory of Open Access Journals (Sweden)

    Franck Lavigne

    2010-12-01

    Full Text Available Les méthodes de réflexion géographique permettent d’appréhender efficacement les jeux d’échelles et les temporalités multiples des effets induits par les éruptions volcaniques. L’objectif de cette synthèse est ainsi de comprendre les espaces volcaniques en tant qu’objets géographiques, en replaçant les impacts des éruptions au cœur d’une étude spatiale et temporelle. Les impacts de tels événements imposent des recompositions spatiales à l’échelle du volcan lui-même, et, dans le cas d’éruptions de plus grande magnitude, peuvent avoir des conséquences à l’échelle régionale voire mondiale. Les divers exemples abordés ici mettent l’accent sur les risques, la vulnérabilité et la résilience des populations vivant sur ces espaces marqués par les aléas volcaniques.The purpose of this paper aims to study the volcanic areas as geographical objects. Geographical analyses help to understand at different scales the levels of impacts induced by volcanic eruptions. Impacts of such events trigger spatial changes across the volcano itself, and can have consequences at regional or even global level in case of outbreaks of greater magnitude. The various examples discussed here focus on hazards, vulnerability and resilience of people living in those volcanic-hazard prone areas.

  8. L'effet des deformations plastiques severes sur les proprietes d'hydruration du magnesium

    Science.gov (United States)

    Lang, Julien

    Le travail de recherche effectue durant mon projet de maitrise en physique a l'Universite du Quebec a Trois-Rivieres dans les laboratoires de l'Institut de Recherche sur l'Hydrogene etait de comparer l'effet du laminage a froid de la poudre de MgH2 avec celui du broyage mecanique. Nous avons etudie cette nouvelle technique en utilisant un laminoir vertical concu specialement pour laminer de la poudre. Nous avons lamine la poudre de MgH2 5, 25, 50 et 100 fois. La comparaison de la morphologie de la poudre de MgH 2 telle que recu du manufacturier et broye mecaniquement pendant 30 minutes avec celle de la poudre laminee ete faite a l'aide d'un microscope electronique a balayage. Nous avons par la suite mesure les proprietes de sorption d'hydrogene grace un appareil PCT de type Sievert. Nous avons aussi determine la structure cristalline par diffraction de rayons X. A partir de ces resultats, nous avons constate que le nombre optimal de laminages est de cinq et a les caracteristiques d'absorption/desorption d'hydrogene similaires a un broyage mecanique de 30 minutes. Nous avons aussi utilise les courbes de cinetiques d'absorption et de desorption d'hydrogene pour calculer l'etape limitative dans les reactions de sorption des echantillons lamines. Comme cinq laminages se font en environ 10 secondes, on voit que le laminage a froid est une technique plus interessante industriellement que le broyage mecanique a cause de l'important gain en temps et en energie.

  9. Artery by Neuropeptides

    Directory of Open Access Journals (Sweden)

    Esmeralda Sofia Costa Delgado

    2012-01-01

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

  10. [Transposition of Great Artery].

    Science.gov (United States)

    Konuma, Takeshi; Shimpo, Hideto

    2015-07-01

    Transposition of the great artery is one of common congenital cardiac disease resulting cyanosis. Death occurs easily in untreated patients with transposition and intact ventricular septal defect (VSD) in infancy at a few days of age when posterior descending coronary artery (PDA) closed. Since there are 2 parallel circulations, flow from pulmonary to systemic circulation is necessary for systemic oxygenation, and Balloon atrial septostomy or prostaglandin infusion should be performed especially if patient do not have VSD. Although the advent of fetal echocardiography, it is difficult to diagnose the transposition of the great arteries (TGA) as abnormality of great vessels is relatively undistinguishable. The diagnosis of transposition is in itself an indication for surgery, and arterial switch procedure is performed in the case the left ventricle pressure remains more than 2/3 of systemic pressure. Preoperative diagnosis is important as associated anomalies and coronary artery branching patterns are important to decide the operative indication and timing of surgery.

  11. Open Rotor Tone Shielding Methods for System Noise Assessments Using Multiple Databases

    Science.gov (United States)

    Bahr, Christopher J.; Thomas, Russell H.; Lopes, Leonard V.; Burley, Casey L.; Van Zante, Dale E.

    2014-01-01

    Advanced aircraft designs such as the hybrid wing body, in conjunction with open rotor engines, may allow for significant improvements in the environmental impact of aviation. System noise assessments allow for the prediction of the aircraft noise of such designs while they are still in the conceptual phase. Due to significant requirements of computational methods, these predictions still rely on experimental data to account for the interaction of the open rotor tones with the hybrid wing body airframe. Recently, multiple aircraft system noise assessments have been conducted for hybrid wing body designs with open rotor engines. These assessments utilized measured benchmark data from a Propulsion Airframe Aeroacoustic interaction effects test. The measured data demonstrated airframe shielding of open rotor tonal and broadband noise with legacy F7/A7 open rotor blades. Two methods are proposed for improving the use of these data on general open rotor designs in a system noise assessment. The first, direct difference, is a simple octave band subtraction which does not account for tone distribution within the rotor acoustic signal. The second, tone matching, is a higher-fidelity process incorporating additional physical aspects of the problem, where isolated rotor tones are matched by their directivity to determine tone-by-tone shielding. A case study is conducted with the two methods to assess how well each reproduces the measured data and identify the merits of each. Both methods perform similarly for system level results and successfully approach the experimental data for the case study. The tone matching method provides additional tools for assessing the quality of the match to the data set. Additionally, a potential path to improve the tone matching method is provided.

  12. Preliminary Evidence of Preattentive Distinctions of Frequency-Modulated (FM tones that Convey Affect

    Directory of Open Access Journals (Sweden)

    David I Leitman

    2011-10-01

    Full Text Available Recognizing emotion is an evolutionary imperative. An early stage of auditory scene analysis involves the perceptual grouping of acoustic features, which can be based on both temporal coincidence and spectral features such as perceived pitch. Perceived pitch, or fundamental frequency (F0, is an especially salient cue for differentiating affective intent through speech intonation (prosody. We hypothesized that: 1 simple frequency modulated (FM tone abstractions, based on the parameters of actual prosodic stimuli, would be reliably classified as representing differing emotional categories; and 2 that such differences would yield significant mismatch negativities (MMNs - an index of preattentive deviance detection within the auditory environment. We constructed a set of FM tones that approximated the F0 mean and variation of reliably-recognized happy and neutral prosodic stimuli. These stimuli were presented to 13 subjects using a passive listening oddball paradigm. We additionally included stimuli with no frequency modulation (FM and FM tones with identical carrier frequencies but differing modulation depths as control conditions. Following electrophysiological recording, subjects were asked to identify the sounds they heard as happy, sad, angry or neutral. We observed that FM tones abstracted from happy and no expression speech stimuli elicited MMNs. Post-hoc behavioral testing revealed that subjects reliably identified the FM tones in a consistent manner. Finally, we also observed that FM tones and no-FM tones elicited equivalent MMNs. MMNs to FM tones that differentiate affect suggests that these abstractions may be sufficient to characterize prosodic distinctions, and that these distinctions can be represented in pre-attentive auditory sensory memory.

  13. Effects of linguistic and musical experience on Cantonese tone word learning

    OpenAIRE

    Cooper, Angela Kanita

    2010-01-01

    Adult non-native perception is subject to influence from a variety of factors, including linguistic experience as well as other cognitive functions such as musical experience. The present research examines how these two factors influence non-native tone perception and word learning. Native Thai and English listeners, subdivided into musician and non-musician groups, engaged in a perceptual training program. They learned words distinguished by five Cantonese tones during training, also complet...

  14. Stream segregation in the perception of sinusoidally amplitude-modulated tones.

    Science.gov (United States)

    Dolležal, Lena-Vanessa; Beutelmann, Rainer; Klump, Georg M

    2012-01-01

    Amplitude modulation can serve as a cue for segregating streams of sounds from different sources. Here we evaluate stream segregation in humans using ABA- sequences of sinusoidally amplitude modulated (SAM) tones. A and B represent SAM tones with the same carrier frequency (1000, 4000 Hz) and modulation depth (30, 100%). The modulation frequency of the A signals (f(modA)) was 30, 100 or 300 Hz, respectively. The modulation frequency of the B signals was up to four octaves higher (Δf(mod)). Three different ABA- tone patterns varying in tone duration and stimulus onset asynchrony were presented to evaluate the effect of forward suppression. Subjects indicated their 1- or 2-stream percept on a touch screen at the end of each ABA- sequence (presentation time 5 or 15 s). Tone pattern, f(modA), Δf(mod), carrier frequency, modulation depth and presentation time significantly affected the percentage of a 2-stream percept. The human psychophysical results are compared to responses of avian forebrain neurons evoked by different ABA- SAM tone conditions [1] that were broadly overlapping those of the present study. The neurons also showed significant effects of tone pattern and Δf(mod) that were comparable to effects observed in the present psychophysical study. Depending on the carrier frequency, modulation frequency, modulation depth and the width of the auditory filters, SAM tones may provide mainly temporal cues (sidebands fall within the range of the filter), spectral cues (sidebands fall outside the range of the filter) or possibly both. A computational model based on excitation pattern differences was used to predict the 50% threshold of 2-stream responses. In conditions for which the model predicts a considerably larger 50% threshold of 2-stream responses (i.e., larger Δf(mod) at threshold) than was observed, it is unlikely that spectral cues can provide an explanation of stream segregation by SAM. PMID:22984436

  15. Detection of Modulated Tones in Modulated Noise by Non-human Primates

    OpenAIRE

    Bohlen, Peter; Dylla, Margit; Timms, Courtney; Ramachandran, Ramnarayan

    2014-01-01

    In natural environments, many sounds are amplitude-modulated. Amplitude modulation is thought to be a signal that aids auditory object formation. A previous study of the detection of signals in noise found that when tones or noise were amplitude-modulated, the noise was a less effective masker, and detection thresholds for tones in noise were lowered. These results suggest that the detection of modulated signals in modulated noise would be enhanced. This paper describes the results of experim...

  16. Effects of emotional tone and visual complexity on processing health information in prescription drug advertising.

    Science.gov (United States)

    Norris, Rebecca L; Bailey, Rachel L; Bolls, Paul D; Wise, Kevin R

    2012-01-01

    This experiment explored how the emotional tone and visual complexity of direct-to-consumer (DTC) drug advertisements affect the encoding and storage of specific risk and benefit statements about each of the drugs in question. Results are interpreted under the limited capacity model of motivated mediated message processing framework. Findings suggest that DTC drug ads should be pleasantly toned and high in visual complexity in order to maximize encoding and storage of risk and benefit information. PMID:21707406

  17. Etude de la conversion photovoltaïque : effets des résistances parasites des photopiles

    OpenAIRE

    Nguyen, P. H.; Michel, C; Michel, Christine; Bottin, J.

    1983-01-01

    A partir du schéma équivalent électrique habituel nous développons une méthode de calcul du rendement (η) et du facteur de courbe (f) qui tient compte de la résistance série et de la conductance shunt de la photopile. L'effet de ces derniers paramètres est plus drastique sur le rendement que sur le facteur de courbe. Des expressions semi-empiriques en fonction de la résistance réduite et de la conductance réduite sont déduites des calculs de simulation.

  18. Evolution des effets non intentionnels de la lutte chimique contre le campagnol terrestre sur la faune sauvage et domestique

    OpenAIRE

    Coeurdassier, Michael; Berny, Philippe; Couval, Geoffroy; Decors, Anouk; Jacquot, Marion; Queffelec, Stéphane; Quintaine, Thomas; Giraudoux, Patrick

    2014-01-01

    Pendant longtemps, la lutte contre les rongeurs a été exclusivement menée avec des anticoagulants. Depuis 1990, des centaines de cas d'intoxications d'autres animaux (rapaces, renards, sangliers...) par ces substances ont été répertoriés en France. Que sait-on des effets non intentionnels des traitements contre les campagnols sur la faune non-cible ? Comment les évaluer ? Quels dispositifs mettre en place pour prévenir les intoxications ? Les indicateurs disponibles montrent que le passage d'...

  19. Étude de l'effet antibactérien des huiles essentielles de Thymus ciliatus ssp coloratus

    OpenAIRE

    HADDOUCHE, Khalida

    2015-01-01

    Etude de l'effet antibactérien de l'huile essentielle de Thymus ciliatus ssp coloratus Résumé Les plantes médicinales constituent une source immense de métabolites secondaires, dont les huiles essentielles dotées de nombreuses activités biologiques ; souvent recherchées dans le domaine phytopharmaceutique et en agro-alimentaire. Le présent travail porte sur une étude qualitative du pouvoir antibactérien de l'huile essentielle de la plante médicinale: Thymus ciliatus ssp c...

  20. Absolute pitch among students in an American music conservatory: association with tone language fluency.

    Science.gov (United States)

    Deutsch, Diana; Dooley, Kevin; Henthorn, Trevor; Head, Brian

    2009-04-01

    Absolute pitch (AP), the ability to name a musical note in the absence of a reference note, is extremely rare in the U.S. and Europe, and its genesis is unclear. The prevalence of AP was examined among students in an American music conservatory as a function of age of onset of musical training, ethnicity, and fluency in speaking a tone language. Taking those of East Asian ethnicity, the performance level on a test of AP was significantly higher among those who spoke a tone language very fluently compared with those who spoke a tone language fairly fluently and also compared with those who were not fluent in speaking a tone language. The performance level of this last group did not differ significantly from that of Caucasian students who spoke only nontone language. Early onset of musical training was associated with enhanced performance, but this did not interact with the effect of language. Further analyses showed that the results could not be explained by country of early music education. The findings support the hypothesis that the acquisition of AP by tone language speakers involves the same process as occurs in the acquisition of a second tone language.

  1. Absolute pitch among students in an American music conservatory: association with tone language fluency.

    Science.gov (United States)

    Deutsch, Diana; Dooley, Kevin; Henthorn, Trevor; Head, Brian

    2009-04-01

    Absolute pitch (AP), the ability to name a musical note in the absence of a reference note, is extremely rare in the U.S. and Europe, and its genesis is unclear. The prevalence of AP was examined among students in an American music conservatory as a function of age of onset of musical training, ethnicity, and fluency in speaking a tone language. Taking those of East Asian ethnicity, the performance level on a test of AP was significantly higher among those who spoke a tone language very fluently compared with those who spoke a tone language fairly fluently and also compared with those who were not fluent in speaking a tone language. The performance level of this last group did not differ significantly from that of Caucasian students who spoke only nontone language. Early onset of musical training was associated with enhanced performance, but this did not interact with the effect of language. Further analyses showed that the results could not be explained by country of early music education. The findings support the hypothesis that the acquisition of AP by tone language speakers involves the same process as occurs in the acquisition of a second tone language. PMID:19354413

  2. The effects of pitch and duration on the perception of the neutral tone in standard Chinese

    Institute of Scientific and Technical Information of China (English)

    WANG Yunjia

    2005-01-01

    The research aim is to investigate that how pitch and duration affect the perception of the neutral tone in standard Chinese and that which one of the two factors is more important.A psycho-acoustic experiment was conducted, in which the listening stimuli consisted of 15 groups of disyllabic words, and the pitches and durations of the two syllables in each of the words were artificially controlled. Thirty-three standard Chinese native speakers participated in a forced-choice task to judge if the second syllables of the words they heard carried the neutral tone or the normal tones. The results of the experiment indicated that, (1) the effects of both pitch and duration on the perception of the neutral tone are significant; (2) the effect of pitch is larger than that of duration; (3) both the Fo values of the high point in the pitch contour and the pitch contour pattern have influence on the perception. The results of the experiment were correspondent to some extent to those of the previous acoustic analyses on the neutral tone.The diversity between the results of the presented perceptual study and those of the acoustical studies implies that the acoustic features of the neutral tone that exist in natural speech while do not affect the perception may be phonologically redundant.

  3. Hardware Implementation of an Automatic Rendering Tone Mapping Algorithm for a Wide Dynamic Range Display

    Directory of Open Access Journals (Sweden)

    Orly Yadid-Pecht

    2013-10-01

    Full Text Available Tone mapping algorithms are used to adapt captured wide dynamic range (WDR scenes to the limited dynamic range of available display devices. Although there are several tone mapping algorithms available, most of them require manual tuning of their rendering parameters. In addition, the high complexities of some of these algorithms make it difficult to implement efficient real-time hardware systems. In this work, a real-time hardware implementation of an exponent-based tone mapping algorithm is presented. The algorithm performs a mixture of both global and local compression on colored WDR images. An automatic parameter selector has been proposed for the tone mapping algorithm in order to achieve good tone-mapped images without manual reconfiguration of the algorithm for each WDR image. Both algorithms are described in Verilog and synthesized for a field programmable gate array (FPGA. The hardware architecture employs a combination of parallelism and system pipelining, so as to achieve a high performance in power consumption, hardware resources usage and processing speed. Results show that the hardware architecture produces images of good visual quality that can be compared to software-based tone mapping algorithms. High peak signal-to-noise ratio (PSNR and structural similarity (SSIM scores were obtained when the results were compared with output images obtained from software simulations using MATLAB.

  4. Use of paravascular admittance waveforms to monitor relative change in arterial blood pressure

    Science.gov (United States)

    Zielinski, Todd M.; Hettrick, Doug; Cho, Yong

    2010-04-01

    Non-invasive methods to monitor ambulatory blood pressure often have limitations that can affect measurement accuracy and patient adherence [1]. Minimally invasive measurement of a relative blood pressure surrogate with an implantable device may provide a useful chronic diagnostic and monitoring tool. We assessed a technique that uses electrocardiogram and paravascular admittance waveform morphology analysis to one, measure a time duration (vascular tone index, VTI in milliseconds) change from the electrocardiogram R-wave to admittance waveform peak and two, measure the admittance waveform minimum, maximum and magnitude as indicators of change in arterial compliance/distensibility or pulse pressure secondary to change in afterload. Methods: Five anesthetized domestic pigs (32 ± 4.2 kg) were used to study the effects of phenylephrine (1-5 ug/kg/min) on femoral artery pressure and admittance waveform morphology measured with a quadrapolar electrode array catheter placed next to the femoral artery to assess the relative change in arterial compliance due to change in peripheral vascular tone. Results: Statistical difference was observed (p blood pressure may be suitable for implantable devices to detect progression of cardiovascular disease such as hypertension.

  5. Les effets musculaires de la vitamine D : application à la perte musculaire liée à l’âge

    OpenAIRE

    Walrand Stéphane

    2014-01-01

    Au-delà de ses rôles biologiques classiques sur la santé osseuse, les effets extra-squelettiques de la vitamine D font actuellement l’objet de nombreuses recherches. La présence du récepteur de la vitamine D dans la plupart des tissus de l’organisme vient d’ailleurs renforcer l’argument en faveur de ses fonctions multiples. Parmi celles-ci, l’effet de la vitamine D sur la masse et les performances musculaires a été longtemps pre...

  6. Effets de l'apport de bois raméal sur la plante et le sol : une revue des résultats expérimentaux

    OpenAIRE

    Barthès, Bernard; Manlay, R.; Porte, O.

    2010-01-01

    L_amendement du sol avec des branches, notamment avec des bois raméaux fragmentés (BRF), suscite un intérêt croissant chez les agriculteurs et les services de vulgarisation, mais la validation scientifique de cette pratique est incomplète. Cet article synthétise les résultats statistiquement significatifs concernant l_effet d_apports enfouis ou paillés (mulch) de BRF sur les cultures et le sol, en milieu tempéré et tropical. L_apport de BRF a généralement un effet positif sur le rendeme...

  7. Piezo1 in Smooth Muscle Cells Is Involved in Hypertension-Dependent Arterial Remodeling

    Directory of Open Access Journals (Sweden)

    Kevin Retailleau

    2015-11-01

    Full Text Available The mechanically activated non-selective cation channel Piezo1 is a determinant of vascular architecture during early development. Piezo1-deficient embryos die at midgestation with disorganized blood vessels. However, the role of stretch-activated ion channels (SACs in arterial smooth muscle cells in the adult remains unknown. Here, we show that Piezo1 is highly expressed in myocytes of small-diameter arteries and that smooth-muscle-specific Piezo1 deletion fully impairs SAC activity. While Piezo1 is dispensable for the arterial myogenic tone, it is involved in the structural remodeling of small arteries. Increased Piezo1 opening has a trophic effect on resistance arteries, influencing both diameter and wall thickness in hypertension. Piezo1 mediates a rise in cytosolic calcium and stimulates activity of transglutaminases, cross-linking enzymes required for the remodeling of small arteries. In conclusion, we have established the connection between an early mechanosensitive process, involving Piezo1 in smooth muscle cells, and a clinically relevant arterial remodeling.

  8. Peripheral Arterial Tonometry to Measure the Effects of Vardenafil on Sympathetic Tone in Men with Lifelong Premature Ejaculation

    Directory of Open Access Journals (Sweden)

    Davide Francomano

    2013-01-01

    vardenafil (0.6 ± 0.3 versus 4.5 ± 1.1 min, when compared with placebo. STAI-X1 and STAI-X2 scores fell within the normal range after treatment with vardenafil (. Vardenafil was an effective treatment in men with LL-PE; improvements of IELT may be due to increased NO production which is able to reduce adrenergic overactivity and anxiety levels.

  9. Coronary Artery Bypass

    Directory of Open Access Journals (Sweden)

    Kadri Ceberut

    2011-01-01

    Full Text Available Ancient schwannoma is a rare variant of neural tumors though rarely seen in the thorax. The combination with coronary artery diseases is also rare. Here we describe a 66 year-old male who had undergone one-stage combined surgery for thoracic ancient schwannomas removal and coronary artery disease. The masses were, respectively, 13 cm in the middle mediastinum and 5 cm in diameter originating from the intercostal nerve. The tumors were successfully removed using sternotomy, and then a coronary artery bypass grafting was performed. Here we discuss this rare tumor in relation to the relevant literature.

  10. KCNA5 gene is not confirmed as a systemic sclerosis-related pulmonary arterial hypertension genetic susceptibility factor

    OpenAIRE

    Bossini-Castillo, L.; Simeón, Carmen P.; Beretta, L; Broen, Jasper C.; Vonk, Madelon C; Callejas-Rubio, J. L.; Carreira, P; Rodríguez-Rodríguez, Luis; García-Portales, Rosa; González-Gay, M. A.; Castellví, I.; Camps, M T; Tolosa, Carlos; Vicente-Rabaneda, Esther; Egurbide, M V

    2012-01-01

    Introduction: Potassium voltage-gated channel shaker-related subfamily member 5 (KCNA5) is implicated in vascular tone regulation, and its inhibition during hypoxia produces pulmonary vasoconstriction. Recently, a protective association of the KCNA5 locus with systemic sclerosis (SSc) patients with pulmonary arterial hypertension (PAH) was reported. Hence, the aim of this study was to replicate these findings in an independent multicenter Caucasian SSc cohort. Methods: The 2,343 SSc cases...

  11. Analysis of audio-vestibular assessment in acute low-tone hearing loss.

    Science.gov (United States)

    Im, Gi Jung; Kim, Sung Kyun; Choi, June; Song, Jae Jun; Chae, Sung Won; Jung, Hak Hyun

    2016-07-01

    Conclusion This study demonstrated excellent hearing recovery following the combined treatment of diuretic and oral steroid, and electrocochleography (ECoG) was significantly higher than normal side. This study reports characteristics of acute low-tone hearing loss (ALHL) that show the greater low-tone hearing loss, the higher ECoG, and excellent recovery, even-though low-tone hearing loss is worse, which can be different compared with sudden deafness. Objective To analyze ALHL without vertigo, this study compared the ALHL group with all patients exhibiting low-tone hearing loss and ear fullness. Hearing changes and vestibular functions were analyzed. Materials and methods ALHL was defined as a mean hearing loss of ≥ 30 dB at 125, 250, and 500 Hz, and ≤ 20 dB at 2, 4, and 8 kHz. From 156 cases of low-tone hearing loss of more than 10 dB without vertigo, 31 met the ALHL criteria and were subjected to audio-vestibular assessments including PTA, ECoG, vestibular evoked myogenic potential (VEMP) testing, and caloric testing. Results In ALHL, low-tone hearing loss was 42.7 ± 9.5 dB, and 83.9% of ALHL significantly recovered by more than 10 dB. The ECoG in ALHL was 0.334 ± 0.11 (higher than 0.25 ± 0.08 on the normal side) and ECoG abnormality was 35.5% (the greater low-tone hearing loss, the higher ECoG value). PMID:26963446

  12. The interaction of tone with voicing and foot structure: evidence from Kera phonetics and phonology

    Science.gov (United States)

    Pearce, Mary Dorothy

    This thesis uses acoustic measurements as a basis for the phonological analysis of the interaction of tone with voicing and foot structure in Kera (a Chadic language). In both tone spreading and vowel harmony, the iambic foot acts as a domain for spreading. Further evidence for the foot comes from measurements of duration, intensity and vowel quality. Kera is unusual in combining a tone system with a partially independent metrical system based on iambs. In words containing more than one foot, the foot is the tone bearing unit (TBU), but in shorter words, the TBU is the syllable. In perception and production experiments, results show that Kera speakers, unlike English and French, use the fundamental frequency as the principle cue to 'Voicing" contrast. Voice onset time (VOT) has only a minor role. Historically, tones probably developed from voicing through a process of tonogenesis, but synchronically, the feature voice is no longer contrastive and VOT is used in an enhancing role. Some linguists have claimed that Kera is a key example for their controversial theory of long-distance voicing spread. But as voice is not part of Kera phonology, this thesis gives counter-evidence to the voice spreading claim. An important finding from the experiments is that the phonological grammars are different between village women, men moving to town and town men. These differences are attributed to French contact. The interaction between Kera tone and voicing and contact with French have produced changes from a 2-way voicing contrast, through a 3-way tonal contrast, to a 2-way voicing contrast plus another contrast with short VOT. These diachronic and synchronic tone/voicing facts are analysed using laryngeal features and Optimality Theory. This thesis provides a body of new data, detailed acoustic measurements, and an analysis incorporating current theoretical issues in phonology, which make it of interest to Africanists and theoreticians alike.

  13. Resting heart rate, vagal tone, and reactive and proactive aggression in Chinese children.

    Science.gov (United States)

    Xu, Yiyuan; Raine, Adrian; Yu, Lidong; Krieg, Alexander

    2014-01-01

    Abundant research conducted in Western contexts has shown that biological risk factors such as low resting heart rate (HR) might be related to childhood aggression. However, it was unclear (1) how resting HR, as well as other markers of cardiac functions such as resting vagal tone, may be related to subtypes of aggression such as reactive and proactive aggression, and (2) whether the HR-aggression relation can be replicated in non-Western contexts. Therefore, this study examined the concurrent and prospective relations between resting HR, vagal tone, and Chinese children's reactive and proactive aggression. Participants were 183 children (M age=7.64 years, 91 girls) recruited from an elementary school in Zhenjiang, PRC. Children's resting HR and vagal tone were assessed in the second grade (T1). Teachers rated children's reactive and proactive aggression in the second (T1) and fourth grade (T2). Results showed that lower resting HR at T1 was associated with higher reactive and proactive aggression at T1 and T2, and higher vagal tone was associated with lower HR, which in turn was related to higher reactive and proactive aggression at T1 and T2. Lower vagal tone was directly related to higher reactive but not proactive aggression at T1 and T2, whereas lower HR was related to higher reactive aggression at T2 for children with low or moderate vagal tone but was not for children with high vagal tone. These psychophysiological findings from a non-Western context add additional support for both similarities and differences between reactive and proactive aggression in childhood.

