Mobility Determination of Mechanisms Based on Rigidity Theory

2012 ◽  
Author(s):  
Michael Slavutin ◽  
Offer Shai ◽  
Andreas Müller
Keyword(s):  
The Body ◽  
Rigidity Theory ◽  
Rigidity Matrix ◽  
Planar Mechanisms ◽  
Prismatic Joints ◽  
Unified View ◽  
Joint Rigidity ◽  
Pebble Game ◽  
First Time

Rigidity theory deals mostly with the topological computation in mechanical systems, i.e. it aims at making generic statements. Mechanism theory is mainly concerned with the geometrical analysis but again also with generic statements. Even more so for mobility analysis where one is interested in both the generic mobility and that of a particular mechanism. In rigidity theory the mathematical foundation is the topology representation using bar-joint and body-bar graphs, and the corresponding rigidity matrix. In this paper novel geometric rules for constructing the body-bar rigidity matrix are derived for general planar mechanisms comprising revolute and prismatic joints. This allows, for the first time, the treatment of general planar mechanisms with the body-bar approach. The rigidity matrix is also derived for spatial mechanisms with spherical joints. The bar-joint rigidity matrix is shown to be a special case of body-bar representation. It is shown that the rigidity matrices allow for mobility calculation as shown in the paper. This paper is aimed at supplying a unified view and as a result to enable the mechanisms community to employ the theorems and methods used in rigidity theory. An algorithm for mobility determination — the pebble game — is discussed. This algorithm always finds the correct generic mobility if the mechanism can be represented by a body-bar graph.

Mass Flow and Derivative Moment of Inertia Flow in Planar (Geared) Linkages

1992 ◽  
Author(s):  
Zhonghe Ye ◽  
M. R. Smith
Keyword(s):  
Mass Flow ◽  
Kinematic Analysis ◽  
Moment Of Inertia ◽  
Force Balance ◽  
New Concepts ◽  
Prismatic Joints ◽  
Planar Linkages ◽  
First Time ◽  
Shaking Moment

Abstract The paper describes a method for the determination of the conditions for the complete shaking force and shaking moment balancing of planar linkages, including geared linkages, with revolute and prismatic joints. The conditions may be written down without the need for any kinematic analysis of the linkage by the application of two new concepts. These are the concept of mass flow for complete shaking force balance and the concept of derivative moment of inertia flow for complete shaking moment balance, the second of which is described here for the first time. A number of examples demonstrate the power of the method.

Chelyabinsk Meteorite

2021 ◽  
Author(s):  
Olga Popova
Keyword(s):  
Energy Deposition ◽  
Seismic Waves ◽  
The Body ◽  
Structure And Properties ◽  
Ural Mountains ◽  
Asteroid Impact ◽  
Unusual Event ◽  
The Earth ◽  
First Time

The asteroid impact near the Russian city of Chelyabinsk on February 15, 2013, was the largest airburst on Earth since the 1908 Tunguska event, causing a natural disaster in an area with a population exceeding 1 million. On clear morning at 9:20 a.m. local time, an asteroid about 19 m in size entered the Earth atmosphere near southern Ural Mountains (Russia) and, with its bright illumination, attracted the attention of hundreds of thousands of people. Dust trail in the atmosphere after the bolide was tens of kilometers long and was visible for several hours. Thousands of different size meteorites were found in the areas south-southwest of Chelyabinsk. A powerful airburst, which was formed due to meteoroid energy deposition, shattered thousands of windows and doors in Chelyabinsk and wide surroundings, with flying glass injuring many residents. The entrance and destruction of the 500-kt Chelyabinsk asteroid produced a number of observable effects, including light and thermal radiation; acoustic, infrasound, blast, and seismic waves; and release of interplanetary substance. This unexpected and unusual event is the most well-documented bolide airburst, and it attracted worldwide attention. The airburst was observed globally by multiple instruments. Analyses of the observational data allowed determination of the size of the body that caused the superbolide, its velocity, its trajectory, its behavior in the atmosphere, the strength of the blast wave, and other characteristics. The entry of the 19-m-diameter Chelyabinsk asteroid provides a unique opportunity to calibrate the different approaches used to model meteoroid entry and to calculate the damaging effects. The recovered meteorite material was characterized as brecciated LL5 ordinary chondrite, in which three different lithologies can be distinguished (light-colored, dark-colored, and impact-melt). The structure and properties of meteorites demonstrate that before encountering Earth, the Chelyabinsk asteroid had experienced a very complex history involving at least a few impacts with other bodies and thermal metamorphism. The Chelyabinsk airburst of February 15, 2013, was exceptional because of the large kinetic energy of the impacting body and the damaging airburst that was generated. Before the event, decameter-sized objects were considered to be safe. With the Chelyabinsk event, it is possible, for the first time, to link the damage from an impact event to a well-determined impact energy in order to assess the future hazards of asteroids to lives and property.

