High-harmonic fast-wave power flow along magnetic field lines in the scrape-off layer of NSTX.

A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast-wave heating and current drive.

Use of the Far Infrared Tangential Interferometer/Polarimeter diagnostic for the study of rf driven plasma waves on NSTX.

A rf detection system for waves in the 30 MHz range has been constructed for the Far Infrared Tangential Interferometer/Polarimeter on National Spherical Torus Experiment (NSTX). It is aimed at monitoring high frequency density fluctuations driven by 30 MHz high harmonic fast wave fields. The levels of density fluctuations at various radial chords and antenna phase angles can be estimated using the electric field calculated by TORIC code and linearized continuity equation for the electron density. In this paper, the experimental arrangement for the detection of rf signal and preliminary results of simulation will be discussed.

Collisional damping of electron bernstein waves and its mitigation by evaporated lithium conditioning in spherical-tokamak plasmas.

The first experimental verification of electron Bernstein wave (EBW) collisional damping, and its mitigation by evaporated Li conditioning, in an overdense spherical-tokamak plasma has been observed in the National Spherical Torus Experiment (NSTX). Initial measurements of EBW emission, coupled from NSTX plasmas via double-mode conversion to O-mode waves, exhibited <10% transmission efficiencies. Simulations show 80% of the EBW energy is dissipated by collisions in the edge plasma. Li conditioning reduced the edge collision frequency by a factor of 3 and increased the fundamental EBW transmission to 60%.

Sheared poloidal flow driven by mode conversion in tokamak plasmas.

A two-dimensional integral full-wave model is used to calculate poloidal forces driven by mode conversion in tokamak plasmas. In the presence of a poloidal magnetic field, mode conversion near the ion-ion hybrid resonance is dominated by a transition from the fast magnetosonic wave to the slow ion cyclotron wave. The poloidal field generates strong variations in the parallel wave spectrum that cause wave damping in a narrow layer near the mode conversion surface. The resulting poloidal forces in this layer drive sheared poloidal flows comparable to those in direct launch ion Bernstein wave experiments.

UPJ Obstruction in the Adult Population: Are Crossing Vessels Significant?

Ureteropelvic junction (UPJ) obstruction describes various causes of impaired drainage at the UPJ. Regardless of the cause, the end result is the same: impedance in the normal flow of urine from the renal pelvis into the proximal ureter, resulting in caliectasis and hydronephrosis. This may lead to progressive deterioration of renal function and, thus, often requires intervention to relieve the obstruction and restore the normal flow of urine. Defining the pertinent anatomy, the degree of obstruction, and differential renal function is key to determining whether and when intervention is necessary.

Dermal tissue fibrosis in patients with chronic venous insufficiency is associated with increased transforming growth factor-beta1 gene expression and protein production.

PURPOSE: Pathologic dermal degeneration in patients with chronic venous insufficiency (CVI) is characterized by aberrant tissue remodeling that results in stasis dermatitis, tissue fibrosis, and ulcer formation. The cytochemical processes that regulate these events are unclear. Because transforming growth factor-beta(1) (TGF-beta(1)) is a known fibrogenic cytokine, we hypothesized that the increased production of TGF-beta(1) would be associated with CVI disease progression. METHODS: Seventy-eight punch biopsy specimens of the lower calf (LC) and the lower thigh (LT) of 52 patients were snap frozen in liquid nitrogen and stratified into four groups according to the Society for Vascular Surgery/International Society for Cardiovascular Surgery CEAP classification (C, clinical; E, etiologic; A, anatomic distribution; and P, pathophysiology). One set of LC biopsy specimens were analyzed for TGF-beta(1) gene expression with quantitative reverse transcriptase-polymerase chain reaction: healthy skin, n = 6; class 4, n = 6; class 5, n = 5; and class 6, n = 7. A second set of biopsy specimens from the LC and LT were analyzed for the amount of bioactive TGF-beta(1) with a certified cell line 64 mink lung epithelial bioassay: healthy skin, n = 8; class 4, n = 23; class 5, n = 13; and class 6, n = 10. The location of TGF-beta(1) was determined at the light and electron microscopy level with immunocytochemistry and immunogold (IMG) labeling. Multiple comparisons were analyzed with a one-way analysis of variance and the Student-Newman-Keuls post hoc tests. The LC and LT comparisons were analyzed with a two-tailed unpaired t test. RESULTS: The TGF-beta(1) gene transcripts for control subjects and patients in classes 4, 5, and 6 were 7.02 +/- 7.33, 43.33 +/- 9.0, 16.13 +/- 7.67, and 7.22 +/- 0.56 x 10(-14) mol/microg total RNA, respectively. The transcripts were significantly elevated in class 4 patients only (P