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1.
MMW Fortschr Med ; 161(Suppl 6): 2, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31587171
2.
Rev Sci Instrum ; 85(2): 02A922, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593501

RESUMO

A new superconducting Electron Cyclotron Resonance Ion Source (ECRIS) is under development at LBNL to harness the winding techniques of a closed-loop sextupole coil for the next generation ECRIS and to enhance the capability of the 88-in. cyclotron facility. The proposed ECRIS will use a superconducting closed-loop sextupole coil to produce the radial field and a substantial portion of the axial field. The field strengths of the injection, central and extraction regions are adjusted by a three solenoids outside the closed-loop sextupole coil. In addition to maintaining the typical ECRIS magnetic field configuration, this new source will also be able to produce a dustpan-like minimum-B field to explore possible ECRIS performance enhancement. The dustpan-like minimum-B field configuration has about the same strengths for the maximum axial field at the injection region and the maximum radial pole fields at the plasma chamber walls but it can be substantially lower at the extraction region. The dustpan-like minimum-B will have a field maximum Bmax ≥ 2.6 T for operations up to 18 GHz with a ratio of Bmax/Bres ≥ 4 and higher ratios for lower frequencies. The field maxima of this new source can reach over 3 T both at the injection and the plasma chamber walls which could also support operation at 28 GHz. The source will be built of cryogen-free with the magnets directly cooled by cryo-coolers to simplify the cryostat structure. The source design features will be presented and discussed.

3.
Rev Sci Instrum ; 85(2): 02A932, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593511

RESUMO

A number of superconducting electron cyclotron resonance (ECR) ion sources use gyrotrons at either 24 or 28 GHz for ECR heating. In these systems, the microwave power is launched into the plasma using the TE01 circular waveguide mode. This is fundamentally different and may be less efficient than the typical rectangular, linearly polarized TE10 mode used for launching waves at lower frequencies. To improve the 28 GHz microwave coupling in VENUS, a TE01-HE11 mode conversion system has been built to test launching HE11 microwave power into the plasma chamber. The HE11 mode is a quasi-Gaussian, linearly polarized mode, which should couple strongly to the plasma electrons. The mode conversion is done in two steps. First, a 0.66 m long "snake" converts the TE01 mode to the TE11 mode. Second, a corrugated circular waveguide excites the HE11 mode, which is launched directly into the plasma chamber. The design concept draws on the development of similar devices used in tokamaks and stellerators. The first tests of the new coupling system are described below.

4.
Rev Sci Instrum ; 85(2): 02A961, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593540

RESUMO

Recently the Versatile ECR for NUclear Science (VENUS) ion source was engaged in a 60-day long campaign to deliver high intensity (48)Ca(11+) beam to the 88-Inch Cyclotron. As the first long term use of VENUS for multi-week heavy-element research, new methods were developed to maximize oven to target efficiency. First, the tuning parameters of VENUS for injection into the cyclotron proved to be very different than those used to tune VENUS for maximum beam output of the desired charge state immediately following its bending magnet. Second, helium with no oxygen support gas was used to maximize the efficiency. The performance of VENUS and its low temperature oven used to produce the stable requested 75 eµA of (48)Ca(11+) beam current was impressive. The consumption of (48)Ca in VENUS using the low temperature oven was checked roughly weekly, and was found to be on average 0.27 mg/h with an ionization efficiency into the 11+ charge state of 5.0%. No degradation in performance was noted over time. In addition, with the successful operation of VENUS the 88-Inch cyclotron was able to extract a record 2 pµA of (48)Ca(11+), with a VENUS output beam current of 219 eµA. The paper describes the characteristics of the VENUS tune used for maximum transport efficiency into the cyclotron as well as ongoing efforts to improve the transport efficiency from VENUS into the cyclotron. In addition, we briefly present details regarding the recent successful repair of the cryostat vacuum system.


