299 research outputs found
Resting respiratory tract dendritic cells preferentially stimulate T helper cell Type 2(Th2) responses and require obligatory cytokine signals for induction of Th1 immunity
Consistent with their role in host defense, mature dendritic cells (DCs) from central lymphoid organs preferentially prime for T helper cell type 1 (Th1)-polarized immunity. However, the âdefaultâ T helper response at mucosal surfaces demonstrates Th2 polarity, which is reflected in the cytokine profiles of activated T cells from mucosal lymph nodes. This study on rat respiratory tract DCs (RTDCs) provides an explanation for this paradox. We demonstrate that freshly isolated RTDCs are functionally immature as defined in vitro, being surface major histocompatibility complex (MHC) II lo, endocytosishi, and mixed lymphocyte reactionlo, and these cells produce mRNA encoding interleukin (IL)-10. After ovalbumin (OVA)-pulsing and adoptive transfer, freshly isolated RTDCs preferentially stimulated Th2-dependent OVA-specific immunoglobulin (Ig)G1 responses, and antigen-stimulated splenocytes from recipient animals produced IL-4 in vitro. However, preculture with granulocyte/macrophage colony stimulating factor increased their in vivo IgG priming capacity by 2â3 logs, inducing production of both Th1- and Th2-dependent IgG subclasses and high levels of IFN-Îł by antigen-stimulated splenocytes. Associated phenotypic changes included upregulation of surface MHC II and B7 expression and IL-12 p35 mRNA, and downregulation of endocytosis, MHC II processingâ associated genes, and IL-10 mRNA expression. Full expression of IL-12 p40 required additional signals, such as tumor necrosis factor α or CD40 ligand. These results suggest that the observed Th2 polarity of the resting mucosal immune system may be an inherent property of the resident DC population, and furthermore that mobilization of Th1 immunity relies absolutely on the provision of appropriate microenvironmental costimuli
Absolute wave-number measurements in 130Te2: Reference lines spanning the 420.9-464.6-nm region
We have measured the absolute wave numbers of 39 transitions of 130Te2 spanning the spectral region of 420.9-464.6 nm to an accuracy of better than 2 parts in 109 by use of saturation spectroscopy and Fabry-PĂ©rot interferometry. These measurements provide a set of convenient and accurate transfer standards for laser wavelength calibration spanning the entire Stilbene-420 dye-tuning curve
An Alternative Method to Deduce Bubble Dynamics in Single Bubble Sonoluminescence Experiments
In this paper we present an experimental approach that allows to deduce the
important dynamical parameters of single sonoluminescing bubbles (pressure
amplitude, ambient radius, radius-time curve) The technique is based on a few
previously confirmed theoretical assumptions and requires the knowledge of
quantities such as the amplitude of the electric excitation and the phase of
the flashes in the acoustic period. These quantities are easily measurable by a
digital oscilloscope, avoiding the cost of expensive lasers, or ultrafast
cameras of previous methods. We show the technique on a particular example and
compare the results with conventional Mie scattering. We find that within the
experimental uncertainties these two techniques provide similar results.Comment: 8 pages, 5 figures, submitted to Phys. Rev.
Examining the Psychosocial and Behavioral Factors Associated with Adolescent Engagement in Multiple Types of Cyberdeviance: Results from an Australian Study
OnlinePublResearch has shown that psychosocial and behavioral factors are associated with engagement in a range of deviant behaviors across offline settings. To date, however, very little research has explored the impact of these factors in online contexts. This article addresses this gap by examining the psychosocial and behavioral factors associated with common types of adolescent cyberdeviance. This is accomplished through an empirical study of 327 adolescents enrolled in a high school located in a large Australian city. The study assesses various aspects of psychosocial and behavioral functioning using the Strengths and Difficulties Questionnaire (total difficulties, internalizing problems, externalizing problems, prosocial behavior), as well as numerous types of cyberdeviance relevant to young people, including cyberfraud, cyberhate, cyberviolence, sexting, digital piracy, hacking, and cyberbullying. A series of multivariate logistic regression analyses were conducted to demonstrate the association between psychosocial and behavioral difficulties and various types of cyberdeviance, independent of gender, school grade, socioeconomic status, and engagement in offline delinquency. Results indicate that total difficulties, internalizing problems, and externalizing problems were significantly associated with greater likelihood of engagement in most types of cyberdeviance examined in this study, whereas prosocial behavior was associated with a lower likelihood of engagement in digital piracy only. A discussion of the findings highlights the importance of understanding these factors in a digital context, as well as demonstrating the need to account for them when designing targeted interventions.Russell Brewer, Tyson Whitten, Katie Logos, Morgan Sayer, Colette Langos, Thomas J. Holt, Jesse Cale, Andrew Goldsmit
