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Regenerative Gaskreisprozesse, wie z. B. der Stirlingmotor, sind geschlossene Maschinen, in denen ein Arbeitsgas durch Zylinder-Kolben Anordnungen Energie von einer Warmequelle zu einem kalteren Reservoir ubertragt. Die Kanale der Warmeubertrager werden hierbei oszillierend durchstromt und weisen damit, im Vergleich zu stationaren Stromungen, hinsichtlich des Warmeubergangs und der Stromungsdruckverluste ein grundsatzlich abweichendes Verhalten auf. In dem vorliegenden Beitrag wurden die Geschwindigkeit und der Druckverlust von oszillierenden Stromungen in Kanalen theoretisch und numerisch untersucht. Dabei sind sowohl kreisformige als auch rechteckige Kanale mit Reynolds-Zahlen im Bereich laminarer und turbulenter Stromungen betrachtet worden. Die numerische Simulation wurde in ANSYS-CFX realisiert und nutzt bewegte Gitter um die Volumenanderung der Kolben abzubilden. Die Ubereinstimmung zwischen analytischer Losung und numerischer Simulation fur den Fall niedriger Reynolds-Zahlen ist sehr gut. Wie erwartet zeigten sich deutliche Unterschiede zwischen der numerischen Simulation und der analytischen Losung bei hoheren Reynolds-Zahlen (turbulente Stromung), die aufgrund fehlender analytischer Gleichungen allerdings nicht validiert werden konnten. Durch Analyse und Auswertung der Einflussgrosen wurden dimensionslose Kennzahlen erhalten sowie ein halbempirischer Ansatz unter Verwendung komplexer Zahlen entwickelt, welcher die Zeitabhangigkeit des Druckverlustes approximiert. Die darin auftretenden Modellkoeffizienten konnen unter Zuhilfenahme der Ergebnisse der numerischen Simulationen bestimmt werden und erlauben eine Abschatzung des Druckverlustes ohne Verwendung zeitaufwandiger CFD-Berechnungen.

The formation of high-mass stars is one of the major topics of astrophysical research, in particular the process of accretion from large-scale clouds down to small-scale cores. We have selected the nearby, filamentary, high-mass star forming complex NGC 6334 to study the gas velocity at different scales and probe the infall rates onto the protostellar cores embedded in the NGC 6334-I and I(N) clusters. This study makes use of single-dish and interferometric submillimeter observations, complemented with 3D numerical non-LTE radiative transfer modeling. We measure a mass accretion rate of 10−5 M ⊙ yr−1 throughout the filament increasing up to 10−3 M ⊙ yr−1 towards the densest regions where high-mass stars are forming. At smaller scales, our 3D model is consistent with accretion rates of 10−3 M ⊙ yr−1 towards the clusters, and 10−4 M ⊙ yr−1 onto the protostars.

We present results from radiative transfer modeling of the continuum emission towards Sagittarius B2 (hereafter Sgr B2). We have developed a radiative transfer framework – Pandora – that employs RADMC-3D (Dullemond 2012) for a self-consistent determination of the dust temperature. With this pipeline, we have set-up a single model that consistently reproduces the thermal dust and free-free continuum emission of Sgr B2 spanning four orders of magnitude in spatial scales (0.02–45 pc) and two orders of magnitude in frequency (20–4000 GHz).

The design and evaluation of a velocity map imaging spectrometer specifically optimised for experiments at the FERMI free electron laser source are described. Optimisation of the set-up for the detection of high energy electrons (experimentally calibrated up to 45 eV), reduction of scattered light and characterisation of the pulsed gas source are outlined. The instrument has been tested using synchrotron light at the GasPhase beamline at Elettra, the Italian synchrotron source, and the results are presented. © 2011 Elsevier B.V. All rights reserved.

Objective: Transjugular intrahepatic portosystemic shunt (TIPS) efficiently treats complications of portal hypertension. Liver and spleen stiffness might predict clinically significant portal hypertension. This prospective study investigated liver stiffness in patients receiving TIPS regardless of indication. Design: Of 83 included patients, 16 underwent TE immediately before and 30 minutes after TIPS (acute group), while 67 patients received shear wave elastography (SWE) of liver and spleen one day before and seven days after TIPS (chronic group) and were followed further. In blood samples obtained before TIPS from cubital, portal and hepatic veins, interleukins (IL) (IL1b, IL6, IL8, IL10, IL18) and interferon gamma were analyzed. Results: In 27 patients (five acute, 22 chronic), it resulted in an increase in liver stiffness of more than 10%. In 56 patients, liver stiffness decreased or remained unchanged (

Robotic liver resection can overcome some of the limitations of laparoscopic liver surgery; therefore, it is a promising tool to increase the proportion of minimally invasive liver resections. The present article gives an overview of the current literature. Furthermore, the results of a nationwide survey on robotic liver surgery among hospitals in Germany with a DaVinci system used in general visceral surgery and the perioperative results of two German robotic centers are presented.

