It has long been known that environmental conditions, particularly during development, affect morphological and functional properties of the brain including sensory systems; manipulating the environment thus represents a viable way to explore experience-dependent plasticity of the brain as well as of sensory systems. In this review, we summarize our experience with the effects of acoustically enriched environment (AEE) consisting of spectrally and temporally modulated complex sounds applied during first weeks of the postnatal development in rats and compare it with the related knowledge from the literature. Compared to controls, rats exposed to AEE showed in neurons of several parts of the auditory system differences in the dendritic length and in number of spines and spine density. The AEE exposure permanently influenced neuronal representation of the sound frequency and intensity resulting in lower excitatory thresholds, increased frequency selectivity and steeper rate-intensity functions. These changes were present both in the neurons of the inferior colliculus and the auditory cortex (AC). In addition, the AEE changed the responsiveness of AC neurons to frequency modulated, and also to a lesser extent, amplitude-modulated stimuli. Rearing rat pups in AEE leads to an increased reliability of acoustical responses of AC neurons, affecting both the rate and the temporal codes. At the level of individual spikes, the discharge patterns of individual neurons show a higher degree of similarity across stimulus repetitions. Behaviorally, rearing pups in AEE resulted in an improvement in the frequency resolution and gap detection ability under conditions with a worsened stimulus clarity. Altogether, the results of experiments show that the exposure to AEE during the critical developmental period influences the frequency and temporal processing in the auditory system, and these changes persist until adulthood. The results may serve for interpretation of the effects of the application of enriched acoustical environment in human neonatal medicine, especially in the case of care for preterm born children.
- MeSH
- akustická stimulace * MeSH
- akustika MeSH
- colliculus inferior růst a vývoj fyziologie MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- neurony fyziologie MeSH
- neuroplasticita * fyziologie MeSH
- novorozená zvířata MeSH
- sluchová dráha * růst a vývoj fyziologie MeSH
- sluchová percepce MeSH
- sluchové korové centrum * růst a vývoj fyziologie MeSH
- věkové faktory MeSH
- životní prostředí MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Voice registers are assumed to be related to different laryngeal adjustments, but objective evidence has been insufficient. While chest register is usually associated with the lower pitch range, and head register with the higher pitch range, here we investigated a professional singer who claimed an ability to produce both these registers at every pitch, throughout her entire singing range. The singer performed separated phonations alternating between the two registers (further called chest-like and head-like) at all pitches from C3 (131 Hz) to C6 (1047 Hz). We monitored the vocal fold vibrations using high-speed video endoscopy and electroglottography. The microphone sound was recorded and used for blind listening tests performed by the three authors (insiders) and by six "naive" participants (outsiders). The outsiders correctly identified the registers in 64% of the cases, and the insiders in 89% of the cases. Objective analysis revealed larger closed quotient and vertical phase differences for the chest-like register within the lower range below G4 (<392 Hz), and also a larger closed quotient at the membranous glottis within the higher range above Bb4 (>466 Hz), but not between Ab4-A4 (415-440 Hz). The normalized amplitude quotient was consistently lower in the chest-like register throughout the entire range. The results indicate that that the singer employed subtle laryngeal control mechanisms for the chest-like and head-like phonations on top of the traditionally recognized low-pitched chest and high-pitched head register phenomena. Across all pitches, the chest-like register was produced with more rapid glottal closure that was usually, but not necessarily, accompanied also by stronger adduction of membranous glottis. These register changes were not always easily perceivable by listeners, however.
