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Color variation in signal crayfish Pacifastacus leniusculus

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Current Zoology 2021年第1期67卷 35-43页

作者： roberto sacchi Stefania CANCIAN Daniela GHIA Gianluca FEA Alan COLADONATO Dipartimento di Scienze della Terra e dell'Ambiente Universita degli Studi di PaviaViale Tarameli 24Pavia1-27100Italy

External coloration in animals depends on the interaction of several different factors including the genetics and epigenetics processes that underlie the color expression,the mechanisms of color perception,and the general mechanisms controlling color evolution and *** all,camouflages from predators and conspicuousness are of particular interest because pose animal to choose between opposite adjustment in *** external coloration of crustaceans is mainly due to the accumulation of carotenoids in the exoskeleton and the epidermal layer,and the trade-off between camouflage and communication had led to a variety of responses,involving signal partitioning,spectral sensibility,changing coloration,or signaling ***,we used digital images to explore intrapopulation variability of the external coloration of Pacifastacus leniusculus among body regions within an individual and between *** found that 1)ventral coloration of claws are more saturated and brilliant than upper parts,2)males express a more saturated and brightness coloration than females,especially on the lower portion of claws,3)color intensity and brightness increases with size differently in different body regions,and 4)brightness is more variable in males than in *** the above patterns support the hypothesis that color in this species could be the result of a compromise between camouflage from predators and conspicuousness for *** results of this study suggest that carotenoid might have something to do with intraspecific communication and perform more complex functions than that of a simple pigment.

关键词： crayfish external coloration HSV individual variation sexual dimorphism

Morph-specific assortative mating in common wall lizard females

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Current Zoology 2018年第4期64卷 449-453页

作者： roberto sacchi Alan Jioele COLADONATO Michele GHITTI Marco MANGIACOTTI Stefano SCALI Matteo Bovo Marco ZUFFI Dipartimento di Scienze della Terra e delrAmbiente Università degli Studi di Pavia Via Taramelli 24 Pavia 1-27100 Italy Museo di Storia Naturale di Milano Corso Venezia 55 Milano 1-20121 Italy Museo di Storia Naturale Università di Pisa Via Roma 79 Calci 1-56011 Italy di Pisa Via Roma 79 Calci 1-56011 Italy

Color polymorphism often is associated with alternative reproductive strategies and may reflect different adaptive optima that coexist within populations. The equilibrium among morph frequencies is maintained by the occurrence of opposite selective pressures （disruptive vs. stabilizing）, which promote polymorphism while preserving gene flow. Sexual selection may contribute on both sides, particularly when morphs do not mate randomly. Reptiles offer a good model, notably lizards. Nevertheless, previous studies on mate choice in polymorphic lizards have generated contrasting results, with some studies suggesting that female morphs might tune their preference depending on environmental/social conditions such as crowding. We experimentally manipulated the number of individuals a female common wall lizard Podarcis muralis perceives around her, to test if females of different morphs （white or yellow） tune their choice for white and yellow males in order to maximize the probability that hatchlings follow the strategy best adapted to the population density. Results showed that crowding experienced by females did not affect mate choice, arguing against a flexible choice strategy by females. However, white females significantly associated with white males, whereas yellow females did not significantly associate with yellow males. Thus, sexual selection could contribute to the maintenance of color polymorphism in this species by a mix of assortative and non-assortative mating strategies, which could maintain the equilibrium between gene divergence and gene flow among morphs.

关键词： flexible female choice population density color polymorphism sexual selection

Inter- and intra-population variability of the protein content of femoral gland secretions from a lacertid lizard

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Current Zoology 2017年第6期63卷 657-665页

作者： Marco MANGIACOTTI Marco FUMAGALLI Stefano SCALI Marco A.L. ZUFFI Maddalena CAGNONE Roberta SALVINI roberto sacchi Department of Earth and Environmental Sciences University of Pavia Via Taramelli 24 Pavia 1-27100 Italy Museo Civico di Storia Naturale di Milano Corso Venezia 55 Milano 1-20121 Italy Department of Biology and Biotechnology "L. Spallanzani" Biochemistry Unit University of Pavia Via Taramelli 3 Pavia 1-27100 Italy Museo di Storia Naturale Universita di Pisa Via Roma 79 Calci Pisa 1-56011 Italy Department of Molecular Medicine Biochemistry Unit University of Pavia Via Taramelli 3 Pavia 1-27100 Italy

