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Fusion power has been increased by a factor of 3 in DIII-D by tailoring the pressure profile to avoid the kink instability in H-mode plasmas. The resulting plasmas are found to have neoclassical ion confinement. This reduction in transport losses in beam-heated plasmas with negative central shear is correlated with a dramatic reduction in density fluctuations. Improved magnetohydrodynamic stability is achieved by controlling the plasma pressure profile width. In deuterium plasmas the highest gain Q (the ratio of fusion power to input power), was 0.0015, corresponding to an equivalent Q of 0.32 in a deuterium-tritium plasma. © 1996 The American Physical Society.

Routine tritium operation in TFTR has permitted investigations of alpha particle physics in parameter ranges resembling those of a reactor core. ICRF wave physics in a DT plasma and the influence of isotopic mass on supershot confinement have also been studied. Continued progress has been made in optimizing fusion power production in TFTR, using extended machine capability and Li wall conditioning. Performance is currently limited by MHD stability. A new reversed magnetic shear regime is being investigated with reduced core transport and a higher predicted stability limit.

TFTR has begun its campaign to study deuterium-tritium fusion under reactor-like conditions. Variable amounts of deuterium and tritium neutral beam power have been used to maximize fusion power, study alpha heating, investigate alpha particle confinement, and search for alpha driven plasma instabilities. Additional areas of study include energy and particle transport and confinement, ICRF heating schemes for DT plasmas, tritium retention, and fusion in high βp plasmas. The majority of this work is done in the TFTR supershot confinement regime. To obtain supershots, extensive limiter conditioning using helium fueled ohmic discharges and lithium pellet injection into ohmic and neutral beam heated plasmas is performed, resulting in a low recycling limiter. The relationship between recycling and core plasma confinement has been studied by using helium, deuterium and high-Z gas puffs to simulate high recycling limiter conditions. These studies show that confinement in TFTR supershots is very sensitive to the influx of neutral particles at the plasma edge. © 1995, All rights reserved.

Three campaigns, prior to July 1994, attempted to increase the fusion power in DT plasmas on the Tokamak Fusion Test Reactor (TFTR). The first campaign was dedicated to obtaining >5 MW of fusion power while avoiding MHD events similar to the JET X-event. The second was aimed at producing maximum fusion power irrespective of proximity to MHD limits, and achieved 9 MW limited by a disruption. The third campaign increased the energy confinement time using lithium pellet conditioning while raising the ratio of alpha heating to beam heating.

The Tomamak Fusion Test reactor has performed initial high-power experiments with the plasma fueled with nominally equal densities of deuterium and tritium. Compared to pure deuterium plasmas, the energy stored in the electron and ions increased by ∼20%. These increases indicate improvements in confinement associated with the use of tritium and possibly heating of electrons by α particles created by the D-T fusion reactions. © 1994 The American Physical Society.

Peak fusion power production of 6.2±0.4 MW has been achieved in TFTR plasmas heated by deuterium and tritium neutral beams at a total power of 29.5 MW. These plasmas have an inferred central fusion alpha particle density of 1.2×1017 m-3 without the appearance of either disruptive magnetohydrodynamics events or detectable changes in Alfvén wave activity. The measured loss rate of energetic alpha particles agreed with the approximately 5% losses expected from alpha particles which are born on unconfined orbits. © 1994 The American Physical Society.

The final hardware modifications for tritium operation have been completed for the Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. These activities include preparation of the tritium gas handling system, installation of additional neutron shielding, conversion of the toroidal field coil cooling system from water to a Fluorinert™ system, modification of the vacuum system to handle tritium, preparation, and testing of the neutral beam system for tritium operation and a final deuterium-deuterium (D-D) run to simulate expected deuterium-tritium (D-T) operation. Testing of the tritium system with low concentration tritium has successfully begun. Simulation of trace and high power D-T experiments using D-D have been performed. The physics objectives of D-T operation are production of ≈ 10 MW of fusion power, evaluation of confinement, and heating in deuteriumtritium plasmas, evaluation of α-particle heating of electrons, and collective effects driven by alpha particles and testing of diagnostics for confined a particles. Experimental results and theoretical modeling in support of the D-T experiments are reviewed. © 1994 American Institute of Physics.