One-phonon states of vibrational nuclei with mixed proton–neutron symmetry have been observed throughout the nuclear chart besides the mass A≈200 region. Very recently, it has been proposed that the 22 + state of 212Po is of isovector nature. This nucleus has two valence protons and two valence neutrons outside the doubly-magic 208Pb nucleus. The stable isotope 204Hg, featuring two valence-proton and valence-neutron holes, with respect to 208Pb, is the particle-hole mirror of 212Po. In order to compare the properties of low-lying isovector excitations in these particle-hole mirror nuclei, we have studied 204Hg by using the projectile Coulomb-excitation technique. The measured absolute B(M1;22 +→21 +) strength of 0.20(2)μN 2 indicates that the 22 + level of 204Hg is at least the main fragment of the 21,ms + state. For the first time in this mass region, both lowest-lying, one-quadrupole phonon excitations are established together with the complete set of their decay strengths. This allows for a microscopic description of their structures, achieved in the framework of the Quasi-particle Phonon Model.

General expressions for the matrix elements of the tight-binding operator are presented using the Racah-Wigner algebra, where the wave functions are expressed as coupled multiplet wave functions within a given angular momentum coupling scheme. The knowledge of all possible Slater determinants is not necessary and the matrix elements can be written as compact expressions computable with arbitrary accuracy.

We have used an unbiased, spectral line-survey that covers the frequency range from 211 to 275 GHz and was obtained with ALMA (angular resolution of 0.4 arcsec) to study the small-scale structure of the dense gas in Sagittarius B2 (north). Eight filaments are found converging to the central hub and extending for about 0.1 pc. The spatial structure, together with the presence of the massive central region, suggest that these filaments may be associated with accretion processes. In order to derive the kinematic properties of the gas in a chemically line-rich source like Sgr B2(N), we have developed a new tool that stacks all the detected transition lines of any molecular species. This permits to increase the signal-to-noise ratio of our observations and average out line blending effects, which are a common problem in line-rich regions. We derive velocity gradients along the filaments of about 20-100 km s$^{-1}$ pc$^{-1}$, which are 10-100 times larger than those typically found on larger scales (1 pc) in other star-forming regions. The mass accretion rates of individual filaments are about 0.05 M$_\odot$ yr$^{-1}$, which result in a total accretion rate of 0.16 M$_\odot$ yr$^{-1}$. Some filaments harbor dense cores that are likely forming stars and stellar clusters. The stellar content of these dense cores is on the order of 50% of the total mass. We conclude that the cores may merge in the center when already forming stellar clusters but still containing a significant amount of gas, resulting in a "damp" merger. The high density and mass of the central region, combined with the presence of converging filaments with high mass, high accretion rates and embedded dense cores already forming stars, suggest that Sgr B2(N) may have the potential to evolve into a super stellar cluster., Accepted for publication in Astronomy & Astrophysics. 10 pages with 8 figures and 2 tables, plus Appendices with extra figures and tables. (Abstract modified)

Purpose To determine the retest variability of mesopic and two-color dark-adapted (DA) fundus-controlled perimetry (FCP), to evaluate the predictive value of patient reliability indices, and to analyze the extent of impairment of rod- and cone function in neovascular age-related macular degeneration (nAMD). Methods A total of 50 eyes of 50 patients with nAMD (mean age, 76.1 years) and 70 eyes of 70 age-similar normal subjects underwent multimodal imaging as well as mesopic and DA two-color perimetry using the S-MAIA device. A subset of patients (n = 28) underwent duplicate testing for retest reliability assessment. Mixed models were used for analysis of the hierarchical data. Results In eyes with nAMD, the coefficient of repeatability was (mean ± standard deviation [SD]) 5.99 ± 1.55 dB for mesopic, 6.14 ± 2.19 dB for DA cyan, and 6.06 ± 1.09 dB for DA red testing. “Patient reliability indices” explained 55%, 54.2%, and 64.2% of the variance in retest variability. The mean sensitivity loss was greater for DA cyan compared to DA red testing (cyan-red differences [mean ± SD] −2.63 ± 3.87 dB, P < 0.001). Conclusions The relatively greater degree of DA cyan versus DA red sensitivity loss indicates preferential rod vulnerability in nAMD, and qualifies rod function-based outcomes measures as potential sensitive and early markers of treatment response in nAMD. Translational Relevance The S-MAIA allows reliable testing of mesopic, DA cyan, and DA red sensitivity in patients with nAMD. Patient reliability indices may serve as eligibility criteria for clinical trials to identify patients with adequate retest reliability.

