scholarly journals New Mathematical Model for the Surface Area of the Left Ventricle by the Truncated Prolate Spheroid

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
José Sérgio Domingues ◽  
Marcos de Paula Vale ◽  
Carlos Barreira Martinez

The main aim of this study was the formula application of the superficial area of a truncated prolate spheroid (TPS) in Cartesian coordinates in obtaining a cardiac parameter that is not so much discussed in literature, related to the left ventricle (LV) surface area of the human heart, by age and sex. First we obtain a formula for the area of a TPS. Then a simple mathematical model of association of the axes measures of a TPS with the axes of the LV is built. Finally real values of the average dimensions of the humans LV are used to measure surface areas approximations of this heart chamber. As a result, the average superficial area of LV for normal patients is obtained and it is observed that the percentage differences of areas between men and women and their consecutive age groups are constant. A strong linear correlation between the obtained areas and the ventricular volumes normalized by the body areas was observed. The obtained results indicate that the superficial area of the LV, besides enabling a greater knowledge of the geometrical characteristics of the human LV, may be used as one of the normality cardiac verification criteria and be useful for medical and biological applications.

2014 ◽  
Vol 92 (8) ◽  
pp. 707-714 ◽  
Author(s):  
Thomas Wardziak ◽  
Laurent Oxarango ◽  
Sébastien Valette ◽  
Laurent Mahieu-Williame ◽  
Pierre Joly

Magnetic resonance imaging (MRI) based 3D reconstructions were used to derive accurate quantitative data on body volume and functional skin surface areas involved in water transfer in the Palmate Newt (Lissotriton helveticus (Razoumovsky, 1789)). Body surface area can be functionally divided into evaporative surface area that interacts with the atmosphere and controls the transepidermal evaporative water loss (TEWL); ventral surface area in contact with the substratum that controls transepidermal water absorption (TWA); and skin surface area in contact with other skin surfaces when amphibians adopt water-conserving postures. We generated 3D geometries of the newts via volume-rendering by a “segmentation” process carried out using a graph-cuts algorithm and a Web-based interface. The geometries reproduced the two postures adopted by the newts, i.e., an I-shaped posture characterized by a straight body without tail coiling and an S-shaped posture where the body is huddled up with the tail coiling along it. As a guide to the quality of the surface area estimations, we compared measurements of TEWL rates between living newts and their agar replicas (reproducing their two postures) at 20 °C and 60% relative humidity. Whereas the newts did not show any physiological adaptations to restrain evaporation, they expressed an efficient S-shaped posture with a resulting water economy of 22.9%, which is very close to the 23.6% reduction in evaporative surface area measured using 3D analysis.


2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Ahmed Al-Imam ◽  
Zaid Al-Zamili ◽  
Rawan Omar

Background. The patella is the largest sesamoid bone in the body; its three-dimensional complexity necessitates biomechanical perfection. Numerous pathologies occur at the patellofemoral unit which may end in degenerative changes. This study aims to test the presence of statistical correlation between the surface areas of patellar facets and other patellar morphometric parameters. Materials and Methods. Forty dry human patellae were studied. The morphometry of each patella was measured using a digital Vernier Caliper, electronic balance, and image analyses software known as ImageJ. The patellar facetal surface area was correlated with patellar weight, height, width, and thickness. Results. Inferential statistics proved the existence of linear correlation of total facetal surface area and patellar weight, height, width, and thickness. The correlation was strongest for surface area versus patellar weight. The lateral facetal area was found persistently larger than the medial facetal area, the p value was found to be <0.001 (one-tailed t-test) for right patellae, and another significant p value of < 0.001 (one-tailed t-test) was found for left patellae. Conclusion. These data are vital for the restoration of the normal biomechanics of the patellofemoral unit; these are to be consulted during knee surgeries and implant designs and can be of an indispensable anthropometric, interethnic, and biometric value.


Author(s):  
Renata Žumbakytė-Šermukšnienė ◽  
Agnė Slapšinskaitė ◽  
Miglė Baranauskaitė ◽  
Julija Borkytė ◽  
Rasa Sederevičiūtė ◽  
...  

