Pressure-Flow Relationship at the Entrance of the Pulmonary Circulatory System of Man

Author(s):  
G. R. Fricke ◽  
H. Mattern
Irriga ◽  
2003 ◽  
Vol 8 (1) ◽  
pp. 63-68 ◽  
Author(s):  
Marco Antonio Fonseca Conceição ◽  
Rubens Duarte Coelho

RELAÇÃO VAZÃO x PRESSÃO EM MICROASPERSORES DAN 2001 SOB CONDIÇÃO ADVERSA DE OPERAÇÃO  Marco Antônio Fonseca ConceiçãoEmbrapa Uva e Vinho, Estação Experimental de Jales, Jales, SP. CP 241. CEP 15700-000.E-mail: [email protected] Duarte CoelhoDepartamento de Engenharia Rural, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba, SP. CP 09, CEP 13418-900.E-mail: [email protected]  1 RESUMO  Alguns microaspersores possuem membranas que regulam a sua pressão de operação, mantendo a vazão praticamente estável dentro de uma faixa de pressão na rede hidráulica. Operadores de irrigação no campo, muitas vezes com baixo nível de instrução e sem orientação profissional qualificada, visando reduzir problemas de entupimento ou para diminuir o tempo de irrigação, costumam retirar as membranas autocompensantes para aumentar a vazão do emissores, o que pode comprometer o desempenho hidráulico do sistema. Para avaliar o efeito da retirada da membrana  sobre as vazões dos microaspersores, no presente trabalho determinou-se as relações entre pressão e vazão para sete bocais do microaspersor DAN 2001, operando na ausência da membrana autocompensante. As curvas pressão-vazão sem as membranas autocompensantes apresentaram comportamento potencial com expoentes variando entre 0,58 e 0,64. As vazões dos microaspersores sem as membranas aumentaram de forma inversamente proporcional aos diâmetros dos emissores, quando comparadas às vazões nominais com as membranas.  UNITERMOS: Hidráulica, irrigação, microaspersão.  CONCEIÇÃO, M.A.F.; COELHO, R.D. FLOW X PRESSURE RELATIONSHIP FOR DAN 2001 MICROSPRINKLERS UNDER ADVERSE CONDITION  2 ABSTRACT  Many types of microsprinklers have a self-compensating membrane to regulate their pressure, keeping a stable flow. Many producers usually take the membranes off to reduce clogging problems  or irrigation time. This procedure could endanger the system hydraulic performance. To evaluate the effect of taking off the self-compensating membrane from microsprinklers it was determined, in the present work, the pressure-flow relationship for seven Dan 2001 microsprinkler nozzles operating without the membrane. The pressure-flow curves presented a potential behavior with the exponents varying from 0.58 to 0.64. Microsprinkler flows without the membranes increased inversely proportional to the emitter diameters, comparing to the nominal flows using the membranes.  KEYWORDS: Hydraulic, irrigation, microsprinkler.


Author(s):  
Meri L. Andreassen ◽  
Bonnie E. Smith ◽  
Thomas W. Guyette

Pressure-flow data are often used to provide information about the adequacy of velopharyngeal valving for speech. However, there is limited information available concerning simultaneous pressure-flow measurements for oral and nasal sound segments produced by normal speakers. This study provides normative pressure, flow, and velopharyngeal orifice area measurements for selected oral and nasal sound segments produced by 10 male and 10 female adult speakers. An aerodynamic categorization scheme of velopharyngeal function, including one typical category and three atypical categories (open, closed, and mixed) is proposed.


Author(s):  
G. I. Tikhonova ◽  
M. S. Bryleva ◽  
T. Yu. Gorchakova

Standardized mortality rates of the male population aged 15-59 in Monchegorsk, where the Kola mining and metallurgical company is located, were higher relative to the Murmansk region and Russia: from diseases of the circulatory system by 34.8% and 52.1%, respectively, from malignant neoplasms by 26.3% and 19.4%, from diseases of the digestive system by 59.0% and 36.3%.


Author(s):  
Nina M. Meshchakova ◽  
Marina P. Dyakovich ◽  
Salim F. Shayakhmetov

Introduction.Methanol and its derivatives occupy one of the leading places among the main organic synthesis intermediates in terms of their importance and scale of production. According to experts, by 2027 the global demand for methanol can reach 135 million tons, the annual growth will be about 5.5%. However, there is little information regarding the assessment of working conditions and occupational risks for workers in modern methanol production and its derivatives.The aim of the studyis hygienic assessment of working conditions and the formation of health risks in workers of modern production of methanol and methylamines.Materials and methods.The assessment of the main adverse factors of production is given. When studying the state of health, objective indicators (the results of an in-depth medical examination) and subjective (the results of a quantitative assessment of the risks of the main pathological syndromes associated with health) are considered.Results.According to long-term observations, the concentration of harmful substances in the air of the working area, indicators of labor severity, parameters of physical factors met hygienic requirements, with the exception of industrial noise exceeding the maximum permissible level, as well as labor intensity of 1 degree. The General assessment of working conditions corresponds to the category of harmful 2 degrees (3.2). According to the results of the medical examination and quantitative assessment of the risks of health disorders in workers, the most significant were functional disorders and diseases of the circulatory system. The levels of somatic pathology on the part of the main body systems were significantly higher in apparatchiks compared to the engineering and technical personnel (ETP).Conclusions:In the production of methyl alcohol and methylamines, the main hygienic importance is the impact on workers of the complex of harmful substances of 1-IV hazard classes in low concentrations, increased levels of industrial noise, labor intensity of 1 degree. According to the subjective assessment of health and medical examination, the greatest prevalence of health risks in workers was observed from the circulatory system, and the levels of the revealed somatic pathology were statistically significantly higher in apparatchiks compared with the ETP.


Author(s):  
L. Yu. Orekhova ◽  
A. A. Petrov ◽  
E. S. Loboda ◽  
I. V. Berezkina ◽  
K. V. Shadrina

Relevance. The study of age-related features of microcirculation in periodontal tissues, using non-invasive functional research methods, allows us to develop the optimal range of therapeutic measures, as well as form a “personalized therapeutic case”.Purpose. Study of the functional state of the microvasculature in the tissues of the parodont in individuals of various age groups.Materials and methods. A standard dental examination of 80 patients was carried out, the sample of participants was ranked in 4 groups by age: 1 group – 12 years old, 2 group – 15 years old, 3 group – from 16 to 18 years old, 4 group – from 22 to 24 years old. Hygiene and periodontal indices were determined for all patients, such as papillarymarginal-alveolar (PMA) in the Parma modification, the Mulleman bleeding index in the Cowell modification (SBI), and the simplified Green Vermillion index of oral hygiene (OHI–s), caries intensity indicators for a permanent bite (CPI), as well as ultrasound dopplerography of periodontal tissues using the apparatus "Minimax-Doppler-K".Results. When studying microcirculation in periodontal tissues, distinctive characteristics of linear (Vas) and volumetric (Qas) blood flow rates, as well as indicators of pulsation indices (PI) and peripheral resistance (RI) in people of different age groups were recorded.Conclusions. This study confirms the presence of various hemodynamic indicators of periodontal tissues in the studied groups, which is due to structural features of the circulatory system in age periods.


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