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In einer Evaluation unterschiedlicher Auswahl- und Ausbildungskonzepte der gewerblichen Berufsgenossenschaften (BGen) wurden die Hypothesen geprüft, daß durch Testverfahren auswählende BGen bessere Ausbildungsleistungen erzielen als nur durch Interview auswählende, praxisorientierte Ausbildungen zu schlechteren Prüfungsleistungen führen, zwischen der Ausbildungsleistung und dem Leistungsdruck sowie der Einstellung zur Arbeit ein Zusammenhang besteht und diese Variablen sich daher zur Erhöhung des varianzaufklärenden Werts des zweifach gestuften Faktors Selektion eignen. Für die Wirkung des Faktors Selektion wurde die Praxisorientierung als Moderatorvariable vermutet. Es gelang, 75% aller BGen zu erfassen. Als unabhängige Variable wurde in einem ex-post-facto Design der Faktor Selektion auf den Stufen Interview und Test aufgefaßt. In einem einfaktoriellen univariaten kovarianzanalytischen Modell dienten Leistungsdruck, Einstellung zur Arbeit und Praxisorientierung als Kovariaten. Für jede BG ist die Selektionsmethode und die Praxis der Interviewführung durch schriftliche bzw. telefonische Befragung ermittelt worden. Der Ausbildungserfolg wurde durch die Auswertung eines zentralen Notenarchivs erhoben. Durch einen Fragebogen an die 1994/95 geprüften Personen wurden Leistungsdruck, Praxisorientierung und Einstellung zur Arbeit als Kennwerte für die BG erfaßt. Testverfahren und Interview als Stufen des Faktors Selektion eigneten sich nicht zur Vorhersage des Ausbildungserfolgs. Bei den BGen, die durch Test auswählten, wurde eine deutlich größere Variabilität der Noten nachgewiesen als bei den interviewenden BGen. Eine praxisorientierte Ausbildung ging mit schlechten Prüfungsnoten einher (r = -.13). Es bestand keine Wechselwirkung zwischen Praxisorientierung und Auswahlmethode. Die Aufklärung der Notenvarianz durch die Auswahlmethode konnte durch die Kovariaten nur von 2% auf 3% erhöht werden. Mit Einstellung zur Arbeit und Praxisorientierung als Kovariaten konnten insgesamt 17% Varianz aufgeklärt werden. Die Qualität der Messung der Variablen, Gründe für die große Variabilität der Noten unter der Testbedingung sowie die Frage nach der Relevanz der Befunde zur Praxisorientierung der Ausbildung wurden diskutiert.
"Von allen Musikern, die heute schaffen - und manche von ihnen sind mir wahrhaft wert - , hat keiner mir mehr gegeben als Gustav Mahler, - Freude und Ergriffenheit, wie ich sie nur den Größten verdanke". Nein, dieser Satz aus der Mahler-Festschrift zu seinem 50. Geburtstag, 1910, stammt nicht von Hugo von Hofmannsthal, wiewohl auch er einen knappen Artikel beisteuerte. Hofmannsthal hat sich keineswegs enthusiastisch über Mahler geäußert, seine Wahrnehmung hat sich hauptsächlich auf Mahlers Tätigkeit als Direktor der Wiener Hofoper (1897-1907) bezogen, mit dem Komponisten Mahler konnte Hofmannsthal nichts anfangen.
Um dieses Nicht-Verhältnis zwischen Mahler und Hofmannsthal genauer zu perspektivieren, bedarf es wohl einer Kontextuierung, einer Rekonstruktion gemeinsamer Horizonte, zumindest ansatzweise. Und dies im Wissen um die sehr ernst zu nehmende Position von Jens Malte Fischer, der in seiner bedeutenden Mahler-Biographie von 2003 erklärt, "die Situationen Hofmannsthals und des erheblich älteren Mahler sind lebensgeschichtlich und individualpsychologisch grundverschieden", um dann aber doch einzuräumen, "die Sensitivität für Krisenerscheinungen der Zeit und der personalen Existenz" sei "vergleichbar".
