907 resultados para Origin and destination.


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Here, we describe gene expression compositional assignment (GECA), a powerful, yet simple method based on compositional statistics that can validate the transfer of prior knowledge, such as gene lists, into independent data sets, platforms and technologies. Transcriptional profiling has been used to derive gene lists that stratify patients into prognostic molecular subgroups and assess biomarker performance in the pre-clinical setting. Archived public data sets are an invaluable resource for subsequent in silico validation, though their use can lead to data integration issues. We show that GECA can be used without the need for normalising expression levels between data sets and can outperform rank-based correlation methods. To validate GECA, we demonstrate its success in the cross-platform transfer of gene lists in different domains including: bladder cancer staging, tumour site of origin and mislabelled cell lines. We also show its effectiveness in transferring an epithelial ovarian cancer prognostic gene signature across technologies, from a microarray to a next-generation sequencing setting. In a final case study, we predict the tumour site of origin and histopathology of epithelial ovarian cancer cell lines. In particular, we identify and validate the commonly-used cell line OVCAR-5 as non-ovarian, being gastrointestinal in origin. GECA is available as an open-source R package.

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Background
First generation migrants are reportedly at higher risk of mental ill-health compared to the settled population. This paper systematically reviews and synthesizes all reviews on the mental health of first generation migrants in order to appraise the risk factors for, and explain differences in, the mental health of this population.
Methods
Scientific databases were searched for systematic reviews (inception-November 2015) which provided quantitative data on the mental ill-health of first generation migrants and associated risk factors. Two reviewers screened titles, abstracts and full text papers for their suitability against pre-specified criteria, methodological quality was assessed.
Results
One thousand eight hundred twenty articles were identified, eight met inclusion criteria, which were all moderate or low quality. Depression was mostly higher in first generation migrants in general, and in refugees/asylum seekers when analysed separately. However, for both groups there was wide variation in prevalence rates, from 5 to 44 % compared with prevalence rates of 8–12 % in the general population. Post-Traumatic Stress Disorder prevalence was higher for both first generation migrants in general and for refugees/asylum seekers compared with the settled majority. Post-Traumatic Stress Disorder prevalence in first generation migrants in general and refugees/ asylum seekers ranged from 9 to 36 % compared with reported prevalence rates of 1–2 % in the general population. Few studies presented anxiety prevalence rates in first generation migrants and there was wide variation in those that did. Prevalence ranged from 4 to 40 % compared with reported prevalence of 5 % in the general population. Two reviews assessed the psychotic disorder risk, reporting this was two to three times more likely in adult first generation migrants. However, one review on the risk of schizophrenia in refugees reported similar prevalence rates (2 %) to estimates of prevalence among the settled majority (3 %). Risk factors for mental ill-health included low Gross National Product in the host country, downward social mobility, country of origin, and host country.
Conclusion
First generation migrants may be at increased risk of mental illness and public health policy must account for this and influencing factors. High quality research in the area is urgently needed as is the use of culturally specific validated measurement tools for assessing migrant mental health.

