2,537 research outputs found
Worldwide analysis of crimes by the traces of their online media coverage: the case of jewellery store robberies
This empirical study aims to determine whether online media coverage can be used to gather intelligence on specific crimes worldwide. The quality of online news is evaluated as an indicator of the worldwide distribution of jewelry store robberies. This phenomenon was selected because evaluating the risk of criminal events at the global level is a challenge for private companies, who need to settle and prioritize protection strategies to determine the actual risk within each country. Online media coverage is thus scrutinized for its ability to reveal spatiotemporal trends of this phenomenon. Based upon a dataset of online news gathered between 2015 and 2017 from the news aggregator website EMM (Europa Media Monitor – NewsBrief), the results show that online news may be a cost-effective method to analyze risks worldwide — though a cross-check with different data sources is still necessary to validate its accuracy. The developed approach shows that (1) while a multilingual approach is required, (2) cases can be detected and automatically classified with good accuracy; (3) moreover, dates and countries of published news articles are generally reliable indicators of the actual times and places of the events, which reduce the need for complex text analysis methods. This study demonstrates how a simple monitoring approach can be used to support the worldwide spatiotemporal analysis of serious crimes such as jewelry store robberies
Isotopic Composition of Fragments in Nuclear Multifragmentation
The isotope yields of fragments, produced in the decay of the quasiprojectile
in Au+Au peripheral collisions at 35 MeV/nucleon and those coming from the
disassembly of the unique source formed in Xe+Cu central reactions at 30
MeV/nucleon, were measured. We show that the relative yields of neutron-rich
isotopes increase with the excitation energy in multifragmentation reaction. In
the framework of the statistical multifragmentation model which fairly well
reproduces the experimental observables, this behaviour can be explained by
increasing N/Z ratio of hot primary fragments, that corresponds to the
statistical evolution of the decay mechanism with the excitation energy: from a
compound-like decay to complete multifragmentation.Comment: 10 pages. 4 Postscript figures. Submitted to Physical Review C, Rapid
Communicatio
Negative heat capacity in the critical region of nuclear fragmentation: an experimental evidence of the liquid-gas phase transition
An experimental indication of negative heat capacity in excited nuclear
systems is inferred from the event by event study of energy fluctuations in
quasi-projectile sources formed in collisions at 35 A.MeV. The
excited source configuration is reconstructed through a calorimetric analysis
of its de-excitation products. Fragment partitions show signs of a critical
behavior at about 5 A.MeV excitation energy. In the same energy range the heat
capacity shows a negative branch providing a direct evidence of a first order
liquid gas phase transition.Comment: 4 Postscript figures, submitted to Phys. Rev. Lett. on 14-apr-199
Thermodynamical features of multifragmentation in peripheral Au + Au Collisions at 35 A.MeV
The distribution of fragments produced in events involving the
multifragmentation of excited sources is studied for peripheral Au + Au
reactions at 35 A.MeV.
The Quasi-Projectile has been reconstructed from its de-excitation products.
An isotropic emission in its rest frame has been observed, indicating that an
equilibrated system has been formed. The excitation energy of the
Quasi-Projectile has been determined via calorimetry.
A new event by event effective thermometer is proposed based on the energy
balance. A peak in the energy fluctuations is observed related to the heat
capacity, suggesting that the system undergoes a liquid-gas type phase
transition at an excitation energy about 5 A.MeV and a temperature 4 - 6 MeV,
dependent on the freeze-out hypothesis. By analyzing different regions of the
Campi-plot, the events associated with the liquid and gas phases as well as the
critical region are thermodynamically characterized.
The critical exponents, tau, beta,gamma, extracted from the high moments of
the charge distribution are consistent with a liquid-gas type phase transition.Comment: 44 pages, 16 Postscript figures, Fig14_nucl-ex.eps in colors, to be
published in Nucl.Phys.A (1999
On the reliability of negative heat capacity measurements
A global protocol for the thermostatistical analysis of hot nuclear sources
is discussed. Within our method of minimization of variances we show that the
abnormal kinetic energy fluctuation signal recently reported in different
experimental data (M.D'Agostino et al.-Phys. Lett. B 473 (2000) 219, N. Le
Neindre et al.- contr. to the XXXVIII Bormio Winter Meeting on Nucl. Phys.
(2001) 404) is a genuine signal of a first order phase transition in a finite
system.Comment: 15 Postscript figures, submitted to NUCL. Phys. A on 24-apr-200
SNPs inFAM13AandIL2RBgenes are associated with FeNO in adult subjects with asthma
Nitric oxide has different roles in asthma as both an endogenous modulator of airway function and a pro-inflammatory mediator. Fractional exhaled nitric oxide (FeNO) is a reliable, quantitative, non-invasive, simple, and safe biomarker for assessing airways inflammation in asthma. Previous genome-wide and genetic association studies have shown that different genes and single nucleotide polymorphisms (SNPs) are linked to FeNO. We aimed at identifying SNPs in candidate genes or gene regions that are associated with FeNO in asthma. We evaluated 264 asthma cases (median age 42.8 years, female 47.7%) who had been identified in the general adult population within the Gene Environment Interactions in Respiratory Diseases survey in Verona (Italy; 2008-2010). Two hundred and twenty-one tag-SNPs, which are representative of 50 candidate genes, were genotyped by a custom GoldenGate Genotyping Assay. A two-step association analysis was performed without assuming ana priorigenetic model: step 1) a machine learning technique [Gradient Boosting Machine (GBM)] was used to select the 15 SNPs with the highest variable importance measure; step 2) the GBM-selected SNPs were jointly tested in a linear regression model with natural log-transformed FeNO as the normally distributed outcome and with age, sex, and the SNPs as covariates. We replicated our results within an independent sample of 296 patients from the European Community Respiratory Health Survey III. We found that SNP rs987314 in family with sequence similarity 13 member A (FAM13A) and SNP rs3218258 in interleukin 2 receptor subunit beta (IL2RB) gene regions are significantly associated with FeNO in adult subjects with asthma. These genes are involved in different mechanisms that affect smooth muscle constriction and endothelial barrier function responses (FAM13A), or in immune response processes (IL2RB). Our findings contribute to the current knowledge on FeNO in asthma by identifying two novel SNPs associated with this biomarker of airways inflammation
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