scholarly journals Features of transcutaneous penetration of lead into the human body

2021 ◽  
Vol 100 (1) ◽  
pp. 55-59
Author(s):  
Nikolay A. Kashuba

Introduction. One of the features of lead is its high ability to disintegrate and significantly contaminate the environment. The contamination of hands or the whole body with lead creates a high probability of penetrating micro- and nanoparticles through the skin into the body. Nowadays, this process is not sufficiently studied. There is evidence that inorganic compounds or metallic particles of lead can penetrate through the skin into a human body. Material and methods. centrifuge 10000 rpm, laser emitter (wavelength 625-740 nm), optical microscope, voltampermetric analyzer ABA-2, Analysette 12 Dyna Sizer, magnetic stirrer, distiller, Na2S solution. The studies were conducted in 2017-2018 among the workers of battery sections of technical service stations in Ternopol - 17 people. The research results were processed by the statistical package SPSS 19. Results. The process of mechanical contamination by the skin with lead, rejection of micro particles from the surface of lead, and, to a lesser extent, ultrafine nanoparticles, which can penetrate the sweat glands, was established to occur. The studies have shown in the washings from the palms particles’ skin are detected mainly in the size of 1 μm - 100 nm. In the process of finding the particles of lead in the sweat glands, their length decreases to Nanoscale, allowing them freely entering the body. The decrease in particle size in the sweat glands occurs due to the formation of soluble lead compounds. Presumably, the main chemical contributing to this process is lactic acid. With increasing exposure, the size of lead particles in the sweat glands decreases. Intensive cleaning of the skin surface by mechanical methods, and detergents, followed by contamination with lead, promotes the penetration of lead particles into the sweat glands and its further spread in the body. The intense physical activity was established to contribute to a decrease in particle size, which suggests chemical interaction of lead with lactic acid and the formation of soluble lead lactate. The assumption is confirmed by studies of the composition of sweat, which is detected lead lactate. Conclusion. The lead ability to penetrating a human body transcutaneously in the form of nanoparticles and soluble compounds has been proven. Intense physical activity facilitates the penetration of lead into the body.

2019 ◽  
Vol 98 (7) ◽  
pp. 761-765 ◽  
Author(s):  
N. I. Prokhorov ◽  
V. I. Dontsov ◽  
Vyacheslav N. Krutko ◽  
T. M. Khodykina

The widespread formation of unfavorable environmental, the swiftness of modern life with large information and psycho-emotional loads and extremely natural and climatic cataclysms, as well as harmful addictions and wrong way of life of modern human, lead to the development of stress and disruption of the mechanisms of adaptation of the human body and its accelerated wear. This stimulates the development of research on the creation of new methods of integrated assessment of health and quantitative assessment of the aging processes of the body systems and the whole body, as well as the possibilities of new methods of risk assessment of climatic and environmentally related pathological and age-related diseases. The aim of the work was to consider the methodology of quantitative assessment of individual health and the rate of aging of the human body on the basis of the system index of Biological age (BA); description of its essence and structure, requirements for tests - biomarkers of aging used as the index of BA, definition of possibilities and scope of application of the BA method in modern practice of Biomedicine. The use of modern methods of scientific analysis - a systematic approach to the analysis of the processes of human aging and determine its quantitative side - the value of BA, allows a reasonable approach to the choice of the number of BM, to take into account their information content and precision, and the cost of diagnostics and availability for different users, to take into account the specific objectives of the researcher. The use of the index-partial BA allows individual approaching the choice of biomarkers and create personalized panels for the definition of BA programs for the prevention of aging in personalized preventive medicine. The complexity of the content and calculation of indices of BA requires automation and the use of methods of modern computer science and computer calculations and programs. For this purpose, we have created special computer software for diagnosing aging by calculating the BA indices with the possibility of choosing BM and automatic calculation of indicators and conclusions.