scholarly journals Investigation of the irritant effects and allergenic properties of the Iron(IV) clathrochelate complexes

2020 ◽  
Vol 22 (97) ◽  
pp. 130-135
Author(s):  
V. B. Dukhnitsky ◽  
I. M. Derkach ◽  
S. S. Derkach ◽  
I. O. Fritsky ◽  
M. O. Plutenko ◽  
...  
Keyword(s):  
Body Weight ◽  
The Body ◽  
New Drugs ◽  
Laboratory Animals ◽  
Routes Of Administration ◽  
Skin Fold Thickness ◽  
Skin Fold ◽  
First Time ◽  
Clathrochelate Complexes

During the preclinical studies of new drugs, the study of the degree of manifestation of their irritant and allergenic effects affects subsequent clinical studies, for example the routes of administration, the need to add excipients to reduce irritation. The article presents the results of studies of the irritant effects and allergenic properties of the Iron in rare unconventional valence – IV. The irritant effect of the Iron(IV) clathrochelate complexes on the skin was studied comprehensively. 20 rabbits were divided into 4 groups (control and three experimental), 5 animals each. The  ointment on the vaseline and aqueous solution of the Iron(IV) clathrochelate complexes was applied to the skin of rabbits of the experimental groups. Also this solution was introduced subcutaneously. The investigated dosage forms were used at a dose of 1 ml/kg body weight (based on the active ingredient 500 mg/kg body weight of the laboratory animal). The results of the studies showed that of the Iron(IV) clathrochelate complexes has no irritant properties when used externally and is characterized by a lack of local reaction by subcutaneous injection. Determination of allergenic properties was performed by detecting itching and swelling in the guinea pigs in animals which were sensitized with this substance. In addition, in order to assess the severity of the inflammatory reaction, the skin temperature was determined before the experiment and on the 20th day of the experiment, and the skin fold thickness was measured using a caliper. The results of the studies showed that there is no allergic action of the Iron(IV) clathrochelate complexes. The results of the ophthalmic test on laboratory animals confirmed the data obtained.Therefore, comprehensive studies of the irritant and allergenic effects of the Iron(IV) clathrochelate complexes were performed for the first time. The Iron(IV) clathrochelate complexes in the form of ointment and solution does not irritate the skin and mucous membranes and has no allergenic properties to the body of the laboratory animals.

scholarly journals Novyi Mishor – first country-style resort on the South Coast of Crimea (1898-1920): reconstruction of sociocultural history

2020 ◽  
pp. 103-127
Author(s):  
Andrey Vasil'evich Karagodin ◽  
Mariya Mikhailovna Petrova
Keyword(s):  
The Body ◽  
South Coast ◽  
Russian Society ◽  
The South ◽  
Historical Sources ◽  
Starting Point ◽  
History Of ◽  
The Subject ◽  
First Time

