958 resultados para A Modification of de la Escalera’s Algorithm
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Background: Heavy-flavor production in p + p collisions is a good test of perturbative-quantum-chromodynamics (pQCD) calculations. Modification of heavy-flavor production in heavy-ion collisions relative to binary-collision scaling from p + p results, quantified with the nuclear-modification factor (R-AA), provides information on both cold-and hot-nuclear-matter effects. Midrapidity heavy-flavor R-AA measurements at the Relativistic Heavy Ion Collider have challenged parton-energy-loss models and resulted in upper limits on the viscosity-entropy ratio that are near the quantum lower bound. Such measurements have not been made in the forward-rapidity region. Purpose: Determine transverse-momentum (p(T)) spectra and the corresponding R-AA for muons from heavy-flavor meson decay in p + p and Cu + Cu collisions at root s(NN) = 200 GeV and y = 1.65. Method: Results are obtained using the semileptonic decay of heavy-flavor mesons into negative muons. The PHENIX muon-arm spectrometers measure the p(T) spectra of inclusive muon candidates. Backgrounds, primarily due to light hadrons, are determined with a Monte Carlo calculation using a set of input hadron distributions tuned to match measured-hadron distributions in the same detector and statistically subtracted. Results: The charm-production cross section in p + p collisions at root s = 200 GeV, integrated over p(T) and in the rapidity range 1.4 < y < 1.9, is found to be d(sigma e (e) over bar)/dy = 0.139 +/- 0.029 (stat)(-0.058)(+0.051) (syst) mb. This result is consistent with a perturbative fixed-order-plus-next-to-leading-log calculation within scale uncertainties and is also consistent with expectations based on the corresponding midrapidity charm-production cross section measured by PHENIX. The R-AA for heavy-flavor muons in Cu + Cu collisions is measured in three centrality bins for 1 < p(T) < 4 GeV/c. Suppression relative to binary-collision scaling (R-AA < 1) increases with centrality. Conclusions: Within experimental and theoretical uncertainties, the measured charm yield in p + p collisions is consistent with state-of-the-art pQCD calculations. Suppression in central Cu + Cu collisions suggests the presence of significant cold-nuclear-matter effects and final-state energy loss.
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INTRODUCTION: With the aim of searching genetic factors associated with the response to an immune treatment based on autologous monocyte-derived dendritic cells pulsed with autologous inactivated HIV, we performed exome analysis by screening more than 240,000 putative functional exonic variants in 18 HIV-positive Brazilian patients that underwent the immune treatment. METHODS: Exome analysis has been performed using the ILLUMINA Infinium HumanExome BeadChip. zCall algorithm allowed us to recall rare variants. Quality control and SNP-centred analysis were done with GenABEL R package. An in-house implementation of the Wang method permitted gene-centred analysis. RESULTS: CCR4-NOT transcription complex, subunit 1 (CNOT1) gene (16q21), showed the strongest association with the modification of the response to the therapeutic vaccine (p=0.00075). CNOT1 SNP rs7188697 A/G was significantly associated with DC treatment response. The presence of a G allele indicated poor response to the therapeutic vaccine (p=0.0031; OR=33.00; CI=1.74-624.66), and the SNP behaved in a dominant model (A/A vs. A/G+G/G p=0.0009; OR=107.66; 95% CI=3.85-3013.31), being the A/G genotype present only in weak/transient responders, conferring susceptibility to poor response to the immune treatment. DISCUSSION: CNOT1 is known to be involved in the control of mRNA deadenylation and mRNA decay. Moreover, CNOT1 has been recently described as being involved in the regulation of inflammatory processes mediated by tristetraprolin (TTP). The TTP-CCR4-NOT complex (CNOT1 in the CCR4-NOT complex is the binding site for TTP) has been reported as interfering with HIV replication, through post-transcriptional control. Therefore, we can hypothesize that genetic variation occurring in the CNOT1 gene could impair the TTP-CCR4-NOT complex, thus interfering with HIV replication and/or host immune response. CONCLUSIONS: Being aware that our findings are exclusive to the 18 patients studied with a need for replication, and that the genetic variant of CNOT1 gene, localized at intron 3, has no known functional effect, we propose a novel potential candidate locus for the modulation of the response to the immune treatment, and open a discussion on the necessity to consider the host genome as another potential variant to be evaluated when designing an immune therapy study
