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1.
Behav Sci (Basel) ; 12(1)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35049628

RESUMO

Recent U.S. elections have witnessed the Democrats nominating both black and female presidential candidates, as well as a black and female vice president. The increasing diversity of the U.S. political elite heightens the importance of understanding the psychological factors influencing voter support for, or opposition to, candidates of different races and genders. In this study, we investigated the relative strength of the implicit biases for and against hypothetical presidential candidates that varied by gender and race, using an evaluative priming paradigm on a broadly representative sample of U.S. citizens (n = 1076). Our main research question is: Do measures of implicit racial and gender biases predict political attitudes and voting better than measures of explicit prejudice? We find that measures of implicit bias are less strongly associated with political attitudes and voting than are explicit measures of sexist attitudes and modern racism. Moreover, once demographic characteristics and explicit prejudice are controlled statistically, measures of implicit bias provide little incremental predictive validity. Overall, explicit prejudice has a far stronger association with political preferences than does implicit bias.

2.
Eur Heart J Cardiovasc Imaging ; 22(5): 505-515, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33245344

RESUMO

AIMS: To examine the characteristics/prognostic impact of diastolic dysfunction (DD) according to 2016 American Society of Echocardiography (ASE) and European Society of Cardiovascular Imaging (ESCVI) guidelines, and individual parameters of DD. METHODS AND RESULTS: Data were derived from a large multicentre mortality-linked echocardiographic registry comprising 436 360 adults with ≥1 diastolic function measurement linked to 100 597 deaths during 2.2 million person-years follow-up. ASE/European Association of Cardiovascular Imaging (EACVI) algorithms could be applied in 392 009 (89.8%) cases; comprising 11.4% of cases with 'reduced' left ventricular ejection fraction (LVEF < 50%) and 88.6% with 'preserved' LVEF (≥50%). Diastolic function was indeterminate in 21.5% and 62.2% of 'preserved' and 'reduced' LVEF cases, respectively. Among preserved LVEF cases, the risk of adjusted 5-year cardiovascular-related mortality was elevated in both DD [odds ratio (OR) 1.31, 95% confidence interval (CI) 1.22-1.42; P < 0.001] and indeterminate status cases (OR 1.11, 95% CI 1.04-1.18; P < 0.001) vs. no DD. Among impaired LVEF cases, the equivalent risk of cardiovascular-related mortality was 1.51 (95% CI 1.15-1.98, P < 0.001) for increased filling pressure vs. 1.25 (95% CI 0.96-1.64, P = 0.06) for indeterminate status. Mitral E velocity, septal e' velocity, E:e' ratio, and LAVi all correlated with mortality. On adjusted basis, pivot-points of increased risk for cardiovascular-related mortality occurred at 90 cm/s for E wave velocity, 9 cm/s for septal e' velocity, an E:e' ratio of 9, and an LAVi of 32 mL/m2. CONCLUSION: ASE/EACVI-classified DD is correlated with increased mortality. However, many cases remain 'indeterminate'. Importantly, when analysed individually, mitral E velocity, septal e' velocity, E:e' ratio, and LAVi revealed clear pivot-points of increased risk of cardiovascular-related mortality.


Assuntos
Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Adulto , Austrália/epidemiologia , Diástole , Feminino , Humanos , Masculino , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem
3.
Nat Methods ; 17(7): 741-748, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32483335

RESUMO

Two-photon microscopy is widely used to investigate brain function across multiple spatial scales. However, measurements of neural activity are compromised by brain movement in behaving animals. Brain motion-induced artifacts are typically corrected using post hoc processing of two-dimensional images, but this approach is slow and does not correct for axial movements. Moreover, the deleterious effects of brain movement on high-speed imaging of small regions of interest and photostimulation cannot be corrected post hoc. To address this problem, we combined random-access three-dimensional (3D) laser scanning using an acousto-optic lens and rapid closed-loop field programmable gate array processing to track 3D brain movement and correct motion artifacts in real time at up to 1 kHz. Our recordings from synapses, dendrites and large neuronal populations in behaving mice and zebrafish demonstrate real-time movement-corrected 3D two-photon imaging with submicrometer precision.


