Inefficiencies in Motor Strategies of Horn Players with Embouchure Dystonia: Comparisons to Elite Performers

2016 ◽  
Vol 31 (2) ◽  
pp. 69-77 ◽  
Author(s):  
Peter W Iltis ◽  
Jens Frahm ◽  
Dirk Voit ◽  
Arun Joseph ◽  
Rachel Burke ◽  
...  

OBJECTIVE: Motor control of the muscles of the face, lips, and tongue of horn players has traditionally been described from externally observed phenomena. Developments in real-time, high-speed magnetic resonance imaging (MRI) extend the scope of study to include descriptive and quantitative information from within the mouth. We employed these developments to compare oral movement strategies between 12 elite horn players and 5 horn players with embouchure dystonia (ED). METHODS: Serial images with an acquisition time of 33.3 ms were obtained from each subject as they performed 6 exercises on an MRI-compatible horn: 1) a slurred ascending harmonic sequence, 2) a slurred descending harmonic sequence, 3–6) sustained high and low notes, each performed softly and loudly. Temporal changes in pixel luminescence along a series of lines positioned within the oral cavity were calculated using a customized MATLAB toolkit. This allowed the extraction of temporal line profiles for comparative analyses between elite and dystonic horn players. RESULTS: Differing motor strategies of controlling the tongue and jaw were observed during ascending and descending exercises. In ascending exercises, the elite players employed a strategy of elevation and anterior tongue displacement and elevation of the jaw, whereas dystonic players exhibited more variability in their responses. With descending exercises, both groups exhibited a lowering of the tongue and jaw, though this was more pronounced and consistent in the elite horn players. Sustained note exercises also elicited differences between groups. We suggest that elite strategies are more efficient and that the less-efficient patterns of dystonic players may exacerbate muscular tension with ED.

Author(s):  
R.D. Leapman ◽  
S.B. Andrews

Elemental mapping of biological specimens by electron energy loss spectroscopy (EELS) can be carried out both in the scanning transmission electron microscope (STEM), and in the energy-filtering transmission electron microscope (EFTEM). Choosing between these two approaches is complicated by the variety of specimens that are encountered (e.g., cells or macromolecules; cryosections, plastic sections or thin films) and by the range of elemental concentrations that occur (from a few percent down to a few parts per million). Our aim here is to consider the strengths of each technique for determining elemental distributions in these different types of specimen.On one hand, it is desirable to collect a parallel EELS spectrum at each point in the specimen using the ‘spectrum-imaging’ technique in the STEM. This minimizes the electron dose and retains as much quantitative information as possible about the inelastic scattering processes in the specimen. On the other hand, collection times in the STEM are often limited by the detector read-out and by available probe current. For example, a 256 x 256 pixel image in the STEM takes at least 30 minutes to acquire with read-out time of 25 ms. The EFTEM is able to collect parallel image data using slow-scan CCD array detectors from as many as 1024 x 1024 pixels with integration times of a few seconds. Furthermore, the EFTEM has an available beam current in the µA range compared with just a few nA in the STEM. Indeed, for some applications this can result in a factor of ~100 shorter acquisition time for the EFTEM relative to the STEM. However, the EFTEM provides much less spectral information, so that the technique of choice ultimately depends on requirements for processing the spectrum at each pixel (viz., isolated edges vs. overlapping edges, uniform thickness vs. non-uniform thickness, molar vs. millimolar concentrations).


Author(s):  
Kazuyuki Koike ◽  
Hideo Matsuyama

Spin-polarized scanning electron microscopy (spin SEM), where the secondary electron spin polarization is used as the image signal, is a novel technique for magnetic domain observation. Since its first development by Koike and Hayakawa in 1984, several laboratories have extensively studied this technique and have greatly improved its capability for data extraction and its range of applications. This paper reviews the progress over the last few years.Almost all the high expectations initially held for spin SEM have been realized. A spatial resolution of several hundreds angstroms has been attained, which is nearly one order of magnitude higher than that of conventional methods for thick samples. Quantitative analysis of magnetization direction has been performed more easily than with conventional methods. Domain observation of the surface of three-dimensional samples has been confirmed to be possible. One of the drawbacks, a long image acquisition time, has been eased by combining highspeed image-signal processing with high speed scanning, although at the cost of image quality. By using spin SEM, the magnetic structure of a 180 degrees surface Neel wall, magnetic thin films, multilayered films, magnetic discs, etc., have been investigated.


