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Citrus variegation ilarvirus (CVV) is one of the oldest viruses reported in Citrus, which produces crinkling, puckering and variegation of leaves in field trees and, occasionally, variegated and deformed fruits. This virus is primarily transmitted by grafting. However, no consistent data are available concerning CVV seed transmission, which is apparently low. The elimination of CVV in citrus genotypes is carried out by shoot-tip-grafting. In the case of seed sources, virus elimination directly in the seeds becomes essential. In cryotherapy, plant pathogens such as viruses, phytoplasmas and bacteria are eradicated by exposing explants to liquid nitrogen. It allows treatment of a high number of samples and results in a high frequency of pathogen-free regenerants. In this work, three polyembryonic Citrus genotypes (sour orange, mandarin and lemon), which were found infected by CVV, were used for trials of virus seed transmission and CVV elimination by dehydration/cryopreservation of the seeds. The dehydrated seeds were placed in cryovials which were then plunged into liquid nitrogen at -196°C. ISSR markers were used to discriminate between zygotic and nucellar plants after treatment. TAS-ELISA and RT-PCR were applied for CVV detection in the seed components before cryopreservation and in the produced seedlings after treatment. CVV seed transmission was assessed for the first time in sour orange and lemon genotypes by serological and molecular means. All tested Citrus genotypes showed CVV infection in both components of the seed plunged in liquid nitrogen. However, all plantlets developed from cryopreserved seeds were CVV-free 2 years after transplanting.

A cryopreservation procedure by dehydration and direct immersion in liquid nitrogen was developed for seeds of four polyembryonic Citrus species, and the sexual or nucellar origin of the recovered seedlings was investigated. Seeds of three species could be desiccated in a sterile air flow to 16 percent (C. sinensis) or 10 percent (C. aurantium and C. limon) moisture content with a negligible reduction in germination levels. Differently, the germinability of C. deliciosa seeds dropped to 50 percent after drying to 15 percent moisture content. Following dehydration treatments, a reduction in the average number of seedlings per germinated seed was always observed. However, all four species benefited from desiccation in terms of protection during immersion in liquid nitrogen, with C. sinensis and C. aurantium showing the greatest survival (93 percent germination) after cryopreservation. The Inter-Simple Sequence Repeat analysis of seedlings recovered from cryopreserved seeds showed that the dehydration/cryopreservation procedure promotes the germination of zygotic embryos and reduces the number of apomictic seedlings per seed.

The Human Connectome Project (HCP) seeks to map the structural and functional connections between network elements in the human brain. Magnetoencephalography (MEG) provides a temporally rich source of information on brain network dynamics and represents one source of functional connectivity data to be provided by the HCP. High quality MEG data will be collected from 50 twin pairs both in the resting state and during performance of motor, working memory and language tasks. These data will be available to the general community. Additionally, using the cortical parcellation scheme common to all imaging modalities, the HCP will provide processing pipelines for calculating connection matrices as a function of time and frequency. Together with structural and functional data generated using magnetic resonance imaging methods, these data represent a unique opportunity to investigate brain network connectivity in a large cohort of normal adult human subjects. The analysis pipeline software and the dynamic connectivity matrices that it generates will all be made freely available to the research community.

The southern- central Tyrrhenian Sea is a poorly studied area of the Mediterranean Sea, although its importance for the biological fluxes among the western and eastern basins is recognised. This note aimed at evaluating in the waters of the Southern Tyrrhenian Sea the efficiency of some steps of the organic matter processing (enzymatic hydrolysis, prokaryotic production and oxidation) and the role played by the prokaryotic community in this context. During the MEDBIO multidisciplinary cruise performed in July 2005, the distribution of prokaryotic abundance and activities (exo enzymatic activity, heterotrophic production and respiratory activity) was studied. The results showed the presence of high exo enzymatic activity rates (mostly leucine amino peptidase) in the deep sea, while heterotrophic production and respiratory activity rates were high at surface. Some speculations on the different behaviors of the Carbon fluxes occurring among the different epi, meso and bathypelagic layers are reported. At the epipelagic layer both the decomposition and biomass production processes were high. At the mesopelagic layer the organic matter was quickly mobilised but not efficiently incorporated into biomass, therefore the dissolved monomers remained available in the water column for export to other trophic levels or utilization in other chemical processes (lateral advection, oxidation). The bathypelagic layer was characterised by high levels of hydrolytic activity coupled with relatively high prokaryotic production; in this layer, exo enzymatic activity levels fall in an order of magnitude similar to that observed at the epipelagic one. This finding highlights the importance of microbially mediated processes in sustaining life in the marine depths.