Background: Multiple sclerosis (MS) is a chronic, inflammatory demyelinating disease of the central nervous system, believed to be triggered by an autoimmune reaction to myelin. Recently, a fundamentally different pathomechanism termed ‘chronic cerebrospinal venous insufficiency’ (CCSVI) was proposed, provoking significant attention in the media and scientific community.
Methods: Twenty MS patients (mean age 42.2±13.3 years; median Extended Disability Status Scale 3.0, range 0–6.5) were compared with 20 healthy controls. Extra- and intracranial venous flow direction was assessed by colour-coded duplex sonography, and extracranial venous cross-sectional area (VCSA) of the internal jugular and vertebral veins (IJV/VV) was measured in B-mode to assess the five previously proposed CCSVI criteria. IJV-VCSA≤0.3 cm2 indicated ‘stenosis,’ and IJV-VCSA decrease from supine to upright position ‘reverted postural control.’ The sonographer, data analyser and statistician were blinded to the patient/control status of the participants.
Results: No participant showed retrograde flow of cervical or intracranial veins. IJV-VCSA≤0.3 cm2 was found in 13 MS patients versus 16 controls (p=0.48). A decrease in IJV-VCSA from supine to upright position was observed in all participants, but this denotes a physiological finding. No MS patient and one control had undetectable IJV flow despite deep inspiration (p=0.49). Only one healthy control and no MS patients fulfilled at least two criteria for CCSVI.
Conclusions: This triple-blinded extra- and transcranial duplex sonographic assessment of cervical and cerebral veins does not provide supportive evidence for the presence of CCSVI in MS patients. The findings cast serious doubt on the concept of CCSVI in MS.
Proteomic profiles of myocardial tissue in two different etiologies of heart failure were investigated using high performance liquid chromatography (HPLC)/Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Right atrial appendages from 10 patients with hemodynamically significant isolated aortic valve disease and from 10 patients with isolated symptomatic coronary heart disease were collected during elective cardiac surgery. As presented in an earlier study by our group (Baykut et al., 2006), both disease forms showed clearly different pattern distribution characteristics. Interesting enough, the classification patterns could be used for correctly sorting unknown test samples in their correct categories. However, in order to fully exploit and also validate these findings there is a definite need for unambiguous identification of the differences between different etiologies at molecular level. In this study, samples representative for the aortic valve disease and coronary heart disease were prepared, tryptically digested, and analyzed using an FT-ICR MS that allowed collision-induced dissociation (CID) of selected classifier masses. By using the fragment spectra, proteins were identified by database searches. For comparison and further validation, classifier masses were also fragmented and analyzed using HPLC-/Matrix-assisted laser desorption ionization (MALDI) time-of-flight/time-of-flight (TOF/TOF) mass spectrometry. Desmin and lumican precursor were examples of proteins found in aortic samples at higher abundances than in coronary samples. Similarly, adenylate kinase isoenzyme was found in coronary samples at a higher abundance. The described methodology could also be feasible in search for specific biomarkers in plasma or serum for diagnostic purposes.
The pT-differential inclusive production cross section of the prompt charm-strange meson Ds+ in the rapidity range |y|<0.5 was measured in proton–proton collisions at s=7 TeV at the LHC using the ALICE detector. The analysis was performed on a data sample of 2.98×108 events collected with a minimum-bias trigger. The corresponding integrated luminosity is Lint=4.8 nb−1. Reconstructing the decay Ds+→ϕπ+, with ϕ→K−K+, and its charge conjugate, about 480 Ds± mesons were counted, after selection cuts, in the transverse momentum range 2<pT<12 GeV/c. The results are compared with predictions from models based on perturbative QCD. The ratios of the cross sections of four D meson species (namely D0, D+, D⁎+ and Ds+) were determined both as a function of pT and integrated over pT after extrapolating to full pT range, together with the strangeness suppression factor in charm fragmentation. The obtained values are found to be compatible within uncertainties with those measured by other experiments in e+e−, ep and pp interactions at various centre-of-mass energies.
The ALICE Collaboration has measured inclusive J/ψ production in pp collisions at a center-of-mass energy √s=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are Linte=1.1 nb−1 and Lintμ=19.9 nb−1, and the corresponding signal statistics are NJ/ψe+e−=59±14 and NJ/ψμ+μ−=1364±53. We present dσJ/ψ/dy for the two rapidity regions under study and, for the forward-y range, d2σJ/ψ/dydpt in the transverse momentum domain 0<pt<8 GeV/c. The results are compared with previously published results at s=7 TeV and with theoretical calculations.
