431 resultados para Coincidence


Relevância:

10.00% 10.00%

Publicador:

Resumo:

The kaon electroproduction reaction H(e, e ′K+)Λ was studied as a function of the four momentum transfer, Q2, for different values of the virtual photon polarization parameter. Electrons and kaons were detected in coincidence in two High Resolution Spectrometers (HRS) at Jefferson Lab. Data were taken at electron beam energies ranging from 3.4006 to 5.7544 GeV. The kaons were identified using combined time of flight information and two Aerogel Čerenkov detectors used for particle identification. For different values of Q2 ranging from 1.90 to 2.35 GeV/c2 the center of mass cross sections for the Λ hyperon were determined for 20 kinematics and the longitudinal, σ L, and transverse, σT, terms were separated using the Rosenbluth separation technique. ^ Comparisons between available models and data have been studied. The comparison supports the t-channel dominance behavior for kaon electroproduction. All models seem to underpredict the transverse cross section. An estimate of the kaon form factor has been explored by determining the sensitivity of the separated cross sections to variations of the kaon EM form factor. From comparison between models and data we can conclude that interpreting the data using the Regge model is quite sensitive to a particular choice for the EM form factors. The data from the E98-108 experiment extends the range of the available kaon electroproduction cross section data to an unexplored region of Q2 where no separations have ever been performed. ^