  14. Brain Plasticity in Speech Training in Native English Speakers Learning Mandarin Tones

    Science.gov (United States)

    Heinzen, Christina Carolyn

    The current study employed behavioral and event-related potential (ERP) measures to investigate brain plasticity associated with second-language (L2) phonetic learning based on an adaptive computer training program. The program utilized the acoustic characteristics of Infant-Directed Speech (IDS) to train monolingual American English-speaking listeners to perceive Mandarin lexical tones. Behavioral identification and discrimination tasks were conducted using naturally recorded speech, carefully controlled synthetic speech, and non-speech control stimuli. The ERP experiments were conducted with selected synthetic speech stimuli in a passive listening oddball paradigm. Identical pre- and post- tests were administered on nine adult listeners, who completed two-to-three hours of perceptual training. The perceptual training sessions used pair-wise lexical tone identification, and progressed through seven levels of difficulty for each tone pair. The levels of difficulty included progression in speaker variability from one to four speakers and progression through four levels of acoustic exaggeration of duration, pitch range, and pitch contour. Behavioral results for the natural speech stimuli revealed significant training-induced improvement in identification of Tones 1, 3, and 4. Improvements in identification of Tone 4 generalized to novel stimuli as well. Additionally, comparison between discrimination of across-category and within-category stimulus pairs taken from a synthetic continuum revealed a training-induced shift toward more native-like categorical perception of the Mandarin lexical tones. Analysis of the Mismatch Negativity (MMN) responses in the ERP data revealed increased amplitude and decreased latency for pre-attentive processing of across-category discrimination as a result of training. There were also laterality changes in the MMN responses to the non-speech control stimuli, which could reflect reallocation of brain resources in processing pitch patterns

  15. The effect of taurine on high potassium-and noradrenaline-induced contraction in rabbit ear artery.

    OpenAIRE

    Franconi, F.; Giotti, A.; Manzini, S.; Martini, F.; Stendardi, I.; Zilletti, L.

    1982-01-01

    1 Intraluminal administration of taurine (40 mM) did not affect the contractile tone of rabbit isolated ear artery 2 Taurine (10-80 mM) exerted a powerful concentration-dependent, vasodilator action in arteries contracted with high potassium medium. 3 In the same experimental conditions, the taurine analogues beta-alanine and homotaurine, had no effect. 4 Taurine (40-80 mM) did not affect in a significant manner the tonic component of the noradrenaline (5x10(-6 M)-induced contraction. 5 When ...

  16. Coronary artery spasm

    Science.gov (United States)

    ... blocker or a long-acting nitrate long-term. Beta-blockers are another type of medicine that is used with other coronary artery problems. However, beta-blockers may make this problem worse. They should be ...

  17. Peripheral Arterial Disease

    Science.gov (United States)

    Peripheral arterial disease (PAD) happens when there is a narrowing of the blood vessels outside of your heart. The cause of ... smoking. Other risk factors include older age and diseases like diabetes, high blood cholesterol, high blood pressure, ...

  18. Pulmonary Arterial Hypertension

    Science.gov (United States)

    Pulmonary Arterial Hypertension What Is Pulmonary Hypertension? To understand pulmonary hypertension (PH) it helps to understand how blood ows throughout your body. While the heart is one organ, it ...

  19. Renal arteries (image)

    Science.gov (United States)

    A renal angiogram is a test used to examine the blood vessels of the kidneys. The test is performed ... main vessel of the pelvis, up to the renal artery that leads into the kidney. Contrast medium ...

  20. Coronary Artery Bypass Surgery

    Science.gov (United States)

    ... don't help, you may need coronary artery bypass surgery. The surgery creates a new path for ... narrowed area or blockage. This allows blood to bypass (get around) the blockage. Sometimes people need more ...

  1. Effect of beta-adrenergic blockade on elevated arterial compliance and low systemic vascular resistance in cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Bendtsen, F; Henriksen, Jens Henrik Sahl

    2001-01-01

    beta-blockers, but the effect of this treatment on arterial compliance has not been investigated. The aim of the present study was therefore to assess the effects of propranolol on the arterial compliance of patients with cirrhosis. METHODS: Twenty patients with cirrhosis underwent a haemodynamic......) of 17.8 mmHg, and responded to beta-blocker treatment with a significant reduction in the HVPG (-16%; P < 0.001). Arterial compliance was elevated (1.27 versus controls 1.01 ml/mmHg; P < 0.001), but remained almost unchanged during beta-adrenergic blockade (1.27 versus 1.29 ml/mmHg, +2%, ns), whereas...... beta-blockers increases small vessel (arteriolar) vascular tone towards the normal level, but does not affect the elevated compliance of the larger arteries in patients with cirrhosis....

  2. Effects of thrombin, PAR-1 activating peptide and a PAR-1 antagonist on umbilical artery resistance in vitro

    Directory of Open Access Journals (Sweden)

    Elliott John T

    2005-02-01

    Full Text Available Abstract Background The non-thrombotic effects of thrombin in cardiovascular tissues, as mediated via the protease activated receptors (PARs, and particularly PAR-1, have been the focus of much recent research. The aims of this study were to evaluate the effects of thrombin, a specific PAR-1 activating peptide (PAR1-AP, and a PAR-1 antagonist on human umbilical artery tone in vitro. Methods Human umbilical artery samples were obtained from 17 women at term. Arterial rings were suspended under physiologic conditions for isometric recording. The in vitro effects of thrombin (0.5 units/mL to 3 units/mL, PAR1-AP TFLLR-NH2 [10(-9 to 10(-6 M], and PAR-1 antagonist (N-trans cinnamoyl- p-fluoroPhe-p-guanidinoPhe-Leu-Arg-Orn-NH2 [10(-9 M to 10(-5 M] on umbilical artery tone were measured. Results Both thrombin and TFLLR-NH2 exerted a potent cumulative vasodilatory effect on human umbilical artery resistance (P 0.05. Conclusion These findings highlight a potential role for thrombin and PAR-1 receptors in vascular regulation of feto-placental blood flow in normal pregnancy, and in association with the vascular lesions associated with IUGR and pre-eclampsia.

  3. Copper Induces Vasorelaxation and Antagonizes Noradrenaline -Induced Vasoconstriction in Rat Mesenteric Artery

    Directory of Open Access Journals (Sweden)

    Yu-Chun Wang

    2013-11-01

    Full Text Available Background/Aims: Copper is an essential trace element for normal cellular function and contributes to critical physiological or pathological processes. The aim of the study was to investigate the effects of copper on vascular tone of rat mesenteric artery and compare the effects of copper on noradrenaline (NA and high K+ induced vasoconstriction. Methods: The rat mesenteric arteries were isolated and the vessel tone was measured by using multi wire myograph system in vitro. Blood pressure of carotid artery in rabbits was measured by using physiological data acquisition and analysis system in vivo. Results: Copper dose-dependently blunted NA-induced vasoconstriction of rat mesenteric artery. Copper-induced vasorelaxation was inhibited when the vessels were pretreated with NG-nitro-L-arginine methyl ester (L-NAME. Copper did not blunt high K+-induced vasoconstriction. Copper preincubation inhibited NA-evoked vasoconstriction and the inhibition was not affected by the presence of L-NAME. Copper preincubation showed no effect on high K+-evoked vasoconstriction. Copper chelator diethyldithiocarbamate trihydrate (DTC antagonized the vasoactivity induced by copper in rat mesenteric artery. In vivo experiments showed that copper injection (iv significantly decreased blood pressure of rabbits and NA or DTC injection (iv did not rescue the copper-induced hypotension and animal death. Conclusion: Copper blunted NA but not high K+-induced vasoconstriction of rat mesenteric artery. The acute effect of copper on NA-induced vasoconstriction was depended on nitric oxide (NO, but the effect of copper pretreatment on NA-induced vasoconstriction was independed on NO, suggesting that copper affected NA-induced vasoconstriction by two distinct mechanisms.

  4. Relationships among choral tone and intensity and the spectra of bass singing voices

    Science.gov (United States)

    Neufeld, Charles Warren

    The purpose of this spectrographic study was to compare mean formant frequencies (F1, F2, F3, F4 , F5) of three vowels---[a], [o], and [i]---as bass singers (N = 36) performed identical musical phrases in an authentic choral music performance environment. Two types of choral tone, a "blended" sound with minimal vibrato and an opera-chorus-like sound with free vibrato, and two levels of intensity, piano and forte, were employed in a fully crossed 2 x 2 x 3 multiple analysis of variance (MANOVA) design. A panel of experts verified the tone type and intensity in the subject trials. MANOVA results revealed significant differences among formant frequencies for the main effects of vowel, intensity, and tone type, and interaction effects for vowel by intensity and intensity by tone type. Numerous significant differences were found among the five formant univariate effects. Contrast analysis led to the retention of the null hypothesis (H0) of no significant difference between tone types in F1, and the rejection of H 0 for F2, F3, F4, and F5. The H0 of no significant difference between intensifies was retained for F3, and rejected for all other formants. H0 was rejected for all formants except F5 for the main effect vowel. The null hypotheses for the three two-way interactions were rejected for all formants except vowel by intensity in F3. H0 was rejected for each of the five formants for the interaction of vowel by intensity by tone type. The influence of tone type was eliminated as a factor in F1. F2 was influenced mostly by vowel. Intensity was subordinate to tone type and vowel in F3. F4, the most unstable of all the formants, was subject to differences throughout all the combined effects. Vowel had little or no effect on F5 in all combined effect analyses. Contrast analyses resulted in numerous other findings. The study outcomes affirm the influence of tongue and mouth shape on vowel stability measured in F1 and F2. Results further indicate that aurally identifiable

  5. Annoyance due to discrete tones in broadband background noise. Part 2: Analysis

    Science.gov (United States)

    Robinson, D. W.

    1992-04-01

    A series of subjective tests of annoyance of tonal noises was described in a companion report (Robinson and Wright, 1991). Each stimulus consisted of a pure tone superimposed on a broadband noise. The present report analyses the results and derives from them a general algebraic formula accommodating all the variables (frequency and sensation level of the tonal component, level and spectrum shape of the broadband component). Annoyance of each tone/noise combination was determined as an overall tone penalty, that is, the equivalent increment in decibels of the broadband component alone which was required to match the annoyance of the combination. These increments varied with the parameters of the stimuli in a complicated manner. Heuristic means revealed and underlying pattern of comparative simplicity: the overall tone penalty consists of the sum of two terms. The first term is a constant sub-multiple of the A-weighted level increase caused by adding the tonal component to the broadband noise and appears to be related to the corresponding increase of loudness level in phons. The second term is a multiple product of non-interactive factors expressing the dependence on the four parameters of the signal. The tone-frequency factor is given as a polynomial in log frequency. Sensation level appears directly in the formula as a proportionality factor; its magnitude has to be derived from the difference between the sound pressure level of the tone and that of the 1/3-octave band of the broadband component embracing the tone frequency, together with a detection ratio in decibels which is given as a quadratic function of frequency. The factor for broadband noise level is a negative exponential of level, falling by 22 percent for each 10 dB(A) increase in level. Finally, spectrum shape is accommodated by an empirical function which is linear in the difference between the C and A weighted sound pressure levels of the broadband noise. The algebraic formula reproduces the

  6. Effects of linguistic experience on early levels of perceptual tone processing

    Science.gov (United States)

    Huang, Tsan; Johnson, Keith

    2005-04-01

    This study investigated the phenomenon of language-specificity in Mandarin Chinese tone perception. The main question was whether linguistic experience affects the earliest levels of perceptual processing of tones. Chinese and American English listeners participated in four perception experiments, which involved short inter-stimulus intervals (300 ms or 100 ms) and an AX discrimination or AX degree-of-difference rating task. Three experiments used natural speech monosyllabic tone stimuli and one experiment used time-varying sinusoidal simulations of Mandarin tones. AE listeners showed psychoacoustic listening in all experiments, paying much attention to onset and offset pitch. Chinese listeners showed language-specific patterns in all experiments to various degrees, where tonal neutralization rules reduced perceptual distance between two otherwise contrastive tones for Chinese listeners. Since these experiments employed procedures hypothesized to tap the auditory trace mode (Pisoni, Percept. Psychophys. 13, 253-260 (1973)], language-specificity found in this study seems to support the proposal of an auditory cortical map [Guenther et al., J. Acoust. Soc. Am. 23, 213-221 (1999)]. But the model needs refining to account for different degrees of language-specificity, which are better handled by Johnsons (2004, TLS03:26-41) lexical distance model, although the latter model is too rigid in assuming that linguistic experience does not affect low-level perceptual tasks such as AX discrimination with short ISIs.

  7. Relative importance of temporal envelope and fine structure in lexical-tone perception (L)

    Science.gov (United States)

    Xu, Li; Pfingst, Bryan E.

    2003-12-01

    The relative importance of temporal envelope and fine structure in speech and music perception was investigated by Smith et al. [Nature (London) 416, 87-90 (2002)] using ``auditory chimera'' in which the envelope from one sound was paired with the fine structure of another. Smith et al. found that, when 4 to 16 frequency bands were used, recognition of English speech was dominated by the envelope, whereas recognition of melody was dominated by the fine structure. In the present study, Mandarin Chinese monosyllables were divided into 4, 8, or 16 frequency bands and the fine structure and envelope of one tone pattern were exchanged with those of another tone pattern of the same monosyllable. Five normal-hearing native Mandarin Chinese speakers completed a four-alternative forced-choice tone-identification task. In the vast majority of trials, subjects based their identification of the monosyllables on the fine structure rather than the envelope. Thus, the relative importance of envelope and fine structure for lexical-tone perception resembled that for melody recognition rather than that for English speech recognition. Delivering fine-structure information in cochlear implant stimulation could be particularly beneficial for lexical-tone perception.

  8. What the [bleep]? Enhanced absolute pitch memory for a 1000Hz sine tone.

    Science.gov (United States)

    Van Hedger, Stephen C; Heald, Shannon L M; Nusbaum, Howard C

    2016-09-01

    Many individuals are able to perceive when the tuning of familiar stimuli, such as popular music recordings, has been altered. This suggests a kind of ubiquitous pitch memory, though it is unclear how this ability differs across individuals with and without absolute pitch (AP) and whether it plays any role in AP. In the present study, we take advantage of a salient single frequency - the 1000Hz sine tone used to censor taboo words in broadcast media - to assess the nature of this kind of pitch memory across individuals with and without AP. We show that non-AP participants are accurate at selecting the correct version of the censor tone among incorrect versions shifted by either one or two semitones, though their accuracy was still below that of an AP population (Experiment 1). This suggests a benefit for AP listeners that could be due to the use of explicit note categories or greater amounts of musical training. However, AP possessors still outperformed all non-AP participants when incorrect versions of the censor tone were shifted within a note category, even when controlling for musical experience (Experiment 2). Experiment 3 demonstrated that AP listeners did not appear to possess a category label for the censor tone that could have helped them differentiate the censor tones used in Experiment 2. Overall, these results suggest that AP possessors may have better pitch memory, even when divorced from pitch labeling (note categories). As such, these results have implications for how AP may develop and be maintained. PMID:27289485

  9. Durations required to distinguish noise and tone: Effects of noise bandwidth and frequency.

    Science.gov (United States)

    Taghipour, Armin; Moore, Brian C J; Edler, Bernd

    2016-05-01

    Perceptual audio coders exploit the masking properties of the human auditory system to reduce the bit rate in audio recording and transmission systems; it is intended that the quantization noise is just masked by the audio signal. The effectiveness of the audio signal as a masker depends on whether it is tone-like or noise-like. The determination of this, both physically and perceptually, depends on the duration of the stimuli. To gather information that might improve the efficiency of perceptual coders, the duration required to distinguish between a narrowband noise and a tone was measured as a function of center frequency and noise bandwidth. In experiment 1, duration thresholds were measured for isolated noise and tone bursts. In experiment 2, duration thresholds were measured for tone and noise segments embedded within longer tone pulses. In both experiments, center frequencies were 345, 754, 1456, and 2658 Hz and bandwidths were 0.25, 0.5, and 1 times the equivalent rectangular bandwidth of the auditory filter at each center frequency. The duration thresholds decreased with increasing bandwidth and with increasing center frequency up to 1456 Hz. It is argued that the duration thresholds depended mainly on the detection of amplitude fluctuations in the noise bursts. PMID:27250144

  10. Modeling tone and intonation in Mandarin and English as a process of target approximation.

    Science.gov (United States)

    Prom-on, Santitham; Xu, Yi; Thipakorn, Bundit

    2009-01-01

    This paper reports the development of a quantitative target approximation (qTA) model for generating F(0) contours of speech. The qTA model simulates the production of tone and intonation as a process of syllable-synchronized sequential target approximation [Xu, Y. (2005). "Speech melody as articulatorily implemented communicative functions," Speech Commun. 46, 220-251]. It adopts a set of biomechanical and linguistic assumptions about the mechanisms of speech production. The communicative functions directly modeled are lexical tone in Mandarin and lexical stress in English and focus in both languages. The qTA model is evaluated by extracting function-specific model parameters from natural speech via supervised learning (automatic analysis by synthesis) and comparing the F(0) contours generated with the extracted parameters to those of natural utterances through numerical evaluation and perceptual testing. The F(0) contours generated by the qTA model with the learned parameters were very close to the natural contours in terms of root mean square error, rate of human identification of tone, and focus and judgment of naturalness by human listeners. The results demonstrate that the qTA model is both an effective tool for research on tone and intonation and a potentially effective system for automatic synthesis of tone and intonation.

  11. The effects of tones in noise on human annoyance and performance

    Science.gov (United States)

    Lee, Joonhee

    Building mechanical equipment often generates prominent tones because most systems include rotating parts like fans and pumps. These tonal noises can cause unpleasant user experiences in spaces and, in turn, lead to increased complaints by building occupants. Currently, architectural engineers can apply the noise criteria guidelines in standards or publications to achieve acceptable noise conditions for assorted types of spaces. However, these criteria do not apply well if the noise contains perceptible tones. The annoyance thresholds experienced by the general population with regards to the degree of tones in noise is a significant piece of knowledge that has not been well-established. Thus, this dissertation addresses the relationship between human perception and noises with tones in the built environment. Four phases of subjective testing were conducted in an indoor acoustic testing chamber at the University of Nebraska to achieve the research objective. The results indicate that even the least prominent tones in noises can significantly decrease the cognitive performance of participants on a mentally demanding task. Factorial repeated-measures analysis of variance of test results have proven that tonality has a crucial influence on working memory capacity of subjects, whereas loudness levels alone did not. A multidimensional annoyance model, incorporating psycho-acoustical attributes of noise in addition to loudness and tonality, has been proposed as a more accurate annoyance model.

  12. Perceptual and instrumental assessments of orofacial muscle tone in dysarthric and normal speakers

    Directory of Open Access Journals (Sweden)

    Angela M. Dietsch, PhD

    2014-11-01

    Full Text Available Clinical assessment of orofacial muscle tone is of interest for differential diagnosis of the dysarthrias, but standardized procedures and normative data are lacking. In this study, perceptual ratings of tone were compared with instrumental measures of tissue stiffness for facial, lingual, and masticatory muscles in 70 individuals with dysarthria. Perceptual and instrumental tone data were discordant and failed to discriminate between five dysarthria types. These results raised concerns about the validity of Myoton-3 stiffness measures in the orofacial muscles. Therefore, a second study evaluated contracted and relaxed orofacial muscles in 10 neurotypical adults. Results for the cheek, masseter, and lateral tongue surface followed predictions, with significantly higher tissue stiffness during contraction. In contradiction, stiffness measures from the superior surface of the tongue were lower during contraction. Superior-to-inferior tongue thickness was notably increased during contraction. A third study revealed that tissue thickness up to ~10 mm significantly affected Myoton-3 measures. Altered tissue thickness due to neuromuscular conditions like spasticity and atrophy may have undermined the detection of group differences in the original sample of dysarthric speakers. These experiments underscore the challenges of assessing orofacial muscle tone and identify considerations for quantification of tone-related differences across dysarthria groups in future studies.

  13. Coronary anomaly: the single coronary artery

    Institute of Scientific and Technical Information of China (English)

    QIN Xu-guang; XIONG Wei-guo; LU Chun-peng; GONG Cheng-jie; SHANG Li-hua

    2010-01-01

    @@ Single coronary artery (SCA), defined as an artery that arises from the arterial trunk and nourishes the entire myocardium, is rare. We report two cases of SCA, one is the right coronary artery (RCA) originating from the middle of left descending artery (LAD), and the other is the left main coronary artery (LMCA) arising from the proximal right coronary artery.

  14. Ouabain-induced increases in resting tone of human hyperplastic prostate following repeated noradrenaline and electrical field stimulation.

    OpenAIRE

    Guh, J. H.; Ko, F. N.; Chueh, S. C.; Lai, M.K.; Teng, C. M.

    1996-01-01

    1. The effect of ouabain on contractions to repeated noradrenaline stimulation and electrical field stimulation of human hyperplastic prostate was examined. Ouabain (1 microM) did not induce contractile response per se but progressively increased the resting tone (i.e., the tone between one noradrenaline stimulation, or electrical field stimulation, and the following) of human hyperplastic prostate. 2. The increased tone by ouabain following repeated noradrenaline stimulations or electrical f...

  15. Patterned Tone Sequences Reveal Non-Linear Interactions in Auditory Spectrotemporal Receptive Fields in the Inferior Colliculus

    OpenAIRE

    BRIMIJOIN, W. OWEN; O'Neill, William E.

    2010-01-01

    Linear measures of auditory receptive fields do not always fully account for a neuron's response to spectrotemporally-complex signals such as frequency-modulated sweeps (FM) and communication sounds. A possible source of this discrepancy is cross-frequency interactions, common response properties which may be missed by linear receptive fields but captured using two-tone masking. Using a patterned tonal sequence that included a balanced set of all possible tone-to-tone transitions, we have her...

  16. Etude des effets singuliers produits par les particules énergétiques chargées de l’environnement radiatif spatial sur les capteurs d’images CMOS

    OpenAIRE

    Lalucaa, Valérian

    2013-01-01

    Ce mémoire de thèse traite des effets singuliers produits par les milieux radiatifs sur les capteurs d’images CMOS. Le travail se concentre sur les effets provoqués par les ions lourds sur les capteurs utilisant des pixels 3T à photodiode standard et des pixels 4T et 5T à photodiodes pincées. Dans un premier temps, l’étude se concentre sur l’environnement spatial et l’architecture des capteurs. La comparaison avec la littérature met en évidence les effets les plus critiques sur les capteurs :...

  17. The effect of L1 prosodic backgrounds of Cantonese and Japanese speakers on the perception of Mandarin tones after training

    Science.gov (United States)

    So, Connie K.

    2005-04-01

    The present study investigated to what extent ones' L1 prosodic backgrounds affect their learning of a new tonal system. The question as to whether native speakers of a tone language perform differently from those of a pitch accent language will be addressed. Twenty native speakers of Hong Kong Cantonese (a tone language) and Japanese (a pitch accent language) were assigned to two groups. All of them had had no prior knowledge of Mandarin, and had never received any form of musical training before they participated in the study. Their performance of the identification of Mandarin tones before and after a short-term training was compared. Analysis of listeners' tonal confusions in the pretest, posttest, and generalization tests revealed that both Cantonese and Japanese listeners had more confusion for two contrastive tone pairs: Tone 1-Tone 4, and Tone 2-Tone 3. Moreover, Cantonese speakers consistently had greater difficulty than Japanese speakers in distinguishing the tones in each pair. These imply that listeners L1 prosodic backgrounds are at work during the process of learning a new tonal system. The findings will be further discussed in terms of the Perceptual Assimilation Model (Best, 1995). [Work supported by SSHRC.

  18. Nocturnal foot blood flow in patients with arterial insufficiency

    DEFF Research Database (Denmark)

    Jelnes, Rolf; Tønnesen, K H

    1984-01-01

    Twenty-four hour continuous recording of xenon (133Xe) wash-out from the forefoot was performed on patients with normal circulations (n = 10) and on patients with different degrees of arterial insufficiency (n = 36). During day hours the calculated subcutaneous blood flow in the forefoot was on a...... claudication. In patients with severe ischaemia, i.e. having rest pain, the blood flow decreased by approximately 50%. The changes in local blood flow may be due to changes in local sympathetic tone and to changes in local perfusion pressure.......Twenty-four hour continuous recording of xenon (133Xe) wash-out from the forefoot was performed on patients with normal circulations (n = 10) and on patients with different degrees of arterial insufficiency (n = 36). During day hours the calculated subcutaneous blood flow in the forefoot...... was on average the same in patients with normal circulations and in patients with different degrees of arterial insufficiency (mean: 2.0 +/- 0.8 ml min-1 100 g-1). During sleep the blood flow nearly doubled in patients with normal circulations; no systematic change was seen in patients with intermittent...

  19. Strength training reduces arterial blood pressure but not sympathetic neural activity in young normotensive subjects

    Science.gov (United States)

    Carter, Jason R.; Ray, Chester A.; Downs, Emily M.; Cooke, William H.

    2003-01-01

    The effects of resistance training on arterial blood pressure and muscle sympathetic nerve activity (MSNA) at rest have not been established. Although endurance training is commonly recommended to lower arterial blood pressure, it is not known whether similar adaptations occur with resistance training. Therefore, we tested the hypothesis that whole body resistance training reduces arterial blood pressure at rest, with concomitant reductions in MSNA. Twelve young [21 +/- 0.3 (SE) yr] subjects underwent a program of whole body resistance training 3 days/wk for 8 wk. Resting arterial blood pressure (n = 12; automated sphygmomanometer) and MSNA (n = 8; peroneal nerve microneurography) were measured during a 5-min period of supine rest before and after exercise training. Thirteen additional young (21 +/- 0.8 yr) subjects served as controls. Resistance training significantly increased one-repetition maximum values in all trained muscle groups (P training did not affect MSNA or heart rate. Arterial blood pressures and MSNA were unchanged, but heart rate increased after 8 wk of relative inactivity for subjects in the control group (61 +/- 2 to 67 +/- 3 beats/min; P = 0.01). These results indicate that whole body resistance exercise training might decrease the risk for development of cardiovascular disease by lowering arterial blood pressure but that reductions of pressure are not coupled to resistance exercise-induced decreases of sympathetic tone.

