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Dynamic Recrystallization Behavior of Q370qE Bridge Steel

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 330-340页

作者： Caiyi Liu Shicheng Liang Yan Peng Jianliang Sun Carlo Mapelli silvia barella Andrea Gruttadauria Marco Belf Ludovica Rovatti National Engineering Research Center for Equipment and Technology of Cold Roll Strip Rolling Yanshan UniversityQinhuangdao 066004China Department of Mechanical Engineering Politecnico di Milano20156 MilanItaly

Bridge steel has been widely used in recent years for its excellent performance. Understanding the high-temperature Dynamic Recrystallization (DRX) behavior of high-performance bridge steel plays an important role in guiding the thermomechanical processing process. In the present study, the hot deformation behavior of Q370qE bridge steel was investigated by hot compression tests conducted on a Gleeble 3800-GTC thermal-mechanical physical simulation system at temperatures ranging from 900 ℃ to 1100 ℃ and strain rates ranging from 0.01 s^(−1) to 10 s^(−1). The obtained results were used to plot the true stress-strain and work-hardening rate curves of the experimental steel, with the latter curves used to determine the critical strains for the initiation of DRX. The Zener-Hollomon equation was subsequently applied to establish the correspondence between temperature and strain rate during the high-temperature plastic deformation of bridge steel. In terms of the DRX volume fraction solution, a new method for establishing DRX volume fraction was proposed based on two theoretical models. The good weathering and corrosion resistance of bridge steel lead to difculties in microstructure etching. To solve this, the MTEX technology was used to further develop EBSD data to characterize the original microstructure of Q370qE bridge steel. This paper lays the theoretical foundation for studying the DRX behavior of Q370qE bridge steel.

关键词： Dynamic recrystallization Materials characterization Hot deformation DRX volume fraction model

Solidification microstructure of centrifugally cast Inconel 625

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China Foundry 2017年第4期14卷 304-312页

作者： silvia barella Andrea Gruttadauria Carlo Mapelli Davide Mombelli Paolo Taiana Matteo Bosatra Alberto Morini Dipartimento di Meccanica Politecnico di Milanovia La Masa 120156 MilanoItaly Fondinox via Marconi 42/4826010 Sergnano(CR)Italy

Centrifugal casting is a foundry process allowing the production of near net-shaped axially symmetrical components. The present study focuses on the microstructural characterization of centrifugally cast alloys featuring different chemical compositions for the construction of spheres applied in valves made of alloy IN625 for operation at high pressure. Control of the solidification microstructure is needed to assure the reliability of the castings. Actually, a Ni-base superalloy such as this one should have an outstanding combination of mechanical properties, high temperature stability and corrosion resistance. Alloys such as IN625 are characterised by a large amount of alloying elements and a wide solidification range, so they can be affected by micro-porosity defects, related to the shrinkage difference between the matrix and the secondary reinforcing phases(Nb-rich carbides and Laves phase). In this study, the microstructure characterization was performed as a function of the applied heat treatments and it was coupled with a calorimetric analysis in order to understand the mechanism ruling the formation of micro-porosities that can assure alloy soundness. The obtained results show that the presence of micro-porosities is governed by morphology and by the size of the secondary phases, and the presence of the observed secondary phases is detrimental to corrosion resistance.

关键词： alloy IN625 centrifugal casting solidification defects Nb carbides Laves phases micro-porosity corrosion

The complex role of protocadherin-19 in brain function:a focus on the oxytocin system

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Neural Regeneration Research 2025年第11期20卷 3211-3212页

作者： Sara Mazzoleni Marta Busnelli silvia Bassani CNR Institute of Neuroscience Vedano al LambroItaly NeuroMi Milan Center for Neuroscience MilanItaly

Mutations in the protocadherin-19(PCDH19)gene(Xq22.1)cause the X-linked syndrome known as developmental and epileptic encephalopathy 9(DEE9,OMIM#300088)(Dibbens et al.,2008).DEE9 is characterized by early-onset clustering epilepsy associated with intellectual disability ranging from mild to profound,autism spectrum disorder,and other neuropsychiatric features including schizophrenia,anxiety,attentiondeficit/hyperactivity,and obsessive or aggressive *** seizures may become less frequent in adolescence,psychiatric comorbidities persist and often worsen with age(Dibbens et al.,2008;Kolc et al.,2020).

