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Repeat-pass space-surface bistatic SAR tomography:accurate imaging and first experiment

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Science China(Information Sciences) 2024年第9期67卷 245-262页

作者： Zhiyang CHEN Yuanhao LI Cheng HU Shenglei WANG Xinpeng CHEN Mihai DATCU Andrea virgilio MONTI-GUARNIERI Radar Technology Research Institute School of Information and Electronics Beijing Institute of Technology Beijing Key Laboratory of Embedded Real-Time Information Processing Technology Beijing Institute of Technology Advanced Technology Research Institute Beijing Institute of Technology CEOSpace Tech University Politehnica of Bucharest Dipartimento di Elettronica Informazione e Bioingegneria Politecnico di Milano

Space-surface bistatic synthetic aperture radar(SS-BiSAR) offers an additional observation angle for monostatic spaceborne SAR, making it a promising technology for high-accuracy deformation retrieval technology in local regions. Repeat-pass SS-BiSAR tomography can accurately estimate the surfaces of buildings and steep areas, effectively removing terrain phases during deformation retrieving. However, inaccuracies in the orbital ephemeris can lead to image geometry distortion, reducing image pair coherence,introducing interferometric phase errors, and consequently deteriorating tomographic precision. This paper precisely models the image geometry distortion and interferometric phase error caused by repeat-pass ephemeris error. We propose an ephemeris correction method based on the chirp-Z transform to address these issues. Furthermore, we introduce an accurate tomography model to improve 3D reconstruction *** first SS-BiSAR tomography experiment, conducted using the Chinese Lutan-1 satellite, demonstrates that the correlation coefficient is improved by 0.16 after ephemeris error correction. Moreover, the density and precision of the tomographic point cloud are improved by 13.7% and 12.1%, respectively.

关键词： space-surface SAR tomography orbit error image distortion Lutan-1

A theory of very short-time price change:security price drivers in times of high-frequency trading

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Financial Innovation 2022年第1期8卷 1800-1833页

作者： Gianluca P.M.virgilio Universidad Católica Sedes Sapientiae Nueva CajamarcaPeru

Academic research has identified several factors that affect price movements;however,the scenario changes abruptly in the case of very short time price changes(VSTPC).This topic is not specifically examined in the existing literature;nonetheless,the behavior of the market microstructure is quite different at the subsecond ***,below a certain psychological time threshold,most factors typically influencing price changes cease to *** paper analyzes several parameters considered to affect price changes and identifies four of them as potentially influencing *** factors are previous volatility,scarce liquidity,high quantity exchanged,and stop-loss(SL)orders(seldom mentioned in the literature).These four parameters are examined by means of a mathematical model,audit trail data analysis,Granger-causality testing,and agent-based *** results of these four techniques converge to suggest a nonlinear combination of previous volatility,liquidity,and SL orders as the main causes of excess ***,contrary to mainstream literature on trading time above a certain psychological threshold,the volumes exchanged are not integral agents for ***,financial markets face many ultrafast orders,yet a coherent theory of price change at time scales incomprehensible by humans and only manageable by computers is still *** theory presented in this paper attempts to fill this *** outcome of such a theory is important for purposes of market stability,crisis avoidance,investment planning,risk management,and high-frequency trading.

关键词： High-frequency trading Subsecond time scale Volatility Liquidity Exchange volume Stop-loss orders

Puma （Puma concolor） epididymal sperm morphometry

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Asian Journal of Andrology 2016年第6期18卷 879-881页

作者： Hernan Cucho virgilio Alarcon Cesar Ordonez Enrique Ampuero Aydee Meza Caries Solere Zootechny School National University of San Atonio Abad del Cusco Postal code 921 Cusco Peru Functional Biology and Physical Anthropology Department University of Valencia C/. Dr Moliner 50 46100 Burjassot Valencia Spain Proiser R+D S.L. Scientific Park of the University of Valencia 46980 Paterna Spain

