Beam optical calculations for SPIRAL2

Ions of high charge states as required for both stable and radioactive beams in order to optimaly profit from the accelerating voltage provided can be produced by means of charge state breeders. However, the energy increase obtained is accompanied by an intensity decrease due to the low efficiency of the charge breeding process itself. With respect to the production of radioactive beams an enhancement of the breeding efficiency would be most desirable to avoid a high power primary beam as yet inevitable to counteract the loss in intensity. For this purpose the beam optics of an ion recirculation capable to separate the desired charge state and to reinject the remaining charge spectrum has been designed. The ions, potentially extracted from both sides of the charge breeder, are focused by means of electrostatic quadrupole doublets and bent by two 180° dipole magnets resulting in a racetrack-like shape. After one revolution the optics realises horizontally and vertically a point-to-point image independent from the charge state of the ions. The second order geometric aberrations as well as most of the chromatic aberrations vanish. The non-zero energy dependeant aberrations are compensated by the charge dependent aberrations leading to an effectively achromatic system up to the second order. The beam optivcal calculations have been carried out with the arbitrary order beam physics code COSY INFINITY and been validated with the beam enveloppe code TRANSPORT

Abraham Lincoln Memorial Park

This postcard features an Abraham Lincoln statue in Charleston, Illinois.https://scholarsjunction.msstate.edu/fvw-artifacts/5959/thumbnail.jp

Beam-based alignment of TTF RF-gun using V-Code

The beam dynamics simulation code V [1,2], based on the Ensemble Model [3], is being developed for on-line simulations. One practical application of the V-Code is the beam-based alignment (BBA) of accelerator (TESLA Test Facility) elements. Before we started with BBA thefirst beam position monitor (BPM1), located after the RFgun cavity, showed non-zero readings. Moreover the readings depended on RF-power, RF-phase and primary and secondary solenoid currents. This effect could be explained by misalignments of the gun and the solenoids. Such beam offsets must be compensated by means of steering coils but such a procedure can be one of the sources of increased emittances. Based on the V-Code solver a dedicated utility was developed for alignment studies. The laser beam mismatch at the cathode, as well as the primary and secondary solenoid displacements were considered as probable reasons for the misalignment of the beam. A new method for the correction of these misalignments combines a sequence of measurements, simulations and the elimination of the largest imperfections. This semi-automatic method applied to the TTF RF-gun yields a centering of the beam within the accuracy of the BPM1

Investigation of TTF injector alignment with the simulation Code V

The exact alignment of accelerator components is of crucial importance for the production of low emittance beams. Once a beam-line section is set up, a supplementary correction of misalignments implies the knowledge of its magnitude which is difficult to determine using conventional adjusting instruments. An excellent alternative to measure existing misalignments of accelerator components is to vary machine parameters and compare the behaviour of the beam with results obtained from a simulation. It is obvious that time consuming particle tracking programmes are notappropriate to reach this aim. Regarding computing time, the on-line simulation code V is advantageous compared to other beam dynamics programmes. The theoretical basis of V-Code, the “Ensemble Model”, consists of selfconsistent equations for the ensemble parameters that arederived from the Vlasov equation. The requirement to simulate misalignments such as offsets and tilts led to the development of the ALIGNMENT UTILITY which utilizes the solver of V-Code. The new utility enabled us to investigate the beam-line alignment of the TESLA Test Facility injector.This contribution presents the theoretical background and an illustrating example of the optimization process

REACCELERATION OF ION BEAMS FOR PARTICLE THERAPY

Abstract At the Heidelberg Ion-Beam Therapy Centre (HIT) more than 2000 cancer patients have been treated with ions using the raster-scanning method since 2009. The synchrotron provides pencil beams in therapy quality for more than 250 energy steps for each ion species allowing to vary the penetration depth and thus to irradiate the tumour slice-by-slice. So far, changing the beam energy necessitates a new synchrotron cycle, including all phases without beam extraction. As the number of ions that can be accelerated in the synchrotron usually exceeds the required number of ions for one energy slice, the duty cycle could be significantly reduced by reaccelerating or decelerating the remaining ions to the adjacent energy level. By alternating acceleration and extraction phases several slices could be irradiated with only short interruptions. This leads to a better duty cycle and a larger number of patients that can be treated in the same time. Therefore the behaviour of a reaccelerated but transversally blown up beam -due to the use of RF-knockout extraction -must be investigated in detail, beam losses have to be minimised. To estimate the potential benefit of such an operation mode, treatment time has been simulated and compared to the time achieved in the past. A reduction of more than 50 % is possible