The ALICE experiment has measured low-mass dimuon production in pp collisions at √s=7 TeV in the dimuon rapidity region 2.5<y<4. The observed dimuon mass spectrum is described as a superposition of resonance decays (η,ρ,ω,η′,ϕ) into muons and semi-leptonic decays of charmed mesons. The measured production cross sections for ω and ϕ are σω(1<pt<5 GeV/c,2.5<y<4)=5.28±0.54(stat)±0.49(syst) mb and σϕ(1<pt<5 GeV/c,2.5<y<4)=0.940±0.084(stat)±0.076(syst) mb. The differential cross sections d2σ/dydpt are extracted as a function of pt for ω and ϕ. The ratio between the ρ and ω cross section is obtained. Results for the ϕ are compared with other measurements at the same energy and with predictions by models.
Identical neutral kaon pair correlations are measured in √s=7 TeV pp collisions in the ALICE experiment. One-dimensional Ks0Ks0 correlation functions in terms of the invariant momentum difference of kaon pairs are formed in two multiplicity and two transverse momentum ranges. The femtoscopic parameters for the radius and correlation strength of the kaon source are extracted. The fit includes quantum statistics and final-state interactions of the a0/f0 resonance. Ks0Ks0 correlations show an increase in radius for increasing multiplicity and a slight decrease in radius for increasing transverse mass, mT, as seen in ππ correlations in pp collisions and in heavy-ion collisions. Transverse mass scaling is observed between the Ks0Ks0 and ππ radii. Also, the first observation is made of the decay of the f2′(1525) meson into the Ks0Ks0 channel in pp collisions.
Heavy flavour decay muon production at forward rapidity in proton–proton collisions at √s=7 TeV
(2012)
The production of muons from heavy flavour decays is measured at forward rapidity in proton–proton collisions at √s=7 TeV collected with the ALICE experiment at the LHC. The analysis is carried out on a data sample corresponding to an integrated luminosity Lint=16.5 nb−1. The transverse momentum and rapidity differential production cross sections of muons from heavy flavour decays are measured in the rapidity range 2.5<y<4, over the transverse momentum range 2<pt<12 GeV/c. The results are compared to predictions based on perturbative QCD calculations.
Harmonic decomposition of two particle angular correlations in Pb–Pb collisions at √sNN=2.76 TeV
(2012)
Angular correlations between unidentified charged trigger (t) and associated (a) particles are measured by the ALICE experiment in Pb–Pb collisions at √sNN=2.76 TeV for transverse momenta 0.25<pTt,a<15 GeV/c, where pTt>pTa. The shapes of the pair correlation distributions are studied in a variety of collision centrality classes between 0 and 50% of the total hadronic cross section for particles in the pseudorapidity interval |η|<1.0. Distributions in relative azimuth Δϕ≡ϕt−ϕa are analyzed for |Δη|≡|ηt−ηa|>0.8, and are referred to as “long-range correlations”. Fourier components VnΔ≡〈cos(nΔϕ)〉 are extracted from the long-range azimuthal correlation functions. If particle pairs are correlated to one another through their individual correlation to a common symmetry plane, then the pair anisotropy VnΔ(pTt,pTa) is fully described in terms of single-particle anisotropies vn(pT) as VnΔ(pTt,pTa)=vn(pTt)vn(pTa). This expectation is tested for 1⩽n⩽5 by applying a global fit of all VnΔ(pTt,pTa) to obtain the best values vn{GF}(pT). It is found that for 2⩽n⩽5, the fit agrees well with data up to pTa∼3–4 GeV/c, with a trend of increasing deviation as pTt and pTa are increased or as collisions become more peripheral. This suggests that no pair correlation harmonic can be described over the full 0.25<pT<15 GeV/c range using a single vn(pT) curve; such a description is however approximately possible for 2⩽n⩽5 when pTa<4 GeV/c. For the n=1 harmonic, however, a single v1(pT) curve is not obtained even within the reduced range pTa<4 GeV/c.