Visco-Elastic Properties of Catheter Reinforced with Braids: Stress Relaxation under Two-Stage Step Strain for Different Deformation Paths

2012 ◽  
Vol 622-623 ◽  
pp. 1330-1334 ◽  
Author(s):  
Yasuyuki Kato ◽  
Show Krosawa ◽  
Masahito Ueda
Keyword(s):  
Stress Relaxation ◽  
Vascular Wall ◽  
Combined Loading ◽  
Two Stage ◽  
Relative Angle ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Step Strain ◽  
Surgical Operations

Generally, as for the material of catheter, a soft characteristic is necessary so as not to damage vascular wall etc. On the other hand, responsivity and enough rigidity are required for the surgical operations such as myocardial infarction or cerebral infarction. Therefore, the catheter, which is made of soft nylon resin and is reinforced with thin stainless wires so called “braid”, is chosen as the subject of this study. The purpose of this study is to reveal the effect of braid on the mechanical property of the catheter by investigating the relationship of the stress relaxation and the relative angle between the braid and the principal axis of stress. Especially, in order to investigate the stress relaxation under combined loading, the experiments of two-stage step strain for tension and torsion are carried out with different deformation paths. Consequentially, the phenomenon of the stress relaxation reduces with the relative angle becomes smaller. Moreover, the numerical model under two-stage step strain is proposed in this paper, and the validity of this model is confirmed by comparing the calculated results with the experimental results.

Stress Relaxation Behavior of Catheter Reinforced with Braid under Combined Loading for Bending and Torsion

2013 ◽  
Vol 372 ◽  
pp. 261-264 ◽  
Author(s):  
Yasuyuki Kato ◽  
Masahito Ueda
Keyword(s):  
Stress Relaxation ◽  
Principal Axis ◽  
Physical Property ◽  
Combined Loading ◽  
Two Stage ◽  
Relative Angle ◽  
Coefficient Of Viscosity ◽  
Relationship Of ◽  
The Relationship ◽  
Step Strain

The purpose of this research is to examine the physical property of the catheter, which made of soft nylon resin and is reinforced with thin stainless wires called braid. The effect of braid on the mechanical property of the catheter is revealed by investigating the relationship of the stress relaxation and the relative angle between the braid and the principal axis of stress under combined loading of bending and torsion. Inthe first place, in order to investigate the phenomenon of stress relaxation under combined loading, the experiments under single stage step strain have been carried out by changing the ratio of bending and torsion, and the relation between the coefficient of viscosity and the relative angle of the braid is revealed. In the second place, the experiment under two-stage step strain are conducted by changing the order of bending and torsion, and the effect of these loading histories on the visco-elastic properties is examined. Moreover, the numerical simulation under two-stage step strain is carried out by using the estimated coefficient of viscosity, and in this paper, the validity of this analytical model is confirmed by comparing with the experimental results.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Teaching oral requests

Pragmatics ◽  
2013 ◽  
Vol 23 (3) ◽  
pp. 499-517 ◽  
Author(s):  
Eleni Petraki ◽  
Sarah Bayes
Keyword(s):  
Conversation Analysis ◽  
English Language ◽  
Language Teaching ◽  
English Language Teaching ◽  
Cultural Appropriateness ◽  
Language Classroom ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Everyday Communication

Research in English language teaching has highlighted the importance of teaching communication skills in the language classroom. Against the backdrop of extensive research in everyday communication, the goal of this research was to explore whether current discourse analytic research is reflected in the lessons and communication examples of five English language teaching textbooks, by using spoken requests as the subject of investigation. The textbooks were evaluated on five criteria deriving from research on politeness, speech act theory and conversation analysis. These included whether and the extent to which the textbooks discussed the cultural appropriateness of requests, discussed the relationship of requests and other contextual factors, explained pre-sequences and re-requests and provided adequate practice activities. This study found that none of the coursebooks covered all of the criteria and that some coursebooks actually had very inadequate lessons. The results of the textbook analysis demonstrate that teachers using these five coursebooks and designers of future coursebooks must improve their lessons on requests by using pragmatics research and authentic examples as a guide.