2020 ◽  
Author(s):  
Myo Min Zaw ◽  
Manpreet Singh ◽  
Ronghui Ma ◽  
Liang Zhu

In this study, we first develop a whole body model based on measurements of a human body, with realistic boundary conditions incorporated before and after a person jumps into a hot tub. For the transient heat transfer simulation, the initial condition is the established steady state temperature field of the human body with appropriate clothing layer to ensure the thermal equilibrium of the body with its surroundings. Once the person is inside a hot tub, the Pennes bioheat equation is used to simulate the transient temperature elevations of the body, and the rising of the arterial blood temperature is solved by an energy balance equation modeling thermal exchange between body tissue and the blood in the body. The safe duration of soaking in hot tubs is then determined as affected by the hot tub water temperatures.


1987 ◽  
Vol 109 (3) ◽  
pp. 210-217 ◽  
Author(s):  
Farid M. L. Amirouche

A computer-automated approach for studying the human body vibration is presented. This includes vertical, horizontal, and torsional vibration. The procedure used is based on Finite Segment Modeling (FSM) of the human body, thus treating it as a mechanical structure. Kane’s equations as developed by Huston et al. are used to formulate the governing equations of motion. The connective tissues are modeled by springs and dampers. In addition, the paper presents the transient response of different parts of the body due to a sinusoidal forcing function as well as an impulse function applied to the lower torso in the vertical direction.


Author(s):  
Somayajulu D. Karamchetty

Engineers and scientists are able to understand and analyze the behavior of complex engineering systems in a wide range of critical technologies through hierarchical modeling followed by simulation of the model operation. This process results in a high fidelity integrated model as each level in the hierarchy is modeled in sufficient detail. The overall objective of this effort is to develop a sophisticated hierarchical model of the human body, followed by simulation of the model operation. In this initial research phase, the feasibility of the concept is explored and a framework for the model is described. A six-level model consisting of the whole body as a system, system of systems, organs, tissues, cells, and molecules is proposed and described. This paper explains that the human body is amenable to such hierarchical modeling and describes the benefits that can be achieved. The systems in the body deal with numerous processes: electrical, chemical, biochemical, energy conversion, transportation, pumping, sensing, communications, and so on. Control volume models for the organs in the body capture the mass and energy balance and chemical reactions. Tissue can be represented similar to structural components made of various biomaterials. Cells can be represented as a manufacturing and maintenance workforce assisted by molecular reactions. Following the representation of a healthy body, simulation runs by inserting faults and/or deficiencies in the operational parameters into the model could reveal the causes for specific diseases and illnesses. Such modeling and simulation will benefit medical, pharmaceutical, nutritional specialists, and engineers in designing, developing, and delivering products and services to enable humans to lead healthy lives.


2021 ◽  
Vol 27 (1) ◽  
pp. 4-11
Author(s):  
Nikolay Mikhailovich Vladimirov ◽  

Skeletal muscles are the largest organ in the human body, making up 40–50% of the total human body weight. This work is devoted to the study of physical activity on the athlete’s body. Given that the muscular system is more multifunctional than previously thought, and is able to aff ect many systems of the body through the synthesis and secretion of cytokines-classical regulators of the immune system, classifi ed as myokines. In this review article, we summarize our current knowledge of the main identifi ed and characterized myokines, focusing on their biological activity and functions. Through regular exercise, muscle-induced factors called myokines can exert and play an important role in protecting against many diseases.


