1,676 research outputs found
Geostatistical analysis of an experimental stratigraphy
[1] A high-resolution stratigraphic image of a flume-generated deposit was scaled up to sedimentary basin dimensions where a natural log hydraulic conductivity (ln( K)) was assigned to each pixel on the basis of gray scale and conductivity end-members. The synthetic ln( K) map has mean, variance, and frequency distributions that are comparable to a natural alluvial fan deposit. A geostatistical analysis was conducted on selected regions of this map containing fluvial, fluvial/ floodplain, shoreline, turbidite, and deepwater sedimentary facies. Experimental ln(K) variograms were computed along the major and minor statistical axes and horizontal and vertical coordinate axes. Exponential and power law variogram models were fit to obtain an integral scale and Hausdorff measure, respectively. We conclude that the shape of the experimental variogram depends on the problem size in relation to the size of the local-scale heterogeneity. At a given problem scale, multilevel correlation structure is a result of constructing variogram with data pairs of mixed facies types. In multiscale sedimentary systems, stationary correlation structure may occur at separate scales, each corresponding to a particular hierarchy; the integral scale fitted thus becomes dependent on the problem size. The Hausdorff measure obtained has a range comparable to natural geological deposits. It increases from nonstratified to stratified deposits with an approximate cutoff of 0.15. It also increases as the number of facies incorporated in a problem increases. This implies that fractal characteristic of sedimentary rocks is both depositional process - dependent and problem-scale-dependent
HTC Scientific Computing in a Distributed Cloud Environment
This paper describes the use of a distributed cloud computing system for
high-throughput computing (HTC) scientific applications. The distributed cloud
computing system is composed of a number of separate
Infrastructure-as-a-Service (IaaS) clouds that are utilized in a unified
infrastructure. The distributed cloud has been in production-quality operation
for two years with approximately 500,000 completed jobs where a typical
workload has 500 simultaneous embarrassingly-parallel jobs that run for
approximately 12 hours. We review the design and implementation of the system
which is based on pre-existing components and a number of custom components. We
discuss the operation of the system, and describe our plans for the expansion
to more sites and increased computing capacity
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Exploring content and psychometric validity of newly developed assessment tools for itch and skin pain in atopic dermatitis.
BackgroundAtopic dermatitis (AD) is a common skin disorder characterized by chronic inflammation, altered skin barrier function, and inflammatory cell skin infiltration that decreases health-related quality of life (HRQoL). The study objective was to understand the patient perspective of AD burden and determine suitable patient-reported outcome (PRO) measures.MethodsThis mixed methods study involved the collection of qualitative and quantitative information from adults (≥ 18 years old) and adolescents (12 - 17 years old) with clinician-confirmed AD regarding their experiences of AD symptoms and its impact on HRQoL. The first part of the study included three stages: in-person concept elicitation (CE) interviews, a 2-week daily electronic diary (eDiary) study, and in-person cognitive debriefing (CD) interviews. An Itch numeric rating scale (NRS) (v1.0) and a Skin Pain NRS (v1.0) evaluation during CD interviews required participants to think about their 'worst' itch and 'worst' skin pain in the past 24 h. Other PRO measures allowed for psychometric testing. The second part of the study involved telephone-depth interviews (TDIs) and qualitative feedback from participants who had not participated in the CD interviews. Qualitative data were thematically analyzed. Psychometric evaluation of NRS measures was performed using eDiary data.ResultsIn the CE interviews, itch and/or itching and skin pain were the most prevalent symptoms consistently discussed by participants. Both NRS measures demonstrated strong psychometric reliability and were applicable across ages with suitable concurrent validity. During the CD interviews, some participants focused their answers on their 'average' itch/itching in the past 24 h, rather than their 'worst' itch. Some participants answered the Skin Pain NRS thinking about general pain or other types of pain, rather than skin pain specifically. Consequently, modifications to both measures addressed these issues and re-tested as paper-and-pen versions in subsequent TDIs. Itch NRS (v2.0) modifications helped participants focus on their worst itching. Most participants preferred Skin Pain NRS v2.0b, which included skin pain descriptors.ConclusionsItching and skin pain are the most important and relevant AD symptoms. The Itch NRS (v2.0) and Skin Pain NRS (v2.0b) appear to be appropriate endpoints for the assessment of itching and skin pain severity for clinical trials with adults and adolescents with AD
Ensayo de una metodología innovadora para la detección de masas polimetálicas profundas: modelo geológico y exploración geotérmica preliminares de la Masa Valverde (Huelva).