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Caffeine is the most consumed psychostimulant, with effects on attention, memory, and arousal. But when this substance is ingested near to bedtime there is a decrease on sleep, interfering on mnemonic processes. So, our ain was to investigate how the caffeine ingested near to sleep onset acts on sleep and memory in marmosets. We used 16 adult marmosets, single housed, in a 12:12h light-dark cycle. For registering locomotor activity were used two kinds of sensors. The gyroscope sensor registers activity each 30 sec and detects motion with good accuracy. Because of this we used this sensor for detecting nocturnal activity. The second sensor was based on infrared and accumulates activity each 5 min and it’s not able to detect nocturnal activity, just diurnal activity. We also used camera for registering Rest phase of one marmoset. For the cognitive task, the animals needed to learn a rewarded context (CR) when compared to a non-rewarded context CNR). This experiment comprises 5 phases: 1) Two days of habituation to apparatus; 2)Training for 8 days; 3) oral administration of caffeine (10 mg/kg) or placebo administration ±1h before sleep onset, for 8 days, with marmosets receiving placebo or caffeine; 4) retraining to apparatus and after that, placebo administration (placebo group-GP), or caffeine administration (with continuous group-GC and acute groupGA); 5) Test, for evaluating learning to CR. The sessions were filmed and each one had 8 min of duration. At 7 am started the habituation, training and test sessions, and at 3:15 pm started retraining. The results for gyroscope sensor showed that there was coincidence of 68,57% with nocturnal register of the cameras. Then, the gyroscope sensors detected nocturnal activity for all experimental groups Moreover, when compared sensor gyroscope with sensor based on infrared, was observed that both sensor presented similarity on patterns of activity curve. When we observed the effects of caffeine on Activity-Rest Cycle in GP, GA and GC, is possible to see that that gyroscope sensors and based on infrared presented only intra group differences. As behavioral results, the marmosets learned to discriminate CR when compared to CNR. Moreover, GP presented deficits on memory recall during the test, and GA increased the memory recall, when both were compared to GP. We concluded that the marmosets were able to learning the cognitive task and that the caffeine ingested near to sleep onset acts modulating memory in these animals. Moreover the gyroscope sensor can be used as alternative tool for investigating nocturnal activity. Then, the utilization of this non-invasive device allows marmosets exhibit their behavior within the laboratory conditions as natural as possible.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This thesis investigates materialization strategies of non-assumption of enunciation responsibility and inscription of an authorial voice in scientific articles produced by initial researchers in Linguistics. The specific focus lays on identify, describe and interpret: i) linguistics marks that assign enunciation responsibility; ii) the positions taken by the first speaker-enunciator (L1/E1) in relation to points of view (PoV) imputed to second enunciators (e2); and iii) the linguistic marks that assign the formulation of themselves' PoV. As a practical deployment, it is proposed to discuss how to teach taking into account text discursive strategies regarding to enunciation responsibility and also authorship in academic and scientific texts. Our research corpus is formed by eight scientific essays and they were selected in a renamed Linguistics scientific magazine which is high evaluated by Qualis/CAPES (Brazil Science Agency). The methodology follows the assumptions of a qualitative research, and an it has such an interpretative basis, even though it takes support in a quantitative approach, too. Theoretically, we based this research on Textual Analysis of Speech and linguistics theories about linguistic enunciation area. The results show two kinds of movements in PoV management: imputation and responsibility. In imputation contexts, the most recursive linguistic marks were reported speech, indirect speech, reported speech with “that”, modalization in reported speech (in enunciation with “according to”, “in agreement with”, “for”), beyond that we see certain points of non-coincidences of speech, specifically the non-coincidence of the speech itself. The way those linguistic marks occur in the text point out three kinds of enunciation positions that are assumed by L1/E1 in relation to PoV of e2: agreement, disagreement and a pseudo neutrality. It was clearly recursive the imputation followed by agreement (explicit or not), this perspective puts other’s voices to defend a speech assumed like own authorship. In speech responsibility contexts, we observed such a formulation of inner PoV that results from theoretical findings undertaken by novice researchers (revealing how he/she interpreted concepts of the theory) or arising from their research data, allowing them to express with more autonomy and without reporting to speeches from e2. Based on those data, we can say that, in text by initial researchers, the authorship is strongly built upon PoV and also dependent from others' words (theory and the scholars quoted there), taking into account that many contexts in which we can observe agreement position, PoV formulations with words taken from e2 and assumed as own words by syntactic integration, the comments about what the other says, the absence of explanations and additions, as well as a data analysis that could show agreement with the theory used to support the work. These results allow us to visualize how initial researcher dialogs with the theoretical enunciation sources he or she takes as support and how he/she displays the status of a subject doing a research and positioning himself/herself as a researcher/author in the scientific field. In assuming the reported speech, when quoting, as a resource that allows the enunciation responsibility and also when doing evidence to the positions of speaker-enunciator in relation do reported PoV, this suggests to a textual-discursive treatment of quoting in academic and scientific text, in a context of teaching that gives attention to the development of communication skills of initial researcher and that can contribute to insert and interact students in the scientific field.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This thesis investigates materialization strategies of non-assumption of enunciation responsibility and inscription of an authorial voice in scientific articles produced by initial researchers in Linguistics. The specific focus lays on identify, describe and interpret: i) linguistics marks that assign enunciation responsibility; ii) the positions taken by the first speaker-enunciator (L1/E1) in relation to points of view (PoV) imputed to second enunciators (e2); and iii) the linguistic marks that assign the formulation of themselves' PoV. As a practical deployment, it is proposed to discuss how to teach taking into account text discursive strategies regarding to enunciation responsibility and also authorship in academic and scientific texts. Our research corpus is formed by eight scientific essays and they were selected in a renamed Linguistics scientific magazine which is high evaluated by Qualis/CAPES (Brazil Science Agency). The methodology follows the assumptions of a qualitative research, and an it has such an interpretative basis, even though it takes support in a quantitative approach, too. Theoretically, we based this research on Textual Analysis of Speech and linguistics theories about linguistic enunciation area. The results show two kinds of movements in PoV management: imputation and responsibility. In imputation contexts, the most recursive linguistic marks were reported speech, indirect speech, reported speech with “that”, modalization in reported speech (in enunciation with “according to”, “in agreement with”, “for”), beyond that we see certain points of non-coincidences of speech, specifically the non-coincidence of the speech itself. The way those linguistic marks occur in the text point out three kinds of enunciation positions that are assumed by L1/E1 in relation to PoV of e2: agreement, disagreement and a pseudo neutrality. It was clearly recursive the imputation followed by agreement (explicit or not), this perspective puts other’s voices to defend a speech assumed like own authorship. In speech responsibility contexts, we observed such a formulation of inner PoV that results from theoretical findings undertaken by novice researchers (revealing how he/she interpreted concepts of the theory) or arising from their research data, allowing them to express with more autonomy and without reporting to speeches from e2. Based on those data, we can say that, in text by initial researchers, the authorship is strongly built upon PoV and also dependent from others' words (theory and the scholars quoted there), taking into account that many contexts in which we can observe agreement position, PoV formulations with words taken from e2 and assumed as own words by syntactic integration, the comments about what the other says, the absence of explanations and additions, as well as a data analysis that could show agreement with the theory used to support the work. These results allow us to visualize how initial researcher dialogs with the theoretical enunciation sources he or she takes as support and how he/she displays the status of a subject doing a research and positioning himself/herself as a researcher/author in the scientific field. In assuming the reported speech, when quoting, as a resource that allows the enunciation responsibility and also when doing evidence to the positions of speaker-enunciator in relation do reported PoV, this suggests to a textual-discursive treatment of quoting in academic and scientific text, in a context of teaching that gives attention to the development of communication skills of initial researcher and that can contribute to insert and interact students in the scientific field.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs "radio-hybrid" measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluorescence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request. (C) 2011 Elsevier B.V. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

