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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.

Non invasive fibrosis biomarkers reduce but not substitute the need for liver biopsy

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World Journal of Gastroenterology 2006年第23期12卷 3682-3694页

作者： Giada Sebastiani Alfredo Alberti Department of Clinical and Experimental Medicine University of PadovaPadovaItaly

Chronic liver diseases are very common worldwide, particularly those linked to viral hepatitis and to alcoholic and non-alcoholic fatty liver. Their natural history is variable and long-term evolution differs in individual patients. Optimised clinical management of compensated chronic liver diseases requires precise definition of the stage of liver fibrosis, the main determinant of prognosis and of most therapeutic decisions. Liver biopsy is the gold standard for assessment of hepatic fibrosis. However, it is invasive with possible complications, costly and prone to sampling errors. Many non-invasive markers of liver fibrosis have been recently proposed and assessed in the clinical setting as surrogates of liver biopsy. Direct markers are based on biochemical parameters directly linked to fibrogenesis while indirect markers use simple or more sophisticated parameters that correlate with liver fibrosis stages. Non-invasive markers of liver fibrosis have been tested in different forms of chronic liver disease and showed variable diagnostic performance, but accuracy rarely was above 75%-80%. Better results were obtained when markers were combined. On this line, we have recently proposed a set of algorithms that combine sequentially indirect non-invasive markers of liver fibrosis, reaching 90%-95% diagnostic accuracy with significant reduction in the need for liver biopsy. Based on available evidence, it can be anticipated that non-invasive markers of liver fibrosis and their combined use will soon become a most useful tool in the clinical management of many forms of chronic liver disease. However, their implementation is expected to reduce, but not to completely eliminate, the need for liver biopsy.

关键词： Chronic liver diseases Hepatic fibrosis Liverbiopsy Non invasive fibrosis markers

Three-dimensional in vitro models of neuromuscular tissue

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Neural Regeneration Research 2022年第4期17卷 759-766页

作者： Paolo Raffa Maria Easler Anna Urciuolo Institute of Pediatric Research IRP PadovaItaly Molecular Medicine Department University of PadovaPadovaItaly

Skeletal muscle is a dynamic tissue in which homeostasis and function are guaranteed by a very defined three-dimensional organization of myofibers in respect to other nonmuscular components,including the extracellular matrix and the nervous *** particular,communication between myofibers and the nervous system is essential for the overall correct development and function of the skeletal muscle.A wide range of chronic,acute and genetic-based human pathologies that lead to the alteration of muscle function are associated with modified preservation of the fine interaction between motor neurons and myofibers at the neuromuscular *** advancements in the development of in vitro models for human skeletal muscle have shown that three-dimensionality and integration of multiple cell types are both key parameters required to unveil pathophysiological relevant ***,we describe recent achievement reached in skeletal muscle modeling which used biomaterials for the generation of three-dimensional constructs of myotubes integrated with motor neurons.

关键词： 3D organization bioengineering biomaterials motor neurons neuromuscular junction skeletal muscle models

Water oxidation electrocatalysis with iron oxide nanoparticles prepared via laser ablation

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Journal of Energy Chemistry 2016年第2期25卷 244-248页

作者： Erica Pizzolato Stefano Scaramuzza Francesco Carraro Alessia Sartori Stefano Agnoli Vincenzo Amendola Marcella Bonchio Andrea Sartorel Department of Chemical Sciences University of Padova Institute on Membrane Technology unit of Padova

Iron oxide nanoparticles（FeOx NPs, 5–30 nm size） prepared via laser ablation in liquid were supported onto Indium Tin Oxide conductive glass slides by magnetophoretic deposition（MD） technique. The resulting Fe O x@ITO electrodes are characterized by a low amount of iron coverage of 16–50 nmol/cm^2,and show electrocatalytic activity towards water oxidation in neutral phosphate buffer pH 7 with 0.58 V overpotential and quantitative Faradaic efficiency towards oxygen production. XPS analysis on the oxygen region of the FeOx films reveals a substantial hydration of the surface after catalysis, recognized as a crucial step to access reactivity.

关键词： Water oxidation Electrocatalysis Iron oxide Laser ablation Nanoparticles

Non-destructive OAM measurement via light-matter interaction

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Light(Science & Applications) 2022年第3期11卷 10-12页

作者： Gianluca Ruffato Department of Physics and Astronomy‘G.Galilei’ University of PadovaPadovaItaly Quantum Technologies Research Center(QTech) University of PadovaPadovaItaly

The detection of orbital angular momentum usually relies on optical techniques,which modify the original beam to convert the information carried on its phase into a specific intensity distribution in ***,the exploitation of high-intensity beams can result destructive for standard optical elements and setups.A recent publication suggests a solution to overcome all those limitations,by probing highly-intense vortex pulses with a structured reference beam in a strong-field photoionization process.