Assuntos
Imageamento Tridimensional/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Movimento , Peixe-Zebra
4.
Heart Lung Circ ; 29(6): e78-e83, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32467031

RESUMO

This Cardiac Society of Australia and New Zealand (CSANZ) Imaging Council Position Statement aims to guide local, regional and national clinical practice, and facilitate resource and echocardiographic service planning appropriately during the current COVID-19 global pandemic. General considerations include workforce arrangements and contingency plans, patient risk assessment for COVID-19 and level of care (personal protective equipment) for staff. Both outpatient and inpatient settings are addressed, including specific considerations in the in-patient setting including scanning protocols, screening modalities and indications for echocardiograms in the context of COVID-19 infection.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Atenção à Saúde/normas , Ecocardiografia/normas , Pandemias , Pneumonia Viral , Tomografia por Emissão de Pósitrons/normas , Austrália/epidemiologia , COVID-19 , Cardiologia , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/epidemiologia , Humanos , Nova Zelândia/epidemiologia , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/epidemiologia , Medição de Risco , SARS-CoV-2 , Sociedades Médicas
5.
Br J Sociol ; 71(4): 594-607, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32141060

RESUMO

The connection between social class and political preferences is among the most well established in the social sciences. This association is typically taken as prima facie evidence of economic self-interest: Classes hold different attitudes, values, and party preferences because they have different economic interests. However, this assumption has rarely been tested empirically. In this article, we use survey data from 18 West European countries to examine why classes differ on a central aspect of political preferences, namely their views on the desirability of income inequality. We find that only a moderate proportion of differences between employee classes in support for redistribution can be accounted for by contemporary differences in resources and risks; differences in economic interests to some degree account for the anti-redistributive preferences of the professional middle classes compared with the working class. However, the preferences of the self-employed have a different explanation; autonomy is a better explanation of the right-wing preferences of the self-employed compared with the working class.


Assuntos
Atitude , Renda , Classe Social , Emprego , Europa (Continente) , Feminino , Humanos , Masculino , Política , Fatores Socioeconômicos , Inquéritos e Questionários
6.
Water Res ; 173: 115549, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32086069

RESUMO

Wastewater treatment plants are a significant pathway of microplastics (MPs) to aquatic environments. To develop suitable management options and reduce microplastic emissions in treated effluent and sludge, we must first develop a reliable method to understand their transport and fate throughout the treatment process. An improved methodology was applied to determine the size, shape, polymer type and partitioning behaviour of MPs using a combination of oxidation treatment, fluorescent staining and Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) to detect small MPs ≤20 µm in wastewater. The mean number of MPs (<5 mm) detected using this methodology was 11.80 ± 1.10 MP/L in raw sewage, 5.23 ± 0.25 MP/L in degritted wastewater, 7.91 ± 0.44 MP/L in waste activated sludge and 2.76 ± 0.11 MP/L in the final treated effluent. An increase in MPs following primary screening suggests that WAS is a sink for several stealth microplastics, including glitter, which is returned to the effluent during the treatment process. The estimated MP removal efficiency for the studied WWTP is relatively poor compared with global data for secondary WWTPs, which is likely due to the release of partially treated effluent into the Pacific Ocean via a second discharge point. The information generated through this study can be useful to; firstly, inform on-site wastewater management practices, and secondly, reduce MP concentrations in final treated effluents discharged to the marine environment.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Monitoramento Ambiental , Microplásticos , Plásticos , Esgotos , Eliminação de Resíduos Líquidos
7.
Langmuir ; 35(10): 3615-3623, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30747538

RESUMO

Interfacial gas enrichment (IGE) of dissolved gases in water is shown to govern the strong attraction between solid hydrophobic surfaces of an atomic force microscopy (AFM) colloidal probe and solid substrate. However, the role of IGE in controlling the attraction between fluid-fluid interfaces of foam films and emulsion films is difficult to establish by AFM techniques because of the extremely fast coalescence. Here, we applied droplet-based microfluidics to capture the fast coalescence event under the creeping flow condition and quantify the effect of IGE on the drainage and stability of water films between coalescing oil droplets. The amount of dissolved gases is controlled by partially degassing the oil phase. When the amount of dissolved gases (oxygen) in oil decreases (from 7.89 to 4.59 mg/L), the average drainage time of coalescence significantly increases (from 19 to 50 ms). Our theoretical quantification of the coalescence by incorporating IGE into the multilayer van der Waals attraction theory confirms the acceleration of film drainage dynamics by the van der Waals attractive force generated by IGE. The thickness of the IGE layer decreases from 5.5 to 4.9 nm when the amount of dissolved gas decreases from 7.89 to 4.59 mg/L. All these results establish the universal role of dissolved gases in governing the strong attraction between particulate hydrophobic interfaces.