  20. Event-Based Tone Mapping for Asynchronous Time-Based Image Sensor.

    Science.gov (United States)

    Simon Chane, Camille; Ieng, Sio-Hoi; Posch, Christoph; Benosman, Ryad B

    2016-01-01

    The asynchronous time-based neuromorphic image sensor ATIS is an array of autonomously operating pixels able to encode luminance information with an exceptionally high dynamic range (>143 dB). This paper introduces an event-based methodology to display data from this type of event-based imagers, taking into account the large dynamic range and high temporal accuracy that go beyond available mainstream display technologies. We introduce an event-based tone mapping methodology for asynchronously acquired time encoded gray-level data. A global and a local tone mapping operator are proposed. Both are designed to operate on a stream of incoming events rather than on time frame windows. Experimental results on real outdoor scenes are presented to evaluate the performance of the tone mapping operators in terms of quality, temporal stability, adaptation capability, and computational time. PMID:27642275

  1. Tone model integration based on discriminative weight training for Putonghua speech recognition

    Institute of Scientific and Technical Information of China (English)

    HUANG Hao; ZHU Jie

    2008-01-01

    A discriminative framework of tone model integration in continuous speech recognition was proposed. The method uses model dependent weights to scale probabilities of the hidden Markov models based on spectral features and tone models based on tonal features.The weights are discriminatively trahined by minimum phone error criterion. Update equation of the model weights based on extended Baum-Welch algorithm is derived. Various schemes of model weight combination are evaluated and a smoothing technique is introduced to make training robust to over fitting. The proposed method is ewluated on tonal syllable output and character output speech recognition tasks. The experimental results show the proposed method has obtained 9.5% and 4.7% relative error reduction than global weight on the two tasks due to a better interpolation of the given models. This proves the effectiveness of discriminative trained model weights for tone model integration.

  2. Impact of Rhythm on Vietnamese Adult EFL Learners Intelligibility in Term of Mid-level Tone

    Directory of Open Access Journals (Sweden)

    Tien DANG

    2013-07-01

    Full Text Available This study investigates the impact of L1 (Vietnamese on L2 (English with a specific reference to rhythm. The transfer of L1 rhythm to the L2 rhythm is considered as a potential factor in reducing EFL learner’s intelligibility.  The findings of this quantitative research show that Vietnamese adult EFL learners’ oral output is significantly unintelligible due to the application the mid-level tone of their first language, part of Vietnamese rhythm to produce English rhythm in a pronunciation test, making their utterance monotonous. This paper aims at presenting findings gained from an examination into how the Vietnamese rhythm, the mid-level tone, affects 50 Vietnamese adult EFL learners’ intelligibility in a pronunciation test assessed by ten judges. Key words: rhythm, mid-level tone, Vietnamese adult EFL learners, and intelligibility

  3. Modeling two-tone suppression and distortion product on basilar membrane

    Science.gov (United States)

    Murakami, Yasuki; Ishimitsu, Shunsuke

    2015-12-01

    This paper reveals mechanisms of two-tone suppression (2TS) and distortion product (DP) on the basilar membrane (BM) using a model. Computational simulation is conducted with an active and nonlinear transmission line model including a nonlinear outer hair cell model that shows compressive property in two dimensionally where two tones are input. To evaluate the cochlear model, over all responses of BM model are used. For simultaneous input pairs, the response is suppressed by a stronger tone, or distorted where levels of a pair are equaled. Cubic distortion produced by a simple nonlinear feedback system including the OHC model appears similar to DPs in the cochlear model. These results suggest that two dimensional property of the OHC and its feedback generate 2TS and DPs. This further suggests the importance of the overall responses for investigating mechanisms of cochlear nonlinearities without fluid coupling in the cochlea.

  4. IBM-JSR 193-nm negative tone resist: polymer design, material properties, and lithographic performance

    Science.gov (United States)

    Patel, Kaushal S.; Lawson, Margaret C.; Varanasi, Pushkara Rao; Medeiros, David R.; Wallraff, Gregory M.; Brock, Phillip J.; DiPietro, Richard A.; Nishimura, Yukio; Chiba, Takashi; Slezak, Mark

    2004-05-01

    It has been previously proposed that negative-tone resist process would have an intrinsic advantage for printing narrow trench geometry. To demonstrate this for 193nm lithography, a negative resist with performance comparable to a leading positive resist is required. In this paper we report the joint development of a hexafluoroalcohol containing, 193nm, negative-tone, chemically amplified resist based on the crosslinking approach. Lithographic performance is presented which includes the ability of the negative-tone resist to print 90nm line/space and isolated trenches with standard resist processing. The impact of the fluorinated polymer on etch performance is also quantified. Finally, key resist characteristics and their influence on performance and limiting factors such as microbridging are discussed.

  5. Effect of LSVT on Lexical Tone in Speakers with Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Tara L. Whitehill

    2011-01-01

    Full Text Available Lee Silverman Voice Treatment (LSVT has well-documented treatment efficacy for individuals with hypokinetic dysarthria associated with Parkinson's disease (PD. Positive changes have been noted after treatment not only for vocal loudness but also for many other speech dimensions, including intonation (monotonicity. There have been few studies investigating the effect of LSVT on lexical tone which, like intonation, is controlled by variations in fundamental frequency. This study involved 12 Cantonese speakers with idiopathic PD who were enrolled in a standard LVST treatment protocol. Speech data were collected 3-4 days before treatment and 1 day after treatment. A wide variety of perceptual and acoustic variables were analyzed. The results showed significant improvements in loudness and intonation after treatment, but no significant changes in lexical tone. These results have theoretical implications for the relationship between tone and intonation and for models of the physiological control of fundamental frequency.

  6. Lexical prosody beyond first-language boundary: Chinese lexical tone sensitivity predicts English reading comprehension.

    Science.gov (United States)

    Choi, William; Tong, Xiuli; Cain, Kate

    2016-08-01

    This 1-year longitudinal study examined the role of Cantonese lexical tone sensitivity in predicting English reading comprehension and the pathways underlying their relation. Multiple measures of Cantonese lexical tone sensitivity, English lexical stress sensitivity, Cantonese segmental phonological awareness, general auditory sensitivity, English word reading, and English reading comprehension were administered to 133 Cantonese-English unbalanced bilingual second graders. Structural equation modeling analysis identified transfer of Cantonese lexical tone sensitivity to English reading comprehension. This transfer was realized through a direct pathway via English stress sensitivity and also an indirect pathway via English word reading. These results suggest that prosodic sensitivity is an important factor influencing English reading comprehension and that it needs to be incorporated into theoretical accounts of reading comprehension across languages.

  7. Problems in Mandarin Tone Acquisition by American Students--The Interference of American English Intonation Patterns

    Institute of Scientific and Technical Information of China (English)

    Ming Chao Gui

    2000-01-01

    It is intended in this paper to discuss the common patterns of American intonation that interfere the tone acquisition by American students. Similar to the linguistic phenomenon that nonnative speakers of English speak the language with foreign accent due to the influence and linguistic constraints of their own mother tongue, American students face interference from the intonation patterns of American English in their acquisition of tones in the study of Mandarin Chinese. The syntactic structure that most clearly reflects this fact is the two-syllable Chinese word groups. After a close study of the most common mistakes made by American students in .their study of Mandarin tones, some general patterns are observed. It is concluded that the major causes of these mistakes could be attributed to English intonation pattems on the same level of syntactic structure

  8. A tone-aided dual vestigial sideband system for digital communications on fading channels

    Science.gov (United States)

    Hladik, Stephen M.; Saulnier, Gary J.; Rafferty, William

    1989-01-01

    A spectrally efficient tone-aided dual vestigial sideband (TA/DVSB) system for digital data communications on fading channels is presented and described analytically. This PSK (phase-shift-keying) system incorporates a feed-forward, tone-aided demodulation technique to compensate for Doppler frequency shift and channel- induced, multipath fading. In contrast to other tone-in-band-type systems, receiver synchronization is derived from the complete data VSBs. Simulation results for the Rician fading channel are presented. These results demonstrate the receiver's ability to mitigate performance degradation due to fading and to obtain proper data carrier synchronization, suggesting that the proposed TA/DVSB system has promise for this application. Simulated BER (bit-error rate) data indicate that the TA/DVSB system effectively alleviates the channel distortions of the land mobile satellite application.

  9. Data Compression for Video-Conferencing using Half tone and Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Dr. H.B.Kekre

    2013-01-01

    Full Text Available Overhead of data transmission over internet is increasing exponentially every day. Optimization of natural bandwidth is the basic motive by compressing image data to the maximum extend. For the same objective, combination of lossy half tone and lossless Wavelet Transform techniques is proposed so as to obtain low-bit rate video data transmission. Decimal values of bitmapped image are to be converted into either 1 or 0 in half toning process that incur pictorial loss and gives 8:1 compression ratio (CR irrespective of image. Wavelet Transform is applied on half tone image for higher compression for various levels. An experimental result shows the higher CR, minimum Mean Square Error (MSE. Ten sample images of different people captured by Nikon camera are used for experimentation.All images are bitmap (.BMP 512 X 512 in size. The proposed technique can be used for video conferencing, storage of movies and CCTV footage etc.

  10. Lexical prosody beyond first-language boundary: Chinese lexical tone sensitivity predicts English reading comprehension.

    Science.gov (United States)

    Choi, William; Tong, Xiuli; Cain, Kate

    2016-08-01

    This 1-year longitudinal study examined the role of Cantonese lexical tone sensitivity in predicting English reading comprehension and the pathways underlying their relation. Multiple measures of Cantonese lexical tone sensitivity, English lexical stress sensitivity, Cantonese segmental phonological awareness, general auditory sensitivity, English word reading, and English reading comprehension were administered to 133 Cantonese-English unbalanced bilingual second graders. Structural equation modeling analysis identified transfer of Cantonese lexical tone sensitivity to English reading comprehension. This transfer was realized through a direct pathway via English stress sensitivity and also an indirect pathway via English word reading. These results suggest that prosodic sensitivity is an important factor influencing English reading comprehension and that it needs to be incorporated into theoretical accounts of reading comprehension across languages. PMID:27135168

  11. PHYSIOLOGICAL MENSTRUAL RHYTHM AND FERTILITY AFTER INTERNAL ILIAC ARTERY LIGATION

    Directory of Open Access Journals (Sweden)

    Sunaina

    2015-11-01

    Full Text Available AIMS AND OBJECTIVE Bilateral internal iliac artery ligation is a useful skill for the management of life-threatening post-partum hemorrhage. The procedure is not without risks and long-term complications. This study was conducted to ensure documentation and reporting of pregnancies following bilateral hypogastric artery ligation in cases of post-partum hemorrhage. We also aimed to compare the menstrual function and reproductive outcome after bilateral internal iliac artery ligation done for atonic post-partum haemorrhage. DESIGN Prospective Case Study. SETTING Department of Obstetrics and Gynaecology, Institute of Obstetrics and Gynaecology, Madras Medical College and Hospital, Chennai, Jan 2013 to March 2015. PARTICIPANTS Ten cases of bilateral internal iliac artery ligation were done for atonic post-partum hemorrhage. Main outcome measures: The primary outcome was assessed as the resumption of menstruation, regular cycles, and ability to conceive after surgery. Secondary outcome was incidence of intrauterine growth retardation and recurrent post-partum hemorrhage in subsequent pregnancies. RESULTS The mean duration of resumption of menstruation following internal iliac artery ligation was 3 months. Bilateral internal iliac artery ligation is preferred over unilateral ligation as the extensive collaterals from the contralateral side immediately fill the circulation. The cases of atonic post-partum hemorrhage may require B-Lynch sutures in addition to bilateral internal iliac artery ligation to regain tone. Successful pregnancy after bilateral internal iliac artery ligation occurred in three out of seven cases. In one case, there was intrauterine growth retardation in eighth month. The patient was admitted and closely monitored with Doppler scan. At 35 weeks of gestation, emergency lower segment caesarean section was done for absent diastolic flow. The preterm neonate was 2 kilograms. There was no post-partum hemorrhage in the subsequent

  12. The Siren's Song: Exploitation of Female Flight Tones to Passively Capture Male Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Johnson, Brian J; Ritchie, Scott A

    2016-01-01

    The need to capture male mosquitoes has intensified recently as a result of a number of male-based sterile insect technique (SIT) and population-modification programs focused on Aedes aegypti (L.) having initiated field releases. Here, we report the results of the successful exploitation of the attraction of male Ae. aegypti to female flight tones to enhance male collections in nonmechanical passive (nonbattery powered) Gravid Aedes Traps (GAT). Prior to field studies, male attraction to female flight tones of 484 and 560 Hz, as well as to a male flight tone of 715 Hz, were assessed in a series of controlled release-recapture and semifield trials. These trials determined that a pure tone of 484 Hz was significantly more attractive to free-flying males than the other flight tones and enabled their collection in sound-baited GATs (ca. 95% capture rate after 2 h; 484 Hz at 65 dB). In contrast, gravid females were unresponsive to male or female flight tones and were evenly distributed among sound-baited and control GATs. Importantly, under normal field conditions sound-baited GATs (484 Hz at 70 dB) captured significantly more male Ae. aegypti per 24-h trap interval (1.3 ± 0.37) than controls (0.2 ± 0.13). Overall, sound-bated GATs captured approximately twice as many Ae. aegypti (male and female; 3.0 ± 0.68 per interval, 30 total) than controls (1.5 ± 0.56 per interval, 15 total). These results reveal that sound-baited GATs are a simple and effective surveillance tool for Ae. aegypti that would allow current male-based SIT and population-modification programs to effectively monitor males in their target populations. PMID:26502754

  13. The Siren's Song: Exploitation of Female Flight Tones to Passively Capture Male Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Johnson, Brian J; Ritchie, Scott A

    2016-01-01

    The need to capture male mosquitoes has intensified recently as a result of a number of male-based sterile insect technique (SIT) and population-modification programs focused on Aedes aegypti (L.) having initiated field releases. Here, we report the results of the successful exploitation of the attraction of male Ae. aegypti to female flight tones to enhance male collections in nonmechanical passive (nonbattery powered) Gravid Aedes Traps (GAT). Prior to field studies, male attraction to female flight tones of 484 and 560 Hz, as well as to a male flight tone of 715 Hz, were assessed in a series of controlled release-recapture and semifield trials. These trials determined that a pure tone of 484 Hz was significantly more attractive to free-flying males than the other flight tones and enabled their collection in sound-baited GATs (ca. 95% capture rate after 2 h; 484 Hz at 65 dB). In contrast, gravid females were unresponsive to male or female flight tones and were evenly distributed among sound-baited and control GATs. Importantly, under normal field conditions sound-baited GATs (484 Hz at 70 dB) captured significantly more male Ae. aegypti per 24-h trap interval (1.3 ± 0.37) than controls (0.2 ± 0.13). Overall, sound-bated GATs captured approximately twice as many Ae. aegypti (male and female; 3.0 ± 0.68 per interval, 30 total) than controls (1.5 ± 0.56 per interval, 15 total). These results reveal that sound-baited GATs are a simple and effective surveillance tool for Ae. aegypti that would allow current male-based SIT and population-modification programs to effectively monitor males in their target populations.

  14. [Splenic artery aneurysms].

    Science.gov (United States)

    Colović, R; Davidović, L; Bilanović, D; Krivokapić, Z; Grubor, N; Cvetković, S; Radak, V; Marković, M

    2006-01-01

    Although the third most frequent aneurysm in the abdomen, after aneurysms of the aorta and iliac arteries, and most frequent aneurisms of visceral arteries, splenic artery aneurysms are rare, but not very rare. Thanks to the new imaging techniques, first of all ultrasonography, they have been discovered with increasing frequency. We present a series of 9 splenic artery aneurysms. Seven patients were female and two male of average age 49 years (ranging from 28 to 75 years). The majority of afected women were multiparae, with average 3 children (ranging from 1 to 6). One patient had a subacute rupture, and 2 had ruptures into the splenic vein causing portal hypertension. The spleen was enlarged in 7 out of 9 patients. The average size of aneurysms was 3,2 cm (ranging from 2 to 8 cm). The preoperative diagnosis of splenic artery aneurysm was established in 6 patients while in 3 patients aneurism was accidentally found during other operations, during splenectomy in 2, and during the excision of a retroperitoneal tumour in 1 patient. Aneurysmectomy was carried out in 7 patients, while a ligation of the incoming and outcoming wessels was performed in 2 patients with arteriovenous fistula. Splenectomy was performed in 6 patients, while pancreatic tail resection, cholecystectomy and excision of the retroperitoneal tumor were performed in 3 patients. Additional resection of the abdominal aortic aneurysm with reconstruction of aortoiliac segment was performed in 2 patients. There were no mortality and the postoperative recovery was uneventful in all patients. PMID:16989145

  15. BILATERAL DUPLICATION OF RENAL ARTERIES

    Directory of Open Access Journals (Sweden)

    Prajkta A Thete

    2014-09-01

    Full Text Available Routine dissection of a male cadaver revealed the presence of bilateral double renal arteries. On the right side the accessory renal artery originated from the abdominal aorta just above the main renal artery. On the left side the accessory renal artery originated from the abdominal aorta about 1 cm above the main renal artery. Knowledge of the variations of renal vascular anatomy has importance in exploration and treatment of renal trauma, renal transplantation, renal artery embolization, surgery for abdominal aortic aneurysm and conservative or radical renal surgery

  16. Generation of tone burst laser ultrasonic waves and its acoustic nonlinearity

    International Nuclear Information System (INIS)

    Optical system for generating tone burst ultrasonic wave is introduced and the actual waveform is demonstrated. 4 high power pulse lasers were used for excitation and the stabilized Michelson laser interferometer was used as detection. On the other hand, we tried to investigate the nonlinear acoustic effect of the generated tone burst laser ultrasonic wave. In thermo-elastic region, the nonlinearity did not appear because the absolute amplitude of ultrasonic wave was so small less than 0.5 nm. Whereas, in ablation region, fairly strong nonlinearity appeared because the absolute amplitude of receiving signal was quite large up to about 2 nm.

  17. The pitch of vibrato tones: a model based on instantaneous frequency decomposition.

    Science.gov (United States)

    Mesz, Bruno A; Eguia, Manuel C

    2009-07-01

    We study vibrato as the more ubiquitous manifestation of a nonstationary tone that can evoke a single overall pitch. Some recent results using nonsymmetrical vibrato tones suggest that the perceived pitch could be governed by some stability-sensitive mechanism. For nonstationary sounds the adequate tools are time-frequency representations (TFRs). We show that a recently proposed TFR could be the simplest framework to explain this hypothetical stability-sensitive mechanism. We propose a one-parameter model within this framework that is able to predict previously reported results and we present new results obtained from psychophysical experiments performed in our laboratory. PMID:19673767

  18. Edge-guided filtering scheme for decomposition-based tone mapping

    Science.gov (United States)

    Wu, Xuebiao; Su, Zhuo; Luo, Xiaonan

    2014-01-01

    This paper presents a novel edge-guided filtering scheme for decomposition-based tone mapping, whose superiority is to prevent two major defects in filter-driven multi-scale decomposition: halo artifact and over-smoothing distortion. First, we calculate an edge-preserving smoothing by gradient domain reconstruction with given edges. Then we apply this output in high dynamic range tone mapping to address aforementioned problems. At last, some experimental results are presented to demonstrate the effectiveness of our method in producing high-quality low dynamic range outputs.

  19. Active noise control to reduce the blade tone noise of centrifugal fans

    Science.gov (United States)

    Koopmann, G. H.; Neise, W.; Chen, W.

    1988-07-01

    An active noise control method for suppressing the blade tones of centrifugal fans is presented which uses two secondary sound sources mounted into the cutoff region of the fan casing. Experiments were conducted for centrifugal fans with impeller diameters between 280 and 710 mm using two different designs for the secondary sources. The results indicate that the sound field inside the casing is dominated by the rotor locked pressure field, and that the blade tone noise measured in the far-field is generated by the unsteady pressures at the cutoff, which in turn are produced by the flow leaving the impeller.

  20. Anomalous right coronary artery arising from left anterior descending artery

    Directory of Open Access Journals (Sweden)

    M.L. Sreenivas Kumar

    2012-07-01

    Full Text Available A 54-year-old male patient presented with acute myocardial infarction involving left anterior descending and right coronary artery territories. Coronary angiogram showed a single coronary artery with right coronary artery arising from left anterior descending artery (LAD, which coursed anterior to right ventricular outflow tract and thrombotic lesion in mid left anterior descending artery before origin of right coronary artery. The patient was treated with thrombolytic therapy and glycoprotein IIb/IIIa inhibitors. Anomalous origin of right coronary artery as a branch of LAD is a very rare type of congenital coronary artery anomalies. It is important to recognize this anomaly as it can be associated with extensive myocardial ischemia and sudden cardiac death in young persons even without atherosclerosis.

  1. Orientations professionnelles atypiques : transgression des normes de genre et effets identitaires

    OpenAIRE

    Gianettoni, Lavinia; Simon-Vermot, Pierre; Gauthier, Jacques-Antoine

    2011-01-01

    Par le biais d’analyses secondaires des données longitudinales suisses issues de l’étude « Transition entre l’école et l’emploi », cet article analyse les effets des aspirations professionnelles atypiques du point de vue du genre et de l’exercice d’une profession atypique sur l’identité des jeunes et leur conformisme aux rôles sexués. Les résultats montrent que les filles aspirent plus que les garçons à exercer des métiers majoritairement occupés par le sexe opposé, mais ont beaucoup moins de...

  2. Effet du glaucome et des facteurs de risque de glaucome sur l'hémodynamique choroïdienne

    OpenAIRE

    Abou Samra, Waleed Ali

    2007-01-01

    Dans la présente étude, nous avons évalué quantitativement l'hémodynamique de la circulation choroïdienne subfovéolaire chez des patients atteints de glaucome à angle ouvert et des patients présentant un hypertension oculaire. Nous avons étudié l'effet des facteurs de risque du glaucome sur la circulation choroïdienne subfoveale en vue de déterminer le rôle de cette circulation dans la pathogénie de cette maladie. De plus, nous avons établi les relations entre les paramètres hémodynamiques et...

  3. Effet sur la compétitivité des réglementations relatives à la gestion des effluents

    DEFF Research Database (Denmark)

    Andersen, Mikael Skou

    2004-01-01

    Grâce à un regard approfondi sur le secteur laitier dans les pays de l'OCDE, cette étude permet de mieux analyser l'impact des subventions à l'agriculture et des politiques de l'environnement sur l'environnement et sur la compétitivité internationale des produits laitiers. Ce chapitre étudie les...... effets des réglementations relatives à l’environnement sur la compétitivité des éleveurs laitiers de six pays de l’OCDE : le Canada, le Danemark, le Japon, la Nouvelle-Zélande, les PaysBas et la Suisse. Ces pays ont été choisis parce qu’ils représentent les principales régions productrices de lait de l...

  4. Effets de l'étrépage pour la restauration de landes tourbeuses en haute Ardenne belge

    OpenAIRE

    Jacquemart, Anne-Laure; De Sloover, Jacques

    2008-01-01

    En 1989, la restauration par éùépage de landes lourbeuses dégradées et envahies par Molinia caerulea a été enlrcprise en hauie Ardenne belge Des relevés de véqétation ont été effectués en 'i989 et en 1998 l'étrépage â un effet bénéfique en diminuant le couvert de la molinie et en augmentant celui des espèces lypiques des landes tourbeuses telles que Juncus sq-uaffosus, Carex panicea, Erica tetralix, Trichophorum cespitosun el Narthecium assifragum féirépâqe a égaleûrenl permis le retour d'esp...

  5. Définir les choix à risque: l'éthique et les effets des décisions organisationnelles.

    Science.gov (United States)

    Warren, Marika

    2016-07-01

    Les choix de vivre « à risque » sont complexes et difficiles. Ils peuvent être structurés par les politiques organisationnelles. Certaines personnes veulent vraiment vivre dans des situations à haut risque ou perçues comme telles parce qu'elles en tirent un avantage important. Cependant, il est probable que ces choix dépendent en grande partie du contexte et qu'ils ne se soient pas posés dans une autre situation. L'article plaide pour la responsabilité d'être attentif aux effets des décisions organisationnelles sur les choix de vivre à risque et sur la répartition globale du risque. PMID:27365384

  6. A Tale of Two Features: Perception of Cantonese Lexical Tone and English Lexical Stress in Cantonese-English Bilinguals.

    Science.gov (United States)

    Tong, Xiuli; Lee, Stephen Man Kit; Lee, Meg Mei Ling; Burnham, Denis

    2015-01-01

    This study investigated the similarities and differences in perception of Cantonese tones and English stress patterns by Cantonese-English bilingual children, adults, and English monolingual adults. All three groups were asked to discriminate pairs of syllables that minimally differed in either Cantonese tone or in English stress. Bilingual children's performance on tone perception was comparable to their performance on stress perception. By contrast, bilingual adults' performance on tone perception was lower than their performance on stress perception, and there was a similar pattern in English monolingual adults. Bilingual adults tended to perform better than English monolingual adults on both the tone and stress perception tests. A significant correlation between tone perception and stress perception performance was found in bilingual children but not in bilingual adults. All three groups showed lower accuracy in the high rising-low rising contrast than any of the other 14 Cantonese tone contrasts. The acoustic analyses revealed that average F0, F0 onset, and F0 major slope were the critical acoustic correlates of Cantonese tones, whereas multiple acoustic correlates were salient in English stress, including average F0, spectral balance, duration and intensity. We argue that participants' difficulty in perceiving high rising-low rising contrasts originated from the contrasts' similarities in F0 onset and average F0; indeed the difference between their major slopes was the only cue with which to distinguish them. Acoustic-perceptual correlation analyses showed that although the average F0 and F0 onset were associated with tone perception performance in all three groups, F0 major slope was only associated with tone perception in the bilingual adult group. These results support a dynamic interactive account of suprasegmental speech perception by emphasizing the positive prosodic transfer between Cantonese tone and English stress, and the role that level of

  7. Limits on Monolingualism? A comparison of monolingual and bilingual infants’ abilities to integrate lexical tone in novel word learning.

    Directory of Open Access Journals (Sweden)

    Leher eSingh

    2016-05-01

    Full Text Available To construct their first lexicon, infants must determine the relationship between native phonological variation and the meanings of words. This process is arguably more complex for bilingual learners who are often confronted with phonological conflict: phonological variation that is lexically relevant in one language may be lexically irrelevant in the other. In a series of four experiments, the present study investigated English-Mandarin bilingual infants’ abilities to negotiate phonological conflict introduced by learning both a tone and a non-tone language. In a novel word learning task, bilingual children were tested on their sensitivity to tone variation in English and Mandarin contexts. Their abilities to interpret tone variation in a language-dependent manner were compared to those of monolingual Mandarin learning infants. Results demonstrated that at 12 to 13 months, bilingual infants demonstrated the ability to bind tone to word meanings in Mandarin, but to disregard tone variation when learning new words in English. In contrast, monolingual learners of Mandarin did not show evidence of integrating tones into word meanings in Mandarin at the same age even though they were learning a tone language. However, a tone discrimination paradigm confirmed that monolingual Mandarin learning infants were able to tell these tones apart at 12 to 13 months under a different set of conditions. Later, at 17 to 18 months, monolingual Mandarin learners were able to bind tone variation to word meanings when learning new words. Our findings are discussed in terms of cognitive adaptations associated with bilingualism that may ease the negotiation of phonological conflict and facilitate precocious uptake of certain properties of each language.

  8. Limits on Monolingualism? A Comparison of Monolingual and Bilingual Infants' Abilities to Integrate Lexical Tone in Novel Word Learning.