The subject of this research is the history of the first of country-style resort appeared on the South Coast of Crimea at the turn of the XIX – XX centuries on the lands of country estates of New Mishor belonged to Shuvalov-Dolgorukov family. The phenomenon of country-style construction on the South Coast of Crimes, which starting point was the foundation of the Novyi Mishor, is viewed in the context of the processes of economic and sociocultural modernization of Russian society, formation of self-identification mechanisms of the emerging “middle class”, and new urban culture. Special attention is given to the period from 1917 to 1920, when the cultural figures left the capital and resided in the villages of Novyi Mishor. Based on examination the body of historical sources, many of which introduced to the scientific discourse for the first time, the author formed the database of villages and countryside residents of Novyi Mishor. A vast array of archival funds, reference literature, sources of personal provenance (memoirs, correspondence), and visual sources was attracted in the course of research. The novelty of consists in establishment of identities and social status of the residents of country resort of Novyi Mishor, determination of a range of sources for its further research, reconstruction of chronology of the development of this resort, details of everyday life and mentality traits of the residents, among which were the prominent figures of culture and art of Russia of that time – writers, actors, painters, scholars, and philanthropists.

scholarly journals Noteridae, Dytiscidae (Coleoptera) du Gabon (8ème partie). Monts de Cristal

2011 ◽  
Vol 152 (2) ◽  
pp. 177 ◽  
Author(s):  
Armando Bilardo ◽  
Saverio Rocchi
Keyword(s):  
New Species ◽  
Related Species ◽  
National Park ◽  
The Body ◽  
Ecological Data ◽  
New Subspecies ◽  
Two New Species ◽  
First Time ◽  
A New Species

Noteridae, Dytiscidae (Coleoptera) from Gabon (eighth part). Monts de Cristal. This work concerns the Coleoptera Hydradephaga collected in eight localities of Monts de Cristal (Republic of Gabon) included locality of Tchimbélé into the National Park of Monts de Cristal in years 2006 - 2010; altogether 76 species are listed (3 Noteridae and 73 Dytiscidae) of which 51 species found in the Park. The authors describe two new species: <em>Copelatus angouei</em> (group <em>consors</em>, sensu Guignot, 1961, distinguishable from other species of group by small size, the robust conformation, the upper side clearly microreticulate covered by fine and thick punctuation which give it an opaque look and by characteristic penis), <em>Copelatus nguemai</em> (group <em>irinus</em>, subgroup <em>assimilis</em>, sensu Guignot, 1961, related to assimilis Régimbart, 1895, distinguishable by longer spine of metatibia clearly curved at third apical in both sexes and by characteristic penis) and one new subspecies: <em>Copelatus lasckonyi tchimbelensis</em> (group <em>irinus</em>, subgroup <em>irinus</em>, sensu Guignot, 1961, characterized by very small size, by narrowed profile of the body from shoulders in some specimens and by the upper side finely microreticulate, penis, very characteristic, is identical to typical form). The examination of two sintypes of <em>Copelatus variegatus</em> Régimbart, 1895 (group <em>erichsoni</em>, subgroup <em>atrosulcatus</em>, sensu Guignot, 1961) of Muséum Nationale d’Histoire Naturelle of Paris and of specimens of related species of the Museums of Tervuren and Bruxelles permitted the determination of the specimens of <em>C. variegatus c</em>ollected during research and the redescription of the species known till now by the two sintypes (here respectively designate lectotype and paralectotype); meanwhile a new species has been identified: <em>Copelatus mendax</em>, belonging to same group and subgroup of <em>C.</em> <em>variegatus</em>, misidentified with veritable <em>C. variegatus</em>. Some <em>taxa</em> of aquatic macroinvertebrates (Hexapoda, Malacostraca, <em>Clitellata</em> et Mollusca) in the zone collected and determined by a Researcher of IRAF (CENAREST, Gabon), Blaise Mboye Rollinat, who had participated in mission 2010, are furnished. Observations on some of the collected species and some ecological data of the biocenoses that populate the zone and some considerations on aquatic Coleoptera habitats are presented. The name of the species <em>Copelatus efoutensis</em> Bilardo &amp; Rocchi, 1995 is amended in efotensis<em>.</em> <em>Hydrovatus senegalensis</em> Régimbart, 1895 and <em>Uvarus barombicus</em> Bilardo, 1982 are signalled for the first time of Gabon.

