In this paper, we address the problem of no-reference quality assessment for digital pictures corrupted with blur. We start with the generation of a large real image database containing pictures ...taken by human users in a variety of situations, and the conduction of subjective tests to generate the ground truth associated to those images. Based upon this ground truth, we select a number of high quality pictures and artificially degrade them with different intensities of simulated blur (gaussian and linear motion), totalling 6000 simulated blur images. We extensively evaluate the performance of state-of-the-art strategies for no-reference blur quantification in different blurring scenarios, and propose a paradigm for blur evaluation in which an effective method is pursued by combining several metrics and low-level image features. We test this paradigm by designing a no-reference quality assessment algorithm for blurred images which combines different metrics in a classifier based upon a neural network structure. Experimental results show that this leads to an improved performance that better reflects the images' ground truth. Finally, based upon the real image database, we show that the proposed method also outperforms other algorithms and metrics in realistic blur scenarios.
We present the first scientific results from the luminous red galaxy (LRG) sample of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) combined with the high-redshift galaxies of the ...previous BOSS sample. We measure the small- and intermediate-scale clustering from a sample of more than 97,000 galaxies in the redshift range . We interpret these measurements in the framework of the Halo Occupation Distribution. The bias of this sample of LRGs is 2.30 0.03, with a satellite fraction of 13% 3% and a mean halo mass of . These results are consistent with expectations, demonstrating that these LRGs will be reliable tracers of large-scale structure at . The galaxy bias implies a scatter of luminosity at fixed halo mass, , of 0.19 dex. Using the clustering of massive galaxies from BOSS CMASS, BOSS LOWZ, and SDSS, we find that is consistent with observations over the full redshift range that these samples cover. The addition of eBOSS to previous surveys allows the investigation of the evolution of massive galaxies over the past ∼7 Gyr.
Polymer hydrogels have been suggested as dressing materials for the treatment of cutaneous wounds and tissue revitalization. In this work, we report the development of a hydrogel composed of natural ...polymers (sodium alginate and gelatin) and silver nanoparticles (AgNPs) with recognized antimicrobial activity for healing cutaneous lesions. For the development of the hydrogel, different ratios of sodium alginate and gelatin have been tested, while different concentrations of AgNO
precursor (1.0, 2.0, and 4.0 mM) were assayed for the production of AgNPs. The obtained AgNPs exhibited a characteristic peak between 430-450 nm in the ultraviolet-visible (UV-Vis) spectrum suggesting a spheroidal form, which was confirmed by Transmission Electron Microscopy (TEM). Fourier Transform Infra-red (FT-IR) analysis suggested the formation of strong intermolecular interactions as hydrogen bonds and electrostatic attractions between polymers, showing bands at 2920, 2852, 1500, and 1640 cm
. Significant bactericidal activity was observed for the hydrogel, with a Minimum Inhibitory Concentration (MIC) of 0.50 µg/mL against
and 53.0 µg/mL against
s. AgNPs were shown to be non-cytotoxic against fibroblast cells. The in vivo studies in female Wister rats confirmed the capacity of the AgNP-loaded hydrogels to reduce the wound size compared to uncoated injuries promoting histological changes in the healing tissue over the time course of wound healing, as in earlier development and maturation of granulation tissue. The developed hydrogel with AgNPs has healing potential for clinical applications.
Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among ...the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GC–MS (gas chromatography–mass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25mgmL−1 for thyme, 5.0mgmL−1 for basil and marjoram, and 10mgmL−1 for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.
Weak-lensing measurements of the averaged shear profiles of galaxy clusters binned by some proxy for cluster mass are commonly converted to cluster mass estimates under the assumption that these ...cluster stacks have spherical symmetry. In this paper, we test whether this assumption holds for optically selected clusters binned by estimated optical richness. Using mock catalogues created from N-body simulations populated realistically with galaxies, we ran a suite of optical cluster finders and estimated their optical richness. We binned galaxy clusters by true cluster mass and estimated optical richness and measure the ellipticity of these stacks. We find that the processes of optical cluster selection and richness estimation are biased, leading to stacked structures that are elongated along the line of sight. We show that weak-lensing alone cannot measure the size of this orientation bias. Weak-lensing masses of stacked optically selected clusters are overestimated by up to 3–6 per cent when clusters can be uniquely associated with haloes. This effect is large enough to lead to significant biases in the cosmological parameters derived from large surveys like the Dark Energy Survey, if not calibrated via simulations or fitted simultaneously. This bias probably also contributes to the observed discrepancy between the observed and predicted Sunyaev–Zel'dovich signal of optically selected clusters.
Purpose
To determine the risk factors related to adnexal involvement in endometrial cancer (EC) and its implications for ovarian preservation in young women.
Methods
We analyzed a series of 802 ...patients who were treated at AC Camargo Cancer Center from July 1991 to July 2017. Patients who had peritoneal or systemic dissemination (stage IV) were excluded. Chi square and Fisher’s exact tests were used to analyze the correlations between categories and clinicopathological variables. Multivariate analysis was performed by logistic regression.
