806 resultados para galaxies: individual (Centaurus A)
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Cytotoxic T cells recognize, via their T cell receptors (TCRs), small antigenic peptides presented by the major histocompatibility complex (pMHC) on the surface of professional antigen-presenting cells and infected or malignant cells. The efficiency of T cell triggering critically depends on TCR binding to cognate pMHC, i.e., the TCR-pMHC structural avidity. The binding and kinetic attributes of this interaction are key parameters for protective T cell-mediated immunity, with stronger TCR-pMHC interactions conferring superior T cell activation and responsiveness than weaker ones. However, high-avidity TCRs are not always available, particularly among self/tumor antigen-specific T cells, most of which are eliminated by central and peripheral deletion mechanisms. Consequently, systematic assessment of T cell avidity can greatly help distinguishing protective from non-protective T cells. Here, we review novel strategies to assess TCR-pMHC interaction kinetics, enabling the identification of the functionally most-relevant T cells. We also discuss the significance of these technologies in determining which cells within a naturally occurring polyclonal tumor-specific T cell response would offer the best clinical benefit for use in adoptive therapies, with or without T cell engineering.
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The objective of this research was to study the role of key individuals in facilitation of technology enabled bottom-up innovation in large organization context. The development of innovation was followed from the point of view of individual actor (key individual) in two cases, through three levels: individual, team and organization, by using knowledge creation and innovation models. This study provides theoretical synthesis and framework through which the study is driven. The results of the study indicate, that in bottom-up initiated innovations the role of key individuals is still crucial, but innovation today is collective effort and there acts several entrepreneurial key individuals: innovator, user champion and organizational sponsor, whose collaboration and developing interaction drives innovation further. The team work is functional and fluent, but it meets great problems in interaction with organization. The large organizations should develop its practices and ability to react on emerging bottom-up initiations, in order to embed innovation to organization and gain sustainable innovation. In addition, bottom-up initiated innovations are demonstrations of peoples knowing, tacit knowledge and therefore renewing of an organization.
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Pensions together with savings and investments during active life are key elements of retirement planning. Motivation for personal choices about the standard of living, bequest and the replacement ratio of pension with respect to last salary income must be considered. This research contributes to the financial planning by helping to quantify long-term care economic needs. We estimate life expectancy from retirement age onwards. The economic cost of care per unit of service is linked to the expected time of needed care and the intensity of required services. The expected individual cost of long-term care from an onset of dependence is estimated separately for men and women. Assumptions on the mortality of the dependent people compared to the general population are introduced. Parameters defining eligibility for various forms of coverage by the universal public social care of the welfare system are addressed. The impact of the intensity of social services on individual predictions is assessed, and a partial coverage by standard private insurance products is also explored. Data were collected by the Spanish Institute of Statistics in two surveys conducted on the general Spanish population in 1999 and in 2008. Official mortality records and life table trends were used to create realistic scenarios for longevity. We find empirical evidence that the public long-term care system in Spain effectively mitigates the risk of incurring huge lifetime costs. We also find that the most vulnerable categories are citizens with moderate disabilities that do not qualify to obtain public social care support. In the Spanish case, the trends between 1999 and 2008 need to be further explored.
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Objetivo: explorar la identificación de los factores individuales de complejidad de cuidados en enfermos hospitalizados. Método: se empleó un diseño cualitativo de investigación-acción participativa con el método de análisis directo de contenido de los breves relatos de los participantes, enfermeras y enfermeros de los hospitales del lnstituto Catalán de la Salud, sobre casos en los que hubieran experimentado situaciones de complejidad. La suficiencia muestral se estableció a partir del criterio de saturación de la información. Los participantes fueron invitados a formar parte de una ronda de talleres/sesiones de discusión que se hicieron durante 18 meses. Uno de los investigadores recogía por escrito las opiniones de los participantes, mientras el otro moderaba el debate y realizaba preguntas reflexivas sobre el contenido de la propuesta. Posteriormente se invitaba a los participantes a organizarse en pequeños grupos para discutir y registrar en un fomulario individual, breves narrativas sobre casos en los que hubieran experimentado situaciones de complejidad. Resultados: el número de relatos breves incluidos en el análisis final fue de 287. Los factores individuales de complejidad de cuidados incluye cinco dominios: (1) evolutivo, (2) mental y cognitivo, (3) psicoemocional, (4) sociocultural y (5) comorbilidad y complicaciones. La complejidad individual de cuidados se estructura fuentes, factores y especificaciones. Conclusiones: de los cinco ejes de complejidad identificados en el Modelo Vectorial de Complejidad de Safford, cuatro coinciden parcialmente con el análisis presentado. La arquitectura de la complejidad de cuidados debería incluir una consideración multiperspectiva, incluyendo los ejes de complejidad individual, terapéutica-procedimental y organizativa.
