514 research outputs found
Polimorfisme Gen Terkait Dengan Peningkatan Lipolisis Adiposum
Berbagai variasi genetik mempengaruhi lipolisis jaringan adiposum, suatu polimorfisme yang relatif umum seperti pada gen USF-1 dan gen AR (adrenoseptor). Polimorfisme gen USF-1 terkait dengan peningkatan kemampuan katekolamin untuk menstimulasi lipolisis pada sel-sel lemak, karena adanya peningkatan fungsi post-reseptor yang kemungkinan terjadi pada level protein kinase A yang melibatkan sub unit tipe 1 regulatori, sedangkan polimorfisme gen AR (adrenoseptor) ß2 dan ß3 terkait dengan sensitivitas reseptor yang berubah terhadap stimulasi agonis dan terhadap pengulangan (repeat) dinukleotida pada gen HSL (hormon-sensitive lipase) yang secara nyata menurunkan kemampuan katekolamin menstimulasi lipolisis
Low delta-V near-Earth asteroids: A survey of suitable targets for space missions
In the last decades Near-Earth Objects (NEOs) have become very important
targets to study, since they can give us clues to the formation, evolution and
composition of the Solar System. In addition, they may represent either a
threat to humankind, or a repository of extraterrestrial resources for suitable
space-borne missions. Within this framework, the choice of next-generation
mission targets and the characterisation of a potential threat to our planet
deserve special attention. To date, only a small part of the 11,000 discovered
NEOs have been physically characterised. From ground and space-based
observations one can determine some basic physical properties of these objects
using visible and infrared spectroscopy. We present data for 13 objects
observed with different telescopes around the world (NASA-IRTF, ESO-NTT, TNG)
in the 0.4 - 2.5 um spectral range, within the NEOSURFACE survey
(http://www.oa-roma.inaf.it/planet/NEOSurface.html). Objects are chosen from
among the more accessible for a rendez-vous mission. All of them are
characterised by a delta-V (the change in velocity needed for transferring a
spacecraft from low-Earth orbit to rendez-vous with NEOs) lower than 10.5 km/s,
well below the Solar System escape velocity (12.3 km/s). We taxonomically
classify 9 of these objects for the first time. 11 objects belong to the
S-complex taxonomy; the other 2 belong to the C-complex. We constrain the
surface composition of these objects by comparing their spectra with meteorites
from the RELAB database. We also compute olivine and pyroxene mineralogy for
asteroids with a clear evidence of pyroxene bands. Mineralogy confirms the
similarity with the already found H, L or LL ordinary chondrite analogues.Comment: 9 pages, 7 figures, to be published in A&A Minor changes by language
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Versatile hybrid acoustic micromixer with demonstration of circulating cell-free DNA extraction from sub-ml plasma samples
A low-cost and easy to implement acoustic micromixer compatible with multiple fabrication technologies that can provide efficient and vigorous mixing
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Liberatory School Counseling Practices to Promote Freedom Dreaming for Black Youth
The American School Counseling Association calls for professional school counselors to support the holistic development and success of all students. However, the field of school counseling is riddled with practices that have harmed and dehumanized Black students. For example, school counselors engage in practices (e.g., social–emotional learning and vocational guidance), which work to reinforce white supremacy and dehumanize Black students. Further, school counselors may also contribute to the ways that the basic and unique needs of Black students are overlooked, leading to the continued systemic adultification of Black students. What is needed is a radical imagination of school counseling, which centers on homeplace as the foundation in order to engage in freedom dreaming. In this article, the authors engage this radical imagination to detail an antiracist view of school counseling practice that embraces freedom dreaming and homeplace through healing and Indigenous educational practices, youth-led school counseling, and critical hip-hop practices to promote joy, creativity, power, love, resistance, and liberation
Simulation of a Diels-Alder Reaction on a Quantum Computer
The simulation of chemical reactions is an anticipated application of quantum
computers. Using a Diels-Alder reaction as a test case, in this study we
explore the potential applications of quantum algorithms and hardware in
investigating chemical reactions. Our specific goal is to calculate the
activation barrier of a reaction between ethylene and cyclopentadiene forming a
transition state. To achieve this goal, we use quantum algorithms for near-term
quantum hardware (entanglement forging and quantum subspace expansion) and
classical post-processing (many-body perturbation theory) in concert. We
conduct simulations on IBM quantum hardware using up to 8 qubits, and compute
accurate activation barriers in the reaction between cyclopentadiene and
ethylene by accounting for both static and dynamic electronic correlation. This
work illustrates a hybrid quantum-classical computational workflow to study
chemical reactions on near-term quantum devices, showcasing the potential of
quantum algorithms and hardware in accurately calculating activation barriers
A Semiparametric Bayesian Multivariate Model for Survival Probabilities After Acute Myocardial Infarction