    Science.gov (United States)

    Singh, Leher; Poh, Felicia L S; Fu, Charlene S L

    2016-01-01

    To construct their first lexicon, infants must determine the relationship between native phonological variation and the meanings of words. This process is arguably more complex for bilingual learners who are often confronted with phonological conflict: phonological variation that is lexically relevant in one language may be lexically irrelevant in the other. In a series of four experiments, the present study investigated English-Mandarin bilingual infants' abilities to negotiate phonological conflict introduced by learning both a tone and a non-tone language. In a novel word learning task, bilingual children were tested on their sensitivity to tone variation in English and Mandarin contexts. Their abilities to interpret tone variation in a language-dependent manner were compared to those of monolingual Mandarin learning infants. Results demonstrated that at 12-13 months, bilingual infants demonstrated the ability to bind tone to word meanings in Mandarin, but to disregard tone variation when learning new words in English. In contrast, monolingual learners of Mandarin did not show evidence of integrating tones into word meanings in Mandarin at the same age even though they were learning a tone language. However, a tone discrimination paradigm confirmed that monolingual Mandarin learning infants were able to tell these tones apart at 12-13 months under a different set of conditions. Later, at 17-18 months, monolingual Mandarin learners were able to bind tone variation to word meanings when learning new words. Our findings are discussed in terms of cognitive adaptations associated with bilingualism that may ease the negotiation of phonological conflict and facilitate precocious uptake of certain properties of each language. PMID:27242584

  9. Arterial hypertension and cancer.

    Science.gov (United States)

    Milan, Alberto; Puglisi, Elisabetta; Ferrari, Laura; Bruno, Giulia; Losano, Isabel; Veglio, Franco

    2014-05-15

    Arterial hypertension and cancer are two of the most important causes of mortality in the world; correlations between these two clinical entities are complex and various. Cancer therapy using old (e.g., mitotic spindle poisons) as well as new (e.g., monoclonal antibody) drugs may cause arterial hypertension through different mechanisms; sometimes the increase of blood pressure levels may be responsible for chemotherapy withdrawal. Among newer cancer therapies, drugs interacting with the VEGF (vascular endothelial growth factors) pathways are the most frequently involved in hypertension development. However, many retrospective studies have suggested a relationship between antihypertensive treatment and risk of cancer, raising vast public concern. The purposes of this brief review have then been to analyse the role of chemotherapy in the pathogenesis of hypertension, to summarize the general rules of arterial hypertension management in this field and finally to evaluate the effects of antihypertensive therapy on cancer disease.

  10. Pharmacological modulation of arterial stiffness.

    LENUS (Irish Health Repository)

    Boutouyrie, Pierre

    2011-09-10

    Arterial stiffness has emerged as an important marker of cardiovascular risk in various populations and reflects the cumulative effect of cardiovascular risk factors on large arteries, which in turn is modulated by genetic background. Arterial stiffness is determined by the composition of the arterial wall and the arrangement of these components, and can be studied in humans non-invasively. Age and distending pressure are two major factors influencing large artery stiffness. Change in arterial stiffness with drugs is an important endpoint in clinical trials, although evidence for arterial stiffness as a therapeutic target still needs to be confirmed. Drugs that independently affect arterial stiffness include antihypertensive drugs, mostly blockers of the renin-angiotensin-aldosterone system, hormone replacement therapy and some antidiabetic drugs such as glitazones. While the quest continues for \\'de-stiffening drugs\\

  11. Ischemia as a potential etiologic factor in idiopathic unilateral sudden sensorineural hearing loss: Analysis of posterior circulation arteries.

    Science.gov (United States)

    Kim, Chulho; Sohn, Jong-Hee; Jang, Min Uk; Hong, Sung-Kwang; Lee, Joong-Seob; Kim, Hyung-Jong; Choi, Hui-Chul; Lee, Jun Ho

    2016-01-01

    The association between idiopathic sudden sensorineural hearing loss (ISSNHL) and the radiologic characteristics of the vertebrobasilar artery is unclear. We hypothesized that the degree and direction of vertebrobasilar artery curvature in the posterior circulation contribute to the occurrence of ISSNHL. We consecutively enrolled patients diagnosed with unilateral ISSNHL in two tertiary hospitals. Magnetic resonance images were performed in all patients to exclude specific causes of ISSNHL, such as vestibular schwannoma, chronic mastoiditis, and anterior inferior cerebellar artery infarct. We measured the following parameters of posterior circulation: vertebral and basilar artery diameter, the degree of basilar artery curvature (modified smoker criteria), and vertebral artery dominance. Pure tone audiometries were performed at admission and again 1 week and 3 months later. A total of 121 ISSNHL patients (mean age, 46.0 ± 17.3 years; 48.8% male) were included in these analyses. The proportion of patients with the left side hearing loss was larger than the proportion with the right side hearing loss (left, 57.9%; right, 42.1%). The majority of patients were characterized by a left dominant vertebral artery and right-sided basilar artery curvature. The direction of the basilar artery curvature was significantly associated with hearing loss lateralization (p = 0.036). Age and sex matched multivariable analyses revealed the absence of diabetes and right-sided basilar artery curvature as significant predictors for left sided hearing loss. There was no statistical difference between atherosclerotic cardiovascular risk score (high versus low) and hearing outcomes at 3 months. In ISSNHL, the laterality of hearing loss was inversely associated with the direction of basilar artery curvature. Our results, therefore, indicate the importance of vascular assessment when evaluating ISSNHL.

  12. Mechanisms of endothelial dysfunction in resistance arteries from patients with end-stage renal disease.

    Directory of Open Access Journals (Sweden)

    Leanid Luksha

    Full Text Available The study focuses on the mechanisms of endothelial dysfunction in the uremic milieu. Subcutaneous resistance arteries from 35 end-stage renal disease (ESRD patients and 28 matched controls were studied ex-vivo. Basal and receptor-dependent effects of endothelium-derived factors, expression of endothelial NO synthase (eNOS, prerequisites for myoendothelial gap junctions (MEGJ, and associations between endothelium-dependent responses and plasma levels of endothelial dysfunction markers were assessed. The contribution of endothelium-derived hyperpolarizing factor (EDHF to endothelium-dependent relaxation was impaired in uremic arteries after stimulation with bradykinin, but not acetylcholine, reflecting the agonist-specific differences. Diminished vasodilator influences of the endothelium on basal tone and enhanced plasma levels of asymmetrical dimethyl L-arginine (ADMA suggest impairment in NO-mediated regulation of uremic arteries. eNOS expression and contribution of MEGJs to EDHF type responses were unaltered. Plasma levels of ADMA were negatively associated with endothelium-dependent responses in uremic arteries. Preserved responses of smooth muscle to pinacidil and NO-donor indicate alterations within the endothelium and tolerance of vasodilator mechanisms to the uremic retention products at the level of smooth muscle. We conclude that both EDHF and NO pathways that control resistance artery tone are impaired in the uremic milieu. For the first time, we validate the alterations in EDHF type responses linked to kinin receptors in ESRD patients. The association between plasma ADMA concentrations and endothelial function in uremic resistance vasculature may have diagnostic and future therapeutic implications.

  13. Combination of rare right arterial variation with anomalous origins of the vertebral artery, aberrant subclavian artery and persistent trigeminal artery. A case report.

    Science.gov (United States)

    Ishihara, H; San Millán Ruíz, D; Abdo, G; Asakura, F; Yilmaz, H; Lovblad, K O; Rüfenacht, D A

    2011-09-01

    A 32-year-old woman hospitalized for subarachnoid hemorrhage showed rare arterial variation on the right side with anomalous origins of the vertebral artery, aberrant subclavian artery and persistent trigeminal artery. Angiography showed the right vertebral artery to originate from the right common carotid artery, the right subclavian artery to arise separately from the descending aorta, and persistent trigeminal artery on the right side. The possible embryonic mechanism of this previously unreported variant combination is discussed. PMID:22005696

  14. Liver cirrhosis and arterial hypertension

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Møller, Søren

    2006-01-01

    blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development...... of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most...

  15. Pulmonary artery sling: Case report

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Gil Hyun; Lee, Sun Wha; Cha, Sung Ho [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    1993-09-15

    Aberrant left-sided pulmonary artery(pulmonary artery sling) is an uncommon anomaly,which may cause significant respiratory abnormality. We report a case of pulmonary artery sling which is combined with persistent left superior vena cava and dextrocardia. This case were identified by esophagogram and CT and confirmed by MRI and angiography. We consider that MRI is a valuable new method for the diagnosis of aberrant left-sided pulmonary artery.

  16. "How, When, Why"--A Comparison of Two Action Research Methods to Examine the Hidden Tones in Annotation Feedback

    Science.gov (United States)

    Ball, Elaine; Regan, Paul

    2013-01-01

    This recent study broadly confirms earlier conclusions in which action research findings identified that annotated feedback on student assignments carried an unfavourable lecturer tone and, because of which, failed to motivate the student as a learner. It was important to take the action research process further to show how tone is so easily…

  17. BRAIN-STEM INFLUENCES ON BICEPS REFLEX ACTIVITY AND MUSCLE TONE IN THE ANESTHETIZED RAT

    NARCIS (Netherlands)

    JUCH, PJW; SCHAAFSMA, A; VANWILLIGEN, JD

    1992-01-01

    This study analyzes the effect of electrical stimulation of the locus coeruleus (LC) and adjacent brainstem structures on the tonic reflex (TVR), the tonic stretch reflex (TSR) and on muscle tone (MT) in anaesthetized rat. Increases in TVR. TSR and MT of the m. biceps were evoked from regions rostra

  18. Known-Groups and Concurrent Validity of the Mandarin Tone Identification Test (MTIT.

    Directory of Open Access Journals (Sweden)

    Shufeng Zhu

    Full Text Available The Mandarin Tone Identification Test (MTIT is a new test designed to assess the tone identification abilities of children with hearing impairment (HI. Evidence for reliability and sensitivity has been reported. The present study aimed to evaluate the known-groups and concurrent validity of the MTIT.The MTIT and Mandarin Pediatric Speech Intelligibility test (MPSI were administered in quiet and in noise conditions. The known-groups validity was evaluated by comparing the performance of the MTIT on children with two different levels of HI. The MPSI was included to evaluate the concurrent validity of the MTIT.81 children with HI were recruited in the present study. They were Mandarin-speaking children with profound HI (mean age = 9; 0, n = 41 and with moderate to severe HI (mean age = 8; 9, n = 40.Scores on the MTIT differed between the two groups with different hearing levels suggesting good known-groups validity. A strong relationship between tone and sentence perception both in quiet and in noise provided preliminary evidence for concurrent validity.The present study confirmed that the MTIT has good known-groups validity and provided preliminary evidence for concurrent validity. The MTIT could be used to evaluate tone identification ability in children with HI with confidence.

  19. High phase noise tolerant pilot-tone-aided DP-QPSK optical communication systems

    DEFF Research Database (Denmark)

    Zhang, Xu; Pang, Xiaodan; Deng, Lei;

    2012-01-01

    In this paper we experimentally demonstrate a novel, high phase-noise tolerant, optical dual polarization (DP) quadrature phase-shift keying (QPSK) communication system based on pilot-tone-aided phase noise cancellation (PNC) algorithm. Vertical cavity surface emitting lasers (VCSELs) with approx...

  20. Multi-tone parallel coherent matched detection for demultiplexing of superchannels.

    Science.gov (United States)

    Sakamoto, Takahide; Lu, Guo-Wei; Kawanishi, Tetsuya

    2013-08-12

    This paper presents multi-tone parallel coherent matched detection that orthogonally detects superchannels without crosstalk between neighboring channels. The receiver consists of multiple sets of multi-tone coherent matched detector employed in parallel. In each detector, the received superchannels signal is homodyne mixed in multi frequency with locally generated multi-tone optical frequency comb; detected is a signal set that has the amplitude and phase exactly matched with the local comb. By launching orthogonal sets of local comb to the multiple parallel coherent matched detectors, the received superchannels are orthogonally downconverted to the baseband frequencies keeping the amplitude and phase information of all channels included. With an aid of n × n transform matrix, all channels are separately recovered from the downconverted signal sets. The system does not rely on any optical filters for channel demultiplexing and separation, with increased flexibility in wavelength arrangement. In addition, the parallel configuration equivalently enhance the bandwidth of the coherent matched detector keeping the speed in each tributary channel as high as possible. In this paper, it is experimentally demonstrated that even-odd interleaved 23 × 20-Gb/s QPSK superchannels are orthogonally demultiplexed and detected by two-tone coherent matched detection. PMID:23938777

  1. Reduced Pelvic Floor Muscle Tone Predisposes to Persistence of Lower Urinary Tract Symptoms after Puerperium.

    Science.gov (United States)

    Bhat, Chandana; Khan, Mahjabeen; Ballala, Kirthinath; Kamath, Asha; Pandey, Deeksha

    2016-01-01

    Pregnant primiparous women at term were enrolled in the study. ICIQ-FLUTS questionnaire was used to find out prevalence of LUTS. MOS was used to assess pelvic floor muscle strength. Women were followed up after 8-10 weeks of delivery to find out remission or persistence of these symptoms. We found that increased frequency of micturition was the most common (82%) LUTS seen in primiparous women at term. More than half (51%) of these women who complained of LUTS had a poor pelvic floor muscle tone (MOS grade 3). Out of those who had symptoms during pregnancy 11% remained symptomatic even after puerperium. Interestingly 61% of those with persistence of symptoms demonstrated a very poor pelvic floor muscle tone at term (MOS grade 2), while the remaining 39% also had a tone of only MOS grade 3. Thus women with LUTS during pregnancy should be screened for their pelvic floor muscle tone with simple MOS system which will help to predict the persistence of these symptoms later on. Women with a low score (three or less) should be triaged for regular pelvic floor muscle exercises. PMID:27119044

  2. Time and frequency characteristics of temporary threshold shifts caused by pure tone exposures

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; Hammershøi, Dorte

    2011-01-01

    The time-frequency characteristics of Temporary Threshold Shifts (TTS) caused by pure tones were determined using the Békésy audiometric method with narrow-band noise of short duration as the probe stimuli. Two experiments were done using exposures of 3 min at 100 dB above threshold. In the first...

  3. Distortion-product otoacoustic emissions: body position effects with simultaneous presentation of tone pairs

    Directory of Open Access Journals (Sweden)

    Samuel R. Atcherson

    2011-11-01

    Full Text Available This study examined the effect of three different body positions on distortion-product otoacoustic emission (DPOAE amplitude and noise levels with multiple primary tone pairs simultaneously-presented to 36 normal-hearing female human adults. Other studies have demonstrated that the simultaneously presented tone pairs method shows clinical promise as a screener, but the sequential method remains in widespread clinical use. Postural changes have been suggested to have an effect not only on DPOAEs, but also transient-evoked OAEs and stimulus- frequency OAEs. DPOAE amplitude and noise levels were recorded in seated, supine, and side-lying positions to the following order of simultaneously-presented tone pairs relative to the f2 frequencies: 1187, 2375, and 4812 Hz; 1500, 3000, and 6062 Hz; and 1875, 3812, and 7625 Hz. No DPOAE could be detected reliably at 7625 Hz as result of poor signal-to-noise ratio. For remaining DPOAEs, statistical analyses revealed that amplitudes were not significantly different among the three body positions. However, at 1500 Hz and below, body position did have a statistically significant effect on noise levels though they are likely clinically negligible. Except at 7625 Hz, results suggest that DPOAEs recorded using a simultaneously presented tone pairs appear to be comparably recorded regardless of an individual’s body position.

  4. Physiology and Functioning: Parents' Vagal Tone, Emotion Socialization, and Children's Emotion Knowledge

    Science.gov (United States)

    Perlman, Susan B.; Camras, Linda A.; Pelphrey, Kevin A.

    2008-01-01

    This study examined relationships among parents' physiological regulation, their emotion socialization behaviors, and their children's emotion knowledge. Parents' resting cardiac vagal tone was measured, and parents provided information regarding their socialization behaviors and family emotional expressiveness. Their 4- or 5-year-old children (N…

  5. The ensemble variance of pure-tone measurements in reverberation rooms

    DEFF Research Database (Denmark)

    Jacobsen, Finn; Molares, Alfonso Rodriguez

    2010-01-01

    statistics of measurements in such rooms. Below the Schroeder frequency, the relative variance is much larger, particularly if the source emits a pure-tone. The established theory for this frequency range is based on ensemble statistics of modal sums and requires knowledge of mode shapes and the distribution...

  6. Brillouin optical time-domain analyzer based on orthogonally-polarized four-tone probe wave.

    Science.gov (United States)

    Hong, Xiaobin; Lin, Wenqiao; Yang, Zhisheng; Wang, Sheng; Wu, Jian

    2016-09-01

    The tolerance of the non-local effect in the BOTDA method using a dual-tone probe wave with fixed frequency separation is theoretically and experimentally investigated in this paper. The presented analysis points out that when the sensing fiber consists of two long fiber segments with large BFS difference (> 100 MHz), there will always be only one probe tone interacting with the pump pulse in the front fiber segment. Therefore, although the pulse distortion problem can still be overcome in this case, the conventional non-local effect would impose systematic error on the estimated BFS of the hotspot located at the end of the front fiber segment. For the purpose of avoiding the impact of non-local effect and eliminating the pump distortion problem simultaneously when using high probe power, a novel method based on a four-tone probe wave is proposed, in which the probe light consists of two pairs of orthogonally-polarized dual-tone probe waves with opposite frequency scanning direction. The experimental results demonstrate that the proposed method is capable of realizing 2 m spatial resolution over 104-km-long sensing fiber without the impact of non-local effect.

  7. A STUDY OF HEARING IMPROVEMENT AFTER TYMPANOPLASTY BY MEANS OF PURE TONE AUDIOMETRY

    Directory of Open Access Journals (Sweden)

    Siddharth Nirwan

    2015-01-01

    Full Text Available BACKGROUND : Chronic S uppurative O titis M edia (CSOM is an important cause of preventable hearing loss , particularly in the developing world. Tympanoplasty is a procedure to eradicate the disease in middle ear and to reconstruct hearing mechanism. Pure tone audiometry is an efficient , simple and economic tool to assess the level of postoperative hearing gain

  8. An Empirical Study on the Acquisition of English Rising Tone by Chinese EFL Learners

    Science.gov (United States)

    Chen, Wenkai

    2013-01-01

    Intonation is the melody and soul of speech, and plays an important role in oral communication. Nevertheless, the acquisition of English intonation by Chinese EFL learners is far from being satisfactory. It is found by empirical study that the main problems existing in acquiring English rising tone are improper placement of nucleus stress, failure…

  9. How to Study a Tone Language, with Exemplification from Oku (Grassfields Bantu, Cameroon)

    Science.gov (United States)

    Hyman, Larry M.

    2014-01-01

    In response to requests I have often got as to how one approaches a tone language, I present a personal view of the three stages involved, starting from scratch and arriving at an analysis: Stage I: Determining the tonal contrasts and their approximate phonetic allotones. Stage II: Discovering any tonal alternations ("morphotonemics").…

  10. Pre-attentive modulation of brain responses to tones in coloured-hearing synesthetes

    Directory of Open Access Journals (Sweden)

    Jäncke Lutz

    2012-12-01

    Full Text Available Abstract Background Coloured-hearing (CH synesthesia is a perceptual phenomenon in which an acoustic stimulus (the inducer initiates a concurrent colour perception (the concurrent. Individuals with CH synesthesia "see" colours when hearing tones, words, or music; this specific phenomenon suggesting a close relationship between auditory and visual representations. To date, it is still unknown whether the perception of colours is associated with a modulation of brain functions in the inducing brain area, namely in the auditory-related cortex and associated brain areas. In addition, there is an on-going debate as to whether attention to the inducer is necessarily required for eliciting a visual concurrent, or whether the latter can emerge in a pre-attentive fashion. Results By using the EEG technique in the context of a pre-attentive mismatch negativity (MMN paradigm, we show that the binding of tones and colours in CH synesthetes is associated with increased MMN amplitudes in response to deviant tones supposed to induce novel concurrent colour perceptions. Most notably, the increased MMN amplitudes we revealed in the CH synesthetes were associated with stronger intracerebral current densities originating from the auditory cortex, parietal cortex, and ventral visual areas. Conclusions The automatic binding of tones and colours in CH synesthetes is accompanied by an early pre-attentive process recruiting the auditory cortex, inferior and superior parietal lobules, as well as ventral occipital areas.

  11. Auditory Pattern Recognition and Brief Tone Discrimination of Children with Reading Disorders

    Science.gov (United States)

    Walker, Marianna M.; Givens, Gregg D.; Cranford, Jerry L.; Holbert, Don; Walker, Letitia

    2006-01-01

    Auditory pattern recognition skills in children with reading disorders were investigated using perceptual tests involving discrimination of frequency and duration tonal patterns. A behavioral test battery involving recognition of the pattern of presentation of tone triads was used in which individual components differed in either frequency or…

  12. Within-category variance and lexical tone discrimination in native and non-native speakers

    NARCIS (Netherlands)

    Hoffmann, C.W.G.; Sadakata, M.; Chen, A.; Desain, P.W.M.; McQueen, J.M.

    2014-01-01

    In this paper, we show how acoustic variance within lexical tones in disyllabic Mandarin Chinese pseudowords affects discrimination abilities in both native and non-native speakers of Mandarin Chinese. Within-category acoustic variance did not hinder native speakers in discriminating between lexical

  13. Reduced Pelvic Floor Muscle Tone Predisposes to Persistence of Lower Urinary Tract Symptoms after Puerperium

    Directory of Open Access Journals (Sweden)

    Chandana Bhat

    2016-01-01

    Full Text Available Pregnant primiparous women at term were enrolled in the study. ICIQ-FLUTS questionnaire was used to find out prevalence of LUTS. MOS was used to assess pelvic floor muscle strength. Women were followed up after 8–10 weeks of delivery to find out remission or persistence of these symptoms. We found that increased frequency of micturition was the most common (82% LUTS seen in primiparous women at term. More than half (51% of these women who complained of LUTS had a poor pelvic floor muscle tone (MOS grade 3. Out of those who had symptoms during pregnancy 11% remained symptomatic even after puerperium. Interestingly 61% of those with persistence of symptoms demonstrated a very poor pelvic floor muscle tone at term (MOS grade 2, while the remaining 39% also had a tone of only MOS grade 3. Thus women with LUTS during pregnancy should be screened for their pelvic floor muscle tone with simple MOS system which will help to predict the persistence of these symptoms later on. Women with a low score (three or less should be triaged for regular pelvic floor muscle exercises.

  14. Effect of Intensive Voice Treatment on Tone-Language Speakers with Parkinson's Disease

    Science.gov (United States)

    Whitehill, Tara L.; Wong, Lina L. -N.

    2007-01-01

    The aim of this study was to investigate the effect of intensive voice therapy on Cantonese speakers with Parkinson's disease. The effect of the treatment on lexical tone was of particular interest. Four Cantonese speakers with idiopathic Parkinson's disease received treatment based on the principles of Lee Silverman Voice Treatment (LSVT).…

  15. Effects of spontaneous otoacoustic emissions on pure-tone frequency difference limens

    DEFF Research Database (Denmark)

    Hansen, Rói; Santurette, Sébastien; Verhulst, Sarah

    2014-01-01

    Pure-tone frequency difference limens (FDLs) have been shown to vary in the vicinity of spontaneous otoacoustic emissions (SOAEs). As lower FDLs have been observed near SOAEs when measured ipsi- and contralaterally to the emission ear, it has been proposed that prolonged ongoing stimulation of ne...

  16. Exposure to extinction-associated contextual tone during slow-wave sleep and wakefulness differentially modulates fear expression.

    Science.gov (United States)

    Ai, Si-Zhi; Chen, Jie; Liu, Jian-Feng; He, Jia; Xue, Yan-Xue; Bao, Yan-Ping; Han, Fang; Tang, Xiang-Dong; Lu, Lin; Shi, Jie

    2015-09-01

    Recent research has used context cues (odor or auditory cues) to target memories during sleep and has demonstrated that they can enhance declarative and procedural memories. However, the effects of external cues re-presented during sleep on emotional memory are still not fully understood. In the present study, we conducted a Pavlovian fear conditioning/extinction paradigm and examined the effects of re-exposure to extinction memory associated contextual tones during slow-wave sleep (SWS) and wakefulness on fear expression. The participants underwent fear conditioning on the first day, during which colored squares served as the conditioned stimulus (CS) and a mild shock served as the unconditioned stimulus (US). The next day, they underwent extinction, during which the CSs were presented without the US but accompanied by a contextual tone (pink noise). Immediately after extinction, the participants were required to take a nap or remain awake and randomly assigned to six groups. Four of the groups were separately exposed to the associated tone (i.e. SWS-Tone group and Wake-Tone group) or an irrelevant tone (control tone, CtrT) (i.e. SWS-CtrT group and Wake-CtrT group), while the other two groups were not (i.e. SWS-No Tone group and Wake-No Tone group). Subsequently, the conditioned responses to the CSs were tested to evaluate the fear expression. All of the participants included in the final analysis showed successful levels of fear conditioning and extinction. During the recall test, the fear responses were significantly higher in the SWS-Tone group than that in the SWS-No Tone group or the SWS-CtrT group, while the Wake-Tone group exhibited more attenuated fear responses than either the Wake-No Tone group or Wake-CtrT group. Otherwise, re-exposure to auditory tones during SWS did not affect sleep profiles. These results suggest that distinct conditions during which re-exposure to an extinction memory associated contextual cue contributes to differential effects on

  17. The Perception of Musical Tones in the Statistical Sound Fields of Rooms.

    Science.gov (United States)

    Lindevald, Ian Morgan

    1987-09-01

    The perception of musical tones in a room is discussed in light of the room's chaotic sound transmission characteristics. We measure the auditory system's sensitivity to sound source level differences in a room for sine wave and harmonic tone signals. Using the method of adjustment, we derive just noticeable differences, 2.8 dB for the sine wave and 3.2 dB for the tone. The related difference limens derived using a forced choice methodology are 3.4 dB for the sine wave and 3.0, 3.1, and 2.8 dB for three varieties of a tone. The mutually agreeing JND and DL for the sine wave imply that the auditory system processes the equivalent of at least four samples of the room's statistical soundfield. The comparable discriminability of a harmonic tone, whose soundfield's std. dev. is already reduced due to its multiplicity of frequency samples, suggests that the value 3 dB can be considered a round number baseline criterion of discrimination in a room, independent of signal spectrum. Three routes by which the auditory system may access information about a sound source in a room are: (1) motion about the soundfield, (2) the room's onset transient and (3) binaurality. In a related loudness discrimination experiment, we find that with either of the first two of these routes, discrimination is nearly the same as with both; however, with neither, correct discrimination is by chance. We studied the third route by measuring the cross correlation of a random soundfield sampled at the two ears. Binaurality provides two independent sound samples at excitation frequencies above 500 Hz. This value represents a reduction of the two-microphone correlation frequency by a factor of two due to diffraction of sound by the head. With a masking (in a room) experiment, we find that the auditory system's ability to detect a sine wave in the presence of noise is improved by around 5 dB, when the masked tone is presented via the room's random transmission and the masker noise via earphones, as

  18. Popliteal Artery Entrapment Syndrome

    DEFF Research Database (Denmark)

    Altintas, Ümit; Helgstrand, Ulf Johan Vilhelm; Hansen, Marc A;

    2013-01-01

    The purpose of this study was to report our experience with popliteal artery entrapment syndrome (PAES) with special emphasis on the applicability of duplex ultrasound scanning (DUS) when diagnosing PAES. In addition to examining the correlation between DUS and intraoperative findings...

