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Responses of Grafted Watermelon onto Cucurbita pepo Tiana F1 Hybrid to Boron Nutritional Disorders

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Horticultural Plant Journal 2019年第5期5卷 213-220页

作者： Shirani Bidabadi Siamak Sabbatini paolo Department of Horticulture College of AgricultureIsfahan University of TechnologyIsfahan84156-83111Iran Department of Horticulture Michigan State UniversityEast LansingMI48824USA

Sensitivity to boron stress in growing media during the early seedlings stage could severely inhibit watermelon growth and development. The aim of this study was to test if watermelon(Citrullus lanatus cv. Mahbubi) performance can be improved under different boron concentrations(0, 46.31 and 935.11 μmol·L-1 H3BO3) by grafting watermelon plants onto Cucurbita pepo Tiana F1 hybrid rootstock. Shoot dry weight of grafted watermelon was significantly higher than those of non-grafted plants under boron stress conditions(0 and 935.11 μmol·L-1). Boron concentration of the aerial organs of the grafted plants was higher than in the non-grafted ones when treated with 0 μmol·L-1 H3BO3. However, with the application of boron(935.11 μmol·L-1 H3BO3), the aerial organs of grafted plants accumulated lower boron than non-grafted ones. The Cucurbita pepo rootstock also improved the absorption of several other nutrients and leaf chlorophyll content and the Fv/Fmratio was also increased at high boron root concentration. Higher activities of several antioxidant enzymes such as catalase(CAT), superoxide dismutase(SOD) and peroxidase(POX) in grafted watermelons were associated with a significant reduction in H2O2 and malondialdehyde(MDA) generation when compared with those of non-grafted plants under boron stress conditions(0 and 935.11 μmol·L-1 H3BO3). Grafted plants reported improved growth, nutrient uptake and several other physiological parameters when compared to non-grafted watermelon plants under boron stress conditions.

关键词： Citrullus lanatus Cucurbita pepo lipid peroxidation oxidative stress rootstock

Quantum cellular automata and free quantum field theory

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Frontiers of physics 2017年第1期12卷 65-75页

作者： Giacomo Mauro D'Ariano paolo Perinottit QUIT Group Dipartimento di Fisica via Bassi 6 1-27100 Pavia Italy

In a series of recent papers [1-4] it has been shown how free quantum field theory can be derived without using mechanical primitives （including space-time, special relativity, quantization rules, etc.）, but only considering the easiest quantum algorithm encompassing a countable set of quantum systems whose network of interactions satisfies the simple principles of unitarity, homogeneity, locality, and isotropy. This has opened the route to extending the axiomatic information-theoretic derivation of the quantum theory of abstract systems [5, 6] to include quantum field theory. The inherent discrete nature of the informational axiomatization leads to an extension of quantum field theory to a quantum cellular automata theory, where the usual field theory is recovered in a regime where the discrete structure of the automata cannot be probed. A simple heuristic argument sets the scale of discreteness to the Planck scale, and the customary physical regime where discreteness is not visible is the relativistic one of small waveveetors. In this paper we provide a thorough derivation from principles that in the most general case the graph of the quantum cellular automaton is the Cayley graph of a finitely presented group, and showing how for the case corresponding to Euclidean emergent space （where the group resorts to an Abelian one） the automata leads to Weyl, Dirac and Maxwell field dynamics in the relativistic limit. We conclude with some perspectives towards the more general scenario of non-linear automata for interacting quantum field theory.

关键词： quantum automata quantum walks quantum fields axiomatics Planck scale

Thyroid hormones and thyroid hormone receptors: Effects of thyromimetics on reverse cholesterol transport

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World Journal of Gastroenterology 2010年第47期16卷 5958-5964页

作者： Matteo Pedrelli Camilla Pramfalk paolo Parini Division of Clinical Chemistry Department of Laboratory Medicine Molecular Nutrition Unit Biosciences and Nutrition Karolinska Institutet at Karolinska University Hospital Huddinge

Reverse cholesterol transport (RCT) is a complex process which transfers cholesterol from peripheral cells to the liver for subsequent elimination from the body via feces. Thyroid hormones (THs) affect growth, develop- ment, and metabolism in almost all tissues. THs exert their actions by binding to thyroid hormone receptors (TRs). There are two major subtypes of TRs, TRα and TRβ, and several isoforms (e.g. TRα1, TRα2, TRβ1, and TRβ2). Activation of TRα1 affects heart rate, whereas activation of TRβ1 has positive effects on lipid and lipoprotein metabolism. Consequently, particular interest has been focused on the development of thyromimetic compounds targeting TRβ1, not only because of their ability to lower plasma cholesterol but also due their ability to stimulate RCT, at least in pre-clinical models. In this review we focus on THs, TRs, and on the effects of TRβ1-modulating thyromimetics on RCT in various animal models and in humans.