Cost and performance of some carbon capture technology options for producing different quality COâ product streams
A techno-economic assessment of power plants with CO2 capture technologies with a focus on process scenarios that deliver different grades of CO2 product purity is presented. The three leading CO2 capture technologies are considered, namely; oxyfuel combustion, pre-combustion and post-combustion capture. The study uses a combination of process simulation of flue gas cleaning processes, modelling with a power plant cost and performance calculator and literature values of key performance criteria in order to evaluate the performance, cost and CO2 product purity of the considered CO2 capture options. For oxyfuel combustion capture plants, three raw CO2 flue gas processing strategies of compression and dehydration only, double flash system purification and distillation purification are considered. Analysis of pre-combustion capture options is based on integrated gasification combined cycle plants using physical solvent systems for capturing CO2 and sulfur species via three routes; co-capture of sulfur impurities with the CO2 stream using Selexolâą solvent, separate capture of CO2 and sulfur impurities using Selexolâą, and RectisolÂź solvent systems for separate capture of sulfur impurities and CO2. Analysis of post-combustion capture plants was made with and without some conventional pollution control devices. The results highlight the wide variation in CO2 product purity for different oxyfuel combustion capture scenarios and the wide cost variation for the pre-combustion capture scenarios. The post-combustion capture plant with conventional pollution control devices offers high CO2 purity (99.99 mol%) for average cost of considered technologies. The calculations performed will be of use in further analyses of whole chain CCS for the safe and economic capture, transport and storage of CO2
Just married: the synergy between feminist criminology and the Tripartite Cybercrime Framework
This article is a theoretical treatment of feminist epistemology of crime, which advocates the centrality of gender as a theoretical starting point for the investigating of digital crimes. It does so by exploring the synergy between the feminist perspectives and the Tripartite Cybercrime Framework (TCF) (which argues that three possible factors motivate cybercrimes â socioeconomic, psychosocial, and geopolitical) to critique mainstream criminology and the meaning of the term âcybercrimeâ. Additionally, the article examines gender gaps in online harassment, cyberâbullying, cyberâfraud, revenge porn, and cyberâstalking to demonstrate that who is victimised, why, and to what effect are the critical starting points for the analysis of the connections between gender and crimes. In turn, it uses the lens of intersectionality to acknowledge that, while conceptions of gender and crime interact, they intersect with other categories (e.g., sexuality) to provide additional layers of explanation. To nuance the utilitarian value of the synergy between the TCF and the feminist perspectives, the focus shifts to a recent case study (which compared socioeconomic and psychosocial cybercrimes). The article concludes that, while online and offline lives are inextricably intertwined, the victimisations in psychosocial cybercrimes may be more gendered than in socioeconomic cybercrimes. These contributions align the TCF to the feminist epistemology of crime in their attempt to move gender analysis of digital crimes âfrom margin to centreâ
Meta-analysis identifies seven susceptibility loci involved in the atopic March
Eczema often precedes the development of asthma in a disease course called the a 'atopic march'. To unravel the genes underlying this characteristic pattern of allergic disease, we conduct a multi-stage genome-wide association study on infantile eczema followed by childhood asthma in 12 populations including 2,428 cases and 17,034 controls. Here we report two novel loci specific for the combined eczema plus asthma phenotype, which are associated with allergic disease for the first time; rs9357733 located in EFHC1 on chromosome 6p12.3 (OR 1.27; P=2.1 Ă 10 a'8) and rs993226 between TMTC2 and SLC6A15 on chromosome 12q21.3 (OR 1.58; P=5.3 Ă 10 a'9). Additional susceptibility loci identified
On ecological conceptualizations of perceptual systems and action systems
This article examines Gibson's concept of perceptual system and Reed's concept of action system. After discussing several assumptions underlying these concepts, the ontological status of these systems is considered. It is argued that perceptual systems and action systems should be conceptualized neither as parts of an animal's body nor as softly (temporarily) assembled devices; rather, they are best understood as animals' abilities to achieve functional relationships, that is, as dispositional properties. This conceptualization entails that these systems are relatively permanent properties of the animal that are causally supported by, though not identical to, anatomical substrates. Further, it entails that it is the animal that perceives and acts, not its perceptual and action systems
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