177 research outputs found
Teacher's guide book for primary and secondary school
There is an urgent need for collective action to mitigate the consequences of climate change and adapt to unavoidable changes. The complexity of climate change issues can pose educational challenges. Nonetheless, education has a key role to play in ensuring that younger generations have the required knowledge and skills to understand issues surrounding climate change, to avoid despair, to take action, and to be prepared to live in a changing world.
The Office for Climate Education (OCE) was founded in 2018 to promote strong international cooperation between scientific organisations, educational institutions and NGOs. The overall aim of the OCE is to ensure that the younger generations of today and tomorrow are educated about climate change. Teachers have a key role to play in their climate education and it is essential that they receive sufficient support to enable them to implement effective lessons on climate change. The OCE has developed a range of educational resources and professional development modules to support them in teaching about climate change with active pedagogy
Interstellar H2 toward HD 37903
We present an analysis of interstellar H2 toward HD 37903, which is a hot, B
1.5 V star located in the NGC 2023 reflection nebula. Meyer et al. (2001) have
used a rich spectrum of vibrationally excited H2 observed by the HST to
calculate a model of the interstellar cloud toward HD 37903. We extend Mayer's
analysis by including the v"=0 vibrational level observed by the FUSE
satellite.
The T01 temperature should not be interpreted as a rotational temperature,
but rather as a temperature of thermal equilibrium between the ortho and para
H2. The ortho to para H2 ratio is lower for collisionally populated levels than
for the levels populated by fluorescence.
The PDR model of the cloud located in front of HD 37903 points to a gas
temperature Tkin=110-377 K, hydrogen density nH=1874-544 cm^-3 and the
star-cloud distance of 0.45 pc
Changement climatique et éducation
Education dealing with climate change is part of the UNFCCC Paris Agreement ratified in 2016. Education is precious to act on a broad scale on people’s behavior and society choices. It is also a demand from the youth who, more than others, is facing a worrying future, but can be helped for a mobilization of energies. Numerous initiatives emerge to implement it, while its systemic and interdisciplinary character requests a significant evolution of school’s curricula. The role of teachers is crucial and accompanying them essential. We therefore consider critical to propose pedagogical resources, which are based upon the best current knowledge on climate, i.e. the reports from the Intergovernmental Panel on Climate Change (IPCC)
Changement climatique et éducation
Education dealing with climate change is part of the UNFCCC Paris Agreement ratified in 2016. Education is precious to act on a broad scale on people’s behavior and society choices. It is also a demand from the youth who, more than others, is facing a worrying future, but can be helped for a mobilization of energies. Numerous initiatives emerge to implement it, while its systemic and interdisciplinary character requests a significant evolution of school’s curricula. The role of teachers is crucial and accompanying them essential. We therefore consider critical to propose pedagogical resources, which are based upon the best current knowledge on climate, i.e. the reports from the Intergovernmental Panel on Climate Change (IPCC)
The Spitzer c2d Survey of Nearby Dense Cores: Jet and Molecular Outflow Associated with a YSO in core A of L1251
A long infrared jet has been discovered by the Spitzer c2d legacy program in
core A of L1251. It is associated with a very embedded Class 0 object with an
accretion luminosity of about 0.9 Lsun derived by radiative transfer model
fitting to the observed SED. Comparing the observed IRAC colors along the
infrared jet with those calculated from a model of an admixture of gas with a
power-law temperature distribution indicates that the jet is possibly created
by a paraboloidal bow shock propagating into the ambient medium of n(H_2)=10^5
cm^{-3}. In addition, the variation of the power-law index along the jet
suggests that the portion of hot gas decreases with distance from the jet
engine. The molecular outflow in this region has been mapped for the first time
using CO data. From the calculated outflow momentum flux, a very strong lower
limit to the average accretion luminosity is 3.6 sin i/cos^3 i Lsun, indicative
of a decrease in the accretion rate with time.Comment: To appear in ApJ Letter
Shocked Molecular Hydrogen in the 3C 326 Radio Galaxy System
The Spitzer spectrum of the giant FR II radio galaxy 3C 326 is dominated by
very strong molecular hydrogen emission lines on a faint IR continuum. The H2
emission originates in the northern component of a double-galaxy system
associated with 3C 326. The integrated luminosity in H2 pure-rotational lines
is 8.0E41 erg/s, which corresponds to 17% of the 8-70 micron luminosity of the
galaxy. A wide range of temperatures (125-1000 K) is measured from the H2 0-0
S(0)-S(7) transitions, leading to a warm H2 mass of 1.1E9 Msun. Low-excitation
ionic forbidden emission lines are consistent with an optical LINER
classification for the active nucleus, which is not luminous enough to power
the observed H2 emission. The H2 could be shock-heated by the radio jets, but
there is no direct indication of this. More likely, the H2 is shock-heated in a
tidal accretion flow induced by interaction with the southern companion galaxy.
