921 resultados para NULL DIVERTOR TOKAMAKS


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This article is concerned with the risks associated with the monopolisation of information that is available from a single source only. Although there is a longstanding consensus that sole-source databases should not receive protection under the EU Database Directive, and there are legislative provisions to ensure that lawful users have access to a database’s contents, Ryanair v PR Aviation challenges this assumption by affirming that the use of non-protected databases can be restricted by contract. Owners of non-protected databases can contractually exclude lawful users from taking the benefit of statutorily permitted uses, because such databases are not covered from the legislation that declares this kind of contract null and void. We argue that this judgment is not consistent with the legislative history and can have a profound impact on the functioning of the digital single market, where new information services, such as meta-search engines or price-comparison websites, base their operation on the systematic extraction and re-utilisation of materials available from online sources. This is an issue that the Commission should address in a forthcoming evaluation of the Database Directive.

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Several studies of different bilingual groups including L2 learners, child bilinguals, heritage speakers and L1 attriters reveal similar performance on syntax-discourse interface properties such as anaphora resolution (Sorace, 2011 and references therein). Specifically, bilinguals seem to allow more optionality in the interpretation of overt subject pronouns in null subject languages, such as Greek, Italian and Spanish while the interpretation of null subject pronouns is indistinguishable from monolingual natives. Nevertheless, there is some evidence pointing to bilingualism effects on the interpretation of null subject pronouns too in heritage speakers’ grammars (Montrul, 2004) due to some form of ‘arrested’ development in this group of bilinguals. The present study seeks to investigate similarities and differences between two Greek–Swedish bilingual groups, heritage speakers and L1 attriters, in anaphora resolution of null and overt subject pronouns in Greek using a self-paced listening with a sentence-picture matching decision task at the end of each sentence. The two groups differ in crucial ways: heritage speakers were simultaneous or early bilinguals while the L1 attriters were adult learners of the second language, Swedish. Our findings reveal differences from monolingual preferences in the interpretation of the overt pronoun for both heritage and attrited speakers while the differences attested between the two groups in the interpretation of null subject pronouns affect only response times with heritage being faster than attrited speakers. We argue that our results do not support an age of onset or differential input effects on bilingual performance in pronoun resolution.

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Sorace (2000, 2005) has claimed that while L2 learners can easily acquire properties of L2 narrow syntax they have significant difficulty with regard to interpretation and the discourse distribution of related properties, resulting in so-called residual optionality. However, there is no consensus as to what this difficulty indicates. Is it related to an insurmountable grammatical representational deficit (in the sense of representation deficit approaches; e.g. Beck 1998, Franceschina 2001, Hawkins 2005), is it due to cross-linguistic interference, or is it just a delay due to a greater complexity involved in the acquisition of interface-conditioned properties? In this article, I explore the L2 distribution of null and overt subject pronouns of English speaking learners of L2 Spanish. While intermediate learners clearly have knowledge of the syntax of Spanish null subjects, they do not have target-like pragmatic knowledge of their distribution with overt subjects. The present data demonstrate, however, that this difficulty is overcome at highly advanced stages of L2 development, thus suggesting that properties at the syntax-pragmatics interface are not destined for inevitable fossilization.

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The purpose of this article is two-fold. First, via a critical review of available studies on the adult L2 resetting of the Null-Subject Parameter (NSP) and in light of a typologically wide sampling of languages, we conclude that the NSP cluster is much narrower in scope than is reflected in the design and discussion of most L2 studies. Secondly, we present original research on the L2 resetting of the NSP by two groups of adult English intermediate learners of L2 Spanish: a study-abroad group and a class-room only group. We seek to quantify the extent to which study-abroad experience, that is, increased exposure to native input, is beneficial specifically as it relates to the acquisition of new functional features needed for parameter re-setting (cf. Isabelli 2004). Despite the observable and clandestine linguistic benefits to study-abroad, our data suggest that for the resetting of the NSP, at least, such exposure to native input is not particularly gainful.

