Novel concept suppressing plasma heat pulses in a tokamak by fast divertor sweeping.

One of the remaining challenges in magnetic thermonuclear fusion is survival of the heat shield protecting the tokamak reactor vessel against excessive plasma heat fluxes. Unmitigated high confinement edge localized mode (ELM) is a regular heat pulse damaging the heat shield. We suggest a novel concept of magnetic sweeping of the plasma contact strike point fast and far enough in order to spread this heat pulse. We demonstrate feasibility of a dedicated copper coil in a resonant circuit, including the induced currents and power electronics. We predict the DEMO ELM properties, simulate heat conduction, 3D particles motion and magnetic fields of the plasma and coil in COMSOL Multiphysics and Matlab. The dominant system parameter is voltage, feasible 18 kV yields 1 kHz sweeping frequency, suppressing the ELM-induced surface temperature rise by a factor of 3. Multiplied by other known mitigation concepts, ELMs might be mitigated enough to ensure safe operation of DEMO.

Non-Kolbe electrolysis of N-protected-α-amino acids: a standardized method for the synthesis of N-protected (1-methoxyalkyl)amines.

Here, we report a standardized method for the synthesis of N-protected (1-methoxyalkyl)amines by the electrochemical decarboxylative α-methoxylation of α-amino acid derivatives using the commercially available, easy-to-use, compact ElectraSyn 2.0 setup. The use of equipment with a standardized power source, electrodes, and other accessories allows this experimental procedure to be easily transferred to any laboratory in the world. A simple workup and chromatography-free purification produced the products in excellent yields above 90%.

High-heat flux ball-pen probe head in ASDEX-Upgrade.

A new high heat flux ball-pen probe head installed on the midplane manipulator is currently being used in ASDEX-Upgrade (AUG). The probe was designed to withstand high heat fluxes making possible the investigation of the plasma edge under harsh conditions, such as low power H-mode. Composed of seven pins (four Langmuir probes, mounted in two Mach probe pairs, and three ball-pen probes), the new probe head allows us to measure several plasma parameters simultaneously and with high temporal resolution. A novel method to correct the sheath potential dynamically accounting for the total secondary electron emission is introduced together with applications to obtain the electron temperature and plasma potential profiles. The total secondary electron emission yield is obtained from particle in cell simulations in AUG condition and probe realistic impact angle with respect to the magnetic field. Finally, the probe capability to investigate turbulence around the separatrix of AUG is discussed.

Filamentary probe on the COMPASS tokamak.

This paper describes a new filamentary probe recently introduced on the COMPASS tokamak. It allows the measurement of electrostatic and magnetic properties of the filaments and their changes in dependence on distance from the separatrix in the region between a divertor and midplane. The probe head is mounted on a manipulator moving the probe radially on a shot-to-shot basis. This configuration is suitable for the long term statistical measurement of the plasma filaments and the measurement of their evolution during their propagation from the separatrix to the wall. The basics of the filamentary probe construction, the evolution of the plasma parameters, and first conditional averages of the plasma filaments in the scrape-off layer of the COMPASS tokamak during the L-mode regime are presented.

Profile measurements of the electron temperature on the ASDEX Upgrade, COMPASS, and ISTTOK tokamak using Thomson scattering, triple, and ball-pen probes.

The ball-pen probe (BPP) technique is used successfully to make profile measurements of the electron temperature on the ASDEX Upgrade (Axially Symmetric Divertor Experiment), COMPASS (COMPact ASSembly), and ISTTOK (Instituto Superior Tecnico TOKamak) tokamak. The electron temperature is provided by a combination of the BPP potential (ΦBPP) and the floating potential (Vfl) of the Langmuir probe (LP), which is compared with the Thomson scattering diagnostic on ASDEX Upgrade and COMPASS. Excellent agreement between the two diagnostics is obtained for circular and diverted plasmas and different heating mechanisms (Ohmic, NBI, ECRH) in deuterium discharges with the same formula Te = (ΦBPP - Vfl)/2.2. The comparative measurements of the electron temperature using BPP/LP and triple probe (TP) techniques on the ISTTOK tokamak show good agreement of averaged values only inside the separatrix. It was also found that the TP provides the electron temperature with significantly higher standard deviation than BPP/LP. However, the resulting values of both techniques are well in the phase with the maximum of cross-correlation function being 0.8.

