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41.
This article is focused on the comparison of the reliability of the results obtained by image analysis (newly proposed evaluation method) with well-known methods of evaluation of long-term corrosion resistance of glass fibers in an alkaline environment (pH > 12). The developed method is based on the analysis of scanning electron microscopy images (diameter and structures on the fiber surface). An experiment (52 weeks) was performed to evaluate two types of glass fibers: anticorrosive glass fibers (ARGFs) and E-glass fibers (EGFs). Three media were used to treat the fibers (23 ± 2 °C): H2O, Ca(OH)2, and K2SiO3. The ARGFs’ tensile strength did not reduce; a decrease by 68% was observed for EGFs in H2O. Tensile strength decreased by 32% and 85–95% in K2SiO3; by 50% and 64% in Ca(OH)2 for the ARGF and EGF, respectively. Statistical analysis was performed to validate the reliability and plausibility of the developed method. ARGFs and EGFs did not show any relationship between the fiber diameter and weight in H2O; however, the linear trends may predict this relationship in Ca(OH)2 and K2SiO3. For the ARGF and EGF, the cubic trend was suitable for predicting the change in fiber weight and diameter over time in Ca(OH)2 and K2SiO3. 相似文献
42.
Background: High hydrostatic pressure (HHP) processing is a non-thermal method proposed as an alternative to Holder pasteurization (HoP) for the sterilization of human breast milk (BM). HHP preserves numerous milk bioactive factors that are degraded by HoP, but no data are available for milk apelin and glucagon-like peptide 1 (GLP-1), two hormones implicated in the control of glucose metabolism directly and via the gut–brain axis. This study aims to determine the effects of HoP and HHP processing on apelin and GLP-1 concentrations in BM and to test the effect of oral treatments with HoP- and HHP-BM on intestinal contractions and glucose metabolism in adult mice. Methods: Mice were treated by daily oral gavages with HoP- or HHP-BM during one week before intestinal contractions, and glucose tolerance was assessed. mRNA expression of enteric neuronal enzymes known to control intestinal contraction was measured. Results: HoP-BM displayed a reduced concentration of apelin and GLP-1, whereas HHP processing preserved these hormones close to their initial levels in raw milk. Chronic HHP-BM administration to mice increased ileal mRNA nNos expression level leading to a decrease in gut contraction associated with improved glucose tolerance. Conclusion: In comparison to HoP, HPP processing of BM preserves both apelin and GLP-1 and improves glucose tolerance by acting on gut contractions. This study reinforces previous findings demonstrating that HHP processing provides BM with a higher biological value than BM treated by HoP. 相似文献
43.
Cdric Rossi Marie Tosolini Pauline Gravelle Sarah Pericart Salim Kanoun Solene Evrard Julia Gilhodes Don-Marc Franchini Nadia Amara Charlotte Syrykh Pierre Bories Lucie Oberic Loïc Ysebaert Laurent Martin Selim Ramla Philippine Robert Claire Tabouret-Viaud Ren-Olivier Casasnovas Jean-Jacques Fourni Christine Bezombes Camille Laurent 《Haematologica》2022,107(1):221
44.
Brice Mastrovito Chlo Naimi Leslie Kouam Xavier Naudot Lucie Fournier Guillaume Spaccaferri Jean-Christophe Plantier Anaïs Soares Fabienne De Oliveira Marie Gueudin Vronique Jacomo Cline Leroy Alice Moisan Mlanie Martel 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(6)
Three confirmed infections with the SARS-CoV-2 B.1.640 variant under monitoring were reported in Normandy, north-western France in late November 2021. Investigations led to the identification of two events linked to the same cluster. A total of 75 confirmed and probable B.1.640 cases were reported. All had completed the primary vaccination series. Sixty-two cases were older than 65 years. Fifty-six cases had symptoms and four were hospitalised. This investigation provides preliminary results concerning a variant with limited information currently available. 相似文献
45.
Garel Juliette Blondiaux Eléonore Della Valle Valeria Guilbaud Lucie Khachab Farah Jouannic Jean-Marie Ducou le Pointe Hubert Garel Catherine 《Pediatric radiology》2020,50(4):575-582
A wide range of genitourinary pathologies can be diagnosed in utero, from a simple vesicoureteral reflux to a more complex disorder of sexual differentiation. The prognosis and neonatal management of these conditions differ significantly. Evaluation of the fetal perineal anatomy is paramount to making the right diagnosis. The aim of this pictorial essay is to show sonographers how to acquire a perineal midsagittal view in a male fetus, and to demonstrate how this specific view allows assessment of the urethra and penis, to differentiate various genitourinary pathologies.
相似文献46.
47.
Several strategies have been developed to fight viral infections, not only in humans but also in animals and plants. Some of them are based on the development of efficient vaccines, to target the virus by developed antibodies, others focus on finding antiviral compounds with activities that inhibit selected virus replication steps. Currently, there is an increasing number of antiviral drugs on the market; however, some have unpleasant side effects, are toxic to cells, or the viruses quickly develop resistance to them. As the current situation shows, the combination of multiple antiviral strategies or the combination of the use of various compounds within one strategy is very important. The most desirable are combinations of drugs that inhibit different steps in the virus life cycle. This is an important issue especially for RNA viruses, which replicate their genomes using error-prone RNA polymerases and rapidly develop mutants resistant to applied antiviral compounds. Here, we focus on compounds targeting viral structural capsid proteins, thereby inhibiting virus assembly or disassembly, virus binding to cellular receptors, or acting by inhibiting other virus replication mechanisms. This review is an update of existing papers on a similar topic, by focusing on the most recent advances in the rapidly evolving research of compounds targeting capsid proteins of RNA viruses. 相似文献
48.