Purpose To investigate the interreader and intermodality agreement for grading of retinal pigment epithelium (RPE) atrophy lesion size in ABCA4-related retinopathy using green (GAF) and blue fundus autofluorescence (BAF) imaging. Methods In this cross-sectional case series, 97 eyes of 49 patients with RPE atrophy secondary to ABCA4-related retinopathy underwent GAF- (518 nm excitation light) and BAF- (488 nm excitation light) imaging using confocal scanning laser ophthalmoscopy (Spectralis HRA, Heidelberg Engineering, Heidelberg, Germany). Lesions with definitely decreased autofluorescence (DDAF) and questionably decreased autofluorescence (QDAF) in GAF and BAF imaging were analyzed separately by five independent readers using semiautomated software (RegionFinder, Heidelberg Engineering). Intermodality and interreader agreements were assessed for the square-root lesion size, lesion perimeter, and circularity. Results GAF- and BAF-based measurements of DDAF and QDAF showed high intermodality and interreader agreement concerning square-root lesion size, as well as shape descriptive parameters (perimeter and circularity). Interreader agreement of square-root lesion size was slightly, hence not significantly higher for GAF-based grading ([95% coefficients of repeatability, intraclass correlation coefficient] DDAF: 0.215 mm, 0.997; QDAF: 0.712 mm, 0.981) compared to BAF-based grading (DDAF: 0.232 mm, 0.997; QDAF: 0.764 mm, 0.978). However, DDAF-measurements revealed distinctly more reproducible results than QDAF-measurements. Foveal sparing did not interfere with intermodality agreement. Conclusions Both GAF- and BAF-based quantification of RPE atrophy showed very reliable results with possible superiority of GAF in the context of less energetic excitation light. Translational Relevance The high interreader agreement qualifies the use of DDAF progression in GAF and BAF imaging as potential morphologic outcome measure for interventional clinical trials and disease monitoring.

The NAVIgation DOsimetry System (NAVIDOS) comprises a complete readout system for a radiation detec- tor, an air pressure sensor and a GPS receiver. The detector system DOSTEL uses silicon detectors which make NAVI- DOS light weighted and compact in size. Therefore, NAVI- DOS is well suited to be installed on board aircraft. The cal- ibration of NAVIDOS in terms of ambient dose equivalent is done by an in-field comparison with the PTB reference in- strument DOS. We also show that the dependence of these results on the vertical cut-off rigidity can be explained by the low response of the silicon detectors for neutrons. Therefore, in-flight measurements have been performed together with the PTB reference instrument DOS. The dose rates, cal- culated using the PTB code FDOScalc, were verified with these DOS measurements. The calibration of NAVIDOS was done with FDOScalc and results in calibration factors between 3.4 in the polar and 2.4 in the equator region.

Almost 200 different species have been detected in the interstellar medium (ISM) during the last decades, revealing not only simple species but complex molecules with more than 6 atoms. Other exotic compounds, like the weakly-bound dimer (H2)2, have also been detected in astronomical sources like Jupiter. We aim at detecting for the first time the CO-H2 van der Waals complex in the ISM, which if detected can be a sensitive indicator for low temperatures. We use the IRAM30m telescope, located in Pico Veleta (Spain), to search for the CO-H2 complex in a cold, dense core in TMC-1C (with a temperature of 10 K). All the brightest CO-H2 transitions in the 3 mm (80-110 GHz) band have been observed with a spectral resolution of 0.5-0.7 km/s, reaching a rms noise level of 2 mK. The simultaneous observation of a broad frequency band, 16 GHz, has allowed us to conduct a serendipitous spectral line survey. No lines belonging to the CO-H2 complex have been detected. We have set up a new, more stringent upper limit for its abundance to be [CO-H2]/[CO] = 5x10^{-6}, while we expect the abundance of the complex to be in the range 10^{-8}-10^{-3}. The spectral line survey has allowed us to detect 75 lines associated with 41 different species (including isotopologues). We detect a number of complex organic species, e.g. methyl cyanide (CH3CN), methanol (CH3OH), propyne (CH3CCH) and ketene (CH2CO), associated with cold gas (excitation temperatures about 7 K), confirming the presence of these complex species not only in warm objects but also in cold regimes., 9 pages, 3 figures, 2 tables. Accepted for publication in Astronomy & Astrophysics

