43 research outputs found

    Arbuscular mycorrhizal community composition associated with two plant species in a grassland ecosystem

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    Arbuscular mycorrhizal (AM) fungi are biotrophic symbionts colonizing about two-thirds of land plant species and found in all ecosystems. They are of major importance in plant nutrient supply and their diversity is suggested to be an important determinant of plant community composition. The diversity of the AM fungal community composition in the roots of two plant species (Agrostis capillaris and Trifolium repens) that co-occurred in the same grassland ecosystem was characterized using molecular techniques. We analysed the small subunit (SSU) ribosomal RNA gene amplified from a total root DNA extract using AM fungal-specific primers. A total of 2001 cloned fragments from 47 root samples obtained on four dates were analysed by restriction fragment length polymorphism, and 121 of them were sequenced. The diversity found was high: a total of 24 different phylotypes (groups of phylogenetically related sequences) colonized the roots of the two host species. Phylogenetic analyses demonstrate that 19 of these phylotypes belonged to the Glomaceae, three to the Acaulosporaceae and two to the Gigasporaceae. Our study reveals clearly that the AM fungal community colonizing T. repens differed from that colonizing A. capillaris, providing evidence for AM fungal host preference. In addition, our results reveal dynamic changes in the AM fungal community through time

    Quantum Communication Protocol Employing Weak Measurements

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    We propose a communication protocol exploiting correlations between two events with a definite time-ordering: a) the outcome of a {\em weak measurement} on a spin, and b) the outcome of a subsequent ordinary measurement on the spin. In our protocol, Alice, first generates a "code" by performing weak measurements on a sample of N spins. The sample is sent to Bob, who later performs a post-selection by measuring the spin along either of two certain directions. The results of the post-selection define the "key', which he then broadcasts publicly. Using both her previously generated code and this key, Alice is able to infer the {\em direction} chosen by Bob in the post-selection. Alternatively, if Alice broadcasts publicly her code, Bob is able to infer from the code and the key the direction chosen by Alice for her weak measurement. Two possible experimental realizations of the protocols are briefly mentioned.Comment: 5 pages, Revtex, 1 figure. A second protocol is added, where by a similar set of weak measurement Alice can send, instead of receiving, a message to Bob. The security question for the latter protocol is discusse

    False Beliefs About Asylum Seekers to Australia: The Role of Confidence in Such Beliefs, Prejudice, and the Third Person Effect

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    There has been much controversy about the treatment of asylum seekers in Australia in recent years, with the Australian Government continuing to enforce a very hard-line stance on asylum seekers who arrive to Australia by boat. The present study examined attitudes towards asylum seekers using 164 Australian community members during June 2015 by way of questionnaire. Our primary research question involved how five variables predicted false beliefs about asylum seekers. Specifically, we measured prejudice, the third-person effect, and confidence in the answers given to false beliefs about asylum seekers. Regression results indicated that the main predictors of false beliefs were right-wing political orientation, prejudice, confidence in espousing false beliefs, and the third-person effect (politicians). Furthermore, most of our community participants accepted a large number of false beliefs as being true, with approximately two-thirds of our participants scoring above the midpoint. This reflects similar findings over the last decade or so. Our results indicate that, if one believes in bottom-up change, a more nuanced approach needs to be undertaken with community anti-prejudice interventions

    The STAR experiment at the relativistic heavy ion collider

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    Sea surface temperatures of the Aveiro region of the Atlantic Coast of N. Portugal, using AVHRR data

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    The Atlantic coast of Portugal, to the south of Porto, was formed during the Holocene (Rodrigues and Dias 1989) by the accumulation of sand deposits derived principally from the north. This created a linear coast aligned at an angle of 15 degrees to the east of north. The main aim of this work was the study of the physical environment of the offshore system using AVHRR data to examine sea surface temperatures (SST) in the Aveiro region (Portugal), in order to identify, during 1999, the Portuguese coastal upwelling
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