49.
Mirko Mattia Lucie Biehler-Gomez Emanuela Sguazza Paolo Maria Galimberti Folco Vaglienti Daniele Gibelli Pasquale Poppa Giulia Caccia Marco Caccianiga Stefano Vanin Laura Manthey Richard L. Jantz Domenico Di Candia Emanuela Maderna Giuliana Albini Sachin Pawaskar Franklin Damann Anna Maria Fedeli Elena Belgiovine Daniele Capuzzo Fabrizio Slavazzi Cristina Cattaneo 《Medical history》2022,66(1):24
The Ospedale Maggiore, known as Ca’ Granda, was founded in 1456 by will of Francesco Sforza, Duke of Milan, and was considered for almost five centuries a model for Milanese, Italian and even European healthcare. Attracting patients from all over Europe, the Ca’ Granda distinguished itself for the introduction of new treatments and innovative health reforms. In the burial ground of the hospital still lie the bodies of the deceased patients, who came from the poorest strata of the population. The study of their remains aims to give back a general identity and a story to each of these persons as well as reconstruct a fraction of the sixteenth century population of Milano as concerns lifestyle and disease and examine practises and therapy of this exceptional hospital. It is estimated that about two million commingled bones and articulated skeletons rest in the crypt, together with other types of findings (e.g., ceramic, coins, clothing). These remains are the object of a large project involving various disciplines ranging from humanities to hard sciences. The aim of this paper is to bring this historical gem to the attention of scholars and provide a glimpse of what its contents have already revealed. 相似文献
50.
Kristina Kverkov Lucie Marhounov Alexandra Polonyiov Martin Kocourek Yicheng Zhang Seweryn Olkowicz Barbora Strakov Zuzana Pavelkov Roman Vodi
ka Daniel Frynta Pavel Nmec 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(11)
Reconstructing the evolution of brain information-processing capacity is paramount for understanding the rise of complex cognition. Comparative studies of brain evolution typically use brain size as a proxy. However, to get a less biased picture of the evolutionary paths leading to high cognitive power, we need to compare brains not by mass but by numbers of neurons, which are their basic computational units. This study reconstructs the evolution of brains across amniotes by directly analyzing neuron numbers by using the largest dataset of its kind and including essential data on reptiles. We show that reptiles have not only small brains relative to body size but also low neuronal densities, resulting in average neuron numbers over 20 times lower than those in birds and mammals of similar body size. Amniote brain evolution is characterized by the following four major shifts in neuron–brain scaling. The most dramatic increases in brain neurons occurred independently with the appearance of birds and mammals, resulting in convergent neuron scaling in the two endotherm lineages. The other two major increases in the number of neurons happened in core land birds and anthropoid primates, which are two groups known for their cognitive prowess. Interestingly, relative brain size is associated with relative neuronal cell density in reptiles, birds, and primates but not in other mammals. This has important implications for studies using relative brain size as a proxy when looking for evolutionary drivers of animal cognition.The evolution of cognitive capacity or “intelligence” and its underlying neural substrate has been of long-standing interest to biologists. Great strides have been made in understanding the evolution of brain size in vertebrates, with studies analyzing data on thousands of species (1–3). Since larger animals have larger brains but are not necessarily smarter, most studies of cognitive evolution use relative brain size (corrected for body size), which is thought to reflect extra neurons beyond those needed for controlling the body (4). We now have a good idea where major changes in brain–body scaling happened within birds (2) and mammals (3), and it is also clear that both mammals and birds have relatively larger brains than nonavian sauropsids (hereafter referred to as reptiles), although this has been rarely formally quantified because data on reptilian brain sizes are scarce (5).However, we still lack a clear picture of the evolution of actual brain processing capacity. This is because the same increase in relative brain size can be reached by different evolutionary paths, not always involving actual brain enlargement, and might often result from selection on body size (3). Moreover, similarly sized brains of distantly related species can harbor substantially different numbers of neurons overall and in major brain parts (6, 7). These two caveats invalidate the very idea that we can estimate extra neurons and glean information about cognitive capacity from absolute or relative brain size alone.This capacity is better determined by the number of neurons in the brain or specific brain parts (although their relative importance is still debated), their connections, interneuronal distance, and axonal conduction velocity (8, 9). Unlike brain size, though, these measures are not readily available for a sufficient number of species to be of practical use. Nevertheless, thanks to methodological advances (10), neuronal scaling rules (the allometric relationship between brain mass and neuron numbers) have now been determined for eight high-level mammalian clades (6, 11–13) as well as for a limited sampling of birds (14, 15).To get the big picture of amniote brain evolution, we have to include data on nonavian reptiles. The deepest split in amniote evolution occurred between the synapsid lineage, leading to mammals, and the sauropsid lineage, including reptiles and birds. We cannot tell if similarities between birds and mammals are due to shared ancestry or convergent evolution without considering reptiles. Yet, the dearth of quantitative data on reptile brains is striking—brain mass is available for 183 species (5, 16), compared to thousands for birds and mammals, and neuron numbers are known for a mere 4 reptile species (17–19).Taken together, to understand the evolution of brain processing capacity in amniotes, we need to include nonavian reptiles, consider changes in both brain–body and neuron–brain scaling, and examine the allocation of neurons to different brain parts. In this study, we provide these much needed data and reconstruct the big picture of brain evolution in amniotes in terms of neuron numbers. 相似文献