654 resultados para 992


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Decellularized adipose tissue (DAT) is a promising biomaterial for soft tissue regeneration, and it provides a highly conducive microenvironment for human adipose-derived stem/stromal cell (ASC) attachment, proliferation, and adipogenesis. This thesis focused on developing techniques to fabricate 3-D bioscaffolds from enzymatically-digested DAT as platforms for ASC culture and delivery in adipose tissue engineering and large-scale ASC expansion. Initial work investigated chemically crosslinked microcarriers fabricated from pepsin-digested DAT as injectable adipo-inductive substrates for ASCs. DAT microcarriers highly supported ASC adipogenesis compared to gelatin microcarriers in a CELLSPIN system, as confirmed by glycerol-3-phosphate dehydrogenase (GPDH) enzyme activity, lipid accumulation, and endpoint RT-PCR. ASCs cultured on DAT microcarriers in proliferation medium also had elevated PPARγ, C/EBPα, and LPL expression which suggested adipo-inductive properties. In vivo testing of the DAT microcarriers exhibited stable volume retention and enhanced cellular infiltration, tissue remodeling, and angiogenesis. Building from this work, non-chemically crosslinked porous foams and bead foams were fabricated from α-amylase-digested DAT for soft tissue regeneration. Foams were stable and strongly supported ASC adipogenesis based on GPDH activity and endpoint RT-PCR. PPARγ, C/EBPα, and LPL expression in ASCs cultured on the foams in proliferation media indicated adipo-inductive properties. Foams with Young’s moduli similar to human fat also influenced ASC adipogenesis by enhanced GPDH activity. In vivo adipogenesis accompanied by a potent angiogenic response and rapid resorption showed their potential use in wound healing applications. Finally, non-chemically crosslinked porous microcarriers synthesized from α-amylase-digested DAT were investigated for ASC expansion. DAT microcarriers remained stable in culture and supported significantly higher ASC proliferation compared to Cultispher-S microcarriers in a CELLSPIN system. ASC immunophenotype was preserved for all expanded groups, with reduced adhesion marker expression under dynamic conditions. DAT microcarrier expansion upregulated ASC expression of early adipogenic (PPARγ, LPL) and chondrogenic (COMP) markers without inducing a mature phenotype. DAT microcarrier expanded ASCs also showed similar levels of adipogenesis and osteogenesis compared to Cultispher-S despite a significantly higher population fold-change, and had the highest level of chondrogenesis among all groups. This study demonstrates the promising use of DAT microcarriers as a clinically relevant strategy for ASC expansion while maintaining multilineage differentiation capacity.

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Chemical Stratigraphy, or the study of the variation of chemical elements within sedimentary sequences, has gradually become an experienced tool in the research and correlation of global geologic events. In this paper 87Sr/ 86Sr ratios of the Triassic marine carbonates (Muschelkalk facies) of southeast Iberian Ranges, Iberian Peninsula, are presented and the representative Sr-isotopic curve constructed for the upper Ladinian interval. The studied stratigraphic succession is 102 meters thick, continuous, and well preserved. Previous paleontological data from macro and micro, ammonites, bivalves, foraminifera, conodonts and palynological assemblages, suggest a Fassanian-Longobardian age (Late Ladinian). Although diagenetic minerals are present in small amounts, the elemental data content of bulk carbonate samples, especially Sr contents, show a major variation that probably reflects palaeoenvironmental changes. The 87Sr/86Sr ratios curve shows a rise from 0.707649 near the base of the section to 0.707741 and then declines rapidly to 0.707624, with a final values rise up to 0.70787 in the upper part. The data up to meter 80 in the studied succession is broadly concurrent with 87Sr/86Sr ratios of sequences of similar age and complements these data. Moreover, the sequence stratigraphic framework and its key surfaces, which are difficult to be recognised just based in the facies analysis, are characterised by combining variations of the Ca, Mg, Mn, Sr and CaCO3 contents