- MeSH
- akustika * MeSH
- audiovizuální záznam MeSH
- biomechanika MeSH
- dospělí MeSH
- elektrodiagnostika MeSH
- fonace * MeSH
- hlasové řasy fyziologie MeSH
- kvalita hlasu * MeSH
- laryngoskopie MeSH
- larynx fyziologie MeSH
- lidé MeSH
- vibrace MeSH
- zpívání * MeSH
- zvuková spektrografie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- MeSH
- dávka záření MeSH
- diagnostické zobrazování * metody MeSH
- diferenciální diagnóza MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- pediatrie * metody MeSH
- pneumologie * metody MeSH
- počítačová rentgenová tomografie metody přístrojové vybavení MeSH
- pozitronová emisní tomografie metody MeSH
- radiografie metody přístrojové vybavení MeSH
- radioisotopová scintigrafie metody MeSH
- ultrazvuk metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
OBJECTIVES: Stroke volume (SV) and cardiac output monitoring is a cornerstone of hemodynamic assessment. Noninvasive technologies are increasingly used in children. This study compared SV measurements obtained by transcutaneous Doppler ultrasound techniques (ultrasonic cardiac output monitor [USCOM]), transthoracic echocardiography jugular (TTE-J), and parasternal (TTE-P) views performed by pediatric intensivists (OP-As) with limited training in cardiac sonography (20 previous examinations) and pediatric cardiologists (OP-Bs) with limited training in USCOM (30 previous examinations) in spontaneously ventilating children. METHODS: A single-center study was conducted in 37 children. Each operator obtained 3 sets of USCOM SV measurements within a period of 3 to 5 minutes, followed with TTE measurements from both apical and jugular views. The investigators were blinded to each other's results to prevent visual and auditory bias. RESULTS: Both USCOM and TTE methods were applicable in 89% of patients. The intraobserver variability of USCOM, TTE-J, and TTE-P were less than 10% in both investigators. The SV measurements by OP-As using USCOM, TTE-J, and TTE-P were 46.15 (25.48) mL, 39.45 (20.65) mL, and 33.42 (16.69) mL, respectively. The SV measurements by OP-Bs using USCOM, TTE-J, and TTE-P were 43.99 (25.24) mL, 38.91 (19.98) mL, and 37.58 (19.81) mL, respectively.The percentage error in SV with USCOM relative to TTE-J was 36% in OP-As and 37% in OP-Bs. The percentage error in SV with TTE-P was 33% relative to TTE-J in OP-As and 21% in OP-Bs. CONCLUSIONS: Our findings show that the methods are not interchangeable because SV values by USCOM are higher in comparison with the SV values obtained by TTE. Both methods have low level of intraobserver variability. The SV measurements obtained by TTE-P were significantly lower compared with the TTE-J for the operator with limited training in echocardiography. The TTE-P requires longer practice compared with the TTE-J; therefore, we recommend to prefer TTE-J to TTE-P for inexperienced operators.
BACKGROUND: Motor skills in children have traditionally been examined via challenging speech tasks such as syllable repetition, and calculating the syllabic rate using a stopwatch or by inspecting the oscillogram followed by a laborious comparison of the scores on a look-up table representing the typical performances of children of the given age and sex. As the commonly used performance tables are over-simplified to allow for manual scoring, we raise the question of whether a computational model of motor skills development could be more informative, and could allow for the automated screening of children to detect underdeveloped motor skills. METHODS: We recruited a total of 275 children aged four to 15 years. All the participants were native Czech speakers with no history of hearing or neurological impairments. We recorded each child's performance of/pa/-/ta/-/ka/syllable repetition. Various parameters of diadochokinesis (DDK; DDK rate, DDK regularity, voice onset time [VOT] ratio, syllable, vowel and VOT duration) were investigated in the acoustic signals using supervised reference labels. Female and male participants were analyzed separately by comparing younger, middle, and older age groups of children via ANOVA. Finally, we implemented a fully automated model that estimated the developmental age of a child based on the acoustic signal, and evaluated its accuracy using Pearson's correlation coefficient and normalized root-mean-squared errors (RMSEs). RESULTS: The DDK rate reflected the ages of the children proportionally (p < 0.001). Other DDK parameters also showed strong sensitivity to age (p < 0.001), with the exception of VOT duration, which had a smaller effect (p = 0.091). The effect of age was found to be sex specific for the syllable length (p < 0.001) and DDK rate (p = 0.003). We observed that females spoke more slowly and had a longer VOT at preschool age (p < 0.001). The DDK rate obtained via the automated algorithm was strongly correlated with the reference (p < 0.001, Pearson's correlation coefficient of 0.97), with a low normalized RMSE of 3.77%. CONCLUSIONS: As children develop their motor skills, they are capable of shortening the vowels to increase the rate of syllabic repetitions. The nonlinear development in childhood and adolescence, with a steady state in adulthood, follows a logistic function for the DDK rate. This study demonstrates that the development of motor skills can be examined sensitively and more appropriately by a fully automated noninvasive procedure that also accounts for the dispersion of values within age brackets.
- MeSH
- akustika MeSH
- dítě MeSH
- hlas * MeSH
- jazyk (prostředek komunikace) MeSH
- lidé MeSH
- mladiství MeSH
- předškolní dítě MeSH
- řeč * MeSH
- senioři MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
In this tribute article to D.G. Miller, we review some historical and recent contributions to understanding the myoelastic-aerodynamic (MEAD) theory of phonation and the related acoustic phenomena in subglottal and vocal tract. At the time of the formulation of MEAD by van den Berg in late 1950s, it was assumed that vocal fold oscillations are self-sustained thanks to increased subglottal pressure pushing the glottis to open and decreased subglottal pressure allowing the glottis to close. In vivo measurements of subglottal pressures during phonation invalidated these assumptions, however, and showed that at low fundamental frequencies subglottal pressure rather tends to reach a maximum value at the beginning of glottal closure and then exhibits damped oscillations. These events can be interpreted as transient acoustic resonance phenomena in the subglottal tract that are triggered by glottal closure. They are analogous to the transient acoustic phenomena seen in the vocal tract. Rather than subglottal pressure oscillations, a more efficient mechanism of transfer of aerodynamic energy to the vocal fold vibrations has been identified in the vertical phase differences (mucosal waves) making the glottal shape more convergent during glottis opening than during glottis closing. Along with other discoveries, these findings form the basis of our current understanding of MEAD.