A community survey was conducted examining the differences in levels of psychological distress and its symptomatology, comparing 110 Ethiopian-Jewish and 400 Russian-Jewish immigrants to Israel. Psychological distress was measured by the Talbieh Brief Distress Inventory. Russian immigrants were found to be more distressed than their Ethiopian counterparts and this between-group difference can be attributed to the greater relative number of females, older immigrants and those with longer duration of stay in Israel in the Russian sample. The highest levels of distress were observed for paranoid ideation in the Ethiopian sample and anxiety and hostility in the Russian sample. These symptoms were independent of gender and time since immigration. Russians with longer duration of stay demonstrated higher scores signifying adjustment difficulties than their Ethiopian counterparts. These results suggest that the differences in levels and symptom expression of psychological distress are determined, to a considerable extent, by demographic factors (sex, age) and the differing cultural backgrounds of the two immigrant groups.

Objective: To compare clinical characteristics and outcomes in patients undergoing excision of polypropylene urogynaecological mesh for pain, mesh exposure or both. Design: Prospective, longitudinal cohort. Setting: Academic tertiary referral centre. Population: Women undergoing complete vaginal mesh excision for mesh exposure and/or pain. Methods: Clinical and patient‐reported outcomes assessing pain (visual analog scale, VAS), bother (Pelvic Floor Distress Inventory, PFDI) and functional impact (Pelvic Functional Impact Questionnaire, PFIQ) were collected at baseline, 6, 12 and 24 months after complete mesh excision. Outcomes were compared by mesh type (sling, prolapse [transvaginal or sacrocolpopexy mesh], both) and complication (pain, exposure, both). Main outcome measures: 'Much better' or 'Very much better' on Patient Global Impression of Improvement (PGI‐I) up to 2 years after removal. Results: Of 173 women, 48 underwent removal for pain, 27 for exposure and 98 for exposure plus pain. 'Moderate to severe' baseline symptoms were reported by 75%; the most prevalent and severe symptom was dyspareunia. Patients with pain alone were most bothered (PFDI median 234.2, interquartile range 83, P = 0.02) and had the highest functional impact (PFIQ median 181, interquartile range 138, P < 0.001). After excision, only 33.3% of women with pain alone reported 'improved' symptoms (PGI‐I), versus 73.9% with exposure, 58.3% with exposure plus pain (P = 0.03) with no differences in PGI‐I by mesh type. VAS scores decreased in all groups, but PFDI and PFIQ did not improve in pain patients. Conclusions: In women experiencing a pain complication after urogynaecological mesh insertion, mesh removal often does not improve symptoms. Only 33% of women with pain complications have improved symptoms after urogynaecological mesh removal. Only 33% of women with pain complications have improved symptoms after urogynaecological mesh removal. [ABSTRACT FROM AUTHOR]

Background Familial hypercholesterolemia (FH) is an under-diagnosed condition. Aim We applied standard laboratory criteria across a large longitudinal electronic medical record database to describe cross-sectional population with possible FH. Methods A cross-sectional study of Clalit Health Services members. Subjects who met the General Population MED-PED laboratory criteria, excluding: age <10 years, documentation of thyroid, liver, biliary or autoimmune diseases, a history of chronic kidney disease stage 3 or greater, the presence of urine protein >300 mg/l, HDL-C>80 mg/dl, active malignancy or pregnancy at the time of testing were considered possible FH. Demographic and clinical characteristics are described at time of diagnosis and at a single index date following diagnosis to estimate the burden on the healthcare system. The patient population is also compared to the general population. Results The study cohort included 12 494 subjects with out of over 4.5 million members of Clalit Health Services. The estimated prevalence of FH in Israel was found to be 1:285. These patients are notably positive for, and have a family history of, cardiovascular disease and risk factors. For most of them the LDL-C levels are not controlled, and only a quarter of them are medically treated. Conclusions By using the modified MED-PED criteria in a large electronic database, patients with possible FH can be identified enabling early intervention and treatment. [ABSTRACT FROM AUTHOR]