Aortic rupture is known as one of the potential causes of sudden cardiac death in athletes. Nevertheless, adaptation strategies for aortic root dilation in athletes vary. The purpose of this study was to investigate aortic root adaptation to physical workload and to determine if aortic root&rsquo;s and left ventricle sizes are contingent upon the physical workload. Echocardiography was applied to 151 subjects to measure the aortic root at aortic valve annulus (AA) and at sinus of Valsalva (VS). 122 were athletes (41 females and 81 males) and 29 were non-athletes (14 females and 15 males). Of the 41 female athletes, 32 were endurance athletes, and 9 strength athletes. From 81 male athletes, 56 were endurance athletes, and 25 were strength athletes. AA and VS mean values for the body surface area were presented as rAA and rVS. Left ventricle (LV) meaures incuded LV end-diastolic diameter (LVEDD), interventricular septum thickness in diastole (IVSTd), LV posterior wall thickness in diastole (LVPWTd), LV mass (LVM), LV mass index, LV end-diastolic diameter index (LVEDDI). Results indicated that VS was higher in female athletes (28.9&plusmn;2.36mm) than in non-athletes (27.19&plusmn;2.87mm, p=0.03). On the other hand, rAA was higher in strength athletes (12.19&plusmn;1.48mm/m2) than in endurance athletes (11.12&plusmn;0.99mm/m2, p=0.04). Additionally, rVS and rAA were higher in female strength athletes (17.19&plusmn;1.78mm/m2, 12.19&plusmn;1.48mm/m2) than female basketball players (15.49&plusmn;1.08mm/m2, p=0.03, 10.75&plusmn;1.06 mm/m2, p=0.02). Statistically significant positive moderate correlations were found between VS and LVEDD, LVM, IVSTd, LVPWTd, rVS and LVEDDI parameters in all athletes. The diameter of Valsalva sinus was greater in female athletes compared to non-athletes. The rAA mean value for body surface area was greater in female athletes practising strength sports as compared to their counterparts who were practising endurance sports. The diameter of the aortic root at sinuses positively correlated with the LV size in all athletes. Trial was registered at ClinicalTrials.gov Identifier: NCT03656861, September 3, 2018 (retrospectively registered).


2018 ◽  
Vol 23 (3) ◽  
pp. 50
Author(s):  
José Domingues ◽  
Ravel Coelho ◽  
Francielly Bento ◽  
Brenda Almeida ◽  
Ayanne de Castro

The main objective of this article is to determine the existing linear correlation between the real left ventricular volume (RV) from the heart of bovines and the volumes obtained by Teichholz’s mathematical model and the volume of the truncated prolate spheroid (TPS) to identify which model has a higher proximity to the RV. For that, ten silicon rubber molds of the left ventricle (LV) were manufactured, and their real volumes were obtained through Archimedes’ principle, and their linear dimensions were also obtained. These dimensions were used to feed Teichholz’s and the TPS models. It was verified that, for ventricles of lower volume, the models showed relatively close results, and Teichholz’s model was the most accurate one. The TPS method shows a grave accuracy mistake for higher volume ventricles. Besides, both methods showed strong linear correlations with the RV, and both with high significance.


2020 ◽  
Vol 9 (3) ◽  
pp. 49-53
Author(s):  
K. Sh. Sakibaev

The aim of the study is to determine the features of the skin area in Kyrgyz women population in view of their constitutional groups and somatotypes.Material and methods. We studied the physical status of 1028 Kyrgyz women of different age groups – the juvenile age group (n=310), the 1st adulthood age group (n=310), and the 2nd adulthood age group (n=410) living in Osh and its neighborhood applying anthropometric and bioimpedance methods. Statistical data processing was performed by statistical programs Microsoft Excel and the package STATISTICA 6.0. The differences between the two compared values were determined by the Student's criterion and they were considered significant at p<0.05. Results. The performed study revealed the constitutional and somatotypological features of the skin area in the juvenile and both periods of adulthood in the female population. The body surface area is minimal in women of leptosomic group and maximum in megalosomic one. Somatotypological specificity is determined by the minimum value of this indicator in women of asthenic and stenoplastic types and by the maximum value in representatives of the euriplastic tall type. There is the tendency to increase the body skin area from the juvenile to the 2nd period of adulthood, which is typical for women of all somatotypes and constitutional groups. Conclusion. The area of the skin is one of the indicators of human physical development, which has somatotypological specificity in representatives of various constitutional groups of the studied women population. The presented materials on the constitutional and typological features of the women’s physical status in relative norm conditions can serve as one of the bases for further development of a personalized approach in clinical medicine.


