Suppressed ion-scale turbulence in a hot high-β plasma.

An economic magnetic fusion reactor favours a high ratio of plasma kinetic pressure to magnetic pressure in a well-confined, hot plasma with low thermal losses across the confining magnetic field. Field-reversed configuration (FRC) plasmas are potentially attractive as a reactor concept, achieving high plasma pressure in a simple axisymmetric geometry. Here, we show that FRC plasmas have unique, beneficial microstability properties that differ from typical regimes in toroidal confinement devices.

Diagnostic suite of the C-2U advanced beam-driven field-reversed configuration plasma experiment.

The C-2U experiment at Tri Alpha Energy studies the evolution of field-reversed configuration (FRC) plasmas sustained by neutral beam injection. Data on the FRC plasma performance are provided by a comprehensive suite of diagnostics that includes magnetic sensors, interferometry, Thomson scattering, spectroscopy, bolometry, reflectometry, neutral particle analyzers, and fusion product detectors. While many of these diagnostic systems were inherited from the preceding experiment C-2, C-2U has a variety of new and upgraded diagnostic systems: multi-chord far-infrared polarimetry, multiple fast imaging cameras with selectable atomic line filters, proton detector arrays, and 100 channel bolometer units capable of observing multiple regions of the spectrum simultaneously.

Multi-channel Doppler backscattering measurements in the C-2 field reversed configuration.

A versatile heterodyne Doppler Backscattering (DBS) system is used to measure density fluctuation levels (in the wavenumber range kρs ≤ 50), and the toroidal E × B flow velocity in the C-2 Field-Reversed Configuration (FRC). Six tunable frequencies in three waveguide bands (26 GHz ≤ f ≤ 90 GHz) are launched using monostatic beam optics, via a quasi-optical beam combiner/polarizer and an adjustable parabolic focusing mirror (inside the vacuum enclosure) achieving Gaussian beam spot sizes of 3-5.5 cm at the X/O-mode cutoff.

Overview of C-2 field-reversed configuration experiment plasma diagnostics.

A comprehensive diagnostic suite for field-reversed configuration (FRC) plasmas has been developed and installed on the C-2 device at Tri Alpha Energy to investigate the dynamics of FRC formation as well as to understand key FRC physics properties, e.g., confinement and stability, throughout a discharge.

Far infrared laser polarimetry and far forward scattering diagnostics for the C-2 field reversed configuration plasmas.

A two-chord far infrared (FIR) laser polarimeter for high speed sub-degree Faraday rotation measurements in the C-2 field reversed configuration experiment is described. It is based on high power proprietary FIR lasers with line width of about 330 Hz. The exceptionally low intrinsic instrument phase error is characterized with figures of merit.

Magnetic diagnostic suite of the C-2 field-reversed configuration experiment confinement vessel.

Magnetic measurements are a fundamental part of determining the size and shape of field-reversed configuration (FRC) plasmas in the C-2 device. The magnetic probe suite consists of 44 in-vessel and ex-vessel probes constructed using various technologies: ultra-high vacuum compatible mineral-insulated cable, nested triple axis coils hand-wound on ceramic bobbins, and commercial chip inductors mounted on printed circuit boards. Together, these probes measure the three-dimensional excluded flux profile of the FRC, which approximates the shape of the separatrix between the confined plasma volume and the scrape-off layer.

Internal magnetic field measurement on C-2 field-reversed configuration plasmas.

A long-lived field-reversed configuration (FRC) plasma has been produced in the C-2 device by dynamically colliding and merging two oppositely directed, highly supersonic compact toroids (CTs). The reversed-field structure of the translated CTs and final merged-FRC state have been directly verified by probing the internal magnetic field structure using a multi-channel magnetic probe array near the midplane of the C-2 confinement chamber. Each of the two translated CTs exhibits significant toroidal fields (B(t)) with opposite helicity, and a relatively large B(t) remains inside the separatrix after merging.

Field reversed configuration confinement enhancement through edge biasing and neutral beam injection.

Field reversed configurations (FRCs) with high confinement are obtained in the C-2 device by combining plasma gun edge biasing and neutral beam injection. The plasma gun creates an inward radial electric field that counters the usual FRC spin-up. The n = 2 rotational instability is stabilized without applying quadrupole magnetic fields.

Doppler spectroscopy and D-alpha emission diagnostics for the C-2 FRC plasma.

