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Jornais Acesso aberto

Guy Brett, Gwen Nuttall, Dinah Morrison, Nicholas Fairbairn, Jabbo Smith, Boris Schapiro, Ian Marter, Carol Price, Patricia Jones, Victor Bryant, Michael Binyon, John Whale, Judi Dench, Alison Miller, George Perry, Andrew Stephen,

... rock opera The Russian rock opera June and Avos will be broadcast on Wednesday (9.00-10. ...

1983 - Gale Group | Sunday Times HA GDA

Artigo Revisado por pares

I. Bartov,

... combined effect of the growth promoters (GPs) avoparcin (AVO, 20 mg/kg), Zn bacitracin (BAC, 25 mg/ ... 1) and the effect of age of feeding AVO (experiment 2) on performance, utilisation of dietary nutrients, ... carcases (DEC) and size of various organs. 2. AVO, in contrast to BAC and NIT, significantly (P< ... dietary AMEn content, weight gain and food efficiency. AVO also significantly decreased the size of the liver ... the SI was less pronounced than that of AVO. Although the effect of AVO on increasing fat retention, growth and food efficiency ...

Tópico(s): Meat and Animal Product Quality

1992 - Taylor & Francis | British Poultry Science

Artigo Revisado por pares

Christopher P. Ross,

... depositional settings. While exploration groups tend to use AVO attributes for detection and risk quantification, exploitation and production groups use AVO attributes for reservoir characterization and even fluid-front ... reservoir. This paper focuses on the accuracy of AVO attributes commonly used in reservoir characterization. In particular, ... mu-rho λ-μ-ρ), and elastic impedance AVO attributes, and their ability to accurately predict reservoir extent are presented. Derivative AVO attribute volumes that are caliabrated to well data ...

Tópico(s): Hydraulic Fracturing and Reservoir Analysis

2002 - Society of Exploration Geophysicists | The Leading Edge

Artigo Revisado por pares

Feng Shen, Xiang Zhu, M. Nafi Toksöz,

... distortions induced by geology‐related influences on azimuthal AVO responses. In the presence of vertically aligned fractures, ... v) , and γ (v) ), NMO velocities, and azimuthal AVO responses, where δ (v) is responsible for near‐ ... finite‐difference modeling show that P‐wave azimuthal AVO variations do not necessarily correlate with the magnitude ... rocks have an effect on P‐wave azimuthal AVO variations. Varying the saturated fluid content of fractures can lead to azimuthal AVO variations and may greatly change azimuthal AVO responses. ...

Tópico(s): Geophysical Methods and Applications

2002 - Society of Exploration Geophysicists | Geophysics

Artigo Acesso aberto Brasil Produção Nacional Revisado por pares

Cristina Maria de Souza Brito Dias, Márcia Andréa Souza e Silva,

... a percepção dos jovens adultos acerca dos seus avós. Dela participaram 100 universitários (50 de cada sexo), ... resultados são: Os significados mais importantes representados pelos avós foram os de "respeito" e "sabedoria e experiência de vida. O(a) avô(a) preferido pelos netos foi a "avó materna". O motivo da preferência foi a convivência maior. Quanto à contribuição dada pelos avós à família destacaram-se "a educação dada aos ... netos". A diferença entre os pais e os avós, na opinião dos jovens, foi "a diferença de ...

Tópico(s): Child Welfare and Adoption

2003 - UNIVERSIDADE ESTADUAL DE MARINGÁ | Psicologia em Estudo

Artigo Revisado por pares

J. P. Blangy,

The amplitude variation with offset (AVO) responses of elastic transversely isotropic media are sensitive to contrasts in both of Thomsen’s anisotropic parameters δ and ε. The ... the greater the effects of anisotropy on the AVO signature. Contrasts in δ are most important under ... degrees and beyond). Consequently, using Rutherford and Williams’ AVO classification of isotropic gas sands, type I gas ... isotropic (TI) shale exhibit a larger decrease in AVO than if the shale had been isotropic, and ... isotropic (TI) shale exhibit a larger increase in AVO than if the shale had been isotropic. Furthermore, ...