1. nowhere landscape, for clarinets, trombones, percussion, violins, and electronics

nowhere landscape is an eighty-minute work for nine performers, composed of acoustic and electronic sounds. Its fifteen movements invoke a variety of listening strategies, using slow change, stasis, layering, coincidence, and silence to draw attention to the sonic effects of the environment—inside the concert hall as well as the world outside of it. The work incorporates a unique stage set-up: the audience sits in close proximity to the instruments, facing in one of four different directions, while the musicians play from a number of constantly-shifting locations, including in front of, next to, and behind the audience.

Much of nowhere landscape’s material is derived from a collection of field recordings

made by the composer during a road trip from Springfield, MA to Douglas, WY along US- 20, a cross-country route made effectively obsolete by the completion of I-90 in the mid- 20th century. In an homage to artist Ed Ruscha’s 1963 book Twentysix Gasoline Stations, the composer made twenty-six recordings at gas stations along US-20. Many of the movements of nowhere landscape examine the musical potential of these captured soundscapes: familiar and anonymous, yet filled with poignancy and poetic possibility.

2. “The Map and the Territory: Documenting David Dunn’s Sky Drift”

In 1977, David Dunn recruited twenty-six musicians to play his work Sky Drift in the

Anza-Borrego Desert in Southern California. This outdoor performance was documented with photos and recorded with four stationary microphones to tape. A year later, Dunn presented the work in New York City as a “performance/documentation,” playing back the audio recording and projecting slides. In this paper I examine the consequences of this kind of act: what does it mean for a recording of an outdoor work to be shared at an indoor concert event? Can such a complex and interactive experience be successfully flattened into some kind of re-playable documentation? What can a recording capture and what must it exclude?

This paper engages with these questions as they relate to David Dunn’s Sky Drift and to similar works by Karlheinz Stockhausen and John Luther Adams. These case-studies demonstrate different solutions to the difficulty of documenting outdoor performances. Because this music is often heard from a variety of equally-valid perspectives—and because any single microphone only captures sound from one of these perspectives—the physical set-up of these kind of pieces complicate what it means to even “hear the music” at all. To this end, I discuss issues around the “work itself” and “aura” as well as “transparency” and “liveness” in recorded sound, bringing in thoughts and ideas from Walter Benjamin, Howard Becker, Joshua Glasgow, and others. In addition, the artist Robert Irwin and the composer Barry Truax have written about the conceptual distinctions between “the work” and “not- the-work”; these distinctions are complicated by documentation and recording. Without the context, the being-there, the music is stripped of much of its ability to communicate meaning.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Head motion during a Positron Emission Tomography (PET) brain scan can considerably degrade image quality. External motion-tracking devices have proven successful in minimizing this effect, but the associated time, maintenance, and workflow changes inhibit their widespread clinical use. List-mode PET acquisition allows for the retroactive analysis of coincidence events on any time scale throughout a scan, and therefore potentially offers a data-driven motion detection and characterization technique. An algorithm was developed to parse list-mode data, divide the full acquisition into short scan intervals, and calculate the line-of-response (LOR) midpoint average for each interval. These LOR midpoint averages, known as “radioactivity centroids,” were presumed to represent the center of the radioactivity distribution in the scanner, and it was thought that changes in this metric over time would correspond to intra-scan motion.