8.
Lab Chip ; 18(24): 3770-3779, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30426126

RESUMO

A liquid marble is a microliter-sized droplet coated with hydrophobic powder. The porous coating prevents the liquid content from being in direct physical contact with its surroundings, making the liquid marble perfectly non-wetting. On the one hand, the non-wetting ability allows the liquid marble to float and move across a liquid surface with little resistance. On the other hand, the porosity enables gas exchange between the liquid marble and its surroundings. These properties allow the liquid marble to serve as a bioreactor platform for important applications such as cell culture. Liquid marbles floating on a free liquid surface prevent evaporation due to the high humidity near the liquid surface. Moving a floating liquid marble allows for stirring and mixing inside the liquid marble. This paper reports a novel technique for manipulating a floating liquid marble using dielectrophoresis. A relatively simple setup can move liquid marbles of various sizes across the water surface at high speeds. We also present an analytical model to model and accurately predict the motion of the floating liquid marble. The technique reported here potentially allows for high-throughput and efficient handling of floating liquid marbles as a digital microfluidics platform.

9.
Soc Sci Res ; 76: 132-143, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30268275

RESUMO

Contrary to much conventional wisdom, this article shows that class is still used by people to sort others into groups, that this sorting is largely on the basis of income and occupation and that it occurs in conditions of both high and low income inequality. Uniquely, we use both open-ended survey questions and a factorial survey experiment to show that people from high (Britain) and low (Denmark) inequality countries are willing to define classes and they do so mainly in terms of job and income. Even though people in the two countries classify others using somewhat different class labels - with working class labels being used more frequently in Britain than in Denmark - we find a common underlying pattern to the classification. This indicates that class categorization takes place according to a strong underlying mental schema.

10.
Front Chem ; 6: 259, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013967

RESUMO

Dynamic surface wetting of particles in contact with droplet is a complex phenomenon ubiquitously encountered in many multiphase systems of industrial importance. In this study, we address this aspect by investigating impact behavior of a water droplet (diameter = 2.9 ± 0.1 mm) in the Weber number (We) range from ~4 to 104 on a stationary spherical brass particle (diameter = 10 mm) with and without heat transfer using a combination of high speed imaging and computational fluid dynamics (CFD) modeling approach. In cold state interactions (20°C), droplet exhibited oscillatory interfacial motion comprising periodic spreading and recoiling motion. Interactions involving heat transfer were studied in film boiling regime (350°C) and two outcomes were noted-droplet rebound and disintegration. A coupled Level Set and Volume of Fluid (VOF) approach based multiphase CFD model was utilized to predict the dynamic spread ratio and transient evolution of droplet shape during the interaction. To capture the complex contact line motion realistically, a continuous time varying profile of experimentally measured dynamic contact angles was used as a wall boundary condition for the cold interactions which provided good agreement with experimentally measured droplet spread ratio. In film boiling regime, droplet spread ratio was correlated to impact Weber number and a power law trend was obtained. Rebound and disintegration outcomes were characterized by the droplet-particle contact time. For simulating interactions in film boiling regime, a constant contact angle in the limit of super-hydrophobic surface was implemented in the CFD model to account for the apparent non-wetting effect due to vapor film formation at the contact area. A sensitivity analysis was performed involving three different contact angle boundary conditions (θ s = 150, 160, and 170°) to represent the surface hydrophobicity. CFD model predicted interaction outcomes and droplet spread ratios were in reasonable agreement with the experiment at different impact Weber numbers. Increase in spherical surface heat flux and corresponding rise in droplet temperature at different impact Weber numbers were also quantified which showed an increasing trend up to a critical Weber number for droplet disintegration.