We model the dust and free-free continuum emission in the high-mass star-forming region Sagittarius B2 in order to reconstruct the three-dimensional density and dust temperature distribution, as a crucial input to follow-up studies of the gas velocity field and molecular abundances. We employ the three-dimensional radiative transfer program RADMC-3D to calculate the dust temperature self-consistently, provided a given initial density distribution. This density distribution of the entire cloud complex is then recursively reconstructed based on available continuum maps, including both single-dish and high-resolution interferometric maps covering a wide frequency range (40 GHz - 4 THz). The model covers spatial scales from 45 pc down to 100 au, i.e. a spatial dynamic range of 10^5. We find that the density distribution of Sagittarius B2 can be reasonably well fitted by applying a superposition of spherical cores with Plummer-like density profiles. In order to reproduce the spectral energy distribution, we position Sgr B2(N) along the line of sight behind the plane containing Sgr B2(M). We find that the entire cloud complex comprises a total gas mass of 8.0 x 10^6 Msun within a diameter of 45 pc, corresponding to an averaged gas density of 170 Msun/pc^3. We estimate stellar masses of 2400 Msun and 20700 Msun and luminosities of 1.8 x 10^6 Lsun and 1.2 x 10^7 Lsun for Sgr B2(N) and Sgr B2(M), respectively. We report H_2 column densities of 2.9 x 10^24 cm^-2 for Sgr B2(N) and 2.5 x 10^24 cm^-2 for Sgr B2(M) in a 40" beam. For Sgr B2(S), we derive a stellar mass of 1100 Msun, a luminosity of 6.6 x 10^5 Lsun and a H_2 column density of 2.2 x 10^24 cm^-2 in a 40" beam. We calculate a star formation efficiency of 5% for Sgr B2(N) and 50% for Sgr B2(M), indicating that most of the gas content in Sgr B2(M) has already been converted to stars or dispersed., Comment: Accepted for publication in A&A. 30 pages, 24 figures, 6 tables

Recently, the UK guidelines on variceal bleeding1 and other reports have introduced the role of elastography for the diagnosis of oesophageal varices (OVs).2 ,3 Development of OVs is likely when the hepatic venous pressure gradient is higher than 10 mm Hg, which defines clinically significant portal hypertension (CSPH). Baveno VI implemented transient elastography (TE) as a tool to rule in CSPH in viral aetiologies and to rule out varices (need of screening endoscopy for varices).4 Furthermore, CSPH has a strong prognostic value in patients with cirrhosis. Recent studies introduced Shear-wave elastography of the liver (L-SWE) as a promising tool to diagnose portal hypertension. These studies find good diagnostic accuracy of L-SWE with specificity and sensitivity ranging around 80% and superior to TE. However, in more than 30% of the patients CSPH could not be ruled in or ruled out, since their SWE values were between the cut-offs. This prospective multicentre study investigated the …

International audience; To investigate the systematics of mixed-symmetry states in N=52 isotones, a relativistic Coulomb excitation experiment was performed during the PreSPEC campaign at the GSI Helmholtzzentrum für Schwerionenforschung to determine E2 transition strengths to 2+ states of the radioactive nucleus $^{88}$Kr. Absolute transition rates could be measured towards the first and third 2+ states. For the latter a mixed-symmetry character is suggested on the basis of the indication for a strong M1 transition to the fully symmetric 21+ state, extending the knowledge of the N=52 isotones below Z=40. A comparison with the proton-neutron interacting boson model and shell-model predictions is made and supports the assignment.