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Taking a generative perspective, we divide aspects of language into three broad categories: those that cannot be learned (are inherent in Universal Grammar), those that are derived from Universal Grammar, and those that must be learned from the input. Using this framework of language to clarify the “what” of learning, we take the acquisition of null (and overt) subjects in languages like Spanish as an example of how to apply the framework. We demonstrate what properties of a null-subject grammar cannot be learned explicitly, which properties can, but also argue that it is an open empirical question as to whether these latter properties are learned using explicit processes, showing how linguistic and psychological approaches may intersect to better understand acquisition.

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Contemporary research in generative second language (L2) acquisition has attempted to address observable target-deviant aspects of L2 grammars within a UG-continuity framework (e.g. Lardiere 2000; Schwartz 2003; Sprouse 2004; Prévost & White 1999, 2000). With the aforementioned in mind, the independence of pragmatic and syntactic development, independently observed elsewhere (e.g. Grodzinsky & Reinhart 1993; Lust et al. 1986; Pacheco & Flynn 2005; Serratrice, Sorace & Paoli 2004), becomes particularly interesting. In what follows, I examine the resetting of the Null-Subject Parameter (NSP) for English learners of L2 Spanish. I argue that insensitivity to associated discoursepragmatic constraints on the discursive distribution of overt/null subjects accounts for what appear to be particular errors as a result of syntactic deficits. It is demonstrated that despite target-deviant performance, the majority must have native-like syntactic competence given their knowledge of the Overt Pronoun Constraint (Montalbetti 1984), a principle associated with the Spanish-type setting of the NSP.

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Fucoidan, a sulfated polysaccharide from Fucus vesiculosus, decreases bleeding time and clotting time in hemophilia, possibly through inhibition of tissue factor pathway inhibitor. However, its effect on platelets and the receptor by which fucoidan induces cellular processes has not been elucidated. In this study, we demonstrate that fucoidan induces platelet activation in a concentration-dependent manner. Fucoidan-induced platelet activation was completely abolished by the pan-Src family kinase (SFK) inhibitor, PP2, or when Syk is inhibited. PP2 abolished phosphorylations of Syk and Phospholipase C-γ2. Fucoidan-induced platelet activation had a lag phase, which is reminiscent of platelet activation by collagen and CLEC-2 receptor agonists. Platelet activation by fucoidan was only slightly inhibited in FcRγ-chain null mice, indicating that fucoidan was not acting primarily through GPVI receptor. On the other hand, fucoidan-induced platelet activation was inhibited in platelet-specific CLEC-2 knock-out murine platelets revealing CLEC-2 as a physiological target of fucoidan. Thus, our data show fucoidan as a novel CLEC-2 receptor agonist that activates platelets through a SFK-dependent signaling pathway. Furthermore, the efficacy of fucoidan in hemophilia raises the possibility that decreased bleeding times could be achieved through activation of platelets.

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Filamin A (FlnA) cross-links actin filaments and connects the Von Willebrand factor receptor GPIb-IX-V to the underlying cytoskeleton in platelets. Because FlnA deficiency is embryonic lethal, mice lacking FlnA in platelets were generated by breeding FlnA(loxP/loxP) females with GATA1-Cre males. FlnA(loxP/y) GATA1-Cre males have a macrothrombocytopenia and increased tail bleeding times. FlnA-null platelets have decreased expression and altered surface distribution of GPIbalpha because they lack the normal cytoskeletal linkage of GPIbalpha to underlying actin filaments. This results in approximately 70% less platelet coverage on collagen-coated surfaces at shear rates of 1,500/s, compared with wild-type platelets. Unexpectedly, however, immunoreceptor tyrosine-based activation motif (ITAM)- and ITAM-like-mediated signals are severely compromised in FlnA-null platelets. FlnA-null platelets fail to spread and have decreased alpha-granule secretion, integrin alphaIIbbeta3 activation, and protein tyrosine phosphorylation, particularly that of the protein tyrosine kinase Syk and phospholipase C-gamma2, in response to stimulation through the collagen receptor GPVI and the C-type lectin-like receptor 2. This signaling defect was traced to the loss of a novel FlnA-Syk interaction, as Syk binds to FlnA at immunoglobulin-like repeat 5. Our findings reveal that the interaction between FlnA and Syk regulates ITAM- and ITAM-like-containing receptor signaling and platelet function.