Tópico(s): Seismic Waves and Analysis

1994 - Society of Exploration Geophysicists | Geophysics

Artigo Acesso aberto Brasil Produção Nacional Revisado por pares

Alessandra Ribeiro Ventura Oliveira, Lucy Gomes Vianna, Carmen Jansen de Cárdenas,

... social quanto no familiar. Aumentaram o número de avós e o número de anos que as pessoas vivem como avós. A avosidade, definida como laço de parentesco, está ... objetivo deste trabalho foi avaliar a relação entre avós e netos no período da infância, de acordo com a percepção de avós e de seus netos. Foram realizadas 17 entrevistas semiestruturadas com avós e seus netos. Os resultados foram analisados e ... revelou presença significativa de intergeracionalidade na visão das avós, representada pelas palavras mais frequentes em ordem decrescente: ...

Tópico(s): Intergenerational Family Dynamics and Caregiving

2010 - UNIVERSIDADE FEDERAL DO RIO DE JANEIRO | Revista Brasileira de Geriatria e Gerontologia

Artigo Revisado por pares

Lee Hunt, Jon Downton, Scott Reynolds, Scott Hadley, Daniel Trad, Mark Hadley,

... prestack interpolation prior to prestack migration to improve AVO analysis on image gathers is demonstrated on an ... interpolation achieves this improvement by reducing migration artifacts. AVO analysis attempts to estimate fundamental information from surface ... noise, which is a material cause of inaccurate AVO estimates. Prestack 5D interpolation is applied prior to prestack migration and AVO analysis on the imaged gathers to address this ... algorithm includes offset and azimuth dimensions that preserve AVO information. This method is evaluated bycomparing the results ...

Tópico(s): Drilling and Well Engineering

2010 - Society of Exploration Geophysicists | Geophysics

Artigo Revisado por pares

E. Causse, M. Riede, A. van Wijngaarden, A. Buland, J. F. Dutzer, Richard Fillon,

AVO analysis can be conducted by estimating amplitude variation with offset (AVO) attributes from seismic prestack data and by characterizing ... projection in the attribute space. The most common AVO attributes are the intercept (zero-offset reflectivity) and AVO gradient. We have constructed an optimized, model-based linear AVO equation that is more accurate than usual AVO approximations. The parameters of this equation represent new AVO attributes that are more directly related to the ... in seismic reflection amplitudes. We use these new AVO attributes to classify reflector responses from field data. ...

Tópico(s): Hydraulic Fracturing and Reservoir Analysis

2007 - Society of Exploration Geophysicists | Geophysics

Artigo Acesso aberto Revisado por pares

Aaron Wandler, Brian Evans, Curtis A. Link,

... lapse changes in seismic amplitude variation with offset (AVO) from a reservoir can be used to optimize ... a scaled physical model experiment to study the AVO response of mixtures of brine, oil, and carbon ... lie within the error of the experiment. However, AVO analysis was able to detect changes in the ... oil and those that did not. When the AVO response was plotted in the AVO intercept-gradient domain, fluids containing oil were clearly ... not containing oil. This was observed in the AVO response from both the top and base of ...

Tópico(s): Hydraulic Fracturing and Reservoir Analysis

2007 - Society of Exploration Geophysicists | Geophysics

Artigo Acesso aberto Brasil Produção Nacional Revisado por pares

Caroline Dal Ri Kipper, Rita de Cássia Sobreira Lopes,

O tornar-se avó assinala um período de transição no ciclo de vida familiar, marcado por transformações psíquicas significativas para os avós, caracterizando a quarta individuação. Este trabalho teve como objetivo investigar a experiência de tornar-se avó e sua importância no processo de individuação. Foi utilizado delineamento de estudo de caso coletivo. Onze avós maternas, com idades entre 49 e 66 anos, ... responderam a uma entrevista semi-estruturada. Todas as avós tinham tido seus primeiros netos e a entrevista ...

Tópico(s): Child Welfare and Adoption

2006 - UNIVERSIDADE DE BRASÍLIA | Psicologia Teoria e Pesquisa

Artigo Revisado por pares

Suping Peng, Chen Hua-jing, Ruizhao Yang, Yunfeng Gao, Chen Xin-ping,

... and differences in employing amplitude variation with offset (AVO) to explore for gas-sand reservoirs, as opposed ... that large Poisson’s ratio contrasts, resulting in AVO gradient anomalies, are expected for both kinds of ... top of gas sands usually has a negative AVO gradient, leading to a class one, two, or ... top of a CBM reservoir has a positive AVO gradient, leading to a class four anomaly. Three environmental factors may limit the usage of AVO for CBM reservoirs: the smaller contrast in Poisson’ ... However, other factors work in favor of using AVO. The strikingly high reflection amplitude of coal improves ...