Downregulation of duodenal SLC transporters and activation of proinflammatory signaling constitute the early response to high altitude in humans

Solute carrier (SLC) transporters mediate the uptake of biologically active compounds in the intestine. Reduced oxygenation (hypoxia) is an important factor influencing intestinal homeostasis. The aim of this study was to investigate the pathophysiological consequences of hypoxia on the expression and function of SLCs in human intestine. Hypoxia was induced in human intestinal epithelial cells (IECs) in vitro (0.2; 1% O2 or CoCl2). For human in vivo studies, duodenal biopsies and serum samples were obtained from individuals (n = 16) acutely exposed to 4,554 meters above sea levels. Expression of relevant targets was analyzed by quantitative PCR, Western blotting, or immunofluorescence. Serum levels of inflammatory mediators and nucleosides were determined by ELISA and LC/MS-MS, respectively. In the duodenum of volunteers exposed to high altitude we observed decreased mRNA levels of apical sodium-dependent bile acid transporter (ASBT), concentrative nucleoside transporters 1/2 (CNT1/2), organic anion transporting polypeptide 2B1 (OATP2B1), organic cation transporter 2 (OCTN2), peptide transporter 1 (PEPT1), serotonin transporter (SERT), and higher levels of IFN-γ, IL-6, and IL-17A. Serum levels of IL-10, IFN-γ, matrix metalloproteinase-2 (MMP-2), and serotonin were elevated, whereas the levels of uridine decreased upon exposure to hypoxia. Hypoxic IECs showed reduced levels of equilibrative nucleoside transporter 2 (ENT2), OCTN2, and SERT mRNAs in vitro, which was confirmed on the protein level and was accompanied by activation of ERK1/2, increase of hypoxia-inducible factor (HIF) proteins, and production of IL-8 mRNA. Costimulation with IFN-γ and IL-6 during hypoxia further decreased the expression of SERT, ENT2, and CNT2 in vitro. Reduced oxygen supply affects the expression pattern of duodenal SLCs that is accompanied by changes in serum levels of proinflammatory cytokines and biologically active compounds demonstrating that intestinal transport is affected during systemic exposure to hypoxia in humans

Trends in drinking habits among adolescents in the Baltic countries over the period of transition: HBSC survey results, 1993–2002

BACKGROUND: The Baltic countries – Estonia, Latvia, and Lithuania – are considered to be an example of regional homogeneity over the period of transition. The World Health Organization cross-national study on Health Behavior in School-aged Children (HBSC) allows a comparison and time trends analysis of behavioral patterns among adolescents in this region. The aim of this study was to estimate the prevalence and trends of alcohol consumption and drunkenness among adolescents of Estonia, Latvia, and Lithuania in 1993/94, 1997/98, and 2001/02. METHODS: Representative samples of 5286 boys and 6485 girls aged 15 from Estonia, Latvia, and Lithuania were surveyed in 1993/94, 1997/98, and 2001/02 school-year within the framework of HBSC study. The standardized survey methods were applied. The research focused on the following outcome variables: i) frequency of drinking beer, wine, and spirits; and ii) frequency of drunkenness. The same wording of questions on the consumption of alcohol was retained in each survey. RESULTS: Beer was the most frequently used alcoholic beverage across the Baltic countries among adolescents. The rate of weekly drinking of any alcoholic beverage increased considerably during the eight years of observation, especially among Estonian and Lithuanian students. In 2001/02, 25% of boys and 12.5% of girls have reported drinking alcohol at least weekly. The rate of regular alcohol drinking was two times higher in boys, while irregular drinking was more prevalent in girls. Two or more episodes of drunkenness in the lifespan were reported by 30% of boys and 15% of girls in 1993/94 and by 52% of boys and 36% of girls in 2001/02. The use of alcoholic beverages was related to the perceived family wealth: the students from the families perceived by them as wealthy were more likely to drink weekly as compared to the students from the families perceived by them as not wealthy. CONCLUSION: Over the period between 1993 and 2002 the prevalence of alcohol consumption among adolescents increased considerably across the Baltic countries. The efforts of dealing with this problem should employ a combination of measures, including the strategies relevant for the period of transition

