3,075 research outputs found
Astrophysical and Cosmological Tests of Quantum Theory
We discuss several proposals for astrophysical and cosmological tests of
quantum theory. The tests are motivated by deterministic hidden-variables
theories, and in particular by the view that quantum physics is merely an
effective theory of an equilibrium state. The proposed tests involve searching
for nonequilibrium violations of quantum theory in: primordial inflaton
fluctuations imprinted on the cosmic microwave background, relic cosmological
particles, Hawking radiation, photons with entangled partners inside black
holes, neutrino oscillations, and particles from very distant sources.Comment: 25 pages. Amendment to section 7. Contribution to: "The Quantum
Universe", special issue of Journal of Physics A, dedicated to Prof. G.-C.
Ghirardi on the occasion of his seventieth birthda
Effect of metal clusters on the swelling of gold-fluorocarbon-polymer composite films
We have investigated the phenomenon of swelling due to acetone diffusion in
fluorocarbon polymer films doped with different gold concentrations below the
percolation threshold. The presence of the gold clusters in the polymer is
shown to improve the mixing between the fluorocarbon polymer and the acetone,
which is not a good solvent for this kind of polymers. In order to explain the
experimental results the stoichiometry and the morphology of the polymer--metal
system have been studied and a modified version of the Flory--Huggins model has
been developed
Komunikasi Persuasif PT. Pegadaian (Persero) Dalam Meningkatkan Jumlah Nasabah Tabungan Emas, Cabang Panam Kota Pekanbaru Provinsi Riau
Gold is one asset because gold has a value that tends to be stable even will give advantage in time. Therefore some people make gold as a means to save.PT. Pegadaian (Persero) is one of the state-owned companies in Indonesia. The success of PT. Pegadaian can be seen from the many branches of each region in Indonesia and various product service programs that have been launched the PT. Pegadaian, one of which is gold saving. This program invites people to learn to invest where the investment is done by saving based on the provisions of at least Rp.5.000,00 then the customer has been getting gold.PT. Pegadaian (Persero) is usually synonymous with service to the community, especially the middle class down, therefore, the gold savings that issued PT. Pegadaian (Persero) is a program that is addressed to the lower middle class. However, over time and seen from the increasing number of customers saving gold, the gold savings developed into a program that is not only aimed at the middle class but also aimed at the general community. Until now, gold saving has been run throughout PT. Pegadaian Branch and Unit as in PT. Pegadaian Branch of Pekanbaru City Panam Riau Province.The results of this study explain that the increasing number of customers saving gold at PT. Pegadaian (Persero) Pekanbaru Panam Branch, Riau Province, is due to the efforts of PT. Pegadaian in recruiting potential customers. One of the efforts and ways to do is to run a process of persuasive communication. The success of the persuasive process can be seen based on the characteristics of communicators PT. Pegadaian (Persero) in recruiting prospective customers, the form of persuasive message submitted by PT. Pegadaian (Persero) in recruiting potential customers and communication media used by PT. Pegadaian (Persero) in recruiting potential customers
New accessibility measures based on unconventional big data sources
In health econometric studies we are often interested in quantifying aspects
related to the accessibility to medical infrastructures. The increasing
availability of data automatically collected through unconventional sources
(such as webscraping, crowdsourcing or internet of things) recently opened
previously unconceivable opportunities to researchers interested in measuring
accessibility and to use it as a tool for real-time monitoring, surveillance
and health policies definition. This paper contributes to this strand of
literature proposing new accessibility measures that can be continuously feeded
by automatic data collection. We present new measures of accessibility and we
illustrate their use to study the territorial impact of supply-side shocks of
health facilities. We also illustrate the potential of our proposal with a case
study based on a huge set of data (related to the Emergency Departments in
Milan, Italy) that have been webscraped for the purpose of this paper every 5
minutes since November 2021 to March 2022, amounting to approximately 5 million
observations
Prediction of Human Phenotype Ontology terms by means of hierarchical ensemble methods
Background The prediction of human gene–abnormal phenotype associations is a
fundamental step toward the discovery of novel genes associated with human
disorders, especially when no genes are known to be associated with a specific
disease. In this context the Human Phenotype Ontology (HPO) provides a
standard categorization of the abnormalities associated with human diseases.
