Search

Start Over Format bez média Language English

693. Ailinella mirabilis gen. n., sp. n. (Eucestoda: Pseudophyllidea) from Galaxias maculatus (Pisces: Galaxiidae) in the Andean-Patagonian region of Argentina

Creator:
Pertierra, Alicia A. Gil de and Semenas, Liliana G.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Pseudophyllidea, Triaenophoridae, Ailinella mirabilis, microtriches, tumuli, Galaxias maculatus, and Patagonia
Language:
English
Description:
Ailinella gen. n. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate Ailinella mirabilis sp. n. from Galaxias maculatus (Jenyns, 1842), a freshwater fish inhabiting the Andean lakes in Argentinean Patagonia. Ailinella belongs to the Triaenophoridae because it has a marginal genital pore, a follicular vitelline gland, and a ventral uterine pore. The new genus can be distinguished from other triaenophorids by the following combination of characters: a small body size, a low number of proglottides, which are longer than wide, a truncated pyramidal to globular scolex, a rectangular apical disc, presence of the neck, lack of internal longitudinal musculature separating the cortex from the medulla, testes distributed in one central field surrounding the ovary laterally and posteriorly, the vagina predominantly anterior to the cirrus sac, vitelline follicles circum-medullary, the genital pores post-equatorial, a saccate uterus, and operculate eggs. Blade-like spiniform microtriches were present on all tegument surfaces, and tumuli on all surfaces of the scolex and the anterior surface of the neck. Microtriches were characterized according to their size and density, and tumuli according to their size, inter-tumulus distance and density. Ailinella mirabilis is the first cestode described from G. maculatus and the second triaenophorid species recorded from a South American freshwater fish.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

694. Air ejector with a diffuser that includes boundary layer suction

Creator:
Dvořák, Václav
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
air ejector, diffuser, and boundary layer suction
Language:
English
Description:
The article deals with axial-symmetric subsonic air-to air ejector with a diffuser adapted for boundary layer suction. The diffuser, which is placed after the mixing chamber of the ejector, has a high divergence angle and is therefore inefficient. To increase efficiency, the diffuser is equipped with a slot enabling boundary layer suction. The effect of boundary layer suction on the airflow in the ejector was measured, as were the static pressure distribution on the mixing chamber wall and ejector characteristics. Both diffuser and ejector efficiency were calculated. Although the efficiency of the diffuser was increased, the efficiency of the ejector itself remained low. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

695. Air lime mortars with incorporation of sepiolite and synthetic zeolite pellets

Creator:
Andrejkovičová, Slávka, Ferraz, Eduardo, Velosa, Ana L., Silva, António S., and Rocha, Fernando
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, vápno, malty, syntetické zeolity, lime, mortar, synthetic zeolites, sepiolite, synthetic zeolite pellets, 7, and 551
Language:
English
Description:
The requirements of conservators who take care of historical monuments are that the materials for rehabilitation of old renders should have a composition as similar to the historical materials as possible and should provide improvement in durability. Fine and coarse sepiolite and synthetic zeolite pellets were chosen as additives in the development of lime mortars for conservation work, due to their unique adsorption properties providing water to the mortar system and acting as water reservoirs in conditions of low humidity. Flexural and compressive strength and the dynamic modulus of elasticity were studied at 28, 90 and 180 days of curing. Addition of both fine and coarse sepiolite and zeolite pellets caused improvement of mechanical strength of mortars, clearly evident at later ages of curing. Elasticity modulus ranged from 2.3 GPa to 3.6 GPa relating to a high deformation capability of mortars and confirming their suitability for use in conservation work., Slávka Andrejkovičová, Eduardo Ferraz, Ana L. Velosa, António S. Silva and Fernando Rocha., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

696. Air-pressure, vocal fold vibration and acoustic characteristics of phonation during vocal exercising. Part 1. Measurement in vivo

