Kinematic and Passive Resistive Properties of Human Elbow Complex

1987 ◽  
Vol 109 (4) ◽  
pp. 318-323 ◽  
Author(s):  
Ali Erkan Engin ◽  
Shuenn-Muh Chen
Keyword(s):  
Mathematical Models ◽  
Data Base ◽  
Human Body ◽  
Statistical Data ◽  
Normal Male ◽  
Angular Range ◽  
Elbow Extension ◽  
Expansion Form ◽  
Motion Studies ◽  
Male Subjects

In recent years, owing to their versatility and reduced cost of operation, multisegmented mathematical models of the total human body have gained increased attention in gross biodynamic motion studies. This, in turn, has stimulated the need for a proper biomechanical data base for the major human articulating joints. The lack of such a database for the humero-elbow complex is the impetus for this study. The total angular range of motion permitted by the complex and the passive resistive properties beyond the full elbow extension were studied. Results obtained on ten normal male subjects were utilized to establish a statistical data base for the humero-elbow complex. Results are also expressed in functional expansion form suitable for incorporation into the existing multisegmented models.

Statistical Data Base for the Biomechanical Properties of the Human Shoulder Complex—I: Kinematics of the Shoulder Complex

1986 ◽  
Vol 108 (3) ◽  
pp. 215-221 ◽  
Author(s):  
A. E. Engin ◽  
S.-M. Chen
Keyword(s):  
Data Collection ◽  
Data Base ◽  
Human Body ◽  
Statistical Data ◽  
Biomechanical Properties ◽  
Senior Author ◽  
Male Population ◽  
Shoulder Region ◽  
Expansion Form ◽  
Shoulder Complex

In the last two decades, several multi-segmented mathematical models of the total-human-body have appeared in the literature. While these models can handle very sophisticated load-motion situations, their effectiveness depends heavily on the proper biomechanical description and simulation of the major articulating joints of the human body. Among these joints, the most complicated and the least successfully modeled one has been the shoulder complex mainly due to the lack of an appropriate biomechanical data base as well as the anatomical complexity of the shoulder region. In 1984, the senior author and his associates proposed a new kinematic data collection methodology by means of sonic emitters and associated data analysis technique. Based on this data collection methodology, Part I of this paper establishes a statistical data base for the shoulder complex sinus of the male population of ages 18–32. Estimates for the population mean and standard deviation as well as their confidence intervals are presented. The results are expressed in functional expansion form relative to a locally defined joint axis system as well as relative to the torso-fixed coordinate system in the form of globographic representation.

Frequency, Intensity, and Target Matching Effects on Photoglottographic Measures of Open Quotient and Speed Quotient

1990 ◽  
Vol 33 (1) ◽  
pp. 45-50 ◽  
Author(s):  
David G. Hanson ◽  
Bruce R. Gerratt ◽  
Gerald S. Berke
Keyword(s):  
Fundamental Frequency ◽  
Significant Interaction ◽  
Normal Male ◽  
Similar Frequency ◽  
Intensity Changes ◽  
Male Subjects ◽  
Target Matching ◽  
Frequency Intensity

Measurements of Open Quotient (OQ) and Speed Quotient (SQ) were made from photoglottographic signals of normal male subjects during phonation. Samples were obtained at spontaneous levels of fundamental frequency and intensity, and at nine specified frequency/intensity combinations. OQ increased with fundamental frequency. OQ change was not significant for change in intensity and there was no significant interaction between frequency and intensity. Changes in SQ with variations of frequency and intensity were not significant. However, SQ did increase significantly when spontaneous phonation was compared to target matching phonation at similar frequency/intensity. Changes in both OQ and SQ across comfortable frequency and intensity ranges were relatively small in comparison to changes in OQ and SQ reported for pathological phonation.

MECHANISMS OF ADAPTATION OF THE LEFT VENTRICLE TO MUSCULAR EXERCISE

PEDIATRICS ◽  
1963 ◽  
Vol 32 (4) ◽  
pp. 660-670
Author(s):  
Jere H. Mitchell
Keyword(s):  
Cardiac Output ◽  
Left Ventricle ◽  
Stroke Volume ◽  
Pulse Rate ◽  
Individual Factors ◽  
Normal Male ◽  
Oxygen Intake ◽  
Mechanisms Of Adaptation ◽  
Male Subjects ◽  
Oxygen Difference

THE mechanisms of adaptation of the left ventricle to the demands of muscular exercise have intrigued cardiovascular physiologists for many years. Although highly complex, these adaptive mechanisms are more and more susceptible to analysis and quantification. In this presentation I will attempt to identify some of the individual factors which appear to be important in the response of the left ventricle to exercise, beginning with data obtained from experiments on conscious normal male subjects and proceeding to experiments performed on dog preparations in which individual factors were controlled and analyzed. The changes in oxygen intake, cardiac output, estimated arteriovenous oxygen difference, pulse rate and estimated mean stroke volume were determined in 15 normal male subjects during rest in the standing position and during treadmill exercise at the maximal oxygen intake level. Oxygen intake was obtained from the volume and composition of expired air, cardiac output by the dye dilution technique, and pulse rate from the electrocardiogram. Estimated arteriovenous oxygen difference was obtained by dividing the oxygen intake by the cardiac output (Fick principle) and estimated mean stroke volume by dividing the cardiac output by the heart rate. The data are shown in Figure 1. Oxygen intake increased from a mean value of 0.34 at rest to a maximal value of 3.22 L./min. The corresponding mean values for cardiac output were 5.4 and 23.4 L./min. and for arteriovenous oxygen difference were 6.5 and 14.3 ml./100 ml. Thus, as oxygen intake increased 9.5 times, the cardiac output increased 4.3 times and the arterio venous oxygen difference 2.2 times.

scholarly journals Kinetics and stoichiometry of Na-dependent Li transport in human red blood cells.

