4,388 research outputs found
Proximate and ultimate aspects of androgen-mediated maternal effects in relation to sibling competition in birds
Proximate and ultimate aspects of androgen-mediated maternal effects in relation to sibling competition in birds
Proximate and ultimate aspects of androgen-mediated maternal effects in relation to sibling competition in birds
Here today, gone tomorrow - adaptation to change in memory-guided visual search
Visual search for a target object can be facilitated by the repeated presentation of an invariant configuration of nontargets ('contextual cueing'). Here, we tested adaptation of learned contextual associations after a sudden, but permanent, relocation of the target. After an initial learning phase targets were relocated within their invariant contexts and repeatedly presented at new locations, before they returned to the initial locations. Contextual cueing for relocated targets was neither observed after numerous presentations nor after insertion of an overnight break. Further experiments investigated whether learning of additional, previously unseen context-target configurations is comparable to adaptation of existing contextual associations to change. In contrast to the lack of adaptation to changed target locations, contextual cueing developed for additional invariant configurations under identical training conditions. Moreover, across all experiments, presenting relocated targets or additional contexts did not interfere with contextual cueing of initially learned invariant configurations. Overall, the adaptation of contextual memory to changed target locations was severely constrained and unsuccessful in comparison to learning of an additional set of contexts, which suggests that contextual cueing facilitates search for only one repeated target location
Haltung von Milchschafen in Deutschland
Es wurde eine Umfrage auf 47 Betrieben mit Milchschafen durchgeführt, davon waren 53 % Biobetriebe. Die Betriebe bewirtschafteten im Median 16 ha und hielten 43 Mutterschafe. Die meisten Betriebe waren spezialisiert auf die Milchschafhaltung. Alle Betriebe verarbeiteten die Schafmilch auf dem Hof. Biobetreite hielten mehr Schafe und erzielten höhere Preise. Die Milchleistung war niedriger, allerdings auch der Kraftfuttereinsatz
Redox-controlled epitaxy and magnetism of oxide heterointerfaces: EuO/SrTiO
We demonstrate a novel route to prepare thin films of the ferromagnetic
insulator Europium monoxide. Key is a redox-controlled interface reaction
between metallic Eu and the substrate SrTiO as the supplier of oxygen. The
process allows tuning the electronic, magnetic and structural properties of the
EuO films. Furthermore, we apply this technique to various oxidic substrates
and demonstrate the universality and limits of a redox-controlled EuO film
synthesis.Comment: 7pages, 6 figures, and supplemetar
Dietary supplementation with β-alanine failed to increase ultimate pH and to improve meat quality in pigs
The non-proteogenic amino acid β-alanine forms part of the dipeptide carnosine (β-alanyl-L-histidine), which exerts pH-buffering, carbonyl scavenging and antioxidant properties [1]. A dietary supplementation with carnosine was shown to increase the pH-value at 45 min, 24 h and 48 h post mortem in the longissimus dorsi of finishing pigs [2]. Furthermore, the antioxidative activity was increased in plasma, liver and muscle [2]. β-alanine has been identified as the rate-limiting precursor for carnosine synthesis and its dietary supplemen-tation increased levels of carnosine in human muscle [1]. We therefore hypothesized that a dietary supplementation of pigs with β-alanine could increase ultimate pH and consequently the quality of pork, particularly its water holding capacity
Functional Diagnosis in Upper and Lower Gastrointestinal Diseases: Relevance for Conservative, Interdisciplinary and Surgical Therapies
Prediction of sound fields in acoustic cavities coupled to absorptive structures due to vibrating surfaces
In the scope of this contribution a model for the Fluid Structure Interaction
(FSI) is presented, where absorptive structures can be considered. A special focus is layed
on the interface coupling modes between absorber and fluid. For the simulation of the
spatial resolution of the sound field within acoustic cavities techniques based on Finite
Element formulations are used. To reduce the number of degrees of freedom a model
reduction method, based on a Component Mode Synthesis (CMS), is applied. The cavity
boundary conditions, e.g. compound absorbers made of homogenous plates and porous
foams, are modeled using Integral Transform Methods (ITM) and appropriate material
formulations. Wavenumber dependent impedances are computed for the absorptive structure
and used for the coupling with the acoustic cavity adding interface coupling modes
for the fluid and applying Hamilton’s principle
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