Author(s):  
K. Bobzin ◽  
M. Öte ◽  
M. A. Knoch ◽  
I. Alkhasli ◽  
H. Heinemann

AbstractIn plasma spraying, instabilities and fluctuations of the plasma jet have a significant influence on the particle in-flight temperatures and velocities, thus affecting the coating properties. This work introduces a new method to analyze the stability of plasma jets using high-speed videography. An approach is presented, which digitally examines the images to determine the size of the plasma jet core. By correlating this jet size with the acquisition time, a time-dependent signal of the plasma jet size is generated. In order to evaluate the stability of the plasma jet, this signal is analyzed by calculating its coefficient of variation cv. The method is validated by measuring the known difference in stability between a single-cathode and a cascaded multi-cathode plasma generator. For this purpose, a design of experiment, covering a variety of parameters, is conducted. To identify the cause of the plasma jet fluctuations, the frequency spectra are obtained and subsequently interpreted by means of the fast Fourier transformation. To quantify the significance of the fluctuations on the particle in-flight properties, a new single numerical parameter is introduced. This parameter is based on the fraction of the time-dependent signal of the plasma jet in the relevant frequency range.


2019 ◽  
Vol 92 (1102) ◽  
pp. 20190109 ◽  
Author(s):  
Fengdan Wang ◽  
Haiping Zhang ◽  
Chanyuan Wu ◽  
Qian Wang ◽  
Bo Hou ◽  
...  

Objective: Dermatomyositis (DM) and polymyositis (PM) make up the largest group of potentially treatable myopathies and require early diagnosis. This study investigates whether the edema of thigh muscles in DM/PM can be quantitatively assessed by a novel accelerated T2 mapping technique—GRAPPATINI. Methods: Three conventional MR sequences and GRAPPATINI accelerated T2 mapping of bilateral thighs from 20 patients (7 DM and 13 PM) and 10 healthy volunteers were prospectively carried out on a 3 T MR scanner. Afterwards, T2 values of 477 thigh muscles from the patients and the healthy controls were manually measured. In addition, the correlations between T2 values and serum muscle enzymes in patients were also analyzed. Results: The new GRAPPATINI technique made quantitative T2 mapping of bilateral thighs feasible with a scanning time of only 2 min 18 s. Moreover, GRAPPATINI-generated T2 values of muscles from patients were markedly higher than those from healthy subjects (p < 0.001). GRAPPATINI accelerated T2 mapping appeared a more sensitive technique in that some DM/PM muscles appearing normal per conventional MRI had increased T2 relaxation time. Furthermore, GRAPPATINI-generated T2 values of DM/PM thigh muscles positively correlated with serum enzyme levels (p < 0.001), which reflected the severity of myopathy. Conclusion: GRAPPATINI can significantly shorten acquisition time of T2 mapping and may potentially be applied clinically in DM and PM. Advances in knowledge: GRAPPATINI acceleration makes T2 mapping feasible in clinical practice in providing quantitative information regarding thigh muscle inflammation in DM and PM.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Osnat Luxenburg ◽  
Mor Saban ◽  
Vicki Myers ◽  
Sharona Vaknin ◽  
Noga Boldor ◽  
...  