The Andean puma （Puma concolor） has not been widely studied, particularly in reference to its semen characteristics. The aim of the present study was to define the morphometry of puma sperm heads and classify their subpopulations by cluster analysis. Samples were recovered postmortem from two epididymides from one animal and prepared for morphological observation after staining with the Hemacolor kit. Morphometric data were obtained from 581 spermatozoa using a CASA-Morph system, rendering 13 morphometric parameters. The principal component （PC） analysis was performed followed by cluster analysis for the establishment of subpopulations. Two PC components were obtained, the first related to size and the second to shape. Three subpopulations were observed, corresponding to elongated and intermediate-size sperm heads and acrosomes, to large heads with large acrosomes, and to small heads with short acrosomes. In conclusion, puma spermatozoa showed no uniform sperm morphology but three clear subpopulations. These results should be used for future work in the establishment of an adequate germplasm bank of this species.

关键词： principal component analysis puma sperm morphometry subpopulation wild animal

The occlusal plane in the facial context:inter-operator repeatability of a new three-dimensional method

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International Journal of Oral Science 2012年第1期4卷 34-37页

作者： Riccardo Rosati Alberto Rossetti Marcio De Menezes virgilio F Ferrario Chiarella Sforza Department of Human Morphology Universita` degli Studi di MilanoMilano 20133Italy

The repeatability of a non-invasive digital protocol proposed to evaluate the three-dimensional（3D） position of the occlusal plane in the face is *** virtual models and soft tissue facial morphology of 20 adult subjects were digitally integrated using a 3D stereophotogrammetric imaging *** digital 3D coordinates of facial and dental landmarks were obtained by two different ***＇s（facial） and occlusal（dental） planes were individuated,and their 3D relationships were *** repeatability of the protocol was investigated and showed no significant differences in repeated *** angle between occlusal and Camper＇s planes was smaller than 26 in the frontal and horizontal *** the sagittal projection,the angle was observed to be,on average,4.9 *** determined occlusal plane pitch,roll and yaw values show good agreement with previously published data obtained by different *** current non-invasive method was repeatable,without inter-operator differences and can facilitate assessment of healthy subjects.

关键词： healthy subjects occlusal plane stereophotogrammetry three-dimensional analysis

Malaria epidemiology in the Democratic Republic of East Timor

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Asian Pacific Journal of Tropical Medicine 2010年第4期3卷 283-287页

作者： Afonso de Almeida virgilio E do Rosario Ana Paula Arez Pedro Cravo Universidade Nacional de Timor Lorosae Avenida Cidade de LisboaDili-Timor Leste Centro de Malaria e Outras Doencas Tropicais Instituto de Higiene e Medicina TropicalUniversidade Nova de LisboaRua da Junqueira 961349-008 Lisboa Portugal Centro de Malaria e Outras Doencas Tropicais Instituto de Higiene e Medicina TropicalUniversidade Nova de LisboaRua da Junqueira 961349008 Lisboa Portugal Unidade de Biologia Molecular Instituto de Higiene e Medicina TropicalUniversidade Nova de LisboaRua da Junqueira 961349-008 Lisboa Portugal

Objective:To investigate malaria prevalence and socio-economic conditions in East Timor. Methods:Blood samples were collected from 650 individuals distributed among six districts in East Timor.434 and 216 individuals were sampled by passive and active case detection, respectively(PCD,ACD).Results:The results showed that the plasmodium infection prevalence was 18.9%with predominance of Plasmodium falciparum(***) infections(60.2%). The majority of cases were detected in children between 2-14 years old in both PCD and ACD. Participants residing in Same and Lospalos were at a higher risk of *** percentage of infections associated to the lack of bed net use was twice as high as users(25.2%vs 12.5%). The prevalence of malaria among participants who lived in brick/cement houses(8.3%) was two times less than those who lived in other types of houses(3.7%).There was a significantly lower prevalence of infection detected in individuals living in complete housing constructions with absence of domestic animals in or near the ***:The major risk factors for malaria in East Timor are age,lack of bed net use,incomplete housing constructions and exposure to mosquitoes.

