141 research outputs found
Exploitation of tannic acid as additive for the adhesion enhancement of UV-curable bio-based coating
The interest in environmentally friendly coatings is rising to substitute for the oil-derived materials in the coating industry. In the present study, natural tannic acid (TA) is investigated as an additive to an epoxidized soybean oil-based (ESO) coating. TA solutions in propylene carbonate at two different concentrations were prepared and added to an ESO matrix with different weight ratios. The UV-curing process of the coatings was deeply assessed through real-time Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning photo Calorimetry (photo-DCS). A significant increase in high epoxy group conversion, around 90 %, was achieved thanks to the activated monomer mechanism, which involves the TA polyphenols. This mechanism accelerated the photocrosslinking process, but reduced the coatings' crosslinking density, as demonstrated by the dynamic thermal mechanical analysis. The hardness of coatings containing the TA additive decreased, while the hydrophobicity of the surface coatings remained unchanged after the TA incorporation. Lastly, the adhesion of the UV-cured coating was evaluated on low-carbon steel substrates. An outstanding enhancement in adhesion property was provided by the TA additive, whose phenols not only participate in the photocrosslinking reaction but also coordinate iron on the steel surface. Moreover, the influence of two different steel surface pre-treatments, the pickling and plasma processes, on the coatings' adhesion strength was studied
Testing generalized scalar-tensor theories of gravity with clusters of galaxies
We test the generalized scalar-tensor theory in static systems, namely galaxy
clusters. The Degenerate higher-order scalar-tensor (DHOST) theory modifies the
Newtonian potential through effective Newtonian constant and parameter
in the small scale, which modifies the hydrostatic equilibrium. We utilize the
well-compiled X-COP catalog consisting of 12 clusters with Intra Cluster Medium
(ICM) pressure profile by Sunyaev-Zeldovich effect data and temperature profile
by X-ray data for each cluster. We perform a fully Bayesian analysis modeling
Navarro-Frenk-White (NFW) for the mass profile, and the simplified Vikhlinin
model for the electron density. Carefully selecting suitable clusters to
present our results, we find a mild to moderate, i.e,
significance for a deviation from the standard scenario in 4 of the clusters.
However, in terms of Bayesian evidence, we find either equivalent or mild
preference for GR. We estimate a joint constraint of
using 8 clusters, for a modification from a CDM scenario. This limit
is in very good agreement with theoretical ones and an order of magnitude more
stringent than the previous constraint obtained using clusters. We also quote a
more conservative limit of . Finally, we comment on
the tentative redshift dependence (), finding a mild preference () for the same.Comment: Comments are Welcom
On the shear estimation bias induced by the spatial variation of colour across galaxy profiles
The spatial variation of the colour of a galaxy may introduce a bias in the
measurement of its shape if the PSF profile depends on wavelength. We study how
this bias depends on the properties of the PSF and the galaxies themselves. The
bias depends on the scales used to estimate the shape, which may be used to
optimise methods to reduce the bias. Here we develop a general approach to
quantify the bias. Although applicable to any weak lensing survey, we focus on
the implications for the ESA Euclid mission.
Based on our study of synthetic galaxies we find that the bias is a few times
10^-3 for a typical galaxy observed by Euclid. Consequently, it cannot be
neglected and needs to be accounted for. We demonstrate how one can do so using
spatially resolved observations of galaxies in two filters. We show that HST
observations in the F606W and F814W filters allow us to model and reduce the
bias by an order of magnitude, sufficient to meet Euclid's scientific
requirements. The precision of the correction is ultimately determined by the
number of galaxies for which spatially-resolved observations in at least two
filters are available. We use results from the Millennium Simulation to
demonstrate that archival HST data will be sufficient for the tomographic
cosmic shear analysis with the Euclid dataset.Comment: MNRAS submitted, 18 pages, 13 Figure
Peripheral Edema: Differential Diagnosis
Peripheral edemas can be generated by multiple causes, local and/or systemic. The difficulties in recognizing the exact nature of the edema and the cause that originates it often lead to erroneous considerations that determine an inappropriate therapeutic approach. In this chapter the various causes that generate peripheral edema are analyzed (systemic: cardiac diastolic dysfunction, kidney failure, liver failure, myxedema, from drugs, and idiopathic; and local: venous and/or lymphatic transport insufficiency). They are also described, according to the diagnosis made and the clinical and instrumental criteria to attain a correct and early diagnosis and to proceed to the most appropriate therapeutic measures (drugs, surgery, physical rehabilitative by means of manual and mechanical techniques) in individual cases
Scrapie infectivity is quickly cleared in tissues of orally-infected farmed fish
