Saddle antenna radio frequency ion sources.

Existing RF ion sources for accelerators have specific efficiencies for H(+) and H(-) ion generation ∼3-5 mA/cm(2) kW, where about 50 kW of RF power is typically needed for 50 mA beam current production. The Saddle Antenna (SA) surface plasma source (SPS) described here was developed to improve H(-) ion production efficiency, reliability, and availability. In SA RF ion source, the efficiency of positive ion generation in the plasma has been improved to 200 mA/cm(2) kW.

Compact surface plasma H⁻ ion source with geometrical focusing.

Factors limiting operating lifetime of a Compact Surface Plasma Sources (CSPS) are analyzed and possible treatments for lifetime enhancement are considered. Increased cooling permeate increased discharge power and increased beam intensity and duty factor. A design of an advanced CSPS with geometrical focusing of H(-) flux is presented.

Monoenergetic proton beams accelerated by a radiation pressure driven shock.

We report on the acceleration of impurity-free quasimononenergetic proton beams from an initially gaseous hydrogen target driven by an intense infrared (λ=10 μm) laser. The front surface of the target was observed by optical probing to be driven forward by the radiation pressure of the laser. A proton beam of ∼MeV energy was simultaneously recorded with narrow energy spread (σ∼4%), low normalized emittance (∼8 nm), and negligible background.

Spallation neutron source saddle antenna H- ion source project.

In this project we are developing an H(-) source which will synthesize the most important developments in the field of negative ion sources to provide high current, high brightness, good lifetime, high reliability, and high power efficiency. We describe two planned modifications to the present spallation neutron source external antenna source in order to increase the plasma density near the output aperture: (1) replacing the present 2 MHz plasma-forming solenoid antenna with a 13 MHz saddle-type antenna and (2) replacing the permanent multicusp magnetic system with a weaker electromagnet.

Electron acceleration by few-cycle laser pulses with single-wavelength spot size.

Generation of relativistic electrons from the interaction of a laser pulse with a high density plasma foil, accompanied by an underdense preplasma in front of it, has been studied with two-dimensional particle-in-cell (PIC) simulations for pulse durations comparable to a single cycle and for single-wavelength spot size. The electrons are accelerated predominantly in forward direction for a preplasma longer than the pulse length. Otherwise, both forward and backward electron accelerations occur.

[Clinical characteristics of acute cholecystitis in males].

The analysis of 682 case histories of males suffering from acute cholecystitis suggested a conclusion on occasional deviations in clinical manifestations of the disease in males. Various combinations of complications are not a rare finding making the diagnosis problematic. Acute destructive process in the gall bladder occurs in the presence of chronic inflammatory and infiltrative alterations in the hepatopancreatoduodenal area.

[Acute cholecystitis in the early postoperative period].

The authors observed 6 patients, who developed acute cholecystitis at day 2--5 after the operation. In 3 patients, an operation on the abdominal organs was performed, in 3--the urologic intervention. The leading symptoms of postoperative cholecystitis are the following: epigastric pain, stable intestinal paresis, high body temperature.

[Role of a microbial factor, necrotic tissue and a foreign body in the development of wound suppuration].

The effect of microorganisms, necrotic tissues and a foreign body on the development of festering process in rat wounds was studied. It was found that the presence of necrotic tissues is the necessary and sufficient condition for a clinical manifestation of infection in rat wounds. Additional infection of the wounds and introduction of a foreign body did not appreciably change the clinical picture.

[Potentials of a scanning electron microscopic method in studying dressing materials].

The possibilities of the scanning electron microscopy (SEM) technique were evaluated in the studies of functional properties of dressing materials. It was shown that the use of SEM enables the disclosing of the effect of structural characteristics of the dressing materials on their atraumaticity, the appraisal of the absorption capacity of the dressings, and the exploration of the time course of wound healing under the dressings.

[Autoradiographic and electron microscopic studies of the effect of Soviet dressing materials on experimental wound healing].

Autoradiography and scanning electron microscopy were-used to assess new Soviet dressing materials in experiments on rats. It was shown that the two-layer nonwoven atraumatic material, caproic gauze, a modified surface active agent and kombutek-11 exert favourable effects on the regenerative processes in the wounds and promote more rapid wound healing as compared with a conventional cotton-gauze bandage. It is advisable to devise dressing materials possessing wound-healing action similar to kombutek-11.

[Evaluation of the atraumatic properties f bandage material].

Experiments were made to examine atraumatic properties of 3 samples of dressing material. A dressing made of cotton wool and gauze served as control. It was shown that atraumatic properties of dressing material can be reliably evaluated by cytological examination of wound prints.

[Repair processes in wound tissues of experimental animals following administration of glycine].

A study was made of the effect of glycine given in doses approximating the physiological ones on the repair of processes in rat wound tissues. It was disclosed that in the early periods of wound healing, glycine administration leads to the increased content of cAMP and cAMP/cGMP ratio in the wound muscle and then in the granulation tissue, which appears to promote the intensification of the repair processes manifesting in the changes in tissue metabolism (DNA, collagen), in anti-inflammatory action, as well as in a more rapid maturation of the granulation tissue and wound reduction. It was also found that the doses of glycine tested do not affect the content of insulin and hydrocortisone in the blood of experimental animals.

[Effect of imidazole on collagenogenesis in granulation tissue of experimental wounds].

A study was made of the effect of imidazole on wound healing. The duration of wound healing was 2 days less in animals given imidazole as compared to controls, with the rate of prolin-containing protein synthesis by fibroblast and the rate of their egress into the intercellular space being increased. No excess fibrillogenesis was noted.

[Morphologic and biochemical study of stimulated collagenogenesis].

A study was made of the effect of potassium orotate on wound healing. The duration of wound healing was 3 days less in animals given potassium orotate as compared to controls, with the rate of prolin-containing protein synthesis by fibroblasts and the rate of their egress into the intercellular space being increased. No excess fibrillogenesis was noted.