Creator:
Radolf, Vojtěch, Laukkanen, Anne-Maria, Horáček, Jaromír, and Liu, Dong
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
biomechanics of voice, subglottal, oral and transglottal pressure, electroglottography, and phonation into tubes
Language:
English
Description:
The study investigates differences between three most widely used methods in voice training and therapy: Phonation into a resonance tube with the outer end in the air or submerged 2-10 cm in water (‘water resistance therapy‘ with bubbling effect), and phonation into a very thin straw. One female speech trainer served as subejct. Acoustic and electroglottographic (EGG) signals, and both mean and dynamic air pressures in the mouth cavity were registered for repetitions of [pu:pu], and for phonation into the tubes, while the outer end was randomly shuttered in order to get an estimate of subglottic pressure. Soft and normal phonations were recorded. Phonation threshold decreased with tube in air, suggesting that increased input reactance assists small amplitude oscillation of the vocal folds. Oral pressure (Poral) increased with increasing impedance offered by the tube and straw, most when the tube was 10 cm in water. In most cases subglottic pressure (Psub) increased relatively more than Poral, so that tranglottic pressure (Ptrans) was higher in the exercises compared to vowel. Contact quotient (CQ) from EGG increased, which may be due to increased Ptrans. In tube 10 cm in water Ptrans decreased and CQ increased suggesting increased adduction as compensation. Exercises that increase oral eir-pressure offer a possibility to train flottal and respiratory adjustments under the influence of increased flow resistance which may prevent excessively strong vocal fold collisions. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

697. Air-pressure, vocal folds vibration and acoustic characteristics of phonation during vocal exercising. Part 2. Measurement on a physical model

Creator:
Horáček, Jaromír, Radolf, Vojtěch, Bula, Vítězslav, and Laukkanen, Anne-Maria
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
biomechanics of voice, subglottal, oral and transglottal pressure, and flow resistance
Language:
English
Description:
The contribution aims to provide material that can be used in development of more realistic physical as well as theoretical models of voice production. The experimental set-up methodology and the results of measurement of airflow rate, subglottal, oral and generated acoustic air pressures are presented together with the simultaneously measured flow-induced vibrations of a vocal folds replica, made of soft silicon rubber, and recorded by a high speed camera. The data were measured during ‘soft‘ phonation onset, given by the phonation threshold airflow rate, and during ‘normal‘ phonation for the airflow rate of about three times higher. A model of the human vocal tract in the position for production of vowel [u:] was used, and the flow resistance was raised by phonating into a glass resonance tube either in the air or having the other end of the tube submerged under water, and by phonating into a narrow straws. The results for the pressures presented in time and frequency domain are comparable with the physiological ranges and limits measured in humans for ordinary phonation and for production of vocal exercises used in voice therapy. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

698. Aircraft engine lubricating oil monitoring by process neural network

Creator:
Gang, Ding and Shisheng, Zhong
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Lubricating oil monitoring, process neural network (PNN), Time series prediction, aircraft engine condition monitoring, and orthogonal basis function
Language:
English
Description:
The aircraft engine lubricating oil monitoring is essential in terms of the flight safety and also for reduction of the maintenance cost. The concentration of metal elements in the lubricating oil includes a large amount of information about the health condition of the aircraft engine. By monitoring the lubricating oil, maintenance engineers can judge the performance deterioration of the aircraft engine and can find the latent mechanical faults in the aircraft engine in advance. But it is difficult for traditional methods to predict the tendency of the mental elements concentration in the lubricating oil. In this paper, a time series prediction method based on process neural network (PNN) is proposed to solve this problem. The inputs and the connection weights of the PNN are time-varied functions. A corresponding learning algorithm is developed. To simplify the learning algorithm, a set of appropriate orthogonal basis functions are introduced to expand the input functions and the connection weight functions of the PNN. The effectiveness of the proposed method is proved by the Mackey-Glass time series prediction. Finally, the proposed method is utilized to predict the Fe concentration in the aircraft engine lubricating oil monitoring, and the test results indicate that the proposed model seems to perform well and appears suitable for using as a predictive maintenance tool.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