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Although Recovery is often defined as the less studied and documented phase of the Emergency Management Cycle, a wide literature is available for describing characteristics and sub-phases of this process. Previous works do not allow to gain an overall perspective because of a lack of systematic consistent monitoring of recovery utilizing advanced technologies such as remote sensing and GIS technologies. Taking into consideration the key role of Remote Sensing in Response and Damage Assessment, this thesis is aimed to verify the appropriateness of such advanced monitoring techniques to detect recovery advancements over time, with close attention to the main characteristics of the study event: Hurricane Katrina storm surge. Based on multi-source, multi-sensor and multi-temporal data, the post-Katrina recovery was analysed using both a qualitative and a quantitative approach. The first phase was dedicated to the investigation of the relation between urban types, damage and recovery state, referring to geographical and technological parameters. Damage and recovery scales were proposed to review critical observations on remarkable surge- induced effects on various typologies of structures, analyzed at a per-building level. This wide-ranging investigation allowed a new understanding of the distinctive features of the recovery process. A quantitative analysis was employed to develop methodological procedures suited to recognize and monitor distribution, timing and characteristics of recovery activities in the study area. Promising results, gained by applying supervised classification algorithms to detect localization and distribution of blue tarp, have proved that this methodology may help the analyst in the detection and monitoring of recovery activities in areas that have been affected by medium damage. The study found that Mahalanobis Distance was the classifier which provided the most accurate results, in localising blue roofs with 93.7% of blue roof classified correctly and a producer accuracy of 70%. It was seen to be the classifier least sensitive to spectral signature alteration. The application of the dissimilarity textural classification to satellite imagery has demonstrated the suitability of this technique for the detection of debris distribution and for the monitoring of demolition and reconstruction activities in the study area. Linking these geographically extensive techniques with expert per-building interpretation of advanced-technology ground surveys provides a multi-faceted view of the physical recovery process. Remote sensing and GIS technologies combined to advanced ground survey approach provides extremely valuable capability in Recovery activities monitoring and may constitute a technical basis to lead aid organization and local government in the Recovery management.
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A one-dimensional multi-component reactive fluid transport algorithm, 1DREACT (Steefel, 1993) was used to investigate different fluid-rock interaction systems. A major short coming of mass transport calculations which include mineral reactions is that solid solutions occurring in many minerals are not treated adequately. Since many thermodynamic models of solid solutions are highly non-linear, this can seriously impact on the stability and efficiency of the solution algorithms used. Phase petrology community saw itself faced with a similar predicament 10 years ago. To improve performance and reliability, phase equilibrium calculations have been using pseudo compounds. The same approach is used here in the first, using the complex plagioclase solid solution as an example. Thermodynamic properties of a varying number of intermediate plagioclase phases were calculated using ideal molecular, Al-avoidance, and non-ideal mixing models. These different mixing models can easily be incorporated into the simulations without modification of the transport code. Simulation results show that as few as nine intermediate compositions are sufficient to characterize the diffusional profile between albite and anorthite. Hence this approach is very efficient, and can be used with little effort. A subsequent chapter reports the results of reactive fluid transport modeling designed to constrain the hydrothermal alteration of Paleoproterozoic sediments of the Southern Lake Superior region. Field observations reveal that quartz-pyrophyllite (or kaolinite) bearing assemblages have been transformed into muscovite-pyrophyllite-diaspore bearing assemblages due to action of fluids migrating along permeable flow channels. Fluid-rock interaction modeling with an initial qtz-prl assemblage and a K-rich fluid simulates the formation of observed mineralogical transformation. The bulk composition of the system evolves from an SiO2-rich one to an Al2O3+K2O-rich one. Simulations show that the fluid flow was up-temperature (e.g. recharge) and that fluid was K-rich. Pseudo compound approach to include solid solutions in reactive transport models was tested in modeling hydrothermal alteration of Icelandic basalts. Solid solutions of chlorites, amphiboles and plagioclase were included as the secondary mineral phases. Saline and fresh water compositions of geothermal fluids were used to investigate the effect of salinity on alteration. Fluid-rock interaction simulations produce the observed mineral transformations. They show that roughly the same alteration minerals are formed due to reactions with both types of fluid which is in agreement with the field observations. A final application is directed towards the remediation of nitrate rich groundwaters. Removal of excess nitrate from groundwater by pyrite oxidation was modeled using the reactive fluid transport algorithm. Model results show that, when a pyrite-bearing, permeable zone is placed in the flow path, nitrate concentration in infiltrating water can be significantly lowered, in agreement with proposals from the literature. This is due to nitrogen reduction. Several simulations investigate the efficiency of systems with different mineral reactive surface areas, reactive barrier zone widths, and flow rates to identify the optimum setup.