关键词： Cardiovascular disease Cholesterol Lipoprotein metabolism Reverse cholesterol transport Thyroid hormones Thyroid hormone receptors

Microstructure and Thermal Conductivity of Al–Graphene Composites Fabricated by Powder Metallurgy and Hot Rolling Techniques

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Acta Metallurgica Sinica(English Letters) 2017年第7期30卷 675-687页

作者： Abdollah Saboori Matteo Pavese Claudio Badini paolo Fino Department of Applied Science and Technology Politecnico di Torino Corso Duca degli Abruzzi 24 10129 Turin Italy

The objective of this research is to improve the thermal conductivity and mechanical properties of Al/GNPs（graphene nanoplatelets） nanocomposites produced by classical powder metallurgy and hot rolling techniques. The microstructural evaluation confirmed the uniform dispersion of GNPs at low content and agglomeration at higher contents of GNPs. The structure of graphene was studied before and after the mixing and the Raman spectrum proofs that the wet mixing has a great potential to be used as a dispersion method. There was no significant peak corresponding to the Al_4C_3 formation in both the differential scanning calorimetry curves and X-ray diffraction patterns. The microstructural observation in both fabrication techniques showed grain refinement as a function of the GNPs content. Moreover, the introduction of the GNPs not only improved the Vickers hardness of the composites but also decreased their density. The thermal conductivity investigations showed that in both the press-sintered and hot-rolled samples, although the thermal conductivity of composites was improved at low GNPs contents, it was negatively affected at high GNPs contents.

关键词： Aluminum Graphene Thermal conductivity Powder metallurgy Microstructure

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

Visual communication in social play of a hierarchical carnivore species:the case of wild spotted hyenas

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Current Zoology 2022年第4期68卷 411-421页

作者： Andrea paolo Nolfo Grazia Casetta Elisabetta Palagi Department of Biology Unit of EthologyUniversity of PisaVia A.Volta 6Pisa56126Italy Natural History Museum University of PisaVia Roma 79CalciPisa56011Italy

Communication relies on signals that can be produced via different sensory modalities to modify receivers’*** social interactions,the possibility to perceive subtle visual cues enhances the use of facial expressions to exchange *** of the most appropriate fields to explore the specific design features of visual signals is play ***,we explored the production and potential role of Relaxed Open Mouth(ROM)and Head Bobbing(HB)in regulating play fighting of wild spotted hyenas Crocuta crocuta,a highly hierarchical carnivore *** accordance with the assumptions of the signal optimization theory,wild hyenas produced ROM and HB almost exclusively when the sender was in direct visual contact with the receiver thus suggesting that senders were attentive to the playmates’*** to HB,the sequential analysis revealed that ROM often anticipated offensive patterns such as play biting thus supporting the hypothesis that ROM,but not HB,is a metacomunicative ***,when the offensive patterns were biased toward one of the 2 players,the session was punctuated by a higher number of *** findings support the general hypothesis that these 2 visual signals can play different roles in the management of play fighting in this carnivore *** complementary use of ROM and HB would suggest that spotted hyenas are highly competent and fast in processing facial displays of different nature to correctly“read others’intentions”and respond with appropriate motor actions to avoid misunderstanding during one of the most multifaceted and risky social interaction.

