Erosion wear of glass fibre reinforced vinyl ester

This study evaluates the slurry-erosion wear of glass fibre reinforced vinyl ester composites (VE-FRP) using a high speed slurry-pot type wear tester. The wear rates of VE-FRP were compared using different abrasives, namely quartz, chromite, copper ore, zinc concentrate, and tailings. Furthermore, the effect of abrasive particle size and slurry concentration on the VE-FRP wear was studied. The erosion wear results of VE-FRP were compared to natural rubber (NR) and bromobutyl rubber (BIIR) as well as to few common thermoplastics, such as polypropylene (PP) and polyvinyl chloride (PVC). Moreover, the failure characteristics of VE-FRP were analyzed. The results demonstrated that coarse quartz produced the largest wear rates on VE-FRP samples, while the zinc concentrate showed the lowest wear. Minor changes in the abrasive particle size had no effect on the wear results, only when the particle size was markedly raised, the wear started to increase. When comparing the wear rates of different materials, it was concluded that with all abrasive types, tested rubbers and thermoplastics had lower wear rates than VE-FRP

Multifrequency Observations of the Gamma-Ray Blazar 3C 279 in Low-State during Integral AO-1

We report first results of a multifrequency campaign from radio to hard X-ray energies of the prominent gamma-ray blazar 3C 279 during the first year of the INTEGRAL mission. The variable blazar was found at a low activity level, but was detected by all participating instruments. Subsequently a multifrequency spectrum could be compiled. The individual measurements as well as the compiled multifrequency spectrum are presented. In addition, this 2003 broadband spectrum is compared to one measured in 1999 during a high activity period of 3C 279.Comment: 4 pages including 6 figures, to appear in: 'Proc. of the 5th INTEGRAL Workshop', ESA SP-552, in pres

Effect of Donor Simvastatin Treatment on Gene Expression Profiles in Human Cardiac Allografts during Ischemia-Reperfusion Injury

Purpose Numerous studies have shown that statin therapy initiated early after heart transplantation has beneficial effects on the development of cardiac allograft vasculopathy. Recently, we were able to show in a randomized clinical trial that simvastatin treatment of brain-dead donors conditions the heart transplant to withstand ischemia-reperfusion injury and to reduce the need for rejection treatments early after transplantation. In this study, we analyzed myocardial gene expression profiles in cardiac allografts after donor simvastatin treatment. Methods 84 heart transplant donors received 80 mg of simvastatin via nasogastric tube (n=42), or no treatment (n=42) in a prospective, double-blinded randomized controlled trial. Transmural Tru-Cut biopsies were taken from the apex of left ventricle of the donor heart immediately before reperfusion and 1 hour after reperfusion. 20 heart biopsies from donors without treatment and 20 heart biopsies from donors with simvastatin treatment will be analyzed with RNA sequencing. Results The preliminary analysis of RNA sequencing data from myocardial biopsies revealed altogether 137 significantly differentially expressed genes in all pairwise comparisons. The overall biological functions of these genes were related to gene ontology terms such as response to toxic substance, leukocyte migration, neutrophil mediated immunity, response to lipopolysaccharide, and response to oxidative stress. At the KEGG pathway level, our results indicated alterations in IL-17, TNF, MAPK and the AGE-RAGE signaling pathways. Conclusion We have shown in previous studies that donor simvastatin treatment induces protective effects against IRI in heart transplant recipients. In this study, we were able to detect significantly differentially expressed genes related to effects of simvastatin treatment. In order to single out genes that show beneficial effects of simvastatin treatment, further analysis will be conducted by exploring gene expression changes in specific biological functional categories, such as interleukin signaling and neutrophil degranulation. The complete analysis will be presented at the ISHLT 2019 congress.Peer reviewe

Identification of Individual Glandular Regions Using LCWT and Machine Learning Techniques