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I temi della ricerca riguardano il rapporto fra avvento del web e la modificazione dei processi di formazione di identità personale e sociale, della percezione dello spazio e del tempo, del prosumerismo digitale e delle varie forme di partecipazione ed associazione. Centrale è stata l’analisi del rapporto fra il Web 2.0 e la trasformazione delle forme di comunicazione a vari livelli, sia personali che sociali. Partendo da una analisi dei contesti socio-economici globali che hanno trasformato la società moderna nella società informazionale, è stato impostato un percorso di ricerca che approfondisse gli attuali criteri di strutturazione della propria identità, alla luce dell’avvento dei social network e delle reti virtuali di comunicazione come strumento preferenziale di socializzazione. La realtà delle reti sociali è stata analizzata in un’ottica di aggregazione spontanea mirata tanto alla comunicazione quanto alla tutela dei consumatori, e le trasformazioni portate dal Web 2.0 sono state la chiave di lettura per ridefinire i parametri della partecipazione dal basso generata dalla rete. Per comprendere la portata di tali trasformazioni nel contesto italiano è stato impostato un paragone tra l’uso del web negli Stati Uniti e in Italia, avendo le recente campagne elettorali dimostrato l’importanza del web nella partecipazione politica bottom-up; il percorso di ricerca ha dunque affrontato una comparazione di due casi, quello italiano e quello statunitense, finalizzato a comprendere l’attuale ruolo dell’utente nelle dinamiche di comunicazione mediatica. Per focalizzare al meglio le trasformazioni sociali generate dalla partecipazione on line è stato infine analizzato il caso del citizen journalism, per misurare, attraverso la metodologia dell’etnografia digitale, l’entità delle trasformazioni in corso. Il portale di giornalismo partecipativo YouReporter è stato il contesto privilegiato dove poter verificare le ipotesi iniziali circa le dinamiche di partecipazione, e il supporto di programmi di elaborazione statistica netnografica ha permesso di destrutturare al meglio tali dinamiche.
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Questa tesi descrive lo sviluppo di un elettrodo modificato con un polimero isolante per la determinazione indiretta del radicale OH. I polimeri testati sono stati polifenolo, polipirrolo e polipirrolo sovraoossidato ed il primo è risultato quello con le migliori prestazioni. Il film di modificante è stato depositato per elettropolimerizzazione del fenolo in ambiente acido, su un elettrodo di carbone vetroso (GC) ed è risultato isolante e perfettamente adeso al GC, impedendo il trasferimento di carica alle più comuni sonde redox. L’attacco dei radicali OH, generati dalla reazione di Fenton o dalla fotolisi di H2O2, rimuove parzialmente il polimero dal GC, ripristinando parzialmente il comportamento conduttore dell’elettrodo. L’entità della degradazione del film polifenolico è stata valutata sfruttando la corrente relativa alla sonda redox Ru(NH3)63+, che rappresenta il segnale analitico per la determinazione del radicale OH. L’elettrodo è stato impiegato per stimare le prestazioni di foto catalizzatori a base di nanoparticelle di TiO2, ottenendo risultati correlati a quelli ricavati da un metodo HPLC. Inoltre esso è stato usato per sviluppare una nuova procedura per la determinazione della capacità di scavenging verso i radicali OH, che è stata applicata all’analisi di composti puri e campioni reali. I risultati erano confrontabili con quelli determinati con metodiche standardizzate, comunemente impiegate per la determinazione della capacità antiossidante. Inoltre è stato condotto uno studio riguardante la modifica di un elettrodo di platino con un idrossido misto a strati a base di cobalto e alluminio (LDH). In particolare si sono valutati gli effetti di diversi pretrattamenti del Pt sulle caratteristiche e prestazioni elettrocatalitiche del film di LDH nei confronti dell’ossidazione di anilina, fenolo e acido salicilico. Questi composti possono essere impiegati come molecole sonda per la determinazione del radicale OH e rivestono interesse da un punto di vista elettroanalitico perché portano facilmente alla passivazione della superficie di Pt.