Femoral glands of male lizards produce waxy secretions that are involved in inter- and intraspecific chemical communication. The main components of these secretions are proteins and lipids, the latter having been extensively studied and already associated to male quality. On the opposite, the composition and role of proteins are nearly unknown, the only available information coming from few studies on iguanids. These studies got the conclusion that proteins might have a communicative function, notably they could signal individual identity. A generalization of these findings requires the extension of protein analysis to other lizard families, and the primary detection of some patterns of individual variability. Using the common wall lizard Podarcis muralis as a model species, the protein fraction of the femoral pore secretions was investigated to provide the first characterization of this component in a lacertid lizard and to explore its source of variability, as a first step to support the hypothesized communicative role. Samples of proteins from femoral secretions were collected from 6 Italian populations and subjected to 1-dimensional electrophoresis. The binary vector of the band presence/absence was used to define the individual profiles. Protein fraction is found to have a structured pattern, with both an individual and a population component. Although the former supports the potential communicative role of proteins, the latter offers a double interpretation, phylogenetic or environmental, even though the phylogenetic effect seems more likely given the climatic resemblance of the considered sites. Further studies are necessary to shed light on both these issues.

关键词： chemical communication femoral glands lizards Podarcis muralis proteins SDS-PAGE.

Development of a petroleum knowledge tutorial system for university and corporate training

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Petroleum Science 2012年第1期9卷 110-120页

作者： Verga Francesca Benetatos Christoforos sacchi Quinto Carta roberto Petroleum Engineering Group DITAG Politecnico di Torino Corso Duca degli Abruzzi 24 10129 Turin Italy HOPLO Srl2 Via San Lucifero 65 09127 Cagliari Italy

The increasingly rapid development of the disciplines of petroleum engineering and petroleum geology has led to new methodologies and interpretation techniques forming new knowledge that should be offered quickly and efficiently to modern engineers and geologists. This need is equally important for students as well as for young professionals. Access and training to all scientific information is necessary to ensure success in their future careers. Today, e-learning has become a common medium for the management and distribution of on-line educational content. Learning Management Systems （LMSs） were not only developed to handle a large variety of multimedia content that provides an organized knowledge repository used to accelerate access to information and skill acquisition; but, LMSs can also keep detailed statistics on the use of the available material offering a powerful training and educational tool. In this document, the Petroleum Knowledge Tutorial System, an LMS platform offering a variety of online educational and training options to petroleum engineers and geologists, is presented. It was created using Moodle, open- source software that can be used to create on-line courses. The platform covers fundamental educational concepts in a structured way. It follows an optimized ＂workflow＂ that can be applied not only to solve a specific exercise but also any similar problem encountered over the course of one＇s career. The platform was designed to offer a repository of learning material in various forms and to favor user-platform interactions. It can be used for training and evaluation purposes through exercises and problem solving that the user can perform online by using browsing software along with internet access. Special tools were created and implemented on the platform to assist the user in completing a variety of tasks including performing exercises involving calculations with given data and plots of points or lines on graphs without leaving the learning envir

关键词： E-learning training petroleum engineering tutorial

NGR-tagged nano-gold： A new CD13-selective carrier for cytokine delivery to tumors

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Nano Research 2016年第5期9卷 1393-1408页

作者： Flavio Curnis Martina Fiocch Angelina sacchi Alessandro Gori Anna Gasparri Angelo Corti Division of Experimental Oncology IRCCS San Raffaele Scientific Institute Milan 20132 Italy Istituto di Chimica del Riconoscimento Molecolare CNR Milan 20131 Italy Vita Salute San Raffaele University Milan 20132 Italy

Colloidal gold （Au）, a well-tolerated several applications in nanomedicine. nanomaterial, is currently exploited for We show that gold nanoparticles tagged with a novel tumor-homing peptide containing Asn-Gly-Arg （NGR）, a ligand of CD13 expressed by the tumor neovasculature, can be exploited as carriers for cytokine delivery to tumors. Biochemical and functional studies showed that the NGR molecular scaffoldflinker used for gold functionalization is critical for CD13 recognition. Using fibrosarcorna-bearing mice, NGR-tagged nanodrugs could deliver extremely low, yet pharmacologically active doses of tumor necrosis factor （TNF）, an anticancer cytokine, to tumors with no evidence of toxicity. Mechanistic studies confirmed that CD13 targeting was a primary mechanism of drug delivery and excluded a major role of integrin targeting consequent to NGR deamidation, a degradation reaction that generates the isoAsp-Gly-Arg （isoDGR） integrin ligand. NGR-tagged gold nanoparticles can be used, in principle, as a novel platform for single- or multi-cytokine delivery to tumor endothelial cells for cancer therapy.

