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Tight-binding models for ultracold atoms in optical lattices：general formulation and applications

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Science China(Physics,Mechanics & Astronomy) 2016年第6期59卷 1-23页

作者： michele Modugno Julen Ibanez-Azpiroz Giulio Pettini Departamento de Fisica Teorica e Historia de la Ciencia Universidad del Pais Vasco UPV/EHU Bilbao 48080 Spain IKERBASQUE Basque Foundation for Science Bilbao 48011 Spain Peter Griinberg Institute and Institute for Advanced Simulation Forschungszentrum Jiilich & JARA Jiilich D-52425 Germany Dipartimento di Fisica e Astronomia Universita di Firenze and INFN Sesto Fiorentino 50019 Italy

Tight-binding models for ultracold atoms in optical lattices can be properly defined by using the concept of maximally localized Wannier functions for composite bands. The basic principles of this approach are reviewed here, along with different applications to lattice potentials with two minima per unit cell, in one and two spatial dimensions. Two independent methods for computing the tight-binding coefficients—one ab initio, based on the maximally localized Wannier functions, the other through analytic expressions in terms of the energy spectrum—are considered. In the one dimensional case, where the tight-binding coefficients can be obtained by designing a specific gauge transformation, we consider both the case of quasi resonance between the two lowest bands, and that between s and p orbitals. In the latter case, the role of the Wannier functions in the derivation of an effective Dirac equation is also reviewed. Then, we consider the case of a two dimensional honeycomb potential, with particular emphasis on the Haldane model, its phase diagram, and the breakdown of the Peierls substitution. Tunable honeycomb lattices, characterized by movable Dirac points, are also considered. Finally, general considerations for dealing with the interaction terms are presented.

关键词： ultracold atoms optical lattices tight-binding models Wannier functions effective Dirac equation honeycomb lattices

Covariation between plant biodiversity and soil systems in a European beech forest and a black pine plantation:the case of Mount Faito,(Campania,Southern Italy)

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Journal of Forestry Research 2022年第1期33卷 239-252页

作者： Tiziana Danise michele Innangi Elena Curcio Antonietta Fioretto Department of Environmental Biological and Pharmaceutical Sciences and TechnologiesUniversity of Campania“Luigi Vanvitelli”Via Vivaldi 4381100 CasertaItaly

Both climate and land-use changes,including the introduction and spread of allochthonous species,are forecast to affect forest ***,forests will be affected in terms of species composition as well as their soil chemical and biological *** possible changes in both tree cover and soil system might impact the amount of carbon that is stored in living plants and dead biomass and within the soil ***,such alterations can have a strong impact on the detrital food web that is linked to litter *** there are studies on the infuence of plant diversity on soil physical and chemical characteristics,the effects on soil biological activity and carbon storage processes remain largely *** aim of this study was to investigate and compare chemical and biological variables in covariation with plant communities in an autochthonous beech forest(Fagus sylvatica L.)and a black pine plantation(Pinus nigra *** ***).Our results confirmed that the two communities were considerably different,with the old-growth beech community having a lower number of plant species and the pine community was in development as a consequence of anthropogenic *** aspects of the two communities were also refected in the soil,with the beech soil having higher nitrogen levels and a more specialized microbial community compared to the pine soil,with most extracellular enzymes(such as peroxidase and chitinase)showing lower activity in the pine soil.

关键词： 2B-PLS Plant and soil Vegetation Soil enzymes

Choroidal vascularity index in thyroidassociated ophthalmopathy:a crosssectional study

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Eye and Vision 2021年第4期8卷 175-182页

作者： Pasquale Loiudice Marco Pellegrini michele Marinò Barbara Mazzi Ilaria Ionni Giuseppe Covello michele Figus Marco Nardi Giamberto Casini Department of Surgical Ophthalmology UnitMedicalMolecular and Critical Area PathologyUniversity of PisaVia Savi1056126 PisaItaly Ophthalmology Unit S.Orsola-Malpighi University HospitalUniversity of BolognaBolognaItaly Department of Clinical and Experimental Medicine Endocrinology Unit IUniversity Hospital of PisaPisaItaly