A new approach for the segmentation of gland units in histological images is proposed with the aim of contributing to the improvement of the prostate cancer diagnosis. Clustering methods on several colour spaces are applied to each sample in order to generate a binary mask of the different tissue components. From the mask of lumen candidates, the Locally Constrained Watershed Transform (LCWT) is applied as a novel gland segmentation technique never before used in this type of images. 500 random gland candidates, both benign and pathological, are selected to evaluate the LCWT technique providing results of Dice coefficient of 0.85. Several shape and textural descriptors in combination with contextual features and a fractal analysis are applied, in a novel way, on different colour spaces achieving a total of 297 features to discern between artefacts and true glands. The most relevant features are then selected by an exhaustive statistical analysis in terms of independence between variables and dependence with the class. 3.200 artefacts, 3.195 benign glands and 3.000 pathological glands are obtained, from a data set of 1468 images at 10x magnification. A careful strategy of data partition is implemented to robustly address the classification problem between artefacts and glands. Both linear and non-linear approaches are considered using machine learning techniques based on Support Vector Machines (SVM) and feedforward neural networks achieving values of sensitivity, specificity and accuracy of 0.92, 0.97 and 0.95, respectivelyThis work has been funded by the Ministry of Economy, Industry and Competitiveness under the SICAP project (DPI2016-77869-C2-1-R). The work of Adri´an Colomer has been supported by the Spanish FPI Grant BES-2014-067889. We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan Xp GPU used for this researchGarcía-Pardo, JG.; Colomer, A.; Naranjo Ornedo, V.; Peñaranda, F.; Sales, MÁ. (2018). Identification of Individual Glandular Regions Using LCWT and Machine Learning Techniques. En Intelligent Data Engineering and Automated Learning – IDEAL 2018. Springer. 642-650. https://doi.org/10.1007/978-3-030-03493-1_67S642650Gleason, D.F.: Histologic grading and clinical staging of prostatic carcinoma. In: Urologic Pathology (1977)Naik, S., Doyle, S., Feldman, M., Tomaszewski, J., Madabhushi, A.: Gland segmentation and computerized gleason grading of prostate histology by integrating low-, high-level and domain specific information. In: MIAAB Workshop, pp. 1–8 (2007)Nguyen, K., Sabata, B., Jain, A.K.: Prostate cancer grading: gland segmentation and structural features. Pattern Recogn. Lett. 33(7), 951–961 (2012)Kwak, J.T., Hewitt, S.M.: Multiview boosting digital pathology analysis of prostate cancer. Comput. Methods Programs Biomed. 142, 91–99 (2017)Ren, J., Sadimin, E., Foran, D.J., Qi, X.: Computer aided analysis of prostate histopathology images to support a refined gleason grading system. In: SPIE Medical Imaging, International Society for Optics and Photonics, p. 101331V (2017)Soille, P.: Morphological Image Analysis: Principles and Applications. Springer, Berlin (2013)Nguyen, K., Sarkar, A., Jain, A.K.: Structure and context in prostatic gland segmentation and classification. In: Ayache, N., Delingette, H., Golland, P., Mori, K. (eds.) MICCAI 2012. LNCS, vol. 7510, pp. 115–123. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-33415-3_15Beare, R.: A locally constrained watershed transform. IEEE Trans. Pattern Anal. Mach. Intell. 28(7), 1063–1074 (2006)Gertych, A., et al.: Machine learning approaches to analyze histological images of tissues from radical prostatectomies. Comput. Med. Imaging Graph. 46, 197–208 (2015)Ojala, T., Pietikainen, M., Maenpaa, T.: Multiresolution gray-scale and rotation invariant texture classification with local binary patterns. IEEE Trans. Pattern Anal. Mach. Intell. 24(7), 971–987 (2002)Guo, Z., Zhang, L., Zhang, D.: A completed modeling of local binary pattern operator for texture classification. IEEE Trans. Image Process. 19(6), 1657–1663 (2010)Huang, P., Lee, C.: Automatic classification for pathological prostate images based on fractal analysis. IEEE Trans. Med. Imaging 28(7), 1037–1050 (2009)Ruifrok, A.C., Johnston, D.A., et al.: Quantification of histochemical staining by color deconvolution. Anal. Quant. Cytol. Histol. 23(4), 291–299 (2001

Differences in cardiac geometry in relation to body size among neonates with abnormal prenatal growth and body size at birth

Objectives Both excessive and restricted fetal growth are associated with changes in cardiac geometry and function at birth. There are significant issues when indexing cardiac parameters for body size in the neonatal period. The aims of this study were to determine to what extent cardiac geometry is dependent on body size in term and preterm neonates with restricted or excessive fetal growth and how this is affected by adiposity. Methods This was a cross-sectional study of neonates born between 31 and 42 weeks of gestation, divided into three groups: (1) small-for-gestational age (SGA, birth weight > 2 SD below the mean); (2) large-for-gestational age (LGA, birth weight > 2 SD above the mean); and (3) appropriate-for-gestational-age controls (AGA, birth weight Results In total, 174 neonates were included, of which 39 were SGA, 45 were LGA and 90 were AGA. Body size was reflected in cardiac dimensions, with differences in cardiac dimensions disappearing between the SGA and AGA groups when indexed for body surface area (BSA) or thoracic circumference. The same was true for the differences in atrial and ventricular areas between the LGA and AGA groups. However, left ventricular inflow and outflow tract dimensions did not follow this trend as, when indexed for BSA, they were associated negatively with adiposity, resulting in diminished dimensions in LGA compared with AGA and SGA neonates. Adiposity was associated positively with left ventricular mass, right ventricular length and area and right atrial area. The SGA group showed increased right ventricular fractional area change, possibly reflecting differences in the systolic function of the right ventricle. We found evidence of altered diastolic function between the groups, with the mitral valve inflow E-to lateral E'-wave peak velocity ratio being increased in the LGA group and decreased in the SGA group. Conclusions Cardiac geometry is explained by body size in both term and preterm AGA and SGA infants. However, the nature of the relationship between body size and cardiac dimensions may be influenced by adiposity in LGA infants, leading to underestimation of left ventricular inflow and outflow tract dimensions when adjusted for BSA. Adjustments for thoracic circumference provide similar results to those for BSA. Copyright (C) 2020 ISUOG. Published by John Wiley & Sons Ltd.Peer reviewe