We model the emission of methyl cyanide (CH3CN) lines towards the massive hot molecular core SgrB2(M). We aim at reconstructing the CH3CN abundance field and investigating the gas temperature distribution as well as the velocity field. SgrB2(M) was observed with the ALMA in a spectral line survey from 211 to 275 GHz. This frequency range includes several transitions of CH3CN (including isotopologues and vibrationally excited states). We employ the three-dimensional radiative transfer toolbox Pandora in order to retrieve the velocity and abundance field by modeling different CH3CN lines. For this purpose, we base our model on the results of a previous study that determined the physical structure of SgrB2(M), i.e.\ the distribution of dust dense cores, ionized regions and heating sources. The morphology of the CH3CN emission can be reproduced by a molecular density field that consists of a superposition of cores with modified Plummer-like density profiles. The averaged relative abundance of CH3CN with respect to H2 ranges from 4x10^{-11} to 2x10^{-8} in the northern part of SgrB2(M) and from 2x10^{-10} to 5x10^{-7} in the southern part. In general, we find that the relative abundance of CH3CN is lower at the center of the very dense and hot cores, causing the general morphology of the CH3CN emission to be shifted with respect to the dust continuum emission. The dust temperature calculated by the radiative transfer simulation based on the available luminosity reaches values up to 900 K. However, in some regions vibrationally excited transitions of CH3CN are underestimated by the model, indicating that the predicted gas temperature, which is assumed to be equal to the dust temperature, is partly underestimated. The determination of the velocity component along the line of sight reveals that a velocity gradient from the north to the south exists in SgrB2(M)., Accepted for publication in Astronomy & Astrophysics. 18 pages with 18 figures and 1 table, plus Appendices with extra figures and tables

BACKGROUND: The aim of this study was to evaluate the effects of outpatient medical rehabilitation (OMR) mainly composed of exercise therapy and sports for patients with asbestosis. Following the Hamburg model, the OMR focuses on keeping up lasting effects. METHOD: In the frame of a pre-experimental study, 113 male asbestosis patients aged 66.1±5.8 years participated 6 hrs. a day five times a week over a period of three weeks in phase 1 of the OMR consisting of evidence-based contents of the pulmonary rehabilitation. Directly after that further therapeutic applications with the main focus on exercise therapy and sports were applied for 3 hrs. once a week over a period of twelve weeks (phase 2). After phase 2 the rehabilitation centre led the patients into sports groups near their places of residence (phase 3). The effects of the OMR were evaluated at the beginning (T1), at the end of phase 1 (T2) and phase 2 (T3) as well as 6 (T4) and 18 months (T5) after T3 by means of a suitable assessment. RESULTS: Compared to T1 physical fitness (6-minute Walk Test, Hand-Force Test) as well as health-related quality of life (SF-36), dyspnea (BDI/TDI) and oxygen partial pressure (pO2) were significantly improved in T2. These positive effects could be confirmed in T3. 89 patients (79%) were doing health-related sports regularly 6 and 18 months after T3 and could preserve their health outcome in T4 and T5, while the effects of rehabilitation of the 24 patients breaking off any sporting activities wore off again down to and even below the starting condition at T1. CONCLUSIONS: In spite of a restrictive pulmonary disease, specific exercise therapy and sports are able to mobilize physical reserves of performance and induce an increasing quality of life as well as a higher resilience in activities of daily living. These positive effects could be stabilized persistently by a regular training once a week. Thus, the results emphasize the necessity to include strategies of aftercare in the concept of rehabilitation.

Background The aim of this study was to evaluate the effects of an outpatient medical rehabilitation (OMR) mainly composed of exercise therapy and sports for patients with asbestosis. Following the model of Hamburg the OMR focuses on keeping up lasting effects. Methods In the frame of a pre-experimental study 104 male patients aged 65.7 +/- 5.5 years suffering asbestosis carried out over a period of three weeks 5 times weekly 6 h at a time phase 1 of the OMR consisting of evidence-based contents of the pulmonary rehabilitation. Directly after that further therapeutic applications with the main focus on exercise therapy and sports were applied over a period of 12 weeks one time weekly 3 h at a time (phase 2). After phase 2 the rehabilitation centre led the patients into sports groups near at place of residence (phase 3). The effects of the OMR were evaluated at the beginning (T1), at the end of phase 1 (T2) and phase 2 (T3) as well as 6 (T4) and 18 months (T5) after T3 by means of a suitable assessment. Results Compared to T1 physical fitness (6-minute Walk Test, Hand-Force Test, PWC Test) as well as health-related quality of life (SF-36) of the patients were significantly improved in T2. Whereas the parameter "vital capacity" and "forced expiratory volume" showed no change over the period of investigation data of "oxygen partial pressure" was significantly increased, too. These positive effects could be confirmed in T3. 82 patients (79%) were doing sports due to health regularly still 6 and 18 months after T3 and could preserve their health outcome in T4 and T5, while the effects of rehabilitation of the 22 patients breaking off any sporting activities wore off again to and even below starting condition in T1. Conclusions In spite of a restrictive pulmonary disease specific exercise therapy and sports are able to mobilize physical reserves of performance and induce an increasing quality of life as well as a higher resilience in activities of daily living. These positive effects could be stabilized persistently by a regular training one time weekly. That way the results emphasize the necessity to put strategies of aftercare into the concept of rehabilitation.