关键词： beam overcome interaction

Control of wind-wave power on morphological shape of salt marsh margins

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Water Science and Engineering 2020年第1期13卷 45-56页

作者： Alvise Finotello Marco Marani Luca Carniello Mattia Pivato Marcella Roner Laura Tommasini Andrea D'alpaos Department of Geosciences University of PadovaPadova 35131Italy Department of Environmental Sciences Informatics and StatisticsUniversity of Venice Ca'FoscariVenice 30172Italy Center for Lagoon Hydrodynamics and Morphodynamics University of PadovaPadova 35131Italy Department of Civil Environmental and Architectural EngineeringUniversity of PadovaPadova 35131Italy

Salt marshes are among the most common morphological features found in tidal landscapes and provide ecosystem services of primary ecological and economic ***,the continued rise in relative sea level and increasing anthropogenic pressures threaten the sustainability of these *** alarmingly high rates of salt marsh loss observed worldwide,mainly dictated by the lateral erosion of their margins,call for new insights into the mutual feedbacks among physical,biological,and morphological processes that take place at the critical interface between salt marshes and the adjoining tidal *** combined field measurements,remote sensing data,and numerical modeling to investigate the interplays between wind waves and the morphology,ecology,and planform evolution of salt marsh margins in the Venice Lagoon of *** results confirm the existence of a positive linear relationship between incoming wave power density and rates of salt marsh lateral *** addition,we show that lateral erosion significantly decreases when halophytic vegetation colonizes the marsh margins,and that different erosion rates in vegetated margins are associated with different *** marsh cliffs and smooth shorelines are expected along rapidly eroding margins,whereas erosion rates are reduced in gently sloped,irregular edges facing shallow tidal flats that are typically exposed to low wind-energy *** highlighting the relationships between the dynamics and functional forms of salt marsh margins,our results represent a critical step to address issues related to conservation and restoration of salt marsh ecosystems,especially in the face of changing environmental forcings.

关键词： Salt marshes Wind waves Lateral erosion Morphodynamics Vegetation

Toward the use of smartphones for mobile mapping

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Geo-Spatial Information Science 2016年第3期19卷 210-221页

作者： Andrea Masiero Francesca Fissore Francesco Pirotti Alberto Guarnieri Antonio Vettore Interdepartmental Research Center of Geomatics(CIRGEO) University of PadovaPadovaItaly

This paper considers the use of a low cost mobile device in order to develop a mobile mapping system(MMS),which exploits only sensors embedded in the *** goal is to make this MMS usable and reliable even in difficult environments(*** conditions,when also WiFi connection might not work).For this aim,a navigation system able to deal with the unavailability of the GNSS(***)is proposed *** is achieved by a pedestrian dead reckoning approach,i.e.a specific particle filter has been designed to enable good position estimations by a small number of particles(e.g.100).This specific characteristic enables its real time use on the standard mobile ***,3D reconstruction of the scene can be achieved by processing multiple images acquired with the standard camera embedded in the *** most of the vision-based 3D reconstruction systems are recently proposed in the literature,this work considers the use of structure from motion to estimate the geometrical structure of the *** detail level of the reconstructed scene is clearly related to the number of images processed by the reconstruction ***,the execution of a 3D reconstruction algorithm on a mobile device imposes several restrictions due to the limited amount of available energy and computing *** consideration motivates the search for new methods to obtain similar results with less computational *** paper proposes a novel method for feature matching,which allows increasing the number of correctly matched features between two images according to our simulations and can make the matching process more robust.