In this work, a Bayesian semiparametric multivariate model is fitted to study data related to in-hospital and 60-day survival probabilities of patients admitted to a hospital with ST-elevation myocardial infarction diagnosis. We consider a hierarchical generalized linear model to predict survival probabilities and a process indicator (time of intervention). Poisson-Dirichlet process priors, generalizing the well-known Dirichlet process, are considered for modeling the random-effect distribution of the grouping factor which is the hospital of admission
The NEOShield-2 EU project: The Italian contribution
The NEOShield-2 (2015-2017) project has been recently approved by the European Commission in the framework of the Horizon 2020 programme with the aim i) to study specific technologies and instruments to conduct close approach missions to NEOs or to undertake mitigation demonstration, and ii) to acquire in-depth information of physical properties of the population of small NEOs (50-300 m), in order to design mitigation missions and assess the consequences of an impact on Earth. The Italian scientific community is widely involved in this project
Photometric survey of 67 near-Earth objects
Context. The near-Earth object (NEO) population is a window into the original conditions of the protosolar nebula, and has the potential to provide a key pathway for the delivery of water and organics to the early Earth. In addition to delivering the crucial ingredients for life, NEOs can pose a serious hazard to humanity since they can impact the Earth. To properly quantify the impact risk, physical properties of the NEO population need to be studied. Unfortunately, NEOs have a great variation in terms of mitigation-relevant quantities (size, albedo, composition, etc.) and less than 15% of them have been characterized to date. Aims. There is an urgent need to undertake a comprehensive characterization of smaller NEOs (D < 300 m) given that there are many more of them than larger objects; their small sizes make them intrinsically fainter and therefore harder to study. One of the main aims of the NEOShield-2 project (2015-2017), financed by the European Community in the framework of the Horizon 2020 program, is therefore to retrieve physical properties of a wide number of NEOs in order to design impact mitigation missions and assess the consequences of an impact on Earth. Methods. We carried out visible photometry of NEOs, making use of the DOLORES instrument at the Telescopio Nazionale Galileo (TNG, La Palma, Spain) in order to derive visible color indexes and the taxonomic classification for each target in our sample. Results. We attributed for the first time the taxonomical complex of 67 objects obtained during the first year of the project. While the majority of our sample belong to the S-complex, carbonaceous C-complex NEOs deserve particular attention. These NEOs can be located in orbits that are challenging from a mitigation point of view, with high inclination and low minimum orbit intersection distance (MOID). In addition, the lack of carbonaceous material we see in the small NEO population might not be due to an observational bias alone
Quantum chemistry simulation of ground- and excited-state properties of the sulfonium cation on a superconducting quantum processor
The computational description of correlated electronic structure, and
particularly of excited states of many-electron systems, is an anticipated
application for quantum devices. An important ramification is to determine the
dominant molecular fragmentation pathways in photo-dissociation experiments of
light-sensitive compounds, like sulfonium-based photo-acid generators used in
photolithography. Here we simulate the static and dynamical electronic
structure of the HS molecule, taken as a minimal model of a
triply-bonded sulfur cation, on a superconducting quantum processor of the IBM
Falcon architecture.
To this end, we combine a qubit reduction technique with variational and
diagonalization quantum algorithms, and use a sequence of error-mitigation
techniques. We compute dipole structure factors and partial atomic charges
along ground- and excited-state potential energy curves, revealing the
occurrence of homo- and heterolytic fragmentation. To the best of our
knowledge, this is the first simulation of a photo-dissociation reaction on a
superconducting quantum device, and an important step towards the computational
description of photo-dissociation by quantum computing algorithms.Comment: 12 pages, 7 figure
Subspace methods for electronic structure simulations on quantum computers
Quantum subspace methods (QSMs) are a class of quantum computing algorithms
where the time-independent Schrodinger equation for a quantum system is
projected onto a subspace of the underlying Hilbert space. This projection
transforms the Schrodinger equation into an eigenvalue problem determined by
measurements carried out on a quantum device. The eigenvalue problem is then
solved on a classical computer, yielding approximations to ground- and
excited-state energies and wavefunctions. QSMs are examples of hybrid
quantum-classical methods, where a quantum device supported by classical
computational resources is employed to tackle a problem. QSMs are rapidly
gaining traction as a strategy to simulate electronic wavefunctions on quantum
computers, and thus their design, development, and application is a key
research field at the interface between quantum computation and electronic
structure. In this review, we provide a self-contained introduction to QSMs,
with emphasis on their application to the electronic structure of molecules. We
present the theoretical foundations and applications of QSMs, and we discuss
their implementation on quantum hardware, illustrating the impact of noise on
their performance.Comment: 34 pages, 11 figure
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