The out-patient department of the Bremen trauma clinic and rehabilitation center (which falls under the auspices of the Association of German Employers’ Liability Insurance Providers) has been developing instruments for a systematic change in the method of orthopaedic shoe provision since 2003. The formerly customary supply of made-to-measure footwear based purely on skilled manual production has been replaced by a phased supply model that also includes a three-dimensional scanning process. In the course of a pilot scheme, findings from 500 insurants from the Employers’ Liability Insurance for the construction industry have shown a considerable optimisation potential in terms of cost effectiveness, quality and satisfaction among insurants. Meanwhile, over 6000 supplies to insurants from all accident insurers have been made on the basis of this phased model (Bremer Modell) all over Germany. Moreover, cost and quality awareness has increased substantially among accident insurers.

PURPOSE: Assessment of the effectiveness of an aquatic functional training in the rehabilitation of conservatively treated diseases of the rotator cuff due to degeneration. MATERIALS AND METHODS: In the frame of a comparative study for evaluation of three kinds of physical treatment the functional adaptations of 42 male patients aged 52-62 years were investigated. The patients were randomised into three treatment groups carried out an ambulant therapy programme with physical applications five times weekly each time 60 min over a period of 10 weeks. The standard group got the physical applications only. The programme of the land group was supplemented by a muscle training on machines for 60 min per therapy unit. The water group carried out additionally an aquatic functional training each time twice 30 min. The three groups were tested at the beginning (T1), at the end (T2) and three months after T2 (T3). RESULTS: In comparison with results in T1 the data obtained demonstrated significant improvements for the dynamic maximum strength in internal and external rotation, the functional status of the shoulder (Constant score) and the health-related quality of life (SF-36) in all groups both in T2 and mainly in T3. The strongest as well as most stabilized positive effects of the intervention carried out were evaluated for the patients in the water group. CONCLUSIONS: The accomodatic resistance and the physical properties of the medium water induce strengthening of the muscles in a gentle way and an improved function of the shoulder. The aquatic functional training does not represent only an alternative kind of treatment, but seems to be one of the most promising methods in the therapy of the conservatively treated diseases of the rotator cuff. Further investigations have to evaluate long-term effects.

In this study we compared the efficacy of integrated cognitive restructuring plus exposure with exposure alone in the treatment of social anxiety disorder (social phobia). Compared to a wait-list control condition, both treatments resulted in significant improvements and maintained their effects on some dependent variables. Although no significant differences were found between the effects of the two active treatments, effect size analysis did suggest certain effect differences.

BACKGROUND Measurement of regional atrophy of the corpus callosum and cortical grey matter may differentiate between primary loss of intracortical projecting neurons and primary fibre degeneration in Alzheimer's disease (AD) and vascular dementia (VD). METHODS The regional corpus callosum area and cortical grey matter volumes were measured in 30 patients with the clinical diagnosis of probable AD, 20 patients with the clinical diagnosis of probable VD and 24 healthy elderly control subjects using MRI in two centers in Munich and Amsterdam. RESULTS Patients with AD showed significantly reduced volumes of cortical grey matter in all cerebral lobes and atrophy of anterior and posterior corpus callosum areas. In VD patients only occipital lobe grey matter volume and anterior corpus callosum area were significantly reduced. In AD patients reduction of cortical grey matter volumes was significantly correlated with regional reductions of corpus callosum areas, but not in VD patients or controls. CONCLUSION These findings support the notion that measurement of the corpus callosum and cortical grey matter atrophy may identify the underlying causes of cortical disconnection in AD and VD and may be helpful to differentiate between both conditions.

BACKGROUND: Doctors are often confronted with end-of-life decisions. When deciding on the withdrawal of medical treatment physicians have to consider the legal position. This study was done to evaluated how far doctors at the university medical center in Dusseldorf had acted in conformity with the established case law in Germany. METHODS: Between April and August 2006 doctors at the university medical center in Dusseldorf filled in a standardized questionnaire about the decisions they had taken to withdraw life-support treatment. RESULTS: 128 of a total of 512 doctors questioned replied (25 %; 32,8 % females and 67,2 % males) . The survey showed that the judicial decision (that it is not necessary to provide treatment if life-support measures are not indicated) is largely determined by non-medical criteria. The clinical decision by doctors depended mainly on his personal opinion. Furthermore the survey showed that only a few doctors made use of the - lawful - option to withdraw medical treatment when this was not indicated. Finally the survey revealed that, in case of conflict between indication and perceived patients’ wishes, the vast majority of doctors behaved in contravention of the decisions established by case law. CONCLUSION: There is the need to discuss what non-medical issues should be taken into account when determining the indication of withdrawal of life-support measures. The results also highlighted the uncertainties that exist regarding a doctor’s decisions about it. Not only should legislation clarify whether "passive euthanasia” is allowed, but it would also be useful to delegate end-of-life decisions to a review board.