The latter scenario is supported by an irregular morphology, tidal bridge, and
possible tidal tail imaged with IRAC at 3-9 micron. Unlike ULIRGs, which in
some cases exhibit H2 line luminosities of comparable strength, 3C 326 shows
little star-formation activity (~0.1 Msun/yr). This may represent an important
stage in galaxy evolution. Starburst activity and efficient accretion onto the
central supermassive black hole may be delayed until the shock-heated H2 can
kinematically settle and coolComment: 27 pages, 7 figures, accepted for publication in the Astrophysical
Journa
Spitzer and near-infrared observations of a new bi-polar protostellar outflow in the Rosette Molecular Cloud
We present and discuss \emph{Spitzer} and near-infrared H observations
of a new bi-polar protostellar outflow in the Rosette Molecular Cloud. The
outflow is seen in all four IRAC bands and partially as diffuse emission in the
MIPS 24 m band. An embedded MIPS 24 m source bisects the outflow and
appears to be the driving source. This source is coincident with a dark patch
seen in absorption in the 8 m IRAC image. \emph{Spitzer} IRAC color
analysis of the shocked emission was performed from which thermal and column
density maps of the outflow were constructed. Narrow-band near-infrared (NIR)
images of the flow reveal H emission features coincident with the high
temperature regions of the outflow. This outflow has now been given the
designation MHO 1321 due to the detection of NIR H features. We use these
data and maps to probe the physical conditions and structure of the flow.Comment: Accepted for publication in The Astrophysical Journa
Paraoxonases-2 and -3 Are Important Defense Enzymes against Pseudomonas aeruginosa Virulence Factors due to Their Anti-Oxidative and Anti-Inflammatory Properties
The pathogen Pseudomonas aeruginosa causes serious damage in immunocompromised patients by secretion of various virulence factors, among them the quorum sensing N-(3-oxododecanoyl)-L-homoserine lactone (3OC12) and the redox-active pyocyanin (PCN). Paraoxonase-2 (PON2) may protect against P. aeruginosa infections, as it efficiently inactivates 3OC12 and diminishes PCN-induced oxidative stress. This defense could be circumvented because 3OC12 mediates intracellular Ca2+-rise in host cells, which causes rapid inactivation and degradation of PON2. Importantly, we recently found that the PON2 paralogue PON3 prevents mitochondrial radical formation. Here we investigated its role as additional potential defense mechanism against P. aeruginosa infections. Our studies demonstrate that PON3 diminished PCN-induced oxidative stress. Moreover, it showed clear anti-inflammatory potential by protecting against NF-κB activation and IL-8 release. The latter similarly applied to PON2. Furthermore, we observed a Ca2+-mediated inactivation and degradation of PON3, again in accordance with previous findings for PON2. Our results suggest that the anti-oxidative and anti-inflammatory functions of PON2 and PON3 are an important part of our innate defense system against P. aeruginosa infections. Furthermore, we conclude that P. aeruginosa circumvents PON3 protection by the same pathway as for PON2. This may help identifying underlying mechanisms in order to sustain the protection afforded by these enzymes
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