Abstract Background and purpose Marked reductions in imaging exams have been documented during the COVID-19 pandemic. The study aimed to examine the effect of the two waves of COVID-19 on magnetic resonance imaging (MRI) utilization at the national and regional level. Materials and methods A retrospective-archive study was conducted in Israel, comparing March–December 2020 with March–December 2018 and 2019. Data on MRI utilization were obtained from the national MRI registry, while data on confirmed COVID-19 cases, by place of residence, were obtained from the Israeli Ministry of Health open COVID-19 database. Results The number and rate of MRI examinations decreased during the first COVID-19 wave, with the steepest drop in April 2020: 47.5% relative decrease compared to April 2019, and 42.2% compared to 2018. This was followed by a compensatory increase between the waves and a return to almost pre-pandemic levels of use, with just a modest decrease, during the second, more intense COVID wave, compared with the previous year. Existing differences between regions increased during the pandemic. The rate ratio of MRI exams between Tel-Aviv and the Northern periphery increased from 2.89 in April 2019 to 3.94 in April 2020. Jerusalem metropolitan region, with the largest burden of COVID disease, demonstrated only a modest decrease (1%) in MRI utilization during the first 10 months of the pandemic. Conclusions At the national level, time trends in reduced MRI utilization followed the first wave of COVID-19, and were accompanied by increased regional disparities. These changes were not explained by differences in the burden of COVID-19 disease but might be explained by unequal distribution of MRI scanners among regions. Reduced utilization was not evident during the second wave, nor at the beginning of the third wave, despite higher COVID-19 case load, demonstrating adaptation to the new normal. Patterns of MRI utilization might help policy-makers and healthcare managers predict the behavior of imaging as well as other sectors, such as elective surgical procedures, during an ongoing pandemic. This forecast might help to manage the lasting effects of the pandemic, including extended waiting times, in the months and years following its remission. In preparation for future national emergencies, timely and detailed data on MRI utilization can serve as a “sensor” for a wide array of diagnostic and interventional medical activities, providing policy-makers with an updated snapshot to guide their response at the regional and national levels.


1992 ◽  
Vol 70 (10) ◽  
pp. 1886-1896 ◽  
Author(s):  
Véronique Goosse ◽  
Vincent L. Bels

High-speed cinematography (100 frames/s) was used to allow quantitative analysis of the kinematic profiles of tongue and jaw displacements during chemosensory activities in the scleroglossan lizard Lacerta viridis. The types of tongue flicking were simple downward extensions (SDE), single oscillations (SOC), and submultiple oscillations (SMOC) of the tongue out of the mouth. The SMOC type involves a downward or upward movement of the tongue performed before a typical oscillation and it is therefore suggested that this is an intermediate category of flick between the typical SOC and MOC of lizards. Closing and opening of the mouth in SDE, SOC, and SMOC cycles may or may not be separated by a stationary stage during which the jaws are held open at a constant gape. The duration of this stationary interval increases from SDE to SMOC. Gape cycles do not show any division into slow and fast stages. The gape is produced largely by depression of the lower jaw; the upper jaw is slightly elevated by protrusion of the tongue. Patterns of correlation of kinematic variables depicting jaw and tongue movements differed between SDE, SOC, and SMOC. A principal component analysis shows that the three flick types overlap in a multivariate space constructed from the kinematic variables depicting jaw and tongue displacements. Overlap between SOC and SMOC categories is greater than that between SOC, SMOC, and SDE categories. The kinematic patterns of tongue displacement during SMOC in Lacerta viridis show similarities with those of MOC in other lizards and in snakes. Kinematically, the pattern of jaw and tongue displacements of Lacerta viridis during chemosensory activities shows similarities with those that occur during drinking and prey capture.


Countering a quantum computer in the process of illegal ultra-high-speed decryption of messages is technically feasible. Information owner must oppose the competitor's computer with tasks, the solution of which requires an infinite number of operations during decryption. For example, the dependence of functions on an infinite number of informative features. The owner encrypts by integrating the functions, the recipient decrypts by solving the integral equations. It is not a discrete but an analog approach that prevails here. The basis for the implementation of this approach was created by Polish scientists. Mathematician Stefan Banach (1892-1945), who created modern functional analysis, and Marian Mazur (1909-1983), the author of " The Qualitative Theory of Information". Their theory was created in contrast with the "Quantitative Information Theory". Cryptologists who have devoted their whole lives to improving the "discrete" theory and found themselves close to power (and finance), try not to recall that Claude Shannon in his basic work "Communication Theory of Secrecy Systems" more than once emphasized the discrete focus of his developments anticipating future research on the specific limitations of his work adapted to the communication theory. Forgetting about the unlimited speeds and amounts of memory of quantum computers the orthodox talk about redundancy and further purely technical issues, including administrative leverages for counteracting against opponents. It is impossible to stop the progress of science. Experiments have shown the reality of creating such post-quantum-level cryptographic systems.