Tópico(s): Geophysical Methods and Applications

2006 - Society of Exploration Geophysicists | Geophysics

Artigo Revisado por pares

Charles C. Mosher, Timothy H. Keho, Arthur B. Weglein, Douglas J. Foster,

Amplitude variation with offset (AVO) analysis is often limited to areas where multidimensional propagation effects such as reflector dip and diffractions from faults can be ... migration, the prestack migrated data are used in AVO analysis or other inversion techniques to infer local ... improving the lateral resolution and spatial positioning of AVO anomalies. In this approach, a plane‐wave decomposition ... preserve amplitude as a function of angle. Normal AVO analysis is then applied to the prestack migrated ...

Tópico(s): Hydraulic Fracturing and Reservoir Analysis

1996 - Society of Exploration Geophysicists | Geophysics

Artigo Acesso aberto

Ayman Saleh, Ahmad Aljada, Syed A. A. Rizvi, Amre Nasr, Ahmed Alaskar, Jack D. Williams,

... toxicity of the plant extracted oil from buds (AVO-b) and leaves (AVO-l) and characterized their growth inhibitory effects on cancer cells. AVO-b and AVO-l from A. vulgaris L. were extracted by ... action on HL-60 cells. Low concentrations of AVO-b and AVO-l inhibited the growth of HL-60 cells ... Apaf-1 and XIAP. Interestingly, low doses of AVO-b and AVO-1 also induced apoptosis in various cancer cell ... to activate the caspase cascade. The finding that AVO-b and AVO-l are more efficient to induce apoptosis in ...

Tópico(s): Natural Compounds in Disease Treatment

2014 - BioMed Central | BMC Complementary and Alternative Medicine

Artigo Revisado por pares

Michael R. Gold, Yinghong Yu, G. André Ng, Kenneth M. Steín, Ulrika Birgersdotter‐Green, Timothy E. Meyer, Milan Seth, Kenneth A. Ellenbogen,

Background The role of atrioventricular optimization (AVO) for cardiac resynchronization therapy (CRT) is controversial. Identifying subgroups that benefit from optimization is important to improve CRT outcomes. Pacing at sites ... ventricular (LV) electrical delay increases the effectiveness of AVO. Methods This substudy of the SMART-AV trial ... who were randomized to either an electrogram-based AVO (SmartDelay) or nominal atrioventricular delay (120 ms). The ... for the entire cohort. Moreover, the benefit of AVO increased as QLV prolonged. At the longest QLV ...

Tópico(s): Neuroscience and Neural Engineering

2013 - Elsevier BV | Heart Rhythm

Artigo Acesso aberto Revisado por pares

Ilya Tsvankin,

... influence of anisotropy on amplitude variation with offset (AVO) analysis is not limited to reflection coefficients. AVO signatures (e.g., AVO gradient) in anisotropic media are also distorted by ... typical of sand‐shale sequences commonly encountered in AVO analysis. Here, I examine the influence of P‐ and S‐wave radiation patterns on AVO in the most common anisotropic model—transversely isotropic ... of the distortions of the radiation patterns on AVO results. It is shown that the shape of ... in the range of angles most important to AVO analysis (0–40°) is primarily dependent on the ...

Tópico(s): Geophysics and Sensor Technology

1995 - Society of Exploration Geophysicists | Geophysics

Artigo Revisado por pares

Luc T. Ikelle, Lasse Amundsen,

We analyze amplitude variations with offsets and azimuths (AVO-A) of an anisotropic half-space bounded by ... SH. When the overburden is assumed isotropic, the AVO-A of each of these three scattering modes ... that describe the seismic amplitude variations with offsets (AVO) for a given azimuth. The forms of AVO functions are similar to those of classical AVO formulae; for instance, the AVO functions corresponding to the P–P scattering mode ... reflectors. One of the benefits of describing the AVO-A as a Fourier series is that the ...