Consumers demand, in addition to excellent eating quality, high standards of microbial and chemical safety in shelf-stable foods. This requires improving conventional processing technologies and developing new alternatives such as pressure-assisted thermal processing (PATP). Studies in PATP foods on the kinetics of chemical reactions at temperatures (approximately 100 to 120 °C) inactivating bacterial spores in low-acid foods are severely lacking. This review focuses on a specific chemical safety risk in PATP foods: models predicting if the activation volume value ( Va) of a chemical reaction is positive or negative, and indicating if the reaction rate constant will decrease or increase with pressure, respectively, are not available. Therefore, the pressure effect on reactions producing toxic compounds must be determined experimentally. A recent model solution study showed that acrylamide formation, a potential risk in PATP foods, is actually inhibited by pressure (that is, its Va value must be positive). This favorable finding was not predictable and still needs to be confirmed in food systems. Similar studies are required for other reactions producing toxic compounds including polycyclic aromatic hydrocarbons, heterocyclic amines, N-nitroso compounds, and hormone like-peptides. Studies on PATP inactivation of prions, and screening methods to detect the presence of other toxicity risks of PATP foods, are also reviewed. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the outcome of two legal indications for Compulsory Outpatient Treatment (COT) in Israel (a) as an alternative to compulsory hospitalization (CH) and (b) as a follow-up to CH. Demographic, clinical and legal measurements based on 326 COT orders issued in the Jerusalem and Southern district of Israel were compared according to the two legal provisions for COT contained in the Treatment of Mental Patients Law (1991). The COT order was found to be more effective when used as an alternative to CH (53.1%) than when it was used following CH (38.8%), p = 0.002. In the former case, there were fewer schizophrenic patients, fewer hospitalizations, fewer visits to psychiatric emergency services and longer remissions. Our results point to the influence of the legal indications on the efficacy of the COT order and help define the target population. [ABSTRACT FROM AUTHOR]

A novel gaseous detector, based on parallel-plate gas amplification with a resistive anode and remote readout electrode, is described. The detector is significantly less prone to discharges than other gaseous wireless detectors and unique in its ability to achieve high gain at high counting rates. A local counting rate >5 × 10&sup5; counts/mm²-s at a gas gain of up to 105 has been achieved in a 14 × 14 cm² area detector for diffraction applications. rrhe detector radiation hardness is characterized by the anode accumulated charge >100 Coul/cm². The detector is sealed and its regassing period is estimated to be 5-10 yr. The operating characteristics of the new detector, its spatial resolution, and linearity are described and preliminary X-ray diffraction data are presented. [ABSTRACT FROM AUTHOR]

BACKGROUND: Genetic variation in the alcohol dehydrogenase (ADH) enzyme is associated with an aversion to alcohol and a lower risk of alcoholism among Asians. There is growing evidence of a functional role of the ADH2*2 allele in alcohol-drinking patterns among Jews, who have traditionally exhibited low rates of alcoholism and alcohol-related problems. The mechanism by which this allelic effect is mediated is not yet clearly understood. This study examined the effect of ADH2*2 on alcohol-elimination rates (AER) under experimental conditions. METHODS: Young adult male Jews (N = 109) received an intravenous alcohol infusion; metabolism was measured by using standard breath alcohol concentration tests. A clamping technique was used to achieve and maintain a target breath alcohol concentration of 50 mg/100 ml for a defined time period. The AER at steady state was calculated. The alcohol disappearance rate was also calculated from the descending limb slope. Polymerase chain reaction was used for allelic determination of the ADH2 and ADH3 loci. RESULTS: The mean AER among ADH2*2 carriers was significantly higher (8.09 +/- 1.4 g/hr) than among ADH2*1 homozygotes (7.14 +/- 1.5 g/hr; p = 0.003). Significance was retained on adjustment for potential confounding covariates. The ADH2 allele explains 8.5% of the AER variance in this population. Little AER difference was observed across ADH3 genotype groups. The slope of the descending limb increased with increasing copies of the ADH2*2 allele. CONCLUSIONS: The rate of alcohol elimination is significantly associated with the ADH2 genotype of Jewish males. Evidence for variation in alcohol metabolism across ADH genotypic groups provides support for the role of physiologic protective factors in alcohol drinking and suggests that reduced drinking among Jews may be genetically as well as environmentally determined. We believe that application of the novel 'Indiana clamp' enhances AER measurement accuracy, allowing for detection of hitherto undetectable differences. [ABSTRACT FROM AUTHOR]