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Objetivo: explorar la identificación de los factores individuales de complejidad de cuidados en enfermos hospitalizados. Método: se empleó un diseño cualitativo de investigación-acción participativa con el método de análisis directo de contenido de los breves relatos de los participantes, enfermeras y enfermeros de los hospitales del lnstituto Catalán de la Salud, sobre casos en los que hubieran experimentado situaciones de complejidad. La suficiencia muestral se estableció a partir del criterio de saturación de la información. Los participantes fueron invitados a formar parte de una ronda de talleres/sesiones de discusión que se hicieron durante 18 meses. Uno de los investigadores recogía por escrito las opiniones de los participantes, mientras el otro moderaba el debate y realizaba preguntas reflexivas sobre el contenido de la propuesta. Posteriormente se invitaba a los participantes a organizarse en pequeños grupos para discutir y registrar en un fomulario individual, breves narrativas sobre casos en los que hubieran experimentado situaciones de complejidad. Resultados: el número de relatos breves incluidos en el análisis final fue de 287. Los factores individuales de complejidad de cuidados incluye cinco dominios: (1) evolutivo, (2) mental y cognitivo, (3) psicoemocional, (4) sociocultural y (5) comorbilidad y complicaciones. La complejidad individual de cuidados se estructura fuentes, factores y especificaciones. Conclusiones: de los cinco ejes de complejidad identificados en el Modelo Vectorial de Complejidad de Safford, cuatro coinciden parcialmente con el análisis presentado. La arquitectura de la complejidad de cuidados debería incluir una consideración multiperspectiva, incluyendo los ejes de complejidad individual, terapéutica-procedimental y organizativa.
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CSL is a key transcription factor, mostly acting as a repressor, which has been shown to have a highly context-dependent function. While known as the main effector of Notch signaling, it can also exert Notch-independent functions. The downstream effects of the Notch/CSL signaling pathway and its involvement in several biological processes have been intensively studied. We recently showed that CSL is important to maintain skin homeostasis, as its specific deletion in mouse dermal fibroblasts -or downmodulation in human stromal fibroblasts- creates an inducing environment for squamous cell carcinoma (SCC) development, possibly due to the conversion of stromal fibroblasts into cancer associated fibroblasts (CAFs). Despite the wide interest in CSL as a transcriptional regulator, the mechanism of its own regulation has so far been neglected. We show here that CSL expression levels differ between individuals, and correlate among others with genes involved in DNA damage response. Starting from this finding we show that in dermal fibroblasts CSL is under transcriptional control of stress inducers such as UVA irradiation and Reactive Oxygen Species (ROS) induction, and that a main player in CSL transcriptional regulation is the transcription factor p53. In a separate line of work, we focused on individual variability, studying the differences in gene expression between human populations in various cancer types, particularly focusing on the Caucasian and African populations. It is indeed widely known that these populations have different incidences and mortalities for various cancers, and response to cancer treatment may also vary between them. We show here several genes that are differentially expressed and could be of interest in the study of population differences in cancer. -- CSL est un facteur de transcription agissant essentiellement comme répresseur, et qui a une fonction hautement dépendant du contexte. C'est l'effecteur principal de la voie de signalisation de Notch, mais il peut également exercer ses fonctions dans une façon Notch- indépendante. Nous avons récemment montré que CSL est important pour maintenir l'homéostasie de la peau. Sa suppression spécifique dans les fibroblastes dermiques de la souris ou dans les fibroblastes stromales humaines crée un environnement favorable pour le développement du carcinome épidermoïde (SCC), probablement en raison de la conversion des fibroblastes en fibroblastes associé au cancer (CAF). Malgré le grand intérêt de CSL comme régulateur transcriptionnel, le mécanisme de sa propre régulation a été jusqu'ici négligée. Nous montrons ici que dans les fibroblastes dermiques CSL est sous le contrôle transcriptionnel de facteurs de stress tels que l'irradiation UVA et l'induction des ROS dont p53 est l'acteur principal de cette régulation. Nous montrons aussi que les niveaux d'expression de CSL varient selon les individus, en corrélation avec d'autres gènes impliqués dans la réponse aux dommages de l'ADN. Dans une autre axe de recherche, concernant la variabilité individuelle, nous avons étudié les différences dans l'expression des gènes dans différents types de cancer entre les populations humaines, en se concentrant particulièrement sur les populations africaines et caucasiennes. Il est en effet bien connu que ces populations montrent des variations dans l'incidence des cancers, la mortalité, ainsi que pour les réponses au traitement. Nous montrons ici plusieurs gènes qui sont exprimés différemment et pourraient être digne d'intérêt dans l'étude du cancer au sein de différentes populations.