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Actin polymerization drives multiple cell processes involving movement and shape change. SCAR/WAVE proteins connect signaling to actin polymerization through the activation of the Arp2/3 complex. SCAR/WAVE is normally found in a complex with four other proteins: PIR121, Nap1, Abi2,and HSPC300 (Figure S1A available online) [1-3]. However,there is no consensus as to whether the complex functions as an unchanging unit or if it alters its composition in response to stimulation, as originally proposed by Edenet al. [1]. It also is unclear whether complex members exclusively regulate SCAR/WAVEs or if they have additional targets [4-6]. Here, we analyze the roles of the unique Dictyostelium Abi. We find that abiA null mutants show less severe defects in motility than do scar null cells, indicating--unexpectedly--that SCAR retains partial activity in the absence of Abi. Furthermore, abiA null mutants have a serious defect in cytokinesis, which is not seen in other SCAR complex mutants and is seen only when SCAR itself is present. Detailed examination reveals that normal cytokinesis requires SCAR activity, apparently regulated through multiple pathways.

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A large body of psycholinguistic research has revealed that during sentence interpretation adults coordinate multiple sources of information. Particularly, they draw both on linguistic properties of the message and on information from the context to constrain their interpretations. Relatively little however is known about how this integrative processor develops through language acquisition and about how children process language. In this study, two on-line picture verification tasks were used to examine how 1st, 2nd and 4th/5th grade monolingual Greek children resolve pronoun ambiguities during sentence interpretation and how their performance compares to that of adults on the same tasks. Specifically, we manipulated the type of subject pronoun, i.e. null or overt, and examined how this affected participants’ preferences for competing antecedents, i.e. in the subject or object position. The results revealed both similarities and differences in how adults and the various child groups comprehended ambiguous pronominal forms. Particularly, although adults and children alike showed sensitivity to the distribution of overt and null subject pronouns, this did not always lead to convergent interpretation preferences.

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The transcription factor REST is a key suppressor of neuronal genes in non-neuronal tissues. REST has been shown to suppress pro-neuronal microRNAs in neural progenitors indicating that REST-mediated neurogenic suppression may act in part via microRNAs. We used neural differentiation of Rest-null mouse ESC to identify dozens of microRNAs regulated by REST during neural development. One of the identified microRNAs, miR-375, was upregulated during human spinal motor neuron development. We found that miR-375 facilitates spinal motor neurogenesis by targeting the cyclin kinase CCND2 and the transcription factor PAX6. Additionally, miR-375 inhibits the tumor suppressor p53 and protects neurons from apoptosis in response to DNA damage. Interestingly, motor neurons derived from a spinal muscular atrophy patient displayed depressed miR-375 expression and elevated p53 protein levels. Importantly, SMA motor neurons were significantly more susceptible to DNA damage induced apoptosis suggesting that miR-375 may play a protective role in motor neurons.