关键词： Asn-Gly-Arg (NGR) isoAsp-Gly-Arg (isoDGR) CD13 integrin tumor necrosis factor albumin gold nanoparticles

Dealing with pediatric glaucoma: from medical to surgical management-a narrative review

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Annals of Eye Science 2021年第3期6卷 30-36页

作者： Matteo sacchi Rosario Alfio Umberto Lizzio Gianluca Monsellato University Eye Clinic San Giuseppe HospitalMilanoItaly

Pediatric glaucoma is a potentially sight-threatening disease and is considered the second leading cause of treatable childhood *** glaucoma is a clinical entity including a wide range of conditions:primary congenital glaucoma,glaucoma secondary to ocular(e.g.,aniridia,Peter’s anomaly),or systemic disease(e.g.,Sturge Weber)and glaucoma secondary to acquired condition(pseudophakic,traumatic,uveitic glaucoma).The treatment algorithm of childhood glaucoma is a step-by-step approach,often starting with surgery,as in primary congenital glaucoma *** therapy is also crucial in the management of pediatric *** we reported the results of the randomized,controlled,clinical trials carried out in children treated with topical anti-glaucoma *** is worth knowing that prostaglandin analogues showed an excellent systemic safety profile,while serious systemic events have been reported in children taking topical *** surgery is the first surgical option in patients diagnosed with primary congenital glaucoma,with ab interno and ab externo approaches showing similar *** in children can be troublesome,as mitomycin C(MMC)can lead to bleb complications and a higher endophthalmitis rate than in *** drainage devices(GDD)are no longer a last resort and can be considered a suitable option for the management of uncontrolled pediatric glaucoma after angle surgery failure.

关键词： Pediatric glaucoma anti-glaucoma medication angle surgery trabeculectomy glaucoma drainage device(GDD)

Les "Ouvriers" subversifs de Rimbaud

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法国研究 1989年第3期 45-58页

作者： Sergio sacchi

Trés souvent chez Rimbaud le souvenir explose comme une brusque découverte: "O les énormes avenues du pays saint", dans Vies I, et dans Ouvriers: " O cette chaude matinée de févriée"-émotion á l’état pur, totale ou pour mieux dire indéfinie: le démonstratif ("cette…matinée")équivaut en effet á une description, mais seulement pour celui qui a dejá vècu cette heure unique et qui la ret-

关键词：色心王之涣切口时移

《Barbare》de Rimbaud: de la metaphore au mythe

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法国研究 1992年第1期 92-103页

作者： Sergio sacchi

作者在此文中综述了关于兰波《彩图集》中“野蛮”一诗现有的各种诠释,并在此基础上重点分析了此诗中两个含义费解的段落(第二段和第六段),试图说明隐喻如何成为变形,隐喻如何使诗歌转向神话,以及“野蛮”一诗如何引导读者超越现实,发... 详细信息

作者在此文中综述了关于兰波《彩图集》中“野蛮”一诗现有的各种诠释,并在此基础上重点分析了此诗中两个含义费解的段落(第二段和第六段),试图说明隐喻如何成为变形,隐喻如何使诗歌转向神话,以及“野蛮”一诗如何引导读者超越现实,发现本质。

关键词：隐喻重点分析综述诠释图集诗歌神话变形作者引导

"Imiter le Chinois au Coeur limpide et fin…" La Chine en France aux environs de 1860

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法国研究 1990年第1期 20-27页

作者： Sergio sacchi

Au moins depuis les merveilles révelées par Marco Polo, on peat bien dire que l′Empire du Milieu a fait rêver une vaste élite oceidentale (1). On le percoit comme le pays autre, étranger, pour ainsi dire à la nième puissance: mais cette même altérité radicale peat devenir en l′occurrence extrêmement féconde-ee qui est d′ailleurs vrai de tous lea dépaysements.

关键词：触毛