A modified Katsumata probe--Ion sensitive probe for measurement in non-magnetized plasmas.

A modified Katsumata probe has been developed for measurement of ion velocity distribution function (IVDF) in technological non-magnetized plasmas. A simple construction of the modified Katsumata probe consists of adding a pair of permanent Sm-Co magnets in front of Katsumata probe. A comparative study regarding IVDF measurement in a high power impulse magnetron sputtering system operating in pure argon atmosphere by means of developed modified Katsumata probe and commercially available gridded retarding field analyzer (RFA) has been carried out. A time-resolved measurement of IVDF for two different pressures whilst other plasma conditions have been kept unchanged has revealed that the main advantage of the modified Katsumata probe compared to the RFA consists in significantly smaller angular aperture of entrance orifice of modified Katsumata probe being approximately 15° in comparison with a commercial RFA having angular aperture more than 160°. It leads in much better velocity resolution in measured IVDF since the transversal part of velocity vector is much more suppressed compared to RFA. Furthermore, the modified Katsumata probe less suffers from collisions of ions in the space charge sheath in front or inside of the probe compared to the RFA.

Profile measurements in the plasma edge of mega amp spherical tokamak using a ball pen probe.

The ball pen probe (BPP) technique is used successfully to make profile measurements of plasma potential, electron temperature, and radial electric field on the Mega Amp Spherical Tokamak. The potential profile measured by the BPP is shown to significantly differ from the floating potential both in polarity and profile shape. By combining the BPP potential and the floating potential, the electron temperature can be measured, which is compared with the Thomson scattering (TS) diagnostic. Excellent agreement between the two diagnostics is obtained when secondary electron emission is accounted for in the floating potential. From the BPP profile, an estimate of the radial electric field is extracted which is shown to be of the order ∼1 kV/m and increases with plasma current. Corrections to the BPP measurement, constrained by the TS comparison, introduce uncertainty into the ER measurements. The uncertainty is most significant in the electric field well inside the separatrix. The electric field is used to estimate toroidal and poloidal rotation velocities from E × B motion. This paper further demonstrates the ability of the ball pen probe to make valuable and important measurements in the boundary plasma of a tokamak.

Case controlled study of the hospital stay and return to full activity following laparoscopic and open colorectal surgery before and after the introduction of an enhanced recovery programme.

AIM: The short-term benefits of laparoscopic surgery are well established and in particular within an enhanced recovery programme. Early return to activity is to be expected but has not been quantified widely. The aim of this study was to measure the hospital stay and return to full activity following laparoscopic colorectal surgery and compare this with a matched group of patients undergoing open colorectal resections before and after the introduction of an enhanced recovery programme. METHOD: Retrospective analysis of all laparoscopic colorectal operations performed between January 2003 and June 2007 on an intention to treat basis compared with a matched group of patients undergoing elective open colorectal surgery at the same institution. RESULTS: The median hospital stay following 179 laparoscopic colorectal resections was 6 days whilst following 144 conventional open operations it was 8 days. Following the introduction of an enhanced recovery programme the hospital stay fell from 7 to 5 days and from 9 to 7 days for laparoscopic and open groups respectively. The median return to full activity from surgery for laparoscopic patients was 13 days in comparison to 56 days for patients undergoing open colorectal surgery. CONCLUSIONS: Following laparoscopic colorectal resection, patients can be expected to have a hospital stay of under a week and return to their usual activities as early as a week after discharge from hospital and < 2 weeks from surgery in comparison to patients undergoing open surgery who take 8 weeks or more to recover.

[The assessment of thyroid gland function in patients with non-insulin dependent diabetes mellitus (type II)]. / Ocena funkcji tarczycy u osób chorych na cukrzyce niezalezna od insuliny (typu II).