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Les procédures appliquées avant l’abattage des animaux influencent directement la qualité de la viande en modulant l’état physiologique des porcs; ainsi, l’augmentation de la température corporelle, les taux élevés de lactate sanguin et l’épuisement des réserves de glycogène entre autres, occasionnent la majorité des baisses de qualité. L’objectif de cette thèse était de valider des outils indicateurs de stress porcin pour les fermes et les abattoirs. Ceux-ci seraient appliqués à la surveillance du bien-être animal et à la prédiction de variation de qualité de la viande porcine au niveau commercial. Premierement, les résultats de la thèse ont permis de conclure qu’un des outils développés (analyseur portatif de lactate) mesure la variation du niveau de lactate sanguin associé à l’état physiologique des porcs dans la phase péri-mortem et aide à expliquer la variation de la qualité de la viande chez le porc à l’abattoir, en particulier dans les muscles du jambon. Deuxièmement, les résultats des audits du bien-être animal appliqués de la ferme à l’abattoir ont démontré que la qualité du système d’élevage à la ferme d’origine et les compétences du chauffeur de camion sont d’importants critères affectant la réponse comportementale des porcs à la manipulation avant l’abattage. Ces résultats ont également démontré que les conditions de logement à la ferme (la faible densité et l’enrichissement dans les enclos), le comportement des porcs en période pré-abattage (glissade), ainsi que les interventions du manipulateur (utilisation du bâton électrique) dans la zone d’étourdissement de l’abattoir affectent négativement la variation de la qualité de la viande. L’application des protocoles d’audits dans la filière porcine a également démontré que le respect des critères de bien-être animal fixés par un outil de vérification est primordiale et permet de contrôler les conditions de bien-être des porcs à chaque étape de la période pré-abattage, de produire une viande de qualité supérieure et de réduire les pertes. Les audits de bien-être animal sont donc un outil qui apporte des resultats très pertinents pour aider a éviter les variations de la qualité de la viande chez le porc. Troisièmement, la thermographie infrarouge s’est avéré être une technique prometteuse permettant d’évaluer la variation de température corporelle de l’animal pendant et après un stress physique, en particulier lorsque cette mesure est prise derrière les oreilles. En conclusion, les outils validés à travers cette thèse représentent des méthodologies non invasives et potentiellement complémentaires à d’autres approches d’évaluation de l’état physiologique et du bien-être animal par rapport au stress, permettant de réduire les pertes de qualité de viande (par exemple en utilisation conjointe avec le niveau de lactate sanguin et les indicateurs de stress comportemental, entre autres).

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For in vitro differentiation of bone marrow-derived mesenchymal stem cells/mesenchymal stromal cells into osteoblasts by 2-dimensional cell culture a variety of protocols have been used and evaluated in the past. Especially the external phosphate source used to induce mineralization varies considerably both in respect to chemical composition and concentration. In light of the recent findings that inorganic phosphate directs gene expression of genes crucial for bone development, the need for a standardized phosphate source in in vitro differentiation becomes apparent. We show that chemical composition (inorganic versus organic phosphate origin) and concentration of phosphate supplementation exert a severe impact on the results of gene expression for the genes commonly used as markers for osteoblast formation as well as on the composition of the mineral formed. Specifically, the intensity of gene expression does not necessarily correlate with a high quality mineralized matrix. Our study demonstrates advantages of using inorganic phosphate instead of beta-glycerophosphate and propose colorimetric quantification methods for calcium and phosphate ions as cost-and time-effective alternatives to X-ray diffraction and Fourier-transform infrared spectroscopy for determination of the calcium phosphate ratio and concentration of mineral matrix formed under in vitro-conditions. We critically discuss the different assays used to assess in vitro bone formation in respect to specificity and provide a detailed in vitro protocol that could help to avoid contradictory results due to variances in experimental design.