Se presentan los resultados provisionales de los trabajos iniciales realizados para el Proyecto Innovative Geothermal Methodology to detect deep blind Polymetallic Ore Bodies, financiado por la CE Y co-financiado por DGICYT y organizaciones participantes. Los principales objetivos de este Proyecto son la cuantificación de los efectos térmicos "in situ" de masas polimetálicas profundas a fin de desarrollar nuevos métodos geotérmicos específicos que puedan detectar depósitos no aflorantes. Dichos métodos deberían proporcionar, previsiblemente, un procedimiento rápido y barato para la detección superficial de cuerpos profundos, midiendo perfiles térmicos en sondeos cortos. La exploración geotérmica permite, a diferencia de otros métodos (por ejemplo gravimetría), discriminar anomalías significativas. Para detectar pequeñas anomalías de temperatura (teniendo en cuenta que el efecto térmico decrece rápidamente hacia la superficie), la resolución térmica medida debe ser del orden de O,001ºC. Se han calibrado nuevos termistores muy sensibles en el Laboratoire National d'Essais (LNE) de París para obtener la máxima sensibilidad en el intervalo de temperaturas considerado (lO a 60ºC). Se miden conductividades térmicas sobre testigos con una precisión del 5% y una reproductibilidad del 2%, que permiten determinar las anomalías del gradiente de temperatura relacionadas con las litologías. Para poner a punto el método, se modelizarán las medidas y se compararán con la realidad de cuerpos conocidos, a fin de establecer un modelo fiable y de aplicación general. Esta metodología se ensaya en primer lugar en la MV (Masa Valverde, Huelva), descubierta y reconocida mediante sondeos por la E.N. Adaro, a fin de partir de un modelo suficientemente preciso para la modelización geotérmica. Los trabajos geológicos realizados integran observaciones de campo, examen y desmuestres de testigos de sondeos, geoquímica, geología estructural y estudio de testigos por diversas técnicas como petrografía, microscopía de menas, DRX, MEB, Microsonda Electrónica, etc. A pesar de la profundidad (en torno a los 600 m.l y de la complejidad de la estructura de MV puesta de manifiesto por el presente estudio, los resultados del primer año de investigación geológica -objeto de esta comunicación-, conducen a un modelo provisional que sirve de base a la interpretación de los datos térmicos. Dicho modelo difiere de los anteriormente conocidos en aspectos como: la posición, definición e interpretación de ciertos tramos litológicos; la demostración de muy frecuentes contactos tectónicos acompañados de procesos de deformación dúctil a veces muy intensa; la identificación de fallas o cabalgamientos que definen unidades independientes, entre las cuales los tramos litológicos, incluidos los cuerpos mineralizados, no son correlaciona bies; la estructura del cuerpo mineralizado, caracterizada por una superposición de escamas imbricadas con geometría antiformal, resultado de procesos tectónicos relacionados con la Tectónica de cabalgamientos de la región y recientemente demostrados -ITGE- en la parte española de la FPI (Faja Pirítica Ibérica). Los resultados provisionales arrojan, pues, un resultado coherente desde las diversas perspectivas de trabajo, particularmente por lo que respecta a los modelos geotérmico y geológico - geométrico, y permiten albergar fundadas esperanzas en una rápida puesta a punto del método, para su aplicación en exploración
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Cross-cultural adaptation of instruments assessing breastfeeding determinants: a multi-step approach
Background: Cross-cultural adaptation is a necessary process to effectively use existing instruments in other cultural and language settings. The process of cross-culturally adapting, including translation, of existing instruments is considered a critical set to establishing a meaningful instrument for use in another setting. Using a multi-step approach is considered best practice in achieving cultural and semantic equivalence of the adapted version. We aimed to ensure the content validity of our instruments in the cultural context of KwaZulu-Natal, South Africa. Methods: The Iowa Infant Feeding Attitudes Scale, Breastfeeding Self-Efficacy Scale-Short Form and additional items comprise our consolidated