1978 ◽  
Vol 72 (2) ◽  
pp. 249-265 ◽  
Author(s):  
B Sarkadi ◽  
J K Alifimoff ◽  
R B Gunn ◽  
D C Tosteson
Keyword(s):  
Transport System ◽  
Red Cells ◽  
Normal Male ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Human Red Blood Cells ◽  
Na Efflux ◽  
Tightly Coupled ◽  
Male Subjects ◽  
Human Red Cells

This paper describes the kinetics and stoichiometry of a tightly coupled Na-Li exchange transport system in human red cells. The system is inhibited by phloretin and furosemide but not by ouabain. Li influx by this system increases and saturates with increasing concentrations of external Li and internal Na and is inhibited competitively by external Na. Comparable functions relate Li efflux and Na efflux to internal and external Li and Na concentrations. Analysis of these relations yields the following values for the ion concentrations required to half-maximally activate the transport system: internal Na and Li 9.0 and 0.5 mM, respectively, external Na and Li 25 and 1.5 mM, respectively. The system performs a 1:1 exchange of Na and Li moving in opposite directions across the red cell membrane. We found no evidence for a simultaneous transport of more than one Na and Li by the system. The maximum transport rate of Na-dependent Li transport varied between 0.1 and 0.37 mmol/(liter of cells X h) in the red cells of the five normal male subjects studied. No significant variations between individual subjects were observed for bicarbonate-stimulated Li transport and for the residual Li fluxes which occur in the absence of bicarbonate and in the presence of ouabain plus phloretin.

scholarly journals Mathematical models as practical tool for road fatalities forecasts on road network in regions

2018 ◽  
Vol 231 ◽  
pp. 01018 ◽  
Author(s):  
Joanna Wachnicka
Keyword(s):  
Mathematical Models ◽  
Traffic Safety ◽  
Road Safety ◽  
Regression Models ◽  
Road Network ◽  
Statistical Data ◽  
Safety Management ◽  
National Data ◽  
Local Characteristics ◽  
Practical Tool

The analysis of national data on the number of deaths showed that in Poland from 2010 to 2016 it was possible to reduce the number of fatalities by about 22%. The tendency of changes in the number of fatalities, however, is not homogeneous. When data of individual voivodships is analyzed, the situation is different. The largest reduction in fatalities in the analyzed period of time concerned voivodship Świętokrzyskie, where there was more than 45% drop in the number of fatalities. The following voivodships: Łódzkie, Lubelskie and Podkarpackie recorded a decrease in over 30% of fatalities. Unfortunately, at the end of the classification there were four voivodships with a fall below 8%, and what is disturbing voivodship Lubuskie recorded a nearly 5% increase in the number of fatalities. The current traffic safety management at the level of voivodships is often the implementation of central recommendations, which, as results from the analysis of statistical data, are not equally effective in every province. Therefore, models for forecasting changes in road safety are required. Taking into account local characteristics and implemented actions can be used to manage security more effectively at the regional level. This paper presents examples of the use of mathematical models to predict the number of fatalities in individual voivodships depending on the adopted action scenarios. Regression models were developed, taking into account demographic, infrastructural, economic and automotive factors. It turned out that in individual voivodships, various factors affect the level of road safety on roads differently. Therefore, an individual approach to each voivodship is important in order to reliably forecast the level of security.

scholarly journals Comparison of the Effects of Intravenous Papaverine Hydrochloride and Oral Pavabid HP Capsulets on Regional Cerebral Blood Flow in Normal Individuals

1983 ◽  
Vol 3 (4) ◽  
pp. 442-447 ◽  
Author(s):  
Lawrence C. McHenry ◽  
David A. Stump ◽  
George Howard ◽  
Thomas T. Novack ◽  
Don H. Bivins ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Normal Subjects ◽  
Normal Male ◽  
Regional Cerebral Blood ◽  
Normal Individuals ◽  
Left And Right ◽  
Male Subjects ◽  
Papaverine Hydrochloride

A single-blind study was conducted in 13 right-handed normal male subjects to compare the effects of oral and i.v. papaverine on regional cerebral blood flow (rCBF). Six xenon-133 inhalation rCBF measurements were performed on each subject; three tests—baseline, placebo, and drug evaluations—were carried out on each of two separate days. The oral and i.v. drugs were randomized for first-day administration. rCBF, measured as flow gray (FG), increased significantly (p ≤ 0.001) from baseline with both drug forms. Increases of 10.53% and 13.94% (left and right hemispheres, respectively) were demonstrated 90 min after a single 600-mg dose of oral papaverine. Increases of 5.09% and 8.69%, respectively, were recorded immediately after a single 100-mg dose of i. v. papaverine. FG also increased significantly (p ≤ 0.001) for both drug forms when compared to that of placebo. Placebo produced only a slight increase (not significant) with both the oral and i.v. groups. The data show that both oral and i.v. papaverine are equally effective in increasing rCBF in normal subjects.