Tópico(s): Drilling and Well Engineering

2001 - Elsevier BV | Journal of Applied Geophysics

Artigo Revisado por pares

Per Avseth, Andre Janke, F. Horn,

AVO inversion of prestack seismic data, constrained by geologic knowledge and rock-physics modeling, is an essential ... this study, we demonstrate the use of simultaneous AVO inversion in an area of the Norwegian Sea where several proven discoveries with strong AVO anomalies are present, all of which are structural ... high correctly predicted the presence of hydrocarbons. The AVO inversion also gave support for a stratigraphic trap ... out to be a failure, as the observed AVO anomaly was false. Postdrill analysis showed that a ...

Tópico(s): Drilling and Well Engineering

2016 - Society of Exploration Geophysicists | The Leading Edge

Artigo Revisado por pares

John P. Castagna, Herbert W. Swan, Douglas J. Foster,

Amplitude variation with offset (AVO) interpretation may be facilitated by crossplotting the AVO intercept (A) and gradient (B). Under a variety of reasonable petrophysical assumptions, ... large reflection coefficients may exhibit large increases in AVO. Deviations from the background trend may be indicative ... offset, gas sands may exhibit a variety of AVO behaviors. A classification of gas sands based on ... sands fall in quadrant III and have negative AVO intercept and gradient. These sands exhibit the amplitude ...

Tópico(s): Hydraulic Fracturing and Reservoir Analysis

1998 - Society of Exploration Geophysicists | Geophysics

Artigo

E. S. ISAACSON, Dennis B. Neff,

Recent amplitude versus offset (AVO) interpretations in the Norwegian Barents Sea and offshore West Greenland have identified subtle and complex anomalies which are best interpreted ... gradient cross plot analysis scheme. The creation of AVO intercept (A) and gradient (B) seismic sections allows ... information concerning the geological framework that created the AVO response. Determination of the background trend on an A versus B cross plot is problematic in AVO analysis since variations in lithology and depth are ...

Tópico(s): Hydraulic Fracturing and Reservoir Analysis

1999 - Zoological Society of London | Geological Society London Petroleum Geology Conference series

Artigo Revisado por pares

David L. Compton, John R. Goodell, Kervin O. Evans, Debra E. Palmquist,

... regions. The most commonly used compounds are avobenzone (AVO, λ max 356 nm) and octinoxate (ONX, λ ... 328 nm, approximately the median λ max of AVO and ONX. Equimolar mixtures of AVO–ONX and AVO–FSG, 50 μM:50 μM, solutions in ethanol ... to UV radiation. While it was determined that AVO–FSG mixtures possessed statistically indistinguishable total absorbance capacity compared to AVO–ONX solutions, AVO–FSG possessed slightly better photostability after 4 hours ... e.g., 50 μM:25 μM:25 μM AVO–ONX–FSG) resulted in the best mixture with ...

Tópico(s): Skin Protection and Aging

2018 - Wiley | Journal of the American Oil Chemists Society

Artigo Acesso aberto Revisado por pares

Tsara Kamilah Ridwan, Maman Hermana, Luluan Almanna Lubis, Zaky Ahmad Riyadi,

Amplitude versus offset (AVO) analysis integration to well log analysis is considered one of the advanced techniques to improve the understanding of facies and fluid analysis. Generating AVO attributes are one solution to give an accurate ... scale of quality factor of S-wave (SQs) AVO attributes for facies and fluid types separation in ... less ambiguity. SQp and SQs are the new AVO attributes, which derived from AVO analysis and created according to the intercept product ( ... in determining facies and hydrocarbon. SQp and SQs AVO attributes are integrated with well log data and ...

Tópico(s): Geological and Geophysical Studies

2020 - Multidisciplinary Digital Publishing Institute | Applied Sciences

Artigo Revisado por pares

Xiangrong Ma, Rui Dang, Ning Yang, Xiao Li, Ya Zhang, Ying Gong, Zhipan Liu, Wei Guo, Yuanyuan Zhang, Chunyan Li,

... atoms were anchored on the surface of Ag3VO4 (AVO) as a cocatalyst, and the resultant composite photocatalyst ... water driven by visible light. The as-prepared AVO particles are hollow nanospheres in the monoclinic phase ... 2.20 eV. The light absorption edge of AVO/Pt is slightly red-shifted compared to that of the pristine AVO, indicating more visible light absorption of AVO/Pt. The XPS peaks of Ag, V, and Pt exhibit a significant shift after AVO and Pt get into contact, suggesting the strong ... h illumination, the photocatalytic H2 evolution amount from AVO/Pt is improved up to 1400 μmol, which ...