scholarly journals Purinergic regulation: From a risky hypothesis to a triumphant theory

2021 ◽  
Vol 16 (3) ◽  
pp. 190-202
Author(s):  
Mohammad Kamran Sarkandi ◽  
◽  
Natalia Serebryanaya ◽  
◽  
Keyword(s):  
Functional State ◽  
Purinergic Receptors ◽  
Purinergic Signaling ◽  
Signal Transmission ◽  
The Body ◽  
Extracellular Nucleotides ◽  
Receptor Interaction ◽  
First Time

With the discovery of the ATP structure in 1929, significant progress was made in understanding the role of nucleosides and nucleotides in the body. One of the most important breakthroughs is associated with the determination of the function of an autacoid in ATP, a participant in purinergic signal transmission. For the first time, this function of ATP was pointed out by Professor Geoffrey Burnstock in 1972. Purinergic signaling activators are extracellular nucleotides including ATP, ADP, UTP, UDP, and adenosine nucleoside. The purinergic signaling pathway begins with the synthesis and intracellular accumulation of nucleotides, and then their release from the cell under various physiological and pathological conditions. In the extracellular spaces, nucleotides are hydrolyzed by various enzymes with the removal of phosphate groups, which leads to the appearance of various regulatory molecules that interact with P1 and P2 purinergic receptors. This ligand-receptor interaction changes the functional state of the target cell. In turn, the expression of purinergic receptors changes depending on the functional state of the cell. The participation of purinergic regulation in the development of many diseases indicates that by changing the concentration of signaling molecules, it is possible to change the course of pathological processes, in particular the activity of inflammation and the direction of immune responses. This article provides a brief review of the literature on the structure of nucleotide and nucleoside autacoids, enzymes involved in their metabolism, specific purinergic receptors.

Gender determination of caucasoid hair using image analysis

1993 ◽  
Vol 51 ◽  
pp. 216-217
Author(s):  
T.B. Ball ◽  
W.M. Hess
Keyword(s):  
Image Analysis ◽  
Cross Sections ◽  
Scalp Hair ◽  
The Body ◽  
Equivalent Diameter ◽  
Cross Sectional ◽  
Hair Samples ◽  
Length Width ◽  
Morphological Differences

It has been demonstrated that cross sections of bundles of hair can be effectively studied using image analysis. These studies can help to elucidate morphological differences of hair from one region of the body to another. The purpose of the present investigation was to use image analysis to determine whether morphological differences could be demonstrated between male and female human Caucasian terminal scalp hair.Hair samples were taken from the back of the head from 18 caucasoid males and 13 caucasoid females (Figs. 1-2). Bundles of 50 hairs were processed for cross-sectional examination and then analyzed using Prism Image Analysis software on a Macintosh llci computer. Twenty morphological parameters of size and shape were evaluated for each hair cross-section. The size parameters evaluated were area, convex area, perimeter, convex perimeter, length, breadth, fiber length, width, equivalent diameter, and inscribed radius. The shape parameters considered were formfactor, roundness, convexity, solidity, compactness, aspect ratio, elongation, curl, and fractal dimension.

Disability as a social phenomenon

2020 ◽  
pp. 22-38
Author(s):  
Natalia Guseva ◽  
Vitaliy Berdutin
Keyword(s):  
Social Protection ◽  
Russian Society ◽  
Stage Model ◽  
High Quality ◽  
Rehabilitation Programs ◽  
Current State ◽  
The Social ◽  
Consistent Solution ◽  
First Time

At present, the problem of establishing disability is a point at issue in Russia. Despite the fact that medical criteria for disability are being developed very actively, high-quality methods for assessing social hallmarks are still lacking. Since disability is a phenomenon inherent in any society, each state forms a social and economic policy for people with disabilities in accordance with its level of development, priorities and opportunities. We have proposed a three-stage model, which includes a system for the consistent solution of the main tasks aimed at studying the causes and consequences of the problems encountered today in the social protection of citizens with health problems. The article shows why the existing approaches to the determination of disability and rehabilitation programs do not correspond to the current state of Russian society and why a decrease in the rate of persons recognized as disabled for the first time does not indicate an improvement in the health of the population. The authors proposed a number of measures with a view to correcting the situation according to the results of the study.

