Finding the First Stars: The Hamburg/ESO Objective Prism Survey

We report on a search for extremely metal-poor ([Fe/H]<-3.0) turnoff stars in the Hamburg/ESO objective prism survey (HES). Metal-poor stars are selected by automatic spectral classification. Extensive simulations show that the selection efficiency for turnoff stars of [Fe/H]25% at B<16.5. Since the HES is more than 1 mag deeper than the HK survey of Beers et al. (1992), the HES offers the possibility to efficiently increase the total number of metal-poor stars by at least a factor of 4.Comment: To appear in: Proceedings of ESO/MPA conference "The First Stars". 2 pages, 1 figur

A suboptimality test for two person zero sum Markov games

This paper presents a games version of the nonoptimality test given by Hastings for Markov decision processes. A pure action will be eliminated if compared to some randomized action it performs worse against any of the opponents possible actions

Efficacy of the long chain alcohol metabolite octanoic acid as an adjunct to standard first line therapy of classical essential tremor

Essential tremor (ET) is a common movement disorder resulting in a postural and kinetic tremor that predominantly affects the upper extremities and varies in amplitude across patients. The etiology of ET is unclear; however, three predominant hypotheses exist. The first hypothesis evaluates rhythmical dysfunction originating from the inferior olivary nucleus that is then propagated throughout the brain and ultimately manifests as tremor. The second hypothesis evaluates γ-aminobutyric acid dysfunction as a causal explanation for ET while the third hypothesis evaluates gross cortical and cerebellar changes that result in ET. The beta-adrenergic blocking medication propranolol and barbiturate primidone are staples for the treatment of this disorder, but often fail to adequately control symptoms. primidone specifically has intolerable side effects for many patients. Ethanol, however, can more effectively treat tremor via a mechanism likely explained by one or more of the aforementioned hypotheses. However, it is not a practical therapeutic option for the treatment of ET primarily as a result of its intoxicating properties among other reasons. Recent attention to the long chain alcohol 1-octanol and its primary metabolite octanoic acid yielded findings of tremorlytic properties, albeit at doses that limit practicality. This study looks to evaluate octanoic acid as an adjunct to primidone and propranolol for the first time and will attempt to demonstrate that as an adjunct, it can be used at lower, more practical doses

Use of soil moisture information in yield models

There are no author-identified significant results in this report

Rabi oscillations between ground and Rydberg states and van der Waals blockade in a mesoscopic frozen Rydberg gas

We present a detailed analysis of our recent observation of synchronous Rabi oscillations between the electronic ground state and Rydberg states in a mesoscopic ensemble containing roughly 100 ultracold atoms [M. Reetz-Lamour \textit{et al.}, submitted, arXiv:0711.4321]. The mesoscopic cloud is selected out of a sample of laser-cooled Rb atoms by optical pumping. The atoms are coupled to a Rydberg state with principal quantum number around 30 by a two-photon scheme employing flat-top laser beams. The influence of residual spatial intensity fluctuations as well as sources of decoherence such as redistribution to other states, radiative lifetime, and laser bandwidth are analysed. The results open up new possibilities for the investigation of coherent many-body phenomena in dipolar Rydberg gases. As an example we demonstrate the van der Waals blockade, a variant of the dipole blockade, for a mesoscopic atom sample

Measurement of the electric dipole moments for transitions to rubidium Rydberg states via Autler-Townes splitting

We present the direct measurements of electric-dipole moments for $5P_{3/2}\to nD_{5/2}$ transitions with $20<n<48$ for Rubidium atoms. The measurements were performed in an ultracold sample via observation of the Autler-Townes splitting in a three-level ladder scheme, commonly used for 2-photon excitation of Rydberg states. To the best of our knowledge, this is the first systematic measurement of the electric dipole moments for transitions from low excited states of rubidium to Rydberg states. Due to its simplicity and versatility, this method can be easily extended to other transitions and other atomic species with little constraints. Good agreement of the experimental results with theory proves the reliability of the measurement method.Comment: 12 pages, 6 figures; figure 6 replaced with correct versio

Premotor Gray Matter Volume is Associated with Clinical Findings in Idiopathic and Genetically Determined Parkinson’s Disease

In the present voxel-based morphometric study, we investigated whether the severity and duration of disease are associated with alterations in gray matter volume (GMV) in symptomatic Parkin mutation carriers (sPARKIN-MC) and patients with idiopathic Parkinson’s disease (iPD). Regression analyses revealed different negative correlations between GMV in cortical motor areas and the severity as well as the disease duration in sPARKIN-MC and iPD patients. SPARKIN-MC showed a less involvement of cortical motor areas, in particular in the supplementary motor area (SMA) than iPD patients. Specifically, in iPD patients, but not in sPARKIN-MC, there was a negative correlation between the SMA degeneration and the UPDRS-II item freezing. The different degeneration patterns may mirror diverse kinetics of the disease progress in these two groups of PD patients with different underlying etiologies