关键词： Mobile mapping positioning feature matching smartphone

Oxidative damage in the progression of chronic liver disease to hepatocellular carcinoma:An intricate pathway

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World Journal of Gastroenterology 2014年第12期20卷 3078-3086页

作者： Romilda Cardin Marika Piciocchi Marina Bortolami Andromachi Kotsafti Luisa Barzon Enrico Lavezzo Alessandro Sinigaglia Kryssia Isabel Rodriguez-Castro Massimo Rugge Fabio Farinati Department of Surgery Oncology and GastroenterologyUniversity of Padova Department of Molecular Medicine University of Padova Department of Medicine University of Padova

The histo-pathologic and molecular mechanisms leading to initiation and progression of hepatocellular carcinoma (HCC) are still ill-defined; however, there is increasing evidence that the gradual accumulation of mutations, genetic and epigenetic changes which occur in preneoplastic hepatocytes results in the development of dysplastic foci, nodules, and finally, overt HCC. As well as many other neoplasias, liver cancer is considered an “inflammatory cancer”, arising from a context of inflammation, and characterized by inflammation-related mechanisms that favor tumor cell survival, proliferation, and invasion. Molecular mechanisms that link inflammation and neoplasia have been widely investigated, and it has been well established that inflammatory cells recruited at these sites with ongoing inflammatory activity release chemokines that enhance the production of reactive oxygen species. The latter, in turn, probably have a major pathogenic role in the continuum starting from hepatitis followed by chronic inflammation, and ultimately leading to cancer. The relationship amongst chronic liver injury, free radical production, and development of HCC is explored in the present review, particularly in the light of the complex network that involves oxidative DNA damage, cytokine synthesis, telomere dysfunction, and microRNA regulation.

关键词： Reactive oxygen species Viral hepatitis Hepatocellular carcinoma Telomere dysfunction Cytokines mitochondria Antioxidant mechanisms MicroRNA and circulating free DNA

Grain refinement of gravity die cast secondary AlSi7Cu3Mg alloys for automotive cylinder heads

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Transactions of Nonferrous Metals Society of China 2016年第5期26卷 1211-1221页

作者： Giordano CAMICIA Giulio TIMELLI Department of Management and Engineering University of Padova

The effects of AITi5B1 grain refinement and cooling rate on the microstructure and mechanical properties of a secondary AlSi7Cu3Mg alloy were reported. Metallographic and image analysis techniques have been used to quantitatively examine the macrostructural and microstructural changes occurring with the addition of grain-refining agent at different cooling rates by using a step casting die. The results indicate that the addition of AlTi5B1 produces a fine and uniform grain structure throughout the casting and this effect is more pronounced in the slowly solidified regions. Increasing the cooling rate, lower amount of grain refiner is necessary to produce a uniform grain size throughout the casting. On the other hand, the initial contents of Ti and B, present as impurity elements in the supplied secondary alloy, are not sufficient to produce an effective grain refinement. The results from the step casting geometry were applied to investigate a gasoline 16V cylinder head, which was produced by gravity semi-permanent mould technology. The grain refinement improves the plastic behaviour of the alloy and increases the reliability of the casting, as evidenced by the Weibull statistics.

关键词： aluminium alloy grain refinement step casting cylinder head cooling rate microstructure mechanical properties

Use of oleaginous plants in phytotreatment of grey water and yellow water from source separation of sewage

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Journal of Environmental Sciences 2017年第5期29卷 274-282页

作者： Maria Cristina Lavagnolo Mario Malagoli Luca Alibardi Francesco Garbo Alberto Pivato Raffaello Cossu Department of Industrial Engineering University of Padova via Lungargine Rovetta 8 35127 Padova Italy DAFNAE University of Padova viale dell'Universita 16 35020 Legnaro Italy

Efficient and economic reuse of waste is one of the pillars of modern environmental engineering. In the field of domestic sewage management,source separation of yellow（urine）,brown（faecal matter）and grey waters aims to recover the organic substances concentrated in brown water,the nutrients（nitrogen and phosphorous）in the urine and to ensure an easier treatment and recycling of grey waters. With the objective of emphasizing the potential of recovery of resources from sewage management,a lab-scale research study was carried out at the university of padova.in order to evaluate the performances of oleaginous plants（suitable for biodiesel production）in the phytotreatment of source separated yellow and grey waters. The plant species used were Brassica napus（rapeseed）,Glycine max（soybean）and Helianthus annuus（sunflower）. Phytotreatment tests were carried out using 20 L pots. Different testing runs were performed at an increasing nitrogen concentration in the feedstock. The results proved that oleaginous species can conveniently be used for the phytotreatment of grey and yellow waters from source separation of domestic sewage,displaying high removal efficiencies of nutrients and organic substances（nitrogen 〉 80%; phosphorous 〉 90%; COD nearly 90%）. No inhibition was registered in the growth of plants irrigated with different mixtures of yellow and grey waters,where the characteristics of the two streams were reciprocally and beneficially integrated.

关键词： Phytotreatment Sewage Source separation Decentralization Grey water Urine Energy crops