Results
Forty-nine (6.2%) patients had adnexal involvement—43 (5.4%) ovarian and 24 (2.9%) tubal. After excluding the 14 (28%) cases with suspicious findings, 788 subjects were analyzed and adnexal involvement found in 35 (4.4%) cases. Adnexal involvement was statistically related to non-endometrioid histologies (12.6% vs. 3.1%;
p
< 0.001), lymph node metastasis (17% vs. 2.6%;
p
< 0.001), histological grade 3 tumors (9.4% vs. 2.1%;
p
< 0.001), presence of LVSI (14.2% vs. 2.4%;
p
< 0.001), and deep myometrial invasion (≥ 50%) (10.8% vs. 3.5%;
p
< 0.001). Although age younger than 45 years had higher risk of adnexal involvement, it was not statistically significant (8.9% vs. 4.2%;
p
= 0.13). Seven (14.2%) patients with adnexal involvement were aged < 45 years, 3 of whom (42.8%) had suspicious adnexal masses that were detected before surgery. Notably, all patients aged < 45 years and with adnexal involvement had at least 1 risk factor, such as presence of LVSI, grade 3 disease, node metastasis, or deep myometrial invasion. No patient with clinically normal ovaries and aged under 45 years, with endometrioid grades 1 and 2, superficial myometrial invasion, or node negativity had adnexal involvement.
Conclusions
Ovarian preservation may be considered for patients younger than 45 years old with low-risk EC (grades 1 and 2 tumors, absence of LVSI, and myometrial invasion < 50%).
We report the discovery of 13 confirmed two-image quasar lenses from a systematic search for gravitationally lensed quasars in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). We adopted ...a methodology similar to that used in the SDSS Quasar Lens Search (SQLS). In addition to the confirmed lenses, we report 11 quasar pairs with small angular separations ( ≲ 2 arcsec) confirmed from our spectroscopy, which are either projected pairs, physical binaries, or possibly quasar lens systems whose lens galaxies have not yet been detected. The newly discovered quasar lens system, SDSS J1452+4224 at z
s ≈ 4.8 is one of the highest redshift multiply imaged quasars found to date. Furthermore, we have over 50 good lens candidates yet to be followed up. Owing to the heterogeneous selection of BOSS quasars, the lens sample presented here does not have a well-defined selection function.
ABSTRACT
We derive the metallicity (traced by the O/H abundance) of the narrow-line region (NLR) of 108 Seyfert galaxies as well as radial metallicity gradients along their galaxy discs and of these ...of a matched control sample of no active galaxies. In view of that, observational data from the SDSS-IV MaNGA survey and strong emission-line calibrations taken from the literature were considered. The metallicity obtained for the NLRs was compared to the value derived from the extrapolation of the radial oxygen abundance gradient, obtained from H ii region estimates along the galaxy disc, to the central part of the host galaxies. We find that, for most of the objects ($\sim 80\, {{\ \rm per\ cent}}$), the NLR metallicity is lower than the extrapolated value, with the average difference ($\langle$D$\rangle$) between these estimates ranging from 0.16 to 0.30 dex. We suggest that $\langle$D$\rangle$ is due to the accretion of metal-poor gas to the AGN that feeds the nuclear supermassive black hole (SMBH), which is drawn from a reservoir molecular and/or neutral hydrogen around the SMBH. Additionally, we look for correlations between D and the electron density (Ne), O iiiλ5007, and H α luminosities, extinction coefficient (AV) of the NLRs, as well as the stellar mass (M*) of the host galaxies. Evidence of an inverse correlation between the D and the parameters Ne, M*, and Av was found.
Rationale
Annona species are of interest for the isolation of bioactive molecules; however, studies of Annona jahnii Saff. are limited. The exploration of bioactive metabolites of endophytes isolated ...from this species is unprecedented and allows the preservation of the host plant, in addition to enabling the discovery of compounds with promising biological activities.
Methods
Ethyl acetate extracts from the cultured media of five fungi were obtained. The antioxidant capacity of the extracts was measured using the 1,1‐diphenyl‐2‐picrylhydrazyl free radical method. Antimicrobial activity was determined using the microdilution method in broth in 96‐well plates. The exploration of the metabolic profile of the extracts and dereplication of the compounds were performed using ultra‐high‐performance liquid chromatography/electrospray ionization/tandem mass spectrometry (UHPLC/ESI‐MS/MS) combined with analysis using molecular networking (MN).
Results
A total of 1818 MS features were detected in the five selected extracts, of which 39 compounds were putatively identified. The secondary metabolites with the highest abundance were alkaloids, naphthopyrons, and cytochalasins. Other secondary metabolites include fumonisins, coumarin, and a meroterpenoid. Most of these compounds are related to specific biological properties such as antioxidant, anti‐inflammatory, antimicrobial, antiviral, and antitumor activities. Extracts F398 and F403 showed inhibitory activity of the four pathogens tested. Extracts F475 and F506 did not inhibit the growth of Staphylococcus aureus, and F407 did not inhibit the growth of Escherichia coli in addition to having potent antioxidant activity, with IC50 values of 10 μg/mL or less.
Conclusions
The use of UHPLC/ESI‐MS/MS data combined with MN proved useful in the dereplication of bioactive molecules of complex extracts that are still unexplored. These initial investigations should significantly assist in further research and increase the efficiency and speed in the discovery of new sources of secondary metabolites and new natural products.
Covert Attacks in Cyber-Physical Control Systems Oliveira de Sa, Alan; Rust Da Costa Carmo, Luiz F.; Machado, Raphael C. S.
IEEE transactions on industrial informatics,
08/2017, Letnik:
13, Številka:
4
Journal Article
Odprti dostop
The advantages of using communication networks to interconnect controllers and physical plants motivate the increasing number of networked control systems in industrial and critical infrastructure ...facilities. However, this integration also exposes such control systems to new threats, typical of the cyber domain. In this context, studies have been conducted, aiming to explore vulnerabilities and propose security solutions for cyber-physical systems. In this paper, a covert attack for service degradation is proposed, which is planned based on the intelligence gathered by another attack, herein proposed, referred as system identification attack. The simulation results demonstrate that the joint operation of the two attacks is capable to affect, in a covert and accurate way, the physical behavior of a system.
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