  19. Persistent Trigeminal Artery

    Directory of Open Access Journals (Sweden)

    Dijo T George

    2015-04-01

    Full Text Available Trigeminal artery is the commonest of the four primitive anastomoses between the carotid and vertebrobasilar system that may rarely persist in adults, with an angiographic incidence of 0.1 - 0.6%. We present the CT and MR angiograms of a patient who presented with a minor stroke and was detected to have this anomaly and briefly discuss the significance

  20. Functional Imaging of Human Vestibular Cortex Activity Elicited by Skull Tap and Auditory Tone Burst

    Science.gov (United States)

    Noohi, F.; Kinnaird, C.; Wood, S.; Bloomberg, J.; Mulavara, A.; Seidler, R.

    2016-01-01

    The current study characterizes brain activation in response to two modes of vestibular stimulation: skull tap and auditory tone burst. The auditory tone burst has been used in previous studies to elicit either the vestibulo-spinal reflex (saccular-mediated colic Vestibular Evoked Myogenic Potentials (cVEMP)), or the ocular muscle response (utricle-mediated ocular VEMP (oVEMP)). Some researchers have reported that air-conducted skull tap elicits both saccular and utricle-mediated VEMPs, while being faster and less irritating for the subjects. However, it is not clear whether the skull tap and auditory tone burst elicit the same pattern of cortical activity. Both forms of stimulation target the otolith response, which provides a measurement of vestibular function independent from semicircular canals. This is of high importance for studying otolith-specific deficits, including gait and balance problems that astronauts experience upon returning to earth. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation. Here we hypothesized that skull taps elicit similar patterns of cortical activity as the auditory tone bursts, and previous vestibular imaging studies. Subjects wore bilateral MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in the supine position, with eyes closed. Subjects received both forms of the stimulation in a counterbalanced fashion. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular system, resulting in the vestibular cortical response. Auditory tone bursts were also delivered for comparison. To validate our stimulation method, we measured the ocular VEMP outside of the scanner. This measurement showed that both skull tap and auditory

  1. Basilar Artery Aneurysm at a Persistent Trigeminal Artery Junction

    Science.gov (United States)

    Aguiar, G.B.; Conti, M.L.M.; Veiga, J.C.E.; Jory, M.; Souza, R.B.

    2011-01-01

    Summary The trigeminal artery is an anastomosis between the embryonic precursors of the vertebrobasilar and carotid systems, and may persist into adult life. The association of the persistent primitive trigeminal artery (PTA) with cerebral aneurysm is well documented in the literature and, in general, aneurysms are located in the anterior circulation. We describe a patient who presented with a panencephalic Fisher III subarachnoid hemorrhage due to rupture of an intracranial aneurysm. Digital arteriography showed a saccular aneurysm in the middle third of the basilar artery, adjacent to the junction with a persistent trigeminal artery. She was submitted to endovascular treatment with embolization of the basilar artery aneurysm with coils. Aneurysms at the PTA junction with the basilar artery are rare. This paper describes a case of PTA associated with an aneurysm in the basilar artery at PTA junction and briefly reviews the literature. PMID:22005697

  2. Investigation of piano soundboard voicing techniques and their impact on tone

    Science.gov (United States)

    Borland, Matt

    This thesis acts as a first step in connecting the subjective description of piano tone with quantitative measurements of changes in the vibrational and acoustical properties of a piano. Voicing techniques used by piano technicians are applied to a fully strung test piano and a series of tests are undertaken to measure the effect they have on piano tone. The addition of weights and riblets to a piano soundboard, two commonly practiced methods used to change the tone of a piano and even out the transition between the low tenor and high bass bridges, are examined in detail in this thesis. Modal analysis is the first test method applied and is used to determine the mode shapes and the modal properties of the test soundboard. The addition of small masses and riblets is shown to have the ability to change modal properties to varying degrees and connections are made between the output sound, attachment locations, modification locations, and mode shapes of the soundboard. A new technique, piano tone mapping, is introduced as a visualization method that displays the harmonic structure of the entire piano in one image. Using the technique creates a unique fingerprint of a piano that can be compared in various ways to other pianos. The piano tone maps reveal that initial magnitude and decay rate of the output sound are both decreased for notes with attachment points close to modification locations where weights and riblets are added. Impedance testing is also conducted for a number of different modifications. These tests reveal that riblets and weights each have their own frequency bands of influence, with the weights creating impedance changes primarily below 800 Hz and riblets creating impedance changes above 500 Hz, with a region of overlap between 500 Hz and 800 Hz. Tests also revealed that changes in impedance created by these voicing techniques were local in effect, with a region of influence less than 10 cm in radius extending from the location where the weight or

  3. Heme oxygenase-1 upregulation modulates tone and fibroelastic properties of internal anal sphincter.

    Science.gov (United States)

    Krishna, Chadalavada Vijay; Singh, Jagmohan; Kumar, Sumit; Rattan, Satish

    2014-09-15

    A compromise in the internal anal sphincter (IAS) tone and fibroelastic properties (FEP) plays an important role in rectoanal incontinence. Herein, we examined the effects of heme oxygenase (HO)-1 upregulation on these IAS characteristics in young rats. We determined the effect of HO-1 upregulator hemin on HO-1 mRNA and protein expressions and on basal IAS tone and its FEP before and after HO-1 inhibitor tin protoporphyrin IX. For FEP, we determined the kinetics of the IAS smooth muscle responses, by the velocities of relaxation, and recovery of the IAS tone following 0 Ca(2+) and electrical field stimulation. To characterize the underlying signal transduction for these changes, we determined the effects of hemin on RhoA-associated kinase (RhoA)/Rho kinase (ROCK) II, myosin-binding subunit of myosin light chain phosphatase 1, fibronectin, and elastin expression levels. Hemin increased HO-1 mRNA and protein similar to the increases in the basal tone, and in the FEP of the IAS. Underlying mechanisms in the IAS characteristics are associated with increases in the genetic and translational expressions of RhoA/ROCKII, and elastin. Fibronectin expression levels on the other hand were found to be decreased following HO-1 upregulation. The results of our study show that the hemin/HO-1 system regulates the tone and FEP of IAS. The hemin/HO-1 system thus provides a potential target for the development of new interventions aimed at treatment of gastrointestinal motility disorders, specifically the age-related IAS dysfunction.

  4. Étude des effets de la minimalisation des boues sur la méthanisation par digestion anaérobique

    OpenAIRE

    Amelem, Albert

    2012-01-01

    Le biogaz se présente comme une solution aux problèmes énergétiques actuels. La minimalisation des boues semble nous éloigner de notre objectif pour l’implantation d’un système de production d’énergie renouvelable. Les effets sur la méthanisation sont donc à étudier en profondeur. La modélisation et simulation des multiples procédés associés à la méthanisation par digestion anaérobique et la postérieur analyse financière ont permis de connaitre et comprendre l’effet de la minimalisation. Cett...

  5. Effet du travail du sol et des apports organiques sur l'érodibilité des sols des Rougiers de Camarès (Sud de la France)

    OpenAIRE

    Barthès, Bernard; Albrecht, Alain; Asseline, Jean; De Noni, Georges; Roose, Eric; Viennot, Marc

    1998-01-01

    Dans la petite région des Rougiers de Camarès, au sud du Massif Central, l'érosion hydrique provoque une dégradation des sols, en particulier sur les versants cultivés des collines, et une dégradation des infrastructures. L'objectif des travaux présentés est d'y évaluer l'effet du travail du sol et des apports organiques sur la sensibilité du sol à l'érosion, ou érodibilité. L'effet de cinq types de travail du sol (labour à plat conventionnel, labour à plat avec mulch, labour dressé, travail ...

  6. Etude des effets mitochondriaux du monoxyde d'azote :
    Régulation de l'oxydation phosphorylante et de la transition de perméabilité

    OpenAIRE

    Clerc, Pascaline

    2006-01-01

    Le monoxyde d'azote (NO) est formé à partir de L-arginine par la famille des NO synthases. La dysrégulation de la synthèse de cette molécule de signalisation cellulaire est impliquée dans le développement d'un grand nombre de pathologies. Les effets cellulaires du NO sont en partie dus à une inhibition des complexes de la chaîne respiratoire mitochondriale. Nous nous sommes intéressés aux effets du NO sur la régulation de l'oxydation phosphorylante et de le transition de perméabilité, deux pr...

  7. Effets de site : évalutation expérimentale et modélisations multidimensionnelles : application au site test EURO-SEISTEST (Grèce)

    OpenAIRE

    Riepl, Judith

    1997-01-01

    L'objectif de cette thèse est, l'étude fine des effets d'amplification suite à la géologie locale, notamment dans des bassins sédimentaires, ainsi que l'évaluation des avantages et Iimites des méthodes d'estimations. La partie expérimentale est basée sur des données acquises au site test EURO-SEISTEST, le premier site-test en Europe occidentale proche de Thessalonique (Grèce). Après une évaluation des effets d'amplification au site même et une étude de leur stabilité en fonction de plusieurs ...

  8. Effets d'apports organiques et de gypse sur la stabilité structurale de deux sols méditerranéens

    OpenAIRE

    Sidi, H.; Pansu, Marc

    1990-01-01

    Des expériences sur modèles de laboratoire ont été conduites avec des mélanges de matériaux terreux, de paille, de blé et de gypse. Une classification hiérarchique des échantillons selon leurs propriétés physico-chimiques montre l'effet des amendements organiques et gypseux sur les propriétés mesurées des sols, particulièrement leur stabilité structurale, en relation avec le temps d'incubation. L'article propose une approche de l'étude de la stabilité structurale des sols, sous l'effet d'amen...

  9. Selective increase of the contractile response to endothelin-1 in subcutaneous arteries from patients with essential hypertension

    DEFF Research Database (Denmark)

    Lind, H; Adner, M; Erlinge, D;

    1999-01-01

    arteries from subjects with established essential hypertension with matched controls. Furthermore, with RT-PCR, the occurrence of mRNA for the ETA and ET(B) receptors was shown in the tunica media layer of subcutaneous arteries in controls and hypertensives. The maximum contractile response to endothelin-1...... was significantly higher in the subcutaneous arteries of the hypertensives (by 88% with no change in potency) as compared to controls. The responses to noradrenaline, acetylcholine and potassium chloride did not differ between the groups. This selective increase in the contractile response to......Endothelin-1 has been shown to contribute to basal vascular tone in man. Since endothelin-1 is a potent vasoconstrictor putatively involved in hypertension, we have compared the contractile responses of endothelin-1 and noradrenaline in relation to potassium chloride in subcutaneous resistance...

  10. Composition of connective tissues and morphometry of vascular smooth muscle in arterial wall of DOCA-salt hypertensive rats - In relation with arterial remodeling.

    Science.gov (United States)

    Hayashi, Kozaburo; Shimizu, Emiko

    2016-05-01

    Hypertension (HT) was induced in Wistar rats aged 16 and 48 weeks by a deoxycortico-sterone acetate (DOCA)-salt procedure. Common carotid arteries were resected 16 weeks after, and their histological specimens were selectively stained for observations of collagen, elastin, and vascular smooth muscle (VSM) cells. Then, the fractions of collagen and elastin and their radial distributions, and the size and number of VSM cells were determined with an image analyzer. These results were compared with the results from age-matched, non-treated, normotensive (NT) animals and also with those from our previous biomechanical studies. In both age groups, there were no significant differences in the fractions of collagen and elastin, and the ratio of collagen to elastin content between HT and NT arteries. These results correspond well with our previous biomechanical results, which showed no significant difference in wall elasticity between HT and NT vessels. Moreover, in the innermost layer out of 4 layers bordered with thick elastic lamellae, the fraction of collagen was significantly greater in HT arteries than in NT ones, which is attributable to HT-related stress concentration in the layer. VSM cells were significantly hypertrophied and their content was increased by HT, although their total number in the media remained unchanged. The increased size and content of cells correspond to the enhancement of vascular tone and contractility in HT arteries.

  11. Composition of connective tissues and morphometry of vascular smooth muscle in arterial wall of DOCA-salt hypertensive rats - In relation with arterial remodeling.

    Science.gov (United States)

    Hayashi, Kozaburo; Shimizu, Emiko

    2016-05-01

    Hypertension (HT) was induced in Wistar rats aged 16 and 48 weeks by a deoxycortico-sterone acetate (DOCA)-salt procedure. Common carotid arteries were resected 16 weeks after, and their histological specimens were selectively stained for observations of collagen, elastin, and vascular smooth muscle (VSM) cells. Then, the fractions of collagen and elastin and their radial distributions, and the size and number of VSM cells were determined with an image analyzer. These results were compared with the results from age-matched, non-treated, normotensive (NT) animals and also with those from our previous biomechanical studies. In both age groups, there were no significant differences in the fractions of collagen and elastin, and the ratio of collagen to elastin content between HT and NT arteries. These results correspond well with our previous biomechanical results, which showed no significant difference in wall elasticity between HT and NT vessels. Moreover, in the innermost layer out of 4 layers bordered with thick elastic lamellae, the fraction of collagen was significantly greater in HT arteries than in NT ones, which is attributable to HT-related stress concentration in the layer. VSM cells were significantly hypertrophied and their content was increased by HT, although their total number in the media remained unchanged. The increased size and content of cells correspond to the enhancement of vascular tone and contractility in HT arteries. PMID:26987272

  12. Gestational pulmonary arterial hypertension

    OpenAIRE

    Moll, Matthew; Payne, Julie G.; Tukey, Melissa H.; Farber, Harrison W.

    2015-01-01

    Pulmonary arterial hypertension (PAH) is a progressive disease marked by the irreversible pulmonary vascular changes of vasoconstriction, thrombosis, and proliferation of smooth muscle and endothelial cells. The untreated clinical course is characterized by progressive dyspnea and a median survival of less than 3 years. Many of these patients are of child-bearing age; however, pregnancy leads to physiologic changes that are particularly poorly tolerated in PAH, conferring a 30%–56% mortality....

  13. CAROTID ARTERY DISEASE

    OpenAIRE

    Van Damme, H

    2009-01-01

    Carotid artery disease (CAD) become a commonly seen disease in general medical practice, due to the general population aging. Stroke, one of the most frequent complications of CAD and represents the third cause of death in Western countries. The leading cause of stroke in CAD is atheroembolism rather than flow-reduction. This paper reviewed imaging techniques, medical treatment and esepecially carotid endarterectomy (from point of view of indications, surgical technique and results) and caro...

  14. Myocardial arterial spin labeling

    OpenAIRE

    Kober, Frank; Jao, Terrence; Troalen, Thomas; Nayak, Krishna S.

    2016-01-01

    Arterial spin labeling (ASL) is a cardiovascular magnetic resonance (CMR) technique for mapping regional myocardial blood flow. It does not require any contrast agents, is compatible with stress testing, and can be performed repeatedly or even continuously. ASL-CMR has been performed with great success in small-animals, but sensitivity to date has been poor in large animals and humans and remains an active area of research. This review paper summarizes the development of ASL-CMR techniques, c...

  15. Neurobiology of hedonic tone: the relationship between treatment-resistant depression, attention-deficit hyperactivity disorder, and substance abuse

    Science.gov (United States)

    Sternat, Tia; Katzman, Martin A

    2016-01-01

    Anhedonia, defined as the state of reduced ability to experience feelings of pleasure, is one of the hallmarks of depression. Hedonic tone is the trait underlying one’s characteristic ability to feel pleasure. Low hedonic tone represents a reduced capacity to experience pleasure, thus increasing the likelihood of experiencing anhedonia. Low hedonic tone has been associated with several psychopathologies, including major depressive disorder (MDD), substance use, and attention-deficit hyperactivity disorder (ADHD). The main neural pathway that modulates emotional affect comprises the limbic–cortical–striatal–pallidal–thalamic circuits. The activity of various components of the limbic–cortical–striatal–pallidal–thalamic pathway is correlated with hedonic tone in healthy individuals and is altered in MDD. Dysfunction of these circuits has also been implicated in the relative ineffectiveness of selective serotonin reuptake inhibitors used to treat anxiety and depression in patients with low hedonic tone. Mood disorders such as MDD, ADHD, and substance abuse share low hedonic tone as well as altered activation of brain regions involved in reward processing and monoamine signaling as their features. Given the common features of these disorders, it is not surprising that they have high levels of comorbidities. The purpose of this article is to review the neurobiology of hedonic tone as it pertains to depression, ADHD, and the potential for substance abuse. We propose that, since low hedonic tone is a shared feature of MDD, ADHD, and substance abuse, evaluation of hedonic tone may become a diagnostic feature used to predict subtypes of MDD, such as treatment-resistant depression, as well as comorbidities of these disorders. PMID:27601909

  16. Neurobiology of hedonic tone: the relationship between treatment-resistant depression, attention-deficit hyperactivity disorder, and substance abuse.

    Science.gov (United States)

    Sternat, Tia; Katzman, Martin A

    2016-01-01

    Anhedonia, defined as the state of reduced ability to experience feelings of pleasure, is one of the hallmarks of depression. Hedonic tone is the trait underlying one's characteristic ability to feel pleasure. Low hedonic tone represents a reduced capacity to experience pleasure, thus increasing the likelihood of experiencing anhedonia. Low hedonic tone has been associated with several psychopathologies, including major depressive disorder (MDD), substance use, and attention-deficit hyperactivity disorder (ADHD). The main neural pathway that modulates emotional affect comprises the limbic-cortical-striatal-pallidal-thalamic circuits. The activity of various components of the limbic-cortical-striatal-pallidal-thalamic pathway is correlated with hedonic tone in healthy individuals and is altered in MDD. Dysfunction of these circuits has also been implicated in the relative ineffectiveness of selective serotonin reuptake inhibitors used to treat anxiety and depression in patients with low hedonic tone. Mood disorders such as MDD, ADHD, and substance abuse share low hedonic tone as well as altered activation of brain regions involved in reward processing and monoamine signaling as their features. Given the common features of these disorders, it is not surprising that they have high levels of comorbidities. The purpose of this article is to review the neurobiology of hedonic tone as it pertains to depression, ADHD, and the potential for substance abuse. We propose that, since low hedonic tone is a shared feature of MDD, ADHD, and substance abuse, evaluation of hedonic tone may become a diagnostic feature used to predict subtypes of MDD, such as treatment-resistant depression, as well as comorbidities of these disorders. PMID:27601909

  17. Case Report: Coronary arterial spasm in single right coronary artery

    Institute of Scientific and Technical Information of China (English)

    En-zhi JIA; Qi-jun SHAN; Zhi-jian YANG; Tie-bing ZHU; Lian-sheng WANG; Ke-jiang CAO; Wen-zhu MA

    2009-01-01

    We presented a case of anomalous single-coronary artery detected incidentally during routine coronary angiography. A 32-year-old male Chinese patient presented with recurrent pre-syncope and six episodes of syncope. Coronary angiography and coronary-computed tomography (CT)-angiography performed by a dual-source computed tomography (DSCT) revealed that the patient had a single large right coronary artery. A moderately large branch originated from the proximal part of the single right coronary artery and extended to the left, passing the anterior to the pulmonary artery, and divided into the anterior descending artery branch and circumflex branch at the base of the left auricular appendage. The episodes of the syncope were suspected to be caused by coronary arterial spasm, so this patient was on a regimen of 30 mg of diltiazem every 6 h and had no recurrence of syncope during follow-up.

  18. Effet de l'interaction coulombienne sur la localisation d'Anderson dans le gaz bidimensionnel d'électrons

    Science.gov (United States)

    Fleury, G.

    2010-09-01

    Nous étudions l’effet des interactions coulombiennes sur la localisation d’Anderson dans le gaz bidimensionnel d’électrons désordonné. L’objectif est de statuer sur la question de l’existence de métaux à deux dimensions. En l’absence d’interaction, la théorie d’échelle de la localisation prédit qu’un désordre infinitésimal suffit à localiser la fonction d’onde électronique et donc à rendre le système isolant à température nulle (Abrahams et al., 1979). Dans certaines limites extrêmes, les interactions peuvent être prises en compte et l’on aboutit également à un état isolant. Cependant, aucune théorie analytique ne permet de traiter le régime quantique non-perturbatif où désordre et interaction sont intermédiaires. Expérimentalement, il est possible de l’explorer dans des échantillons de haute mobilité et basse densité. Depuis 1994, des comportements métalliques inexpliqués y ont été observés (Kravchenko et al., 1994). Nous avons mis au point une méthode numérique permettant d’étudier le problème couplé de la localisation d’Anderson en présence d’interaction. Cette méthode mêle Monte Carlo quantique à température nulle et théorie d’échelle pour la conductance de Thouless. Nous trouvons que la théorie d’échelle de la localisation est préservée en présence d’interaction et donc que le gaz bidimensionnel, même corrélé, est isolant à température nulle. Nos résultats montrent de plus que les interactions délocalisent le gaz bidimensionnel et que cet effet de délocalisation est accru en présence de dégénérescence de vallées. Ils nous permettent de proposer un mécanisme simple rendant compte des principales caractéristiques des comportements métalliques observés expérimentalement.

  19. Effect of ionizing radiation on cardiovascular system; Les effets des rayonnements ionisants sur le systeme cardiovasculaire

    Energy Technology Data Exchange (ETDEWEB)

    Milliat, F.; Benderitter, M.; Gaugler, M.H. [Institut de radioprotection et de surete nucleaire, DRPH, SRBE, Laboratoire de radiopathologie et de therapies experimentales (LRTE), Fontenay-aux-Roses (France)

    2011-07-01

    Radiotherapy treatment for cancer of the chest, mediastinal area or the neck area is associated with increased risk of cardiovascular disease. With the increasing number of cancer patients and the increased treatment efficiency, the number of cancer survivors is increasing exponentially. The cancer survivors live longer and their long-term follow-up must be considered. The cardiovascular toxicity is mainly associated with the treatment of breast cancer, Hodgkin's lymphoma and head and neck cancer. Radiation-induced cardiovascular effects are insidious and chronic. Their occurrence is linked to numerous factors including the age of the patient at the beginning of the radiotherapy schedule, the number of years following radiotherapy, the doses (and volume) to the heart and the large vessels (coronary and carotid arteries), and the association with the traditional cardiovascular risk factors. Pathophysiological mechanisms remain unclear and, even if similarities with age-related atherosclerosis were established, the specificities of the radiation-induced atherosclerosis for high doses remain to be discovered. For low/moderate doses of ionising radiation, recent epidemiological studies provide evidence of increased risk of cardiovascular pathologies. A better knowledge of the mechanisms associated with the radiation-induced cardiovascular pathologies and the more precise identification of the populations at risk in the future should allow a more effective care of these patients with cardiovascular risk. (authors)

  20. Two-tone intensity-modulated optical stimulus for self-referencing microwave characterization of high-speed photodetectors

    Science.gov (United States)

    Wang, Heng; Zhang, Shangjian; Zou, Xinhai; Zhang, Yali; Lu, Rongguo; Zhang, Zhiyao; Zhang, Xiaoxia; Liu, Yong

    2016-08-01

    The two-tone intensity modulated optical stimulus is proposed and demonstrated for measuring the high-frequency response of photodetectors. The method provides a narrow linewidth and wide bandwidth optical stimulus based on the two-tone modulation of a Mach-Zehnder electro-optical intensity modulator, and achieves the self-referenced measurement of photodetectors without the need for correcting the power variation of optical stimulus. Moreover, the two-tone intensity modulation method allows bias-independent measurement with doubled measuring frequency range. In the experiment, the consistency between our method and the conventional methods verifies the simple but accurate measurement.

  1. Cortical pitch representations of complex tones in musicians and non-musicians

    DEFF Research Database (Denmark)

    Bianchi, Federica; Hjortkjær, Jens; Santurette, Sébastien;

    Musicians typically show enhanced pitch-discrimination ability compared to non-musicians, consistent with the fact that musicians are more sensitive to some acoustic features critical for both speech and music processing. However, it is still unclear which mechanisms underlie this perceptual...... enhancement. In a previous behavioral study, musicians showed an increased pitch-discrimination performance for both resolved and unresolved complex tones suggesting an enhanced neural representation of pitch at central stages of the auditory system. The aim of this study was to clarify whether musicians show...... (i) differential neural activation in response to complex tones as compared to non-musicians and/or (ii) finer fundamental frequency (F0) representation in the auditory cortex. Assuming that the right auditory cortex is specialized in processing fine spectral changes, we hypothesized that an enhanced...

  2. Complex-Tone Pitch Discrimination in Listeners With Sensorineural Hearing Loss

    DEFF Research Database (Denmark)

    Bianchi, Federica; Fereczkowski, Michal; Zaar, Johannes;

    2016-01-01

    Physiological studies have shown that noise-induced sensorineural hearing loss (SNHL) enhances the amplitude of envelope coding in auditory-nerve fibers. As pitch coding of unresolved complex tones is assumed to rely on temporal envelope coding mechanisms, this study investigated pitch......-discrimination performance in listeners with SNHL. Pitch-discrimination thresholds were obtained for 14 normal-hearing (NH) and 10 hearing-impaired (HI) listeners for sine-phase (SP) and random-phase (RP) complex tones. When all harmonics were unresolved, the HI listeners performed, on average, worse than NH listeners...... estimated in the same listeners. The estimated reduction of cochlear compression was significantly correlated with the increase in the F0DL ratio, while no correlation was found with filter bandwidth. The effects of degraded frequency selectivity and loss of compression were considered in a simplified...

  3. Effects of altered afferent articular input on sensation, proprioception, muscle tone and sympathetic reflex responses.

    Science.gov (United States)

    Slosberg, M

    1988-10-01

    The influence of afferent articular and periarticular input on muscle tone, joint mobility, proprioception and pain is of considerable interest to practitioners using manipulation. It has long been hypothesized that dysfunctional articulations may generate altered patterns of afferent input. This article reviews the relevant studies that have investigated the impact of articular input on efferent activity under normal conditions and under conditions of altered joint function. The findings suggest that sensory input does have a substantial effect on efferent function and sensation. Furthermore, the studies indicate that the pattern of articular input may be significantly modified by joint inflammation, trauma and effusion and result in changes of muscle tone, joint mobility, proprioception and pain. PMID:3069947

  4. Frequency-Zooming ARMA Modeling for Analysis of Noisy String Instrument Tones

    Directory of Open Access Journals (Sweden)

    Paulo A. A. Esquef

    2003-09-01

    Full Text Available This paper addresses model-based analysis of string instrument sounds. In particular, it reviews the application of autoregressive (AR modeling to sound analysis/synthesis purposes. Moreover, a frequency-zooming autoregressive moving average (FZ-ARMA modeling scheme is described. The performance of the FZ-ARMA method on modeling the modal behavior of isolated groups of resonance frequencies is evaluated for both synthetic and real string instrument tones immersed in background noise. We demonstrate that the FZ-ARMA modeling is a robust tool to estimate the decay time and frequency of partials of noisy tones. Finally, we discuss the use of the method in synthesis of string instrument sounds.