11.
Sci Rep ; 6: 38346, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27910916

RESUMO

This paper investigates the friction coefficient of a moving liquid marble, a small liquid droplet coated with hydrophobic powder and floating on another liquid surface. A floating marble can easily move across water surface due to the low friction, allowing for the transport of aqueous solutions with minimal energy input. However, the motion of a floating marble has yet to be systematically characterised due to the lack of insight into key parameters such as the coefficient of friction between the floating marble and the carrier liquid. We measured the coefficient of friction of a small floating marble using a novel experimental setup that exploits the non-wetting properties of a liquid marble. A floating liquid marble pair containing a minute amount magnetite particles were immobilised and then released in a controlled manner using permanent magnets. The capillarity-driven motion was analysed to determine the coefficient of friction of the liquid marbles. The "capillary charge" model was used to fit the experimental results. We varied the marble content and carrier liquid to establish a relationship between the friction correction factor and the meniscus angle.

12.
Nat Methods ; 13(12): 1001-1004, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27749836

RESUMO

Understanding how neural circuits process information requires rapid measurements of activity from identified neurons distributed in 3D space. Here we describe an acousto-optic lens two-photon microscope that performs high-speed focusing and line scanning within a volume spanning hundreds of micrometers. We demonstrate its random-access functionality by selectively imaging cerebellar interneurons sparsely distributed in 3D space and by simultaneously recording from the soma, proximal and distal dendrites of neocortical pyramidal cells in awake behaving mice.


Assuntos
Comportamento Animal/fisiologia , Imageamento Tridimensional/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Atividade Motora/fisiologia , Neurônios/fisiologia , Imagens com Corantes Sensíveis à Voltagem/métodos , Potenciais de Ação/fisiologia , Animais , Córtex Cerebelar/citologia , Córtex Cerebelar/fisiologia , Dendritos/fisiologia , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Interneurônios/fisiologia , Camundongos , Camundongos Transgênicos , Técnicas de Patch-Clamp , Células Piramidais/fisiologia , Córtex Visual/citologia , Córtex Visual/fisiologia
13.
Langmuir ; 32(44): 11520-11524, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27753495

RESUMO

This paper reports the direct and precise measurement of bubble coalescence in salt solutions using microfluidics. We directly visualized the bubble coalescence process in a microchannel using high-speed imaging and evaluated the shortest coalescence time to determine the transition concentration of sodium halide solutions. We found the transition concentration is ion-specific, and the capacity of sodium halide salts to inhibit bubble coalescence follows the order of NaF > NaCl > NaBr > NaI. The microfluidic method overcomes the inherent uncertainties in conventional large-scale devices and methods.

14.
Opt Express ; 24(6): 6283-99, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27136821

RESUMO

Acousto-optic deflectors (AODs) arranged in series and driven with linearly chirped frequencies can rapidly focus and tilt optical wavefronts, enabling high-speed 3D random access microscopy. Non-linearly chirped acoustic drive frequencies can also be used to shape the optical wavefront allowing a range of higher-order aberrations to be generated. However, to date, wavefront shaping with AODs has been achieved by using single laser pulses for strobed illumination to 'freeze' the moving acoustic wavefront, limiting voxel acquisition rates. Here we show that dynamic wavefront shaping can be achieved by applying non-linear drive frequencies to a pair of AODs with counter-propagating acoustic waves, which comprise a cylindrical acousto-optic lens (AOL). Using a cylindrical AOL we demonstrate high-speed continuous axial line scanning and the first experimental AOL-based correction of a cylindrical lens aberration at 30 kHz, accurate to 1/35th of a wave at 800 nm. Furthermore, we develop a model to show how spherical aberration, which is the major aberration in AOL-based remote-focusing systems, can be partially or fully corrected with AOLs consisting of four or six AODs, respectively.

15.
Langmuir ; 32(24): 6097-104, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27230102

RESUMO

Liquid marble is a liquid droplet coated with particles. Recently, the evaporation process of a sessile liquid marble using geometric measurements has attracted great attention from the research community. However, the lack of gravimetric measurement limits further insights into the physical changes of a liquid marble during the evaporation process. Moreover, the evaporation process of a marble containing a liquid binary mixture has not been reported before. The present paper investigates the effective density and the effective surface tension of an evaporating liquid marble that contains aqueous ethanol at relatively low concentrations. The effective density of an evaporating liquid marble is determined from the concurrent measurement of instantaneous mass and volume. Density measurements combined with surface profile fitting provide the effective surface tension of the marble. We found that the density and surface tension of an evaporating marble are significantly affected by the particle coating.