Determination of Lead Content in Red Colored Lipsticks from Mandalay Market by Flame Atomic Absorption Spectrophotometer

2018 ◽  
Vol 30 (3) ◽  
pp. 167-173
Keyword(s):  
Sampling Procedure ◽  
The Body ◽  
Lead Content ◽  
Social Psychological ◽  
Allowable Limit ◽  
Flame Atomic Absorption ◽  
Therapeutic Benefits ◽  
Flame Atomic Absorption Spectrophotometer ◽  
Exposure Levels

Red colored lipstick is the most widely used cosmetic product. Although lipstick gives a lot of social, psychological and therapeutic benefits, it may harm the consumers. Because some lipsticks contain a considerable amount of heavy metal especially lead. Lead is being used in lipstick mainly for the pigments required to obtain needed colors. Lead accumulates in the body over time and lead-containing lipstick applied several times a day, every day, combined with lead in water and other sources, could add up to significant exposure levels. Therefore, this study was aimed to determine lead content in red colored lipsticks from market. This study was laboratorybased, analytical study by using 25 lipstick samples. Red colored lipsticks were bought from Mandalay Market by random sampling procedure and they were completely coded to avoid the bias. Then, lead content in coded samples was determined by Flame AAS according to International Conference on Harmonization (ICH) guideline. Lead contents of 88% of the lipsticks samples were more than specified limit (20 ppm) of Food and Drug Administration, United States. All of them, lead content was highest in counterfeit lipsticks group. Among the tested lipstick samples, lipstick with lowest lead content was LE-RL 01 (15.74 ppm) and the lipstick with highest lead content was CF-RL 01(60.09 ppm). In conclusion, lead contents of red colored lipsticks (22 out of 25) from market samples were higher than allowable limit (20 ppm).

Fast Method for the Determination of Residual Solvents in Radiopharmaceutical Products

2017 ◽  
Vol 68 (4) ◽  
pp. 666-670 ◽  
Author(s):  
Mirela Mihon ◽  
Catalin Stelian Tuta ◽  
Alina Catrinel Ion ◽  
Dana Niculae ◽  
Vasile Lavric
Keyword(s):  
Gas Chromatography ◽  
Control Method ◽  
Limit Of Detection ◽  
The Body ◽  
Biologically Active ◽  
Injection Technique ◽  
Fast Method ◽  
Residual Solvent ◽  
Residual Solvents

The aim of this work was the development and validation of a fast analytical method to determine the residual solvents content in radiopharmaceuticals such as: 18F-Fluorodeoxyglucose (18F-FDG), 18F-Fluoroestradiol (18F-FES), 18F-Fluorothymidine (18F-FLT),18F-Fluoromisonidazole (18F-FMISO). Radiopharmaceuticals are radioactive preparations for medical purposes used in nuclear medicine as tracers in diagnostic imaging and treatment of certain diseases. Positron Emission Tomography (PET) is a medical imaging technique that consists in introducing into the body of a small amount of a biologically active chemical compound labelled with a short lived positron-emitting radioisotope (18F, 11C, 68Ga). Residual solvents are critical impurities in radiopharmaceuticals that can affect labelling, stability and physicochemical properties of drugs. Therefore, the determination of these solvents is essential for quality control of radiopharmaceuticals. Validation of the control method for residual solvents by gas chromatography is referred by the European Pharmacopoeia using a special injection technique (head space). The parameters of the method, which comply with International Conference on Harmonization guidelines, are: accuracy, precision, linearity, limit of detection, limit of quantification and robustness. The proposed method (direct gas chromatography injection) proved to be linear, precise, accurate and robust. Good linearity was achieved for all the solvents and correlation coefficients (R2) for each residual solvent were found more than 0.99.

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