Author(s):  
A. Pinchuk ◽  
M. Garbuz ◽  
P. Zeleny ◽  
D. Harnets ◽  
D. Ivanov

Analysis of combat losses of aircraft in local armed conflicts in recent decades shows that most cases of aircraft hits are related to the impact of guided surface-to-air and air-to-air missiles equipped with homing warheads. The use of modern guided missiles equipped with homing warheads is one of the main threats to aircraft of various types. This is due to the fact that modern guided missiles are characterized by high speed, maneuverability, accuracy of aiming and difficulty of detection. Solving the problem of protecting aircraft from guided missiles consists of several stages: detection of missile launch; confirmation that the detected missile is heading directly toward the protected object; missile identification and decision-making on the most effective countermeasure system employment. At present, there are no missile launch detection systems that guarantee a 100% probability of threat detection, but an analysis of aviation combat losses in local armed conflicts in recent decades convincingly shows that the number of combat losses of aircraft equipped with such systems is much lower than those in which missile launch detection is carried out visually. For example, most of the Soviet Union's losses during the war in Afghanistan and the United States‟ losses during Operation “Desert Storm” in Iraq were related to the use of portable anti-aircraft missile systems, which missiles were equipped with infrared homing warheads. Realizing the scale of the threat posed by such missiles, most of the world's leading countries have significantly increased the expenses on development new or improvement existing countermeasures. As a result, the aggregate losses of coalition forces in Iraq, Afghanistan and Syria since 2001 clearly suggest that these costs have paid off, with losses from the use of portable anti-aircraft missile systems significantly reduced, while the total number of combat sorties increased. Therefore, in the face of all the challenges and threats posed to Ukraine due to the aggressive actions of the Russian Federation, conducting research in the interests of aviation of the Armed Forces of Ukraine to improve the effectiveness of missile detection systems for ensuring timely detection of threats, warning of aircraft crew and activation in the automatic mode the means of countermeasures is as relevant as ever.


2021 ◽  
Vol 11 (8) ◽  
pp. 2211-2221
Author(s):  
Yuanbo Xie ◽  
Haitao Jiang ◽  
Hongwei Du ◽  
Jinzhang Xu ◽  
Bensheng Qiu

Alzheimer’s Disease (AD) is a progressive and irreversible neurodegenerative condition, which results in dementia. Mild Cognitive Impairment (MCI) is an intermediate state between normal aging and AD. Instead of traditional questionnaire method, magnetic resonance imaging (MRI) can be used by radiologists to diagnose and screening AD recently, but long acquisition time is not conducive to screening AD and MCI. To solve this problem, we develop a Fasu-Net (Fast Alzheimer’s disease Screening neural network with Undersampled MRI) for AD and MCI clinical classification. The network uses undersampled structural MRI with a shorter acquisition time to improve the screening and diagnosis efficiency of AD. For achieving the best classification result, three axial planes of brain MR images were feed into the Fasu-Net with transfer learning method. The experiment results on undersampled 3D T1-weighted images database (ADNI) show that in the AD versus MCI versus HC (Healthy Controls) classification, the Fasu-Net achieved the accuracy of 91.41%, thus can be a potential method for fast clinical screening of AD.


2018 ◽  
Vol 39 (12) ◽  
pp. 2419-2432 ◽  
Author(s):  
Catherine J Scott ◽  
Jieqing Jiao ◽  
Andrew Melbourne ◽  
Ninon Burgos ◽  
David M Cash ◽  
...  

Pharmacokinetic modelling on dynamic positron emission tomography (PET) data is a quantitative technique. However, the long acquisition time is prohibitive for routine clinical use. Instead, the semi-quantitative standardised uptake value ratio (SUVR) from a shorter static acquisition is used, despite its sensitivity to blood flow confounding longitudinal analysis. A method has been proposed to reduce the dynamic acquisition time for quantification by incorporating cerebral blood flow (CBF) information from arterial spin labelling (ASL) magnetic resonance imaging (MRI) into the pharmacokinetic modelling. In this work, we optimise and validate this framework for a study of ageing and preclinical Alzheimer's disease. This methodology adapts the simplified reference tissue model (SRTM) for a reduced acquisition time (RT-SRTM) and is applied to [18F]-florbetapir PET data for amyloid-β quantification. Evaluation shows that the optimised RT-SRTM can achieve amyloid burden estimation from a 30-min PET/MR acquisition which is comparable with the gold standard SRTM applied to 60 min of PET data. Conversely, SUVR showed a significantly higher error and bias, and a statistically significant correlation with tracer delivery due to the influence of blood flow. The optimised RT-SRTM produced amyloid burden estimates which were uncorrelated with tracer delivery indicating its suitability for longitudinal studies.


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