189 research outputs found
The Challenges and Rewards of Running a Geospace Environment Modeling Challenge
Geospace Environment Modeling (GEM) is a community-driven, National Science Foundation-sponsored research program investigating the physics of the Earth's magnetosphere and its coupling to the solar wind and the atmosphere. This commentary provides an introduction to a Special Issue collating recent studies related to a GEM Challenge on kinetic plasma processes in the dayside magnetosphere during southward interplanetary magnetic field conditions. We also recount our experiences of organizing such a collaborative activity, where modelers and observers compare their results, that is, of the human side of bringing researchers together. We give suggestions on planning, managing, funding, and documenting these activities, which provide valuable opportunities to advance the field.Plain Language Summary Geospace Environment Modeling (GEM) is a community-driven, National Science Foundation-sponsored research program investigating the physics of the Earth's magnetosphere and its coupling to the solar wind and the atmosphere. An integral part of the program is the so-called "Challenges", which bring people together to compare models and observations in order to advance our understanding of the near-Earth space environment. This commentary provides an introduction to a Special Issue collating recent studies related to one such collaborative effort. We also share our experiences as early-career scientists organizing such an activity, to aid those who might take part in such endeavors in the future. We give suggestions on planning, managing, funding, and documenting the activities
Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets
The current progress in the detection of terrestrial type exoplanets has
opened a new avenue in the characterization of exoplanetary atmospheres and in
the search for biosignatures of life with the upcoming ground-based and space
missions. To specify the conditions favorable for the origin, development and
sustainment of life as we know it in other worlds, we need to understand the
nature of astrospheric, atmospheric and surface environments of exoplanets in
habitable zones around G-K-M dwarfs including our young Sun. Global environment
is formed by propagated disturbances from the planet-hosting stars in the form
of stellar flares, coronal mass ejections, energetic particles, and winds
collectively known as astrospheric space weather. Its characterization will
help in understanding how an exoplanetary ecosystem interacts with its host
star, as well as in the specification of the physical, chemical and biochemical
conditions that can create favorable and/or detrimental conditions for
planetary climate and habitability along with evolution of planetary internal
dynamics over geological timescales. A key linkage of (astro) physical,
chemical, and geological processes can only be understood in the framework of
interdisciplinary studies with the incorporation of progress in heliophysics,
astrophysics, planetary and Earth sciences. The assessment of the impacts of
host stars on the climate and habitability of terrestrial (exo)planets will
significantly expand the current definition of the habitable zone to the
biogenic zone and provide new observational strategies for searching for
signatures of life. The major goal of this paper is to describe and discuss the
current status and recent progress in this interdisciplinary field and to
provide a new roadmap for the future development of the emerging field of
exoplanetary science and astrobiology.Comment: 206 pages, 24 figures, 1 table; Review paper. International Journal
of Astrobiology (2019
Universal Vectorial and Ultrasensitive Nanomechanical Force Field Sensor
Miniaturization of force probes into nanomechanical oscillators enables
ultrasensitive investigations of forces on dimensions smaller than their
characteristic length scale. Meanwhile it also unravels the force field
vectorial character and how its topology impacts the measurement. Here we
expose an ultrasensitive method to image 2D vectorial force fields by
optomechanically following the bidimensional Brownian motion of a singly
clamped nanowire. This novel approach relies on angular and spectral tomography
of its quasi frequency-degenerated transverse mechanical polarizations:
immersing the nanoresonator in a vectorial force field does not only shift its
eigenfrequencies but also rotate eigenmodes orientation as a nano-compass. This
universal method is employed to map a tunable electrostatic force field whose
spatial gradients can even take precedence over the intrinsic nanowire
properties. Enabling vectorial force fields imaging with demonstrated
sensitivities of attonewton variations over the nanoprobe Brownian trajectory
will have strong impact on scientific exploration at the nanoscale
Cultivating a Culture of Inclusivity in Heliophysics
A large number of heliophysicists from across career levels, institution types, and job titles came together to support a poster at Heliophysics 2050 and the position papers for the 2024 Heliophysics decadal survey titled “Cultivating a Culture of Inclusivity in Heliophysics,” “The Importance of Policies: It’s not just a pipeline problem,” and “Mentorship within Heliophysics.” While writing these position papers, the number of people who privately shared disturbing stories and experiences of bullying and harassment was shocking. The number of people who privately expressed how burned out they were was staggering. The number of people who privately spoke about how they considered leaving the field for their and their family’s health was astounding. And for as much good there is in our community, it is still a toxic environment for many. If we fail to do something now, our field will continue to suffer. While acknowledging the ongoing growth that we as individuals must work toward, we call on our colleagues to join us in working on organizational, group, and personal levels toward a truly inclusive culture, for the wellbeing of our colleagues and the success of our field. This work includes policies, processes, and commitments to promote: accountability for bad actors; financial security through removing the constant anxiety about funding; prioritization of mental health and community through removing constant deadlines and constant last-minute requests; a collaborative culture rather than a hyper-competitive one; and a community where people can thrive as whole persons and do not have to give up a healthy or well-rounded life to succeed
Activation of NF-kB Pathway by Virus Infection Requires Rb Expression
The retinoblastoma protein Rb is a tumor suppressor involved in cell cycle control, differentiation, and inhibition of oncogenic transformation. Besides these roles, additional functions in the control of immune response have been suggested. In the present study we investigated the consequences of loss of Rb in viral infection. Here we show that virus replication is increased by the absence of Rb, and that Rb is required for the activation of the NF-kB pathway in response to virus infection. These results reveal a novel role for tumor suppressor Rb in viral infection surveillance and further extend the concept of a link between tumor suppressors and antiviral activity
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