595 research outputs found
First record and establishment of Tuberocephalus (Trichosiphoniella) tianmushanensis Zang, (Hemiptera Aphididae) on ornamental cherry trees in Italy
The occurrence of the Asiatic aphid Tuberocephalus (Trichosiphoniella) tianmushanensis Zang, (=Tuberocephalus (Trichosiphoniella) higansakurae hainnevilleae Remaudière and Sorin) (Hemiptera Aphididae) in Italy is reported. The species was first detected inside leaf galls of Prunus subhirtella cv. pendula trees growing outdoors at the University Botanical Garden of Padua (Italy). Further investigations demonstrated that the species is present in plant nurseries in the Veneto region. So far this species was considered eradicated in Europe, after its first incursion in France in 1993
Decoherence in Ion Trap Quantum Computers
The {\it intrinsic} decoherence from vibrational coupling of the ions in the
Cirac-Zoller quantum computer [Phys. Rev. Lett. {\bf 74}, 4091 (1995)] is
considered. Starting from a state in which the vibrational modes are at a
temperature , and each ion is in a superposition of an excited and a ground
state, an adiabatic approximation is used to find the inclusive probability
for the ions to evolve as they would without the vibrations, and for the
vibrational modes to evolve into any final state. An analytic form is found for
at , and the decoherence time is found for all . The decoherence
is found to be quite small, even for 1000 ions.Comment: 11 pages, no figures, uses revte
ON THE IDENTITY OF THE GENUS LECANOPSIS TARGIONI TOZZETTI
ON THE IDENTITY OF THE GENUS LECANOPSIS TARGIONI TOZZETTI The genus Lecanopsis Targioni Tozzetti was generally accepted by coccidologists until 1994. In that year, on the basis that the exact facies of the genus was not known and that there was no type material, it was proposed that all the species previously included in Lecanopsis be transferred to the genus Paralecanopsis (synonymised with Lecanopsis in 1980) and that only the type species, L. rhyzophila Targioni Tozzetti, be retained in Lecanopsis, thus allowing a proper diagnosis of this group. In order to clarify the identity of the genus Lecanopsis, we have carefully checked the original descriptions of the genus and of its type species by Targioni Tozzetti and by Signoret. This work has highlighted some small mistakes in the translation of the original description from Italian or Latin to French and also some omissions, and these could have led to the conclusion that the real facies of this genus was not known and that the type species, L. rhyzophila, could not be congeneric with the other species currently included in Lecanopsis. However, some original drawings of Lecanopsis by Targioni Tozzetti, which he sent to Signoret in 1872, have been discovered in the Museum Nationale d’Histoire Naturelle, Paris. On the basis of this new information, and with the support of the authoritative opinion of two members of the International Commission of Zoological Nomenclature, we consider that (i) the genus Lecanopsis is a valid genus and propose (ii) that the species of Lecanopsis recently transferred to the genus Paralecanopsis Bodenheimer be re-assigned to the genus Lecanopsis Targioni Tozzetti. Key words: host plants, Asperula, Rhizobium, Rhyzobium, Agropyrum, Aclerda subterranea, Paralecanopsis turcica, Lecanopsis formicarum, history, illustrations, behaviour
Thyroid-specific transcription factors control Hex promoter activity
The homeobox-containing gene Hex is expressed in several cell types, including thyroid follicular cells, in which it regulates the transcription of tissue-specific genes. In this study the regulation of Hex promoter activity was investigated. Using co-transfection experiments, we demonstrated that the transcriptional activity of the Hex gene promoter in rat thyroid FRTL-5 cells is ∼10-fold greater than that observed in HeLa and NIH 3T3 cell lines (which do not normally express the Hex gene). To identify the molecular mechanisms underlying these differences, we evaluated the effect of the thyroid-specific transcription factor TTF-1 on the Hex promoter activity. TTF-1 produced 3-4-fold increases in the Hex promoter activity. Gel-retardation assays and mutagenesis experiments revealed the presence of functionally relevant TTF-1 binding sites in the Hex promoter region. These in vitro data may also have functional relevance in vivo, since a positive correlation between TTF-1 and Hex mRNAs was demonstrated in human thyroid tissues by means of RT-PCR analysis. The TTF-1 effect, however, is not sufficient to explain the difference in Hex promoter activity between FRTL-5 and cells that do not express the Hex gene. For this reason, we tested whether Hex protein is able to activate the Hex promoter. Indeed, co-transfection experiments indicate that Hex protein is able to increase the activity of its own promoter in HeLa cells ∼4-fold. TTF-1 and Hex effects are additive: when transfected together in HeLa cells, the Hex promoter activity is increased 6-7-fold. Thus, the contemporary presence of both TTF-1 and Hex could be sufficient to explain the higher transcriptional activity of the Hex promoter in thyroid cells with respect to cell lines that do not express the Hex gene. These findings demonstrate the existence of direct cross-regulation between thyroid-specific transcription factors