关键词： East Timor Malaria epidemiology Children Risk factors Housing constructions

Protein Domains Involved in Assembly in the Endoplasmic Reticulum Promote Vacuolar Delivery when Fused to Secretory GFP, Indicating a Protein Quality Control Pathway for Degradation in the Plant Vacuole

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Molecular Plant 2008年第6期1卷 1067-1076页

作者： Ombretta Foresti Francesca De Marchis Maddalena de virgilio Eva M. Klein Sergio Arcioni Michele Bellucci Alessandro Vitale Istituto di Biologia e Biotecnologia Agraria Consiglio Nazionale delle Ricerche via Bassini 15 20133 Milano Italy EU Istituto di Genetica Vegetale Consiglio Nazionale delle Ricerche via della Madonna Alta 130 06128 Perugia Italy EU

The correct folding and assembly of newly synthesized secretory proteins are monitored by the protein quality control system of the endoplasmic reticulum （ER）. Through interactions with chaperones such as the binding protein （BiP） and other folding helpers, quality control favors productive folding and sorts for degradation defective proteins. A major route for quality control degradation identified in yeast, plants, and animals is constituted by retrotranslocation from the ER to the cytosol and subsequent disposal by the ubiquitin/proteasome system, but alternative routes involving the vacuole have been identified in yeast. In this study, we have studied the destiny of sGFP418, a fusion between a secretory form of GFP and a domain of the vacuolar protein phaseolin that is involved in the correct assembly of phaseolin and in BiP recognition of unassembled subunits. We show that sGFP418, despite lacking the phaseolin vacuolar sorting signal, is delivered to the vacuole and fragmented, in a process that is inhibited by the secretory traffic inhibitor brefeldin A. Moreover, a fusion between GFP and a domain of the maize storage protein γ-zein involved in zein polymerization also undergoes post-translational fragmentation similar to that of sGFP418. These results show that defective secretory proteins with permanently exposed sequences normally involved in oligomerization can be delivered to the vacuole by secretory traffic. This strongly suggests the existence of a plant vacuolar sorting mechanism devoted to the disposal of defective secretory proteins.

关键词： Endoplasmic reticulum protein degradation protein traffic vacuole.

Endoscopic ultrasound-guided treatments: Are we getting evidence based- a systematic review

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World Journal of Gastroenterology 2014年第26期20卷 8424-8448页

作者： Carlo Fabbri Carmelo Luigiano Andrea Lisotti Vincenzo Cennamo Clara virgilio Giancarlo Caletti Pietro Fusaroli Unit of Gastroenterology and Digestive Endoscopy AUSL Bologna Bellaria-Maggiore Hospital Unit of Gastroenterology and Digestive Endoscopy Department of Medical and Surgical Sciences - DIMEC University of BolognaHospital S Maria della Scaletta

The continued need to develop less invasive alternatives to surgical and radiologic interventions has driven the development of endoscopic ultrasound(EUS)-guided *** include EUS-guided drainage of pancreatic fluid collections,EUS-guided necrosectomy,EUS-guided cholangiography and biliary drainage,EUSguided pancreatography and pancreatic duct drainage,EUS-guided gallbladder drainage,EUS-guided drainage of abdominal and pelvic fluid collections,EUS-guided celiac plexus block and celiac plexus neurolysis,EUSguided pancreatic cyst ablation,EUS-guided vascular interventions,EUS-guided delivery of antitumoral agents and EUS-guided fiducial placement and *** these procedures are technically challenging and require expertise in both EUS and interventional endoscopy,such as endoscopic retrograde cholangiopancreatography and gastrointestinal *** undertook a systematic review to record the entire body of literature accumulated over the past 2decades on EUS-guided interventions with the objective of performing a critical appraisal of published articles,based on the classification of studies according to levels of evidence,in order to assess the scientific progress made in this field.

