Biological Effects and Medical Applications

Abstract

ABSTRACI RF/microwaves applications in medicine, particularly in cardiology, urology and surgery are described. Several of the applications have gained worldwide acceptance and are presendy used to treat human subjects, while others are curndy being researched and developed. To develop medical applications using RF/Microwaves, known and new biological effects are being thoroughly investigated. The effect of electromagnetic fields on biological materials and systems have been of particular interest RF/MICROWAVES APPLICATIONS IN MEDICINE INTRODUCTI0NThe use of RE/microwaves in therapeutic medicine has increased dramatically in the last few years. RF and microwave therapies for cancer in humans are well documented, and are presently used in many cancer centers. RF treatments for supraventricular arrhythmias, and more recently for ventricular tachycardia (VT) are currently employed by major hospitals. RF/microwaves are also used in human subjects for the treatnent of benign prostatic hyperplasia (BPH), and have gained international approval, including approval by the United States Food and Drug Administration (FDA). Despite these advances, considerable efforts are being expended on the improvement of such medical device technology.Furthermore, new modalities such as microwave enhanced liposuction, microwave ablation, RF/microwaves for the enhancement of drug absorption and microwave wound sterilizaton are continually being researched. In this paper we specifically adress the advances in the area of RE/microwave ablation, RF/microwave treatment of benign prostatic hyperplasia, microwave balloon angioplasty and two new areas of investigation: microwave enhanced liposuction and microwave anastomoses. RF/MICROWAVE ABLATION (115)Cardiac arrhythmias can result from a variety of clinical conditions, but at their root is an abnormal focus, or pathway, of electrical activity. Abnormal sources of electrical activity most commonly occur at or above the AV-node, and are thus deened supraventricular tachy-arrhythmias. Altematively, abnormal ventricular foci cause ventricular tachycardia. The presence of abnormal conduction pathways can also result in an uncontrolled cycling of electrical activity resulting from retrograde signal conduction through the myocardium (re-entry tachy-arrhytmnias). Re-entry can occur within the AVnode (AVNRT), or via accessory conduction pathways (AP). Regardless of the specific etiology, once the source of the arrhythmia has been identified, destruction of the abnormal cardiac tissue is curative. Various energy forms have been used to create such localized tissue injury, including direct current (DC), radio-frequency (RF), and microwave energy.The clinical use of DC ablation dates back to 1982. An electrode catheter is placed at the desired location, and a DC shock is applied. Although complete ablation occurs in up to 65% of patients, DC ablation is fraught with complications. Hypotension, perforation, cardiac tamponade, embolization, pericarditis, and ventricular tachy-arrhythmias have been reported ...

Stone Axe Technology in Neolithic South India: New Evidence from the Sanganakallu-Kupgal Region, Mideastern Karnataka

“…It does seem relevant to note, however, that this was a time when small amounts of decorative copper and gold-present in low frequencies at other Southern Neolithic sites (see Korisettar et al 2001;Wheeler 1948)-were first appearing as exotic long-distance trade items in the Sanganakallu-Kupgal region. There are examples from the archaeological record of stone tool production systems becoming more complex in areas that overlapped with metal-producing communities and/or where tools and objects of metal were becoming available through exchange networks; for example, the elaborate flint "skeuomorphs" of bronze daggers in Late Neolithic Scandinavia (Lubbock 1869;Stafford 2003; see also Rosen 1997 for a Near Eastern perspective). One hypothesis we are therefore exploring is that the infiltration of highly valued and probably symbolically laden metal items during the Late Neolithic period led to a major increase in the production of dolerite axes for exchange in South India, including elaborately manufactured and possibly status-linked Method 1 forms.…”

Disappeared by Climate Change. The Shepherd Cultures of Qulban Ceni Murra (2nd Half of the 5th Millennium bc) and their Aftermath

“…While the Qulban Beni Murra Late Chalcolithic/EB cairn fields are by far -due to their "megalithism index" SCHMIDT 1996, ROSEN 1997, and QUINTERO et al 2002. STEKELIS 1944 investigated a sample of fan scrapers from Qulban Beni Murra, which he related to a similar industry he identified as Neolithic and called Kilwian from the Achatberg of Jabal Tubayk (cf.…”

“…And, possibly it is too simplistic to expect a one-way development towards oases economies 17. SCHMIDT 1996;ROSEN 1997. L. A. Quintero, P. J. Wilke and G. O Rollefson reported recently on the long-sought quarries and production centres for fan scraper blanks and large percussion blades near al-Jafr; 79 recorded sites including large quarries over 12 ha in the area, and three trench mines (QUINTERO et al 2002) 23.…”