The relationship between aflatoxin B1 and G1 was examined in samples from 199 aflatoxin contaminated lots of inshell Brazil nuts imported to Europe. In most of the samples, the relationship between B1 and G1 were approximately 50/50 indicating that the major responsible aflatoxin producing fungi cannot be Aspergillus flavus, which produces solely B aflatoxins. Fungal strains were isolated from two batches of Brazil nuts and isolates of both A. nomius and A. flavus could be identified. The A. nomius isolates were good producers of both B and G aflatoxins, while the A. flavus strains only produced B aflatoxins. In conclusion, this study suggests that A. nomius is an important producer of aflatoxins in Brazil nuts and that its occurrence, and possibly other B and G aflatoxin producers, should be further examined since this may influence strategies for prevention and control of aflatoxins in Brazil nuts.

The ionization dynamics of He nanodroplets irradiated with intense femtosecond extreme ultraviolet pulses of up to 10(13) W/cm(2) power density have been investigated by photoelectron spectroscopy. Helium droplets were resonantly excited to atomiclike 2p states with a photon energy of 21.4 eV, below the ionization potential (I-p), and directly into the ionization continuum with 42.8 eV photons. While electron emission following direct ionization above I-p is well explained within a model based on a sequence of direct electron emission events, the resonant excitation provides evidence of a new, collective ionization mechanism involving many excited atomiclike 2p states. With increasing power density the direct photoline due to an interatomic Coulombic decay disappears. It indicates that ionization occurs due to energy exchange between at least three excited atoms proceeding on a femtosecond time scale. In agreement with recent theoretical work the novel ionization process is very efficient and it is expected to be important for many other systems.

This is an Open Access article distributed under the terms of Creative Commons Attribution Licence 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.; International audience; In this work we present the results from two experiments dedicated to search for quadrupole-collective isovector valence-shell excitation, the states with so-called mixed proton-neutron symmetry (MSS), in nuclei around the doubly magic nucleus $^{208}$Pb. $^{212}$Po was studied in an α-transfer reaction. $^{204}$Hg was studied in an inverse kinematics Coulomb excitation reaction on a carbon target. Both experiments provide indications for existence of one-phonon MSSs. Those are the first experimentally identified MSSs in the mass A ≈ 208 region.

Ionization dynamics of resonantly excited helium nanodroplets have been studied by intense XUV light. By doping the nanodroplets with atoms that either attach to the surface or submerge into the center of the droplet, one can study the dynamics of excitation and ionization through the droplet. When resonantly exciting the droplet, we observe a strong ionization enhancement for atoms attached to the surface. On the other hand, atoms embedded inside the nanodroplet are less efficiently ionized. We attribute this effect to an ultrafast energy transfer to the surface of the droplet and subsequent Penning ionization of the surface-bound dopant.

Hot molecular cores (HMCs) are intermediate stages of high-mass star formation and are also known for their rich emission line spectra at (sub-)mm wavebands. The observed spectral feature of HMCs such as total number of emission lines and associated line intensities are also found to vary with evolutionary stages. We developed various 3D models for HMCs guided by the evolutionary scenarios proposed by recent empirical and modeling studies. We then investigated the spatio-temporal variation of temperature and molecular abundances in HMCs by consistently coupling gas-grain chemical evolution with radiative transfer calculations. We explored the effects of varying physical conditions on molecular abundances including density distribution and luminosity evolution of the central protostar(s). The time-dependent temperature structure of the hot core models provides a realistic framework for investigating the spatial variation of ice mantle evaporation as a function of evolutionary timescales. With increasing protostellar luminosity, the water ice evaporation font ($\sim$100K) expands and the spatial distribution of gas phase abundances of these COMs also spreads out. We simulated the synthetic spectra for these models at different evolutionary timescales to compare with observations. A qualitative comparison of the simulated and observed spectra suggests that these self-consistent hot core models can reproduce the notable trends in hot core spectral variation within the typical hot core timescales of 10$^{5}$ year. These models predict that the spatial distribution of various emission line maps will also expand with evolutionary time. The model predictions can be compared with high resolution observation that can probe scales of a few thousand AU in high-mass star forming regions such as from ALMA.[Abridged], Comment: accepted for publication in A&A