A study of 15N14N isotopic exchange over cobalt molybdenum nitrides

The 14N/15N isotopic exchange pathways over Co3Mo3N, a material of interest as an ammonia synthesis catalyst and for the development of nitrogen transfer reactions, have been investigated. Both the homomolecular and heterolytic exchange processes have been studied, and it has been shown that lattice nitrogen species are exchangeable. The exchange behavior was found to be a strong function of pretreatment with ca. 25% of lattice N atoms being exchanged after 40 min at 600 °C after N2 pretreatment at 700 °C compared to only 6% following similar Ar pretreatment. This observation, for which the potential contribution of adsorbed N species can be discounted, is significant in terms of the application of this material. In the case of the Co6Mo6N phase, regeneration to Co3Mo3N under 15N2 at 600 °C occurs concurrently with 14N15N formation. These observations demonstrate the reactivity of nitrogen in the Co–Mo–N system to be a strong function of pretreatment and worthy of further consideration

Diffraction and Total Cross-Section at the Tevatron and the LHC

At the Tevatron, the total p_bar-p cross-section has been measured by CDF at 546 GeV and 1.8 TeV, and by E710/E811 at 1.8 TeV. The two results at 1.8 TeV disagree by 2.6 standard deviations, introducing big uncertainties into extrapolations to higher energies. At the LHC, the TOTEM collaboration is preparing to resolve the ambiguity by measuring the total p-p cross-section with a precision of about 1 %. Like at the Tevatron experiments, the luminosity-independent method based on the Optical Theorem will be used. The Tevatron experiments have also performed a vast range of studies about soft and hard diffractive events, partly with antiproton tagging by Roman Pots, partly with rapidity gap tagging. At the LHC, the combined CMS/TOTEM experiments will carry out their diffractive programme with an unprecedented rapidity coverage and Roman Pot spectrometers on both sides of the interaction point. The physics menu comprises detailed studies of soft diffractive differential cross-sections, diffractive structure functions, rapidity gap survival and exclusive central production by Double Pomeron Exchange.Peer reviewe

Spatial structure of the 8200 cal yr BP event in northern Europe

International audienceA synthesis of well-dated high-resolution pollen records suggests a spatial structure in the 8200 cal yr BP event in northern Europe. The temperate, thermophilous tree taxa, especially Corylus, Ulmus, and Alnus, decline abruptly between 8300 and 8000 cal yr BP at most sites located south of 61° N, whereas there is no clear change in pollen values at the sites located in the North-European tree-line region. Pollen-based quantitative temperature reconstructions and several other, independent palaeoclimate proxies, such as lacustrine oxygen-isotope records, reflect the same pattern, with no detectable cooling in the sub-arctic region. The observed patterns challenges the general view of the wide-spread occurrence of the 8200 cal yr BP event in the North Atlantic region. An alternative explanation is that the cooling during the 8200 cal yr BP event took place mostly during the winter and spring, and the ecosystems in the south responded sensitively to the cooling during the onset of the growing season. In contrast, in the sub-arctic area, where the vegetation was still dormant and lakes ice-covered, the cold event is not reflected in pollen-based or lake-sediment-based records

The adaptive evolution of herbivory in freshwater systems

Herbivory is thought to be nutritionally inefficient relative to carnivory and omnivory, but herbivory evolved from carnivory in many terrestrial and aquatic lineages, suggesting that there are advantages of eating plants. Herbivory has been well-studied in both terrestrial and aquatic systems, and there is abundant information on feedbacks between herbivores and plants, coevolution of plant and herbivore defenses, mechanisms for mediating nutrient limitation, effects of nutrient limitation on herbivore life history, and, more recently, the origins of the herbivorous diet. Researchers have sufficiently defined the ecological context and evolutionary origins of the herbivorous diet, and these main areas of research have laid the groundwork for studying herbivory as an adaptation. However, we have yet to synthesize this information in a way that allows us to establish a framework of testable adaptive hypotheses. To understand the adaptive significance of this diet transition, we review the current literature and use evidence from these works as support for five hypotheses on the evolution of herbivory from carnivory: (1) intake efficiency—herbivores use part of their food source as habitat, thus minimizing the energy/time spent searching for food and avoiding predators; (2) suboptimal habitat—herbivory allows organisms to invade and establish populations in habitats that have high primary production but low abundance of animal prey; (3) heterotroph facilitation—herbivory is adaptive because herbivores consume microbes associated with producers; (4) lipid allocation—herbivory is adaptive because producers are rich in fatty acids, which fuel reproduction and storage; and (5) disease avoidance—herbivory minimizes animal-facilitated disease transmission. Due to the extensive literature, we have limited this review to discussing herbivory in freshwater systems. To our knowledge, no prior work has compiled a comprehensive list of conditions that favor an herbivorous diet in nature. With backgrounds in both theoretical and experimental ecology, the incorporation of these hypotheses to the current literature will provide information about diet evolution, where it is currently lacking