470 research outputs found
Media Bias and Polarization through the Lens of a Markov Switching Latent Space Network Model
News outlets are now more than ever incentivized to provide their audience
with slanted news, while the intrinsic homophilic nature of online social media
may exacerbate polarized opinions. Here, we propose a new dynamic latent space
model for time-varying online audience-duplication networks, which exploits
social media content to conduct inference on media bias and polarization of
news outlets. Our model contributes to the literature in several directions: 1)
we provide a model-embedded data-driven interpretation for the latent leaning
of news outlets in terms of media bias; 2) we endow our model with
Markov-switching dynamics to capture polarization regimes while maintaining a
parsimonious specification; 3) we contribute to the literature on the
statistical properties of latent space network models. The proposed model is
applied to a set of data on the online activity of national and local news
outlets from four European countries in the years 2015 and 2016. We find
evidence of a strong positive correlation between our media slant measure and a
well-grounded external source of media bias. In addition, we provide insight
into the polarization regimes across the four countries considered
Interacting Multiple Try Algorithms with Different Proposal Distributions
We propose a new class of interacting Markov chain Monte Carlo (MCMC)
algorithms designed for increasing the efficiency of a modified multiple-try
Metropolis (MTM) algorithm. The extension with respect to the existing MCMC
literature is twofold. The sampler proposed extends the basic MTM algorithm by
allowing different proposal distributions in the multiple-try generation step.
We exploit the structure of the MTM algorithm with different proposal
distributions to naturally introduce an interacting MTM mechanism (IMTM) that
expands the class of population Monte Carlo methods. We show the validity of
the algorithm and discuss the choice of the selection weights and of the
different proposals. We provide numerical studies which show that the new
algorithm can perform better than the basic MTM algorithm and that the
interaction mechanism allows the IMTM to efficiently explore the state space
2016 Central Italy Earthquakes: comparison between GPS signals and low-cost distributed MEMS arrays
Abstract. Modern seismic ground-motion sensors have reached an excellent
performance quality in terms of dynamic range and bandwidth resolution. The
weakest point in the recording of seismic events remains spatial sampling
and spatial resolution, due to the limited number of installed sensors. A
significant improvement in spatial resolution can be achieved by the use of
non-conventional motion sensors, such as low-cost distributed sensors arrays
or positioning systems, capable of increasing the density of classical
seismic recording networks. In this perspective, we adopted micro-electro
mechanical system (MEMS) sensors to integrate the use of standard
accelerometers for moderate-to-strong seismic events. In addition, we
analyse high-rate distributed positioning system data that also record soil
motion. In this paper, we present data from the 2016 Central Italy
earthquakes as recorded by a spatially dense prototype MEMS array installed
in the proximity of the epicentral area, and we compare the results to the
signal of local 1s GPS stations. We discuss advantages and limitations of
this joint approach, reaching the conclusion that such low-cost sensors and
the use of high rate GPS signal could be an effective choice for integrate
the spatial density of stations providing strong-motion parameters
Sensibilidade de isolados de Phytophthora infestans aos fungicidas metalaxyl e clorothalonil.
An update on treatment options for interstitial cystitis
Interstitial cystitis or bladder pain syndrome (IC/BPS) is a chronic pelvic pain syndrome related to the urinary bladder. The ideal treatment should match as much as possible with the pathophysiologic causes of the IC/BPS, but the scarcely available evidence limits this approach, with the majority of available treatments that are primarily targeted to the control of symptoms. The treatment strategies have traditionally focused on the bladder, which is considered the primary end-organ and source of pain. Nevertheless, the growing body of evidence suggests a multifaceted nature of the disease with systemic components. In general, guidelines recommend the personalized and progressive approach, that starts from the more conservative options and then advances toward more invasive and combined treatments. The behavioral changes represent the first and most conservative steps. They can be combined with oral medications or progressively with intravesical instillation of drugs, up to more invasive techniques in a combined way. Despite the multiple available options, the optimal treatment is not easy to be found. Only further investigation on the etiopathogenetic mechanisms, taking into account the differences among subgroups, and the interaction between central and peripherical factors may allow providing a real improvement in the treatment and management of these patients
Virgin and recycled polypropylene composites reinforced with sisal by-product
Foram estudadas as propriedades térmicas e mecânicas de compósitos de polipropileno, virgem e reciclado, reforçados com 30% em massa de fibras residuais de sisal, assim como o perfil de processamento e a morfologia da matriz polimérica. Para tanto, foram determinadas a resistência à tração, o módulo de Young, alongamento na ruptura, e energia de impacto. As amostras também foram caracterizadas por MEV, DMTA e TG. Para ambos os compósitos de polipropileno, virgem e reciclado, com a adição das fibras, o alongamento na ruptura mostrou uma queda significativa, enquanto que a resistência à tração não sofreu grandes variações. Houve um aumento significativo nos valores de tração na ruptura e de energia de impacto com a adição das fibras de sisal na matriz de polipropileno. As análises térmicas mostraram ligações secundárias, como as ligações polares, entre as fibras e a matriz, concordando com o comportamento mecânico dos compósitos. Constatou-se que a temperatura de transição vítrea não variou após a adição da fibra.The mechanical and thermal properties of virgin and recycled polypropylene composites reinforced with 30% by mass of residual sisal fibers were studied, in addition to an analysis of the extrusion process and morphology of the polymeric matrix. Tensile strength, Young's modulus, elongation at break, and impact energy were determined. The samples were also characterized by SEM, DMTA and TG analyses. Elongation at break of the composites presented a significant decrease, while the tensile strength was not affected significantly by addition of sisal fibers. A significant increase was observed in the tension of rupture and in the impact energy of the composite reinforced with sisal fiber. The thermal analyses indicated secondary interactions, such as polar interactions, between the fibers and the matrix, consistent with the mechanical behavior of the composites. The glass transition temperature has not changed after fiber addition.Universidade Federal de São Carlos - Departamento de Engenharia de MateriaisFinepCNP
Influencia de los tratamientos de revenidos intercríticos en la concentración de níquel correspondiente, a partículas de austenita residual en un acero con 9% Ni
Beyond Sentinel Lymph Node: Outcomes of Indocyanine Green-Guided Pelvic Lymphadenectomy in Endometrial and Cervical Cancer
Background: The aim of our study was to compare the number of lymph nodes removed during indocyanine green (ICG)-guided laparoscopic/robotic pelvic lymphadenectomy with standard systematic lymphadenectomy in endometrial cancer (EC) and cervical cancer (CC). Methods: This is a multicenter retrospective comparative study (Clinical Trial ID: NCT04246580; updated on 31 January 2023). Women affected by EC and CC who underwent laparoscopic/robotic systematic pelvic lymphadenectomy, with (cases) or without (controls) the use of ICG tracer injection within the uterine cervix, were included in the study. Results: The two groups were homogeneous for age (p = 0.08), Body Mass Index, International Federation of Gynaecology and Obstetrics (FIGO) stages (p = 0.41 for EC; p = 0.17 for CC), median estimated blood loss (p = 0.76), median operative time (p = 0.59), and perioperative complications (p = 0.66). Nevertheless, the number of lymph nodes retrieved during surgery was significantly higher (p = 0.005) in the ICG group (n = 18) compared with controls (n = 16). Conclusions: The accurate and precise dissection achieved with the use of the ICG-guided procedure was associated with a higher number of lymph nodes removed in the case of systematic pelvic lymphadenectomy for EC and CC
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