New γγ -coincidence relations and E 2 decay transition rates in the isotopes 194,196 Pt have been deduced from γ -ray spectroscopy experiments using the Gammasphere spectrometer in projectile-Coulomb excitation reactions of beams of 194,196 Pt ions provided by the ATLAS accelerator facility. The results give access to observables that are crucial for a classification of excited quadrupole-collective states in terms of quantum numbers associated with the analytically solvable O(6) dynamical symmetry of the interacting boson model. The data on 196 Pt corroborate the qualitative pattern of excitation energies and E 2 transition rates expected from the O(6) solution but the excitation energies significantly deviate from it on a quantitative level.

The eXtended CASA Line Analysis Software Suite (XCLASS) is a toolbox for the Common Astronomy Software Applications package (CASA) containing new functions for modeling interferometric and single dish data. Among the tools is the myXCLASS program which calculates synthetic spectra by solving the radiative transfer equation for an isothermal object in one dimension, whereas the finite source size and dust attenuation are considered as well. Molecular data required by the myXCLASS program are taken from an embedded SQLite3 database containing entries from the Cologne Database for Molecular Spectroscopy CDMS) and JPL using the Virtual Atomic and Molecular Data Center (VAMDC) portal. Additionally, the toolbox provides an interface for the model optimizer package Modeling and Analysis Generic Interface for eXternal numerical codes (MAGIX), which helps to find the best description of observational data using myXCLASS (or another external model program), i.e., finding the parameter set that most closely reproduces the data., Comment: 18 pages, 10 figures

We have studied fluorescence spectra of small Xem and Xem(NF3)k clusters (m,k⩽102) embedded in large host Ne7500 clusters, excited with SR excitation in the VUV spectral region above the Xe+(P1∕22) atomic limit. The IR emission bands due to ionic chromophores Xep+ (p=2,3,4) as well as UV (B–X) and visible (C–A) bands due to desorbed Xe+F− excimer molecules have been observed. The triatomic Xe2F excimer emission has only been observed under low-energy excitation close to the lowest xenon exciton absorption band. A competition between ionic and charge-transfer reaction channels is followed as a function of the cluster sizes m and k.

In order to investigate the cross-cultural reliability and independence of subscales of the Survey of Personal Beliefs (SPB) data from 751 undergraduate Psychology students (189 White South African students, 114 Black South African students, 262 Mexican students and 186 American students) were compared. Coefficient alphas for the subscales in all samples were low, ranging from .33 to .76. However, alphas for the total scale across all subgroups were high. A comparison of the rank ordering of alpha coefficients for subscales in the different samples partially supported the cross-cultural reliability of the SPB for White South African and Mexican students, and for Black South African and American students. The similarities across samples regarding intercorrelations and shared variance between subscales also provided some evidence for the possible cross-cultural independence of subscales of the SPB. Comparison of total and mean subscale scores showed no significant differences between males and females within samples. However, a significant effect for culture, with significant between-subject effects for all the subscales as well as for the total score, was found. This may be indicative of real differences in irrational belief styles between the groups or may be a result of the insufficient cross-cultural reliability of the SPB.

The Irrational Beliefs Inventory gives a measure of irrational beliefs, as postulated by Ellis's Rational Emotive Behavior therapy. Given the increasing cross-cultural use of psychometric scales, it is important to assess whether the psychometric properties of the inventory are consistent across cultures. In the present study cross-cultural applicability, in terms of internal consistency and independence of subscales, was investigated for an ad hoc sample of White ( n = 100, M age = 21.3 yr., SD = 4.0) and Black ( n = 82, M age = 19.8 yr., SD = 2.2) undergraduate South African university students. Cronbach coefficients alpha for the subscales and Pearson correlations between subscales for American and Dutch students, as reported by Bridges and Sanderman, were compared with those indices for the South African students. The magnitude and rank order of Cronbach α, as well as the correlations between subscales for the three groups showed strong similarities. Values of alpha for the Black South African students were lower in magnitude on all subscales than those for American, Dutch, and White South African samples, but intercorrelations between subscale scores were consistent. Findings in the present study are supportive of the cross-cultural applicability of the Irrational Beliefs Inventory to White South African students but not to South African Black students.