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The evolution of cooperation is thought to be promoted by pleiotropy, whereby cooperative traits are coregulated with traits that are important for personal fitness. However, this hypothesis faces a key challenge: what happens if mutation targets a cooperative trait specifically rather than the pleiotropic regulator? Here, we explore this question with the bacterium Pseudomonas aeruginosa, which cooperatively digests complex proteins using elastase. We empirically measure and theoretically model the fate of two mutants-one missing the whole regulatory circuit behind elastase production and the other with only the elastase gene mutated-relative to the wild-type (WT). We first show that, when elastase is needed, neither of the mutants can grow if the WT is absent. And, consistent with previous findings, we show that regulatory gene mutants can grow faster than the WT when there are no pleiotropic costs. However, we find that mutants only lacking elastase production do not outcompete the WT, because the individual cooperative trait has a low cost. We argue that the intrinsic architecture of molecular networks makes pleiotropy an effective way to stabilize cooperative evolution. Although individual cooperative traits experience loss-of-function mutations, these mutations may result in weak benefits, and need not undermine the protection from pleiotropy.
The personal research portal : web 2.0 driven individual commitment with open access for development
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Peer-reviewed
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The objective of this master’s thesis was to examine how corporate values come true among the white-collar employees in the case organization. It was also studied if values were perceived similarly in the different departments. Impact of organizational position and education on value orientation was tested through hypotheses based on earlier values research. There are only few value scales available for measuring organizational values. The empirical study results indicate that personnel’s perception of organizational values can be measured statistically. When defining the scale it is utmost important to link the questions and claims close to the employees’ daily working environment. In this study, Work ethic appeared as the strongest organizational value reflecting respondents’ commitment to their duties. Related to corporate values, Performance was perceived as the strongest value and Emphasis on people the weakest. Value consensus between the departments varied. According to the previous research organizational position and educational level has an impact on value perceptions. In this study, employees in superior position or with higher education perceived organizational values to come true better than subordinates or employees with lower education. Empirical data (N=229) was collected by a web-based survey questionnaire among white-collar employees in the case organization in April 2008. Statistical analyses were performed by SPSS programme.
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We sometimes vividly remember things that did not happen, a phenomenon with general relevance, not only in the courtroom. It is unclear to what extent individual differences in false memories are driven by anatomical differences in memory-relevant brain regions. Here we show in humans that microstructural properties of different white matter tracts as quantified using diffusion tensor imaging are strongly correlated with true and false memory retrieval. To investigate these hypotheses, we tested a large group of participants in a version of the Deese-Roediger-McDermott paradigm (recall and recognition) and subsequently obtained diffusion tensor images. A voxel-based whole-brain level linear regression analysis was performedto relatefractional anisotropyto indices oftrue andfalse memory recall and recognition. True memory was correlated to diffusion anisotropy in the inferior longitudinal fascicle, the major connective pathway of the medial temporal lobe, whereas a greater proneness to retrieve false items was related to the superior longitudinal fascicle connecting frontoparietal structures. Our results show that individual differences in white matter microstructure underlie true and false memory performance.
