151 research outputs found
Laboratory thermal conductivity measurements on gravel sample
No full textModern Ground Source Heat Pumps (GSHPs) systems must be designed by taking into account the ground thermal properties, in order to properly plan the capability of the heat pumps to transfer calories through the Ground Source Heat Exchangers (GSHE) to the subsoil (and vice versa). As a result, in order to properly plan the best fitting Heating, Ventilation
and Air Conditioning (HVAC) systems, designers need to couple the energy building loads requirements to the ground thermal properties. Usually, some available information about the geological stratigraphy around the GSHE and soils’ thermal properties bibliography data could provide the preliminary estimation of the main parameters to proper design the GSHP with the related GSHE. On the other hands, alluvial plains and valley floors usually host most of the urban areas and anthropic activities such as cities, commercial districts and industrial region. As a result, for HVAC applications, thermal properties of alluvial materials should be studied more in detail since they have quite a considerable impact on the HVAC efficiency. Gravel thermal properties have been detected by the means of a guarded hot plate Taurus Instruments TLP 800, where some changes in the setup have been made in order
to finalize the thermal measurements
Renormalized perturbation theory at field-level: the LSS bootstrap in GridSPT
No full textWe present a first step toward field-level cosmological inference beyond the standard ACDM model, focusing on optimizing precision tests in the nonlinear regime of large-scale structure (LSS). As an illustrative case, we study the model-independent "bootstrap" coefficient of the second-order perturbation theory (PT) kernel for matter in real space, which we use as a proxy for new physics effects in the nonlinear sector. We discuss in details the ultraviolet (UV) cutoff dependence induced by discretizing fields on a grid, which requires proper renormalization to eliminate grid artifacts. We formulate a Wilsonian perturbative framework in which the evolution from a UV theory defined at a high cutoff Aug down to lower cutoffs is computed analytically, even beyond the validity of a derivative expansion. Within this framework, we develop an extended version of the GridSPT code incorporating the bootstrap parameterization and demonstrate how cutoff-independent predictions can be achieved through the inclusion of appropriate counterterms. We validate our approach at third-and fifth-order in PT, emphasizing the importance of higher-derivative contributions for unbiased parameter extraction. Our framework is readily extendable to biased tracers and redshift-space distortions
Clustering of binary black hole mergers: a detailed analysis of the EAGLE+MOBSE simulation
No full textWe perform a detailed study of the cosmological bias of gravitational gave
(GW) events produced by binary black hole mergers (BBHM). We start from a BBHM
distribution modeled inside the EAGLE hydrodyamical simulation using the
population synthesis code MOBSE. We then compare our findings with predictions
from different Halo Occupation Distribution (HOD) prescriptions and find
overall agreement, provided that the modeled properties of host galaxies and
halos in the semi-analytical treatment match those in the simulations. By
highlighting the sources of these discrepancies, we provide the stepping stone
to build future more robust models that prevent the shortcoming of both
simulation-based and analytical models. Finally, we train a neural network to
build a simulation-based HOD and perform feature importance analysis to gain
intuition on which host halo/galaxy parameters are the most relevant in
determining the actual distribution and power spectrum of BBHM. We find that
the distribution of BBHM in a galaxy does not only depend on its size, star
formation rate and metallicity, but also by its kinetic state
Studying the effects of natural extracts with metabolomics: A longitudinal study on the supplementation of healthy rats with Polygonum cuspidatum Sieb. et Zucc
No full textBackground A longitudinal study was performed to evaluate the effects of Polygonum cuspidatum extract (standardized at 20% resveratrol) supplementation on healthy rats. The effects were explored by monitoring urinary metabolome changes using UPLC-HRMS and 1H NMR-based approaches. The aim of the study was to explore the effects of P. cuspidatum supplementation on a healthy animal model using metabolomics, in order to determine possible modes of action and obtain information on bioactivity. Methods Healthy Sprague-Dawley rats were orally supplemented with 100 mg/kg of dried P. cuspidatum extract for 49 days and 24-h urinary outputs were collected. Samples were analysed by untargeted UPLC-HRMS and 1H NMR approaches and the obtained data sets were modelled by an adaptation of post-transformation of PLS2 to longitudinal studies. Putative markers were discovered by a stability selection procedure and specific oxidative stress markers were monitored by a targeted HPLC–MS/MS analysis to assess the in vivo antioxidant activity of P. cuspidatum extract. Results UPLC-HRMS and 1H NMR platforms showed two different but complementary patterns of metabolites describing the changes ascribable to P. cuspidatum supplementation and using both approaches, a comprehensive resveratrol metabolism and urinary excretion could be observed. Markers of P. cuspidatum supplementation effects identified by UPLC-HRMS were mainly related to its antioxidant activity and to a possible “adaptogenic” activity. Urinary changes observed by 1H NMR were mainly related to energy metabolism. UPLC-HRMS and 1H NMR metabolomics approaches allowed the effects of a prolonged supplementation with P. cuspidatum on healthy rats to be observed. The statistical models built from both data sets showed metabolic changes in urines related to rat aging
Constraining Cycle Alternations in Model Checking for Interval Temporal Logic