  5. Alterations in tone of voice in patients with restrictive anorexia nervosa: A pilot study

    Directory of Open Access Journals (Sweden)

    Concepción García-Santana

    2016-06-01

    Full Text Available This article is about the tone of voice (acoustic perception in patients with restrictive anorexia nervosa (AN-R. Our goal was to study whether or not there is an alteration of the tone in restrictive anorexia nervosa when the disease has started in the puberty. The total sample consisted of 148 subjects divided in two groups: control (n=102 and AN-R (n=46. The voice´s fundamental frequencies (F0 were determined based on the repetition of two phonemes ("a" and "i" and measured by a microphone Plantonic 300 and a digital recorder. We analyzed the voice´s F0 using Praat software. We present the first data for the normal range of the F0 in Spanish healthy women from 9 to 17 years old who were Spanish native speakers. Finally, we show a comparison of data between AN-R patients and control group.

  6. Multi-Band Multi-Tone Tunable Millimeter-Wave Frequency Synthesizer For Satellite Beacon Transmitter

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2016-01-01

    This paper presents the design and test results of a multi-band multi-tone tunable millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator. The intended application of the synthesizer is in a satellite beacon transmitter for radio wave propagation studies at K-band (18 to 26.5 GHz), Q-band (37 to 42 GHz), and E-band (71 to 76 GHz). In addition, the architecture for a compact beacon transmitter, which includes the multi-tone synthesizer, polarizer, horn antenna, and power/control electronics, has been investigated for a notional space-to-ground radio wave propagation experiment payload on a small satellite. The above studies would enable the design of robust high throughput multi-Gbps data rate future space-to-ground satellite communication links.

  7. A Novel Tone Mapping Based on Double-Anchoring Theory for Displaying HDR Images

    Science.gov (United States)

    Wang, Jinhua; Xu, De; Li, Bing

    In this paper, we present a Double-Anchoring Based Tone Mapping (DABTM) algorithm for displaying high dynamic range (HDR) images. First, two anchoring values are obtained using the double-anchoring theory. Second, we use the two values to formulate the compressing operator, which can achieve the aim of tone mapping directly. A new method based on accelerated K-means for the decomposition of HDR images into groups (frameworks) is proposed. Most importantly, a group of piecewise-overlap linear functions is put forward to define the belongingness of pixels to their locating frameworks. Experiments show that our algorithm is capable of achieving dynamic range compression, while preserving fine details and avoiding common artifacts such as gradient reversals, halos, or loss of local contrast.

  8. The Dissociation between Polarity, Semantic Orientation, and Emotional Tone as an Early Indicator of Cognitive Impairment

    Science.gov (United States)

    Arias Tapia, Susana A.; Martínez-Tomás, Rafael; Gómez, Héctor F.; Hernández del Salto, Víctor; Sánchez Guerrero, Javier; Mocha-Bonilla, J. A.; Barbosa Corbacho, José; Khan, Azizudin; Chicaiza Redin, Veronica

    2016-01-01

    The present study aims to identify early cognitive impairment through the efficient use of therapies that can improve the quality of daily life and prevent disease progress. We propose a methodology based on the hypothesis that the dissociation between oral semantic expression and the physical expressions, facial gestures, or emotions transmitted in a person's tone of voice is a possible indicator of cognitive impairment. Experiments were carried out with phrases, analyzing the semantics of the message, and the tone of the voice of patients through unstructured interviews in healthy people and patients at an early Alzheimer's stage. The results show that the dissociation in cognitive impairment was an effective indicator, arising from patterns of inconsistency between the analyzed elements. Although the results of our study are encouraging, we believe that further studies are necessary to confirm that this dissociation is a probable indicator of cognitive impairment. PMID:27683555

  9. Arterial stiffness as a risk factor for coronary artery disease.

    Science.gov (United States)

    Liao, Josh; Farmer, John

    2014-02-01

    Hypertension is a major modifiable risk factor, and clinical trials have demonstrated that successful reduction of elevated blood pressure to target levels translates into decreased risk for the development of coronary artery disease, stroke, heart failure, and renal failure. The arterial system had previously been regarded as a passive conduit for the transportation of arterial blood to peripheral tissues. The physiologic role the arterial system was greatly expanded by the recognition of the central role of the endothelial function in a variety of physiologic processes. The role of arterial function and structure in cardiovascular physiology was expanded with the development of a variety of parameters that evaluate arterial stiffness. Markers of arterial stiffness have been correlated with cardiovascular outcomes, and have been classified as an emerging risk factor that provides prognostic information beyond standard stratification strategies involving hypertension, diabetes, obesity, dyslipidemia and smoking. Multiple epidemiologic studies have correlated markers of arterial stiffness such as pulse-wave velocity, augmentation index and pulse pressure with risk for the development of fatal and nonfatal cardiovascular events. Additionally, measurements of arterial stiffness had clarified the results of clinical trials that demonstrated differing impacts on clinical outcomes, despite similar reductions in blood pressure, as measured by brachial and sphygmomanometry.

  10. A visibility matching tone reproduction operator for high dynamic range scenes

    Energy Technology Data Exchange (ETDEWEB)

    Larson, G.W. [Lawrence Berkeley National Lab., CA (United States); Rushmeier, H. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Piatko, C. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1997-01-15

    The authors present a tone reproduction operator that preserves visibility in high dynamic range scenes. The method introduces a new histogram adjustment technique, based on the population of local adaptation luminances in a scene. To match subjective viewing experience, the method incorporates models for human contrast sensitivity, glare, spatial acuity and color sensitivity. They compare the results to previous work and present examples the techniques applied to lighting simulation and electronic photography.

  11. Multi-Tone Millimeter-Wave Frequency Synthesizer for Atmospheric Propagation Studies

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2014-01-01

    The design and test results of a multi-tone millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator is presented. The intended applications of the synthesizer is in a space-borne transmitter for radio wave atmospheric studies at Q-band (37 to 43 GHz). These studies would enable the design of robust high data rate space-to-ground satellite communication links.

  12. Relating Pitch Awareness to Phonemic Awareness in Children: Implications for Tone-Deafness and Dyslexia

    OpenAIRE

    Loui, Psyche; Kroog, Kenneth; Zuk, Jennifer; Winner, Ellen; Schlaug, Gottfried

    2011-01-01

    Language and music are complex cognitive and neural functions that rely on awareness of one's own sound productions. Information on the awareness of vocal pitch, and its relation to phonemic awareness which is crucial for learning to read, will be important for understanding the relationship between tone-deafness and developmental language disorders such as dyslexia. Here we show that phonemic awareness skills are positively correlated with pitch perception–production skills in children. Chil...

  13. Relating Pitch Awareness to Phonemic Awareness in Children: Implications for Tone-Deafness and Dyslexia

    OpenAIRE

    Psyche eLoui; Kenneth eKroog; Jennifer eZuk; Ellen eWinner; Gottfried eSchlaug

    2011-01-01

    Language and music are complex cognitive and neural functions that rely on awareness of one’s own sound productions. Information on the awareness of vocal pitch, and its relation to phonemic awareness which is crucial for learning to read, will be important for understanding the relationship between tone-deafness and developmental language disorders such as dyslexia. Here we show that phonemic awareness skills are positively correlated with pitch perception-production skills in children. Chil...

  14. Auditory habituation to simple tones: reduced evidence for habituation in children compared to adults

    Directory of Open Access Journals (Sweden)

    Jana eMuenssinger

    2013-07-01

    Full Text Available Habituation – the response decrement to repetitively presented stimulation - is a basic cognitive capability and suited to investigate development and integrity of the human brain. To evaluate the developmental process of auditory habituation, the current study used magnetoencephalography to investigate auditory habituation, dishabituation and stimulus specificity in children and adults and compared the results between age groups. Twenty-nine children (Mage = 9.69 years, SD ± 0.47 and 14 adults (Mage = 29.29 years, SD ± 3.47 participated in the study and passively listened to a habituation paradigm consisting of 100 trains of tones which were composed of five 500Hz tones, one 750Hz tone (dishabituator and another two 500Hz tones, respectively while focusing their attention on a silent movie. Adults showed the expected habituation and stimulus specificity within-trains while no response decrement was found between trains. Sensory adaptation or fatigue as a source for response decrement in adults is unlikely due to the strong reaction to the dishabituator (stimulus specificity and strong mismatch negativity responses. However, in children neither habituation nor dishabituation or stimulus specificity could be found within-trains, response decrement was found across trains. It can be speculated that the differences between children and adults are linked to differences in stimulus processing due to attentional processes. This study shows developmental differences in task-related brain activation and discusses the possible influence of broader concepts such as attention, which should be taken into account when comparing performance in an identical task between age groups.

  15. Cortical activity associated with the detection of temporal gaps in tones: A magnetoencephalography study

    Directory of Open Access Journals (Sweden)

    Takako eMitsudo

    2014-10-01

    Full Text Available We used magnetoencephalography (MEG in two experiments to investigate spatio-temporal profiles of brain responses to gaps in tones. Stimuli consisted of leading and trailing markers with gaps between the two markers of 0, 30, or 80 ms. Leading and trailing markers were 300 ms pure tones at 800 Hz or 3200 Hz. Two conditions were examined: the within-frequency (WF condition in which the leading and trailing markers had identical frequencies, and the between-frequency (BF condition in which they had different frequencies. Using minimum-norm estimates (MNE, we localized the source activations at the time of the peak response to the trailing markers. Results showed that MEG signals in response to 800 Hz and 3200 Hz tones were localized in different regions within the auditory cortex, indicating that the frequency pathways activated by the two markers were spatially represented. The time course of regional activity (RA was extracted from each localized region for each condition. In Experiment 1, which used a continuous tone for the WF 0-ms stimulus, the N1m amplitude for the trailing marker in the WF condition differed depending on gap duration but not tonal frequency. In contrast, N1m amplitude in BF conditions differed depending on the frequency of the trailing marker. In Experiment 2, in which the 0-ms gap stimulus in the WF condition was made from two markers and included an amplitude reduction in the middle, the amplitude in WF and BF conditions changed depending on frequency, but not gap duration. The difference in temporal characteristics between WF and BF conditions could be observed in the regional activity.

  16. Estimation of cochlear response times using lateralization of frequency-mismatched tones

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Dau, Torsten

    2009-01-01

    Behavioral and objective estimates of cochlear response times CRTs and traveling-wave TW velocity were compared for three normal-hearing listeners. Differences between frequency-specific CRTs were estimated via lateralization of pulsed tones that were interaurally mismatched in frequency, similar...... could not be estimated with the behavioral method due to limitations of the lateralization paradigm. The method might be useful for studying the spatiotemporal cochlear response pattern in human listeners....

  17. KV7 channels regulate muscle tone and nonadrenergic noncholinergic relaxation of the rat gastric fundus

    OpenAIRE

    Ipavec, V.; Martire, M; Barrese, V.; Taglialatela, M; Currò, D.

    2011-01-01

    Voltage-dependent type 7 K+ (KV7) channels play important physiological roles in neurons and muscle cells. The aims of the present study were to investigate the motor effects of KV7 channel modulators in the rat gastric fundus and the expression of KV7 channels in this tissue. Muscle tone and electrical field stimulation (EFS)-evoked relaxations of precontracted longitudinal muscle strips of the rat gastric fundus were investigated under nonadrenergic noncholinergic conditions by organ bath s...

  18. Effects of superoxide generating systems on muscle tone, cholinergic and NANC responses in cat airway.

    Science.gov (United States)

    Bauer, V; Nakajima, T; Pucovsky, V; Onoue, H; Ito, Y

    2000-02-14

    To study the possible role of reactive oxygen species in airway hyperreactivity, we examined the effects of the superoxide anion radical (O(2)(-)) generating systems, pyrogallol and xanthine with xanthine oxidase, on muscle tone, excitatory and inhibitory neurotransmission in the cat airway. Smooth muscle contraction or non-adrenergic non-cholinergic (NANC) relaxation evoked by electrical field stimulation (EFS) were measured before or after O(2)(-) generating systems with or without diethydithiocarbamic acid (DEDTCA), an inhibitor of endogenous superoxide dismutase (SOD). Resting membrane potential or excitatory junction potential (EJP) were also measured in vitro. Both pyrogallol and xanthine/xanthine oxidase produced biphasic changes in basal and elevated (by 5-HT) muscle tone. After SOD pretreatment, both systems consistently produced a prolonged contraction, thereby indicating that O(2)(-) was converted to H(2)O(2) by the action of SOD and as a result the actions of O(2)(-) were lost but those of H(2)O(2) introduced. The O(2)(-) showed no significant effect on smooth muscle contraction or EJP evoked by EFS, however after DEDTCA pretreatment, it evoked initial enhancement followed by suppression of the contraction and EJP. DEDTCA pretreatment ameliorated the inhibitory action of pyrogallol and xanthine/xanthine oxidase on the NANC relaxation, probably because O(2)(-) could combine with endogenous NO to form peroxynitrite. These results indicate that the O(2)(-) generating systems have multiple actions, presumably due to the presence and simultaneous action of at least two different reactive oxygen species (O(2)(-) and H(2)O(2)). While H(2)O(2) seems to be responsible for elevation of muscle tone and augmentation of smooth muscle contraction by EFS, O(2)(-) inhibits muscle tone, cholinergic and NANC neurotransmission.

  19. SmarTone-Vodafone 手机版YouTube大玩现金回馈

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    一向鬼点子众多的SmarTone-Vodafone最近又有新招,他们专门为青少年设置了Wap网站“Teen地带”内容包括MV、铃声、full track、游戏、浏览、优惠券等,而且还有“随身IM”(类似MSN)。

  20. White Matter Changes Associated with Resting Sympathetic Tone in Frontotemporal Dementia vs. Alzheimer's Disease.

    Directory of Open Access Journals (Sweden)

    Mario F Mendez

    Full Text Available Resting sympathetic tone, a measure of physiological arousal, is decreased in patients with apathy and inertia, such as those with behavioral variant frontotemporal dementia (bvFTD and other frontally-predominant disorders.To identify the neuroanatomical correlates of skin conductance levels (SCLs, an index of resting sympathetic tone and apathy, among patients with bvFTD, where SCLs is decreased, compared to those with Alzheimer's disease (AD, where it is not.This study analyzed bvFTD (n = 14 patients and a comparison group with early-onset AD (n = 19. We compared their resting SCLs with gray matter and white matter regions of interest and white matter measures of fiber integrity on magnetic resonance imaging and diffusion tensor imaging.As expected, bvFTD patients, compared to AD patients, had lower SCLs, which correlated with an apathy measure, and more gray matter loss and abnormalities of fiber integrity (fractional anisotropy and mean diffusivity in frontal-anterior temporal regions. After controlling for group membership, the SCLs were significantly correlated with white matter volumes in the cingulum and inferior parietal region in the right hemisphere.Among dementia patients, SCLs, and resting sympathetic tone, may correlate with quantity of white matter, rather than with gray matter or with white matter fiber integrity. Loss of white matter volumes, especially involving a right frontoparietal network, may reflect chronic loss of cortical axons that mediate frontal control of resting sympathetic tone, changes that could contribute to the apathy and inertia of bvFTD and related disorders.

  1. Cyclostationary Model Based Multiple-Tone Interference Rejection in DSSS Communication Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Multiple-tone interference is a kind of narrow band interference appears in Direct Sequence (DS) Spread Spectrum (SS) communication system frequently that degrades the system performance. Most open literature studies on narrowband interference rejection assumed stationary SS signal and interference. SS signal and interference are modeled as cyclostationary and based on cyclostationary model, an interference rejection algorithm is proposed. Through computer simulation, it is shown that the performance of the SS system can be improved considerably after adopting this algorithm.

  2. Oxide nanoparticle EUV resists: toward understanding the mechanism of positive and negative tone patterning

    KAUST Repository

    Chakrabarty, Souvik

    2013-04-01

    DUV, EUV and e-beam patterning of hybrid nanoparticle photoresists have been reported previously by Ober and coworkers. The present work explores the underlying mechanism that is responsible for the dual tone patterning capability of these photoresist materials. Spectroscopic results correlated with mass loss and dissolution studies suggest a ligand exchange mechanism responsible for altering the solubility between the exposed and unexposed regions. © 2013 SPIE.

  3. True aneurysm of brachial artery.

    Science.gov (United States)

    Hudorović, Narcis; Lovričević, Ivo; Franjić, Dario Bjorn; Brkić, Petar; Tomas, Davor

    2010-10-01

    True upper extremity peripheral artery aneurysms are a rarely encountered arterial disorder. Following computer-tomography angiographic (CT-a) imaging examination, true saccular aneurysm, originating from the left brachial artery was diagnosed in the 77-year-old female without history of trauma. The aneurysm was resected by surgical intervention, and primary repair of the brachial artery was performed by interposition of a part of great saphenous vein harvested from the left groin and creation of two end-to-end anastomoses between interposition graft and previously resected part of brachial artery. No complication was observed during the follow-up. Surgical intervention for upper extremity aneurysms should be initiated without delay. Factors combined with minimal morbidity associated with repair suggest that surgical repair should be performed routinely for true upper extremity arterial aneurysms. PMID:20865459

  4. Arterial responses during migraine headache

    DEFF Research Database (Denmark)

    Iversen, Helle Klingenberg; Nielsen, T H; Olesen, J;

    1990-01-01

    The superficial temporal artery has been thought to be the main focus of pain during migraine attacks, but its diameter has never been measured directly. The use of a new, high-resolution ultrasound machine to measure arterial size in 25 migraine patients with unilateral head pain showed...... that the lumen was wider on the painful than on the non-painful side during a migraine attack. The diameters of both radial arteries and the temporal artery on the non-painful side were smaller during than between attacks. The generalised vasoconstriction was not shared by the temporal artery on the affected...... side, which suggests a local vasodilatory response. The findings suggest that cephalic arteries may play a role in migraine pathogenesis....

  5. Large endolymphatic potentials from low-frequency and infrasonic tones in the guinea pig.

    Science.gov (United States)

    Salt, Alec N; Lichtenhan, Jeffery T; Gill, Ruth M; Hartsock, Jared J

    2013-03-01

    Responses of the ear to low-frequency and infrasonic sounds have not been extensively studied. Understanding how the ear responds to low frequencies is increasingly important as environmental infrasounds are becoming more pervasive from sources such as wind turbines. This study shows endolymphatic potentials in the third cochlear turn from acoustic infrasound (5 Hz) are larger than from tones in the audible range (e.g., 50 and 500 Hz), in some cases with peak-to-peak amplitude greater than 20 mV. These large potentials were suppressed by higher-frequency tones and were rapidly abolished by perilymphatic injection of KCl at the cochlear apex, demonstrating their third-turn origins. Endolymphatic iso-potentials from 5 to 500 Hz were enhanced relative to perilymphatic potentials as frequency was lowered. Probe and infrasonic bias tones were used to study the origin of the enhanced potentials. Potentials were best explained as a saturating response summed with a sinusoidal voltage (Vo), that was phase delayed by an average of 60° relative to the biasing effects of the infrasound. Vo is thought to arise indirectly from hair cell activity, such as from strial potential changes caused by sustained current changes through the hair cells in each half cycle of the infrasound. PMID:23464026

  6. TONE AT THE TOP’: FIGHTING MILITARY CORRUPTION IN LATIN AMERICA

    Directory of Open Access Journals (Sweden)

    Liliane Klaus

    2015-11-01

    Full Text Available This essay aims to discuss how tone at the top works in the traditional military contexts found in Latin America, and how the right tone could be adopted in corrupt military institutions to move towards an ethical role-modelling environment. For this endeavour, several strategies that can help military generals to fight military unethical culture in contaminated hierarchical organisations will be proposed, while a number of hypotheses on the institution’s functioning will be provided. Differently from private companies’ theoretical bias, the main suggested approach implies the initial establishment of a strong, transactional-based tone at the top as the main tool to fight military corruption. As a further step, after the corrupt culture has been neutralised, transactional leadership based on ethics could be slowly transformed into gentler versions of transformational style, but never letting the main fear of the harshest punishment evanesce. In summary, by showing that unethical leadership will necessarily pave the way for misconduct in traditional military organisations, we propose a cannonball strategy, based on a punishment and reward system, to reinforce integrity instead of gentler or charismatic leadership styles.

  7. Compensation for pitch-shifted auditory feedback during the production of Mandarin tone sequences

    Science.gov (United States)

    Xu, Yi; Larson, Charles R.; Bauer, Jay J.; Hain, Timothy C.

    2004-08-01

    Recent research has found that while speaking, subjects react to perturbations in pitch of voice auditory feedback by changing their voice fundamental frequency (F0) to compensate for the perceived pitch-shift. The long response latencies (150-200 ms) suggest they may be too slow to assist in on-line control of the local pitch contour patterns associated with lexical tones on a syllable-to-syllable basis. In the present study, we introduced pitch-shifted auditory feedback to native speakers of Mandarin Chinese while they produced disyllabic sequences /ma ma/ with different tonal combinations at a natural speaking rate. Voice F0 response latencies (100-150 ms) to the pitch perturbations were shorter than syllable durations reported elsewhere. Response magnitudes increased from 50 cents during static tone to 85 cents during dynamic tone productions. Response latencies and peak times decreased in phrases involving a dynamic change in F0. The larger response magnitudes and shorter latency and peak times in tasks requiring accurate, dynamic control of F0, indicate this automatic system for regulation of voice F0 may be task-dependent. These findings suggest that auditory feedback may be used to help regulate voice F0 during production of bi-tonal Mandarin phrases.

  8. The perception of Cantonese lexical tones by early-deafened cochlear implantees

    Science.gov (United States)

    Ciocca, Valter; Francis, Alexander L.; Aisha, Rani; Wong, Lena

    2002-05-01

    This study investigated whether cochlear implant users can identify Cantonese lexical tones, which differ primarily in their F0 pattern. Seventeen early-deafened deaf children (age=4 years, 6 months to 8 years, 11 months; postoperative period=11-41 months) took part in the study. Sixteen children were fitted with the Nucleus 24 cochlear implant system; one child was fitted with a Nucleus 22 implant. Participants completed a 2AFC picture identification task in which they identified one of the six contrastive Cantonese tones produced on the monosyllabic target word /ji/. Each target stimulus represented a concrete object and was presented within a carrier phrase in sentence-medial position. Group performance was significantly above chance for three contrasts. However, the cochlear implant listeners performed much worse than a 612-year-old, moderately hearing impaired control listener who was tested on the same task. These findings suggest that this group of cochlear implant users had great difficulty in extracting the pitch information needed to accurately identify Cantonese lexical tones.

  9. The role of phonological alternation in speech production: evidence from Mandarin tone sandhi.

    Science.gov (United States)

    Politzer-Ahles, Stephen; Zhang, Jie

    2014-05-01

    We investigate the role of phonological alternation during speech production in Mandarin using implicit priming, a paradigm in which participants respond faster to words in sets that are phonologically homogeneous than in sets that are phonologically heterogeneous. We test whether priming is obtained when words in a set share the same tones at the underlying level but have different tones at the surface level-i.e., when the set includes a word that undergoes a phonological alternation which changes the tone. Sets that are heterogeneous at the surface level (in which the heterogeneity is due to a phonological operation) failed to elicit priming, as did sets that are heterogeneous at the underlying and surface levels (in which the heterogeneity is due to the lexical representations). This finding suggests that the phonological alternation was computed before the initiation of articulation, offering evidence that the progression from underlying phonological representations to articulatory execution may be mediated online by phonological input-to-output mapping. Furthermore, sets of words that are heterogeneous only at the surface level showed a different trend than sets of words that are heterogeneous at both levels, suggesting that both the surface and underlying levels of representation play a role during speech production.

  10. Relating Pitch Awareness to Phonemic Awareness in Children: Implications for Tone-Deafness and Dyslexia

    Directory of Open Access Journals (Sweden)

    Psyche eLoui

    2011-05-01

    Full Text Available Language and music are complex cognitive and neural functions that rely on awareness of one’s own sound productions. Information on the awareness of vocal pitch, and its relation to phonemic awareness which is crucial for learning to read, will be important for understanding the relationship between tone-deafness and developmental language disorders such as dyslexia. Here we show that phonemic awareness skills are positively correlated with pitch perception-production skills in children. Children between the ages of 7 and 9 were tested on pitch perception and production, phonemic awareness, and IQ. Results showed a significant positive correlation between pitch perception-production and phonemic awareness, suggesting that the relationship between musical and linguistic sound processing is intimately linked to awareness at the level of pitch and phonemes. Since tone-deafness is a pitch-related impairment and dyslexia is a deficit of phonemic awareness, we suggest that dyslexia and tone-deafness may have a shared and/or common neural basis.

  11. Challenges for immersion lithography extension based on negative tone imaging (NTI) process

    Science.gov (United States)

    Shirakawa, Michihiro; Omatsu, Tadashi; Ou, Keiyu; Yonekuta, Yasunori; Hatakeyama, Naoya; Asakawa, Daisuke; Yakushiji, Takashi; Fujita, Mitsuhiro; Muraki, Nanae

    2016-03-01

    Negative tone imaging (NTI) process is a method for obtaining a negative-tone reversal pattern by developing with an organic solvent. As NTI process can break-through the resolution limit of a conventional positive tone development (PTD) process at specific pattern such as trenches and contact holes, it have been applied for a mass production in 20nm and 14nm nodes devices. In NTI system, because a developer is changed from a hydrophilic aqueous solution to a hydrophobic organic solvent, it is possible to review the common resist stack which is optimized for a PTD process. In this paper, we examined the possibility of a bi-layer process using a Si-containing NTI resist. Etching selectivity between the Si-NTI resist and a SOC improved by raising Si-content of the Si-NTI resist, but resolution deteriorates as a trade-off. By suppressing swelling behavior of the Si-NTI resist with a polymer structure control, we overcame this trade-off. As a result, in sub-90 nm pitch L/S and CH patterns, the resolution of the Si-NTI resist achieved comparable level to a conventional NTI resist. In addition, SOC etching was successfully carried out by using the Si-NTI resist pattern as an etching hard mask.

  12. Relating pitch awareness to phonemic awareness in children: implications for tone-deafness and dyslexia.

    Science.gov (United States)

    Loui, Psyche; Kroog, Kenneth; Zuk, Jennifer; Winner, Ellen; Schlaug, Gottfried

    2011-01-01

    Language and music are complex cognitive and neural functions that rely on awareness of one's own sound productions. Information on the awareness of vocal pitch, and its relation to phonemic awareness which is crucial for learning to read, will be important for understanding the relationship between tone-deafness and developmental language disorders such as dyslexia. Here we show that phonemic awareness skills are positively correlated with pitch perception-production skills in children. Children between the ages of seven and nine were tested on pitch perception and production, phonemic awareness, and IQ. Results showed a significant positive correlation between pitch perception-production and phonemic awareness, suggesting that the relationship between musical and linguistic sound processing is intimately linked to awareness at the level of pitch and phonemes. Since tone-deafness is a pitch-related impairment and dyslexia is a deficit of phonemic awareness, we suggest that dyslexia and tone-deafness may have a shared and/or common neural basis. PMID:21687467

  13. Stimulus presentation order and the perception of lexical tones in Cantonese

    Science.gov (United States)

    Francis, Alexander L.; Ciocca, Valter

    2003-09-01

    Listeners' auditory discrimination of vowel sounds depends in part on the order in which stimuli are presented. Such presentation order effects have been argued to be language independent, and to result from psychophysical (not speech- or language-specific) factors such as the decay of memory traces over time or increased weighting of later-occurring stimuli. In the present study, native Cantonese speakers' discrimination of a linguistic tone continuum is shown to exhibit order of presentation effects similar to those shown for vowels in previous studies. When presented with two successive syllables differing in fundamental frequency by approximately 4 Hz, listeners were significantly more sensitive to this difference when the first syllable was higher in frequency than the second. However, American English-speaking listeners with no experience listening to Cantonese showed no such contrast effect when tested in the same manner using the same stimuli. Neither English nor Cantonese listeners showed any order of presentation effects in the discrimination of a nonspeech continuum in which tokens had the same fundamental frequencies as the Cantonese speech tokens but had a qualitatively non-speech-like timbre. These results suggest that tone presentation order effects, unlike vowel effects, may be language specific, possibly resulting from the need to compensate for utterance-related pitch declination when evaluating fundamental frequency for tone identification.

