Pre-packaged fresh fish - Searching for quality descriptive criteria

32 Proben verpackten Frischfischs in Selbstbedienungspackungen, 16 Seelachs- und 16 Rotbarschproben aus deutschen Supermärkten wurden mit physikalischen, chemischen, mikrobiellen und sensorischen Methoden untersucht. Ziel der Untersuchung war dieWertung von Untersuchungsmethoden zur Qualitätsbestimmung. Es zeigte sich, daß neben der sensorischen Beurteilung die Bestimmung des TVB-N geeignet ist, die Qualität dieser Produkte zu beurteilen

Effects of changing mosquito host searching behaviour on the cost effectiveness of a mass distribution of long-lasting, insecticidal nets : a modelling study

The effectiveness of long-lasting, insecticidal nets (LLINs) in preventing malaria is threatened by the changing biting behaviour of mosquitoes, from nocturnal and endophagic to crepuscular and exophagic, and by their increasing resistance to insecticides.; Using epidemiological stochastic simulation models, we studied the impact of a mass LLIN distribution on Plasmodium falciparum malaria. Specifically, we looked at impact in terms of episodes prevented during the effective life of the batch and in terms of net health benefits (NHB) expressed in disability adjusted life years (DALYs) averted, depending on biting behaviour, resistance (as measured in experimental hut studies), and on pre-intervention transmission levels.; Results were very sensitive to assumptions about the probabilistic nature of host searching behaviour. With a shift towards crepuscular biting, under the assumption that individual mosquitoes repeat their behaviour each gonotrophic cycle, LLIN effectiveness was far less than when individual mosquitoes were assumed to vary their behaviour between gonotrophic cycles. LLIN effectiveness was equally sensitive to variations in host-searching behaviour (if repeated) and to variations in resistance. LLIN effectiveness was most sensitive to pre-intervention transmission level, with LLINs being least effective at both very low and very high transmission levels, and most effective at around four infectious bites per adult per year. A single LLIN distribution round remained cost effective, except in transmission settings with a pre-intervention inoculation rate of over 128 bites per year and with resistant mosquitoes that displayed a high proportion (over 40%) of determined crepuscular host searching, where some model variants showed negative NHB. Shifts towards crepuscular host searching behaviour can be as important in reducing LLIN effectiveness and cost effectiveness as resistance to pyrethroids. As resistance to insecticides is likely to slow dow the development of behavioural resistance and vice versa, the two types of resistance are unlikely to occur within the same mosquito population. LLINs are likely cost effective interventions against malaria, even in areas with strong resistance to pyrethroids or where a large proportion of host-mosquito contact occurs during times when LLIN users are not under their nets

Hiding in the Shadows: Searching for Planets in Pre--transitional and Transitional Disks

Transitional and pre--transitional disks can be explained by a number of mechanisms. This work aims to find a single observationally detectable marker that would imply a planetary origin for the gap and, therefore, indirectly indicate the presence of a young planet. N-body simulations were conducted to investigate the effect of an embedded planet of one Jupiter mass on the production of instantaneous collisional dust derived from a background planetesimal disk. Our new model allows us to predict the dust distribution and resulting observable markers with greater accuracy than previous work. Dynamical influences from a planet on a circular orbit are shown to enhance dust production in the disk interior and exterior to the planet orbit while removing planetesimals from the the orbit itself creating a clearly defined gap. In the case of an eccentric planet the gap opened by the planet is not as clear as the circular case but there is a detectable asymmetry in the dust disk.Comment: Accepted to ApJL 25th September 2013. 4 figures, 1 tabl

Optimal analysis of azimuthal features in the CMB

We present algorithms for searching for azimuthally symmetric features in CMB data. Our algorithms are fully optimal for masked all-sky data with inhomogeneous noise, computationally fast, simple to implement, and make no approximations. We show how to implement the optimal analysis in both Bayesian and frequentist cases. In the Bayesian case, our algorithm for evaluating the posterior likelihood is so fast that we can do a brute-force search over parameter space, rather than using a Monte Carlo Markov chain. Our motivating example is searching for bubble collisions, a pre-inflationary signal which can be generated if multiple tunneling events occur in an eternally inflating spacetime, but our algorithms are general and should be useful in other contexts.Comment: 30 pages, 5 figure

Variation in pre-laying behaviour of hens : implications for control and motivation