Callus induction, somatic embryogenesis and plant regeneration were obtained in lemon [Citrus limon (L.) Burm. cv `Femminello'] and sweet orange [C. sinensis (L.) Osb. cv `Washington Navel GS'] from cultures of stigma and style transverse thin cell layer explants [(t)TCLs]. Explants were cultured on 16 different media, based on the nutrients and vitamins of Murashige and Tucker medium (MT) supplemented with different combinations of 2,4-dichlorophenoxyacetic acid (2,4-D) and N-(2-chloro-4-pyridyl)-Nprime-phenylurea (4-CPPU). Sucrose (146 mM) was used as the sole carbon source. Somatic embryos arose from callus at the surface of stigma and style (t)TCLs 3–5 months after culture initiation of both sweet orange and lemon. The percentages of embryo formation from style (t)TCLs ranged from 0% (the media containing 2,4-D) to 16.0% (the medium supplemented with 4 mgrM 4-CPPU) for C. limon. Better results were obtained when stigma (t)TCLs from C. limon were used; in fact, percentages ranged from 0% on the media containing 2,4-D, with the only exception for the medium supplemented with 0.4 mgrM 2,4-D, to 24.8% on medium with 4 mgrM 4-CPPU. The embryogenic response of lemon (t)TCLs was usually higher than for sweet orange (t)TCLs. After about 3 months, somatic embryos developed into plantlets at high frequencies ranging from 53% to 75% for sweet orange and lemon style derived embryos, respectively.

Five clones of sour orange (Citrus aurantium L.) showing significant morphological differences were selected from our germplasm collection and characterized both by genetic and leaf volatiles analysis. The genetic studies were undertaken by the use of molecular markers developed by PCR-based techniques (ISSR and RAPD), while the leaf essential oil patterns were obtained by chromatographic and mass spectrometric determination. Data obtained suggest that reasonably similar information can be achieved from the two techniques, supporting each other in characterization studies.

We introduce a model of quantum teleportation on a channel built on a quantum dot chain. Quantum dots are coupled through hopping and each dot can accept zero, one or two electrons. Vacuum and double occupation states have the same potential energy, while single occupation states are characterized by a lower potential energy. A single dot initially decoupled from the others is weakly coupled with an external element (Bob), where a pair of electrons has been previously localized. Because of hopping after a suitable time the two dots charge states become maximally entangled. Another chain dot (Alice) is put in an unknown superposition of vacuum and double occupation states, and the other dots are initially empty. The time evolution of the system involves an electron diffusive process. A post selection procedure represented by the detection of charge pairs in a region of the chain equidistant from Alice and Bob, allows, if successful, the reconstruction on the Bob site of the unknown state initially encoded by Alice. The peculiar feature of the model is that the introduction of a trapped magnetic field strongly improves the process efficiency.

A study of the digestive enzymes of European eel was carried out in order to achieve information the digestive physiology of this species: total proteases, pepsin, trypsin, chymotrypsin, carboxypeptidases A and B, amylase and lipase were measured. After feeding, all enzyme patterns increased, particularly carboxypeptidase A and lipase in the intestine and stomach, respectively. The low levels of amylase activity measured in A. anguilla indicated the scarce hydrolytic activity over carbohydrates.

A cryopreservation procedure by dehydration and direct immersion in liquid nitrogen was developed for seeds of four polyembryonic Citrus species, and the sexual or nucellar origin of the recovered seedlings was investigated. Seeds of three species could be desiccated in a sterile air flow to 16% (C. sinensis) or 10% (C. aurantium and C. limon) moisture content with a negligible reduction in germination levels. Differently, the germinability of C. deliciosa seeds dropped to 50% after drying to 15% moisture content. Following dehydration treatments, a reduction in the average number of seedlings per germinated seed was always observed. However, all four species benefited from desiccation in terms of protection during immersion in liquid nitrogen, with C. sinensis and C. aurantium showing the greatest survival (93% germination) after cryopreservation. The Inter-Simple Sequence Repeat analysis of seedlings recovered from cryopreserved seeds showed that the dehydration/cryopreservation procedure promotes the germination of zygotic embryos and reduces the number of apomictic seedlings per seed.

We show that an high temperature expansion at fixed order parameter can be derived for the quantum Ising model. The basic point is to consider a statistical generating functional associated to the local spin state. The probability at thermal equilibrium of this state reflects directly the occurrence of a spontaneous symmetry breaking. It is possible to recover the expansion around the mean field in the system dimensionality if the ``direction'' in the Hilbert space of local spin states is suitably chosen. Results for the free energy at the critical temperature, as a function of the transverse field, in first order approximation in the inverse system dimensionality are compared with those of the standard approach., 10 Pages + 2 Figs. Submitted to Prl