Loffler's Endomyocardial Fibrosis, Eosinophilia, and Acute Lymphoblastic Leukemia

PEDIATRICS ◽  
1977 ◽  
Vol 59 (6) ◽  
pp. 950-951
Author(s):  
Fabio Pereira ◽  
Hernan Moreno ◽  
William Crist ◽  
Rufino Ermocilla
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lymphoblastic Leukemia ◽  
Normal Karyotype ◽  
Endomyocardial Fibrosis ◽  
Constant Feature ◽  
Cytogenetic Evidence ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Peripheral Blood Eosinophilia

Eosinophilia is a constant feature of Loffler's endomyocardial fibrosis.1,2 Three cases of this syndrome have been described in which acute lymphoblastic leukemia was concurrently present.3,4 Cytogenetic evidence in one of these cases suggested that the eosinophilia was "reactive" because the eosinophils had a normal karyotype while the lymphoblasts showed chromosomal aneuploidy.4 The subject of eosinophilia and eosinophilic syndromes has been extensively reviewed by others.5-8 The purpose of this report is to describe a boy with long-standing eosinophilia who presented with intractable heart failure, striking peripheral blood eosinophilia, and 38% lymphoblasts in the bone marrow. Current thoughts concerning the relationship of endomyocardial fibrosis, acute lymphoblastic leukemia, and eosinophilia are summarized.

Features of the Professional Direction of University Students in the Era of Digitalization

2021 ◽  
pp. 18-22
Author(s):  
A. Fatyhova ◽  
O. Bakanev ◽  
I. Kohanovskaya
Keyword(s):  
Higher Education ◽  
Negative Impact ◽  
Internal Conflict ◽  
Life Meaning ◽  
Digital Era ◽  
Personal Qualities ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
And Training

In the digital era, the success of the professional development of future specialists in the process of obtaining higher education largely depends on their professional orientation (PN). Despite the significant interest in the subject of the study, the problem of identifying the factors that affect PN remains poorly understood. The purpose of the study is to determine the factors of the formation of PN of students enrolled in training and retraining programs, and the features of PN in the digital era. The article reveals the content and structure of the PN of future specialists in the era of digitalization. According to the results of the empirical research, the relationship of students' PN with indicators of life-meaning orientations, motives for choosing a profession and training was revealed; the relationship between students' life-meaning orientations and indicators of motives for choosing a profession and training at the stage of digitalization of education. The factors influencing the personal condition, and the factors of the formation of the personal condition of students, who are trained according to the programs of training and retraining of specialists, have been determined. As a result of an empirical study, it was concluded that a negative impact on the formation of PN is created by factors caused by various life circumstances, lack of independence of decisions in choosing a profession, low reflection of life goals, prospects for the future, rigidity of volitional and personal qualities, internal conflict in the structure of personality relationships, low pleasure training and the like. At the same time, the level of PN is significantly higher among students who receive a second higher education and who understand its importance at the stage of digitalization of education.

EVALUATION OF THE VESSEL AGE BY APPLYING THE ACCELERATION PLETHYSMOGRAM ANALYSIS

2021 ◽  
pp. 61-67
Author(s):  
Елизавета Александровна Молчанова ◽  
Петр Вячеславович Лужнов
Keyword(s):  
Blood Vessels ◽  
Pulse Wave ◽  
Vascular System ◽  
Vascular Wall ◽  
Second Derivative ◽  
Contour Analysis ◽  
Physiological Factors ◽  
Vascular Age ◽  
Relationship Of ◽  
The Relationship