Assuntos
Isótopos de Cálcio/química , Ciclotrons/instrumentação , Temperatura Baixa
5.
MMW Fortschr Med ; 155 Suppl 2: 63-71, 2013 Jul 25.
Artigo em Alemão | MEDLINE | ID: mdl-24930324

RESUMO

BACKGROUND: A patient-orientated therapy management for patients with severe chronic pain includes effective analgesia, improvement of health related quality of life and improvement of functionality. PATIENTS AND METHOD: In this prospective, non-interventional trial in 630 patients with severe chronic pain mostly due to chronic low back pain or gonarthrosis, treatment with tapentadol retard was evaluated with respect to its effects on analgesia, functionality and quality of life. Collected data included pain intensity, painDETECT,SF-12, FFbH-R and FFbH-OA. RESULTS: Mean pain intensity decreased significantly (NRS-3: -3.2 points, p < or = 0.001) and in 47.9% of the patients the mean pain intensity was reduced by at least 50%. Health-related quality of life and functionality improved significantly. Tolerability was good. The known tolerability profile of tapentadol retard could be confirmed. CONCLUSION: In this study in real-life-setting tapentadol was effective in terms of analgesic effect but also in terms of improvementof health-related quality of life and functionality, leading to a benefit for the patient in daily life.


Assuntos
Dor nas Costas/tratamento farmacológico , Fenóis/uso terapêutico , Atividades Cotidianas/classificação , Atividades Cotidianas/psicologia , Idoso , Preparações de Ação Retardada , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Fenóis/efeitos adversos , Estudos Prospectivos , Qualidade de Vida , Tapentadol
6.
Rev Sci Instrum ; 83(2): 02A311, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380158

RESUMO

The 28 GHz Ion Source VENUS (versatile ECR for nuclear science) is back in operation after the superconducting sextupole leads were repaired and a fourth cryocooler was added. VENUS serves as an R&D device to explore the limits of electron cyclotron resonance source performance at 28 GHz with its 10 kW gryotron and optimum magnetic fields and as an ion source to increase the capabilities of the 88-Inch Cyclotron both for nuclear physics research and applications. The development and testing of ovens and sputtering techniques cover a wide range of applications. Recent experiments on bismuth demonstrated stable operation at 300 eµA of Bi(31+), which is in the intensity range of interest for high performance heavy-ion drivers such as FRIB (Facility for Rare Isotope Beams). In addition, the space radiation effects testing program at the cyclotron relies on the production of a cocktail beam with many species produced simultaneously in the ion source and this can be done with a combination of gases, sputter probes, and an oven. These capabilities are being developed with VENUS by adding a low temperature oven, sputter probes, as well as studying the RF coupling into the source.

7.
Rev Sci Instrum ; 83(2): 02B706, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380311

RESUMO

In this paper, an ongoing effort to provide a simulation and design tool for electron cyclotron resonance ion source extraction and low energy beam transport is described and benchmarked against experimental results. Utilizing the particle-in-cell code WARP, a set of scripts has been developed: A semiempirical method of generating initial conditions, a 2D-3D hybrid method of plasma extraction and a simple beam transport deck. Measured emittances and beam profiles of uranium and helium beams are shown and the influence of the sextupole part of the plasma confinement field is investigated. The results are compared to simulations carried out using the methods described above. The results show that the simulation model (with some additional refinements) represents highly charged, well-confined ions well, but that the model is less applicable for less confined, singly charged ions.

8.
Rev Sci Instrum ; 81(2): 02B710, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192450

RESUMO

This paper describes the recent development and commissioning of a pepper-pot emittance meter at the Lawrence Berkeley National Laboratory (LBNL). It is based on a potassium bromide (KBr) scintillator screen in combination with a charged coupled device camera. Pepper-pot scanners record the full four-dimensional transverse phase space emittances which are particularly interesting for electron cyclotron resonance ion sources. The strengths and limitations of evaluating emittances using optical pepper-pot scanners are described and systematic errors induced by the optical data acquisition system will be presented. Light yield tests of KBr exposed to different ion species and first emittance measurement data using ion beams extracted from the 6.4 GHz LBNL electron cyclotron resonance ion source are presented and discussed.

