Principles Of Ultrasound Technology In Medical Imaging Of Non Ionization Images

The X-ray tube is one of the most important components in any X-ray system. In the beginning, physicists and physicians used gas ion tubes. The so-called Coolidge tube applied a high vacuum and is still used today. Medical examinations have required continuously improved designs of X-ray tubes (smaller focal spots at a higher output). The principle of the Goetze line focus is still applied in any diagnostic X-ray tube. Different anode materials and the rotating anode contributed to an increased output and reduced exposure time. Bearings needed special attention. Spiral groove bearings are the most advanced design today. The heat storage capacity of the anode and the tube housing assembly influences examination time and patient throughput. Cardiac imaging required less motion blurring in cine film images and increasing radiation exposure in interventional procedures called for measures to reduce dose. Protection against radiation and electric shock has always been a concern of design engineers. Focal spot sizes dedicated to specific applications and heat management within the total tube housing assembly will be future issues. Even with the event of ultrasound and MR technology, X-ray procedures will still be applied for diagnostic and interventional purposes.

SUBVERTING JOSEPH CAMPBELL'S HEROIC IDEOLOGY:LUCIFER EFFECT – THE GOOD / EVIL DIVIDE IN THE PORTRAYAL OF RAVANA IN RAMAYANA

For centuries Ramayana has been the centre of contention for the critics with respect to dei?cation of Rama, epitome of virtue and defamation of Ravana, the king of the darkest kind. Joseph Campbell's de?nition of a Hero resides with a person's heroic quest to achieve something that is beyond himself through his encounter with a challenging enemy and his victorious return. Ravana, the antagonist, underwent a challenging quest and was unconquerable until he was faced with his one tragic ?aw – his lust for Sita. Upon looking through the lens of deconstruction, this abduction doesn't make Ravana the antagonist of the plot but actually a Tragic Hero of Aristotle. This Hamartia of Ravana was not implied by him but was imposed upon him by the circumstances which make him a fallen hero – the Lucifer of Genesis. This paper aims to apply Philip Zimbardo's Lucifer Effect theory to explore Campbell's ideology of heroism with reference to Ravana and also attempts to answer the question whether Ravana is the greatest villain or is he actually a situational victim, who is outshined as a villain by his tragic ?aw intensi?ed by circumstantial pressures

Principles & Functions Of Conventional & Digital X-Rays Imaging Systems In Diagnosis

Digital radiography (DR) is an advanced form of x-ray inspection which produces a digital radiographic image instantly on a computer. This technique uses x-ray sensitive plates to capture data during object examination, which is immediately transferred to a computer without the use of an intermediate cassette. The incident x-ray radiation is converted into an equivalent electric charge and then to a digital image through a detector sensor. Compared to other imaging devices, flat panel detectors, also known as digital detector arrays (DDAs) provide high quality digital images. They can have better signal-to-noise ratio and improved dynamic range, which, in turn, provides high sensitivity for radiographic applications. Flat panel detectors work on two different approaches, namely, indirect conversion and direct conversion. Indirect conversion flat panel detectors have a scintillator layer which converts x-ray photons to photons of visible light and utilise a photo diode matrix of amorphous silicon to subsequently convert the light photons into an electrical charge. This charge is proportional to the number and energy of x-ray photons interacting with the detector pixel and therefore the amount and density of material that has absorbed the x-rays. Direct conversion flat panel detectors use a photo conductor like amorphous selenium (a-Se) or Cadmium telluride (Cd-Te) on a multi-micro electrode plate, providing the greatest sharpness and resolution. The information on both types of detectors is read by thin film transistors. In the direct conversion process, when x-ray photons impact over the photo conductor, like amorphous Selenium, they are directly converted to electronic signals which are amplified and digitised. As there is no scintillator, lateral spread of light photons is absent here, ensuring a sharper image. This differentiates it from indirect construction.

PRINCIPLES OF X-RAY TECHNOLOGY IN MEDICAL IMAGING AND IMPROVEMENT OF RADIOLOGICAL IMAGES (2nd Part)

Radioisotopes are unstable nuclei of elements (eg Molybdenum 99), which are transformed into stable nuclei while emitting radiation (particles, photons). This phenomenon is characterized as radioactivity. Radioactivity can be natural or artificial. Artificial radioactivity is that observed in isotopes produced artificially in a laboratory. The study of radioactive isotopes in combination with the development of systems for the detection of emitted radiation, was the trigger for the investigation of possible applications of radioisotopes in medicine. This research resulted in the creation of a new science, Nuclear Medicine, whose main purpose is to apply the properties of radioisotopes in the diagnosis and treatment of human diseases.

