4,094 research outputs found
Modelling the NO emissions from wildfires at the source level
There is a growing interest to characterize fire plumes in order to control
air quality during wildfire episodes and to estimate the carbon and ozone
balance of fire emissions. A numerical approach has been used to study the
mechanisms of NO formation at the source level in wildfires given that NO
plays an important role in the formation of ground-level ozone. The major
reaction mechanisms involved in NO chemistry have been identified using
reaction path analysis. Accordingly, a two-step global kinetic scheme in the
gas phase has been proposed herein to account for the volatile fuel-bound
nitrogen (fuel-N) conversion to NO, considering that the volatile fraction of
fuel-N is released as NH<sub>3</sub>. Data from simulations using the perfectly stirred
reactor (PSR) code from
CHEMKIN-II package with a detailed kinetic mechanism
(GDF-Kin<sup>®</sup> 3.0) have been used to calibrate
and evaluate the global model under typical wildfire conditions in terms of
the composition of the degradation gases of vegetation, the equivalence
ratio, the range of temperatures and the residence time
Caspase-1-driven neutrophil pyroptosis and its role in host susceptibility to Pseudomonas aeruginosa
Multiple regulated neutrophil cell death programs contribute to host defense against infections. However, despite expressing all necessary inflammasome components, neutrophils are thought to be generally defective in Caspase-1-dependent pyroptosis. By screening different bacterial species, we found that several Pseudomonas aeruginosa (P. aeruginosa) strains trigger Caspase-1-dependent pyroptosis in human and murine neutrophils. Notably, deletion of Exotoxins U or S in P. aeruginosa enhanced neutrophil death to Caspase-1-dependent pyroptosis, suggesting that these exotoxins interfere with this pathway. Mechanistically, P. aeruginosa Flagellin activates the NLRC4 inflammasome, which supports Caspase-1-driven interleukin (IL)-1β secretion and Gasdermin D (GSDMD)-dependent neutrophil pyroptosis. Furthermore, P. aeruginosa-induced GSDMD activation triggers Calcium-dependent and Peptidyl Arginine Deaminase-4-driven histone citrullination and translocation of neutrophil DNA into the cell cytosol without inducing extracellular Neutrophil Extracellular Traps. Finally, we show that neutrophil Caspase-1 contributes to IL-1β production and susceptibility to pyroptosis-inducing P. aeruginosa strains in vivo. Overall, we demonstrate that neutrophils are not universally resistant for Caspase-1-dependent pyroptosis
Analysis of Direct and Flanking Sound Transmission Between Rooms with Curtain Wall Facades
Curtain walls have nowadays reached good performance in terms of façade sound insulation, thermal insulation and solar protection.
In this work, flanking and direct structural transmission are analysed with reference to the joints of the mullion of the curtain wall with lightweight plasterboard partitions. Airborne sound insulation and vibrational measurements were made in two adjacent rooms affected by the acoustic problems determined by the curtain wall joint.
Traditional acoustic measurements carried out according to EN ISO 16283-1 highlight problems in sound insulation between rooms, but without any indication on different sound transmission paths through the wall. Vibrational measurements were made for every part of the system (frame columns and beams, windowsâ glasses, plasterboard wall, plasterboard false ceiling, etc.) to better understand the sound transmission paths in these kinds of structures.