Kleptomania--the inability to resist the impulse to steal objects, not for personal use or monetary gain--is currently classified in psychiatric nomenclature as an impulse control disorder. However, some of the principle features of the disorder, which include repetitive intrusion thoughts, inability to resist the compulsion to perform the thievery and the relief of tension following the act, suggest that kleptomania may constitute an obsessive-compulsive spectrum disorder. Kleptomania is commonly under-diagnosed and is often accompanied by other psychiatric conditions, most notably affective, anxiety and eating disorders, and alcohol and substance abuse. Individuals with the disorder are usually referred for treatment due to the comorbid psychiatric complaints rather than kleptomanic behaviour per se. Over the past century there has been a shift from psychotherapeutic to psychopharmacological interventions for kleptomania. Pharmacological management using selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SSRIs) and other antidepressants, mood stabilisers and opioid receptor antagonists, as adjuvants to cognitive-behavioural therapy, has produced promising results. [ABSTRACT FROM AUTHOR]

Background: Jerusalem's psychiatrists expect to encounter, as the millennium approaches, an ever-increasing number of tourists who, upon arriving in Jerusalem, may suffer psychotic decompensation.Aims: To describe the Jerusalem syndrome as a unique acute psychotic state.Method: This analysis is based on accumulated clinical experience and phenomenological data consisting of cultural and religious perspectives.Results: Three main categories of the syndrome are identified and described, with special focus on the category pertaining to spontaneous manifestations, unconfounded by previous psychotic history or psychopathology.Conclusions: The discrete form of the Jerusalem syndrome is related to religious excitement induced by proximity to the holy places of Jerusalem, and is indicated by seven characteristic sequential stages. [ABSTRACT FROM AUTHOR]

Describes the installation of a beam emission spectroscopy (BES) system on the DIII-D tokamak to provide localized density fluctuation measurements for long wavelength plasma turbulent modes which are typically associated with anomalous radial transport. Description of the D-III BES diagnostic system; Isolation of small fluctuation signal; Measurements of turbulence.

Toroidal Alfvén eigenmodes (TAE) have been excited by tangential neutral beam injection in the Tokamak Fusion Test Reactor (TFTR) [Proceedings of the Thirteenth International Conference on Plasma Physics and Controlled Nuclear Fusion Research, 1990, Washington, D.C. (International Atomic Energy Agency, Vienna, 1990), Vol. I, p. 9]. Beam emission spectroscopy (BES) has been used to study the radial structure and the poloidal power spectra of these modes. Radial profiles show a global, standing wave structure with a node near r/a=0.6 and a maximum displacement of about 5–10 mm. The cross-phase profiles and the power spectra both imply that the mode is composed of a mixture of components with various poloidal and toroidal mode numbers, as expected for the TAE. Measurements of the poloidal mode spectrum via BES show good agreement with theoretical simulations performed by a nonvariational, kinetic magnetohydrodynamics stability code (nova-k [Cheng, Phys. Rep. 211, 1 (1992)]). In particular, the dominant harmonics in the poloidal spectrum obey the expected relation m+1/2≊q(r)n. [ABSTRACT FROM AUTHOR]

