Nonlocality is transitive

We show a transitivity property of nonlocal correlations: There exist tripartite nonsignaling correlations of which the bipartite marginals between A and B as well as B and C are nonlocal and any tripartite nonsignaling system between A, B, and C consistent with them must be such that the bipartite marginal between A and C is also nonlocal. This property represents a step towards ruling out certain alternative models for the explanation of quantum correlations such as hidden communication at finite speed. Whereas it is not possible to rule out this model experimentally, it is the goal of our approach to demonstrate this explanation to be logically inconsistent: either the communication cannot remain hidden, or its speed has to be infinite. The existence of a three-party system that is pairwise nonlocal is of independent interest in the light of the monogamy property of nonlocality.Comment: 4 pages, 2 figures, v2: published versio

Segmental identity and cerebellar granule cell induction in rhombomere 1

BACKGROUND: Cerebellar granule cell precursors are specifically generated within the hindbrain segment, rhombomere 1, which is bounded rostrally by the midbrain/hindbrain isthmus and caudally by the boundary of the Hoxa2 expression domain. While graded signals from the isthmus have a demonstrable patterning role within this region, the significance of segmental identity for neuronal specification within rhombomere 1 is unexplored. We examined the response of granule cell precursors to the overexpression of Hoxa2, which normally determines patterns of development specific to the hindbrain. How much does the development of the cerebellum, a midbrain/hindbrain structure, reflect its neuromeric origin as a hindbrain segment? RESULTS: We show that a Gbx2-positive, Otx2-/Hoxa2-negative territory corresponding to rhombomere 1 forms prior to an identifiable isthmic organiser. Early global overexpression of Hoxa2 at embryonic day 0 has no effect on the expression of isthmic signalling molecules or the allocation of rhombomere 1 territory, but selectively results in the loss of granule cell markers at embryonic day 6 and the depletion of cell bodies from the external granule cell layer. By comparison the trochlear nucleus and locus coeruleus form normally in ventral rhombomere 1 under these conditions. Microsurgery, coupled with electroporation, to target Hoxa2 overexpression to rhombic lip precursors, reveals a profound, autonomous respecification of migration. Rhombic lip derivatives, normally destined to occupy the external granule cell layer, violate the cerebellar boundary to form a ventrolateral nucleus in a position comparable to that occupied by rhombic lip derived neurons in rhombomere 2. CONCLUSIONS: Different overexpression strategies reveal that the recognition of migration cues by granule cell precursors is dependent on their identity as rhombomere 1 derivatives. Segmental patterning cues operate autonomously within the rhombic lip precursor pool. By contrast, a subset of coextensive nuclei is refractory to ectopic Hoxa2 and is presumably induced solely by isthmic organiser activity. Thus, graded (isthmic) and segmental mechanisms may operate exclusively of one another in the specification of different neuronal populations within rhombomere 1. The early designation of an Otx2-negative, Hoxa2-negative region, prior to the appearance of the isthmic organiser, is a key initial step in the specification of the cerebellum

Effects of dietary polyunsaturated fatty acid/vitamin E (PUFA/tocopherol) ratio on antioxidant defence mechanisms of juvenile gilthead sea bream (Sparus aurata L., Osteichthyes, Sparidae)

Lipid peroxidation, specifically polyunsaturated fatty acid (PUFA) oxidation is highly deleterious, resulting in damage to cellular biomembranes, and may be a principal cause of several diseases in fish including jaundice and nutritional muscular dystrophy. Tissue lipid PUFA content and composition are critical factors in lipid peroxidation, as is the level of endogenous antioxidant molecules such as vitamin E. The primary objective of the present study was the characterization of antioxidant systems in a cultured juvenile marine fish, gilthead sea bream (Sparus aurata) with the underlying aim to understand how to avoid oxidation problems that may cause pathologies and disease and so to enhance growth and quality of early ongrowing stages. Juvenile sea bream were fed diets having either high or low levels of fish oil and supplemented or basal levels of vitamin E with PUFA/vitamin E ratios ranging from 117 ± 12 in the diet with low PUFA supplemented with vitamin E to 745 ± 48 in the diet with high PUFA with no additional vitamin E. None of the diets had serious deliterious effects on growth or survival of the fish, but the different dietary regimes were effective in significantly altering the PUFA/vitamin E ratios in the fish livers with values ranging from 5.7 ± 0.4 in fish fed the diet with low PUFA supplemented with vitamin E to 91.1 ± 13.2 in fish fed the diet with high PUFA with no additional vitamin E. This had effects on the peroxidation status of the fish as indicated by the significantly altered levels of in vivo lipid peroxidation products measured in liver, with fish fed the diet rich in PUFA and low in vitamin E showing significantly higher values of thiobarbituric acid reactive substances (TBARS) and isoprostanes. The isoprostane levels generally followed the same pattern as the TBARS levels supporting its value as an indicator of in vivo oxidative stress in fish, as it is in mammals. However, few significant effects on antioxidant enzyme activities were observed suggesting that more severe conditions may be required to affect these activities such as increasing the PUFA/vitamin E ratio or by increasing peroxidative stress through the feeding of oxidized oils

