A localized stenosis or aneurysm is a discontinuity that presents the pulse wave produced by the contracting heart with a reflection site. However, neither wave speed ( c) in these discontinuities nor the size of reflection in relation to the size of the discontinuity has been adequately studied before. Therefore, the aim of this work is to study the propagation of waves traversing flexible tubes in the presence of aneurysm and stenosis in vitro. We manufactured different sized four stenosis and four aneurysm silicone sections, connected one at a time to a flexible ‘mother’ tube, at the inlet of which a single semi-sinusoidal wave was generated. Pressure and velocity were measured simultaneously 25 cm downstream the inlet of the respective mother tube. The wave speed was measured using the PU-loop method in the mother tube and within each discontinuity using the foot-to-foot technique. The stenosis and aneurysm dimensions and c were used to determine the reflection coefficient ( R) at each discontinuity. Wave intensity analysis was used to determine the size of the reflected wave. The reflection coefficient increased with the increase and decrease in the size of the aneurysm and stenosis, respectively. c increased and decreased within stenosis and aneurysms, respectively, compared to that of the mother tube. Stenosis and aneurysm induced backward compression and expansion waves, respectively; the size of which was related to the size of the reflection coefficient at each discontinuity, increases with smaller stenosis and larger aneurysms. Wave speed is inversely proportional to the size of the discontinuity, exponentially increases with smaller stenosis and aneurysms and always higher in the stenosis. The size of the compression and expansion reflected wave depends on the size of R, increases with larger aneurysms and smaller stenosis.
The Sound of the letter (ق) in the Contemporary Arabic Dialects
Since his first existence on earth, human had formed a connecting link for a regressive, kinetic and developed relationship that comes from a semi-complicated interaction between natural environment and constructed environment, and this resulted in the survival of human and his existence continuance. Constructed environment enabled human to survive the natural environment inconstancies and enemies as predators, also it helped him to feel safe, comfortable and to practice his everyday life activities...etc. This alternative interaction resulted in creating a civilized legacy for a group of landmarks that tell about the development of this relationship by elemental output that reached us either by documents and manuscripts or as an existed
... Show MoreThanks and gratefulness be to Allah , the most merciful , and prayers be on his messenger and our prophet mohammed and his descendants.The voices have great influence on the diversity of methods of complaints and implication in the Qur'anic expression through
their inspiration , forms and notes. They also have influence on performing semantic and psychological condition of the emitter . that is because of the connection between the complaints and human behavior and emotions , since it is considered as the outlet by which the human expresses his repressed desired and instincts . he resorted to it " when he is helpless physically and mentally i.e. he cannot reach his goals or satisfy his needs." Complaints come from deprivation , social
دور اللوبي الصهيوني في صنع السياسة الأمريكية
The Semitic Languages have her its Articulatory That what we attend to discuss In this Research to Represent the Relation Between them and the Light Of Semitics a Comparative Studies where ever It's Exists The Semitic languages by comparing the words whish most Semitic languages share with each other. We call such Words the Semitic denominator. We have adopted a comparative framework in our Research, which is based on comparing an Arabic word with its Semitic counterpart in Order to identify the forms that control grammatical change in both language
... Show MoreThe study of images in the cognitive field receives considerable attention by researchers, whether in the field of media and public relations or in other humanities. Due to the great importance in shaping trends of public opinion, especially trends that individuals and the behaviors of people, institutions or ideas are determined by forming images that they hold in their minds towards these persons or institutions. Modern enterprises have realized, whether they are governmental ministries and official departments or non-governmental organizations as civil society organizations, the importance of studying the dominant image in the minds of the masses and make decisions and draw plans to configure this image as these institutions wishes.&n
... Show MoreThe theater benefited from the concept of (hypertext) to create different virtual worlds. The four chapters of the research included the first (methodological framework), the second (theoretical framework) came in two sections (hypertext, its concepts and applications) and (hypertextual space in theatrical performance), and the investigations resulted in indicators, including:
1- Hypertext is interacting interactively, but it is organized by correlation as a basic feature that defines it with different manifestations.
2- The hypertext combines the word with other formative elements that reduce a set of tagged information (word, image, light, shadow, color, number).
In the third chapter (research procedures) (Lord play) was
The aim of organizational contemporary is development man power active, in spit-of there are littlie resources. But in the Iraqi environment there are too much resources with performance inhabiting. specially in the ministry of water resources (sample of this research), about dryness and lower levels of rivers. There for this study have some important variable, it is ethical leadership & transformational leadership as (independent variable), and Perceived organizational support(dependent variable). Over here to invest with authority on the problem of research, is weakness harmony between employed perception and the pattern of leadership. We find decline in of reaction of organ compound between the variable to weaken high perf
... Show MoreHuman cerebral cortex is the outer folded neuronal layer and represents major part of the cerebrum with enormous functions. It is a laminar structure, easily visualized grossly. Previous studies showed that the Superior Temporal gyrus is one of the thickest cerebral cortex regions, reaching (about 4 mm). The Electron microscope study was made on 6 samples taken to measure the neuronal soma dimension of the large pyramidal cells present in the internal pyramidal cortical layer V in different age groups and gender. Aging process was obvious on the large pyramidal cells of the cerebral cortex, in which their neuronal soma dimensions showed shrinkage with age progression. But statistically there was no differences in the values between males an
... Show MoreAbstract In light of the changing conditions that prevail in society, and the intense competition that institutions and countries are forced to face, especially after the opening of markets, and the transformation of the world into what is called a small village, entrepreneurship has emerged as an important tool for dealing with the developments of societies, whether it is related to individual business projects or Economics for national business, leadership was the key to any driving force towards achieving growth. Today, women are no longer captive to a specific orientation, but rather all horizons and fields of work have been opened to them, and they have been able to occupy the most important economic, voluntary, service, and
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