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A actividade vitivinícola possui um conjunto diverso de características presentes no solo, território e comunidade que fazem parte do património cultural de uma determinada região. Quando a tradição se traduz num conceito como terroir que é formado por características territoriais, sociais e culturais de uma região rural, o vinho apresenta uma “assinatura” que se escreve “naturalmente” no paladar regionalmente identificado. Os vinhos da Região de Nemea, na Grécia e de Basto (Região dos Vinhos Verdes) em Portugal, estão ambos sob a proteção dos regulamentos das Denominações de Origem. No entanto, apesar de ambos serem regulados por sistemas institucionais de certificação e controlo de qualidade, afigura-se a necessidade de questionar se o património cultural e a identidade territorial específica, “impressa” em ambos os terroirs, pode ser protegida num sentido mais abrangente do que apenas origem e qualidade. Em Nemea, a discussão entre os produtores diz respeito ao estabelecimento de sub-zonas, isto é incluir na regulação PDO uma diferente categorização territorial com base no terroir. Ou seja, para além de estar presente no rótulo a designação PDO, as garrafas incluirão ainda informação certificada sobre a área específica (dentro do mesmo terroir) onde o vinho foi produzido. A acontecer resultaria em diferentes status de qualidade de acordo com as diferentes aldeias de Nemea onde as vinhas estão localizadas. O que teria possíveis impactos no valor das propriedades e no uso dos solos. Para além disso, a não participação da Cooperativa de Nemea na SON (a associação local de produtores de vinho) e como tal na discussão principal sobre as mudanças e os desafios sobre o terroir de Nemea constitui um problema no sector vitivinícola de Nemea. Em primeiro lugar estabelece uma relação de não-comunicação entre os dois mais importantes agentes desse sector – as companhias vinícolas e a Cooperativa. Em segundo lugar porque constituiu uma possibilidade real, não só para os viticultores ficarem arredados dessa discussão, como também (porque não representados pela cooperativa) ficar impossibilitado um consenso sobre as mudanças discutidas. Isto poderá criar um ‘clima’ de desconfiança levando a discussão para ‘arenas’ deslocalizadas e como tal para decisões ‘desterritorializadas’ Em Basto, há vários produtores que começaram a vender a sua produção para distribuidoras localizadas externamente à sub-região de Basto, mas dentro da Região dos Vinhos Verdes, uma vez que essas companhias tem um melhor estatuto nacional e internacional e uma melhor rede de exportações. Isto está ainda relacionado com uma competição por uma melhor rede de contactos e status mais forte, tornando as discussões sobre estratégias comuns para o desenvolvimento rural e regional de Basto mais difícil de acontecer (sobre isto a palavra impossível foi constantemente usada durante as entrevistas com os produtores de vinho). A relação predominante entre produtores é caracterizada por relações individualistas. Contudo foi observado que essas posições são ainda caracterizadas por uma desconfiança no interior da rede interprofissional local: conflitos para conseguir os mesmos potenciais clientes; comprar uvas a viticultores com melhor rácio qualidade/preço; estratégias individuais para conseguir um melhor status político na relação com a Comissão dos Vinhos Verdes. Para além disso a inexistência de uma activa intermediação institucional (autoridades municipais e a Comissão de Vinho Verde), a inexistência entre os produtores de Basto de uma associação ou mesmo a inexistência de uma cooperativa local tem levado a região de Basto a uma posição de subpromoção nas estratégias de promoção do Vinho Verde em comparação com outras sub-regiões. É também evidente pelos resultados que as mudanças no sector vitivinícolas na região de Basto têm sido estimuladas de fora da região (em resposta também às necessidades dos mercados internacionais) e raramente de dentro – mais uma vez, ‘arenas’ não localizadas e como tal decisões desterritorializadas. Nesse sentido, toda essa discussão e planeamento estratégico, terão um papel vital na preservação da identidade localizada do terroir perante os riscos de descaracterização e desterritorialização. Em suma, para ambos os casos, um dos maiores desafios parece ser como preservar o terroir vitivinícola e como tal o seu carácter e identidade local, quando a rede interprofissional em ambas as regiões se caracteriza, tanto por relações não-consensuais em Nemea como pelo modus operandi de isolamento sem comunicação em Basto. Como tal há uma necessidade de envolvimento entre os diversos agentes e as autoridades locais no sentido de uma rede localizada de governança. Assim sendo, em ambas as regiões, a existência dessa rede é essencial para prevenir os efeitos negativos na identidade do produto e na sua produção. Uma estratégia de planeamento integrado para o sector será vital para preservar essa identidade, prevenindo a sua desterritorialização através de uma restruturação do conhecimento tradicional em simultâneo com a democratização do acesso ao conhecimento das técnicas modernas de produção vitivinícola.