В работе приведены понятия жесткости, эластичности и тонуса сосудов, а также же их взаимосвязь с общим состоянием сосудистой стенки. Описан индекс, объединяющий влияние вышеперечисленных факторов на состояние сосудистой системы и дающий представление о возрасте сосудов пациента, а также показана связь этого индекса с возрастом человека. Представлен обзор способов определения возраста сосудов с помощью контурного анализа пульсовой волны. Среди предложенных способов был выделен подход на основе контурного анализа сигнала пульсовой волны, а также ее второй производной. В данном исследовании проводилась разработка алгоритма расчета показателя возраста сосудов (VA), базирующаяся на анализе сигнала и его второй производной. При этом особое внимание уделялось физической интерпретации параметров, входящих в состав расчетной формулы. С помощью представленного алгоритма в группе из трех испытуемых был определен сосудистый возраст. Из анализа полученных результатов было выявлено влияние физиологических факторов на значение возраста сосудов. Предложены методики, позволяющие исключить влияние этих факторов на значения показателя VA и тем самым получить более точные результаты. Также представлены стратегии дальнейшего развития исследований в этом направлении In The paper presents the concepts of rigidity, elasticity and tone of blood vessels, as well as their relationship with the general state of the vascular wall. An index is described that combines the influence of the above factors on the state of the vascular system and gives an idea of the age of the patient's vessels, and also shows the relationship of this index with the age of a person. An overview of the methods for determining the age of blood vessels using the contour analysis of the pulse wave is presented. Among the proposed methods, an approach based on the contour analysis of the pulse wave signal, as well as its second derivative, was singled out. In this study, an algorithm was developed for calculating the indicator of vascular age (VA), based on the analysis of the signal and its second derivative. In this case, special attention was paid to the physical interpretation of the parameters included in the calculation formula. Using the presented algorithm, vascular age was determined in a group of three subjects. From the analysis of the results obtained, the influence of physiological factors on the value of the age of the vessels was revealed. Methods are proposed that allow to exclude the influence of these factors on the values of the VA indicator and thereby obtain more accurate results. Also presented are strategies for the further development of research in this direction

scholarly journals Unusual Deviation of the Main Foramen from the Root Apex

2016 ◽  
Vol 27 (5) ◽  
pp. 589-591 ◽  
Author(s):  
Marco Aurélio Versiani ◽  
Hany Mohamed Aly Ahmed ◽  
Manoel Damião de Sousa-Neto ◽  
Gustavo De-Deus ◽  
Paul Michael Howell Dummer
Keyword(s):  
Computed Tomography ◽  
Short Communication ◽  
Root Apex ◽  
Micro Computed Tomography ◽  
Tooth Type ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Substantial Distance

Abstract The relationship of the main foramen to the anatomic root apex has been the subject of several studies. Although they are anatomically close, they rarely coincide, and their distance can vary according to age or tooth type, ranging from 0.2 to 3.0 mm. The aim of this short communication was to evaluate the distance between the main foramen of independent middle mesial canals (MMCs) and the anatomical mesial root apex of mandibular first molars using the micro-computed tomography. Twenty-five mandibular first molars with MMCs were scanned (resolution of 9.9 µm), and the distance from its main foramen to the anatomical apex was evaluated. Overall, the distance ranged from 0.2 to 2.4 mm; however, in 3 specimens the distance was greater than 3 mm. This report demonstrates that the exit of the main foramen of the MMC varies considerably and could approach a substantial distance from the anatomical apex greater than previously reported in the literature.

scholarly journals Objective psychology. Academician V. Bekhterev. Issue I. St. Petersburg. 1907 year

1907 ◽  
Vol XIV (3-4) ◽  
pp. 194-196
Author(s):  
V. Osipova
Keyword(s):  
Mental Life ◽  
Subjective Experiences ◽  
The Subject ◽  
And Control ◽  
Relationship Of ◽  
The Relationship ◽  
Living Creature