Sweat suppression by forced breathing in man

1965 ◽  
Vol 20 (1) ◽  
pp. 134-136 ◽  
Author(s):  
Roy E. Albert
Keyword(s):  
Carbon Dioxide ◽  
Sweat Rate ◽  
Respiratory Alkalosis ◽  
Normal Male ◽  
Excess Carbon ◽  
Air Breathing ◽  
Thermal Sweating ◽  
Forced Air ◽  
Forced Breathing ◽  
Male Subjects

Thermal sweating from the forehead was suppressed by forced air breathing in two normal male subjects. The decreased sweat rate was associated with symptoms of respiratory alkalosis. This sweat suppression was blocked by the introduction of excess carbon dioxide into the respired gas. sweating and hyperventilation; hyperventilation and sweating; respiratory alkalosis and sweating Submitted on February 7, 1964

Relative Bioavailabilities of Natural and Synthetic Vitamin E Formulations Containing Mixed Tocopherols in Human Subjects

1999 ◽  
Vol 69 (2) ◽  
pp. 92-95 ◽  
Author(s):  
Chopra ◽  
Bhagavan
Keyword(s):  
Vitamin E ◽  
Animal Models ◽  
Human Subjects ◽  
Alpha Tocopherol ◽  
Tocopheryl Acetate ◽  
Normal Male ◽  
Gamma Tocopherol ◽  
Synthetic Vitamin ◽  
Male Subjects ◽  
Natural And Synthetic

There are several reports in the literature on the relative bioavailabilities of RRR (natural) vs. all-rac (synthetic) forms of vitamin E in humans and animal models but none on the bioavailability of alpha-tocopherol in mixed vitamin E formulations. In the present study we examined the bioavailability of alpha-tocopherol in a typical commercially available product containing mixed tocopherols. We also tested a formulation containing all-rac-alpha-tocopherol with mixed tocopherols for purposes of comparison along with straight RRR-and all-rac-alpha-tocopheryl acetate as reference products. Normal male subjects were given one of the four formulations of vitamin E (800 IU per day in softgel capsule form for 10 days): 1. All-rac-alpha-tocopheryl acetate, 2. RRR-alpha-tocopheryl acetate, 3. RRR-alpha-tocopherol with mixed tocopherols, and 4. all-rac-alpha-tocopherol with mixed tocopherols. Both serum alpha- and gamma-tocopherols were determined by HPLC at baseline, and at days 2, 4, 7 and 10. The values for alpha- at baseline and 10 days were 0.80, 0.80, 0.80 & 0.79 mg/dl and 1.67, 1.72, 1.76 & 1.62 mg/dl. The values for gamma- were 0.28, 0.29, 0.30 & 0.29 mg/dl and 0.11, 0.08, 0.10 & 0.10 mg/dl. Thus the data show that a) the bioavailability of RRR-and all-rac-alpha-tocopherols is not affected by other tocopherols, and b) both RRR-and all-rac-alpha-tocopherol (free or esterified) significantly suppress the serum gamma tocopherol to the same extent. Furthermore, since there was no difference in the serum values of alpha-tocopherol between RRR-and all-rac-vitamin E given the same dose as IUs, the data also support the currently accepted ratio of 1.36 for the biopotency of RRR- vs. all-rac-alpha-tocopheryl acetate.

Increase in Prostaglandins during Converting Enzyme Inhibition

1980 ◽  
Vol 59 (s6) ◽  
pp. 133s-135s ◽  
Author(s):  
S. L. Swartz ◽  
G. H. Williams ◽  
N. K. Hollenberg ◽  
F. R. Crantz ◽  
L. Levine ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Plasma Concentration ◽  
Sodium Intake ◽  
Thromboxane A2 ◽  
Normal Male ◽  
Converting Enzyme ◽  
Low Sodium ◽  
Converting Enzyme Inhibition ◽  
Male Subjects ◽  
Hypotensive Response

1. Because changes in the plasma concentration of angiotensin II and bradykinin appear inadequate to account completely for the hypotensive response to captopril, we measured changes in plasma prostaglandins in response to increasing doses of captopril in nine supine normal male subjects studied on both a high (200 mol/l) and low (10 mol/l) sodium intake. 2. On both the high and low sodium diets, captopril induced significant (P<0.01) increments in the 13,14-dihydro-15-keto metabolite of the vasodilatory prostaglandin E2, which correlated significantly with the fall in blood pressure (P<0.0001). 3. No significant changes were noted in the plasma levels of 6-keto-prostaglandins F1α or thromboxane B2, the stable products of prostacyclin and thromboxane A2 respectively.

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