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Soft tissue sarcomas (STS) comprise a heterogenenous group of greater than 50 malignancies of putative mesenchymal cell origin and as such they may arise in diverse tissue types in various anatomical locations throughout the whole body. Collectively they account for approximately 1% of all human malignancies yet have a spectrum of aggressive behaviours amongst their subtypes. They thus pose a particular challenge to manage and remain an under investigated group of cancers with no generally applicable new therapies in the past 40 years and an overall 5-year survival rate that remains stagnant at around 50%. From September 2000 to July 2006 I undertook a full time post-doctoral level research fellowship at the MD Anderson Cancer Center, Houston, Texas, USA in the department of Surgical Oncology to investigate the biology of soft tissue sarcoma and test novel anti- sarcoma adenovirus-based therapy in the preclinical nude rat model of isolated limb perfusion against human sarcoma xenografts. This work, in collaboration with colleagues as indicated herein, led to a number of publications in the scientific literature furthering our understanding of the malignant phenotype of sarcoma and reported preclinical studies with wild-type p53, in a replication deficient adenovirus vector, and oncolytic adenoviruses administered by isolated limb perfusion. Additional collaborative and pioneering preclinical studies reported the molecular imaging of sarcoma response to systemically delivered therapeutic phage RGD-4c AAVP. Doxorubicin chemotherapy is the single most active broadly applicable anti-sarcoma chemotherapeutic yet only has an approximate 30% overall response rate with additional breakthrough tumour progression and recurrence after initial chemo-responsiveness further problematic features in STS management. Doxorubicin is a substrate for the multi- drug resistance (mdr) gene product p-glycoprotein drug efflux pump and exerts its main mode of action by induction of DNA double-strand breaks during the S-phase of the cell cycle. Two papers in my thesis characterise different aspects of chemoresistance in sarcoma. The first shows that wild-type p53 suppresses Protein Kinase Calpha (PKCα) phosphorylation (and activation) of p-glycoprotein by transcriptional repression of PKCα through a Sp-1 transcription factor binding site in its -244/-234 promoter region. The second paper demonstrates that Rad51 (a central mediator of homologous recombination repair of double strand breaks) has elevated levels in sarcoma and particularly in the S- G2 phase of the cell cycle. Suppression of Rad51 with small interfering RNA in sarcoma cell culture led to doxorubicin chemosensitisation. Reintroduction of wild-type p53 into STS cell lines resulted in decreased Rad51 protein and mRNA expression via transcriptional repression of the Rad51 promoter through increased AP-2 binding. In light of poor response rates to chemotherapy, escape from local control portends a poor prognosis for patients with sarcoma. Two papers in my thesis characterise aspects of sarcoma angiogenesis, invasion and metastasis. Human sarcoma samples were found to have high levels of matrix metalloproteinase-9 (MMP-9) with expression levels that correlated with p53 mutational status. MMP-9 is known to degrade extracellular collagen, contribute to the control of the angiogenic switch necessary in primary tumour progression and facilitate invasion and metastasis. Reconstitution of wild-type p53 function led to decreased levels of MMP-9 protein and mRNA as well as zymography-assessed MMP-9 proteolytic activity and decreased tumour cell invasiveness. Reintroduction of wild-type p53 into human sarcoma xenografts in-vivo decreased tumour growth and MMP-9 protein expression. Wild-type p53 was found to suppress mmp-9 transcription via decreased binding of NF-κB to its -607/-595 mmp-9 promoter element. Studies on the role of the VEGF165 in sarcoma found that sarcoma cells stably transfected with VEGF165 formed more aggressive xenografted tumours with increased vascularity, growth rate, metastasis, and resistance to chemotherapy. Use of the anti-VEGFR2 antibody DC101 enhanced doxorubicin sensitivity at sub-conventional dosing, inhibited tumour growth, decreased development of metastases, and reduced tumour micro-vessel density while increasing the vessel maturation index. These effects were explained primarily through effects on endothelial cells (e.c.s), rather than the tumour cells per se, where DC101 induced e.c. sensitivity to doxorubicin and suppressed e.c. production of MMPs. The p53 tumour suppressor pathway is the most frequently mutated pathway in sarcoma. Recapitulation of wild-type p53 function in sarcoma exerts a number of anti-cancer outcomes such as growth arrest, resensitisation to chemotherapy, suppression of invasion, and attenuation of angiogenesis. Using a modified nude rat-human sarcoma xenograft model for isolated limb perfusion (ILP) delivery of wild-type p53 in a replication deficient adenovirus vector I showed that functionally competent wild-type p53 could be delivered to and detected in human leiomyosarcoma xenografts confirming preclinical feasibility - although not efficacious due to low transgene expression. Viral fibre modification to express the RGD tripeptide motif led to greater viral uptake by sarcoma cells in vitro (transductional targeting) and changing the transgene promoter to a response element active in cells with active telomerase expression restricted the transgene expression to the tumour intracellular environment (transcriptional targeting). Delivery of the fibre-modified, selectively replication proficient oncolytic adenovirus Ad.hTC.GFP/ E1a.RGD by ILP demonstrated a more robust, and tumour-restricted, transgene expression with evidence of anti-sarcoma effect confirmed microscopically. Collaborative studies using the fibre modified phage RGD-4C AAVP confirmed that systemic delivery specifically, efficiently, and repeatedly targets human sarcoma xenografts, binds to αv integrins in tumours, and demonstrates a durable, though heterogeneous, transgene expression of 1-4 weeks. Incorporation of the Herpes Simplex Virus thymidine kinase (HSVtk) transgene into RGD-4C AAVP permitted CT-PET spatial and temporal molecular imaging in vivo of transgene expression and allowed quantification of tumour metabolic activity both before and after interval administration of a systemic cytotoxic with predictable and measurable response to treatment before becoming apparent clinically. These papers further the medical and scientific community’s understanding of the biology of soft tissue sarcoma and report preclinical studies with novel and promising anti- sarcoma therapeutics.