9.
Schmerz ; 22(5): 594-603, 2008 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-18604567

RESUMO

Analgesic therapy is not without risk. However, the risk of most analgesic interventions is minor compared to the risk of the inadequate treatment of pain and insufficient treatment may lead to chronic pain.A correct diagnosis should be the basis of any specific treatment of pain disorders. Only a diagnosis which implicates a multi-disciplinary assessment and which considers both the pathoanatomical, functional and biopsychosocial dysfunctions can lead to an adequate therapeutic intervention. Furthermore, therapeutic planning should include the personal needs of the patient and should have realistic aims.Pharmacological treatment is guided by the WHO pain ladder. The risks of the relevant substance groups must be considered. NSAIDs (non-steroidal anti-inflammatory drugs) which are included in all steps of the WHO pain ladder carry specific risks for the gastrointestinal, cardiovascular and renal systems and are contraindicated in many patients in need of analgesic therapy, e.g. in many elderly patients. Opioids which are recommended at steps 2 and 3 of the WHO pain ladder have less organ toxicity but they are still used reluctantly. Coanalgetics, especially antidepressants bear specific risks and the discussion on suicide rates under antidepressant medication is ongoing.Invasive methods such as the intrathecal application of analgesics are valuable procedures if the indication is correct and the treating physician has sufficient experience. Pain therapy is essential and the risks of the procedures are manageable. Considering the current knowledge on the mechanisms of pain sensitisation, the lack of adequate pain control can lead to chronic pain with severe consequences for the patient.


Assuntos
Analgésicos/efeitos adversos , Dor/tratamento farmacológico , Analgesia Epidural/efeitos adversos , Analgésicos/uso terapêutico , Antidepressivos/efeitos adversos , Antidepressivos/uso terapêutico , Doença Crônica , Terapia Combinada , Interações Medicamentosas , Quimioterapia Combinada , Humanos , Bombas de Infusão , Dor/psicologia , Equipe de Assistência ao Paciente , Medição de Risco
10.
J Am Chem Soc ; 123(8): 1713-22, 2001 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-11456772

RESUMO

Two of the three conformational polymorphs of dimethyl-3,6-dichloro-2,5-dihydroxyterephthalate are studied by solid-state NMR techniques. The structural differences between the polymorphs have previously been studied by X-ray. In these two polymorphs named white and yellow due to their color, the major structural difference is the torsional angle between the ester group and the aromatic ring. The yellow form has a dihedral angle of 4 degrees between the plane of the aromatic ring and the plane of the ester group, while the white form has two different molecules per unit cell with dihedral angles of 70 degrees and 85 degrees. This change greatly affects the conjugation in the pi-electronic system. In addition, there are differences in the hydrogen-bonding patterns, with the white form having intermolecular hydrogen bonds and the yellow form having intramolecular hydrogen bonds. In this work, the carbon isotropic chemical shift values and the chlorine electric field gradient (EFG) tensor information are extracted from the (13)C MAS spectra, and the principal values of the chemical shift tensors of the carbons are obtained from 2D FIREMAT experiments. Quantum chemical calculations of the chemical shift tensor data as well as the EFG tensor are performed at the HF and DFT levels of theory on individual molecules and on stacks of three molecules to account for the important intermolecular interactions in the white form. The differences between the spectral data on the two polymorphs are discussed in terms of the known electronic and structural differences.


Assuntos
Ácidos Ftálicos/química , Isótopos de Carbono , Imageamento por Ressonância Magnética , Conformação Molecular
11.
Unfallchirurgie ; 14(4): 184-90, 1988 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-3176187

RESUMO

We evaluated the results of treatment in six patients with unreduced chronic anterior dislocations of the shoulder. In three patients the dislocations had not been recognized by the initial treating physician. In the remaining three patients the dislocations initially had been diagnosed but reduction had failed and the dislocations had remained unreduced. In one of the six shoulders the dislocation was left unreduced. The dislocation existed for 3.5 years and there was absence of disabling functional impairment, pain or neurovascular disturbance. In five of six shoulders the function was severely impaired. One of five shoulders with an anterior dislocation of three weeks duration could be reduced by closed manipulation. Four shoulders underwent open reduction. In all patients the humeral head could be preserved. Associated osseous lesions of the glenoid or the humeral head (Hill-Sachs lesions, fractures) were treated by rotation osteotomies according to Weber and the Eden-Lange-Hybinette procedure. Preoperatively all shoulders were graded as poor. Postoperatively the results in one was graded as excellent, in three as good and in one (algodystrophy of the left arm) as fair.


Assuntos
Osteotomia/métodos , Luxação do Ombro , Adolescente , Adulto , Idoso , Doença Crônica , Feminino , Fixação de Fratura/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Luxação do Ombro/diagnóstico por imagem , Luxação do Ombro/cirurgia , Fraturas do Ombro/diagnóstico por imagem , Fraturas do Ombro/cirurgia
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