Several scans were taken of the 3D Hoffman brain phantom on a GE Discovery IQ PET/CT scanner to test the ability of the radioactivity to indicate intra-scan motion. Each scan incrementally surveyed motion in a different degree of freedom (2 translational and 2 rotational). The radioactivity centroids calculated from these scans correlated linearly to phantom positions/orientations. Centroid measurements over 1-second intervals performed on scans with ~1mCi of activity in the center of the field of view had standard deviations of 0.026 cm in the x- and y-dimensions and 0.020 cm in the z-dimension, which demonstrates high precision and repeatability in this metric. Radioactivity centroids are thus shown to successfully represent discrete motions on the submillimeter scale. It is also shown that while the radioactivity centroid can precisely indicate the amount of motion during an acquisition, it fails to distinguish what type of motion occurred.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Partiendo de la hipótesis de que el patrón común que vincula a las distintas bibliotecas de la Universidad Nacional de La Plata (UNLP) para la construcción de la signatura de clase es el uso de la Clasificación Decimal Universal (CDU), y que existe una dispersión importante en los elementos que componen la signatura librística, se realizó un relevamiento en las bibliotecas universitarias para indagar sobre las formas en que se construye la signatura topográfica para el ordenamiento del material bibliográfico en el estante. Se tomó una muestra de signaturas topográficas del catálogo colectivo Roble. Se analizaron las diferencias y semejanzas encontradas. Se entrevistó a los responsables de los procesos técnicos de cada biblioteca para indagar sobre las causas de las diferencias encontradas. Se comprobó que, si bien la mayoría de las bibliotecas usan CDU para formar la signatura de clase, emplean ediciones diferentes con criterios de uso disímiles. Además, en la formación de la signatura librística, los criterios empleados varían notablemente de una biblioteca a otra, haciendo aún más difícil la coincidencia de signaturas topográficas asignadas. Se concluye que el factor determinante en el resultado es la forma en que se desarrollan las prácticas laborales dentro de estas instituciones.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Partiendo de la hipótesis de que el patrón común que vincula a las distintas bibliotecas de la Universidad Nacional de La Plata (UNLP) para la construcción de la signatura de clase es el uso de la Clasificación Decimal Universal (CDU), y que existe una dispersión importante en los elementos que componen la signatura librística, se realizó un relevamiento en las bibliotecas universitarias para indagar sobre las formas en que se construye la signatura topográfica para el ordenamiento del material bibliográfico en el estante. Se tomó una muestra de signaturas topográficas del catálogo colectivo Roble. Se analizaron las diferencias y semejanzas encontradas. Se entrevistó a los responsables de los procesos técnicos de cada biblioteca para indagar sobre las causas de las diferencias encontradas. Se comprobó que, si bien la mayoría de las bibliotecas usan CDU para formar la signatura de clase, emplean ediciones diferentes con criterios de uso disímiles. Además, en la formación de la signatura librística, los criterios empleados varían notablemente de una biblioteca a otra, haciendo aún más difícil la coincidencia de signaturas topográficas asignadas. Se concluye que el factor determinante en el resultado es la forma en que se desarrollan las prácticas laborales dentro de estas instituciones.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Partiendo de la hipótesis de que el patrón común que vincula a las distintas bibliotecas de la Universidad Nacional de La Plata (UNLP) para la construcción de la signatura de clase es el uso de la Clasificación Decimal Universal (CDU), y que existe una dispersión importante en los elementos que componen la signatura librística, se realizó un relevamiento en las bibliotecas universitarias para indagar sobre las formas en que se construye la signatura topográfica para el ordenamiento del material bibliográfico en el estante. Se tomó una muestra de signaturas topográficas del catálogo colectivo Roble. Se analizaron las diferencias y semejanzas encontradas. Se entrevistó a los responsables de los procesos técnicos de cada biblioteca para indagar sobre las causas de las diferencias encontradas. Se comprobó que, si bien la mayoría de las bibliotecas usan CDU para formar la signatura de clase, emplean ediciones diferentes con criterios de uso disímiles. Además, en la formación de la signatura librística, los criterios empleados varían notablemente de una biblioteca a otra, haciendo aún más difícil la coincidencia de signaturas topográficas asignadas. Se concluye que el factor determinante en el resultado es la forma en que se desarrollan las prácticas laborales dentro de estas instituciones.