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Leíró tanulmányunkban a Budapesti Értéktőzsde két legnagyobb forgalmú részvényének (OTP, Mol) kereskedési jellemzőit tárjuk fel a 2013-as év első 10 hónapjának adatait használva. A limitajánlati könyv alakját a Budapesti Likviditási Mérték adataiból készített három komponenssel jelenítjük meg. A három talált jellemző a meredekség, a konvexitás és a csavarodás. Az ajánlati és tranzakciós árak, valamint a forgalomadatok alapján készített mutatókat felhasználva végezzük az elemzést. Elsőként ismertetjük a kereskedés egyes jellemzőinek napon belüli mintázatait, és azokat összevetjük a szakirodalom által más tőzsdékre megfigyelt alakzatokkal. Ezt követően azt vizsgáljuk, hogy egy-egy piaci ajánlat hogyan módosítja rövid távon a piaci árfolyamot. Ehhez árhatásegyenleteket becsülünk, amelyben külön mérjük az ajánlat méretének hatását és az ajánlat adásának költségességét. Az árhatás egyenleteket azon feltételezés mellett is megbecsüljük, hogy a piaci ajánlatot nyújtók már az ajánlatadás előtt ismerik az ajánlati könyv mélységét. Mérjük a nyitás utáni és a zárás előtti szakaszok hatását is. Végül megvizsgáljuk, hogy miként változnak a vételi és eladási árak, az árrés, valamint az ajánlati könyv alakját leíró főkomponensek, ha egy agresszív (a limitáras szintet elfogyasztó) piaci ajánlat érkezik. Ezzel az ajánlati könyv alakjának mozgását dokumentáljuk, ami a limitajánlatot nyújtó szereplők együttes viselkedését írja le.

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Abstract: In the mid-1990s when I worked for a telecommunications giant I struggled to gain access to basic geodemographic data. It cost hundreds of thousands of dollars at the time to simply purchase a tile of satellite imagery from Marconi, and it was often cheaper to create my own maps using a digitizer and A0 paper maps. Everything from granular administrative boundaries to right-of-ways to points of interest and geocoding capabilities were either unavailable for the places I was working in throughout Asia or very limited. The control of this data was either in a government’s census and statistical bureau or was created by a handful of forward thinking corporations. Twenty years on we find ourselves inundated with data (location and other) that we are challenged to amalgamate, and much of it still “dirty” in nature. Open data initiatives such as ODI give us great hope for how we might be able to share information together and capitalize not only in the crowdsourcing behavior but in the implications for positive usage for the environment and for the advancement of humanity. We are already gathering and amassing a great deal of data and insight through excellent citizen science participatory projects across the globe. In early 2015, I delivered a keynote at the Data Made Me Do It conference at UC Berkeley, and in the preceding year an invited talk at the inaugural QSymposium. In gathering research for these presentations, I began to ponder on the effect that social machines (in effect, autonomous data collection subjects and objects) might have on social behaviors. I focused on studying the problem of data from various veillance perspectives, with an emphasis on the shortcomings of uberveillance which included the potential for misinformation, misinterpretation, and information manipulation when context was entirely missing. As we build advanced systems that rely almost entirely on social machines, we need to ponder on the risks associated with following a purely technocratic approach where machines devoid of intelligence may one day dictate what humans do at the fundamental praxis level. What might be the fallout of uberveillance? Bio: Dr Katina Michael is a professor in the School of Computing and Information Technology at the University of Wollongong. She presently holds the position of Associate Dean – International in the Faculty of Engineering and Information Sciences. Katina is the IEEE Technology and Society Magazine editor-in-chief, and IEEE Consumer Electronics Magazine senior editor. Since 2008 she has been a board member of the Australian Privacy Foundation, and until recently was the Vice-Chair. Michael researches on the socio-ethical implications of emerging technologies with an emphasis on an all-hazards approach to national security. She has written and edited six books, guest edited numerous special issue journals on themes related to radio-frequency identification (RFID) tags, supply chain management, location-based services, innovation and surveillance/ uberveillance for Proceedings of the IEEE, Computer and IEEE Potentials. Prior to academia, Katina worked for Nortel Networks as a senior network engineer in Asia, and also in information systems for OTIS and Andersen Consulting. She holds cross-disciplinary qualifications in technology and law.

