1,287 research outputs found
Molecular interactions between the specialist herbivore Manduca sexta (Lepidoptera, Sphigidae) and its natural host Nicotiana attenuata. VIII. An unbiased GCxGC-ToFMS analysis of the plant´s elicited volatile emissions
Treating wounds in Nicotiana attenuata leaves with Manduca sexta oral secretions (W+OS) mimics most changes elicited by M. sexta herbivory, but an unbiased analysis of the effect of the different OS constituents on volatile emissions is lacking. We used two-dimensional gas chromatography/time-of-flight (GCxGC-ToF) mass spectrometry combined with multivariate statistics to parse volatiles into regulatory patterns. Volatiles released by wounding alone and by the alkalinity of OS were assessed by applying a buffer known to mimic the pH-mediated changes of OS elicitation (pectin methyl esterase activation and methanol release). The activities of fatty acid amino acid conjugates, well-known elicitors of antiherbivore defenses, and of 2-hydroxyoctadecatrienoic acid, a newly discovered signal in OS, were determined. Approximately 400 analytes were detected after deconvolution and alignment of GCxGC data; 35 volatiles were significantly regulated upon W+OS. Two-thirds of these were specifically regulated by OS, being either amplified (most terpenoids and certain hexenylesters) or strongly repressed (many short-chain alcohols and some aromatic and hexenylester derivatives). Fatty acid amino acid conjugates played a central role in this pattern of regulation, since they induced the emission of half of OS-elicited volatiles and inhibited the production of almost all OS-repressed volatiles; 2-hydroxyoctadecatrienoic acid influenced emission of trans-α-bergamotene, while other unknown OS constituents amplified hexenylester production. We conclude that the complex bouquet of herbivory-elicited volatiles results from the complex modulations of the wound response by diverse cues found in OS. This work also underscores the value of ultra-high-resolution GCxGC-ToF analysis combined with the nontargeted mining of the resulting data
Smart Institutions for Smart Cities
Smart cities employ creativity of the population for innovations supporting social and economic development. In this context, this paper explores the role of framework conditions on special supply effects of university hospitals, which can invite further research institutions for intense collaboration, thereby stimulating innovations. The case study, comparing a hospital in Russia with one in Germany, is based on the concept of the employment multiplier. The results show that exogenously given, but, more importantly, also modifiable framework conditions lead to large differences regarding the employment multiplier. Thus, it should be the concern of smart cities to make smart use of their institutions, such as university hospitals, by adjusting the conditions, under which they are operating. © 2018 Institute of Physics Publishing. All rights reserved
On The Phase Structure and Thermodynamic Geometry of R-Charged Black Holes
We study the phase structure and equilibrium state space geometry of
R-charged black holes in , 4 and 7 and the corresponding rotating ,
and branes. For various charge configurations of the compact black
holes in the canonical ensemble we demonstrate new liquid-gas like phase
coexistence behaviour culminating in second order critical points. The critical
exponents turn out to be the same as that of four dimensional asymptotically
AdS black holes in Einstein Maxwell theory. We further establish that the
regions of stability for R-charged black holes are, in some cases, more
constrained than is currently believed, due to properties of some of the
response coefficients. The equilibrium state space scalar curvature is
calculated for various charge configurations, both for the case of compact as
well as flat horizons and its asymptotic behaviour with temperature is
established.Comment: 1 + 33 pages, LaTeX, 25 figures. References adde
La dame aux camélias
Alexander Dumas (fils)'nin Hazine-i Fünun'da yayımlanan La Dame aux Camélias adlı romanının ilk ve son tefrikalarıTefrikanın devamına rastlanmamış, tefrika yarım kalmıştır
Net carbon emissions from deforestation in Bolivia during 1990-2000 and 2000-2010: results from a carbon bookkeeping model
Accurate estimates of global carbon emissions are critical for understanding global warming. This paper estimates net carbon emissions from land use change in Bolivia during the periods 1990-2000 and 2000-2010 using a model that takes into account deforestation, forest degradation, forest regrowth, gradual carbon decomposition and accumulation, as well as heterogeneity in both above ground and below ground carbon contents at the 10 by 10 km grid level. The approach permits detailed maps of net emissions by region and type of land cover. We estimate that net CO2 emissions from land use change in Bolivia increased from about 65 million tons per year during 1990-2000 to about 93 million tons per year during 2000-2010, while CO2 emissions per capita and per unit of GDP have remained fairly stable over the sample period. If we allow for estimated biomass to increase in mature forests, net CO2 emissions drop to close to zero. Finally, we find these results are robust to alternative methods of calculating emissions
