5,933 research outputs found
Post-training load-related changes of auditory working memory: An EEG study
Working memory (WM) refers to the temporary retention and manipulation of information, and its capacity is highly susceptible to training. Yet, the neural mechanisms that allow for increased performance under demanding conditions are not fully understood. We expected that post-training efficiency in WM performance modulates neural processing during high load tasks. We tested this hypothesis, using electroencephalography (EEG) (N = 39), by comparing source space spectral power of healthy adults performing low and high load auditory WM tasks. Prior to the assessment, participants either underwent a modality-specific auditory WM training, or a modality-irrelevant tactile WM training, or were not trained (active control). After a modality-specific training participants showed higher behavioral performance, compared to the control. EEG data analysis revealed general effects of WM load, across all training groups, in the theta-, alpha-, and beta-frequency bands. With increased load theta-band power increased over frontal, and decreased over parietal areas. Centro-parietal alpha-band power and central beta-band power decreased with load. Interestingly, in the high load condition a tendency toward reduced beta-band power in the right medial temporal lobe was observed in the modality-specific WM training group compared to the modality-irrelevant and active control groups. Our finding that WM processing during the high load condition changed after modality-specific WM training, showing reduced beta-band activity in voice-selective regions, possibly indicates a more efficient maintenance of task-relevant stimuli. The general load effects suggest that WM performance at high load demands involves complementary mechanisms, combining a strengthening of task-relevant and a suppression of task-irrelevant processing
LIMS: Livestock Information Management System - Introductory guide
This introductory guide has been written to facilitate the use of the LIMS (Livestock Information Management System) package, details of which are given in the system documentation manual. The LIMS system was based on the experience gained from IDEAS (ILCA's Data Entry and Analysis System) a software package designed for the management of animal performance data. This guide takes the reader through the entire features of the LIMS software using sample data sets. The user is most likely to gain if the manual is read while performing the suggested tasks
Alternativen der Kleegrasnutzung in vieharmen und viehlosen Betrieben
Increasing number of stockless organic farms give reason to search for new forms of clover-grass (CG) utilization in order to maintain or increase soil fertility and productivity. A quantitative study was carried out among 93 organic farms to identify different forms of CG utilization and their assets and drawbacks on organic farms.
Different ways of CG transfer such as direct transfer (cut & carry) and indirect transfer stockless farms. In addition, seven farms were interviewed about their experiences
with CG transfer practices. The farmers rate CG transfer mainly positive, since it may partially compensate the negative effects on soil fertility through the missing manure on stockless organic farms. As less than 0.2 LU/ha is found on more than 34% of all organic farms, there is a high relevance for alternative forms of CG usage in order to
ensure the fertility of organic arable farming. However, we also see a high need for research to improve economic conditions of animal husbandry as an integral part of
sustainable organic farming systems
Alternativen der Kleegrasnutzung in vieharmen und viehlosen Betrieben
Increasing number of stockless organic farms give reason to search for new forms of clover-grass (CG) utilization in order to maintain or increase soil fertility and productivity. A quantitative study was carried out among 93 organic farms to identify different forms of CG utilization and their assets and drawbacks on organic farms.
Different ways of CG transfer such as direct transfer (cut & carry) and indirect transfer stockless farms. In addition, seven farms were interviewed about their experiences
with CG transfer practices. The farmers rate CG transfer mainly positive, since it may partially compensate the negative effects on soil fertility through the missing manure on stockless organic farms. As less than 0.2 LU/ha is found on more than 34% of all organic farms, there is a high relevance for alternative forms of CG usage in order to
ensure the fertility of organic arable farming. However, we also see a high need for research to improve economic conditions of animal husbandry as an integral part of
sustainable organic farming systems
Reliability analysis of dynamic systems by translating temporal fault trees into Bayesian networks
Classical combinatorial fault trees can be used to assess combinations of failures but are unable to capture sequences of faults, which are important in complex dynamic systems. A number of proposed techniques extend fault tree analysis for dynamic systems. One of such technique, Pandora, introduces temporal gates to capture the sequencing of events and allows qualitative analysis of temporal fault trees. Pandora can be easily integrated in model-based design and analysis techniques. It is, therefore, useful to explore the possible avenues for quantitative analysis of Pandora temporal fault trees, and we identify Bayesian Networks as a possible framework for such analysis. We describe how Pandora fault trees can be translated to Bayesian Networks for dynamic dependability analysis and demonstrate the process on a simplified fuel system model. The conversion facilitates predictive reliability analysis of Pandora fault trees, but also opens the way for post-hoc diagnostic analysis of failures
Foraging behavior and Doppler shift compensation in echolocating hipposiderid bats, I-Iipposideros bicolor and I-Iipposideros speoris
1. Two hipposiderid bats,H. bicolor andH. speoris, were observed in their natural foraging areas in Madurai (South India). Both species hunt close together near the foliage of trees and bushes but they differ in fine structure of preferred hunting space:H. bicolor hunts within the foliage, especially whenH. speoris is active at the same time, whereasH. speoris never flies in dense vegetation but rather in the more open area (Fig. 1, Table 1).
2. Both species emit CF/FM-sounds containing only one harmonic component in almost all echolocation situations. The CF-parts of CF/FM-sounds are species specific within a band of 127–138 kHz forH. speoris and 147–159 kHz forH. bicolor (Tables 2 and 3).
3. H. speoris additionally uses a complex harmonic sound during obstacle avoidance and during laboratory tests for Doppler shift compensation.H. bicolor consistently emits CF/FM-sounds in these same situations (Fig. 2).
4. Both hipposiderid bats respond to Doppler shifts in the returning echoes by lowering the frequency of the emitted sounds (Fig. 3). However, Doppler compensations are incomplete as the emitted frequencies are decreased by only 55% and 56% (mean values) of the full frequency shifts byH. speoris andH, bicolor, respectively.
5. The differences in Doppler shift compensation, echolocating and hunting behavior suggest thatH. speoris is less specialized on echolocation with CF/FM-sounds thanH. bicolor
Hennessy-Milner Logic with Greatest Fixed Points as a Complete Behavioural Specification Theory
There are two fundamentally different approaches to specifying and verifying
properties of systems. The logical approach makes use of specifications given
as formulae of temporal or modal logics and relies on efficient model checking
algorithms; the behavioural approach exploits various equivalence or refinement
checking methods, provided the specifications are given in the same formalism
as implementations.
In this paper we provide translations between the logical formalism of
Hennessy-Milner logic with greatest fixed points and the behavioural formalism
of disjunctive modal transition systems. We also introduce a new operation of
quotient for the above equivalent formalisms, which is adjoint to structural
composition and allows synthesis of missing specifications from partial
implementations. This is a substantial generalisation of the quotient for
deterministic modal transition systems defined in earlier papers
Linear resolutions of powers and products
The goal of this paper is to present examples of families of homogeneous
ideals in the polynomial ring over a field that satisfy the following
condition: every product of ideals of the family has a linear free resolution.
As we will see, this condition is strongly correlated to good primary
decompositions of the products and good homological and arithmetical properties
of the associated multi-Rees algebras. The following families will be discussed
in detail: polymatroidal ideals, ideals generated by linear forms and Borel
fixed ideals of maximal minors. The main tools are Gr\"obner bases and Sagbi
deformation
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