home r38 r39 r1 r2 r3 The Ripoll is a river in the comarca of Vallès Occidental, Catalonia, Spain. It covers the vast majority of the shire, crossing it from north to south, and flows into the river Besòs, near Barcelona.

Contents 1 Geography 2 History 3 1962 disaster 4 See also 5 References 6 External links

Geography

The source of the river is located in the Serra de Granera, at 640 metres (2,100 ft) of elevation, and it discharges in Montcada i Reixac, at 35.5 metres (116 ft). It has a length of 39.5 kilometres (24.5 mi), with a total of 181.5 kilometres (112.8 mi), once its tributaries are included. It covers the vast majority of the comarca of Vallès Occidental, passing through the municipalities of Sant Llorenç Savall, Castellar del Vallès, Sabadell, Barberà del Vallès, Ripollet and Montcada i Reixac. Throughout the comarca, it crosses alluvial clay terrains, which erodes easily, causing the river to carve a deep path into the soil. History

Throughout its history, the river was used by the inhabitants of the surrounding area for irrigation. Irrigation has been in place from at least the mid-10th century, when priests of Sant Llorenç built an irrigation system that is still used to work the orchards along the riverside and mills to produce flour.

As modernization also reached the area, most of the mills were reconverted to produce paper. However, by the 18th century, the production of paper had ceased to be a dominant industry along the river.

During the 19th century, the mills of the riverside were reconverted again, this time into textile factories, which lasted until the late 20th century. Due to the dyes and chemicals used in the textile industry, the water of the river became heavily polluted.

More recently, because of the Catalonian textile crisis, most of the factories were abandoned or reconverted for other uses, lessening the strain on the river's water quality. Recently, there have been initiatives to recover the Ripoll for community recreation, by restoring the river, which had deteriorated due not only to industrial pollution but also to the shanty towns made by immigrants who came to work in the mills from Southern Spain during the 1960s. 1962 disaster The Ripoll in Sabadell during a flood, very common in spring, when the Mediterranean climate suffers torrential rains.

In 1962, the Vallès Occidental suffered a period of strong floods followed by winds that devastated the shire and caused hundreds of deaths. The immigrants from southern Spain who were extremely poor and had settled in the riverside suffered the worst consequences. See also List of rivers of Catalonia

Cardiac imaging and Ripoll River

Cardiac imaging techniques include coronary catheterization, echocardiogram, and Intravascular ultrasound.

Contents 1 Indications 2 Coronary catheterization 3 Echocardiogram 4 Intravascular ultrasound 5 Positron emission tomography 6 Computed tomography angiography 7 Magnetic resonance imaging 8 References

Indications

A physician may recommend cardiac imaging to support a diagnosis of a heart condition.

Medical specialty professional organizations discourage the use of routine cardiac imaging during pre-operative assessement for patients about to undergo low or mid-risk non-cardiac surgery because the procedure carries risks and is unlikely to result in the change of a patient's management. Coronary catheterization

Coronary catheterization uses pressure monitoring and blood sampling through a catheter inserted into the heart through blood vessels in the leg to determine the functioning of the heart, and, following injections of radiocontrast dye, uses X-ray fluoroscopy, typically at 30 frames per second, to visualize the position and volume of blood within the heart chambers and arteries. Coronary angiography is used to determine the patency and configuration of the coronary artery lumens. Echocardiogram

Transthoracic echocardiogram uses ultrasonic waves for continuous heart chamber and blood movement visualization. In recent times, it has become one of the most commonly used tools in diagnosis of heart problems, as it allows non-invasive visualization of the heart and the blood flow through the heart, using a technique known as Doppler.

Transoesophageal echocardiogram uses a specialized probe containing an ultrasound transducer at its tip is passed into the patient's esophagus. It is used in diagnosis of various thoracic defects or damage, i.e. heart and lung imaging. It has some advantages and disadvantages over thoracic or intravasular ultrasound. Intravascular ultrasound

Intravascular ultrasound, also known as a percutaneous echocardiogram is an imaging methodology using specially designed, long, thin, complex manufactured catheters attached to computerized ultrasound equipment to visualize the lumen and the interior wall of blood vessels. Positron emission tomography

Positron emission tomography (PET), an imaging methodology for positron emitting radioisotopes. PET enables visual image analysis of multiple different metabolic chemical processes and is thus one of the most flexible imaging technologies. Cardiology uses are growing very slowly due to technical and relative cost difficulties. Most uses are for research, not clinical purposes. Appropriate radioisotopes of elements within chemical compounds of the metabolic pathway being examined are used to make the location of the chemical compounds of interest visible in a PET scanner constructed image. Computed tomography angiography

Computed tomography angiography (CTA), an imaging methodology using a ring-shaped machine with an X-Ray source spinning around the circular path so as to bathe the inner circle with a uniform and known X-Ray density. Cardiology uses are growing with the incredible developments in CT technology. Currently, multidetector CT, specially the 64 detector-CT are allowing to make cardiac studies in just a few seconds (less than 10 seconds, depending on the equipment and protocol used). These images are reconstructed using algorithms and software. Great development and growth will be seen in the short term, allowing radiologists to diagnose cardiac artery disease without anesthesia and in a non-invasive way. Magnetic resonance imaging

Magnetic resonance imaging (originally called nuclear magnetic resonance imaging), an imaging methodology based on aligning the spin axis of nuclei within molecules of the object being visualized using both powerful superconducting magnets and radio frequency signals and detectors. Cardiology uses are growing, especially since MRI differentiates soft tissues better than CT and allows for comprehensive exams including the quantitative assessment of size, morphology, function, and tissue characteristics in one single session. Current implementations for Cardiology uses are sometimes limited by lengthy protocols, claustrophobia and contraindications based on some complex metallic implants (pacemakers, defibrillators, insulin pumps), while artificial valves and coronary stents are generally not problematic. Image quality can be reduced by the continuous movement of heart structures. There is a promising future in cardiac MRI by more efficient scans, increasing availability of scanners and more widespread knowledge about its clinical application.