351 research outputs found
Practische Anweisung zur nĂŒzlichsten Magazin-Bienenzucht vor alle Gegenden : wordurch die Bienen in Strohkörben und hölzernen KĂ€sten, durchs SchwĂ€rmen und Ableger machen, ohne zu fĂŒttern, sicher zu vermehren, von ihnen Honig und Wachs, ohne Tödten und Beschneiden zu erlangen ; wo bey richtiger Behandlung, in einem guten Clima, jeder guter Bienenstock jĂ€hrlich 5 Gulden Nutzen bringt, auch bey recht guten Bienen-Jahren solches verdoppelt, und man ihn Lebenslang benutzen kann ; nebst einer Anweisung zu einer nĂŒzlichen Wald-Bienenzucht, welche vor den Grundherrn und Unterthanen vortheilhaft ist ; durch vieljĂ€hrige Erfahrungen geprĂŒft, und zum gemeinen Nutzen herausgegeben
Vollst. Titel: Practische Anweisung zur nĂŒzlichsten Magazin-Bienenzucht vor alle Gegenden : wordurch die Bienen in Strohkörben und hölzernen KĂ€sten, durchs SchwĂ€rmen und Ableger machen, ohne zu fĂŒttern, sicher zu vermehren, von ihnen Honig und Wachs, ohne Tödten und Beschneiden zu erlangen ; wo bey richtiger Behandlung, in einem guten Clima, jeder guter Bienenstock jĂ€hrlich 5 Gulden Nutzen bringt, auch bey recht guten Bienen-Jahren solches verdoppelt, und man ihn Lebenslang benutzen kann ; nebst einer Anweisung zu einer nĂŒzlichen Wald-Bienenzucht, welche vor den Grundherrn und Unterthanen vortheilhaft ist ; durch vieljĂ€hrige Erfahrungen geprĂŒft, und zum gemeinen Nutzen herausgegebe
Band bending inversion in BiSe nanostructures
Shubnikov-de-Haas oscillations were studied under high magnetic field in
BiSe nanostructures grown by Chemical Vapor Transport, for different
bulk carrier densities ranging from to
. The contribution of topological surface states
to electrical transport can be identified and separated from bulk carriers and
massive two-dimensional electron gas. Band bending is investigated, and a
crossover from upward to downward band bending is found at low bulk density, as
a result of a competition between bulk and interface doping. These results
highlight the need to control electrical doping both in the bulk and at
interfaces in order to study only topological surface states.Comment: 6 pages, 4 figure
Studying the ephemeral, cultures of digital oblivion Identifying patterns in Instagram Stories
In diesem Beitrag stellen wir unsere Work-In-Progress Social-Media-Studie zu Instagram-Stories wÀhrend der Bundestagswahl 2021 vor. Da es wenig Daten zu den Inhalten und Elementen der Stories gibt haben wir ein Annotationstool entwickelt, mit dem durch Crowdsourcing Stories auf privaten Profilen und denen von Influencern annotiert und beschrieben werden können. ZusÀtzlich wurden die Stories politischer Parteien und derer Spitzenkandidat*innen automatisiert gesammelt und teilautomatisiert annotiert. Die beiden Korpora werden im weiteren Verlauf miteinander verglichen um zunÀchst auf einer Metaebene unterschiede und parallelen der Story-Nutzung zwischen Privatpersonen und politischer Akteure sowie Influencern zu erfassen. Als Nebeneffekt erhalten wir ein Korpus das es entgegen der vorhandenen Literatur zum ersten Mal erlaubt quantitative Aussagen zu Instagram-Stories machen kann: Welche Elemente und Medien werden genutzt, welche Inhalte geteilt
Basis set convergence in extended systems: infinite hydrogen fluoride and hydrogen chloride chains
Basis set convergence of the Hartree-Fock and the correlation energy is
examined for the hydrogen bonded infinite bent chains (HF)_infinity and
(HCl)_infinity. We employ series of correlation consistent basis sets up to
quintuple zeta quality together with a coupled cluster method (CCSD) to
describe electron correlation on ab initio level. The Hartree-Fock energy
converges rapidly with increasing basis set quality whereas the correlation
energy is found to be slowly convergent for the same series of basis sets. We
study basis set extrapolation for (HF)_infinity and (HCl)_infinity and show
that it substantially enhances the accuracy of both the Hartree-Fock and the
correlation energy in extended systems.Comment: 12 pages, 4 figures, 4 tables, LaTeX, corrected typo
Generation of Complex Azabicycles and Carbobicycles from Two Simple Compounds in a Single Operation through a MetalâFree SixâStep Domino Reaction
Azaâ and carbobicyclic compounds possess favorable pharmaceutical properties, but they are difficult to access. Herein, we demonstrate an unprecedented organocatalytic two component sixâstep chemodivergent domino reaction, which provides a straightforward, sustainable and atom economical route to difficultâtoâaccess complex bicyclic architectures: azabicycles and carbobicycles, whose ratios can be controlled by the applied electrophiles and catalysts. Detailed NMR and Xâray studies on the structures and relative stereochemistry of selected compounds are presented. Mechanistic investigations of the chemoselective branching step have been carried out with DFT methods in conjunction with semiempirical van der Waals interactions. This new domino reaction opens up a new vista of generating, in a single operation, new bioactive compounds with strong antiviral properties (EC50 up to 0.071â
ÎŒm for human cytomegalovirus (HCMV)) outperforming clinically used ganciclovir (EC50 2.6â
ÎŒm).Six steps in one go! An unprecedented two component sixâstep domino reaction, providing a straightforward and atom economical route to bioactive azabicycles and carbobicycles is presented. DFT calculations accounting for dispersion interactions revealed that chemoselectivity might result from small differences in transition state and reaction energies of the branching step. This reaction opens up a new vista of generating, in a single operation, new antivirals outperforming clinically used drugs.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137557/1/chem201504798.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137557/2/chem201504798_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137557/3/chem201504798-sup-0001-misc_information.pd
Blood Pressure in Seizures and Epilepsy