Background:Hemodynamic changes have been observed in patients with Graves’*** aim of our study was to evaluate choroidal vascular change using the choroidal vascularity index(CVI)in patients with thyroidassociated ophthalmopathy(TAO).Methods:In this cross-sectional observational study,40 patients affected by TAO were *** healthy individuals,matched for age and sex,served as *** enhanced-depth imaging optical coherence tomography scans were obtained from all *** were binarized using the ImageJ software and luminal area(LA)and total choroidal area(TCA)were *** was calculated as the proportion of LA to *** relation between CVI or subfoveal choroidal thickness(SFCT)and clinical activity score,exophthalmometric value,diplopia status,gender,and age was ***:CVI was significantly higher in patients with TAO(P=0.004).No significant difference was observed in SFCT(P=0.200)and TCA(P=0.153)comparing TAO patients and healthy *** was significantly higher in TAO group(P=0.045).On multiple regression analysis,CVI was associated with TCA(P=0.043).No association was found between SFCT or CVI and TCA,clinical activity score,exophthalmometric value,Inami value,diplopia status,gender or age(P>0.05).Conclusions:This is the first study that has demonstrated an increase in CVI in eyes with TAO compared with healthy controls and has assessed its association with clinical features.

关键词： Choroidal vascularity index Choroidal vasculature Enhanced depth optical coherence tomography Image binarization Luminal area Subfoveal choroidal thickness Thyroid-associate ophthalmopathy

Asymptotic Derivation of a Linear Plate Model for Soft Ferromagnetic Materials

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Chinese Annals of Mathematics,Series B 2018年第3期39卷 451-460页

作者： Giuseppe GEYMONAT Francoise KRASUCKI michele SERPILLI Laboratoire de Mecanique des Solides Ecole PolytechniqueCNRSUniversite Paris-Saclay91128 PalaiseauFrance Institut Montpellierain Alexander Grothendieck UMR-CNRS 5149Universite de Montpellier Place Eugene Bataillon34095 Montpellier Cedex 5France Department of Civil and Building Engineering and ArchitecturePolytechnic University of MarcheVia Brecce Bianche60131 AnconaItaly

The authors use the asymptotic expansion method by *** to obtain a Kirchhoff-Love-type plate model for a linear soft ferromagnetic *** also give a mathematical justification of the obtained model by means of a strong ... 详细信息

关键词： Asymptotic methods Plates Magnetoelasticity

Morphology, flight performance, and water crossing tendencies of Afro-Palearctic raptors during migration

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Current Zoology 2015年第6期61卷 951-958页

作者： Nicolantonio AGOSTINI michele PANUCCIO Cristian PASQUARETTA MEDRAPTORS (Mediterranean Raptor Migration Network) Via Mario Fioretti 18 00152 Rome Italy University of Pavia Department of Earth and Environmental Sciences Via Ferrata 9 27100 Pavia (PV) Italy Universit6 de Strasbourg IPHC 23 rue Becquerel 67087 Strasbourg France CNRS UMR7178 67037 Strasbourg France

Raptors primarily use soaring-gliding flight which exploits thermals and ridge lifts over land to reduce energetic costs However during migration, these birds often have to cross water surfaces where thermal currents are weak; during these times, birds mainly use flapping （powered） flight which increases energy consumption and mortality risk. As a result, some species have evolved strategies to reduce the amount of time spent over water by taking extensive detours over land. In this paper, we con- ducted a meta-analysis of water-crossing tendencies in Afro-Palearctic migrating raptors in relation to their morphology, their flight performance, and their phylogenetic relationships. In particular, we considered the aspect ratio （calculated as the wing span squared divided by wing area）, the energetic cost of powered flight, and the maximum water crossing length regularly performed by adult birds. Our results suggest that energy consumption during powered flight predominately affects the ability of raptors to fly over water surfaces

关键词： Water crossing Aspect ratio Powered flight Migration Raptors Wing tip

Alpha-Klotho in Parkinson’s disease: a perspective on experimental evidence and potential clinical implications

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Neural Regeneration Research 2022年第12期17卷 2687-2688页

作者： Piergiorgio Grillo michele Basilicata Tommaso Schirinzi Unit of Neurology Department of Systems MedicineUniversity of Roma Tor VergataRomeItaly Department of Experimental Medicine and Surgery University of Roma Tor VergataRomeItaly

more than 20 years ago,and immediately emerged as a master regulator of aging-related processes,which basically operates as an anti-aging *** is expressed through the entire human body,representing the choroid plexus and the kidney as the most active sources at the central nervous system(CNS)and periphery level *** a lesser extent,also the parathyroid gland,the adipose tissue,and the liver express *** is a transmembrane protein serving as an essential co-receptor for fibroblast growth factor receptors,but,in general,it mediates a number of molecular pathways and biological functions at a multisystem *** fact,even a soluble form exists,originated by the extracellular domain cleavage,which circulates in human fluids,allowing a sort of systemic *** all the tissue-specific actions have not been completely clarified,there is solid evidence that KL regulates basic mineral homeostasis and internal metabolism pathways.