No full textModel checking is one of the most successful techniques in system verification. While a variety of methods and tools exist to check properties expressed in point-based temporal logics, like LTL and CTL, model checking for interval temporal logic has entered the research agenda only very recently. In previous work, we devised a non-elementary model checking procedure for Halpern and Shoham's modal logic of time intervals, interpreted over finite Kripke structures, and an EXPSPACE algorithm for two meaningful fragments of it. In this paper, we show that the latter algorithm can be suitably tailored in order to check a subset of the computations of a system, that satisfy a given bound on the number of cycle alternations, by making use of a polynomial (instead of exponential) working space. We also prove that such a revised algorithm turns out to be complete for Kripke structures whose strongly connected components are simple cycle
Laboratory Measurements of Gravel Thermal Conductivity: An Update Methodological Approach
No full textDirect measurements of gravel thermal properties are usually quite challenging to be performed in laboratory, due to the very coarse sediments size. As a consequence, the reference thermal values provided by literature for gravels are quite limited and dispersed. A guarded hot plate Taurus Instruments TLP 800, usually used for measuring the thermal conductivity of buildings materials, was slightly modified in order to measure the thermal conductivity of some gravel samples. The tests were performed both in dry and wet conditions. The paper presents the first obtained results
Recuperando a los Peron: Posmodemidad e intertextualidad en dos obras de Tomas Eloy Martinez
No full textRecent history has been the central theme of Argentinean writer Tomas Eloy Martinez. In his two most recognized novels, La novela de Peron (1985) and Santa Evita (1995), he revisits the Peronist period in Argentinean history and attempts to re-write and re-signify traditional accounts of that history while presenting what he hopes is a more balanced interpretation of the Perons and their place in the nation\u27s history.
The present dissertation analyses how Martinez uses numerous postmodern narrative strategies such as metafiction, parody, and intertextuality to carry out his revisionist project in the above-mentioned novels. As a point of departure, the dissertation examines the author\u27s critical attitude towards historiography and his skepticism on how history has been represented in his country. Secondly, it studies the transgression of boundaries among literary genres which helps the author represent the Perons in a multifaceted and eclectic way. Through metafiction, the author shares the challenges he faces in the construction of his work, helps the reader follow the storyline, and present information that comes from the non-fictional world.
This dissertation also explains how Martinez uses parody in La novela de Peron to deconstruct the idealized version of hi story represented in Peron\u27s Las memorias del General. Of special note is the fact that intertextuality is the most used technique in both novels; indeed, Martinez enters in dialogue with a wide variety of literary sources to support his views on historiography and to bring into question the traditional portrayal of both Peron and Evita in Argentina and in Latin American history.
This dissertation concludes that Martinez\u27s two works with the current of postmodern novels which Linda Hutcheon has described as Historiographic Metafiction. That is to say, both novels are intensely self-reflexive and treat historiography as closely-related genres. In fact, Martinez\u27s novels are presented as an alternative to historical accounts of the past. For Martinez, through imagination one can speculate about what might have happened in those mysteries left unexplained by official history and the passing of time. With the diverse array of evidence presented in the novels, the reader is challenged to reevaluate the Perons legacy, a legacy which according to our reading of Martinez can be summarized in two words: authoritarianism and corruption
Constraining Primordial Non-Gaussianity from Large Scale Structure with the Wavelet Scattering Transform
No full textInternational audienceWe investigate the Wavelet Scattering Transform (WST) as a tool for the study of Primordial non-Gaussianity (PNG) in Large Scale Structure (LSS), and compare its performance with that achievable via a joint analysis with power spectrum and bispectrum (P+B). We consider the three main primordial bispectrum shapes - local, equilateral and orthogonal - and produce Fisher forecast for the corresponding fNL amplitude parameters, jointly with standard cosmological parameters. We analyze simulations from the publicly available "Quijote" and "Quijote-png" N-body suites, studying both the dark matter and halo fields. We find that the WST outperforms the power spectrum alone on all parameters, both on the fNL's and on cosmological ones. In particular, on fNL_loc for halos, the improvement is about 27%. When B is combined with P, halo constraints from WST are weaker for fNL_loc (at ~ 15% level), but stronger for fNL_eq (~ 25%) and fNL_ortho (~ 28%). Our results show that WST, both alone and in combination with P+B, can improve the extraction of information on PNG from LSS data over the one attainable by a standard P+B analysis. Moreover, we identify a class of WST in which the origin of the extra information on PNG can be cleanly isolated
Thermography for assessing the thermal performance of innovative geopolymeric radiant panels
No full textOne of the last scientific activities of Ermanno Grinzato was the research on radiant heating and cooling systems. In addition to providing a novel view for thermal and thermographic testing of these systems, he had foreseen the importance of using efficient and sustainable materials. Firstly, this work introduces the issue of testing radiant heating and cooling systems and the arising interest in geopolymers. Afterwards, the synergy between these two research fields is highlighted by the realisation and testing of a novel geopolymeric panel
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