The aim of the study was to assess thyroid gland function in non-insulin dependent diabetes mellitus patients under different therapeutic regimens. There were examined 75 patients with type II diabetes mellitus, age range 33-80 years (average 65.24 +/- 14.32 years) including 46 women and 29 men. Group I was treated with insulin, group II--with diet, and group III--with sulfonylurea derivatives oral antidiabetic agents. Control group consisted of 91 healthy persons in appropriate age. The highest glucose levels were in insulin treated group--174.17 +/- 40.31 mg%, and were significantly higher from the values observed in oral antidiabetic agents treated group (169.89 +/- 41.34 mg%), and in diet treated group, where glucose levels were the lowest--134.57 +/- 25.06 mg%. In both groups--patients treated with insulin and with oral antidiabetic agents a positive correlation between fT4 and glycated hemoglobin levels were observed. Performed experiments and investigations suggest: 1. There are no differences in thyroid gland function in patients with non-insulin dependent diabetes mellitus. 2. Different therapies (diet, insulin therapy, oral antidiabetic agents) have no influence on thyroid gland function.

[Enzyme therapy in the treatment of lymphedema in the arm after breast carcinoma surgery]. / Enzymoterapie v lécbe lymfedému paze po operaci pro karcinom prsu.

The authors evaluate the contribution of proteolytic enzymes used in the treatment of the lymphatic oedema of the arm after mastectomy and radiotherapy for breast cancer. Proteolytic enzymes were successfully administered in monotherapy of lymphatic oedema as well as supportive therapy in other therapeutically ways.

[Comments on Wang's method of preparation of the recurrent laryngeal nerve in total thyroidectomy]. / Poznámky k Wangove metode preparace nervus laryngeus recurrens pri totálních tyroidektomiích.

The authors focus their attention on the problem of preparation of the recurrent laryngeal nerve in total thyroidectomy. Similarly as the majority of authors, the present authors use as the main guide during preparation of the recurrent nerve its relationship to the lower thyroid artery. As an alternative procedure they mention Wang's method which they tested in several tens of total thyroidectomies. In the submitted paper they discuss the advantages and disadvantages of this method.

[Spinocellular carcinoma as a rare complication in pilonidal cyst]. / Spinocelulární karcinom jako vzácná komplikace pilonidálního sinu.

The authors present two cases where on the basis of the pilonidal sinus spinocellular carcinoma developed. Both patients were successfully operated. The first one has been for three years, the second one for eight months without relapse. From the paper ensues that cancerization of the pilonidal sinus must be considered a very serious complication and must be prevented by early surgery.

[Use of the "Multitest-CMI" in the evaluation of cutaneous delayed hypersensitivity reaction to antigens in patients with chronic diseases of the liver]. / Zastosowanie "Multitestu-CMI" w ocenie skórnej odpowiedzi typu póznego na antygeny przypominajace u chorych z przewlekøymi chorobami watroby.

Delayed cutaneous hypersensitivity was assessed in 120 patients (among them 109 HBsAg positive), with chronic persistent hepatitis, chronic active hepatitis, and compensated as well as decompensated liver cirrhosis by simultaneous application of seven standardized antigens and negative control ("Multitest CMI"). In 21 patients, after 12-24 months the tests were repeated. The sum of indurations of all positive responses ("score") were calculated. Responsiveness measured as results below a normal values was related to the advancing of liver disease (from 13% in chronic persistent hepatitis up to 77% in compensated and 61% in decompensated liver cirrhosis). A comparative analysis (t-Student test) of the arithmetical means of the "scores" revealed statistically significant differences between results obtained in diagnostic groups. It was also dependent from the severity of liver disease. Patients with chronic persistent hepatitis (without specific treatment) and patients with chronic active hepatitis (treated using thymus extract, TFX - "Polfa") has showed an increased "score" values. In contrast to this group, all persons with liver cirrhosis without skin-responsiveness in the first and second tests (anergy) died at the period of 18 months. "Multitest CMI" can be of value in assessing of results of immunotherapy, as well as prognosis of the course of advanced liver disease.