PRINCIPLES OF X-RAY TECHNOLOGY IN MEDICAL IMAGING AND IMPROVEMENT OF RADIOLOGICAL IMAGES (1st Part)

The X-ray tube is one of the most important components in any X-ray system. In the beginning, physicists and physicians used gas ion tubes. The so-called Coolidge tube applied a high vacuum and is still used today. Medical examinations have required continuously improved designs of X-ray tubes (smaller focal spots at a higher output). The principle of the Goetze line focus is still applied in any diagnostic X-ray tube. Different anode materials and the rotating anode contributed to an increased output and reduced exposure time. Bearings needed special attention. Spiral groove bearings are the most advanced design today. The heat storage capacity of the anode and the tube housing assembly influences examination time and patient throughput. Cardiac imaging required less motion blurring in cine film images and increasing radiation exposure in interventional procedures calling for measures to reduce dose. Protection against radiation and electric shock has always been a concern of design engineers. Focal spot sizes dedicated to specific applications and heat management within the total tube housing assembly will be future issues. Even in the event of ultrasound and MR technology, X-ray procedures will still be applied for diagnostic and interventional purposes.

PRINCIPLES OF MAGNETIC RESONANCE TECHNOLOGY IN MEDICAL IMAGING OF NON IONIZATION IMAGES

The X-ray tube is one of the most important components in any X-ray system. In the beginning, physicists and physicians used gas ion tubes. The so-called Coolidge tube applied a high vacuum and is still used today. Medical examinations have required continuously improved designs of X-ray tubes (smaller focal spots at a higher output). The principle of the Goetze line focus is still applied in any diagnostic X-ray tube. Different anode materials and the rotating anode contributed to an increased output and reduced exposure time. Bearings needed special attention. Spiral groove bearings are the most advanced design today. The heat storage capacity of the anode and the tube housing assembly influences examination time and patient throughput. Cardiac imaging required less motion blurring in cine film images and increasing radiation exposure in interventional procedures called for measures to reduce dose. Protection against radiation and electric shock has always been a concern of design engineers. Focal spot sizes dedicated to specific applications and heat management within the total tube housing assembly will be future issues. Even with the event of ultrasound and MR technology, X-ray procedures will still be applied for diagnostic and interventional purposes.

ELECTROCARDIOGRAPHY DEFORMATIONS

An electrocardiogram records the electrical signals in the heart. It's a common and painless test used to quickly detect heart problems and monitor the heart's health. An electrocardiogram — also called ECG or EKG — is often done in a health care provider's office, a clinic or a hospital room. ECG machines are standard equipment in operating rooms and ambulances. Some personal devices, such as smartwatches, offer ECG monitoring. Ask your health care provider if this is an option for you.

Effectiveness of a Canal Brush on Removing Smear Layer: A Scanning Electron Microscopic Study

This study evaluated the effectiveness of a highly flexible endodontic brush made of polypropylene canal brush (CanalBrush; Coltène) on smear layer removal from the canal walls when used according to the manufacturer's recommendations. Forty-four single-rooted mandibular incisors were prepared to apical size 30/0.06 and randomly divided into three groups A, B and C, where the final irrigation regimen was 10 mL 17% EDTA and 10 mL 2.5% NaOCl for group A, 10 mL EDTA, 5 mL NaOCl, CanalBrush for 20 s at 450 rpm and 5 mL NaOCl for group B, 10 mL NaOCl, CanalBrush and 10 mL NaOCl for group C. One medium-sized CanalBrush was used for each root canal and all brushes were examined under the optical microscope after application to evaluate bristle deformation. Afterwards, roots were split longitudinally and the presence of smear layer was evaluated under a scanning electron microscope. Used brushes invariably exhibited bristle deformation. Group C exhibited the highest means of smear layer in all thirds. Comparing the apical thirds in all groups, there was no statistical difference between groups A and B (3.64±0.48 and 3.68±0.62 respectively), while group C exhibited significantly higher scores (3.9±0.28) than the other two groups. In conclusion, the CanalBrush proved unable to remove smear layer from the instrumented root canals, when used according to the manufacturers' instructions.

O objetivo deste estudo foi avaliar a eficácia de um escova intra-canal (CanalBrush, Coltène) na remoção da smear layer das paredes do canal radicular, quando usada de acordo com as instruções do fabricante. Quarenta e quatro incisivos mandibulares unirradiculares foram instrumentados até o ápice com instrumentos 30/0.06 e aleatoriamente distribuidos em três grupos A, B e C, com regime de irrigação final de 10 mL a 17% EDTA e 10 mL NaOCl a 2,5% para o Grupo A; irrigação final de 10 mL EDTA, 5 mL NaOCl, uso da escovinha CanalBrush por 20 s a 450 rpm e 5 mL NaOCl para o Grupo B e 10 mL NaOCl, uso da escovinha CanalBrush e 10 mL NaOCl para o Grupo C. Foi utilizada escovinha CanalBrush de tamanho médio para cada canal e todas elas foram examinadas em microscópio para avaliação da deformação de cerdas. Depois as raízes foram cortadas longitudinalmente e a presença da smear layer foi avaliada por microscópio eletrônico de varredura. As escovinhas usadas apresentaram todas alguma deformação das cerdas. No Grupo C foi observada a maior média de área de smear layer em todos os terços dentais. Na comparação dos terços apicais de todos os grupos não houve diferença significativa entre os grupos A e B (3,64±0.48 e 3,68±0,62, respectivamente), enquanto que o Grupo C mostrou escores significativamente mais altos(3,9±0.28) que os outros dois grupos. Concluindo, a escovinha CanalBrush mostrou ser incapaz de remover a smear layer dos canais instrumentados, quando usada de acordo com as instruções do fabricante.