While the problem of the prediction of gene–disease associations has been
widely investigated, the related problem of gene–phenotypic feature (i.e., HPO
term) associations has been largely overlooked, even if for most human genes
no HPO term associations are known and despite the increasing application of
the HPO to relevant medical problems. Moreover most of the methods proposed in
literature are not able to capture the hierarchical relationships between HPO
terms, thus resulting in inconsistent and relatively inaccurate predictions.
Results We present two hierarchical ensemble methods that we formally prove to
provide biologically consistent predictions according to the hierarchical
structure of the HPO. The modular structure of the proposed methods, that
consists in a “flat” learning first step and a hierarchical combination of the
predictions in the second step, allows the predictions of virtually any flat
learning method to be enhanced. The experimental results show that
hierarchical ensemble methods are able to predict novel associations between
genes and abnormal phenotypes with results that are competitive with state-of-
the-art algorithms and with a significant reduction of the computational
complexity. Conclusions Hierarchical ensembles are efficient computational
methods that guarantee biologically meaningful predictions that obey the true
path rule, and can be used as a tool to improve and make consistent the HPO
terms predictions starting from virtually any flat learning method. The
implementation of the proposed methods is available as an R package from the
CRAN repository
Carbon balance assessment of a natural steppe of southern Siberia by multiple constraint approach
Steppe ecosystems represent an interesting case in which the assessment of carbon balance may be performed through a cross validation of the eddy covariance measurements against ecological inventory estimates of carbon exchanges (Ehman et al., 2002; Curtis et al., 2002). <br><br> Indeed, the widespread presence of ideal conditions for the applicability of the eddy covariance technique, as vast and homogeneous grass vegetation cover over flat terrains (Baldocchi, 2003), make steppes a suitable ground to ensure a constrain to flux estimates with independent methodological approaches. <br><br> We report about the analysis of the carbon cycle of a true steppe ecosystem in southern Siberia during the growing season of 2004 in the framework of the TCOS-Siberia project activities performed by continuous monitoring of CO<sub>2</sub> fluxes at ecosystem scale by the eddy covariance method, fortnightly samplings of phytomass, and ingrowth cores extractions for NPP assessment, and weekly measurements of heterotrophic component of soil CO<sub>2</sub> effluxes obtained by an experiment of root exclusion. <br><br> The carbon balance of the monitored natural steppe was, according to micrometeorological measurements, a sink of carbon of 151.7±36.9 g C m<sup>&minus;2</sup>, cumulated during the growing season from May to September. This result was in agreement with the independent estimate through ecological inventory which yielded a sink of 150.1 g C m<sup>&minus;2</sup> although this method was characterized by a large uncertainty (±130%) considering the 95% confidence interval of the estimate. Uncertainties in belowground process estimates account for a large part of the error. Thus, in particular efforts to better quantify the dynamics of root biomass (growth and turnover) have to be undertaken in order to reduce the uncertainties in the assessment of NPP. This assessment should be preferably based on the application of multiple methods, each one characterized by its own merits and flaws
Existential Contextuality and the Models of Meyer, Kent and Clifton
It is shown that the models recently proposed by Meyer, Kent and Clifton
(MKC) exhibit a novel kind of contextuality, which we term existential
contextuality. In this phenomenon it is not simply the pre-existing value but
the actual existence of an observable which is context dependent. This result
confirms the point made elsewhere, that the MKC models do not, as the authors
claim, ``nullify'' the Kochen-Specker theorem. It may also be of some
independent interest.Comment: Revtex, 7 pages, 1 figure. Replaced with published versio
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