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Background The transition to higher education can affect lifestyle-related factors. Objectives: To identify lifestyles of higher education students and analyse the influence of self-esteem and psychological well-being. Methods Correlational cross-sectional study. A total of 4,314 students partici- pated in the study. Online questionnaires were used: Estilo de Vida Fantástico (Fantastic Lifestyle Assessment) [1]; Questionário de Bem- estar Psicológico (Psychological General Well-Being Questionnaire) [2], and Escala de auto-estima de Rosenberg (Rosenberg Self-Esteem Scale [3]. Results Most students (85.3 %) have a healthy lifestyle. Lifestyle is strongly correlated with self-esteem and psychological well-being (p < 0.001). While analysing the association between self-esteem and psycho- logical well-being and the various lifestyle domains according to gen- der, a positive and significant correlation (p < 0.001) was found among female students, except for the Smoking domain (p = 0.393); in relation to psychological well-being, positive correlations were found in all domains. Among male students, positive and significant correlations (p < 0.001) were found in most lifestyle domains and self-esteem, except for the Smoking (p = 0.992), Alcohol and other drugs (p = 0.181) and Other behaviours (p = 0.442) domains; in rela- tion to psychological well-being, positive and significant correlations (p < 0.001) were found in most lifestyle domains, except for the Smoking (p = 0.458) and Other behaviours (p = 0.128) domains. Conclusions Based on the results, higher education institutions should support intervention projects to maintain high levels of psychological well- being and self-esteem, promoting healthy lifestyles.

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En este documento empleamos las series de la Tasa de Cambio Representativa de Mercado y el Índice General de la Bolsa Colombia para ilustrar cuatro hechos estilizados muy conocidos en la literatura financiera: i) las series de precios siguen un camino aleatorio, ii) la distribución de los rendimientos es leptocúrtica y exhibe colas pesadas, iii) a medida que se calculan los rendimientos para períodos más amplios su distribución se acerca más a la distribución normal, y iv) los rendimientos presentan volatilidad agrupada (volatility clustering).

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Glutamine synthetase (GS) is a vital enzyme for the assimilation of ammonia into amino acids in higher plants. In legumes, GS plays a crucial role in the assimilation of the ammonium released by nitrogen-fixing bacteria in root nodules, constituting an important metabolic knob controlling the nitrogen (N) assimilatory pathways. To identify new regulators of nodule metabolism, we profiled the transcriptome of Medicago truncatula nodules impaired in N assimilation by specifically inhibiting GS activity using phosphinothricin (PPT). Global transcript expression of nodules collected before and after PPT addition (4, 8, and 24 h) was assessed using Affymetrix M. truncatula GeneChip arrays. Hundreds of genes were regulated at the three time points, illustrating the dramatic alterations in cell metabolism that are imposed on the nodules upon GS inhibition. The data indicate that GS inhibition triggers a fast plant defense response, induces premature nodule senescence, and promotes loss of root nodule identity. Consecutive metabolic changes were identified at the three time points analyzed. The results point to a fast repression of asparagine synthesis and of the glycolytic pathway and to the synthesis of glutamate via reactions alternative to the GS/GOGAT cycle. Several genes potentially involved in the molecular surveillance for internal organic N availability are identified and a number of transporters potentially important for nodule functioning are pinpointed. The data provided by this study contributes to the mapping of regulatory and metabolic networks involved in root nodule functioning and highlight candidate modulators for functional analysis.

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The feeding habits and biological aspects of the reproductive cycle of two-spot astyanax, Astyanax cf. lacustris (Reinhardt, 1874) were investigated. Fish samples were captured on a monthly basis, using gillnets of 4 cm mesh size, from the Piató Lake, Assu, Rio Grande do Norte, during the period of September, 2006 to August, 2007. Physico-chemical parameters, such as, temperature, electrical conductivity and dissolved oxygen of the lake were registered. The monthly values of rainfall also were obtained. The 360 individuals captured, were measured, weighed, dissected, and stomach weight and the stage of gonadal maturity were registered. The stomach contents analyses were carried out based on volumetric method, points, frequency of occurrence and applying the Index of Relative Importance. The degrees of repletion of the stomachs were determined besides the Index of Repletion relating to feeding activity variations and frequency of ingestion with limnological parameters and rainfall. The food items identified were separated into distinct groups according to their origin. Sex ratio and Gonadosomatic Relation of females were verified to determine the spawning period and fecundity. The physico-chemical parameters presented the following annual mean values: temperature = 28.8ºC, electrical conductivity = 992.5 µS.cm-1; dissolved oxygen = 4.9 mg.L-1 during the study period. The annual mean of the rainfall was 63.5 mm. The results indicate that this species present an omnivorous feeding habit with a tendency towards insectivory, with an increase in feeding activity during the dry season. The aquatic oxygen to interfere very importance in the feeding activity than the others factors physico-chemicals of water and rainfall. There was a predominance of females, with a sex proportion of 1M:7F. The macroscopic characteristics of the ovaries and testicles revealed four stages of gonadal development: immature, maturing, mature and spent. A temporal variation was observed for the gonadal development of males and females. There was reproductive activity through out the year, with peaks in the months of February, April and June to correspond with the rain of precipitation of the region. The mean fecundity was 7.681 mature oocytes, varying from 4.476 to 12.036, with mean of 7.681. There was positive relation between fecundity and body mass. Condition Factor is not an efficient indicator of the reproductive period of this species. The species A. cf. lacustris is an opportunist and is well adapted to the conditions of the semi-arid Caatinga Biome