Autism ◽  
2021 ◽  
pp. 136236132110443
Author(s):  
Hunter J Bennett ◽  
Taylor Jones ◽  
Kevin A Valenzuela ◽  
Justin A Haegele

Autistic persons exhibit variable movement, loading, and coordination patterns during walking. While much research has examined walking, little to no research exists regarding running for autistic persons despite its prevalence and benefits as a mode of physical activity. This study determined if autistic adolescents demonstrate increased coordination variability during running compared to matched controls. Seventeen autistic adolescents (aged = 13–18 years) and seventeen sex, age, and body mass index matched controls performed running at two matched speeds: self-selected of autistic adolescents and at 3.0 m/s. Modified vector coding was used to determine the patterns of movement for foot-shank, shank-thigh, left/right thigh, and contralateral arm-thigh coupling. Coordination variability, measuring cycle-to-cycle variability, was determined during loading response and pushoff phases. Mixed-model analyses of variance were used to determine group by speed interactions and main effects. Coordination variability was nearly 2× larger (all p < 0.001) in autistic adolescents compared to controls. Speed main effects were found for several sagittal plane couples during loading response. In agreement with walking analyses, this study illustrates that autistic adolescents run with increased intra-limb, inter-limb, and cross-body coordination variability. Like walking, increased coordination variability during running may negatively impact this mode of physical activity for autistic persons. Lay abstract Walking and running are popular forms of physical activity that involve the whole body (pelvis/legs and arms/torso) and are coordinated by the neuromuscular system, generally without much conscious effort. However, autistic persons tend not to engage in sufficient amounts of these activities to enjoy their health benefits. Recent reports indicate that autistic individuals tend to experience altered coordination patterns and increased variability during walking tasks when compared to non-autistic controls. Greater stride-to-stride coordination variability, when the task has not changed (i.e. walking at same speed and on same surface), is likely indicative of motor control issues and is more metabolically wasteful. To date, although, research examining running is unavailable in any form for this population. This study aimed to determine if coordination variability during running differs between autistic adolescents and age, sex, and body mass index matched non-autistic controls. This study found that increased variability exists throughout the many different areas of the body (foot-leg, left/right thighs, and opposite arm-opposite thigh) for autistic adolescents compared to controls. Along with previous research, these findings indicate autistic persons exhibit motor control issues across both forms of locomotion (walking and running) and at multiple speeds. These findings highlight issues with motor control that can be addressed by therapeutic/rehabilitative programming. Reducing coordination variability, inherently lessening metabolic inefficiency, may be an important step toward encouraging autistic youth to engage in sufficient physical activity (i.e. running) to enjoy physiological and psychological benefits.


Author(s):  
Swarup A. Zachariah ◽  
Anup K. Paul ◽  
Rupak K. Banerjee ◽  
Liang Zhu

Predicting thermal responses of the human body accurately during different exercise conditions is of increasing importance. Computing changes in the core body temperature (T c) during exercise require detailed modeling of both the body tissue temperature and the time-dependent blood temperature. Predicting changes in T c is challenging because the model needs to respond effectively to the changes in perfusion or sweating. Our study was to demonstrate the ability of a recently developed whole body heat transfer model. It simulates the tissue-blood interaction to predict the thermal response of the human body under different exercise intensities. The cases simulated were of a human being walking on a treadmill at 0.9, 1.2 and 1.8 m/s for 30 minutes. It was shown that T c was effectively regulated within 0.17 °C of the steady state value of 37.23 °C for the three cases by means of adjusting the cardiac output; varying between 15 to 25 liters per minute.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
A. Hernández-Reyes ◽  
F. Cámara-Martos ◽  
R. Molina-Luque ◽  
M. Romero-Saldaña ◽  
G. Molina-Recio ◽  
...  

