128 research outputs found
Geometric Metastability, Quivers and Holography
We use large N duality to study brane/anti-brane configurations on a class of
Calabi-Yau manifolds. With only branes present, the Calabi-Yau manifolds in
question give rise to N=2 ADE quiver theories deformed by superpotential terms.
We show that the large N duality conjecture of hep-th/0610249 reproduces
correctly the known qualitative features of the brane/anti-brane physics. In
the supersymmetric case, the gauge theories have Seiberg dualities which are
represented as flops in the geometry. Moreover, the holographic dual geometry
encodes the whole RG flow of the gauge theory. In the non-supersymmetric case,
the large N duality predicts that the brane/anti-brane theories also enjoy such
dualities, and allows one to pick out the good description at a given energy
scale.Comment: v2: 56 pages, 4 figures, harvmac, abstract correcte
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A systemic review and meta-analysis on the antihypertensive effect of aromatherapy essential oils
Purpose: This study is a systemic review of experimental results on the effects of aromatherapy on blood pressure.
Materials and Methods: Journal articles published to December, 2017, were retrieved from twelve databases. Randomized controlled trials in which were evaluated for changes in blood pressure following aromatherapy were selected. Risks of bias were assessed using the risk-of-bias (ROB) tool of the Cochrane Collaboration. Meta-analysis were dine using RevMan.
Results: Of the 2545 articles retrieved from the electronic databases, 580 duplicate articles and 1891 articles that were unrelated to the PICO (patient/problem, intervention, comparison, outcome) elements or did not satisfy the inclusion criteria excluded. Of the remaining 74 articles, 15 found to satisfy the inclusion criteria after full-text review and therefore selected for analysis. The findings of meta-analysis of 11 of these 15 articles revealed that essential oil inhalation and massage effectively decreased both systolic (n = 379; mean difference [MD], -4.72; 95% confidence interval [CI], -8.38 to -1.07) and diastolic (n = 379; MD, -2.42; 95% CI, -4.46 to -0.38) pressure.
Conclusions: Essential oil inhalation and massage therapy can effectively decrease systolic and diastolic pressure in health adults as well as in patients with hypertension
Identification of caspase 3 motifs and critical aspartate residues in human Phospholipase D1b and Phopsholipase D2a
Stimulation of mammalian cells frequently initiates phospholipase D-catalysed
hydrolysis of phosphatidylcholine in the plasma membrane to yield phosphatidic acid
(PA) a novel lipid messenger. PA plays a regulatory role in important cellular
processes such as secretion, cellular shape change and movement. A number of
studies have highlighted that PLD-based signalling also plays a pro-mitogenic and
pro-survival role in cells and therefore anti-apoptotic. We show that human PLD1b
and PLD2a contain functional caspase-3 cleavage sites and identify the critical
aspartate residues within PLD1b that affect its activation by phorbol esters and
attenuate phosphatidylcholine hydrolysis during apoptosis
A Pectate Lyase-Coding Gene Abundantly Expressed during Early Stages of Infection Is Required for Full Virulence in Alternaria brassicicola
We thank Fred Brooks for insightful discussions on the roles of PL1332 on pathogenesis mechanisms employed by A. brassicicola.Alternaria brassicicola causes black spot disease of Brassica species. The functional importance of pectin digestion enzymes and unidentified phytotoxins in fungal pathogenesis has been suspected but not verified in A. brassicicola. The fungal transcription factor AbPf2 is essential for pathogenicity and induces 106 genes during early pathogenesis, including the pectate lyase-coding gene, PL1332. The aim of this study was to test the importance and roles of PL1332 in pathogenesis. We generated deletion strains of the PL1332 gene, produced heterologous PL1332 proteins, and evaluated their association with virulence. Deletion strains of the PL1332 gene were approximately 30% less virulent than wild-type A. brassicicola, without showing differences in colony expansion on solid media and mycelial growth in nutrient-rich liquid media or minimal media with pectins as a major carbon source. Heterologous PL1332 expressed as fusion proteins digested polygalacturons in vitro. When the fusion proteins were injected into the apoplast between leaf veins of host plants the tissues turned dark brown and soft, resembling necrotic leaf tissue. The PL1332 gene was the first example identified as a general toxin-coding gene and virulence factor among the 106 genes regulated by the transcription factor, AbPf2. It was also the first gene to have its functions investigated among the 19 pectate lyase genes and several hundred putative cell-wall degrading enzymes in A. brassicicola. These results further support the importance of the AbPf2 gene as a key pathogenesis regulator and possible target for agrochemical development.Yeshttp://www.plosone.org/static/editorial#pee
Layered composite membranes based on porous PVDF coated with a thin, dense PBI layer for vanadium redox flow batteries
A commercial porous polyvinylidene fluoride membrane (pore size 0.65 μm, nominally 125 μm thick) is spray coated with 1.2–4 μm thick layers of polybenzimidazole. The area resistance of the porous support is 36.4 mΩ cm2 in 2 M sulfuric acid, in comparison to 540 mΩ cm2 for a 27 μm thick acid doped polybenzimidazole membrane, and 124 mΩ cm2 for PVDF-P20 (4 μm thick blocking layer). Addition of vanadium ions to the supporting electrolyte increases the resistance, but less than for Nafion. The expected reason is a change in the osmotic pressure when the ionic strength of the electrolyte is increased, reducing the water contents in the membrane. The orientation of the composite membranes has a strong impact. Lower permeability values are found when the blocking layer is oriented towards the vanadium-lean side in ex-situ measurements. Cells with the blocking layer on the positive side have significantly lower capacity fade, also much lower than cells using Nafion 212. The coulombic efficiency of cells with PVDF-PBI membranes (98.4%) is higher than that of cells using Nafion 212 (93.6%), whereas the voltage efficiency is just slightly lower, resulting in energy efficiencies of 85.1 and 83.3%, respectively, at 80 mA/cm2
A global experiment on motivating social distancing during the COVID-19 pandemic
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
New Era of Air Quality Monitoring from Space: Geostationary Environment Monitoring Spectrometer (GEMS)
GEMS will monitor air quality over Asia at unprecedented spatial and temporal resolution from GEO for the first time, providing column measurements of aerosol, ozone and their precursors (nitrogen dioxide, sulfur dioxide and formaldehyde).
Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in late 2019 - early 2020 to monitor Air Quality (AQ) at an unprecedented spatial and temporal resolution from a Geostationary Earth Orbit (GEO) for the first time. With the development of UV-visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO and aerosols) can be obtained. To date, all the UV-visible satellite missions monitoring air quality have been in Low Earth orbit (LEO), allowing one to two observations per day. With UV-visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be onboard the GEO-KOMPSAT-2 satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager (GOCI)-2. These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA's TEMPO and ESA's Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS)
Technical Change and Industrial Dynamics as Evolutionary Processes
Technical Change and Industrial Dynamics as Evolutionary Processes
A global experiment on motivating social distancing during the COVID-19 pandemic
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e. a controlling message) compared to no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly-internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared to the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly-internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing: Controlled motivation was associated with more defiance and less long-term behavioral intentions to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
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