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Tämän tutkielman aiheena ovat transitiiviset ja intransitiiviset verbiparit ja niiden rektiotäydennykset. Tavoitteena on kuvata frekvenssin ja variaation keinoin, miten edistyneet suomenoppijat (S2-informantit) käyttävät transitiivisia ja intransitiivisia verbejä sekä niiden paikallissijaisia rektiotäydennyksiä ja verrata niiden esiintymiä suomea äidinkielenä puhuvien S1-informanttien esiintymiin. Lisäksi tavoitteena on kuvata aineiston verbiesiintymien finiitti- ja infiniittimuotoja. Tutkielma kuuluu suomi toisena kielenä -alaan ja keskittyy pääosin syntaksiin ja sanastoon. Se on aineistopohjainen korpustutkimus, jonka aineisto on kerätty Turun yliopiston Lauseopin arkiston Edistyneiden suomenoppijoiden korpuksen (LAS2-korpuksen) tenttivastauksista. Tutkielma on poikittaistutkimus, jossa käytetään sekä kvantitatiivista että kvalitatiivista analyysia kuvattaessa ja vertailtaessa esiintymien frekvenssejä ja variaatioita kahdella informanttiryhmällä. Tutkielman aineisto käsittää 1137 verbiesiintymää. Tutkimuskohteena on 22 verbiä, joista puolet on transitiivisia A-kantaverbejä ja puolet intransitiivisia U-johdos-verbejä, esimerkiksi aiheuttaa ja aiheutua. Käsittelen näitä verbejä verbiparikkeina, jotka muodostavat 11 verbiparia. Tuloksena on, että kumpikin informanttiryhmä suosi intransitiivisia verbejä transitiivisiin verbeihin verrattuna, mutta S2-aineistossa intransitiiviverbit (70 %) olivat huomattavasti yleisempiä kuin S1-aineistossa (55 %). Tulosta selitti tenttivastausten kolme frekventeintä verbiä liittyä, kehittyä ja muuttua. Koska S2-aineiston verbien esiintymistä vain 9 % oli niiden verbiparikkien tehtävissä, kanta–johdos-verbiparikkien sekaantumien vähäisyys ja U-johdosverbien yleisyys indikoivat edistyneiden suomenoppijoiden vahvaa kielitaitotasoa. Tutkittavilla verbiesiintymillä oli 992 rektiotäydennysesiintymää, joista 714 eli 72 % oli S2-aineistossa ja 278 eli 28 % S1-aineistossa. Sekä S2- että S1-aineistossa yleisin rektiotäydennyksen sija oli illatiivi ja toiseksi yleisin elatiivi. S1-aineistossa esiintyi viisi rektiotäydennyssijaa, kun taas S2-aineistossa sijoja esiintyi kymmenen. S2-aineiston täydennyssijojen huomattava variaatio selittyi neljällä norminvastaisesti käytetyllä rektiotäydennyssijalla. Verbien ja rektiotäydennysten lisäksi finiittisten ja infiniittisten verbinmuotojen esiintymissä oli aineistokohtaisia eroja. S2-aineistossa infiniittisiä verbinmuotoja esiintyi huomattavasti vähemmän kuin S1-aineistossa. Kompleksisten rakenteiden hallintaa ilmentävät infiniittiverbit eivät siis ole samalla tavalla S2-informanttien vahvuus kuin U-verbit.