  14. The effect of mastication muscular tone on facial size in patients with Down syndrome

    Directory of Open Access Journals (Sweden)

    Margaretha Suharsini

    2006-12-01

    Full Text Available Muscular hypotonia is one of the clinical signs in patients with Down syndrome. As a characteristic of patients with Down syndrome, hypotonia is clearly evident in face expression and oral dysfunction. Dentocraniofacial growth abnormalities in patients with Down syndrome may be influenced by genetic and environmental factors. Stomatognathic system musculature as an environmental factor (factor outside the bone can affect dentocraniofacial growth by orofacial muscles activities when chewing, swallowing, breathing, and speaking. Oral dysfunctions commonly seen in patients with Down syndrome are open mouth, protruding tongue posture, difficulties when chewing, swallowing, and speaking, drooling, and mouth breathing. The purpose of this study was to observe how the mastication muscular tone affecting the facial size of Down syndrome patient. Twenty five of 14–18 years old children with Down syndrome were diagnosed by clinical characteristic and cytogenetic examination. Mastication muscular tone was described by masseter and temporalis muscle synergy and oral function, whereas the facial size consisted of facial size of lateral, anteroposterior and vertical growth. The result of regression test revealed that the degree of mastication muscular tone has a significant effect on facial size of the anteroposterior growth and facial size of vertical growth, but did not significantly influence the facial size of lateral growth.

  15. PRELIMINARY STUDY OF THREE-TONE PARADIGM AUDITORY P300 ON AGING DEMENTIA

    Institute of Scientific and Technical Information of China (English)

    张晓君; 赵毅; 高玉红; 耿稚萍; 余华峰

    2001-01-01

    Objective. To explore the changes of three-tone paradigm P300 and observe the improvement of the diagnostic sensitivity of P300 in aging dementia. Methods. Thirty-four patients of aging dementia underwent traditional P300 (2t-P300) and three-tone paradigm auditory P300 (3t-P300). The results of these two methods were compared. Results. Abnormal P300 was found in 18 of 34 dementia cases (52. 9% ) by 2t-P300, and in 26 of 30 pa-tients who finished the 3t-P300 tests (86. 7% ). In 2t-P300, 9 of 24 mild cases, 7 of 8 moderate cases and 2 severe cases showed abnormal results. In 3t-P300, 20 of 24 mild cases and all 6 moderate cases showed abnormal results. Abnormal 3t-P300 was found in 13 of 16 cases which showed normal 2t-P300. Besides prolonged and bad-shaped P300, no certain response of P300 to rare non-target stimulus (r-nT) was found in 10 mild cases by 3t-P300. Conclusion. Three-tone paradigm auditory P300 had higher sensitivity in early diagnosis of aging dementia than traditional auditory P300. No P300 response to r-nT in 3t-P300 is an important index in early diagnosis of mild dementia.

  16. PRELIMINARY STUDY OF THREE-TONE PARADIGM AUDITORY P300 ON AGING DEMENTIA

    Institute of Scientific and Technical Information of China (English)

    张晓君; 赵毅; 高玉红; 耿稚萍; 余华峰

    2001-01-01

    Objective. To explore the changes of three-tone paradigm P300 and observe the improvement of the diagnostic sensitivity of P300 in aging dementia.``Methods. Thirty-four patients of aging dementia underwent traditional P300 (2t-P300) and three-tone paradigm auditory P300 (3t-P300). The resuhs of these two methods were compared.Results. Abnormal P300 was found in 18 of 34 dementia cases (52.9%) by 2t-P300, and in 26 of 30 patients who finished the 3t-P300 tests (86. 7% ). In 2t-P300, 9 of 24 mild cases, 7 of 8 moderate cases and 2severe cases showed abnormal results. In 3t-P300, 20 of 24 mild cases and all 6 moderate cases showed abnormal results. Abnormal 3t-P300 was found in 13 of 16 cases which showed normal 2t-P300. Besides prolonged and bad-shaped P300, no certain response of P300 to rare non-target stimulus (r-nT) was found in 10 mild cases by 3t-P300.``Conclusion. Three-tone paradigm auditory P300 had higher sensitivity in early diagnosis of aging dementia than traditional auditory P300. No P300 response to r-nT in 3t-P300 is an important index in early diagnosis of mild dementia.

  17. Efficacy of three-tone disclosing agent as an adjunct in caries risk assessment

    Directory of Open Access Journals (Sweden)

    Mungara Jayanthi

    2015-01-01

    Full Text Available Background: Today, most approaches to caries viewed that catastrophic change in normal plaque biofilm is responsible for the disease. The behavior and composition of the biofilm are a reflection of the oral environment; the caries is a reflection of adverse changes occurring in that environment. Thus, it is important to identify the pathogenicity of the plaque biofilm so as to predict the caries risk. The recently developed three-tone plaque disclosing agent was used to test its ability in identifying the pathogenicity of plaque. Aim: To assess the efficacy of three-tone plaque disclosing agent in identifying the plaque pathogenicity and correlate with the clinical caries status and microbiological findings. Materials and Methods: Sixty children of 6-13 years age group of both sexes were clinically examined for caries and plaque scores, and then disclosing agent was applied; the color stained plaque samples were collected and cultured for microbiological assessment, and the data were analyzed based on the caries status of the children. Results: There was a significant difference between the pathological plaque of caries active and caries free group (P < 0.05. The pathological plaque scores and the total colony counts, Streptococcus counts and mutans streptococci counts increased with the increase in caries. Conclusion: Three-tone plaque disclosing agent was effective in identifying pathological plaque and can be used as one of the chairside adjuvants in caries risk assessment.

  18. Developmental changes in mismatch responses to mandarin consonants and lexical tones from early to middle childhood.

    Directory of Open Access Journals (Sweden)

    Huei-Mei Liu

    Full Text Available The purpose of this study was to use mismatch responses (MMRs to explore the dynamic changes of Mandarin speech perception abilities from early to middle childhood. Twenty preschoolers, 18 school-aged children, and 26 adults participated in this study. Two sets of synthesized speech stimuli varying in Mandarin consonant (alveolo-palatal affricate vs. fricative and lexical tone features (rising vs. contour tone were used to examine the developmental course of speech perception abilities. The results indicated that only the adult group demonstrated typical early mismatch negativity (MMN responses, suggesting that the ability to discriminate specific speech cues in Mandarin consonant and lexical tone is a continuing process in preschool- and school-aged children. Additionally, distinct MMR patterns provided evidence indicating diverse developmental courses to different speech characteristics. By incorporating data from the two speech conditions, we propose using MMR profiles consisting of mismatch negativity (MMN, positive mismatch response (p-MMR, and late discriminative negativity (LDN as possible brain indices to investigate speech perception development.

  19. Tone-mapping and dynamic range compression using dynamic cone response

    Science.gov (United States)

    Yun, Byoung-Ju; Hong, Hee-Dong; Park, Jinhyoung; Kim, Hyun-Deok; Choi, Ho-Hyoung

    2013-11-01

    Over the last several decades, the tone-mapping and color correction methods have been incorporated into the display device such as LCD/LED display device or the photographic print. However, conventional methods are based on Gray-World Assumption using spatial smoothing filter to estimate the local illumination component. For this reason, most of these methods have several problems like visual perception problem, scale the contrast, gray-out, color distortion (dominate color, halo-artifact) and so on. Accordingly, this paper presents a color correction method using the dynamic cone response function based on human visual perception. The proposed method consists of tone-mapping and dynamic cone response. The tone-mapped image is obtained by using chromatic and achromatic colors. Thereafter, the resultant image is processed through the dynamic cone response function, and it is to estimate the dynamic response of human eye as well as to deal with mismatch between a real scene and the rendered image. The experimental results show that the proposed method yields better performance of color correction over the conventional methods.

  20. Les effets musculaires de la vitamine D : application à la perte musculaire liée à l’âge

    Directory of Open Access Journals (Sweden)

    Walrand Stéphane

    2014-05-01

    Full Text Available Au-delà de ses rôles biologiques classiques sur la santé osseuse, les effets extra-squelettiques de la vitamine D font actuellement l’objet de nombreuses recherches. La présence du récepteur de la vitamine D dans la plupart des tissus de l’organisme vient d’ailleurs renforcer l’argument en faveur de ses fonctions multiples. Parmi celles-ci, l’effet de la vitamine D sur la masse et les performances musculaires a été longtemps pressenti. En effet, dans la Grèce Antique, Hérodote recommandait le soleil comme un remède pour les « muscles faibles et mous », et les anciens Olympiens recevaient l’ordre de se coucher exposés aux rayons du soleil pour améliorer leurs performances physiques. En 1952, Spellerberg, un physiologiste du sport, a réalisé une vaste étude portant sur les effets de l’irradiation UV sur les performances d’athlètes de haut niveau. Suite aux résultats positifs de cette investigation, ce scientifique dû informer le Comité Olympique que l’irradiation UV présentait un effet « convaincant » sur la performance physique et les capacités motrices. Ces données sont conformes à de nombreuses études postérieures signalant une amélioration des aptitudes physiques, de la vitesse et de l’endurance chez des sujets jeunes traités par des UV ou par des suppléments contenant de la vitamine D. Des observations complémentaires font état d’un effet significatif sur la force musculaire, en particulier au niveau des membres inférieurs. Concernant les mécanismes mis en jeu, certaines études fondamentales récentes ont montré que la vitamine D exerce des effets moléculaires au sein de la cellule musculaire. Précisément, une action régulatrice de la vitamine D sur les flux de calcium, l’homéostasie minérale et certaines voies de signalisation contrôlant l’anabolisme protéique a été rapportée au niveau du tissu musculaire. Plusieurs enquêtes épidémiologiques révèlent qu

  1. Hystérésis et réduction de sons auto-entretenus commandées par effet Coanda

    Science.gov (United States)

    Guérin, Sébastien; Allery, Cyrille; Sakout, Anas

    An air flow crossing two baffles in tandem inside a duct, generates strong self-sustained tones. Four radial slots created on the upstream baffle, leads to a large hysteresis loop of the sound pressure level when velocity varies, the second branch of which corresponds with a reduction of the self-sustained tones. Measurements of velocity show that a Coanda effect happens on the jets issued from the slots, which induces this flow behaviour.

  2. The right hepatic artery syndrome

    Institute of Scientific and Technical Information of China (English)

    Kazumi Miyashita; Katsuya Shiraki; Takeshi Ito; Hiroki Taoka; Takeshi Nakano

    2005-01-01

    Various benign and malignant conditions could cause biliary obstruction. Compression of extrahepatic bile duct (EBD) by right hepatic artery was reported as a right hepatic artery syndrome but all cases were compressed EBD from stomach side. Our case compressed from dorsum was not yet reported, so it was thought to be a very rare case. We present here the first case of bile duct obstruction due to the compression of EBD from dorsum by right hepatic artery.

  3. Eléments d'analyse du cliquetis et de ses effets Elements for Analyzing Knocking and Its Effects

    Directory of Open Access Journals (Sweden)

    Douaud A.

    2006-11-01

    Full Text Available On présente dans cet article une synthèse des travaux théoriques et expérimentaux relatifs à la génération du cliquetis et à ses effets sur le fonctionnement du moteur. L'apparition du cliquetis est décrite par un mécanisme global de délai d'auto-inflammation. Des exemples d'application portant sur l'identification du délai de carburants quelconques et sur l'optimisation de l'ensemble moteurs-carburants documentent cette approche. Le cliquetis a pour conséquence un accroissement de sollicitations mécaniques et thermiques des parois de la chambre de combustion. Des méthodes et résultats d'investigation de ces phénomènes sont présentés. A synthesis is presented of theoretical and experimental research concerning the generating of knocking and its effects on engine running. The appearance of knocking is described by an overall mechanism of autoignition delay. This approach is documented by applied examples concerning the identification of the delay involved with any type of fuel and the optimizing of engine-fuel systems. Knocking causes an increase in mechanical and thermal stresses on combustion-chamber walls. Investigational methods and results concerning these phenomena are described.

  4. Integrative modeling of small artery structure and function uncovers critical parameters for diameter regulation.

    Directory of Open Access Journals (Sweden)

    Ed VanBavel

    Full Text Available Organ perfusion is regulated by vasoactivity and structural adaptation of small arteries and arterioles. These resistance vessels are sensitive to pressure, flow and a range of vasoactive stimuli. Several strongly interacting control loops exist. As an example, the myogenic response to a change of pressure influences the endothelial shear stress, thereby altering the contribution of shear-dependent dilation to the vascular tone. In addition, acute responses change the stimulus for structural adaptation and vice versa. Such control loops are able to maintain resistance vessels in a functional and stable state, characterized by regulated wall stress, shear stress, matched active and passive biomechanics and presence of vascular reserve. In this modeling study, four adaptation processes are identified that together with biomechanical properties effectuate such integrated regulation: control of tone, smooth muscle cell length adaptation, eutrophic matrix rearrangement and trophic responses. Their combined action maintains arteries in their optimal state, ready to cope with new challenges, allowing continuous long-term vasoregulation. The exclusion of any of these processes results in a poorly regulated state and in some cases instability of vascular structure.

  5. Arterial mapping of lower limbs

    International Nuclear Information System (INIS)

    A bibliographic review is realized in the arterial mapping of lower limbs by ultrasonographic. The physical properties of the Doppler effect applied to diagnostic ultrasound are described. The anatomical characteristics of the general arterial system and specifically of the lower limbs arterial system are mentioned. Pathologies of the ischemic arterial disease of lower limbs are explained. The study characteristics of lower limbs arterial mapping are documented to determine its importance as appropriate method for the assessment of lower limb ischemia. An adequate arterial mapping of lower limbs is recognized in atherosclerotic ischemic disease as a reliable initial method alternative to arteriography. Arteriography is considered as reference pattern for therapeutic decision making in patients with critical ischemia of the lower limbs. Non-invasive methods to assess the arterial system of lower limbs has evidenced the advantages of the arterial mapping with Doppler, according to the consulted literature. The combination morphological and hemodynamic information has been possible and a map of the explored zone is made. The arterial mapping by ultrasonography has offered similar reliability to angiography

  6. Exhaustive swimming differentially inhibits P2X1 receptor- and α1-adrenoceptor-mediated vasoconstriction in isolated rat arteries

    Institute of Scientific and Technical Information of China (English)

    Lu LI; Tao WU; Cong WEI; Jian-ke HAN; Zhen-hua JIA; Yi-ling WU; Lei-ming REN

    2012-01-01

    Aim:To investigate the effects of exhaustive swimming exercise on P2X1 receptor- and α1-adrenoceptor-mediated vasoconstriction of different types of arteries in rats.Methods:Male Wistar rats were divided into 2 groups:the sedentary control group (SCG) and the exhaustive swimming exercise group (ESEG).The rats in the ESEG were subjected to a swim to exhaustion once a day for 2 weeks.Internal carotid,caudal,pulmonary,mesenteric arteries and aorta were dissected out.Isometric vasoconstrictive responses of the arteries to α,β-methylene ATP (α,β-MeATP) or noradrenaline (NA) were recorded using a polygraph.Results:The exhaustive swimming exercise did not produce significant change in the EC5o values of α,β-MeATP or NA in vasoconstrictive response of most of the arteries studied.The exhaustive swimming exercise inhibited the vasoconstrictive responses to P2X1 receptor activation in the internal carotid artery,whereas it reduced the maximal vasoconstrictive responses to α1-adrenoceptor stimulation in the caudal,pulmonary,mesenteric arteries and aorta.The rank order of the reduction of the maximal vasoconstriction was as follows:mesenteric,pulmonary,caudal,aorta.Conclusion:Exhaustive swimming exercise differentially affects the P2X1 receptor- and α1-adrenoceptor-regulated vasoconstriction in internal carotid artery and peripheral arteries.The ability to preserve purinergic vasoconstriction in the peripheral arteries would be useful to help in maintenance of the basal vascular tone during exhaustive swimming exercise.

  7. High- and Low-Frequency Probe Tone Tympanometry in Chinese Infants

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To assess the utility of low- and high-frequency tympanometry in the diagnosis of middle ear dysfunction in Chinese infants. Methods Tympanograms were obtained with 226 Hz, 678 Hz and 1000 Hz probe tones from infants aged 5-25 weeks with normal auditory brainstem responses (ABRs)(15 infants,30 ears) and withprolonged wave Ⅰ latencies(17 infants, 20 ears), suggesting middle ear dysfunction, using a GSI Tympstar middle ear analyzer Version Ⅱ. Results The single-peaked tympanogram was the most characteristic type in both groups and seen in 25 ears (83.3%) in the normal ABR group and in 18 ears (90%) in the delayed wave Ⅰ group, respectively. The peak pressure, peak compensated static acoustic admittance and gradient of 226 Hz tympanometry were of no significant differences between the two groups. The 678 Hz tympanograms of admittance, susceptance and conductance demonstrated non-peak, single-, double- and tri-peaked patterns in both groups. The agreement between ABRs and 678 Hz tympanograms of admittance,susceptance and conductance were 70.0%, 58.0% and 64.0%(kappa=0.324, 0.234 and 0.118) respectively. For 1000 Hz probe tone, admittance,susceptance and conductance tympanograms showed single peaked patterns in 28 (93.3%), 25 (83.3%) and 26 (86.7%) of the 30 normal ears. Admittance, susceptance and conductance tympanograms using the 1000 Hz probe tone were flat in 15 (75%), 17(85%) and 13 (65%) of the ears in infants with prolonged wave Ⅰ latencies. For 1000 Hz admittance, susceptance and conductance Tympanograms, the agreement between tympanometry and ABR results were 90.0%, 92.0% and 86.0% with kappa at 0.783, 0.831 and 0.690, respectively. Conclusion 1000 Hz probe tone tympanometry is a promising middle ear function test for infants of 1-6 months age, while 226 Hz and 678 Hz probe tones are less efficient in detecting middle ear dysfunction in infants.

  8. [The single coronary artery].

    Science.gov (United States)

    Godart, F; Berzin, B; Rihani, R; Pecheux, M; Dutoit, A

    1992-04-01

    Single coronary artery is a fairly rare entity which may nevertheless be found in 0.4 per cent of coronary arteriograms. The authors report 3 cases seen in 2 departments of cardiology. In each patient, despite the existence of definite cardiovascular risk factors, this distribution was a factor worsening coronary ischemia, leading to complete thrombosis in one case. Although most often a chance discovery, a review of the literature justifies the attribution to this anomaly of the onset of angina, infarction or even sudden death. PMID:1642437

  9. Patent arterial duct

    OpenAIRE

    Martin Robin P; Elmasry Ola A; Forsey Jonathan T

    2009-01-01

    Abstract Patent arterial duct (PAD) is a congenital heart abnormality defined as persistent patency in term infants older than three months. Isolated PAD is found in around 1 in 2000 full term infants. A higher prevalence is found in preterm infants, especially those with low birth weight. The female to male ratio is 2:1. Most patients are asymptomatic when the duct is small. With a moderate-to-large duct, a characteristic continuous heart murmur (loudest in the left upper chest or infraclavi...

  10. Resting Vagal Tone and Vagal Response to Stress: Associations with Anxiety, Aggression and Perceived Anxiety Control among Youth

    OpenAIRE

    Scott, Brandon G.; Weems, Carl F.

    2014-01-01

    This study tested the associations of both resting vagal tone and vagal response to stress with anxiety control beliefs, anxiety, and aggression among 80 youth (aged 11-17 years). Measures included physiological assessments of emotion regulation along with youth self-report of anxiety control beliefs, anxiety, and aggression and caregiver reports of their child's anxiety and aggression. Resting vagal tone was positively related to anxiety control beliefs, but negatively associated with anxiet...

  11. THE PRACTICALITY OF USING THE TASK-BASED INSTRUCTION——IMPROVING STUDENTS'UNDERSTANDING OF STRESS AND TONE

    Institute of Scientific and Technical Information of China (English)

    顾敏

    2008-01-01

    This study investigated the efficacy of the Task-based instruction for improving students' understanding and awareness of stress and tone.23 learners made up the control group to receive the traditional method as opposed to 23 learners who receive the task-based instruction to teach stress and tone. The results indicated statistically significant differences between the Control and Experimental groups on the variables of post test scores.

  12. Nonadrenergic, noncholinergic responses stabilize smooth muscle tone, with and without parasympathetic activation, in guinea-pig isolated airways.

    Science.gov (United States)

    Lindén, A; Löfdahl, C G; Ullman, A; Skoogh, B E

    1993-03-01

    In guinea-pig isolated airways, nonadrenergic, noncholinergic (NANC) neural responses converge towards a similar level of smooth muscle tone, via a contraction when the tone is low prior to stimulation, and via a relaxation when the tone is high prior to stimulation. We wanted to assess the effect of simultaneous parasympathetic activation on these converging NANC responses, with and without the addition of sympathetic activation. In guinea-pig isolated airways, the spontaneous airway tone was initially abolished by indomethacin (10 microM). In one series, adrenergic depletion by guanethidine (10 microM) was then established, with and without cholinergic blockade by atropine (1 microM). In another series, either cholinergic blockade by atropine (1 microM) or no blockade was utilized. Responses to electrical field stimulation (1,200 mA, 0.5 ms, 3 Hz for 240 s) were studied with no induced tone, at a moderate (0.3 microM) and at a near-maximum (6 microM), histamine-induced tone. The mean level of the tonus equilibrium (% of maximum tone) was higher with the simultaneous NANC and parasympathetic activation than with NANC activation alone (75% compared with 44%, in the main bronchus, n = 8). The level of the tonus equilibrium was also higher with the simultaneous NANC, sympathetic and parasympathetic activation than with NANC and sympathetic activation only (49% compared with 21%, in the main bronchus, n = 8). The pattern was similar in the distal trachea. In conclusion, NANC neural responses can stabilize smooth muscle tone, and this stabilizing effect can be modulated by both parasympathetic and sympathetic activation, in guinea-pig isolated airways. PMID:8472834

  13. Active and passive characteristics of muscle tone and their relationship to models of subluxation/joint dysfunction: Part I

    OpenAIRE

    Knutson, Gary A; Owens, Edward F

    2003-01-01

    The relationship of muscles to the causes and effects of the pathophysiologic entity referred to as chiropractic subluxation or joint dysfunction is critical. Part I of this paper reviews complexities of skeletal muscle in regards to anatomy, active and passive tone, detection of muscle tone, neurophysiology, and how muscle function fits into a variety of subluxation/joint dysfunction models. The review culminates in Part II with a hypothesis to describe and explain varying degrees of muscle ...

  14. Studying the Difference in the Effect of Noise and Pure Tone on the Residual Inhibition in Patients Suffering Tinnitus

    OpenAIRE

    Majid Norouzi; Abdollah Mousavi; Masoumeh Rouzbehani

    1998-01-01

    Objectives: we were aimed at studying the difference in the effect of noise and pure tone on the residual inhibition in patients suffering tinnitus. "nMethod: patients were selected among whom referred to audiology clinic in Ran faculty of rehabilitation sciences and aged between 20-70 years old. Our method in studying patients was experimental- masking with pure tone was performed in patients who had experienced partial residual inhibition with noise. Results; the differences between the mas...

  15. Association between internal carotid artery dissection and arterial tortuosity

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca; Piga, Mario [Azienda Ospedaliero Universitaria (A.O.U.), Department of Radiology, Monserrato, Cagliari (Italy); Argiolas, Giovanni Maria; Siotto, Paolo [Azienda Ospedaliero Brotzu (A.O.B.), Department of Radiology, di Cagliari (Italy); Sumer, Suna; Wintermark, Max [Neuroradiology Division, Neuroradiology, UVA Department of Radiology, Charlottesville, VA (United States); Raz, Eytan [New York University School of Medicine, Department of Radiology, New York, NY (United States); Sapienza University of Rome, Department of Neurology and Psychiatry, Rome (Italy); Sanfilippo, Roberto; Montisci, Roberto [Azienda Ospedaliero Universitaria (A.O.U.), Department of Vascular Surgery, di Cagliari (Italy)

    2014-10-18

    Carotid artery dissection is an important cause of ischemic stroke in all age groups, particularly in young patients. The purpose of this work was to assess whether there is an association between the presence of an internal carotid artery dissection (ICAD) and the arterial tortuosity. This study considered 124 patients (72 males and 52 females; median age 57 years) with CT/MR diagnosis of ICAD of the internal carotid artery were considered in this multi-centric retrospective study. The arterial tortuosity was evaluated and, when present, was categorized as elongation, kinking, or coiling. For each patient, both the right and left sides were considered for a total number of 248 arteries in order to have the same number of cases and controls. Fisher's exact test was applied to test the association between elongation, kinking, coiling, dissection, and the side affected by CAD. Fisher's exact test showed a statistically significant association between the ICAD and kinking (p = 0.0089) and coiling (p = 0.0251) whereas no statistically significant difference was found with arterial vessel elongation (p = 0.444). ICAD was more often seen on the left side compared to the right (p = 0.0001). These results were confirmed using both carotid arteries of the same patient as dependent parameter with p = 0.0012, 0.0129, and 0.3323 for kinking, coiling, and elongation, respectively. The presence of kinking and coiling is associated with ICAD. (orig.)

  16. Dual anterior descending coronary artery associated with coronary artery disease

    Directory of Open Access Journals (Sweden)

    Siqueira Luciane da L. V.

    2003-01-01

    Full Text Available The patient is a male with risk factors for coronary artery disease, who was referred for cardiac catheterization after acute myocardial infarction in the inferior wall. The patient underwent transluminal coronary angioplasty in the right coronary artery with successful stent implantation.

  17. Bilateral Internal Thoracic Artery Configuration for Coronary Artery Bypass Surgery

    Science.gov (United States)

    Boodhwani, Munir; Hanet, Claude; de Kerchove, Laurent; Navarra, Emiliano; Astarci, Parla; Noirhomme, Philippe; El Khoury, Gebrine

    2016-01-01

    Background— Bilateral internal thoracic arteries (BITA) have demonstrated superior patency and improved survival in patients undergoing coronary artery bypass grafting. However, the optimal configuration for BITA utilization and its effect on long-term outcome remains uncertain. Methods and Results— We randomly assigned 304 patients undergoing coronary artery bypass grafting using BITA to either in situ or Y grafting configurations. The primary end point was 3-year angiographic patency. Secondary end points included major adverse cardiac and cerebrovascular events (ie, death from any cause, stroke, myocardial infarction, or repeat revascularization) at 7 years. More coronary targets were able to be revascularized using internal thoracic arteries in patients randomized to Y grafting versus in situ group (3.2±0.8 versus 2.4±0.5 arteries/patient; PURL: http://www.clinicaltrials.gov. Unique identifier: NCT01666366. PMID:27406988

  18. True arterial system compliance estimated from apparent arterial compliance.

    Science.gov (United States)

    Quick, C M; Berger, D S; Hettrick, D A; Noordergraaf, A

    2000-03-01

    A new method has been developed to estimate total arterial compliance from measured input pressure and flow. In contrast to other methods, this method does not rely on fitting the elements of a lumped model to measured data. Instead, it relies on measured input impedance and peripheral resistance to calculate the relationship of arterial blood volume to input pressure. Generally, this transfer function is a complex function of frequency and is called the apparent arterial compliance. At very low frequencies, the confounding effect of pulse wave reflection disappears, and apparent compliance becomes total arterial compliance. This study reveals that frequency components of pressure and flow below heart rate are generally necessary to obtain a valid estimate of compliance. Thus, the ubiquitous practice of estimating total arterial compliance from a single cardiac cycle is suspect under most circumstances, since a single cardiac cycle does not contain these frequencies. PMID:10784093

  19. Individual differences in processing pitch contour and rise time in adults: A behavioral and electrophysiological study of Cantonese tone merging.