instrument, which was cross-culturally adapted utilizing a multi-step approach during August 2012. Cross-cultural adaptation was achieved through steps to maintain content validity and attain semantic equivalence in the target version. Specifically, Lynn’s recommendation to apply an item-level content validity index score was followed. The revised instrument was translated and back-translated. To ensure semantic equivalence, Brislin’s back-translation approach was utilized followed by the committee review to address any discrepancies that emerged from translation. Results: Our consolidated instrument was adapted to be culturally relevant and translated to yield more reliable and valid results for use in our larger research study to measure infant feeding determinants effectively in our target cultural context. Conclusions: Undertaking rigorous steps to effectively ensure cross-cultural adaptation increases our confidence that the conclusions we make based on our self-report instrument(s) will be stronger. In this way, our aim to achieve strong cross-cultural adaptation of our consolidated instruments was achieved while also providing a clear framework for other researchers choosing to utilize existing instruments for work in other cultural, geographic and population settings
Sparrows can't sing : East End kith and kinship in the 1960s
Sparrows Can’t Sing (1963) was the only feature film directed by
the late and much lamented Joan Littlewood. Set and filmed in
the East End, where she worked for many years, the film deserves
more attention than it has hitherto received. Littlewood’s career
spanned documentary (radio recordings made with Ewan MacColl
in the North of England in the 1930s) to directing for the stage
and the running of the Theatre Royal in London’s Stratford East,
often selecting material which aroused memories in local audiences
(Leach 2006: 142). Many of the actors trained in her Theatre
Workshop subsequently became better known for their appearances
on film and television. Littlewood herself directed hardly any material
for the screen: Sparrows Can’t Sing and a 1964 series of television
commercials for the British Egg Marketing Board, starring Theatre
Workshop’s Avis Bunnage, were rare excursions into an area of practice
which she found constraining and unamenable (Gable 1980: 32).
The hybridity and singularity of Littlewood’s feature may answer,
in some degree, for its subsequent neglect. However, Sparrows Can’t
Sing makes a significant contribution to a group of films made in
Britain in the 1960s which comment generally on changes in the
urban and social fabric. It is especially worthy of consideration,
I shall argue, for the use which Littlewood made of a particular
community’s attitudes – sentimental and critical – to such changes and
for its amalgamation of an attachment to documentary techniques
(recording an aural landscape on location) with a preference for nonnaturalistic
delivery in performance
Gamma Ray Large Area Space Telescope (GLAST) Balloon Flight Data Handling Overview
The GLAST Balloon Flight Engineering Model (BFEM) represents one of 16 towers
that constitute the Large Area Telescope (LAT), a high-energy (>20 MeV)
gamma-ray pair-production telescope being built by an international partnership
of astrophysicists and particle physicists for a satellite launch in 2006. The
prototype tower consists of a Pb/Si pair-conversion tracker (TKR), a CsI
hodoscopic calorimeter (CAL), an anti-coincidence detector (ACD) and an
autonomous data acquisition system (DAQ). The self-triggering capabilities and
performance of the detector elements have been previously characterized using
positron, photon and hadron beams. External target scintillators were placed
above the instrument to act as sources of hadronic showers. This paper provides
a comprehensive description of the BFEM data-reduction process, from receipt of
the flight data from telemetry through event reconstruction and background
rejection cuts. The goals of the ground analysis presented here are to verify
the functioning of the instrument and to validate the reconstruction software
and the background-rejection scheme.Comment: 5 pages, 4 figures, to be published in IEEE Transacations on Nuclear
Science, August 200
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