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Dentro de las diversas teorías financieras que se enfocan en la asignación óptima de recursos en un portafolio de inversión, la propuesta de Black-Litterman es la única que incorpora las expectativas futuras que tienen los inversionistas sobre los activos en los cuales destinarán sus recursos. En este trabajo se presenta la propuesta de Black-Litterman como una herramienta para mejorar la selección óptima de portafolios y como un insumo que mejora la estructuración de portafolios a través del modelo clásico propuesto por Markowitz. Además de la presentación teórica del modelo de Black-Litterman, se realiza un análisis de caso estructurando un portafolio óptimo sobre el índice COLCAP del mercado de valores colombiano, los resultados muestran que además de permitir incorporar las visiones de los inversionistas, los resultados obtenidos mediante Black-Litterman ayudan a crear mejores portafolios de inversión a través del modelo de Markowitz, tanto en maximización de rendimientos como de minimización de varianza.

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La réalisation de l’évaluation environnementale, en France, est encouragée par l’existence de règlements, lois, directives et normes Européennes (notamment la Directive 2001/42/CE du Parlement européen et du Conseil du 27 juin 2001 relative à l'évaluation des incidences de certains plans et programmes sur l'environnement et la Loi n° 2015-992 du 17 août 2015 relative à la transition énergétique pour la croissance verte). La compréhension du cadre Drivers – Pressures – State – Impacts – Responses permet de replacer les différentes méthodologies dans un cadre conceptuel plus large. Les méthodes d’analyse de flux de matières (Pressures) et d’analyse de cycle de vie (Impacts) sont les deux familles d’évaluation environnementale considérées dans ce travail. C’est plus précisément l’analyse de flux de matières selon Eurostat et l’analyse de cycle de vie territoriale qui ont été appliquées au territoire métropolitain d’Aix-Marseille-Provence. Un état de l’art relevant les études dans lesquelles sont réalisées des analyses de flux de matières a pu montrer que cette famille de méthodes informe sur le métabolisme des territoires à partir de différents types de flux. L’importance des flux indirects et des ressources minérales dans les métabolismes a ainsi été démontrée. Du côté des études analysant les cycles de vie sur les territoires, comme c’est le cas dans l’analyse de cycle de vie territoriale, la distinction faite entre les impacts et dommages, directs ou globaux, permet d’offrir des recommandations ciblées, améliorant la qualité de vie des citoyens. La mise en œuvre de ces deux méthodes sur le territoire métropolitain a mis en évidence l’importance dominante des flux indirects liés aux importations et exportations que génèrent les activités du territoire, elles-mêmes fortement influencées par la présence du port de Marseille-Fos. L’activité pétrochimique, qui caractérise elle aussi la métropole, est une grande consommatrice de combustibles fossiles, ce qui se reflète dans les volumes de flux calculés et leurs impacts associés. Les deux méthodologies s’avèrent complémentaires, chacune ayant ses forces et faiblesses respectives. Pour l’analyse de cycle de vie, la pensée cycle de vie et la prise en compte de la qualité de la matière, d’une part, et la facilité d’application et la marge d’erreur réduite de l’analyse de flux de matières, d’autre part, en plus de leurs résultats complémentaires, justifient un usage hybride pour la prise d’actions ciblées. En effet, la collecte commune des données rend intéressante leur exploitation et l’interprétation croisée de leurs résultats.

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The goal of environmental education is ultimately to enable a person to strive for and to attain a more ecological way of life. In this article, we begin by distinguishing three forms of environmental knowledge and go on to predict that people's attitude toward nature represents the force that drives their ecological behavioral engagement. Based on data from 1,907 students, we calibrated previously established instruments to measure ecological behavior, environmental knowledge, and attitude toward nature with Rasch-type models. Using path modeling, we corroborated our theoretically anticipated competence structure. While environmental knowledge revealed a modest behavioral effect, attitude toward nature turned out to be, as expected, the stronger determinant of behavior. Overall, we propose a competence model that has the potential to guide us into more evidence-based ways of promoting the overall ecological engagement of individuals. (DIPF/Orig.)