    Science.gov (United States)

    Ou, Jinghua; Law, Sam-Po

    2016-06-01

    One way to understand the relationship between speech perception and production is to examine cases where the two dissociate. This study investigates the hypothesis that perceptual acuity reflected in event-related potentials (ERPs) to rise time of sound amplitude envelope and pitch contour [reflected in the mismatch negativity (MMN)] may associate with individual differences in production among speakers with otherwise comparable perceptual abilities. To test this hypothesis, advantage was taken of an on-going sound change-tone merging in Cantonese, and compared the ERPs between two groups of typically developed native speakers who could discriminate the high rising and low rising tones with equivalent accuracy but differed in the distinctiveness of their production of these tones. Using a passive oddball paradigm, early positive-going EEG components to rise time and MMN to pitch contour were elicited during perception of the two tones. Significant group differences were found in neural responses to rise time rather than pitch contour. More importantly, individual differences in efficiency of tone discrimination in response latency and magnitude of neural responses to rise time were correlated with acoustic measures of F0 offset and rise time differences in productions of the two rising tones.

  20. Computer-aided assessment of tone production: A case of Zimbabwean students learning Chinese as a foreign language

    Directory of Open Access Journals (Sweden)

    Herbert Mushangwe

    2014-01-01

    Full Text Available This study examined how technology can help in assessing and teaching Chinese tones to foreign students who are not used to tonal languages. It was an attempt to show how we can use the PRAAT software to make learners of Chinese as a foreign language realize their tonal errors. The data used was collected from the students at the University of Zimbabwe studying Chinese and this was part of a continuous assessment for the students’ pronunciation of Chinese tones. This method which was used by teachers to assess students’ tones was found to be easy to follow such that students could also utilize it for their own pronunciation practice. We argued that the use of computer-aided assessment makes assessment of students’ tone acquisition lesser arbitrary than when the teacher merely gives comments based on his or her individual perception. This is because this assessment method gives PRAAT acoustic pictures which show the tone structures for each student; hence, both the student and the teacher can visualize the errors. Since PRAAT can provide a platform to compare the student’s pronunciation with that of the native speaker and at the same time can help the teacher to explain why student’s pronunciation is wrong, this paper concludes that PRAAT can be a useful tool in assessing and teaching Chinese tones.

  1. Human umbilical cord expresses several vasoactive peptides involved in the local regulation of vascular tone: protein and gene expression of Orphanin, Oxytocin, ANP, eNOS and iNOS

    Directory of Open Access Journals (Sweden)

    Aldo Gerbino

    2011-07-01

    Full Text Available Full-term human umbilical cord contains three blood vessels: two arteries coiled around a vein and surrounded by Wharton’s jelly, a mucous tissue with few mesenchymal stromal cells and abundant extracellular matrix. Umbilical vessels lack innervations, thus endothelial cells must play a role in the control of blood flow. The aim of this study was to investigate in human umbilical cord the expression of five peptides that could be involved in the regulation of vascular tone: Orphanin FQ, Oxytocin, Atrial Natriuretic Peptide (ANP, endothelial Nitric Oxide Synthase (eNOS and inducible Nitric Oxide Synthase (iNOS. The expression of these molecules in full-term human umbilical cord was investigated through immunohistochemistry and RT-PCR. Immunoreactivity for Orphanin FQ was detected in Wharton’s jelly, vessel musculature and endothelium; Oxytocin, ANP and eNOS were expressed by the umbilical epithelium, Wharton’s jelly and endothelium, whereas iNOS only by endothelial cells. RT-PCR analysis showed transcriptional expression of Oxytocin, ANP and eNOS mRNAs. The presence of Orphanin, Oxytocin, ANP, eNOS and iNOS proteins was identified in the human umbilical cord. mRNA expression for Oxytocin, ANP and eNOS suggest that these molecules are synthesized by umbilical cord cells themselves. The expression of these vasoactive molecules could be part of a general mechanism locally regulating vascular tone. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 2, pp. 211–218

  2. Genetics Home Reference: pulmonary arterial hypertension

    Science.gov (United States)

    ... Home Health Conditions pulmonary arterial hypertension pulmonary arterial hypertension Enable Javascript to view the expand/collapse boxes. ... All Open All Close All Description Pulmonary arterial hypertension is a progressive disorder characterized by abnormally high ...

  3. H2S induces vasoconstriction of rat cerebral arteries via cAMP/adenylyl cyclase pathway.

    Science.gov (United States)

    Li, Sen; Ping, Na-Na; Cao, Lei; Mi, Yan-Ni; Cao, Yong-Xiao

    2015-12-15

    Hydrogen sulfide (H2S), traditionally known for its toxic effects, is now involved in regulating vascular tone. Here we investigated the vasoconstrictive effect of H2S on cerebral artery and the underlying mechanism. Sodium hydrosulfide (NaHS), a donor of H2S, concentration-dependently induced vasoconstriction on basilar artery, which was enhanced in the presence of isoprenaline, a β-adrenoceptor agonist or forskolin, an adenylyl cyclase activator. Administration of NaHS attenuated the vasorelaxant effects of isoprenaline or forskolin. Meanwhile, the NaHS-induced vasoconstriction was diminished in the presence of 8B-cAMP, an analog of cAMP, but was not affected by Bay K-8644, a selective L-type Ca(2+) channel agonist. These results could be explained by the revised effects of NaHS on isoprenaline-induced cAMP elevation and forskolin-stimulated adenylyl cyclase activity. Additionally, NaHS-induced vasoconstriction was enhanced by removing the endothelium or in the presence of L-NAME, an inhibitor of nitric oxide synthase. L-NAME only partially attenuated the effect of NaHS which was given together with forskolin on the pre-contracted artery. In conclusion, H2S induces vasoconstriction of cerebral artery via, at least in part, cAMP/adenylyl cyclase pathway.

  4. Endothelium-derived Relaxing Factors of Small Resistance Arteries in Hypertension.

    Science.gov (United States)

    Kang, Kyu-Tae

    2014-09-01

    Endothelium-derived relaxing factors (EDRFs), including nitric oxide (NO), prostacyclin (PGI2), and endothelium-derived hyperpolarizing factor (EDHF), play pivotal roles in regulating vascular tone. Reduced EDRFs cause impaired endothelium-dependent vasorelaxation, or endothelial dysfunction. Impaired endothelium-dependent vasorelaxation in response to acetylcholine (ACh) is consistently observed in conduit vessels in human patients and experimental animal models of hypertension. Because small resistance arteries are known to produce more than one type of EDRF, the mechanism(s) mediating endothelium-dependent vasorelaxation in small resistance arteries may be different from that observed in conduit vessels under hypertensive conditions, where vasorelaxation is mainly dependent on NO. EDHF has been described as one of the principal mediators of endothelium-dependent vasorelaxation in small resistance arteries in normotensive animals. Furthermore, EDHF appears to become the predominant endothelium-dependent vasorelaxation pathway when the endothelial NO synthase (NOS3)/NO pathway is absent, as in NOS3-knockout mice, whereas some studies have shown that the EDHF pathway is dysfunctional in experimental models of hypertension. This article reviews our current knowledge regarding EDRFs in small arteries under normotensive and hypertensive conditions. PMID:25343007

  5. Epigenetics and Peripheral Artery Disease.

    Science.gov (United States)

    Golledge, Jonathan; Biros, Erik; Bingley, John; Iyer, Vikram; Krishna, Smriti M

    2016-04-01

    The term epigenetics is usually used to describe inheritable changes in gene function which do not involve changes in the DNA sequence. These typically include non-coding RNAs, DNA methylation and histone modifications. Smoking and older age are recognised risk factors for peripheral artery diseases, such as occlusive lower limb artery disease and abdominal aortic aneurysm, and have been implicated in promoting epigenetic changes. This brief review describes studies that have associated epigenetic factors with peripheral artery diseases and investigations which have examined the effect of epigenetic modifications on the outcome of peripheral artery diseases in mouse models. Investigations have largely focused on microRNAs and have identified a number of circulating microRNAs associated with human peripheral artery diseases. Upregulating or antagonising a number of microRNAs has also been reported to limit aortic aneurysm development and hind limb ischemia in mouse models. The importance of DNA methylation and histone modifications in peripheral artery disease has been relatively little studied. Whether circulating microRNAs can be used to assist identification of patients with peripheral artery diseases and be modified in order to improve the outcome of peripheral artery disease will require further investigation.

  6. Pulmonary arterial hypertension : an update

    NARCIS (Netherlands)

    Hoendermis, E. S.

    2011-01-01

    Pulmonary arterial hypertension (PAH), defined as group 1 of the World Heart Organisation (WHO) classification of pulmonary hypertension, is an uncommon disorder of the pulmonary vascular system. It is characterised by an increased pulmonary artery pressure, increased pulmonary vascular resistance a

  7. Liver cirrhosis and arterial hypertension

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Møller, Søren

    2006-01-01

    Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems (renin-angiotensin-aldosterone system, sympathetic nervous system, release...... blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development...... of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most...

  8. Thai lexical tone perception in native speakers of Thai, English and Mandarin Chinese: An event-related potentials training study

    Directory of Open Access Journals (Sweden)

    Bao Mingzhen

    2008-06-01

    Full Text Available Abstract Background Tone languages such as Thai and Mandarin Chinese use differences in fundamental frequency (F0, pitch to distinguish lexical meaning. Previous behavioral studies have shown that native speakers of a non-tone language have difficulty discriminating among tone contrasts and are sensitive to different F0 dimensions than speakers of a tone language. The aim of the present ERP study was to investigate the effect of language background and training on the non-attentive processing of lexical tones. EEG was recorded from 12 adult native speakers of Mandarin Chinese, 12 native speakers of American English, and 11 Thai speakers while they were watching a movie and were presented with multiple tokens of low-falling, mid-level and high-rising Thai lexical tones. High-rising or low-falling tokens were presented as deviants among mid-level standard tokens, and vice versa. EEG data and data from a behavioral discrimination task were collected before and after a two-day perceptual categorization training task. Results Behavioral discrimination improved after training in both the Chinese and the English groups. Low-falling tone deviants versus standards elicited a mismatch negativity (MMN in all language groups. Before, but not after training, the English speakers showed a larger MMN compared to the Chinese, even though English speakers performed worst in the behavioral tasks. The MMN was followed by a late negativity, which became smaller with improved discrimination. The High-rising deviants versus standards elicited a late negativity, which was left-lateralized only in the English and Chinese groups. Conclusion Results showed that native speakers of English, Chinese and Thai recruited largely similar mechanisms when non-attentively processing Thai lexical tones. However, native Thai speakers differed from the Chinese and English speakers with respect to the processing of late F0 contour differences (high-rising versus mid-level tones. In

  9. Fatal dissection of the pulmonary artery in pulmonary arterial hypertension

    Directory of Open Access Journals (Sweden)

    B. Degano

    2009-09-01

    Full Text Available A 41-yr-old patient with chronic stable idiopathic pulmonary arterial hypertension (PAH presented with sudden chest pain and unusual dyspnoea during physical exertion. The patient had been diagnosed with PAH at the age of 12 yrs and was in New York Heart Association functional class I/II. The patient was being treated with an anticoagulant regimen, low-dose diuretics and continuous intravenous epoprostenol therapy. A computed tomography scan showed ancient massive thrombi in dilated central pulmonary arteries, which were not haemodynamically significant (perfusion lung scans did not demonstrate segmental or larger defects, and extensive dissection of the right pulmonary artery starting from the intermediate branch. Due to the extensiveness of the dissection, the patient was immediately considered for heart–lung transplantation, but died 72 h after the onset of symptoms. Permission for post mortem examination was denied. Pulmonary artery dissection should be suspected in PAH patients presenting with chest pain and worsening dyspnoea. In the current case, the factors possibly associated with increased risk for dissection may include dilatation of the pulmonary artery, local inflammation favoured by in situ thrombosis, and acute increase of pulmonary pressure secondary to physical exertion. Extensive pulmonary artery dissection is a life-threatening complication of PAH, and urgent heart/lung transplantation might be the treatment of choice in eligible patients. In addition, better identification of the risk factors for pulmonary artery dissection may help in considering transplantation for selected patients at risk.

  10. Patent arterial duct

    Directory of Open Access Journals (Sweden)

    Martin Robin P

    2009-07-01

    Full Text Available Abstract Patent arterial duct (PAD is a congenital heart abnormality defined as persistent patency in term infants older than three months. Isolated PAD is found in around 1 in 2000 full term infants. A higher prevalence is found in preterm infants, especially those with low birth weight. The female to male ratio is 2:1. Most patients are asymptomatic when the duct is small. With a moderate-to-large duct, a characteristic continuous heart murmur (loudest in the left upper chest or infraclavicular area is typical. The precordium may be hyperactive and peripheral pulses are bounding with a wide pulse pressure. Tachycardia, exertional dyspnoea, laboured breathing, fatigue or poor growth are common. Large shunts may lead to failure to thrive, recurrent infection of the upper respiratory tract and congestive heart failure. In the majority of cases of PAD there is no identifiable cause. Persistence of the duct is associated with chromosomal aberrations, asphyxia at birth, birth at high altitude and congenital rubella. Occasional cases are associated with specific genetic defects (trisomy 21 and 18, and the Rubinstein-Taybi and CHARGE syndromes. Familial occurrence of PAD is uncommon and the usual mechanism of inheritance is considered to be polygenic with a recurrence risk of 3%. Rare families with isolated PAD have been described in which the mode of inheritance appears to be dominant or recessive. Familial incidence of PAD has also been linked to Char syndrome, familial thoracic aortic aneurysm/dissection associated with patent arterial duct, and familial patent arterial duct and bicuspid aortic valve associated with hand abnormalities. Diagnosis is based on clinical examination and confirmed with transthoracic echocardiography. Assessment of ductal blood flow can be made using colour flow mapping and pulsed wave Doppler. Antenatal diagnosis is not possible, as PAD is a normal structure during antenatal life. Conditions with signs and symptoms of

  11. Effect of beta-adrenergic blockade on elevated arterial compliance and low systemic vascular resistance in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Bendtsen, Flemming; Henriksen, Jens Henrik

    2001-01-01

    ) of 17.8 mmHg, and responded to beta-blocker treatment with a significant reduction in the HVPG (-16%; P controls 1.01 ml/mmHg; P ... systemic vascular resistance increased substantially (1083 versus 1378 dyn x s x cm-5, +27%; P blood pressure (-6%; P blood flow (-22%; P ... with beta-blockers increases small vessel (arteriolar) vascular tone towards the normal level, but does not affect the elevated compliance of the larger arteries in patients with cirrhosis....

  12. Intracellular responses to frequency modulated tones in the dorsal cortex of the mouse inferior colliculus

    Directory of Open Access Journals (Sweden)

    Ruediger eGeis

    2013-01-01

    Full Text Available Frequency modulations occur in many natural sounds, including vocalizations. The neuronal response to frequency modulated (FM stimuli has been studied extensively in different brain areas, with an emphasis on the auditory cortex and the central nucleus of the inferior colliculus. Here, we measured the responses to FM sweeps in whole-cell recordings from neurons in the dorsal cortex of the mouse inferior colliculus. Both up- and downward logarithmic FM sweeps were presented at two different speeds to both the ipsi- and the contralateral ear. Based on the number of action potentials that were fired, between 10-24% of cells were selective for rate or direction of the FM sweeps. A somewhat lower percentage of cells, 6-21%, showed selectivity based on EPSP size. To study the mechanisms underlying the generation of FM selectivity, we compared FM responses with responses to simple tones in the same cells. We found that if pairs of neurons responded in a similar way to simple tones, they generally also responded in a similar way to FM sweeps. Further evidence that FM selectivity can be generated within the dorsal cortex was obtained by reconstructing FM sweeps from the response to simple tones using three different models. In about half of the direction selective neurons the selectivity was generated by spectrally asymmetric synaptic inhibition. In addition, evidence for direction selectivity based on the timing of excitatory responses was also obtained in some cells. No clear evidence for the local generation of rate selectivity was obtained. We conclude that FM direction selectivity can be generated within the dorsal cortex of the mouse inferior colliculus by multiple mechanisms.

  13. Auditory brainstem responses to clicks and tone bursts in C57 BL/6J mice.

    Science.gov (United States)

    Scimemi, P; Santarelli, R; Selmo, A; Mammano, F

    2014-08-01

    In auditory research, hearing function of mouse mutants is assessed in vivo by evoked potential recording. Evaluation of the response parameters should be performed with reference to the evoked responses recorded from wild-type mice. This study reports normative data calculated on auditory brainstem responses (ABRs) obtained from 20 wild-type C57 BL/6J mice at a postnatal age between 21 and 45 days. Acoustic stimuli consisted tone bursts at 8, 14, 20, 26, 32 kHz, and clicks. Each stimulus was delivered in free field at stimulation intensity starting from a maximum of 100 dB peak equivalent SPL (dB peSPL) at decreasing steps of 10 dB with a repetition rate of 13/sec. Evoked responses were recorded by needle electrodes inserted subcutaneously. At high intensity stimulation, five response waveforms, each consisting of a positive peak and a subsequent negative valley, were identified within 7 msec, and were labelled with sequential capital Roman numerals from I to V. Peak IV was the most robust and stable at low intensities for both tone burst and click stimuli, and was therefore utilized to estimate hearing thresholds. Both latencies and amplitudes of ABR peaks showed good reproducibility with acceptable standard deviations. Mean wave IV thresholds measured across all animals ranged from a maximum of 23 dB peSPL for clicks to a minimum of 7 dB peSPL for 20 kHz-tone burst stimuli. Statistical analysis of the distribution of latencies and amplitudes of peaks from I to V performed for each stimulus type yielded a normative data set which was utilised to obtain the most consistent fitting-curve model. This could serve as a reference for further studies on murine models of hearing loss.

  14. An offset tone based gain stabilization technique for mixed-signal RF measurement systems

    Science.gov (United States)

    Joshi, Gopal; Motiwala, Paresh D.; Randale, G. D.; Singh, Pitamber; Agarwal, Vivek; Kumar, Girish

    2015-09-01

    This paper describes a gain stabilization technique for a RF signal measurement system. A sinusoidal signal of known amplitude, phase and close enough in frequency is added to the main, to be measured RF signal at the input of the analog section. The system stabilizes this offset tone in the digital domain, as it is sampled at the output of the analog section. This process generates a correction factor needed to stabilize the magnitude of the gain of the analog section for the main RF signal. With the help of a simple calibration procedure, the absolute amplitude of the main RF signal can be measured. The technique is especially suited for a system that processes signals around a single frequency, employs direct signal conversion into the digital domain, and processes subsequent steps in an FPGA. The inherent parallel signal processing in an FPGA-based implementation allows a real time stabilization of the gain. The effectiveness of the technique is derived from the fact, that the gain stabilization stamped to the main RF signal measurement branch requires only a few components in the system to be inherently stable. A test setup, along with experimental results is presented from the field of RF instrumentation for particle accelerators. Due to the availability of a phase synchronized RF reference signal in these systems, the measured phase difference between the main RF and the RF reference is also stabilized using this technique. A scheme of the signal processing is presented, where a moving average filter has been used to filter out not only the unwanted frequencies, but also to separate the main RF signal from the offset tone signal. This is achieved by a suitable choice of sampling and offset tone frequencies. The presented signal processing scheme is suitable to a variety of RF measurement applications.

  15. Numerical simulation of the generation mechanism of axisymmetric supersonic jet screech tones

    Science.gov (United States)

    Li, X. D.; Gao, J. H.

    2005-08-01

    In this paper an axisymmetric computational aeroacoustic procedure is developed to investigate the generation mechanism of axisymmetric supersonic jet screech tones. The axisymmetric Navier-Stokes equations and the two equations standard k-ɛ turbulence model modified by Turpin and Troyes ["Validation of a two-equation turbulence model for axisymmetric reacting and non-reaction flows," AIAA Paper No. 2000-3463 (2000)] are solved in the generalized curvilinear coordinate system. A generalized wall function is applied in the nozzle exit wall region. The dispersion-relation-preserving scheme is applied for space discretization. The 2N storage low-dissipation and low-dispersion Runge-Kutta scheme is employed for time integration. Much attention is paid to far-field boundary conditions and turbulence model. The underexpanded axisymmetric supersonic jet screech tones are simulated over the Mach number from 1.05 to 1.2. Numerical results are presented and compared with the experimental data by other researchers. The simulated wavelengths of A0, A1, A2, and B modes and part of simulated amplitudes agree very well with the measurement data by Ponton and Seiner ["The effects of nozzle exit lip thickness on plume resonance," J. Sound Vib. 154, 531 (1992)]. In particular, the phenomena of modes jumping have been captured correctly although the numerical procedure has to be improved to predict the amplitudes of supersonic jet screech tones more accurately. Furthermore, the phenomena of shock motions are analyzed. The predicted splitting and combination of shock cells are similar with the experimental observations of Panda ["Shock oscillation in underexpanded screeching jets," J. Fluid. Mech. 363, 173 (1998)]. Finally, the receptivity process is numerically studied and analyzed. It is shown that the receptivity zone is associated with the initial thin shear layer, and the incoming and reflected sound waves.

  16. Constraints of Tones, Vowels and Consonants on Lexical Selection in Mandarin Chinese.

    Science.gov (United States)

    Wiener, Seth; Turnbull, Rory

    2016-03-01

    Previous studies have shown that when speakers of European languages are asked to turn nonwords into words by altering either a vowel or consonant, they tend to treat vowels as more mutable than consonants. These results inspired the universal vowel mutability hypothesis: listeners learn to cope with vowel variability because vowel information constrains lexical selection less tightly and allows for more potential candidates than does consonant information. The present study extends the word reconstruction paradigm to Mandarin Chinese--a Sino-Tibetan language, which makes use of lexically contrastive tone. Native speakers listened to word-like nonwords (e.g., su3) and were asked to change them into words by manipulating a single consonant (e.g., tu3), vowel (e.g., si3), or tone (e.g., su4). Additionally, items were presented in a fourth condition in which participants could change any part. The participants' reaction times and responses were recorded. Results revealed that participants responded faster and more accurately in both the free response and the tonal change conditions. Unlike previous reconstruction studies on European languages, where vowels were changed faster and more often than consonants, these results demonstrate that, in Mandarin, changes to vowels and consonants were both overshadowed by changes to tone, which was the preferred modification to the stimulus nonwords, while changes to vowels were the slowest and least accurate. Our findings show that the universal vowel mutability hypothesis is not consistent with a tonal language, that Mandarin tonal information is lower-priority than consonants and vowels and that vowel information most tightly constrains Mandarin lexical access. PMID:27089806

  17. Left main coronary artery compression in pulmonary arterial hypertension

    DEFF Research Database (Denmark)

    Al-Badri, Kadhem Helo Abbas; Jensen, Jesper Møller; Christiansen, Evald H;

    2015-01-01

    In patients with pulmonary arterial hypertension (PAH), chest pain is most likely due to right ventricular demand ischemia. We report a patient with idiopathic PAH who developed severe angina due to extrinsic compression of the left main coronary artery (LMCA) from a dilated pulmonary artery trunk....... The diagnosis was verified by electrocardiogram after exercise, coronary angiography including intravascular ultrasound, and cardiac multidetector computed tomography (MDCT). The origin of the LMCA was high in the left coronary sinus, facilitating extrinsic compression. The patient was successfully treated...

  18. Spontaneous Coronary Artery Dissection.

    Science.gov (United States)

    Tweet, Marysia S; Gulati, Rajiv; Hayes, Sharonne N

    2016-07-01

    Spontaneous coronary artery dissection is an important etiology of nonatherosclerotic acute coronary syndrome, myocardial infarction, and sudden death. Innovations in the catheterization laboratory including optical coherence tomography and intravascular ultrasound have enhanced the ability to visualize intimal disruption and intramural hematoma associated with SCAD. Formerly considered "rare," these technological advances and heightened awareness suggest that SCAD is more prevalent than prior estimates. SCAD is associated with female sex, young age, extreme emotional stress, or extreme exertion, pregnancy, and fibromuscular dysplasia. The clinical characteristics and management strategies of SCAD patients are different than for atherosclerotic heart disease and deserve specific consideration. This review will highlight recent discoveries about SCAD as well as describe current efforts to elucidate remaining gaps in knowledge.

  19. Spontaneous Coronary Artery Dissection.

    Science.gov (United States)

    Tweet, Marysia S; Gulati, Rajiv; Hayes, Sharonne N

    2016-07-01

    Spontaneous coronary artery dissection is an important etiology of nonatherosclerotic acute coronary syndrome, myocardial infarction, and sudden death. Innovations in the catheterization laboratory including optical coherence tomography and intravascular ultrasound have enhanced the ability to visualize intimal disruption and intramural hematoma associated with SCAD. Formerly considered "rare," these technological advances and heightened awareness suggest that SCAD is more prevalent than prior estimates. SCAD is associated with female sex, young age, extreme emotional stress, or extreme exertion, pregnancy, and fibromuscular dysplasia. The clinical characteristics and management strategies of SCAD patients are different than for atherosclerotic heart disease and deserve specific consideration. This review will highlight recent discoveries about SCAD as well as describe current efforts to elucidate remaining gaps in knowledge. PMID:27216840

  20. A case of primitive persistent hypoglossal artery

    Energy Technology Data Exchange (ETDEWEB)

    Park, C. K.; Koh, B. H.; Kim, Y. S.; Kang, S. R. [Hangyang University College of Medicine, Seoul (Korea, Republic of)

    1979-06-15

    Three kinds of carotid-basilar anastomosis have been found, they were named as persistent primitive trigeminal artery, persistent primitive acoustic (or otic) artery and persistent primitive hypoglossal artery, among them, the persistent primitive hypoglossal artery is by far the least common type of the internal carotid-basilar anastomosis which have been demonstrate in human postembryonic stages. Persistent primitive by hypoglossal artery is usually found incidentally. This vascular anomaly, however,have been reported to be associated with multiple congenital anomalies, such as unilateral or bilateral vertebral artery hypoplasia, absence of the posterior communicating artery, hypoplasia of the proximal portion of the posterior cerebral artery, aneurysm of the circle of Willis, the origin of both pericallosal arteries from a single anterior cerebral artery, retarded mental development dating from infancy, carotid-cavernous fistula formation etc. A case of persistent primitive hypoglossal artery in an young Korean male was reported with brief review of the literature.