Abstract Background There is evidence showing the effectiveness of a hypocaloric diet and the increase in physical activity on weight loss. However, the combined role of these factors, not only on weight loss but also body composition, remains unclear. The purpose of this study was to investigate the effect of a hypocaloric diet on the body composition of obese adult women throughout different degrees of physical activity during a weight loss program. Methods One hundred and seventeen healthy female volunteers were randomly assigned to one of the experimental groups: a control group with a low-level prescription of physical activity (1–4 METs), moderate physical activity group that performed 10.000 steps walking (5–8 METs) and intense physical activity group that trained exercises by at least 70% of VO2max three times a week (> 8 METs). All subjects followed a hypocaloric diet designed with a reduction of 500 kcal/day. Nutritional counseling was provided throughout the study period to help ensure dietary adherence. Results We found no differences in body weight compared to moderate and intense physical activity (ßstand. = − 0.138 vs. ßstand. = − 0.139). Body fat was lower in women following an intense activity (ßstand. = − 0.436) than those with moderate exercise (ßstand. = − 0.231). The high-intense activity also increased muscle mass at the end of the intervention, standing out above the moderate activity (ßstand. = 0.182 vs. ßstand. = 0.008). Conclusions These findings indicate that a hypocaloric diet, without prescription of physical activity, is adequate to lose weight in the short term (12 weeks), but physical activity is vital to modify the body composition in women with obesity. Body fat was lower when women practiced a moderate exercise compared to hypocaloric diet only, but an intense physical activity was the most effective protocol to obtain a reduction of body fat and maintain muscle mass. Trial registration The study protocol complied with the Declaration of Helsinki for medical studies, it was approved by the bioethical committee of Córdoba University, in the Department of Health at the Regional Government of Andalusia (Act n°284, ref.4156) and retrospectively registered in clinicaltrials.gov (NCT03833791). Registered 2 January 2019.


Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4471
Author(s):  
Marta Lorenzini ◽  
Wansoo Kim ◽  
Elena De Momi ◽  
Arash Ajoudani

In this work, we propose an online method to detect and approximately locate an external load induced on the body of a person interacting with the environment. The method is based on a torque equilibrium condition on the human sagittal plane, which takes into account a reduced-complexity model of the whole-body centre of pressure (CoP) along with the measured one, and the vertical component of the ground reaction forces (vGRFs). The latter is combined with a statistical analysis approach to improve the localisation accuracy, (which is subject to uncertainties) to the extent of the industrial applications we target. The proposed technique eliminates the assumption of known contact position of an external load on the human limbs, allowing a more flexible online body-state tracking. The accuracy of the proposed method is first evaluated via a simulation study in which various contact points on different body postures are considered. Next, experiments on human subjects with three different contact locations applied to the human body are presented, revealing the validity of the proposed methodology. Lastly, its benefit in the estimation of human dynamic states is demonstrated. These results add another layer to the online human ergonomics assessment framework developed in our laboratory, extending it to more realistic and varying interaction conditions.


Volume 2 ◽  
2004 ◽  
Author(s):  
Roya Narimani ◽  
Maryam Hoviattalab ◽  
Arash Abadpour ◽  
Azadeh Yadolahi

A large number of people are exposed to whole body vibration in their occupational life. Measuring vibration is an important tool in rehabilitation and biomechanical fields of research. We have proposed image processing as a new method to record and determine the frequency response of human body. The arranged set up for forced vibration consisted of an AC motor, a variable speed drive unit and a shaking table for producing one directional sinusoidal vibration. Volunteers were asked to stand on the shaking table at a relaxed posture. Two digital camcorders were used to capture the motion of colored pencil-dot markers on the skin of human body (forehead) and on the edge of the shaking table. After color spotting each frame, the binary image results were processed using new circle factor criteria proposed in this work, for fast finding circles based on second order statistics. The extracted points were calibrated using our own extended version of the direct linear transformation (DLT) method. Subsequently Vibration measuring software has been completely developed in Borland Delphi 5.0. Finally obtained displacement function of the body and the shaking table has been used in conjunction with Matlab 6.5 to prepare a proper algorithm for analyzing human body vibration. We discussed mechanical characteristics of the body by obtaining mechanical impedance and transmissibility from the shaking table to the head as example applications of the conducted software. The important point is the fact that all devices used in our developed measurement system are usually available in a biomechanics laboratory where a Gait system is functioning. This gives the opportunity for such laboratory to add vibration measurement to its capabilities without much excessive costs. The system has the advantage of lower noise sensitivity in comparison to accelerometer. The main advantage of this method is working with a simple user-familiar hardware with no external device attached to the subject and also a user-friendly-software.


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