关键词： Endoscopic ultrasound Pseudocyst drainage Necrosectomy Celiac plexus neurolysis Levels of evidence Fine needle injection

In Vivo Toxicity Assessment of Gold Nanoparticles in Drosophila melanogaster

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Nano Research 2011年第4期4卷 405-413页

作者： Pier Paolo Pompa Giuseppe Vecchio Antonio Galeone virgilio Brunetti Stefania Sabella Gabriele Maiorano Andrea Falqui GiovanniBertoni Roberto Cingolani Italian Institute of Technology Center for Bio-Molecular Nanotechnology Via Barsanti 1-73010 Arnesano （Lecce） Italy Italian Institute of Technology Central Research Laboratories Via Morego 30-16136 Genova Italy

The growing use of nanomaterials in commercial goods and novel technologies is generating increasing questions about possible risks for human health and environment, due to the lack of an in-depth assessment of their potential toxicity. In this context, we investigated the effects of citrate-capped gold nanoparticles （AuNPs） on the model system Drosophila melanogaster upon ingestion. We observed a significant in vivo toxicity of AuNPs, which elicited clear adverse effects in treated organisms, such as a strong reduction of their life span and fertility, presence of DNA fragmentation, as well as a significant overexpression of the stress proteins. Transmission electron microscopy demonstrated the localization of the nanoparticles in tissues of Drosophila. The experimental evidence of high in vivo toxicity of a nanoscale material, which is widely considered to be safe and biocompatible in its bulk form, opens up important questions in many fields, including nanomedicine, material science, health, drug delivery and risk assessment.

关键词： Nanoparticles nanotoxicology gold in vivo studies

The Yin-Yang of osteopontin in nervous system diseases: damage versus repair

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Neural Regeneration Research 2021年第6期16卷 1131-1137页

作者： Giuseppe Cappellano Domizia Vecchio Luca Magistrelli Nausicaa Clemente Davide Raineri Camilla Barbero Mazzucca Eleonora virgilio Umberto Dianzani Annalisa Chiocchetti Cristoforo Comi Department of Health Sciences Interdisciplinary Research Center of Autoimmune Diseases(IRCAD)University of Piemonte OrientaleNovaraItaly Center for Translational Research on Autoimmune and Allergic Disease-CAAD University of Piemonte OrientaleNovaraItaly Department of Translational Medicine Neurology UnitInterdisciplinary Research Center of Autoimmune Diseases(IRCAD)University of Piemonte OrientaleNovaraItaly PhD Program in Clinical and Experimental Medicine and Medical Humanities University of InsubriaVareseItaly

Osteopontin is a broadly expressed pleiotropic protein,and is attracting increased attention because of its role in the pathophysiology of several inflammatory,degenerative,autoimmune,and oncologic *** fact,in the last decade,several studies have shown that osteopontin contributes to tissue damage not only by recruiting harmful inflammatory cells to the site of lesion,but also increasing their *** detrimental role of osteopontin has been indeed well documented in the context of different neurological conditions(i.e.,multiple sclerosis,Parkinson’s,and Alzheimer’s diseases).Intriguingly,recent findings show that osteopontin is involved not only in promoting tissue damage(the Yin),but also in repair/regenerative mechanisms(the Yang),mostly triggered by the inflammatory *** two apparently discordant roles are partly related to the presence of different functional domains in the osteopontin molecule,which are exposed after thrombin or metalloproteases *** functional domains may in turn activate intracellular signaling pathways and mediate cell-cell and cell-matrix *** review describes the current knowledge on the Yin and Yang features of osteopontin in nervous system *** the mechanisms behind the Yin/Yang would be relevant to develop highly specific tools targeting this multifunctional protein.

关键词： Alzheimer’s disease cytokine immunity microglia multiple sclerosis neuroinflammation neuroprotection neurotoxicity Parkinson’s disease Spp1 stroke