BACKGROUND: Scrapie and bovine spongiform encephalopathy (BSE) belongs to the group of animal transmissible spongiform encephalopathy (TSE). BSE epidemic in the UK and elsewhere in Europe has been linked to the use of bovine meat and bone meals (MBM) in the feeding of cattle. There is concern that pigs, poultry and fish bred for human consumption and fed with infected MBM would eventually develop BSE or carry residual infectivity without disease. Although there has been no evidence of infection in these species, experimental data on the susceptibility to the BSE agent of farm animals other than sheep and cow are limited only to pigs and domestic chicken. In the framework of a EU-granted project we have challenged two species of fish largely used in human food consumption, rainbow trout (Oncorhynchus mykiss) and turbot (Scophthalmus maximus), with a mouse-adapted TSE strain (scrapie 139A), to assess the risk related to oral consumption of TSE contaminated food. In trout, we also checked the "in vitro" ability of the pathological isoform of the mouse prion protein (PrP(Sc)) to cross the intestinal epithelium when added to the mucosal side of everted intestine. RESULTS: Fish challenged with a large amount of scrapie mouse brain homogenate by either oral or parenteral routes, showed the ability to clear the majority of infectivity load. None of the fish tissues taken at different time points after oral or parenteral inoculation was able to provoke scrapie disease after intracerebral inoculation in recipient mice. However, a few recipient mice were positive for PrP(Sc )and spongiform lesions in the brain. We also showed a specific binding of PrP(Sc )to the mucosal side of fish intestine in the absence of an active uptake of the prion protein through the intestinal wall. CONCLUSION: These results indicate that scrapie 139A, and possibly BSE, is quickly removed from fish tissues despite evidence of a prion like protein in fish and of a specific binding of PrP(Sc )to the mucosal side of fish intestine
Biochemical and neuropathological findings in a Creutzfeldt-Jakob Disease patient with the rare Val180Ile-129Val haplotype in the prion protein gene
Genetic Creutzfeldt-Jakob disease (gCJD) associated with the V180I mutation in the prion protein (PrP) gene (PRNP) in phase with residue 129M is the most frequent cause of gCJD in East Asia, whereas it is quite uncommon in Caucasians. We report on a gCJD patient with the rare V180I-129V haplotype, showing an unusually long duration of the disease and a characteristic pathological PrP (PrPSc) glycotype. Family members carrying the mutation were fully asymptomatic, as commonly observed with this mutation. Neuropathological examination showed a lesion pattern corresponding to that commonly reported in Japanese V180I cases with vacuolization and gliosis of the cerebral cortexes, olfactory areas, hippocampus and amygdala. PrP was deposited with a punctate, synaptic-like pattern in the cerebral cortex, amygdala and olfactory tract. Western blot analyses of proteinase-K-resistant PrP showed the characteristic two-banding pattern of V180I gCJD, composed of mono- and un-glycosylated isoforms. In line with reports on other V180I cases in the literature, Real-Time Quaking Induced Conversion (RT-QuIC) analyses did not demonstrate the presence of seeding activity in the cerebrospinal fluid and olfactory mucosa, suggesting that this haplotype also may result in a reduced seeding efficiency of the pathological PrP. Further studies are required to understand the origin, penetrance, disease phenotype and transmissibility of 180I-129V haplotype in Caucasians
A novel pathway to detect muscle-invasive bladder cancer based on integrated clinical features and VI-RADS score on MRI: results of a prospective multicenter study
Purpose To determine the clinical, pathological, and radiological features, including the Vesical Imaging-Reporting and Data System (VI-RADS) score, independently correlating with muscle-invasive bladder cancer (BCa), in a multicentric national setting. Method and Materials Patients with BCa suspicion were offered magnetic resonance imaging (MRI) before trans-urethral resection of bladder tumor (TURBT). According to VI-RADS, a cutoff of >= 3 or >= 4 was assumed to define muscle-invasive bladder cancer (MIBC). Trans-urethral resection of the tumor (TURBT) and/or cystectomy reports were compared with preoperative VI-RADS scores to assess accuracy of MRI for discriminating between non-muscle-invasive versus MIBC. Performance was assessed by ROC curve analysis. Two univariable and multivariable logistic regression models were implemented including clinical, pathological, radiological data, and VI-RADS categories to determine the variables with an independent effect on MIBC. Results A final cohort of 139 patients was enrolled (median age 70 [IQR: 64, 76.5]). MRI showed sensitivity, specificity, PPV, NPV, and accuracy for MIBC diagnosis ranging from 83-93%, 80-92%, 67-81%, 93-96%, and 84-89% for the more experienced readers. The area under the curve (AUC) was 0.95 (0.91-0.99). In the multivariable logistic regression model, the VI-RADS score, using both a cutoff of 3 and 4 (P < .0001), hematuria (P = .007), tumor size (P = .013), and concomitant hydronephrosis (P = .027) were the variables correlating with a bladder cancer staged as >= T2. The inter-reader agreement was substantial (k = 0.814). Conclusions VI-RADS assessment scoring proved to be an independent predictor of muscle-invasiveness, which might implicate a shift toward a more aggressive selection approach of patients' at high risk of MIBC, according to a novel proposed predictive pathway
Efficient Transmission and Characterization of Creutzfeldt–Jakob Disease Strains in Bank Voles
Transmission of prions between species is limited by the “species barrier,” which hampers a full characterization of human prion strains in the mouse model. We report that the efficiency of primary transmission of prions from Creutzfeldt–Jakob disease patients to a wild rodent species, the bank vole (Clethrionomys glareolus), is comparable to that reported in transgenic mice carrying human prion protein, in spite of a low prion protein–sequence homology between man and vole. Voles infected with sporadic and genetic Creutzfeldt–Jakob disease isolates show strain-specific patterns of spongiform degeneration and pathological prion protein–deposition, and accumulate protease-resistant prion protein with biochemical properties similar to the human counterpart. Adaptation of genetic Creutzfeldt–Jakob disease isolates to voles shows little or no evidence of a transmission barrier, in contrast to the striking barriers observed during transmission of mouse, hamster, and sheep prions to voles. Our results imply that in voles there is no clear relationship between the degree of homology of the prion protein of the donor and recipient species and susceptibility, consistent with the view that the prion strain gives a major contribution to the species barrier. The vole is therefore a valuable model to study human prion diversity and, being susceptible to a range of animal prions, represents a unique tool for comparing isolates from different species
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