关键词： epilepsy function system

How Plants Cope with Cadmium: Staking All on Metabolism and Gene Expression

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Journal of Integrative Plant Biology 2008年第10期50卷 1268-1280页

作者： Giovanni DalCorso silvia Farinati silvia Maistri Antonella Furini Dipartimento Scientifico e Tecnologico Universita` degli Studi di Verona Strada Le Grazie 15 37134 Verona Italy

Environmental pollution is one of the major problems for human health. Toxic heavy metals are normally present as soil constituents or can also be spread out in the environment by human activity and agricultural techniques. Soil contamination by heavy metals as cadmium, highlights two main aspects： on one side they interfere with the life cycle of plants and therefore reduce crop yields, and on the other hand, once adsorbed and accumulated into the plant tissues, they enter the food chain poisoning animals and humans. Considering this point of view, understanding the mechanism by which plants handle heavy metal exposure, in particular cadmium stress, is a primary goal of plant-biotechnology research or plant breeders whose aim is to create plants that are able to recover high amounts of heavy metals, which can be used for phytoremediation, or identify crop varieties that do not accumulate toxic metal in grains or fruits. In this review we focus on the main symptoms of cadmium toxicity both on root apparatus and shoots. We elucidate the mechanisms that plants activate to prevent absorption or to detoxify toxic metal ions, such as synthesis of phytochelatins, metallothioneins and enzymes involved in stress response. Finally we consider new plant-biotechnology applications that can be applied for phytoremediation.

关键词： cadmium heavy metals metallothioneins phytochelatins phytoremediation transporters.

Decoding Phthorimaea operculella(Lepidoptera: Gelechiidae) in the new age of change

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Journal of Integrative Agriculture 2020年第2期19卷 316-324页

作者： silvia I.RONDON Hermiston Agricultural Research and Extension Center Crop and Soil ScienceOregon State University

Arthropods and pathogens constantly challenge potato Solanum tuberosum *** of climate variation have increased the possibility of changes in pests’biological and ecological patterns by increasing or reducing overwintering length,changes in population growth rates,number of generations,crop-pest relationship,and therefore affecting their *** operculella Zeller(Lepidoptera:Gelechiidae)is one of the main pests affecting potatoes *** oviposit single or multiple eggs in leaves,stems,and tubers,while the larvae in immature stage mine leaves or burrows into tubers turning them *** control methods are effective in controlling ***,but many factors determine the success of the control *** review provides key highlights of current information available that could be used as a resource to fight this pest.

关键词： climate insects moth potato pest management Solanaceae pest control IPM tubermoth potato tuber moth

Genotoxicity biomarkers in aquatic bioindicators

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Current Zoology 2014年第2期60卷 273-284页

作者： Claudia BOLOGNESI silvia CIRILLO Environmental Carcinogenesis Unit IRCCS Azienda Ospedaliera Universitaria San Martino- IST Istituto Nazionale Ricerca sulCancro L.go Rosanna Benzi 10 Genova Italy

Pollution of the aquatic environment is an ever-growing problem, as waters are the ultimate sink for the large number of xenobiotics from multiple sources. DNA damaging agents have a significant ecological relevance since they are implicated in many pathological processes and exert effects beyond that of individual being active through following generations. A large number of methods have been applied to evaluate genotoxic damage in different aquatic species. Comet assay, as method for de- tecting DNA alterations, and micronucleus test, as an index of chromosomal damage are the most widely applied and validated methods in field studies. These methods were applied in different vertebrate and invertebrate aquatic species, but only mollusk and fish species have been employed in routine biomonitoring programs. Mussels, due to their widely geographical distribution and the suitability for caging represent the bioindicator of choice in field studies. Mytilus species is the most used marine mussel. The use of fish is limited to specific geographic areas. The present review mainly focuses on the application of comet assay and micronucleus test in mussels. A number of biomonitoring studies in mussels, using comet assay or micronucleus test, revealed exposure to different classes of genotoxic compounds with a good discrimination power. The different evidence from the two as- says, reflects different biological mechanisms for the two genetic endpoints, DNA damage and chromosomal damage, suggesting their combined application in the field. Different endogenous and exogenous factors have been shown to modulate the genotoxic responses in mussels, acting as confounding factors in environmental monitoring. The use of standardized protocol for caging, sampling and genotoxity evaluation is critical in biomonitoring studies. The use of a multimarker approach coupling genotoxicity biomarkers with physiological and biochemical factors allows to have a complete picture of the environmenta

关键词： Aquatic animals Genotoxicity Bioindicator Biomarker Micronucleus test Comet assay Bivalve Mussel

PCDH19 interplay with GABA(A)receptors:a window to DEE9 pathogenetic mechanisms

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Neural Regeneration Research 2022年第4期17卷 803-805页

作者： Sara Mazzoleni silvia Bassani Institute of Neuroscience CNRMilanItaly Department of Medical Biotechnology and Translational Medicine University of MilanSegrate(MI)Italy NeuroMI Milan Center for Neuroscience University of Milano-BicoccaMilanItaly