Tópico(s): Copper-based nanomaterials and applications

2021 - Elsevier BV | International Journal of Hydrogen Energy

Artigo Acesso aberto Brasil Produção Nacional Revisado por pares

Deusivânia Vieira da Silva Falcão, Nádia Maria Ribeiro Salomão,

O presente estudo enfoca a figura dos avós a fim de apresentar o papel que exercem, especificamente, diante da maternidade adolescente. Nesse prisma, apresentam-se conteúdos acerca dos aspectos psicossocial e ... a maioria das pesquisas enfatiza a figura das avós maternas dos bebês. Em suma, foi constatado que ... três situações típicas a serem observadas nos relacionamentos avós-mães adolescentes: os avós que assumem a responsabilidade pelo cuidado infantil; os avós que ficam envergonhados com a gravidez, têm pouca ...

Tópico(s): Family Dynamics and Relationships

2005 - PONTIFÍCIA UNIVERSIDADE CATÓLICA DE CAMPINAS | Estudos de Psicologia (Campinas)

Artigo Revisado por pares

R. Simm, R. E. White, Richard Uden,

AVO crossplots are a simple and elegant way of representing AVO data. Offset variations in amplitude for reflecting interfaces ... is an ideal way of examining differences in AVO responses that may be related to lithologic or ... R0) and gradient (G). The early literature approached AVO crossplots from the point of view of rock ... against the fluid line might provide an optimum AVO indicator. Figure 1. AVO classes and the AVO crossplot. The similarity of the fluid-line trend to trends on time-window AVO crossplots generated from seismic was compelling, and many ...

Tópico(s): Geochemistry and Geologic Mapping

2000 - Society of Exploration Geophysicists | The Leading Edge

Artigo Revisado por pares

Tor Arne Johansen, Leif Bruland, J. Lutro,

... the need for tracking the amplitude versus offset (AVO) occurs in several situations, for example in order ... zero‐offset amplitude, to reveal areas with particular AVO characteristics, or to compress the AVO so that it is more easily obtainable at ... amplitude or stack value. We outline how the AVO of seismic data may be extracted and classified ... to a general polynomial fit is that the AVO may be classified by a unique Spectrum of ... no effect of a limited spatial bandwidth. The AVO of normal‐moveout corrected data may be represented ...

Tópico(s): Seismology and Earthquake Studies

1995 - Wiley | Geophysical Prospecting

Artigo Revisado por pares

Christopher P. Ross, Daniel L. Kinman,

The use of amplitude variation with offset (AVO) attribute sections such as the product of the normal incidence trace (A) and the gradient trace (B) have been used extensively in bright spot AVO analysis and interpretation. However, while these sections have ... anomalies. Analyzing nonbright‐spot seismic data with common AVO attribute sections will: (1) not detect the gas‐ ... encasing shales, or (2) yield an incorrect (negative) AVO product if the normal incidence and gradient values are opposite in sign. We divide nonbright‐spot AVO offset responses into two subcategories: those with phase ...

Tópico(s): Seismic Waves and Analysis

1995 - Society of Exploration Geophysicists | Geophysics

Artigo Revisado por pares

Tad M. Smith, Carl Sondergeld,

... on bright‐spot and amplitude variation with offset (AVO) technology to help identify oil‐ and gas‐charged ... build robust models for the conditions under which AVO is useful as a fluid and/or lithology indicator. We build subregional AVO background trends for both brine‐ and gas‐saturated ... shale and sands (brine saturated). Simple models of AVO gradient and intercept are constructed as a function ... of these data in the context of linearized AVO models. In addition to the in‐situ brine ... also calculated. These trend models indicate that the AVO response is suppressed (although still positive) below a ...

Tópico(s): Hydrocarbon exploration and reservoir analysis

2001 - Society of Exploration Geophysicists | Geophysics