740 research outputs found
Predicción in vivo de la composición de la canal: técnica de los ultrasonidos y puntuación de la condición corporal.
En una detallada monografÃa sobre la calidad de la canal ovina. Delfa (1992a) y Delfa el al.
(J 992a) exponÃan que la valoración de la composición de la canal, es decir, la determinación de la proporción de piezas que de ella se obtienen asà como de la cantidad absoluta o relativa del musculo. grasa y hueso que cada una de las piezas proporcionan y el reparto y distribución del
tejido adiposo en la canal. Son los criterios más importantes que dilucidan la calidad de las mismas
Geometrical bounds on irreversibility in open quantum systems
Clausius inequality has deep implications for reversibility and the arrow of
time. Quantum theory is able to extend this result for closed systems by
inspecting the trajectory of the density matrix on its manifold. Here we show
that this approach can provide an upper and lower bound to the irreversible
entropy production for open quantum systems as well. These provide insights on
the thermodynamics of the information erasure. Limits of the applicability of
our bounds are discussed, and demonstrated in a quantum photonic simulator
Bridging thermodynamics and metrology in non-equilibrium Quantum Thermometry
Single-qubit thermometry presents the simplest tool to measure the
temperature of thermal baths with reduced invasivity. At thermal equilibrium,
the temperature uncertainty is linked to the heat capacity of the qubit,
however the best precision is achieved outside equilibrium condition. Here, we
discuss a way to generalize this relation in a non-equilibrium regime, taking
into account purely quantum effects such as coherence. We support our findings
with an experimental photonic simulation.Comment: 7 pages, 4 figure
Volatiles and refratories in solar analogs: no terrestial planet connection
We have analysed very high-quality HARPS and UVES spectra of 95 solar
analogs, 24 hosting planets and 71 without detected planets, to search for any
possible signature of terrestial planets in the chemical abundances of volatile
and refractory elements with respect to the solar abundances. We demonstrate
that stars with and without planets in this sample show similar mean abundance
ratios, in particular, a sub-sample of 14 planet-host and 14 "single" solar
analogs in the metallicity range 0.14<[Fe/H]<0.36. In addition, two of the
planetary systems in this sub-sample, containing each of them a
super-Earth-like planet with masses in the range ~ 7-11 Earth masses, have
different volatile-to-refratory abundance ratios to what would be expected from
the presence of a terrestial planets. Finally, we check that after removing the
Galactic chemical evolution effects any possible difference in mean abundances,
with respect to solar values, of refratory and volatile elements practically
dissappears.Comment: 2 pages, 2 figures, to appear in the proceedings of the 276th IAU
Symposium "The Astrophysics of Planetary Systems
Interconnections between Content Knowledge and Pedagogical Content Knowledge of a University Lecturer in Linear Algebra
The aim of this study is to deepen our understanding of the practice of a lecturer in linear
algebra by exploring the connections he makes between his content knowledge and his pedagogical
content knowledge while working on the topic of matrices. Data were collected through video
recordings of his classes and semi-structured interviews, and were analysed with the Mathematics
Teacher’s Specialised Knowledge model. Instances of classroom performance, supported by the
teacher’s own affirmations, provided evidence relating to the categories comprising the model, and
enabled us to establish connections between the lecturer’s knowledge, his understanding of his
students’ learning capabilities, and his knowledge of teaching mathematics, which together account
for his classroom practice: the use of varied examples to introduce new content, the highlighting of
the most salient aspects of the topic, and alerts about potential errors and difficulties. The contribution
that these results could make to the training of university teachers, which would be done with the
knowledge of the areas of difficulty shown by the teacher in mind, could be used to deepen other
elements of their pedagogical content knowledge. The interconnections between areas of knowledge
identified by the study also serve to validate the usefulness of a theoretical model for studying
teachers’ knowledgeThis research was financed by the COIDESO research centre at the University of Huelva,
the Ministry of Science, Innovation and Universities of the Government of Spain (project: RTI2018-
096547-B-I00), and the research group DESYM (HUM-168
Post Quantum Cryptography from Mutant Prime Knots
By resorting to basic features of topological knot theory we propose a
(classical) cryptographic protocol based on the `difficulty' of decomposing
complex knots generated as connected sums of prime knots and their mutants. The
scheme combines an asymmetric public key protocol with symmetric private ones
and is intrinsecally secure against quantum eavesdropper attacks.Comment: 14 pages, 5 figure
Type Inference for Deadlock Detection in a Multithreaded Polymorphic Typed Assembly Language
We previously developed a polymorphic type system and a type checker for a
multithreaded lock-based polymorphic typed assembly language (MIL) that ensures
that well-typed programs do not encounter race conditions. This paper extends
such work by taking into consideration deadlocks. The extended type system
verifies that locks are acquired in the proper order. Towards this end we
require a language with annotations that specify the locking order. Rather than
asking the programmer (or the compiler's backend) to specifically annotate each
newly introduced lock, we present an algorithm to infer the annotations. The
result is a type checker whose input language is non-decorated as before, but
that further checks that programs are exempt from deadlocks
Design, Green Synthesis and Performance of L-Leucine-Molecularly Imprinted Polymers
The authors would like to acknowledge financial support from Fundação para a Ciência e a Tecnologia, Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES), Portugal, through projects PTDC/EQU-EQU/32473/2017, PTDC/MEC-ONC/29327/2017, and PTDC/QUI-QIN/30649/2017 (REALM). A.I.F. acknowledges her PhD grant (SFRH/BD/150696/2020) in the aim of the International Year of the Periodic Table─a protocol established between the Portuguese Chemical Society (SPQ) and the Portuguese Foundation for Science and Technology (FCT/MCTES). R.V. would like to acknowledge Individual Scientific Employment Stimulus (CEEC-IND), reference 2020.00377.CEECIND from the FCT/MCTES, Portugal. The Associate Laboratory Research Unit for Green Chemistry–Clean Technologies and Processes–LAQV-REQUIMTE is financed by national funds from FCT/MCTES (UIDB/50006/2020, UIDP/50006/2020, and UID/QUI/50006/2020) and cofinanced by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER–007265).Biopurification is a challenging and growing market. Despite great efforts in the past years, current purification strategies still lack specificity, efficiency, and cost-effectiveness. The development of more sustainable functional materials and processes needs to address pressing environmental goals, efficiency, scale-up, and cost. Herein, l-leucine (LEU)-molecularly imprinted polymers (MIPs), LEU-MIPs, are presented as novel biomolecular fishing polymers for affinity sustainable biopurification. Rational design was performed using quantum mechanics calculations and molecular modeling for selecting the most appropriate monomers. LEU-MIPs were synthesized for the first time by two different green approaches, supercritical carbon dioxide (scCO2) technology and mechanochemistry. A significant imprinting factor of 12 and a binding capacity of 27 mg LEU/g polymer were obtained for the LEU-MIP synthesized in scCO2 using 2-vinylpyridine as a functional monomer, while the LEU-MIP using acrylamide as a functional monomer synthesized by mechanochemistry showed an imprinting factor of 1.4 and a binding capacity of 18 mg LEU/g polymer, both systems operating at a low binding concentration (0.5 mg LEU/mL) under physiological conditions. As expected, at a higher concentration (1.5 mg LEU/mL), the binding capacity was considerably increased. Both green technologies show high potential in obtaining ready-to-use, stable, and low-cost polymers with a molecular recognition ability for target biomolecules, being promising materials for biopurification processes.publishersversionpublishe
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