The linear accelerator (linac) is a device that uses highfrequency electromagnetic waves to accelerate charged particles such as electrons to high energies through a linear tube. The high-energy electron beam can be used for treating superficial tumours, or it can be made to strike a target to produce x-rays for treating deep-seated tumours. In the majority of instances, the collimated beam eme...

Heat exchangers play significant role in refrigeration and air conditioning systems. Ongoing research aims to improve, or at least maintain, the system performance while reducing the size, weight and cost of the heat exchangers. This in turn leads to lower system refrigerant charge and reduced environmental impact. Using heat exchangers with small tube diameters (less than 5 mm) instead of larg...

UNLABELLED Tympanostomy tube (TT) insertion is one of the most frequently performed procedures in otolaryngology. Otorrhea, tympanosclerosis, retraction, perforation, and cholesteatoma are complications reported in the literature after its application. AIM To determine the incidence and the type of TT insertion sequelae/complications in children presenting with recurrent otitis media and chro...

Received for publication 12 July 1968. ashed in a muffle furnace at 600'C for at least three hours. Of the acid ammonium sulphate, 10 ml, and 30 ml of water are added to the ashed sample, and after warming to dissolve soluble material the contents are decanted with washing into a 50 ml centrifuge tube, the BaSO4 being washed into the tube as far as possible. The tube is centrifuged for 5 min, t...

Headphones and earphones have many extremely small holes or narrow slits; they use sound-absorbing or porous material (i.e., dampers) to suppress vibratory system resonance. The air viscosity in these acoustic paths greatly affects the acoustic properties. Simulation analyses such as the finite element method (FEM) therefore require knowledge of the material properties of sound-absorbing or por...

The function of the esophagus, the first organ of the digestive tube, appears very simple: it is an anteroposteriorly flattened hollow tube organ that transports material from the mouth into the stomach. However, this requires a very complex swallowing mechanism, lubrication of the swallowed material with saliva and other esophageal secretions, transport into the stomach by peristaltic waves, a...

Earphones and headphones, which are compact electro-acoustic transducers, tend to have a lot of acoustic absorption materials and porous materials known as dampers, which often have a large number of extremely small holes and narrow slits to inhibit the resonance of the vibrating system, because the air viscosity significantly affects the acoustic characteristics in such acoustic paths. In orde...

OBJECTIVE To prospectively evaluate image quality and radiation dose using a low-dose computed tomography angiography protocol and iterative image reconstruction for high-pitch dual-source CT-angiography (DSCTA) of the supraaortic arteries. MATERIAL AND METHODS DSCTA was performed in 42 patients, using either 120 kVp tube voltage, 120 mAS tube current, 2.4 pitch and filtered back projection, ...

UNLABELLED Tracheal secretion leakage might lead to ventilator-associated pneumonia. Standard tracheal tube cuffs are cylindrical in shape. Bronchial tree aspiration is observed in the presence of leakage past tracheal tube cuffs. The new TaperGuard tracheal tube has a cuff in the shape of a cone, preventing from the development of microtubules and microaspiration. The aim of the study was to c...