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Objectives: The aim of this research was to evaluate the impact of Cardiac Rehabilitation (CR) on risky lifestyles, quality of life, psychopathology, psychological distress and well-being, considering the potential moderating role of depression, anxiety and psychosomatic syndromes on lifestyles modification. The influence of CR on cardiac morbidity and mortality was also evaluated. Methods: The experimental group (N=108), undergoing CR, was compared to a control group (N=85) of patients affected by cardiovascular diseases, not undergoing CR, at baseline and at 1-month, 6- and 12-months follow-ups. The assessment included: the Structured Clinical Interview for DSM-IV, the structured interview based on Diagnostic Criteria for Psychosomatic Research (DCPR), GOSPEL questionnaire on lifestyles, Pittsburgh Sleep Quality Index, Morisky Medication Adherence Scale, MOS 36-Item Short Form Health Survey, Symptom Questionnaire, Psychological Well-Being Scale and 14-items Type D Scale. Results: Compared to the control group, CR was associated to: maintenance of the level of physical activity, improvement of correct dietary behaviors and stress management, enhancement of quality of life and sleep; reduction of the most frequently observed psychiatric diagnoses and psychosomatic syndromes at baseline. On the contrary, CR was not found to be associated with: healthy dietary habits, weight loss and improvement on medications adherence. In addition, there were no relevant effects on sub-clinical psychological distress and well-being, except for personal growth and purpose in life (PWB). Also, CR did not seem to play a protective role against cardiac recurrences. The presence of psychosomatic syndromes and depressive disorders was a mediating factor on the modification of specific lifestyles. Conclusions: The findings highlight the need of a psychosomatic assessment and an evaluation of psychological sub-clinical symptomatology in cardiac rehabilitation, in order to identify and address specific factors potentially associated with the clinical course of the heart disease.
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Although the period of the historic “Celtic migrations” is archaeologically extensively studied, the long-lasting question whether mass migration or increased individual mobility caused the expansion of the La Tène culture throughout continental Europe persist. Strontium (Sr) and in part oxygen (O) isotope analysis of human remains from the early La Tène cemeteries of Nebringen (Germany), Münsingen-Rain (Switzerland), Monte Bibele (Italy) and the Czech cemeteries of Radovesice I, Radovesice II and Kutná Hora was, therefore, carried out to investigate the importance of residential changes during this time period. These isotope analyses showed that most analysed individuals either came from the area they were buried in or from the surrounding area of the cemetery. An exception was formed by the Czech cemeteries, where almost a quarter of the studied individuals appeared non-local. Together with Nebringen, these cemeteries also had the most varied Sr isotope ratios, which suggest highly mobile communities in which individuals regularly changed their residency. The isotopic ratios of the cemeteries of Münsingen-Rain and Monte Bibele appeared far less varied. In part, these differences might be explained by the community structures of these cemeteries. Morphological kinship analysis in Münsingen-Rain demonstrated biological relatedness among most of the analysed individuals. These related individuals also shared similar isotope signatures, which suggest an origin from the surrounding Aar Valley. In the vicinity of the cemetery of Monte Bibele, an associated settlement site was discovered. The deceased presumably not only shared this settlement, but also cultivated the same land plots. Dispersed settlement structures were suggested for Nebringen, Radovesice and Kutná Hora, as these agriculturally favourable landscapes were densely populated during prehistoric times. Connected to these community structures are the prevailing geological conditions in these areas. Both Münsingen-Rain and Monte Bibele are located in a region where homogeneous geological conditions prevail, whereas the landscapes of Nebringen, Radovesice and Kutná Hora are characterised by complex heterogeneous geological conditions. As the majority of individuals in Nebringen and the Czech cemeteries correspond to the expected isotope values for the studied areas, regularly changing land plots might have contributed to the observed variation. Although mass migration as depicted by the historical sources was not observed individual mobility of a small part of these studied communities certainly played a role. Males appeared, thereby, to have slightly more often a non-local birthplace or moved during childhood. Male mobility was, however, not always associated with burial as a warrior. Females, on the other hand, originated more often from the region. Patrilocal residential patterns, with the exception of the Czech cemeteries, were nevertheless not observed. Objects and ideas also seem to have been exchanged freely, as there are no indications that individuals with particular grave goods came from specific areas. It rather appears that the individuals buried with them were either local or had different places of origin. This can be explained by the fact that the exact origin of grave goods is difficult to establish and the occurrence of similar 87Sr/86Sr values in different areas. This study provided important new insights on the period of the “Celtic migrations” and the way of life of these prehistoric people.
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To assess the diagnostic accuracy, image quality, and radiation dose of an iterative reconstruction algorithm compared with a filtered back projection (FBP) algorithm for abdominal computed tomography (CT) at different tube voltages.