In this narrative review, we summarize the current knowledge of neurally mediated blood pressure (BP) control and discuss how recently described epilepsy- and seizure-related BP alterations may contribute to premature mortality and sudden unexpected death in epilepsy (SUDEP). Although people with epilepsy display disturbed interictal autonomic function with a shift toward predominant sympathetic activity, prevalence of arterial hypertension is similar in people with and without epilepsy. BP is transiently increased in association with most types of epileptic seizures but may also decrease in some, illustrating that seizure activity can cause both a decrease and increase of BP, probably because of stimulation or inhibition of distinct central autonomic function by epileptic activity that propagates into different neuronal networks of the central autonomic nervous system. The principal regulatory neural loop for short-term BP control is termed baroreflex, mainly involving peripheral sensors and brain stem nuclei. The baroreflex sensitivity (BRS, expressed as change of interbeat interval per change in BP) is intact after focal seizures, whereas BRS is markedly impaired in the early postictal period following generalized convulsive seizures (GCS), possibly due to metabolically mediated muscular hyperemia in skeletal muscles, a massive release of catecholamines and compromised brain stem function. Whilst most SUDEP cases are probably caused by a cardiorespiratory failure during the early postictal period following GCS, a profoundly disturbed BRS may allow a life-threatening drop of systemic BP in the aftermath of GCS, as recently reported in a patient as a plausible cause of SUDEP in a few patients
Early and Differential Diagnosis of Dementia and Mild Cognitive Impairment Design and Cohort Baseline Characteristics of the German Dementia Competence Network
Background: The German Dementia Competence Network (DCN) has established procedures for standardized multicenter acquisition of clinical, biological and imaging data, for centralized data management, and for the evaluation of new treatments. Methods: A longitudinal cohort study was set up for patients with mild cognitive impairment (MCI), patients with mild dementia and control subjects. The aims were to establish the diagnostic, differential diagnostic and prognostic power of a range of clinical, laboratory and imaging methods. Furthermore, 2 clinical trials were conducted with patients suffering from MCI and mild to moderate Alzheimer's Disease (AD). These trials aimed at evaluating the efficacy and safety of the combination of galantamine and memantine versus galantamine alone. Results: Here, we report on the scope and projects of the DCN, the methods that were employed, the composition and flow within the diverse groups of patients and control persons and on the clinical and neuropsychological baseline characteristics of the group of 2,113 subjects who participated in the observational and clinical trials. Conclusion: These data have an impact on the procedures for the early and differential clinical diagnosis of dementias, the current standard treatment of AD as well as on future clinical trials in AD. Copyright (C) 2009 S. Karger AG, Base
A Student-t based filter for robust signal detection
The search for gravitational-wave signals in detector data is often hampered
by the fact that many data analysis methods are based on the theory of
stationary Gaussian noise, while actual measurement data frequently exhibit
clear departures from these assumptions. Deriving methods from models more
closely reflecting the data's properties promises to yield more sensitive
procedures. The commonly used matched filter is such a detection method that
may be derived via a Gaussian model. In this paper we propose a generalized
matched-filtering technique based on a Student-t distribution that is able to
account for heavier-tailed noise and is robust against outliers in the data. On
the technical side, it generalizes the matched filter's least-squares method to
an iterative, or adaptive, variation. In a simplified Monte Carlo study we show
that when applied to simulated signals buried in actual interferometer noise it
leads to a higher detection rate than the usual ("Gaussian") matched filter.Comment: 17 pages, 6 figure
"What's (the) Matter?", A Show on Elementary Particle Physics with 28 Demonstration Experiments
We present the screenplay of a physics show on particle physics, by the
Physikshow of Bonn University. The show is addressed at non-physicists aged 14+
and communicates basic concepts of elementary particle physics including the
discovery of the Higgs boson in an entertaining fashion. It is also
demonstrates a successful outreach activity heavily relying on the university
physics students. This paper is addressed at anybody interested in particle
physics and/or show physics. This paper is also addressed at fellow physicists
working in outreach, maybe the experiments and our choice of simple
explanations will be helpful. Furthermore, we are very interested in related
activities elsewhere, in particular also demonstration experiments relevant to
particle physics, as often little of this work is published.
Our show involves 28 live demonstration experiments. These are presented in
an extensive appendix, including photos and technical details. The show is set
up as a quest, where 2 students from Bonn with the aid of a caretaker travel
back in time to understand the fundamental nature of matter. They visit
Rutherford and Geiger in Manchester around 1911, who recount their famous
experiment on the nucleus and show how particle detectors work. They travel
forward in time to meet Lawrence at Berkeley around 1950, teaching them about
the how and why of accelerators. Next, they visit Wu at DESY, Hamburg, around
1980, who explains the strong force. They end up in the LHC tunnel at CERN,
Geneva, Switzerland in 2012. Two experimentalists tell them about colliders and
our heroes watch live as the Higgs boson is produced and decays. The show was
presented in English at Oxford University and University College London, as
well as Padua University and ICTP Trieste. It was 1st performed in German at
the Deutsche Museum, Bonn (5/'14). The show has eleven speaking parts and
involves in total 20 people.Comment: 113 pages, 88 figures. An up to date version of the paper with high
resolution pictures can be found at
http://www.th.physik.uni-bonn.de/People/dreiner/Downloads/. In v2 the
acknowledgements and a citation are correcte
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