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Seafood products fraud, the misrepresentation of them, have been discovered all around the world in different forms as false labeling, species substitution, short-weighting or over glazing in order to hide the correct identity, origin or weight of the seafood products. Due to the value of seafood products such as canned tuna, swordfish or grouper, these species are the subject of the commercial fraud is mainly there placement of valuable species with other little or no value species. A similar situation occurs with the shelled shrimp or shellfish that are reduced into pieces for the commercialization. Food fraud by species substitution is an emerging risk given the increasingly global food supply chain and the potential food safety issues. Economic food fraud is committed when food is deliberately placed on the market, for financial gain deceiving consumers (Woolfe, M. & Primrose, S. 2004). As a result of the increased demand and the globalization of the seafood supply, more fish species are encountered in the market. In this scenary, it becomes essential to unequivocally identify the species. The traditional taxonomy, based primarily on identification keys of species, has shown a number of limitations in the use of the distinctive features in many animal taxa, amplified when fish, crustacean or shellfish are commercially transformed. Many fish species show a similar texture, thus the certification of fish products is particularly important when fishes have undergone procedures which affect the overall anatomical structure, such as heading, slicing or filleting (Marko et al., 2004). The absence of morphological traits, a main characteristic usually used to identify animal species, represents a challenge and molecular identification methods are required. Among them, DNA-based methods are more frequently employed for food authentication (Lockley & Bardsley, 2000). In addition to food authentication and traceability, studies of taxonomy, population and conservation genetics as well as analysis of dietary habits and prey selection, also rely on genetic analyses including the DNA barcoding technology (Arroyave & Stiassny, 2014; Galimberti et al., 2013; Mafra, Ferreira, & Oliveira, 2008; Nicolé et al., 2012; Rasmussen & Morrissey, 2008), consisting in PCR amplification and sequencing of a COI mitochondrial gene specific region. The system proposed by P. Hebert et al. (2003) locates inside the mitochondrial COI gene (cytochrome oxidase subunit I) the bioidentification system useful in taxonomic identification of species (Lo Brutto et al., 2007). The COI region, used for genetic identification - DNA barcode - is short enough to allow, with the current technology, to decode sequence (the pairs of nucleotide bases) in a single step. Despite, this region only represents a tiny fraction of the mitochondrial DNA content in each cell, the COI region has sufficient variability to distinguish the majority of species among them (Biondo et al. 2016). This technique has been already employed to address the demand of assessing the actual identity and/or provenance of marketed products, as well as to unmask mislabelling and fraudulent substitutions, difficult to detect especially in manufactured seafood (Barbuto et al., 2010; Galimberti et al., 2013; Filonzi, Chiesa, Vaghi, & Nonnis Marzano, 2010). Nowadays,the research concerns the use of genetic markers to identify not only the species and/or varieties of fish, but also to identify molecular characters able to trace the origin and to provide an effective control tool forproducers and consumers as a supply chain in agreementwith local regulations.