Toroidal Alfvén eigenmodes (TAE) were excited by the energetic neutral beam ions tangentially injected into plasmas at low magnetic field in the Tokamak Fusion Test Reactor (TFTR) [Proceedings of the 11th International Conference on Plasma Physics and Controlled Fusion Research (IAEA, Vienna, 1987), Vol. 1, p. 51]. The injection velocities were comparable to the Alfvén speed. The modes were identified by measurements from Mirnov coils and beam emission spectroscopy (BES). TAE modes appear in bursts whose repetition rate increases with beam power. The neutron emission rate exhibits sawtoothlike behavior and the crashes always coincide with TAE bursts. This indicates ejection of fast ions from the plasma until these modes are stabilized. The dynamics of growth and stabilization were investigated at various plasma currents and magnetic fields. The results indicate that the instability can effectively clamp the number of energetic ions in the plasmas. The observed instability threshold is discussed in light of recent theories. In addition to these TAE modes, intermittent oscillations at three times the fundamental TAE frequency were observed by Mirnov coils, but no corresponding signal was found in BES. It appears that these high-frequency oscillations do not have a direct effect on the plasma neutron source strength. [ABSTRACT FROM AUTHOR]

Previous studies of plasma microturbulence have indicated that the fluctuation power scales with radial wave number, k[sub ⊥], like k[sup -2, sub ⊥ → k[sup -3.5, sub ⊥] for k[sub ⊥] > 2 cm[sup -1]. This implies that low k fluctuations may dominate the spectrum. Beam emission spectroscopy (BES) has been developed to provide spatially localized measurements of density fluctuations in this low k region of the spectrum (k[sub ⊥] <2 cm[sup -1]). A 20-channel system has been installed on TFTR which images one of the heating neutral beams (via fiber optics) onto a set of photoconductive photodiode detectors. Fluctuations in the fluorescent D[sub α] emission from the beam can be related to the local plasma density fluctuations via a model of the atomic excitation processes. The analysis of BES data utilizes many of the standard statistical analysis techniques such as power spectra, coherency and cross phase, and correlation analysis which are also used in the analysis of, for example, Langmuir probe data. In the case of BES however, these techniques require some special modifications to account for systematic effects such as photon statistics and fluctuations in the neutral beam density induced by the strong fluctuations near the plasma edge. [ABSTRACT FROM AUTHOR]

Several experiments have been devised to measure plasma fluctuations in an effort to help elucidate a possible connection between plasma microturbulence and anomalous transport. Results from microwave scattering on the Tokamak Fusion Test Reactor (TFTR) [Nucl. Fusion 18, 1089 (1978)] show that the level of plasma fluctuations increases toward the long-wavelength region (k⊥ρs≤0.2), at which point the fluctuations cannot be spatially resolved. The desire to measure long-wavelength fluctuations has motivated the development of two fluctuation diagnostics, beam emission spectroscopy (BES), and microwave reflectometry on TFTR. BES measures long-wavelength density fluctuations (k⊥≤2 cm-1) by observing the fluorescence emitted from collisionally excited atoms in a TFTR heating beam. In L-mode discharges with relatively flat density profiles, the fluctuations measured with BES are concentrated in the low-frequency region (≤30 kHz). In the laboratory frame, the fluctuations have a poloidal propagation velocity that is approximately equal to that of the plasma rotation, and the frequency spectra are broadened by Doppler effects. Measured fluctuation levels are 5%–10% at the edge of the plasma. In the core, the level falls to less than 1%, which is comparable to observations made with microwave reflectometry and scattering. The fluctuation level in the core (r/a=0.7) is seen to increase with injected beam power, as is observed with microwave scattering at shorter wavelengths (k⊥≊2–10 cm-1). In contrast, the fluctuation level in the edge region does not change significantly with neutral beam power. [ABSTRACT FROM AUTHOR]

The concurrent appearance of the koro syndrome and pathology of the central nervous system is quite rare. A case of a patient with a diagnosed tumour in the genu of the corpus callosum, who displayed typical koro symptoms, is presented. A short series of electroconvulsive shock treatments brought about resolution of the koro symptoms. Neurological investigation of all sporadic cases of koro is deemed necessary, to exclude cerebral involvement. [ABSTRACT FROM AUTHOR]

Studies the confinement and the stability of properties of the DIII-D tokamak high-performance discharges in terms of rotational and magnetic shear. Experimental results obtained from the negative central magnetic shear (NCS); Core transport barrier that forms inside the NCS region; Performance of NCS discharges with strongly peaked pressure profiles.