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This thesis focuses on “The “great hunting” among the Baka pygmies of the Southeastern Cameroon. A contribution to Anthropology of environment. The problematic in the study is the confrontation of great hunting among the Baka with the institutional, socio-economic and ecological change in forest. The goal is to analyze the mechanisms of adaptation of this game against these changes that affect the Baka environment. The proposed hypothesis suggests that Baka Pygmies have restructured the preparatory ceremonies of the great hunting following changes that occurred in their environmental milieu. Certain ritual animals have been substituted. Hunting lands, tools, methods and periods were also modified. The great hunting is opened to Baka hunters and non Baka hunters. Qualitative techniques, including observation, interviews and focus group discussions were used for data collection. The observations allowed us to understand the reality of driving forces in the forest as well as tools for hunting, hunting land and even the species sought. Interviews and focus group discussions were consolidated data on the ancient practice of hunting for rituals like Jengi and Beka, on the current practice of this hunting and on the impact of the of the modification of this hunting practice on the Baka culture. The results of this research show that the Baka have taken important measure to adapt their great hunting to the changing time and space. But the restructuring of this hunting varies from one village to another. As and when we leave the depths of the forest to the city of Yokadouma the great hunting is practiced less and less. Baka use illegal hunting tools and even fully protected species in their great hunting and in rituals celebrations. The overexploitation of forest resources, the creation of protected areas, full protection of certain large mammals and the action of ecoguards are something of an obstacle to the ancient practice of hunting for ritual. In most of camp where hunting is no more existing, ritual ceremonies are less and less celebrated. The study is divided into five chapters. The first chapter is related to the literature review, the theoretical framework, the definition of concepts, the second focuses on the geographical presentation of the study area, the third chapter looks at factors affecting the great hunting, the fourth chapter deal with the changes observed in the Baka’s great hunting, and the fifth chapter examines consequences of the restriction or suppression of the hunt on the Baka socio culture.
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Khutoretsky dealt with the problem of maximising a linear utility function (MUF) over the set of short-term equilibria in a housing market by reducing it to a linear programming problem, and suggested a combinatorial algorithm for this problem. Two approaches to the market adjustment were considered: the funding of housing construction and the granting of housing allowances. In both cases, locally optimal regulatory measures can be developed using the corresponding dual prices. The optimal effects (with the regulation expenditures restricted by an amount K) can be found using specialised models based on MUF: a model M1 for choice of the optimum structure of investment in housing construction, and a model M2 for optimum distribution of housing allowances. The linear integer optimisation problems corresponding to these models are initially difficult but can be solved after slight modifications of the parameters. In particular, the necessary modification of K does not exceed the maximum construction cost of one dwelling (for M1) or the maximum size of one housing allowance (for M2). The result is particularly useful since slight modification of K is not essential in practice.
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Modification of the ribose unit in DNA and RNA profoundly influences the self-rcognition and the biological properties of the nucleic acids. Conformational restriction of the ribose units, as in LNA and tricyclo-DNA, has been identified as a powerful tool to increase DNA and RNA affinity as well as biological stability and antisense properties. Apart from that sugar modified DNA analogues, as homo-DNA, have shown to be orthogonal base-pairing systems which by virtue of non-crosscommunicating with the natural nucleic acids open novel applications in biotechnology.
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Disturbances in power systems may lead to electromagnetic transient oscillations due to mismatch of mechanical input power and electrical output power. Out-of-step conditions in power system are common after the disturbances where the continuous oscillations do not damp out and the system becomes unstable. Existing out-of-step detection methods are system specific as extensive off-line studies are required for setting of relays. Most of the existing algorithms also require network reduction techniques to apply in multi-machine power systems. To overcome these issues, this research applies Phasor Measurement Unit (PMU) data and Zubov’s approximation stability boundary method, which is a modification of Lyapunov’s direct method, to develop a novel out-of-step detection algorithm. The proposed out-of-step detection algorithm is tested in a Single Machine Infinite Bus system, IEEE 3-machine 9-bus, and IEEE 10-machine 39-bus systems. Simulation results show that the proposed algorithm is capable of detecting out-of-step conditions in multi-machine power systems without using network reduction techniques and a comparative study with an existing blinder method demonstrate that the decision times are faster. The simulation case studies also demonstrate that the proposed algorithm does not depend on power system parameters, hence it avoids the need of extensive off-line system studies as needed in other algorithms.
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Linguistic palaeontology permits the identification of two language families whose linguistic ancestors pose the likeliest candidates for the original domesticators of rice, viz. Hmong-Mien and Austroasiatic. In the 2009 model, the ancient Hmong-Mien was identified as the primary domesticators of Asian rice, and the ancient Austroasiatics as the secondary domesticators. Recent rice genetic research leads to the modification of this model for rice domestication, but falls short of identifying the original locus of rice domestication. At the same time, the precise whereabouts of the Austroasiatic homeland remains disputed. Linguistic evidence unrelated to rice agriculture has been adduced to support a southern homeland for Austroasiatic somewhere within the Bay of Bengal littoral. The implications of new rice genetic research are discussed, the linguistic palaeontological evidence is reassessed, and an enduring problem with the archaeology of rice agriculture is highlighted.