Lack of hydroxylation-induced migration with 4-iodophenylalanine
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32730/1/0000098.pd
Diurnal variations of ambient particulate wood burning emissions and their contribution to the concentration of Polycyclic Aromatic Hydrocarbons (PAHs) in Seiffen, Germany
Residential wood burning is becoming an increasingly important cause of air quality problems since it has become a popular source of alternative energy to fossil fuel. In order to characterize the contribution of residential wood burning to local particle pollution, a field campaign was organized at the village of Seiffen (Saxony, Germany). During this campaign, an Aerosol Mass Spectrometer (AMS) was deployed in parallel to a PM<sub>1</sub> high volume filter sampler. The AMS mass spectra were analyzed using Positive Matrix Factorization (PMF) to obtain detailed information about the organic aerosol (OA). Biomass-burning organic aerosol (BBOA), Hydrocarbon-like organic aerosol (HOA), and Oxygenated Organic Aerosol (OOA) were identified and represented 20%, 17% and 62% of total OA, respectively. Additionally, Polycyclic Aromatic Hydrocarbons (PAH) were measured by the AMS with an average concentration of 10 ng m<sup>−3</sup> and short term events of extremely high PAH concentration (up to 500 ng m<sup>−3</sup>) compared to the mean PAH value were observed during the whole measurement period. A comparison with the results from PM<sub>1</sub> filter samples showed that the BBOA factor and the AMS PAH are good indicators of the total concentration of the different monosaccharide anhydrides and PAH measured on the filter samples. Based on its low correlation with CO and the low car traffic, the HOA factor was considered to be related to residential heating using liquid fuel. An influence of the time of the week (week vs. weekend) on the diurnal profiles of the different OA components was observed. The weekdays were characterized by two maxima; a first one early in the morning and a stronger one in the evening. During the weekend days, the different OA components principally reached only one maximum in the afternoon. Finally, the PAH emitted directly from residential wood combustion was estimated to represent 1.5% of the total mass of the BBOA factor and around 62% of the total PAH concentration measured at Seiffen. This result highlights the important contribution of residential wood combustion to air quality and PAH emissions at the sampling place, which might have a significant impact on human health. Moreover, it also emphasizes the need for a better time resolution of the chemical characterization of toxic particulate compounds in order to provide more information on variations of the different sources through the days as well as to better estimate the real human exposure
Black Hole Thermodynamics in Horava Lifshitz Gravity and the Related Geometry
Recently, Hoava proposed a non-relativistic renormalizable theory
of gravity which is essentially a field theoretic model for a UV complete
theory of gravity and reduces to Einstein gravity with a non-vanishing
cosmological constant in IR. Also the theory admits a Lifshitz scale-invariance
in time and space with broken Lorentz symmetry at short scale. On the other
hand, at large distances higher derivative terms do not contribute and the
theory coincides with general relativity. Subsequently, Cai and his
collaborators and then Catiuo et al have obtained black hole solutions in this
gravity theory and studied the thermodynamic properties of the black hole
solution. In the present paper, we have investigated the black hole
thermodynamic for two choices of the entropy function - a classical and a
topological in nature. Finally, it is examined whether a phase transition is
possible or not.Comment: 8 figure
Thermodynamical Metrics and Black Hole Phase Transitions
An important phase transition in black hole thermodynamics is associated with
the divergence of the specific heat with fixed charge and angular momenta, yet
one can demonstrate that neither Ruppeiner's entropy metric nor Weinhold's
energy metric reveals this phase transition. In this paper, we introduce a new
thermodynamical metric based on the Hessian matrix of several free energy. We
demonstrate, by studying various charged and rotating black holes, that the
divergence of the specific heat corresponds to the curvature singularity of
this new metric. We further investigate metrics on all thermodynamical
potentials generated by Legendre transformations and study correspondences
between curvature singularities and phase transition signals. We show in
general that for a system with n-pairs of intensive/extensive variables, all
thermodynamical potential metrics can be embedded into a flat (n,n)-dimensional
space. We also generalize the Ruppeiner metrics and they are all conformal to
the metrics constructed from the relevant thermodynamical potentials.Comment: Latex, 25 pages, reference added, typos corrected, English polished
and the Hawking-Page phase transition clarified; to appear in JHE
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