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Australian forest industries have a long history of export trade of a wide range of products from woodchips (for paper manufacturing), sandalwood (essential oils, carving and incense) to high value musical instruments, flooring and outdoor furniture. For the high value group, fluctuating environmental conditions brought on by changes in temperature and relative humidity, can lead to performance problems due to consequential swelling, shrinkage and/or distortion of the wood elements. A survey determined the types of value-added products exported, including species and dimensions packaging used and export markets. Data loggers were installed with shipments to monitor temperature and relative humidity conditions. These data were converted to timber equilibrium moisture content values to provide an indication of the environment that the wood elements would be acclimatising to. The results of the initial survey indicated that primary high value wood export products included guitars, flooring, decking and outdoor furniture. The destination markets were mainly located in the northern hemisphere, particularly the United States of America, China, Hong Kong, Europe (including the United Kingdom), Japan, Korea and the Middle East. Other regions importing Australian-made wooden articles were south-east Asia, New Zealand and South Africa. Different timber species have differing rates of swelling and shrinkage, so the types of timber were also recorded during the survey. Results from this work determined that the major species were ash-type eucalypts from south-eastern Australia (commonly referred to in the market as Tasmanian oak), jarrah from Western Australia, spotted gum, hoop pine, white cypress, black butt, brush box and Sydney blue gum from Queensland and New South Wales. The environmental conditions data indicated that microclimates in shipping containers can fluctuate extensively during shipping. Conditions at the time of manufacturing were usually between 10 and 12% equilibrium moisture content, however conditions during shipping could range from 5 (very dry) to 20% (very humid). The packaging systems incorporated were reported to be efficient at protecting the wooden articles from damage during transit. The research highlighted the potential risk for wood components to ‘move’ in response to periods of drier or more humid conditions than those at the time of manufacturing, and the importance of engineering a packaging system that can account for the environmental conditions experienced in shipping containers. Examples of potential dimensional changes in wooden components were calculated based on published unit shrinkage data for key species and the climatic data returned from the logging equipment. The information highlighted the importance of good design to account for possible timber movement during shipping. A timber movement calculator was developed to allow designers to input component species, dimensions, site of manufacture and destination, to see validate their product design.

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In this thesis I examine a variety of linguistic elements which involve ``alternative'' semantic values---a class arguably including focus, interrogatives, indefinites, and disjunctions---and the connections between these elements. This study focusses on the analysis of such elements in Sinhala, with comparison to Malayalam, Tlingit, and Japanese. The central part of the study concerns the proper syntactic and semantic analysis of Q[uestion]-particles (including Sinhala "da", Malayalam "-oo", Japanese "ka"), which, in many languages, appear not only in interrogatives, but also in the formation of indefinites, disjunctions, and relative clauses. This set of contexts is syntactically-heterogeneous, and so syntax does not offer an explanation for the appearance of Q-particles in this particular set of environments. I propose that these contexts can be united in terms of semantics, as all involving some element which denotes a set of ``alternatives''. Both wh-words and disjunctions can be analysed as creating Hamblin-type sets of ``alternatives''. Q-particles can be treated as uniformly denoting variables over choice functions which apply to the aforementioned Hamblin-type sets, thus ``restoring'' the derivation to normal Montagovian semantics. The treatment of Q-particles as uniformly denoting variables over choice functions provides an explanation for why these particles appear in just this set of contexts: they all include an element with Hamblin-type semantics. However, we also find variation in the use of Q-particles; including, in some languages, the appearance of multiple morphologically-distinct Q-particles in different syntactic contexts. Such variation can be handled largely by positing that Q-particles may vary in their formal syntactic feature specifications, determining which syntactic contexts they are licensed in. The unified analysis of Q-particles as denoting variables over choice functions also raises various questions about the proper analysis of interrogatives, indefinites, and disjunctions, including issues concerning the nature of the semantics of wh-words and the syntactic structure of disjunction. As well, I observe that indefinites involving Q-particles have a crosslinguistic tendency to be epistemic indefinites, i.e. indefinites which explicitly signal ignorance of details regarding who or what satisfies the existential claim. I provide an account of such indefinites which draws on the analysis of Q-particles as variables over choice functions. These pragmatic ``signals of ignorance'' (which I argue to be presuppositions) also have a further role to play in determining the distribution of Q-particles in disjunctions. The final section of this study investigates the historical development of focus constructions and Q-particles in Sinhala. This diachronic study allows us not only to observe the origin and development of such elements, but also serves to delimit the range of possible synchronic analyses, thus providing us with further insights into the formal syntactic and semantic properties of Q-particles. This study highlights both the importance of considering various components of the grammar (e.g. syntax, semantics, pragmatics, morphology) and the use of philology in developing plausible formal analyses of complex linguistic phenomena such as the crosslinguistic distribution of Q-particles.

