Respiratory dynamic

The potential for liquid aerosols or finely divided powders to be inhaled will be determined by their particle size. Deposition patterns for dusts will depend not only on the particle size of the dust but also the hygroscopicity, electrostatic properties and shape of the particles, and the respiratory dynamics of the individual. Thus, it is only possible to make very general statements about sites of... 

During the period in which Horgan and Lange were carrying on their studies, Clegg (37) presented a careful study of respiratory control which followed a more basic control approach than that used previously. The schematic representation of the system is shown in Figure 4. This work, which is seldom referenced, represented one of the first attempts at specifying the relative importance of the peripheral and central chemoreceptors to respiratory dynamics and stability. The model exhibited realistic transient and steady-state behavior under various conditions. 

D. Hoyer, K. Schmidt, R. Bauer, U. Zwiener, M. Kohler, B. Luthke, and M. Eiselt, Nonlinear analysis of heart rate and respiratory dynamics, IEEE Eng. Med. Biol. Mag. 16 31-39 (1997). 

The modem NRDS therapy includes the use of different native or synthetic exogenous surfactants (ES), like the native surfactant Curosurf . ES function as analogues for normal human AS. The main characteristics of these preparations are their strong surface activity upon spreading at the air/water interface and their specific respiratory dynamic mechanical and physical characteristics during alveolar contraction and expansion [8-12]. 

Marini JJ, Crooke PS. A general mathematical model for respiratory dynamics relevant to the clinical setting. Am Rev Respir Dis 1993 147 14-24. 

Conti, M.L., Che, M.M., Boylan, M., et al., 2009. Acute microinstillation inhalation exposure to sarin induces changes in respiratory dynamics and functions in guinea pigs. Int. J. Toxicol. 28, 436-447. 

Rezk, P.E., Graham, J.R., Moran, T.S., et al., 2007. Acute toxic effects of nerve agent VX on respiratory dynamics and functions following microinstillation inhalation exposure in guinea pigs. Inhal. Toxicol. 19, 291-302. 

TRIR methods have also found utility in the elucidation of reaction mechanisms involved in biological systems, most notably photosynthetic and respiratory proteins. In addition, TRIR spectroscopy has also been used to enhance our understanding of the dynamics of protein folding processes. ... 

Type SR-1 compounds include soluble or reactive gases and vapors which are expected to be taken up by the respiratory tract tissues and may deposit in any or all of the regions of the respiratory tract, depending on the dynamics of the airways and properties of the surface mucous and airway tissues, as well as the solubility and reactivity of the compound. 

Vachon L, Fitzerald MX, Solliday NH, Gould IA, Gaensler EA. Singledose effect of marijuana smoke bronchial dynamics and respiratory-center sensitivity in normal subjects. N Engl J Med 1973 288 985-989. 

The ICRP Task Group on Lung Dynamics (ICRP, 1966) also reviewed the available literature and developed a model to describe the clearance of materials from the respiratory tract to the gastrointestinal... 

Figure 7. The dynamic patterns of S02 and NOx emissions and the rates of respiratory morbidity over a period of1991-1996 in Armyansk City, Ukraine.

Several animal studies listed in Table 5-5 describe effects at concentrations below those causing incapacitation or unconsciousness. These 30-min studies are as follows monkey, 60 ppm (slight CNS effects) (Purser 1984) rat, 55 ppm (changes in lung dynamics and phospholipids) (Bhattacharya et al. 1984) and mouse, 63 ppm (respiratory depression of 50%) (Matijak-Schaper and Alarie 1982). From the description given by Matijak-Schaper and Alarie (1982), the concentration of 63 ppm for 30 min appears to be the... 

Pulmonary dynamics, the dimension and geometry of the respiratory tract and the structure of the lungs, together with the solubility and chemical reactivity of the inhalants greatly influence the magnitude of penetration, retention, and absorption of inhaled gases, vapors (Dahl, 1990), and aerosols (Raabe, 1982 Phalen, 1984). The quantity of an inhalant effectively retained in the pulmonary system constitutes the inhaled dose that causes pharmacotoxic responses. 

Task Group on Lung Dynamics. (1966). Deposition and retention models for internal dosimetry of the human respiratory tract. Health Phys. 12 173-207. 

The dynamic properties of the mucus fluid, serous fluid, and epithelial layers of the respiratory tract are important for the transport, absorption, and desorption of reactive gases. The cilia beat at a fairly constant frequency within the stationary serous layer and cause the outer mucus layer to move up the respiratory tract. Clearance of deposited particles and absorbed gases in the ciliated tracheobronchial tree depends partly on the movement of this mucus layer. 

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