Two Doppler spectroscopy diagnostics with complementary capabilities are developed to measure the ion temperatures and velocities of FRC plasmas in the C-2 device. First, the multichord ion doppler diagnostic can simultaneously measure 15 chords of the plasma using an image intensified camera. Second, a single-chord fast-response ion Doppler diagnostic provides much higher faster time response by using a 16-channel photo-multiplier tube array.

Two-color CO2/HeNe laser interferometer for C-2 experiment.

A six-channel two-color interferometer has been developed for plasma electron density measurements in the C-2 field reversed configuration experiment. A CO(2) laser is utilized as the main probe beams, while copropagating visible HeNe laser beams are mainly sensitive to vibration. Density measurements in C-2 plasmas have shown that this is a reliable turn-key system.

Dynamic formation of a hot field reversed configuration with improved confinement by supersonic merging of two colliding high-β compact toroids.

A hot stable field-reversed configuration (FRC) has been produced in the C-2 experiment by colliding and merging two high-β plasmoids preformed by the dynamic version of field-reversed θ-pinch technology. The merging process exhibits the highest poloidal flux amplification obtained in a magnetic confinement system (over tenfold increase). Most of the kinetic energy is converted into thermal energy with total temperature (T{i}+T{e}) exceeding 0.

Nested polymerase chain reaction strategy simultaneously targeting DNA sequences of multiple bacterial species in inflammatory joint diseases. II. Examination of sacroiliac and knee joint biopsies of patients with spondyloarthropathies and other arthritides.

Objective: Bacteria play a crucial pathogenetic role in reactive arthritis (ReA) and other forms of spondyloarthropathy (SpA) and in Lyme arthritis. Although there is evidence of local persistence of bacterial antigens no definitive method revealing microbes in peripheral joints has been established. We detected DNA of individual bacteria in synovial material by PCR.

Nested polymerase chain reaction strategy simultaneously targeting DNA sequences of multiple bacterial species in inflammatory joint diseases. I. Screening of synovial fluid samples of patients with spondyloarthropathies and other arthritides.

Objective: Bacteria play a crucial pathogenetic role in Lyme arthritis (LA), reactive arthritis (ReA), other forms of spondyloarthropathy (SpA), and possibly in undifferentiated oligoarthritis (uOligo). Polymerase chain reaction (PCR) technology has been applied to detect bacterial DNA of individual microbes in synovial fluid (SF) of patients with arthritides. We screened for DNA sequences of 8 bacterial species simultaneously in SF of patients with inflammatory joint disease.

[Surgical treatment of idiopathic megacolon].

The authors discuss own experience in diagnosis and surgical treatment of 32 patients with idiopathic megacolon. Three surgical techniques were compared: 1) partial excision of the colon, 2) nearly complete excision of the colon with cecum-rectal anastomosis, and 3) total colectomy with ileorectal anastomosis. Basing on the authors' own experience and available literature the third approach is recommended as the most appropriate in the treatment of the persistent, chronic constipation accompanying idiopathic megacolon.

[Comparative evaluation of tensile strength of absorbable threads Dexon and Maxon. Experimental studies].

This paper submits strength tests on Dexon and Maxon resorbable sutures at the knot and without a knot, the breaking resulting from hydrolysis. The tests were performed on rats, by comparing Maxon monofilament suture with Dexon woven suture. The dissections were done 3, 7, 21 and 42 days after the implantation.

[Evaluation of the analgesic effectiveness of tramadol hydrochloride in surgical practice].

Tramadol hydrochloride was administered to: a) 90 patients who underwent various abdominal surgery (group A) immediately after operation; b) 50 patients with inoperable tumors of pharynx, stomach, pancreas, liver and biliary tract and colon (group B); c) 32 patients in surgical out-patient clinic (group C). Excellent and favourable results (group A - 87.8%; group B - 74%, and group C - 75%) and negligible adverse reactions advocate the use of tramadol hydrochloride both in in- and out-patient surgical clinics as an effective analgesic agent.

Long-term results of jejunoileostomy for extreme obesity.

The results of jejunoileostomy performed on 130 extremely obese patients in 1972-1982 are presented. The mean preoperative body weight was 130.9 kg.

[Morphological assessment of the adaptation process in the small intestine after jejunoileostomy for extreme obesity].

The paper presents the author's experiments performed for examining the morphological adaptation in the intestinal loop, preserved for the food passage after jejunoileostomy for extreme obesity. Macro-, micro-, and ultramicroscopic examinations were carried out in 20 patients. A characteristic elongation and hypertrophy of the active intestinal loop, thickening of its wall (especially mucosa), hypertrophy and elongation of the intestinal villi as well as reduction of the mucous cells could be observed.