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Magnetic fields are ubiquitous in galaxy cluster atmospheres and have a variety of astrophysical and cosmological consequences. Magnetic fields can contribute to the pressure support of clusters, affect thermal conduction, and modify the evolution of bubbles driven by active galactic nuclei. However, we currently do not fully understand the origin and evolution of these fields throughout cosmic time. Furthermore, we do not have a general understanding of the relationship between magnetic field strength and topology and other cluster properties, such as mass and X-ray luminosity. We can now begin to answer some of these questions using large-scale cosmological magnetohydrodynamic (MHD) simulations of the formation of galaxy clusters including the seeding and growth of magnetic fields. Using large-scale cosmological simulations with the FLASH code combined with a simplified model of the acceleration of cosmic rays responsible for the generation of radio halos, we find that the galaxy cluster frequency distribution and expected number counts of radio halos from upcoming low-frequency sur- veys are strongly dependent on the strength of magnetic fields. Thus, a more complete understanding of the origin and evolution of magnetic fields is necessary to understand and constrain models of diffuse synchrotron emission from clusters. One favored model for generating magnetic fields is through the amplification of weak seed fields in active galactic nuclei (AGN) accretion disks and their subsequent injection into cluster atmospheres via AGN-driven jets and bubbles. However, current large-scale cosmological simulations cannot directly include the physical processes associated with the accretion and feedback processes of AGN or the seeding and merging of the associated SMBHs. Thus, we must include these effects as subgrid models. In order to carefully study the growth of magnetic fields in clusters via AGN-driven outflows, we present a systematic study of SMBH and AGN subgrid models. Using dark-matter only cosmological simulations, we find that many important quantities, such as the relationship between SMBH mass and galactic bulge velocity dispersion and the merger rate of black holes, are highly sensitive to the subgrid model assumptions of SMBHs. In addition, using MHD calculations of an isolated cluster, we find that magnetic field strengths, extent, topology, and relationship to other gas quantities such as temperature and density are also highly dependent on the chosen model of accretion and feedback. We use these systematic studies of SMBHs and AGN inform and constrain our choice of subgrid models, and we use those results to outline a fully cosmological MHD simulation to study the injection and growth of magnetic fields in clusters of galaxies. This simulation will be the first to study the birth and evolution of magnetic fields using a fully closed accretion-feedback cycle, with as few assumptions as possible and a clearer understanding of the effects of the various parameter choices.

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Los turistas urbanos se caracterizan por ser uno de los segmentos de mayor crecimiento en los mercados turísticos actuales. Monterrey (México), uno de los principales destinos urbanos del país, ha apostado en la actualidad por mejorar su competitividad. Esta investigación se propuso encontrar evidencia acerca de la relación causal de la motivación de viaje sobre la imagen percibida del destino, dos variables importantes por su influencia en la satisfacción de los visitantes. Una revisión de la literatura permitió proponer constructos teóricos integrados en un instrumento para la recogida de datos vía encuesta a una muestra representativa. Por medio del método de regresión y ecuaciones estructurales por mínimos cuadrados parciales (PLS), se identificaron los componentes principales de ambas variables y se obtuvo un modelo explicativo de la imagen percibida del destino en función de la motivación de viaje. Finalmente, se emiten recomendaciones para la gestión del destino urbano en función de los resultados obtenidos. ABSTRACT: Abstract Urban tourists are recognized as one of the fastest growing segments in today’s tourism markets. Monterrey, Mexico, one of the main urban destinations in the country aims at improving its competitiveness. This research work had the purpose of finding evidence on the causal relationship between travel motivation and destination image, two important variables because of their influence on visitors’ satisfaction. A literature review enabled the proposal of a research instrument with theoretically based constructs to gather data through survey from a representative sample. Using regression and structural equations modelling by partial least squares (pls) a set of main components of both variables were identified thus enabling the obtention of a explanatory model of destination image in terms of travel motivations. Finally based on the results some recommendations of tourism management are given.