Suicidal tendencies and attitude towards freedom to choose suicide among Lithuanian schoolchildren: results from three cross-sectional studies in 1994, 1998, and 2002

BACKGROUND: Suicidal behaviour is increasingly becoming a phenomenon associated with young people and an important public health issue in Lithuania. However, there are very few studies evaluating impact of young peoples' attitudes towards suicide to their suicidal behaviour. A better understanding of the relations among the variables associated with suicidal ideation and threats in the normal population of adolescents may eventually result in a better understanding of the more serious forms of adolescent suicidal behaviour. The aim of the present study was to evaluate prevalence of suicidal tendencies among Lithuanian schoolchildren and to estimate its association with an attitude towards suicide in 1994 – 2002. METHODS: Three country representative samples of schoolchildren, aged 11, 13 and 15, were surveyed in 1994 (n = 5428), 1998 (n = 4513), and 2002 (n = 5645) anonymously in conformity with the methodology of the World Health Organization Cross – National study on Health Behaviour in School-aged Children (HBSC). RESULTS: About one third of respondents reported about suicidal ideation, plans or attempts to commit suicide. In the study period of eight years, the percentage of adolescents who reported sometime suicidal ideation decreased but the percentage of adolescents who declared serious suicidal behaviour remained on the same high level (8.1%, 9.8% and 8.4% correspondingly in 1994, 1998 and 2002). Moreover, the number of suicidal attempts changed from 1.0% in 1994 to 1.8% in the year 1998 and to 1,7% in the year 2002. The schoolchildren's attitude towards suicide became more agreeable: 36.6%, 41.9% and 62.5% of respondents, correspondingly in 1994, 1998 and 2002, answered that they agree with a person's freedom to make a choice between life and suicide. A multiple logistic regression analysis with low level of suicidality and high level of suicidality versus non suicidal behaviour as dependent variables for gender, age, year of the survey and attitude towards freedom to choose suicide as independent variables approved a significant association between studied covariates over the entire study period. CONCLUSION: Suicidal tendencies are quite frequent among Lithuanian adolescents. An increasing number of schoolchildren are expressing an agreeable attitude towards suicide. The approving attitude towards suicide among adolescents correlates with suicidal ideation and behaviour

A Review of Pharmacologic Treatment for Compulsive Buying Disorder

At present, no treatment recommendations can be made for compulsive buying disorder. Recent studies have found evidence for the efficacy of psychotherapeutic options, but less is known regarding the best pharmacologic treatment. The purpose of this review is to present and analyze the available published evidence on the pharmacological treatment of compulsive buying disorder. To achieve this, we conducted a review of studies focusing on the pharmacological treatment of compulsive buying by searching the PubMed/MEDLINE database. Selection criteria were applied, and 21 studies were identified. Pharmacological classes reported included antidepressants, mood stabilizers, opioid antagonists, second-generation antipsychotics, and N-methyl-D-aspartate receptor antagonists. We found only placebo-controlled trials for fluvoxamine; none showed effectiveness against placebo. Three open-label trials reported clinical improvement with citalopram; one was followed by a double-blind discontinuation. Escitalopram was effective in an open-label trial but did not show efficacy in the double-blind phase. Memantine was identified as effective in a pilot open-label study. Fluoxetine, bupropion, nortriptyline, clomipramine, topiramate and naltrexone were only reported to be effective in clinical cases. According to the available literature, there is no evidence to propose a specific pharmacologic agent for compulsive buying disorder. Future research is required for a better understanding of both pathogenesis and treatment of this disorder.info:eu-repo/semantics/publishedVersio