16.
Soc Sci Res ; 57: 31-48, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26973030

RESUMO

Despite continuing for over two decades, the debate about the nature of the trends in religiosity in post-Communist Eastern Europe remains unresolved: some arguing that these countries are undergoing the same process of secularization as the West, while others insist that the entire region is experiencing a religious revival. Using national sample surveys from the early 1990s to 2007 to examine the change in demographic predictors of religiosity, we show that Catholic and Orthodox countries are experiencing different trends, the first group displaying evidence of secularization and the second of revival, and that these two different trends are likely to derive from the legacies of state repression and the differing abilities of the churches to resist such repression. We argue that the current literature has thus taken a mistakenly general approach, and that the post-Communist region consists of at least two distinct groups of societies with different trends in religiosity.


Assuntos
Sistemas Políticos , Religião , Secularismo , Mudança Social , Catolicismo , Comunismo , Demografia , Europa Oriental , Humanos , Inquéritos e Questionários
17.
Animals (Basel) ; 5(2): 361-94, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-26479240

RESUMO

The objective of this review is to point out that the global dialog on reducing greenhouse gas emissions in animal agriculture has, thus far, not adequately considered animal welfare in proposed climate change mitigation strategies. Many suggested approaches for reducing emissions, most of which could generally be described as calls for the intensification of production, can have substantial effects on the animals. Given the growing world-wide awareness and concern for animal welfare, many of these approaches are not socially sustainable. This review identifies the main emission abatement strategies in the climate change literature that would negatively affect animal welfare and details the associated problems. Alternative strategies are also identified as possible solutions for animal welfare and climate change, and it is suggested that more attention be focused on these types of options when allocating resources, researching mitigation strategies, and making policy decisions on reducing emissions from animal agriculture.

19.
Opt Express ; 23(18): 23493-510, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26368449

RESUMO

A spherical acousto-optic lens (AOL) consists of four acousto-optic deflectors (AODs) that can rapidly and precisely control the focal position of an optical beam in 3D space. Development and application of AOLs has increased the speed at which 3D random access point measurements can be performed with a two-photon microscope. This has been particularly useful for measuring brain activity with fluorescent reporter dyes because neuronal signalling is rapid and sparsely distributed in 3D space. However, a theoretical description of light propagation through AOLs has lagged behind their development, resulting in only a handful of simplified principles to guide AOL design and optimization. To address this we have developed a ray-based computer model of an AOL incorporating acousto-optic diffraction and refraction by anisotropic media. We extended an existing model of a single AOD with constant drive frequency to model a spherical AOL: four AODs in series driven with linear chirps. AOL model predictions of the relationship between optical transmission efficiency and acoustic drive frequency including second order diffraction effects closely matched experimental measurements from a 3D two-photon AOL microscope. Moreover, exploration of different AOL drive configurations identified a new simple rule for maximizing the field of view of our compact AOL design. By providing a theoretical basis for understanding optical transmission through spherical AOLs, our open source model is likely to be useful for comparing and improving different AOL designs, as well as identifying the acoustic drive configurations that provide the best transmission performance over the 3D focal region.


Assuntos
Acústica/instrumentação , Desenho Assistido por Computador , Lentes , Luz , Modelos Teóricos , Espalhamento de Radiação , Simulação por Computador , Sistemas Microeletromecânicos/instrumentação
20.
Phys Chem Chem Phys ; 16(45): 24661-5, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25242240

RESUMO

The Jones-Ray effect is shown to be governed by a different mechanism to enhanced anion adsorption. Halide ions at sub-molar concentrations are not exposed to the vapour phase; instead their first-solvating shell intimately interacts with the outmost water layer. Our novel proposal opens challenges for predicting related interfacial phenomena consistently.


Assuntos
Halogênios/química , Água/química , Modelos Moleculares , Conformação Molecular , Volatilização
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