There is an increasing interest in acoustics for microfluidic applications. This field, commonly known as acoustofluidics involves the interaction of ultrasonic standing waves with fluids and dispersed microparticles. The combination of microfluidics and the so-called acoustic standing waves (ASWs) led to the development of integrated systems for contact-less on-chip cell and particle manipulation where it is possible to move and spatially localize these particles based on the different acoustophysical properties. While it was initially suggested that the acoustic forces could be harmful to the cells and could impact cell viability, proliferation, or function via phenotypic or even genotypic changes, further studies disproved such claims. This review is summarizing some interesting applications of acoustofluidics in the manipulations of biomaterials, such as cells or subcellular vesicles, in works published mainly within the last 5 years.
Poslech pouhým uchem přiloženým na povrch těla nemocného byl využíván již ve středověku. Takto získané informace však bylo obtížné přesněji lokalizovat, a tím i diagnosticky využít. V r. 1816 francouzský lékař René Théophile Hyacinthe Laënnec (nar. 17. 2. 1781 v městečku Quimper ve Francii) poprvé použil k poslechu srdce nemocné pacientky stočeného listu papíru, pomocí kterého slyšel srdeční ozvy a další zvuky daleko jasněji. Následně při výrobě poslechových válců experimentoval s různými materiály. Ukázalo se, že ty z papíru, dřeva nebo indické třtiny jsou pro přenos zvuku nejvhodnější. Nakonec zvolil jako nejlepší surovinu dřevo keře zimostráz. Svůj poslechový nástroj označil jako le cylendre. Teprve později se ujal název stetoskop. Laënnec byl v roce 1822 jmenován profesorem medicíny na College de France a o rok později profesorem na Hôpital de la Charité v Paříži. Zemřel 13. srpna 1826 v Kerlouanu na pokročilou tuberkulózu. Je považován za otce lékařského poslechu.
Auscultation with just the ear placed on the surface of the patient‘s body was already used in the Middle Ages. However, the information obtained in this way was difficult to locate more precisely and thus to use diagnostically. In 1816, the French physician René Théophile Hyacinthe Laënnec (b. 17/02/1781 in the town of Quimper, France) first used a rolled sheet of paper to listen to the heart of a sick patient, with which he could hear heart sounds and other sounds much more clearly. Subsequently, he experimented with different materials in the production of listening cylinders. Those made of paper, wood, or Indian cane have been found to be most suitable for transmitting sound. In the end, he chose the wood of boxwood as the best raw material. He labeled his listening instrument le cylendre. It was only later that the name stethoscope was adopted. Laënnec was appointed professor of medicine at the College de France in 1822 and a year later professor at the Hôpital de la Charité in Paris. He died on 13 August 1826 in Kerlouan of advanced tuberculosis. He is considered the father of clinical auscultation.
- MeSH
- akustika MeSH
- dějiny 19. století MeSH
- fyzikální jevy MeSH
- lidé MeSH
- poslech * dějiny přístrojové vybavení MeSH
- stetoskopy dějiny MeSH
- Check Tag
- dějiny 19. století MeSH
- lidé MeSH
- Publikační typ
- historické články MeSH
Článek si klade za cíl odpovědět na otázku, které z četných prací publikovaných s tématikou regionální anestezie má dosah do běžné klinické praxe v českých zemích. Vedle výsledků velkých studií a zajímavých článků uvádíme v návaznosti na přehled z loňského roku [1] zcela recentní výsledek konsenzuálního procesu expertů o identifikaci anatomických struktur u blokád střední a vyšší obtížnosti. Domníváme se, že logika tohoto koncenzu nabízí návod na standardizaci výuky ultrazvukové asistence v regionální anestezii.
This article aims to select recently published regional anesthesia articles, especially those with the highest impact on common clinical practice in our country. We present the most recent recommendations for anatomical structures to identify on ultrasound for the performance of intermediate and advanced blocks in ultrasound-guided regional an esthesia in addition to the results of big data trials and other interesting articles. We believe that the outcomes of this consensus can offer support for the standardization of education in ultrasound-guided regional anesthesia.
- MeSH
- dolní končetina MeSH
- horní končetina MeSH
- lidé MeSH
- směrnice pro lékařskou praxi jako téma MeSH
- svodná anestezie * MeSH
- trup MeSH
- ultrazvuk MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