Callus induction, somatic embryogenesis and plant regeneration were obtained in lemon [Citrus limon (L.) Burm. cv 'Femminello'] and sweet orange [C. sinensis (L.) Osb. cv `Washington Navel GS'] from cultures of stigma and style transverse thin cell layer explants [(t)TCLs]. Explants were cultured on 16 different media, based on the nutrients and vitamins of Murashige and Tucker medium (MT) supplemented with different combinations of 2,4-dichlorophenoxyacetic acid (2,4-D) and N-(2-chloro-4-pyridyl)-N'-phenylurea (4-CPPU). Sucrose (146 mM) was used as the sole carbon source. Somatic embryos arose from callus at the surface of stigma and style (t)TCLs 3-5 months after culture initiation of both sweet orange and lemon. The percentages of embryo formation from style (t)TCLs ranged from 0% (the media containing 2,4-D) to 16.0% (the medium supplemented with 4 muM 4-CPPU) for C. limon. Better results were obtained when stigma (t)TCLs from C. limon were used; in fact, percentages ranged from 0% on the media containing 2,4-D, with the only exception for the medium supplemented with 0.4 muM 2,4-D, to 24.8% on medium with 4 muM 4-CPPU. The embryogenic response of lemon (t)TCLs was usually higher than for sweet orange (t)TCLs. After about 3 months, somatic embryos developed into plantlets at high frequencies ranging from 53% to 75% for sweet orange and lemon style derived embryos, respectively.

Carotid surgery must be preventive; therefore cerebral protection procedures have been the centre of interest for a decade. Nowadays local cervical block anaesthesia seems to have changed the terms of the problem allowing achieve the aim of "no risk surgery". Therefore we considered our 16 year experience (352 carotids operated on 290 patients). Since 1990 we employed cervical block anaesthesia. In order to ratify as much as possible the two groups of comparison, considering that we adopted some exclusion criteria, we compared the results of the first hundred carotids that underwent surgery with general anaesthesia and the first hundred operated using cervical block anaesthesia. Since we adopted cervical block anaesthesia there was no need of intra-operative monitoring systems because we considered exclusively the patients' clinical answer to preclamping. The use of shunt decreased from 9% to 3%. Surgery performed in cervical block anaesthesia gives a positive impression. This is due to the fact that there is not only a significant reduction of the morbidity rate, especially from a neurologic point of view, but also a reduction of the post-operation hospital stay. Furthermore there is also a better organization of the surgical phases. Direct monitoring of the cerebral function allows a precise analysis of the peri-operatory neurological events. In conclusion our study suggests that cervical block anaesthesia allows clinical benefits for the patient as far as safety is concerned being also more convenient under the economic point of view.

We show that quantum computation can be performed in a system at thermal equilibrium if a spontaneous symmetry breaking occurs. The computing process is associated to the time evolution of the statistical average of the qubit coherence operator. This average defines logical states which evolve under the action of impulsive gate perturbations. Non trivial quantum coherence properties appear in the ordered phase characterized by a spontaneous symmetry breaking. Qubits are associated to spins and interaction with the lattice vibrations is approximated by an effective spin-spin interaction. A finite decoherence time is obtained only if spin correlations are taken into account in the framework of the Ising model as corrections to the Mean Field approximation. Decoherence is slowed down as the order parameter saturates., 9 pages, 0 figures

Conservation of citrus genetic resources needs an integrated in situ and e x situ approach. In view of preventing dissemination of diseases, it is necessary to resort to ex situ conservation for maintenance of clean material, whereas reinfection may be avoided by using in vivo and in vitro conservation. Following specific guidelines, the collection field fulfilling specific requirements or the insect-proof screenhouse can ensure in vivo conservation of a healthy gene pool as well as pomological traits. For several species, in vitro culture may play a major role as a conservation strategy or even be the only option available. Despite their several advantages, in vitro techniques still display considerable constraints such as genetic instability and length of tissue storage.

Somatic embryogenesis was used to eliminate Citrus psorosis virus (CPsV) from three citrus species (common mandarin, sweet orange and Dweet tangor), all of which regenerated somatic embryos with different embryogenic potential from stigma and style explants. CPsV was detected by double antibody sandwich-indirect-enzyme-linked immunosorbent assay (DASI-ELISA) in explants and embryogenic callus, but was not detested in any of the. plants obtained from somatic embryos, even 24 months after regeneration. Loss of juvenile characters (disappearance of thorns) was observed in the first year of growth and was retained in plants propagated by grafting from thornless stems. Somatic embryogenesis appears to be a very promising technique for the production of healthy citrus stocks.