Developmental and epileptic encephalopathy 9(DEE9):The gene PCDH19(Xq22.1),which encodes the calcium-dependent cell adhesion protein protocadherin-19(PCDH19),is nowadays considered as one of the most important genes in monogenic epilepsy(Depienne and LeGuern,2012).Mutations in PCDH19 are responsible for DEE9(OMIM#300088),a severe neurodevelopmental disorder characterized by early-onset clustering epilepsy,various degrees of cognitive impairment and neuro psychiatric comorbidities,like autism spectrum disorder(ASD)and behavioural ***9 patients start suffering from seizures around the age of 10 months until adolescence,when seizures tend to reduce or even disappear,while the psychiatric symptoms persist(Depienne and LeGuern,2012;Kolc et al.,2018).

关键词： H19 PCD epilepsy

Sperm priming response to perceived mating opportunities is reduced in male guppies with high baseline sperm production

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Current Zoology 2018年第2期64卷 205-211页

作者： silvia CATTELAN Andrea PILASTRO Department of Biology University of Padova Padova 35131 Italy

Producing sperm is costly and males have been selected to strategically adjust their sperm produc- tion and/or expenditure according to the fitness return associated with a specific mating. For exam- ple, males respond to fluctuations in the mating opportunities by adjusting the number of ＂ready＂ sperm. This phenomenon is known as ＂sperm priming＂ and is interpreted as a strategy to econo- mize the investment in sperm. The cost and benefits of the sperm priming response, however, are expected to depend on a male＇s baseline sperm production （BSP） in the absence of females, because of the different risk of sperm depletion and the nonlinearly increasing costs of sperm pro- duction. We tested this prediction in 2 replicated lines of male guppies Poecilia reticulata that were artificially selected for high and low BSP. BSP has a large genetic variance and a high sire heritabil- ity in guppies, and males respond to the perceived mating opportunities by increasing the number of ＂ready＂ sperm. We investigated whether males with a different BSP differed in their sperm pri- ming response. We found that when the perceived mating opportunities increased, males from low-sperm lines had a stronger sperm priming response than those from high-sperm lines. This result suggests that adaptive plasticity in sperm priming has the potential to evolve in response to different levels of BSP. The comparison between guppy populations with different levels of sperm production would allow to test whether the pattern reported here is also observed at the interpopulation level.

关键词： artificial selection mate availability Poecilia reticulata sperm investment sperm priming sperm production.

Alanine and aspartate aminotransferase and glutamine-cycling pathway:Their roles in pathogenesis of metabolic syndrome

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World Journal of Gastroenterology 2012年第29期18卷 3775-3781页

作者： silvia Sookoian Carlos J Pirola Department of Clinical and Molecular Hepatology Institute of Medical Research A Lanari-IDIMUniversity of Buenos Aires-National Council of Scientific and Technological Research(CONICET)Ciudad Autónoma de Buenos Aires 1427Argentina Department of Molecular Genetics and Biology of Complex Diseases Institute of Medical Research A Lanari-IDIMUniversity of Buenos Aires-National Council of Scientific and Technological Research(CONICET)Ciudad Autónoma de Buenos Aires 1427Argentina

Although new research technologies are constantly used to look either for genes or biomarkers in the prediction of metabolic syndrome(MS),the pathogenesis and pathophysiology of this complex disease remains a major ***,Cheng et al recently investigated possible pathways underlying MS by high-throughput metabolite profiling in two large and well characterized community-based *** authors explored by liquid chromatography and mass spectrometry the plasma concentrations of 45 distinct metabolites and examined their relation to cardiometabolic risk,and observed that metabolic risk factors such as obesity,insulin resistance(IR),high blood pressure,and dyslipidemia were associated with several metabolites,including branched-chain amino acids,other hydrophobic amino acids,tryptophan breakdown products,and nucleotide *** addition,the authors found a significant association of IR traits with glutamine,glutamate and the glutamineto-glutamate *** data provide new insight into the pathogenesis of MS-associated phenotypes and introduce a crucial role of glutamine-cycling pathway as prominently involved in the development of metabolic *** consider that the hypothesis about the role of abnormal glutamate metabolism in the pathogenesis of the MS is certainly challenging and suggests the critical role of the liver in the global metabolic modulation as glutamate metabolism is linked with aminotransferase *** discuss here the critical role of the "liver metabolism" in the pathogenesis of the MS and IR,and postulate that before fatty liver develops,abnormal levels of liver enzymes,such as alanine and aspartate aminotransferases might reflect high levels of hepatic transamination of amino acids in the liver.

关键词： Alanine Aspartate Glutamine Glutamate 2-oxoglutarate Glycolysis Pyruvate