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This study examined variations in the Fulton condition factor, chemical composition, and stable isotopes of carbon and nitrogen in the Brazilian freshwater fish cachara (Pseudoplatystoma fasciatum), comparing farmed and wild fish in different seasons. Values for energy, protein, moisture, and Fulton's condition factor were higher for farmed than for wild fish in the rainy season, indicating better nutritional quality; however, these differences were not observed in the dry season. Likewise, we found significant enhancement of delta(15)N in farmed fish in the rainy season but not in the dry season, whereas enhancement of delta(13)C was observed in both seasons. The combined measurement of delta(13)C and delta(15)N provided traceability under all conditions. Our findings show that stable isotope analysis of C and N can be used to trace cachara origin, and that seasonal variations need to be considered when applying chemical and isotopic authentication of fish and fish products. (C) 2010 Elsevier Ltd. All rights reserved.

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Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Nevertheless, sometimes it is not possible to extract the archaeological material from the marine environment due to size of the sample, the legislation or preservation purposes. In these cases, the in-situ analysis turns into the only alternative for obtaining information. In spite of this demand, no analytical techniques are available for the in-situ chemical characterization of underwater materials. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. To further exploit the inherent advantages of the technology, a mobile fiber-based LIBS platform capable of performing remote measurements up to 50 meters range has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS) 2. The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In the present work, the design and construction considerations of the instrument are reported and its performance is discussed on the basis of the spectral response, the remote irradiance achieved upon the range of analysis and its influence on plasma properties, as well as the effect of the laser pulse duration and purge gas to the LIBS signal. Also, to check the reliability and reproducibility of the instrument for field analysis several robustness tests were performed outside the lab. Finally, the capability of this instrument was successfully demonstrated in an underwater archaeological shipwreck (San Pedro de Alcántara, Malaga).

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Arm/Rmt methyltransferases have emerged recently in pathogenic bacteria as enzymes that confer high-level resistance to 4,6-disubstituted aminoglycosides through methylation of the G1405 residue in the 16S rRNA (like ArmA and RmtA to -E). In prokaryotes, nucleotide methylations are the most common type of rRNA modification, and they are introduced posttranscriptionally by a variety of site-specific housekeeping enzymes to optimize ribosomal function. Here we show that while the aminoglycoside resistance methyltransferase RmtC methylates G1405, it impedes methylation of the housekeeping methyltransferase RsmF at position C1407, a nucleotide that, like G1405, forms part of the aminoglycoside binding pocket of the 16S rRNA. To understand the origin and consequences of this phenomenon, we constructed a series of in-frame knockout and knock-in mutants of Escherichia coli, corresponding to the genotypes rsmF(+), ΔrsmF, rsmF(+) rmtC(+), and ΔrsmF rmtC(+). When analyzed for the antimicrobial resistance pattern, the ΔrsmF bacteria had a decreased susceptibility to aminoglycosides, including 4,6- and 4,5-deoxystreptamine aminoglycosides, showing that the housekeeping methylation at C1407 is involved in intrinsic aminoglycoside susceptibility in E. coli. Competition experiments between the isogenic E. coli strains showed that, contrary to expectation, acquisition of rmtC does not entail a fitness cost for the bacterium. Finally, matrix-assisted laser desorption ionization (MALDI) mass spectrometry allowed us to determine that RmtC methylates the G1405 residue not only in presence but also in the absence of aminoglycoside antibiotics. Thus, the coupling between housekeeping and acquired methyltransferases subverts the methylation architecture of the 16S rRNA but elicits Arm/Rmt methyltransferases to be selected and retained, posing an important threat to the usefulness of aminoglycosides worldwide.