We consider a model of bosons on a regular lattice with a kinetic energy due to hopping among sites and a potential energy due to strong on site interaction. A superfluid phase is expected when the ground state of the local energy is doubly degenerate. We consider a new scheme of simmetry breaking associated to the superfluid phase in which the order parameter is the statistical average of the quantum coherence operator associated to the superposition of the degenerate local ground states. In the strong coupling limit a systematic expansion of the free energy can be performed in terms of the hopping amplitude at constant order parameter. Within such an expansion we obtain a self-consistent equation for the order parameter. The first order approximation gives, in the case of degeneracy between single occupied and empty state, the same result of the standard mean field approximation for the ``hard core bosons''. This new approach to the superfluid phase is shown to have a natural application to the implementation of quantum computation on a superfluid., Comment: 8 pages

A new method for rearing the citrus flower moth (Prays citri Mill.) (Lepidoptera, Yponomeutidae) on lemon [Citrus limon (L.) Burm.] callus is reported. In the present research callus (an undifferentiated mass of plant cells that can be grown under sterile conditions on an artificial medium in vitro) was induced from lemon stigma and style explants cultured on Murashige and Skoog (MS) medium supplemented with 500 mg l(-1) malt extract, 13.3 mu M 6-benzylaminopurine, and 146 mM sucrose. Also somatic embryogenesis and plant regeneration were obtained from the cultures of styles and stigmas of lemon. Adults were obtained from larvae on infested flowers collected in the field. Different oviposition substrates were used: white oval pearls (WOP), black oval pearls (BOP), rooted shoots (RS) of lemon obtained in vitro, and artificial flowers containing lemon callus (AF). Larvae were reared on lemon callus. Adults oviposited on RS, on WOP, and on AF. BOP were rejected as oviposition substrates. The flower moth reared on callus oviposited fertile eggs. In our tests P. citri completed three generations on callus or on callus plus shoots. In the latter case the larvae preferred callus and fed on shoots only after callus was completely eaten. The life cycle on callus at 23 +/- 1 degrees C lasted about 21 days. There were significant differences between oviposition substrates for what concerns the number of eggs laid. It was observed that females generally preferred WOP (about 25 eggs/female) to AF (about 20 eggs/female) or RS (about 12 eggs/female) as oviposition substrate. Nevertheless the percentage of eggs that developed into adults was higher when AF sealed with stretched Parafilm were used (about 70% of eggs developed into adults). The method of rearing P. citri with AF was labour-saving and the feeding substrate (callus) had less tendency to become mouldy or decompose than when WOP and RS were used. Since such a diet is available for the insect all year round and callus can be produced in unlimited quantity, it could be possible to obtain a mass production of this moth.

Minigrafting was used for rescue of tissue culture regenerants of the following four species of Citrus: sour orange (C, aurantium L, 'AA CNR 31'), sweet orange [C, sinensis (L,) Osb, 'Valencia Late'],lemon [C, lemon (L,) Burm, 'Femminello Comune'] and mandarin (C, deliciosa Tenore 'Tardivo di Ciaculli'), The grafting was carried out with different scion types including shoots, roots, inverted roots and somatic embryos, This material was obtained in vitro from embryogenic style-derived callus, Seedlings of open-pollinated sour orange (C, aurantium L,), Cleopatra mandarin (C, reshni Hort, ex Tan.) and 'Troyer' citrange [C, sinensis Osb. x Poncirus trifoliata (L,) Raf.] were used as rootstocks, Minigrafting of shoots, roots, inverted roots and embryos regenerated in vitro allowed successful rescue of these four species. Percentages of successful minigrafts ranged from 100 % (shoots) to 2.5 % (inverted roots). The probability of successful graft unions Increased with the age of the rootstock, The final mean canopy leaf area (120 days after grafting) ranged from 5.2 cm(2) ('Tardivo di Ciaculli' mandarin grafted on 6 month old Cleopatra mandarin) to 157.9 cm(2) ('Valencia Late' sweet orange grafted on 18-month-old Cleopatra mandarin). In this work we examined some of the variables which influenced minigrafting and we determined the efficacy of this method for rescue of in vitro regenerants of Citrus. This method is also suggested as a technique to produce a high percentage of viable plants from in vitro regenerants difficult to root.

Somatic embryogenesis was induced and plant regeneration was obtained in 11 different genotypes of sweet orange navel group [Citrus sinensis (L.) Osb.] from cultures of stigma/style explants and underdeveloped ovules. Explants were cultured on 3 different modifications of Murashige and Skoog medium: 500 mg 1(-1) malt extract; 500 mg 1(-1) malt extract and 4.6 mu M kinetin; and 500 mg 1(-1) malt extract and 13.3 mu M 6-benzylaminopurine. Sucrose (146 mM) was used as carbon source. Somatic embryogenesis occurred 1-3 months after culture initiation from undeveloped ovule and stigma/style cultures of all the genotypes tested. Somatic embryos developed into plantlets with a high frequency (74%) after transfer to Murashige and Skoog medium supplemented with 146 mM sucrose and 500 mg 1(-1) malt extract. Plants were successfully transferred to soil.