Increased activities of hepatic antioxidant defence enzymes in juvenile gilthead sea bream (Sparus aurata L.) fed dietary oxidised oil: attenuation by dietary vitamin E

Previously, we had shown that altering the highly unsaturated fatty acid (HUFA)/vitamin E ratios in gilthead sea bream livers significantly affected their peroxidation status, with fish fed a diet rich in HUFA and low in vitamin E showing significantly higher values of lipid peroxidation products, without, however, significant effects on liver antioxidant defence enzyme activities. The aim of the present trial was to further characterise the biochemical indicators of peroxidative stress in juvenile gilthead sea bream. A high pro-oxidative stress was induced by feeding diets containing around 7% of the dry weight as n 3 HUFA. The potential peroxidative stress was increased by oxidising the oil, increasing the peroxide value of the oil some 10-fold. These oils were fed without or with supplemental vitamin E (a-tocopheryl acetate at 200 mg kg 1 dry diet) giving four diets in total. Fish were sampled after 30 and 60 days of feeding the experimental diets. None of the diets had any serious deleterious effects on growth and mortality of the fish during the trial. Similarly, there were few significant effects due to dietary oxidised oil or supplementary vitamin E on liver lipid and fatty acid profiles and, in particular, the proportions of HUFA were not decreased by dietary oxidised oil. The vitamin E content of the liver reflected the vitamin E content of the diets but was also affected by dietary oxidised oil being reduced by oxidised oil in fish fed diets without supplemental vitamin E but, unexpectedly, increased by oxidised oil in fish fed diets supplemented with vitamin E. Liver thiobarbituric acid reactive substances (TBARS) levels were significantly lower in fish fed diets supplemented with vitamin E whereas dietary oxidised oil had no major effect on lipid peroxidation products. Catalase (CAT) and superoxide dismutase (SOD) activities were both increased in fish fed dietary oxidised oil and reduced by supplementary vitamin E after 30 days feeding. In contrast, glutathione peroxidase (GPX) was less affected by the diets, and the activities of glutathione-Stransferase (GST) and glutathione reductase (GR) were only reduced by dietary vitamin E after 60 days of feeding. However, all the enzyme activities were significantly affected by the duration of feeding, but the number of interactions between the three factors (time, oil and vitamin E) showed that the relationships were complicated. In conclusion, the present study showed that feeding diets containing oxidised oil significantly affected the activities of liver antioxidant defence enzymes and that dietary vitamin E partially abrogated these effects. Growth and survival of the fish were relatively unaffected suggesting that the responses in gilthead sea bream offered effective protection. However, the duration of feeding the diets of high pro-oxidative stress was observed to have a hitherto unknown effect, possibly the result of an adaptive process, but which requires further investigation

Severe tetracycline dental discoloration : restoration with conventional feldspathic ceramic veneers. A clinical report

The treatment of severe tetracycline discoloration is a challenge for the dentist. There are several treatment options and one of the most effective is the use of feldspathic veneers. The aim of this clinical case was to carry out the replacement with conventional feldspathic ceramic veneers on a patient with highly stained teeth (grade IV tetracycline) by a minimally invasive approach. Clinical examination revealed gingival retraction, color change of the veneers, ceramic cracked of 1.1 and 1.3 and incisal wear in lower anterior teeth. The decision was to retreat with feldspathic ceramic veneers from 1.6 to 2.6. Premolars and first molars were included because its dark color intensifies the width buccal corridors. Also, the restoration with veneers from 3.3 to 4.3 was considered. Firstly, the veneers were removed and the color was selected by the Vitapan 3D Master guide (Vita Zahnfabrick, Bad Säckingen, Germany). Mock-up was made to evaluate aesthetic, phonetic and functional parameters. Then, teeth were prepared through the mock-up in order to reduce the minimal amount of dental tissue possible. Opaque dentine mass of microhybrid composite (Esthet-X A2O, Dentsply Sirona, Konstanz, Germany) was placed to mask the most intense stains. The definitive impressions were taken with silicone (Aquasil Ultra XLV, Dentsply Sirona, Konstanz, Germany) were taken to fabricate conventional feldsphatic ceramic veneers (Noritake kisai Co, Ltd. Japan) by the parallel stratification masking technique. For cementing, an opaque cement was selected from the try-in tests (Calibra, Dentsply Sirona, Konstanz, Germany) and the composite was silicatized with an air-abrasion device. A favorable and minimally invasive result was achieved to treat grade IV tetracycline stains, surpassing the patient?s aesthetic expectations and functional needs

Разработка архитектуры и программных средств витрин данных для предприятия нефтегазовой отрасли

Анализируются проблемы создания отраслевых информационно-аналитических систем, основанных на современных OLAP-технологиях. Рассмотрен вариант архитектуры хранилища данных для крупного нефтегазодобывающего предприятия на примере проектирования тематической витрины данных, включающего анализ специфической предметной области, проектирование многомерных структур данных, постановку аналитических задач и их решение

Millora genètica vegetal

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