关键词： Crocuta crocuta head and facial signals head bobbing metacommunication play fighting relaxed open mouth display

Influence of Surface Finishing on High-Temperature Oxidation of AISI Type 444 Ferritic Stainless Steel Used in SOFC Stacks

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 697-711页

作者： Valeria Bongiorno paolo Piccardo Simone Anelli Roberto Spotorno Laboratorio di Metallurgia e Materiali - Dipartimento di Chimica e Chimica Industriale (LMM-DCCI) Universita degli Studi di Genova Via Dodecaneso 31 16146 GenoaItaly

This research is focused on the study of the samples, approximatively 15 × 30 mm^2 sized, that were mechanically cut from two sheets （0.4 and 0.2 mm thick, respectively） of AIS1444 Type ferritic stainless steel （FSS）（DIN 1.4521, Eu designation X2CrMoTil8-2）; this material was in the ＇as-rolled＇ state. Part of these specimens were treated superficially on one side using abrasive SiC papers with different average grit sizes （i.e., 46.2, 30.2, 18.3 gm） and diamond suspension （up to 1 tim） in order to obtain various surface roughness. Both the ＇as-rolled＇ and superficially treated samples were then aged in a muffle fumace in static air according to a thermal cycle corresponding to the curing phase of an experimental glass used as sealing in the solid oxide fuel cell stacks. After aging, the chemical compositions and mor- phological peculiarities of the scale formed depending on the thickness of the samples and their surface state were studied by scanning electron microscopy, energy-dispersive spectroscopy, micro-Raman spectroscopy, bright field light optical microscopy. The obtained results show that all scales formed consist of an inner Cr2O3 subscale and an outer （Mn,Cr）3O4 spinel layer; the relationship between FSS grain size and scale microstructural features is consistent on the samples with mirror-like surface only; the scale thicknesses on SiC grinded samples are comparable; the scales covering the ＇as-rolled＇ surfaces are morphologically similar to those grown on the surfaces finished with the 30.2 and 18.3 μm SiC papers, and their thicknesses show an intermediate situation between the abraded and the mirror-like specimens. The last described characteristics depend mainly on the surface and microstructural peculiarities resulting from the rolling process.

关键词： AISI Type 444 SOFC stacks Surface roughness Microstructure Surface finishing High-temperature oxidation

CNTs tuning and vertical alignment in anodic aluminium oxide membrane

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Journal of Natural Gas Chemistry 2012年第6期21卷 639-646页

作者： Maria Sarno Diana Sannino Caterina Leone paolo Ciambelli Department of Industrial Engineering and Centre NANO MATES University of Salerno

Anodic aluminium oxide （AAOM） membranes were used for template growth of carbon nanotubes （CNT） inside their pores by chemical vapour deposition （CVD） of different hydrocarbons, in the absence of transition metal catalyst. A composite material, containing one nanotube for each channel, having the same length as the membrane thickness and the external diameter close to the diameter of the membrane holes, was obtained. Yield, selectivity, and quality of CNTs in terms of diameter （up to very thin CNT）, carbon order, length, arrangement （i.e. number of tubes for each channel）, purity, that are critical requisites for several applications were optimised by investigating the effect of changing the hydrocarbon feedstock gas, also in the presence of hydrogen. The samples produced using methane as a feedstock have a well ordered structure. The role of the alumina channels surface during the CNT growth has been investigated and its catalytic activity has been proved for the first time.

关键词： catalysis chemical processes nanomaterials microreactor hydrocarbons CVD controlled CNTs synthesis

Spectral and fragility evaluations of retrofitted structures through strength reduction and enhanced damping

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 115-125页

作者： Gian paolo Cimellaro Hwasung Roh Alessandro De Stefano Department of Structural & Geotechnical Engineering (DISTR) Polytechnic of Turin Turin Italy Department of Civil Structural & Environmental Engineering University at Buffalo The State University of New York Buffalo USA

A retrofit procedure for existing buildings called the ＂weakening and damping technique＂（WED） is presented in this paper. Weakening of structures can limit the maximum response accelerations during severe ground motions, but leads to an increase in the displacements or inter-story drifts. Added damping by using viscous dampers, on the other hand, reduces the inter-story drifts and has no significant effect on total accelerations, when structures behave inelastically. The weakening and damping technique addresses the two main causes for both structural and nonstructural damage in structures. The weakening retrofit is particularly suitable for structures that have overstressed components and weak brittle components. In this paper, the advantages of the WeD are verified by nonlinear dynamic analysis and simplified spectral approach that has been modified to fit structures with additional damping devices. A hospital structure located in the San Fernando Valley in California is selected as a case study. The results from both analyses show that the retrofit solution is feasible to reduce both structural acceleration and displacement. A sensitivity analysis is also carried out to evaluate the effectiveness of the retrofitting method using different combinations of performance thresholds in accelerations and displacements through fragility analysis.

关键词： weakening damping retrofit inelastic spectral response fragility analysis nonlinear dynamic analysis