Taking into account previous works and measurements made in this research field, different solutions for curtain wall structures are analysed and technical suggestions are given to improve airborne sound insulation between rooms separated by partitions mounted up to metal frames
Evaluating homophily in networks via HONTO (HOmophily Network TOol): a case study of chromosomal interactions in human PPI networks
It has been observed in different kinds of networks, such as social or biological ones, a typical behavior inspired by the general principle 'similarity breeds connections'. These networks are defined as homophilic as nodes belonging to the same class preferentially interact with each other. In this work, we present HONTO (HOmophily Network TOol), a user-friendly open-source Python3 package designed to evaluate and analyze homophily in complex networks. The tool takes in input from the network along with a partition of its nodes into classes and yields a matrix whose entries are the homophily/heterophily z-score values. To complement the analysis, the tool also provides z-score values of nodes that do not interact with any other node of the same class. Homophily/heterophily z-scores values are presented as a heatmap allowing a visual at-a-glance interpretation of results. AVAILABILITY AND IMPLEMENTATION: Tool's source code is available at https://github.com/cumbof/honto under the MIT license, installable as a package from PyPI (pip install honto) and conda-forge (conda install -c conda-forge honto), and has a wrapper for the Galaxy platform available on the official Galaxy ToolShed (Blankenberg et al., 2014) at https://toolshed.g2.bx.psu.edu/view/fabio/honto
Esclusione, identit\ue0 e differenza. Riflessioni su diritti e alterit\ue0
Il nucleo concettuale attorno a cui si addensano e confrontano
ricerche, studi e indagini all\u2019interno di questo
volume, \ue8 rappresentato dal rapporto che intercorre tra
identit\ue0 e differenza, rispetto a meccanismi di esclusione
e misconoscimento. Di fronte a nuove blindature
prodotte da processi migratori, specchio di trasformazioni
geopolitiche globali, ci si interroga su
come l\u2019alterit\ue0, nella sua complessa fenomenologia,
investa la sfera giuridica retroagendo sul tessuto politico-sociale.
L\u2019opera documenta gli esiti del Convegno internazionale
di studi \u201cAuschwitz. Prima e oltre\u201d promosso dall\u2019Universit\ue0
degli Studi di Macerata e dall\u2019Osservatorio
di Genere - Istituto storico della Resistenza di
Macerata, che ha messo al centro Auschwitz quale paradigma
di una cesura o spartiacque nella storia, divenuto nel
tempo memoria di come il progressivo sfaldarsi del
senso del limite possa preludere alla catastrofe. Su quell'evento a lungo irrappresentabile appare
possibile, e persino auspicabile, porsi domande in relazione
al moltiplicarsi nella contemporaneit\ue0 di quell\u2019esposizione alla morte degli altri \u2013 intesa sia come pericolo
che come espulsione o rifiuto \u2013 con lo sguardo rivolto a un passato che occorre continuare a narrare
Definitive experimental evidence for two-band superconductivity in MgB2
The superconducting gap of MgB2 has been studied by high-resolution
angle-resolved photoemission spectroscopy (ARPES). The momentum(k)-resolving
capability of ARPES enables us to identify the s- and p-orbital derived bands
predicted from band structure calculations and to successfully measure the
superconducting gap on each band. The results show that superconducting gaps
with values of 5.5 meV and 2.2 meV open on the s-band and the p-band,
respectively, but both the gaps close at the bulk transition temperature,
providing a definitive experimental evidence for the two-band superconductivity
in MgB2. The experiments validate the role of k-dependent electron-phonon
coupling as the origin of multiple-gap superconductivity in MgB2.Comment: PDF file onl
Tris(βâketoiminate) Aluminium(III) Compounds as Aluminium Oxide Precursors
Precursor design is the crucial step in tailoring the deposition profile towards a multitude of functional materials. Most commercially available aluminium oxide precursors require high processing temperatures (>500â°C). Herein, we report the tuning of the decomposition profile (200â350â°C) of a range of octahedrally coordinated tris(β-ketoiminate) aluminium complexes of the type [Al(MeCN(R)CHC=OMe)3], by varying the R substituents in the ligands. The complexes are derived from the reaction of trimethylamine alane (TMAA) and a series of N-substituted β-ketoiminate ligands (R-acnacH, R=Me, Et, iPr, Ph) with varying R-substituents sizes. When the more sterically encumbered ligand (R=Mes) was used, the Al atom became five-coordinate, therefore representing the threshold to octahedral coordination around the metal in these type of compounds, which, consequently, lead to a change of decomposition profile. The resulting compounds have been characterised by NMR spectroscopy, mass spectrometry, elemental analysis and single crystal X-ray diffraction. [Al(MeCN(Me)CHC=OMe)3] has been used as a single source precursor for the deposition of Al2O3. Thin films were deposited via aerosol assisted chemical vapour deposition (AACVD), with toluene as the solvent, and were analysed using SEM, EDX and XPS
Padrão de crescimento populacional dos perfilhos de Panicum maximum cv. Tanzânia.
DisponĂvel em: http://www.usp.br/siicusp/11osiicusp/index.htm. Acesso em: 10 de dez. 2003
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