884 research outputs found
Biolandwirtschaft senkt die externen Kosten
Die österreichische Landwirtschaft verursacht jĂ€hrlich externe Kosten von etwa 1,3 Milliarden Euro. Weil der Biolandbau diese um etwa ein Drittel reduzieren kann, muss er stĂ€rker gefördert werden. Nötig sind auĂerdem eine Stickstoff-, Energie- und Pestizidsteuer sowie ein langfristiges politisches Bekenntnis zur Ăkolandwirtschaft
Functional central limit theorems for persistent Betti numbers on cylindrical networks
We study functional central limit theorems for persistent Betti numbers
obtained from networks defined on a Poisson point process. The limit is formed
in large volumes of cylindrical shape stretching only in one dimension. The
results cover a directed sublevel-filtration for stabilizing networks and the
Cech and Vietoris-Rips complex on the random geometric graph.
The presented functional central limit theorems open the door to a variety of
statistical applications in topological data analysis and we consider
goodness-of-fit tests in a simulation study
Synthesis, crystal structures and properties of polymorphic and isomeric nickel(II)thiocyanate coordination compounds with 3-Bromopyridine as coligand
Synthesis, crystal structure and thermal properties of bis(acetonitrile-ÎșN)bis(3-bromopyridine-ÎșN)bis(thiocyanato-ÎșN)cobalt(II)
Funding Information: Financial support by the State of Schleswig-Holstein and the Deutsche Forschungsgemeinschaft is gratefully acknowledged. Funding for this research was provided by: Deutsche Forschungsgemeinschaft (grant No. NA 720/5-2).Peer reviewedPublisher PD
Syntheses, crystal structures and properties of tetraÂkisÂ(3-methylÂpyridine-ÎșN)bisÂ(isoÂthioÂcyanato-ÎșN)manganese(II) and tetraÂkisÂ(3-methylÂpyridine-ÎșN)bisÂ(isoÂthioÂcyanato-ÎșN)iron(II)
The reaction of Mn(NCS) or Fe(NCS) with 3-methylpyridine (CHN) leads to the formation of two isostructural compounds with compositions [Mn(NCS)(CHN)] () and [Fe(NCS)(CHN)] (). IR spectroscopic investigations indicate that only terminally coordinated thiocyanate anions are present. This is confirmed by single-crystal structure analysis, which shows that their crystal structures consist of discrete centrosymmetric complexes, in which the metal cations are octahedrally coordinated by two N-bonded thiocyanate anions and four 3-methylpyridine ligands. X-ray powder diffraction (XRPD) proves that pure samples have been obtained. Thermogravimetric measurements show that decomposition starts at about 90C and that the two coligands are removed in one step for whereas for no clearly resolved steps are visible. XRPD measurements of the residue obtained after the first mass loss of show that a new and unknown crystalline compound has been formed
Spatiotemporal dynamics of feature-based attention spread: evidence from combined electroencephalographic and magnetoencephalographic recordings
Attentional selection on the basis of nonspatial stimulus features induces a sensory gain enhancement by increasing the firing-rate of individual neurons tuned to the attended feature, while responses of neurons tuned to opposite feature-values are suppressed. Here we recorded event-related potentials (ERPs) and magnetic fields (ERMFs) in human observers to investigate the underlying neural correlates of feature-based attention at the population level. During the task subjects attended to a moving transparent surface presented in the left visual field, while task-irrelevant probe stimuli executing brief movements into varying directions were presented in the opposite visual field. ERP and ERMF amplitudes elicited by the unattended task-irrelevant probes were modulated as a function of the similarity between their movement direction and the task-relevant movement direction in the attended visual field. These activity modulations reflecting globally enhanced processing of the attended feature were observed to start not before 200 ms poststimulus and were localized to the motion-sensitive area hMT. The current results indicate that feature-based attention operates in a global manner but needs time to spread and provide strong support for the feature-similarity gain model
Task-load-dependent activation of dopaminergic midbrain areas in the absence of reward
Dopamine release in cortical and subcortical structures plays a central role in reward-related neural processes. Within this context, dopaminergic inputs are commonly assumed to play an activating role, facilitating behavioral and cognitive operations necessary to obtain a prospective reward. Here, we provide evidence from human fMRI that this activating role can also be mediated by task-demand-related processes and thus extendsbeyondsituationsthatonlyentailextrinsicmotivatingfactors. Using a visual discrimination task in which varying levels of task demands were precued, we found enhanced hemodynamic activity in the substantia nigra (SN) for high task demands in the absence of reward or similar extrinsic motivating factors. This observation thus indicates that the SN can also be activated in an endogenous fashion. In parallel to its role in reward-related processes, reward-independent activation likely serves to recruit the processing resources needed to meet enhanced task demands. Simultaneously, activity in a wide network of cortical and subcortical control regions was enhanced in response to high task demands, whereas areas of the default-mode network were deactivated more strongly. The present observations suggest that the SN represents a core node within a broader neural network that adjusts the amount of available neural and behavioral resources to changing situational opportunities and task requirements, which is often driven by extrinsic factors but can also be controlled endogenously
Crystal structure of diÂethanoÂlbis(thioÂcyanato)Âbis(urotropine)cobalt(II) and tetraÂethanoÂlbis(thioÂcyanato)Âcobalt(II)âurotropine (1/2)
The reaction of one equivalent Co(NCS) with four equivalents of urotropine (hexamethylenetetramine) in ethanol leads to the formation of two compounds, namely, bis(ethanol-O)bis(thiocyanato-N)bis(urotropine-N)cobalt(II), [Co(NCS)(CHN)(CHO)] (), and tetrakis(ethanol-O)bis(thiocyanato-N)cobalt(II)âurotropine (1/2), [Co(NCS)(CHO)]2CHN (). In , the Co cations are located on centers of inversion and are sixfold coordinated by two terminal N-bonded thiocyanate anions, two ethanol and two urotropine ligands whereas in the cobalt cations occupy position Wyckoff position c and are sixfold coordinated by two anionic ligands and four ethanol ligands. Compound contains two additional urotropine solvate molecules per formula unit, which are hydrogen bonded to the complexes. In both compounds, the building blocks are connected via intermolecular OâHN ( and ) and CâHS () hydrogen bonding to form three-dimensional networks
Safety of autologous bone marrow aspiration concentrate transplantation: initial experiences in 101 patients
The clinical application of cellular based therapies with ex vivo cultivation for the treatment of diseases of the musculoskeletal system has until now been limited. In particular, the advanced laboratory and technical effort necessary, regulatory issues as well as high costs are major obstacles. On the other hand, newly developed cell therapy systems permit intra-operative enrichment and application of mesenchymal and progenitor stem cells from bone marrow aspirate concentrate (BMAC) in one single operative session. The objective of the present clinical surveillance study was to evaluate new bone formation after the application of BMAC as well as to record any possible therapy-specific complication
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