Codes for the Quantum Erasure Channel
The quantum erasure channel (QEC) is considered. Codes for the QEC have to
correct for erasures, i. e., arbitrary errors at known positions. We show that
four qubits are necessary and sufficient to encode one qubit and correct one
erasure, in contrast to five qubits for unknown positions. Moreover, a family
of quantum codes for the QEC, the quantum BCH codes, that can be efficiently
decoded is introduced.Comment: 6 pages, RevTeX, no figures, submitted to Physical Review A, code
extended to encode 2 qubits, references adde
Lignin biodegradation in pulp-and-paper mill wastewater by selected white rot fungi
An investigation has been carried out to explore the lignin-degrading ability of white rot fungi, as B. adusta and P. crysosporium, grown in different media containing (i) glucose and mineral salts; (ii) a dairy residue; (iii) a dairy residue and mineral salts. Both fungi were then used as inoculum to treat synthetic and industrial pulp-and-paper mill wastewater. On synthetic wastewater, up to 97% and 74% of lignin degradation by B. adusta and P. crysosporium, respectively, have been reached. On industrial wastewater, both fungal strains were able to accomplish 100% delignification in 8-10 days, independent from pH control, with a significant reduction of total organic carbon (TOC) of the solution. Results have confirmed the great biotechnological potential of both B. adusta and P. crysosporium for complete lignin removal in industrial wastewater, and can open the way to next industrial applications on large scale
Holonomic quantum computation with neutral atoms
We propose an all-geometric implementation of quantum computation using
neutral atoms in cavity QED. We show how to perform generic single- and
two-qubit gates, the latter by encoding a two-atom state onto a single,
many-level atom. We compare different strategies to overcome limitations due to
cavity imperfections.Comment: 14 pages, 9 figure
The Bougainvillea mealybug Phenacoccus peruvianus, a rapid invader from South America to Europe
Τα κοκκοειδή έντομα εμφανίζονται συχνά ως εισβολείς σε νέες περιοχές. Το είδος Phenacoccus peruvianus Granara de Willink, 2007, γνωστό και ως ψευδόκοκκος της βουκαμβίλιας παρατηρήθηκε για πρώτη φορά στην Ευρώπη το 1999 στην Ισπανία (Αλμερία) και αργότερα το 2002 στην Ιταλία (Σικελία). Αρχικά το είδος είχε αναγνωριστεί ως Phenacoccus sp. Κατα- γραφές του είδους έγιναν συχνότερες και σε άλλες περιοχές της Ισπανίας (συμπεριλαμβανομέ- νων και των Βελεαρίδων νήσων), στη Μ. Βρετανία, τη Γαλλία (συμπεριλαμβανομένης και της Κορσικής), το Μονακό και την Πορτογαλία. Τα φυτά ξενιστές ήταν στις περισσότερες περι- πτώσεις του γένους Bougainvillea.Scale insects are frequent invaders of new territories. The Bougainvillea mealybug, Phenacoccus peruvianus Granara de Willink, 2007, was recorded in Europe for the first time in 1999 in Spain (Almeria) and later in 2002 in Italy (Sicily). Initially, this unknown species was identified provisionally as Phenacoccus sp. Records of this species became frequent later when it was found in other localities in Spain (including the Balearic Islands), Great Britain, France (including Corsica), Monaco, and Portugal. The host plants of this mealybug were in most cases species of Bougainvillea
Optical Holonomic Quantum Computer
In this paper the idea of holonomic quantum computation is realized within
quantum optics. In a non-linear Kerr medium the degenerate states of laser
beams are interpreted as qubits. Displacing devices, squeezing devices and
interferometers provide the classical control parameter space where the
adiabatic loops are performed. This results into logical gates acting on the
states of the combined degenerate subspaces of the lasers, producing any one
qubit rotations and interactions between any two qubits. Issues such as
universality, complexity and scalability are addressed and several steps are
taken towards the physical implementation of this model.Comment: 16 pages, 3 figures, REVTE
Trapping atoms in the vacuum field of a cavity
The aim of this work is to find ways to trap an atom in a cavity. In contrast
to other approaches we propose a method where the cavity is basically in the
vacuum state and the atom in the ground state. The idea is to induce a spatial
dependent AC Stark shift by irradiating the atom with a weak laser field, so
that the atom experiences a trapping force. The main feature of our setup is
that dissipation can be strongly suppressed. We estimate the lifetime of the
atom as well as the trapping potential parameters and compare our estimations
with numerical simulations.Comment: 8 pages, 8 figure
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