2008 ◽  
Vol 295 (2) ◽  
pp. L235-L237 ◽  
Author(s):  
James C. Parker ◽  
Mary I. Townsley

Current emphasis on translational application of genetic models of lung disease has renewed interest in the measurement of the gravimetric filtration coefficient ( Kf) as a means to assess vascular permeability changes in isolated perfused lungs. The Kf is the product of the hydraulic conductivity and the filtration surface area, and is a sensitive measure of vascular fluid permeability when the pulmonary vessels are fully recruited and perfused. We have observed a remarkable consistency of the normalized baseline Kf values between species with widely varying body weights from mice to sheep. Uniformity of Kf values can be attributed to the thin alveolar capillary barrier required for gas exchange and the conserved matching of lung vascular surface area to the oxygen requirements of the body mass. An allometric correlation between the total lung filtration coefficient ( Kf,t) and body weight in several species ( r2 = 1.00) had a slope that was similar to those reported for alveolar and pulmonary capillary surface areas and pulmonary diffusion coefficients determined by morphometric methods in these species. A consistent Kf is dependent on accurately separating the filtration and vascular volume components of lung weight gain, then Kf is a consistent and repeatable index of lung vascular permeability.


Author(s):  
M. Marko ◽  
A. Leith ◽  
D. Parsons

The use of serial sections and computer-based 3-D reconstruction techniques affords an opportunity not only to visualize the shape and distribution of the structures being studied, but also to determine their volumes and surface areas. Up until now, this has been done using serial ultrathin sections.The serial-section approach differs from the stereo logical methods of Weibel in that it is based on the Information from a set of single, complete cells (or organelles) rather than on a random 2-dimensional sampling of a population of cells. Because of this, it can more easily provide absolute values of volume and surface area, especially for highly-complex structures. It also allows study of individual variation among the cells, and study of structures which occur only infrequently.We have developed a system for 3-D reconstruction of objects from stereo-pair electron micrographs of thick specimens.


Author(s):  
Shirazu I. ◽  
Theophilus. A. Sackey ◽  
Elvis K. Tiburu ◽  
Mensah Y. B. ◽  
Forson A.

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.


Author(s):  
A. E. Chernikova ◽  
Yu. P. Potekhina

Introduction. An osteopathic examination determines the rate, the amplitude and the strength of the main rhythms (cardiac, respiratory and cranial). However, there are relatively few studies in the available literature dedicated to the influence of osteopathic correction (OC) on the characteristics of these rhythms.Goal of research — to study the influence of OC on the rate characteristics of various rhythms of the human body.Materials and methods. 88 adult osteopathic patients aged from 18 to 81 years were examined, among them 30 men and 58 women. All patients received general osteopathic examination. The rate of the cranial rhythm (RCR), respiratory rate (RR) heart rate (HR), the mobility of the nervous processes (MNP) and the connective tissue mobility (CTM) were assessed before and after the OC session.Results. Since age varied greatly in the examined group, a correlation analysis of age-related changes of the assessed rhythms was carried out. Only the CTM correlated with age (r=–0,28; p<0,05) in a statistically significant way. The rank dispersion analysis of Kruskal–Wallis also showed statistically significant difference in this indicator in different age groups (p=0,043). With the increase of years, the CTM decreases gradually. After the OC, the CTM, increased in a statistically significant way (p<0,0001). The RCR varied from 5 to 12 cycles/min in the examined group, which corresponded to the norm. After the OC, the RCR has increased in a statistically significant way (p<0,0001), the MNP has also increased (p<0,0001). The initial heart rate in the subjects varied from 56 to 94 beats/min, and in 15 % it exceeded the norm. After the OC the heart rate corresponded to the norm in all patients. The heart rate and the respiratory rate significantly decreased after the OC (р<0,0001).Conclusion. The described biorhythm changes after the OC session may be indicative of the improvement of the nervous regulation, of the normalization of the autonomic balance, of the improvement of the biomechanical properties of body tissues and of the increase of their mobility. The assessed parameters can be measured quickly without any additional equipment and can be used in order to study the results of the OC.


2019 ◽  
Vol 53 (4) ◽  
pp. 325-334
Author(s):  
V. N. Peskov ◽  
N. A. Petrenko ◽  
V. Yu. Reminnyi

Abstract We study size-at-age and sexual variability of morphometric characteristics of the marsh frog. According to the size of the body, males were divided into three size-age groups (juvenis, subadultus, adultus), females — into four groups (juvenis, subadultus, adultus, adultus-I). We found that the chronological age of frogs (skeletochronology) does not always correspond to their biological age (size and proportions of the body). We noted that the semi-adult males are reliably larger than females by mean values of 26 studied morphometric characters. Males and females of “adultus” group do not differ by linear body size, significant differences were found in body proportions (7 characters). For the females of “adultus-I” group, the mean values of 26 characters are significantly larger than for “adultus” males. The results of our study showed that with the age of the marsh frog, the level of exhibition, directionality and structure of morphometric sex differences changes.


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