The author begins his work with the words that the psychology that he will expound bears little resemblance to the psychology that has been the subject of study until now. In objective psychology, there should be no place for questions about subjective processes or processes of consciousness, therefore there should be no place for introspection. Self-observation is not enough even to study one's own mental life. Objective psychology has in mind to study and explain only the relationship of a living creature to the surrounding conditions that affect it in one way or another, without aiming to find out those internal or subjective experiences, which are known as conscious phenomena and which are accessible only to self-observation. All mental items should only be subject to objective registration and control.

scholarly journals The specifics of interpretation of the history in the story by A. Doronin «A Wolf Ravine»

2021 ◽  
Vol 11 (1) ◽  
pp. 139-147
Author(s):  
S. V. Sheyanova ◽  
◽  
N. M. Yusupova ◽  
Keyword(s):  
Literary Criticism ◽  
Historical Narrative ◽  
Volga Region ◽  
Psychological States ◽  
The Real ◽  
The Subject ◽  
The Individual ◽  
Relationship Of ◽  
First Time ◽  
The Relationship

Introduction: at present the reader’s audience is particularly interested in creative experiments in which the historical fate of the Russian peasantry in the «turning» eras is artistically comprehended. The article is devoted to the study of the problem-thematic range of modern Mordovian historical prose. The subject of analysis is the peculiarity of the reception of the period of collectivization and dekulakization in the story by Erzyan prose writer A. Doronin «A Wolf Ravine». Objective: to reveal the features of the artistic reconstruction of the events of the 1930s, the modeling of the relationship between a man and society in the story by A. Doronin «A Wolf Ravine».Research materials: the story by A. Doronin «A Wolf Ravine». Results and novelty of the research: the historical story « A Wolf Ravine » for the first time becomes the object of scientific understanding and is introduced into the context of Finno-Ugric literary criticism. A. Doronin artistically interprets the real events and circumstances of the resettlement of dispossessed peasants of the Volga region to the uninhabited steppes of Kazakhstan. As a result of the study, we conclude that the actualization of this problem-thematic cluster is due to the creative concept of the historical writer; the individual author’s approach to the reconstruction of historical narrative can be traced in the writer’s desire to realistically reveal the relationship of personality and society in the tragic 1930s; to analyze intentions of people and of the psychological states of the characters. Problems of a sociopolitical nature, actualized in the story, are filled with philosophical, axiological content, and lead to a multi-faceted understanding of the «man and history» problem.

scholarly journals Spinoza’s affective aesthetics: Art and architecture from the viewpoint of life

2021 ◽  
pp. 64-72
Author(s):  
Gökhan Kodalak
Keyword(s):  
Subject Matter ◽  
Aesthetic Theory ◽  
The Subject ◽  
Relationship Of ◽  
Art And Architecture ◽  
The Relationship

There is a peculiar aesthetic undercurrent traversing Baruch Spinoza’s philosophy, harbouring untapped potentials and far-reaching consequences for contemporary discussions on aesthetics. The relationship between aesthetics and Spinoza’s philosophy, however, has been nothing but a huge missed encounter, resulting in the publication of only a few books and a handful of articles throughout a vast period of more than three-and-a-half centuries. Which begs the question: might there be, despite our persistent negligence, much more to the relationship of Spinoza and aesthetics than first meets the eye? I will argue that there might be. For once Spinoza’s philosophy as a whole, ranging from his philosophical and political treatises to his private letters and unfinished manuscripts, is read between the lines, latent seeds of a peculiar aesthetic theory become visible—an aesthetic theory that moves beyond subjective and objective approaches that have come to dominate the field, and rather grounds itself on affective interactions and morphogenetic processes. A subterranean journey through Spinoza’s affective aesthetics constitutes the subject matter of this paper, which interweaves subtle aesthetic hints buried deep within his philosophical archive, while unfolding relevant ramifications of these promising discoveries for the current aesthetic discourse.

Sign in / Sign up

Export Citation Format

Share Document