关键词： metabolism Klotho homeostasis

Neurogenesis in the adult peripheral nervous system

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Neural Regeneration Research 2012年第14期7卷 1047-1054页

作者： Krzysztof Czaja michele Fornaro Stefano Geuna Department of Veterinary and Comparative Anatomy Pharmacology and Physiology (VCAPP) College of Veterinary Medicine Washington State University Pullman WA 99163-6520 USA Department of Anatomy Chicago College of Osteopathic Medicine (CCOM) Midwestern University Downers Grove IL 60515 USA Neuroscience Institute of the Cavalieri Ottolenghi Foundation (NICO) & Department of Clinical and Biological Sciences University of Turin Orbassano 10043 Italy

Most researchers believe that neurogenesis in mature mammals is restricted only to the subgranular zone of the dentate gyrus and the subventricular zone of the lateral ventricle in the central nervous system. In the peripheral nervous system, neurogenesis is thought to be active only during prenatal development, with the exception of the olfactory neuroepithelium. However, sensory ganglia in the adult peripheral nervous system have been reported to contain precursor cells that can proliferate in vitro and be induced to differentiate into neurons. The occurrence of insult-induced neurogenesis, which has been reported by several investigators in the brain, is limited to a few recent reports for the peripheral nervous system. These reports suggest that damage to the adult nervous system induces mechanisms similar to those that control the generation of new neurons during prenatal development. Understanding conditions under which neurogenesis can be induced in physiologically non-neurogenic regions in adults is one of the major challenges for developing therapeutic strategies to repair neurological damage. However, the induced neurogenesis in the peripheral nervous system is still largely unexplored. This review presents the history of research on adult neurogenesis in the peripheral nervous system, which dates back more than 100 years and reveals the evidence on the under estimated potential for generation of new neurons in the adult peripheral nervous system.

关键词： adult neurogenesis peripheral nervous system dorsal root ganglia autonomic ganglia stem cells mammals

Ambient Affiliation in Comments on YouTube Videos:Communing Around Values About ASMR

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外国语 2021年第1期44卷 21-40页

作者： michele Zappavigna University of New South Wales SydneyAustralia

This paper explores ambient affiliation within the ASMR community on YouT ube,investigating how values are communed around in YouT ube *** community consists of viewers who watch videos designed to elicit an Autonomous Sensory Meridian Response(ASMR),that is,a pleasurable sensory reaction to visual or aural *** paper focuses on the linguistic resources involved in orienting the ambient audience to the values shared,as couplings of ATTITUDE and IDEATION,in the comments *** most comments do not receive any reply,rather than dialogic affiliation,a framework for analysing communing affiliation,based on Zappavigna and Martin’s(2018)approach to Twitter data,is *** systems of meaning are considered:convoking(mustering community around a coupling),finessing(dialogically positioning a coupling),and promoting(emphasising a coupling).The paper develops these systems in terms of *** attitudinal component of the couplings is analysed using the Appraisal framework(Martin and White 2005).The dataset explored is the comments feed of the most viewed video on the Gentle Whispering ASMR YouT ube channel,the most popular ASMR channel at the time of writing.

关键词： ambient affiliation communing affiliation coupling appraisal digital intimacy ASMR YouTube

Adjuvant treatment in biliary tract cancer: To treat or not to treat?

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World Journal of Gastroenterology 2012年第21期18卷 2591-2596页

作者： Stefano Cereda Carmen Belli michele Reni Department of Oncology San Raffaele Scientific Institute20132 Milan Italy

Biliary tract cancer is a rare malignant tumor. There is limited knowledge about biology and natural history of this disease and considerable uncertainty remains regarding its optimal diagnostic and therapeutic man- agement. The role of adjuvant therapy is object of debate and controversy. Although resection is identified as the most effective and the only potentially curative treatment, there is no consensus on the impact of ad- juvant chemotherapy and/or radiotherapy on the high incidence of disease recurrence and on survival. This is mainly due to the rarity of this disease and the consequent difficulty in performing randomized trials. The only two prospectively controlled trials concluded that adjuvant chemotherapy did not improve survival. Most of the retrospective trials, which had limited sample size and included heterogeneous patients population and non-standardized therapies, suggested a marginal benefit of chemoradiotherapy in reducing locoregional recurrence and an uncertain impact on survival. Welldesigned multi-institutional randomized trials are necessary to clarify the role of adjuvant therapy. Two ongoing phase Ⅲ trials may provide relevant information.

关键词： Biliary tract cancer Adjuvant therapy Chemotherapy Chemoradiation Surgery