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A climatology is developed for tornadoes during 1980–2012 in the British Isles, defined in this article as England, Scotland, Wales, Northern Ireland, Republic of Ireland, Channel Islands, and the Isle of Man. The climatology includes parent storm type, interannual variability, annual and diurnal cycles, intensities, oc- currence of outbreaks (defined as three or more tornadoes in the same day), geographic distribution, and environmental conditions derived from proximity soundings of tornadoes. Tornado reports are from the Tornado and Storm Research Organization (TORRO). Over the 33 years, there were a mean of 34.3 tor- nadoes and 19.5 tornado days (number of days in which at least one tornado occurred) annually. Tornadoes and tornado outbreaks were most commonly produced from linear storms, defined as radar signatures at least 75 km long and approximately 3 times as long as wide. Most (78%) tornadoes occurred in England. The probability of a tornado within 10 km of a point was highest in the south, southeast, and west of England. On average, there were 2.5 tornado outbreaks every year. Where intensity was known, 95% of tornadoes were classified as F0 or F1 with the remainder classified as F2. There were no tornadoes rated F3 or greater during this time period. Tornadoes occurred throughout the year with a maximum from May through October. Finally, tornadoes tended to occur in low-CAPE, high-shear environments. Tornadoes in the British Isles were difficult to predict using only sounding-derived parameters because there were no clear thresholds between null, tornadic, outbreak, and significant tornado cases.

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We introduce empirical work on Romance language acquisition with respect to the interfaces of syntax with other modules of grammar (internal interfaces) and other domains of cognition (external interfaces). We do so by choosing specific phenomena within the following interfaces: syntax-morphology, syntax-semantics and syn-tax-pragmatics. In the domain of syntax-morphology we focus on grammatical gender, with respect to the syntax-semantics interface we focus on adjectival placement (pre- and post-nominal) and with regard to the syntax-discourse/pragmatics interface we review work on the null/overt subject distribution. Finally, we summarize research on articles, suggesting that articles represent a multiple interface. We provide examples from different types of learners and across the four major Romance languages French, Italian, Portuguese and Spanish. While our central goal is to summarize and generalize across major findings, we will also point to potential problems concerning the interface approach, e.g. the association of particular phenomena with a specific interface and the assumption that internal interfaces are less problematic than external ones.

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• Premise of the study: Microsatellite markers were developed using hoop-petticoat daffodils ( Narcissus sect. Bulbocodii ; Amaryllidaceae) to aid in the taxonomic revision of the section, and further to evaluate their broad applicability for daffodil cultivar identification. • Methods and Results: Three hundred fifty-one primer pairs were developed using a commercial service. Nineteen polymorphic and repeatable markers were developed by screening 67 of these primer pairs. Of these, 11 chosen markers were used to screen 317 samples; the number of alleles per locus ranged from four to 21, and the observed heterozygosity ranged from 0.101 to 0.297. There were null genotypes in some samples for six of the markers. All the microsatellites were transferable to other Narcissus sections. • Conclusions: The results indicate that these new markers have sufficient potential variation to be used for taxonomic revision of the genus and to distinguish many commercial daffodil cultivars.

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Nitric oxide synthase (NOS) has been reported to be involved with both bone healing and bone metabolism. The aim of this study was to test the null hypothesis that there is no correlation between new bone formation during mandibular distraction osteogenesis and NOS expression in the trigeminal ganglion of rats. Newly formed tissue during distraction osteogenesis and trigeminal NOS expression measured by the NADPH-diaphorase (NADPH-d) reaction were evaluated in 72 male Wistar rats by histomorphometric and histochemical methods. In animals submitted to 0.5 mm/day distraction osteogenesis, the percentage of bone tissue was higher in the basal area of the mandibles compared with the center and significantly increased through the experimental periods (P < 0.05). At the sixth postoperative week, the difference in bone formation between the continuous and acute distraction osteogenesis groups was the highest. Significant correlation between new bone formation by distraction osteogenesis and NADPH-d-reactive neurons was found, varying according to neuronal cell size (r = -0.6, P = 0.005, small cells strongly stained; r = 0.5, P = 0.018, large cells moderately stained). The results suggest that NOS may play a role in the bone healing process via neurogenic pathways, and the phenomenon seems to be neuronal cell morphotype-dependent. Further studies are now warranted to investigate the mechanistic link between the expression of trigeminal NOS and mandibular new bone formation by distraction osteogenesis.