Considerable variation in pre-laying behaviour of domestic hens (Gallus gcillus domesticus) is observed within individuals, between individuals and between different husbandry systems. The contributions o f internal and external factors to this variation were considered. Part o f this variation is in relative amounts o f searching and nesting, so criteria were defined to separate pre-laying behaviour into a searching and sitting phase.The main internal factors considered related to lag and position o f eggs in sequences. The duration o f the sitting phase and the total time spent in the nest box was related to lag. The duration o f pre-laying behaviour was longer for the first egg o f a sequence than for the other eggs. This was mainly due to a longer searching phase in which hens performed more nest examinations. The duration of the sitting phase was longer for the last egg o f a sequence than for other eggs; this may have been related to a longer lag found for the last egg.Effects o f competing behavioural tendencies on pre-laying behaviour involve both internal and external factors. A series o f experiments was conducted to investigate the performance o f pre-laying behaviour while altering the availability o f food and motivation to feed (length of food deprivation). Hens always interrupted their prelaying behaviour in order to feed when food was presented. Length o f deprivation did not influence the duration o f feeding or pre-laying behaviour, that is, even "satiated" hens stopped their pre-laying behaviour and fed. However, the delay in oviposition was found to be greater when food was presented in the later, rather than the earlier, stages of pre-laying behaviour. The duration o f pre-laying behaviour and o f the searching phase was longer if hens were food deprived than if food was available. These findings suggests that the expression o f pre-laying behaviour is determined by the tendency to perform pre-laying behaviour competing with other behavioural tendencies.External factors examined included the effects o f conditions that facilitate searching and nesting behaviour on pre-laying behaviour. Hens provided with an unlittered nest box showed an extended pre-laying behaviour and searching phase, more searching behaviour and nest examinations and more nest entries o f a shorter duration than when provided with a littered nest box. These results suggested that in the absence o f a suitable nest site, hens delayed, and showed an incomplete transition from searching to nesting behaviour. Providing an exploratory walkway to facilitate searching behaviour resulted in the searching phase starting earlier than expected, and in the occurence of more searching behaviour and nest examinations during this time. Environments that facilitate searching behaviour may provide external cues that allow the motivation to perform pre-laying behaviour to be expressed earlier than in barren environments.The strength o f hens' motivation to reach a nest box was assessed with the aid of aversive stimuli. Hens were required to pass through an empty corridor, or past a dominant, subordinate or unfamiliar hen to reach a nest box. Hens delayed their approach to the nest box and made more attempts to find alternative routes to the nest box when required to pass a dominant or unfamiliar hen. Thus social factors were found to influence access to the nest site and pre-laying behaviour. Hens appeared to be only weakly motivated to reach the nest site during the searching phase; motivation to reach the nest site increased near the start o f the sitting phase.The effects o f social interactions on access to a nest site and on the pre-laying behaviour of hens in small groups was investigated. Evidence o f competition for the nest site was found when more than one hen was showing pre-laying behaviour. Subordinate hens walked more in the last hour before oviposition and sat less in the last 25 minutes when other hens were also showing pre-laying behaviour than when no other hens were in the pre-laying phase. Dominant hens in the pre-laying phase remained nearer the nest when other hens were showing pre-laying behaviour than when none were doing so. Thus social interactions during the pre-laying phase result in variation in pre-laying behaviour in both directions; subordinate hens do not settle into the expected nesting phase whereas dominant hens stay nearer the nest.A motivational theory o f pre-laying behaviour is proposed in which pre-laying behaviour is controlled by an interaction between the tendencies to perform searching and nesting behaviour. The tendency to start searching behaviour is influenced by internal factors, competition between motivational systems and external cues for exploration. The tendency to start nesting behaviour is influenced by the availability o f a suitable nest site and social factors. It is suggested that a certain amount o f behavioural priming is normally required before oviposition can occur. The implications o f this model for the welfare of laying hens is discussed

Conserved Quantities in Background Independent Theories

We discuss the difficulties that background independent theories based on quantum geometry encounter in deriving general relativity as the low energy limit. We follow a geometrogenesis scenario of a phase transition from a pre-geometric theory to a geometric phase which suggests that a first step towards the low energy limit is searching for the effective collective excitations that will characterize it. Using the correspondence between the pre-geometric background independent theory and a quantum information processor, we are able to use the method of noiseless subsystems to extract such coherent collective excitations. We illustrate this in the case of locally evolving graphs.Comment: 11 pages, 3 figure