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The High Nutrient Low Chlorophyll (HNLC) Southern Ocean plays a key role in regulating the biological pump and the global carbon cycle. Here we examine the efficacy of stable cadmium (Cd) isotope fractionation for detecting differences in biological productivity between regions. Our results show strong meridional Cd isotope and concentration gradients modulated by the Antarctic Fronts, with a clear biogeochemical divide located near 56°S. The coincidence of the Cd isotope divide with the Southern Boundary of the Antarctic Circumpolar Current (ACC),together with evidence for northward advection of the Cd signal in the ACC, demonstrate that Cd isotopes trace surface ocean circulation regimes. The relationships between Cd isotope ratios and concentrations display two negative correlations, separating the ACC and Weddell Gyre into two distinct Cd isoscapes. These arrays are consistent with Rayleigh fractionation and imply a doubling of the isotope effect due to biological consumption of Cd during water transport from the Weddell Gyre into the ACC. The increase in magnitude of Cd isotope fractionation can be accounted for by differences in the phytoplankton biomass, community composition, and their physiological uptake mechanisms in the Weddell Gyre and ACC, thus linking Cd isotope fractionation to primary production and the global carbon cycle.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Cuttings of Lower and Middle Keuper sediments of the INFLUINS-drilling in the central Thuringian Syncline were geochemically analysed. Indications about shifting depositional environments are interpreted from ratios of whole-rock element contents. For the middle part of sandstone cycle S 2 high heavy metal contents imply precipitation of sufidic ores during a short marine interval. Element contents are compared with potential source rocks in the southern part of the Baltic Shield, in the Lausitz Anticline Zone, in the Erzgebirge, in the moldanubian part, in the broad sense, of the Bohemian Massif, in the Münchberg Gneiss Massif and the Fichtelgebirge. The geochemical coincidence of investigated Keuper sediments is highest with grantioid and gabbroic rocks of southern Scandinavia. Granodiorite rocks of the Lausitz are also possible sources, whereas granites of the Fichtelgebirge and the Bohemian Massif are less probable.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Holocene sediment record of Lake Tiefer See exhibits striking alternations between well-varved and non-varved intervals. Here we present a high resolution multi-proxy record for the past ~6000 years and discuss possible causes for the observed sediment variability. This approach comprises of microfacies, geochemical and microfossil analyses as well as of a multiple dating concept including varve counting, tephrochronology and radiocarbon dating. Four periods of predominantly well-varved sediment were identified at 6000-3950 cal. a BP, 3100-2850 cal. a BP, 2100-750 cal. a BP and AD 1924-present. Except of sub-recent varve formation, these periods are considered to reflect reduced lake circulation and consequently, stronger anoxic bottom water conditions. In contrast, intercalated intervals of poor varve preservation or even extensively mixed non-varved sediments indicate strengthened lake circulation. Sub-recent varve formation since AD 1924 is, in addition to natural forcing, influenced by enhanced lake productivity due to modern anthropogenic eutrophication. The general increase in periods of intensified lake circulation in Lake Tiefer See since ~4000 cal. a BP presumably is caused by gradual changes in Northern Hemisphere orbital forcing, leading to cooler and windier conditions in Central Europe. Superimposed decadal to centennial scale variability of the lake circulation regime likely is the result of additional human-induced changes of the catchment vegetation. The coincidence of major non-varved periods at Lake Tiefer See and intervals of bioturbated sediments in the Baltic Sea implies a broader regional significance of our findings.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Hydrogenous manganese nodules form on the ocean floor by slow authigenic precipitation (1-6 mm/Ma) of the oxyhydroxides of manganese and iron that continuously scavenge trace elements from the marine environment. Consequently, these nodules represent independent marine deposits useful for the study of the chemical signatures of the paleomarine environments. The results presented are a continuation of a study of the Zetes-3D nodule from the Pacific Ocean. It is a large (24x17x10 cm) hydrogenous nodule whose slow growth rate of 1.3 mm/Ma was detremined using 10Be techniques. A positive cerium anomaly is observed throughout the nodule and its Ir content indicates a sharp spike at 54-62 Ma in fair agreement with the K-T event.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The present paper analyses the parallelism existing between academic and professional discourse regarding three interrelated subjects: journalists´ training needs, their adaptation to multimedia profile changes and recognition of University graduates via professional regulation. This study relies on a bibliographical review and brings together the opinion of five professional groups by means of an interview using an openended questionnaire. The results show a coincidence in both discourses regarding the need for firmly grounded training of the journalists with study plans which integrate the new profiles. At the same time, it reflects the discrepancy of the journalistic groups with regard to professional regulation based on the University degree, whose vindication does not appear to be a priority in academic circles.