699. Airflow limitation is accompanied by diaphragm dysfunction

Creator:
Hellebrandová, L., Chlumský, J., Vostatek, P., Novák, D., Zuzana Ryznarová, and Bunc, V.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, bránice, diaphragm, asthma bronchiale, pulmonary function, 14, and 612
Language:
English
Description:
Chronic airflow limitation, caused by chronic obstructive pulmonary disease (COPD) or by asthma, is believed to change the shape and the position of the diaphragm due to an increase in lung volume. We have made a comparison of magnetic resonance imaging (MRI) of diaphragm in supine position with pulmonary functions, respiratory muscle function and exercise tolerance. We have studied the differences between patients with COPD, patients with asthma, and healthy subjects. Most interestingly we found the lung hyperinflation leads to the changes in diaphragmatic excursions during the breathing cycle, seen in the differences between the maxim al expiratory diaphragm position (DPex) in patients with COPD and control group (p=0.0016) . The magnitude of the diaphragmatic dysfunction was significantly related to the airflow limitation expressed by the ratio of forced expiratory volume in 1 s to slow vital capacity (FEV 1 /SVC) , (%, p=0.0007); to the lung hyperinflation expressed as the ratio of the residual volume to total lung capacity (RV/TLC), (%, p=0.0018) and the extent of tidal volume constrain expressed as maximal tidal volume (V Tmax ), ([l], p=0 .0002); and the ratio of tidal volume to slow vital capacity (VT/SVC), (p=0.0038) during submaximal exercise. These results suggest that diaphragmatic movement fails to contribute sufficiently to the change in lung volume in emphysema. Tests of respiratory muscle function were related to the position of the diaphragm in deep expiration, e.g. neuromuscular coupling (P 0.1 /VT) (p=0.0232). The results have shown that the lung volumes determine the position of the diaphragm and function of the respiratory muscles. Chronic airflow limitation seems to change the position of the diaphragm, which thereafter influences inspiratory muscle function and exercise tolerance. There is an apparent relationship between the position of the diaphragm and the pulmonary functions and exercise tolerance., L. Hellebrandová, J. Chlumský, P. Vostatek, D. Novák, Z. Rýznarová, V. Bunc., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

700. Akcelerácia častíc laserom indukovanou plazmou

Creator:
Viskup, Richard and Lukáč, Peter
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
lasery, plazma (fyzika), lasers, plasma (ionized gases), 6, and 53
Language:
Czech and English
Description:
From the very first experiments performed with high intensity laser pulse interaction with matter it has been clear that laser produced plasma is a rich source of emitting high energetic particles and electromagnetic radiation in a broad spectral range. In this article a basic phenomenon of nonlinear processes of high intensity laser pulse interaction and related acceleration of particles in laser induced thermal plasma are outlined. possible applications of ultra-short mono-energetic electron beams (with divergence and small energy spread) which are generated during this interaction are also discussed., Už od vykonania prvých experimentov použitím intenzívneho laserového žiarenia s hmotou bolo zrejmé, že laserom indukovaná plazma je bohatým zdrojom vysokoenergetických častíc a elektromagnetického žiarenia v širokej škále spektrálnych oblastí. V článku je bližšie uvedená problematika nelineárnych javov počas vysokointenzívnych laserových interakcií a s tým súvisiacu aj akceleráciu častíc v laserom indukovanej termálnej plazme. Taktiež sú uvedené aj potencionálne možné aplikácie vysokoenergetických elektrónových zväzkov, které sú generované pri týchto interakciách a dosahujú rýchlosti blízke rýchlosti svetla., Richard Viskup, Peter Lukáč., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

Limit your search

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

Show values starting with
more »

View distribution

Current results range from 1921 to 2022

View larger »