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Background: Recent research based on comparisons between bilinguals and monolinguals postulates that bilingualism enhances cognitive control functions, because the parallel activation of languages necessitates control of interference. In a novel approach we investigated two groups of bilinguals, distinguished by their susceptibility to cross-language interference, asking whether bilinguals with strong language control abilities ('non-switchers") have an advantage in executive functions (inhibition of irrelevant information, problem solving, planning efficiency, generative fluency and self-monitoring) compared to those bilinguals showing weaker language control abilities ('switchers"). Methods: 29 late bilinguals (21 women) were evaluated using various cognitive control neuropsychological tests [e.g., Tower of Hanoi, Ruff Figural Fluency Task, Divided Attention, Go/noGo] tapping executive functions as well as four subtests of the Wechsler Adult Intelligence Scale. The analysis involved t-tests (two independent samples). Non-switchers (n = 16) were distinguished from switchers (n = 13) by their performance observed in a bilingual picture-naming task. Results: The non-switcher group demonstrated a better performance on the Tower of Hanoi and Ruff Figural Fluency task, faster reaction time in a Go/noGo and Divided Attention task, and produced significantly fewer errors in the Tower of Hanoi, Go/noGo, and Divided Attention tasks when compared to the switchers. Non-switchers performed significantly better on two verbal subtests of the Wechsler Adult Intelligence Scale (Information and Similarity), but not on the Performance subtests (Picture Completion, Block Design). Conclusions: The present results suggest that bilinguals with stronger language control have indeed a cognitive advantage in the administered tests involving executive functions, in particular inhibition, self-monitoring, problem solving, and generative fluency, and in two of the intelligence tests. What remains unclear is the direction of the relationship between executive functions and language control abilities.
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In this dissertation, Active Galactic Nuclei (AGN) and their host galaxies are discussed. Together with transitional events, such as supernovae and gamma-ray bursts, AGN are the most energetic phenomena in the Universe. The dominant fraction of their luminosity originates from the center of a galaxy, where accreting gas falls into a supermassive black hole, converting gravitational energy to radiation. AGN have a wide range of observed properties: e.g. in their emission lines, radio emission, and variability. Most likely, these properties depend significantly on their orientation to our line-of-sight, and to unify AGN into physical classes it is crucial to observe their orientation-independent properties, such as the host galaxies. Furthermore, host galaxy studies are essential to understand the formation and co-evolution of galactic bulges and supermassive black holes. In this thesis, the main focus is on observationally characterizing AGN host galaxies using optical and near-infrared imaging and spectroscopy. BL Lac objects are a class of AGN characterized by rapidly variable and polarized continuum emission across the electromagnetic spectrum, and coredominated radio emission. The near-infrared properties of intermediate redshift BL Lac host galaxies are studied in Paper I. They are found to be large elliptical galaxies that are more luminous than their low redshift counterparts suggesting a strong luminosity evolution, and a contribution from a recent star formation episode. To analyze the stellar content of galaxies in more detail multicolor data, especially observations at blue wavelengths, are essential. In Paper III, optical - near-infrared colors and color gradients are derived for low redshift BL Lac host galaxies. They show bluer colors and steeper color gradients than inactive ellipticals which, most likely, are caused by a relatively young stellar population indicating a different evolutionary stage between AGN hosts and inactive ellipticals. In Paper II, near-infrared imaging of intermediate redshift radio-quiet quasar hosts is used to study their luminosity evolution. The hosts are large elliptical galaxies, but they are systematically fainter than the hosts of radio-loud quasars at similar redshifts, suggesting a link between the luminosity of the host galaxies and the radio properties of AGN. In Paper IV, the characteristics of near-infrared stellar absorption features of low redshift radio galaxies are compared with those of inactive early-type galaxies. The comparison suggests that early-type galaxies with AGN are in a different evolutionary stage than their inactive counterparts. Moreover, radio galaxies are found to contain stellar populations containing both old and intermediate age components.
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Automobile bodily injury (BI) claims remain unsettled for a long time after the accident. The estimation of an accurate reserve for Reported But Not Settled (RBNS) claims is therefore vital for insurers. In accordance with the recommendation included in the Solvency II project (CEIOPS, 2007) a statistical model is here implemented for RBNS reserve estimation. Lognormality on empirical compensation cost data is observed for different levels of BI severity. The individual claim provision is estimated by allocating the expected mean compensation for the predicted severity of the victim’s injury, for which the upper bound is also computed. The BI severity is predicted by means of a heteroscedastic multiple choice model, because empirical evidence has found that the variability in the latent severity of injured individuals travelling by car is not constant. It is shown that this methodology can improve the accuracy of RBNS reserve estimation at all stages, as compared to the subjective assessment that has traditionally been made by practitioners.