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A Method of Characterizing Radio Signal Space for Wireless Device Localization

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Tsinghua Science and Technology 2015年第4期20卷 385-408页

作者： John-Austen francisco Richard P.Martin Department of Computer Science Rutgers University

In this work we present a novel approach for describing radio signal spaces for localization algorithms. We first introduce a new metric, the Discretely Distributed Log-H61der Metric （DDLHM）. The DDLHM is designed to characterize the type and degree of signal distortion relative to Iognormal signal-to-distance path models. We first show how the DDLHM can describe and discriminate distortions in an exhaustive set of synthetic signal spaces. We then determine a reduced set of maximally diagnostic distortion parameters. Using only 4% of the maximal set of DDLHMs, we found the reduced set matches with an acceptable degree of error 95% of the time. Using the synthetic reduced set, we characterized a variety of wireless localization algorithms＇ behaviors to attenuation, bias, and multipath. We found algorithms made much different tradeoffs between best case and average case error. We then use the DDLHM to identify distortion types in three different physical environments using measured 802.11 signal strengths, and predict the positioning performance of several localization algorithms. Our approach predicts average localization error to within 2 meters of the observed average error.

关键词： radio propgation 802.11 WiFi

Palm oil biodiesel:An assessment of PAH emissions,oxidative potential and ecotoxicity of particulate matter

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Journal of Environmental Sciences 2021年第3期33卷 326-338页

作者： Silvana Arias francisco Molina John R.Agudelo Grupo de Investigación en Gestión y Modelación Ambiental-GAIA Escuela AmbientalFacultad de IngenieríaUniversidad de Antioquia UdeACalle 70 No.52-21MedellínColombia Departamento de Ingeniería Mecánica Universidad de Antioquia UdeA

This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon(PAH)compounds,oxidative potential of ascorbic acid(OP^(AA)),and ecotoxicity through D aphnia pulex mortality *** diluted with filtered fresh air(WD)gathered in a minitunel,and particulate matter(PM)collected directly from the exhaust gas stream(W/oD)were used for *** showed that PM collecting method significantly impact PAH *** all PAH appeared in both,WD and W/oD,higher concentrations were obtained in the last *** biodiesel concentration in the fuel blend decreased all PAH compounds,and those with 3 and 5 aromatic rings were the most *** biodiesel affected both OP^(AA)and *** B10 and B20 exhibited the same rate of ascorbic acid(AA)depletion,B100 showed significant faster oxidation rate during the first four minutes and oxidized 10%more AA at the end of the test.B100 and B20 were significantly more ecotoxic than *** lethal concentration LC50 for B10 was 6.13 mg/*** was concluded that palm biodiesel decreased PAH compounds,but increased the oxidative potential and ecotoxicity.

关键词： Biodiesel Particulate matter P emissions Oxidative stress Ecotoxicity Daphnia pulex

Diffusion dynamics and characterization of attogram masses in optically trapped single nanoparticles using laser-induced plasma imaging

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Nano Research 2023年第5期16卷 7470-7480页

作者： Pablo Purohit francisco J.Fortes Javier Laserna UMALASERLAB Departamento de Química AnalíticaUniversidad de MálagaC/Jiménez Fraud 4Malaga 29010Spain Niels Bohr Institute University of CopenhagenBlegdamsvej 172100 CopenhagenDenmark

In the present work,a wavelength-selected plasma imaging analysis system is presented and used to track photons emitted from single-trapped nanoparticles in air at atmospheric *** isolated nanoentities were atomized and excited into plasma state using single nanosecond laser *** use of appropriate wavelength filters alongside time-optimized acquisition settings enabled the detection of molecular and atomic emissions in the *** photon detection efficiency of the imaging line resulted in a signal>400 times larger than the simultaneously-acquired dispersive spectroscopy *** increase in sensitivity outlined the evolution of diverse physicochemical processes at the single particle scale which included heat and momentum transfer from the plasma into the particle as wells as chemical *** imaging detection of excited fragments evidenced different diffusion kinetics and time frames for atoms and molecules and their influence upon both the spectroscopic emission readout and fabrication processes using the plasma as a ***,the origin of molecular species,whether naturally-occurring or derived from a chemical reaction in the plasma,could also be studied on the basis of compositional gradients found on the *** of detection for the inspected species ranged from tens to hundreds attograms,thus leading to an exceptional sensing principle for single nanoentities that may impact several areas of science and technology.

关键词： single nanoparticle inspection wavelength-selected laser-induced plasma imaging laser fabrication attogram characterization atomic/molecular diffusion

Neuroactive alkaloids that modulate the neuronal nicotinic receptor and provide neuroprotection in an Alzheimer's disease model:the case of Teline monspessulana

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Neural Regeneration Research 2014年第21期9卷 1880-1881页

作者： Jorge Fuentealba francisco Saez-Orellana Screening of Neuroactive Compounds Laboratory Department of PhysiologyFaculty of Biological SciencesUniversity of ConcepcionChile

Despite the advances in combinatorial or synthetic chemis- try and bioinformatics, recent literature has demonstrated the relevance of nature and biomass as a source of new molecules to treat different pathologies, i.e., bioactive com- pounds obtained from Ecteinascidia turbinate to treat some types of cancer or rapamycin from Streptomyces hygroscop- icus to prevent organ rejection after transplant. This trend will continue simply due to the fact that Mother Nature has been synthesizing molecules for millions of years. In our lab- oratory, we have characterized several compounds obtained from natural sources and that possess important neuronal effects,

关键词： Neuroactive alkaloids that modulate the neuronal nicotinic receptor and provide neuroprotection in an Alzheimer’s disease model case

Macrocystic serous cystadenoma of the pancreas

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Hepatobiliary & Pancreatic Diseases International 2019年第6期18卷 587-589页

作者： Patricia Pastor Pérez francisco Miguel González Valverde francisco Pastor Quirante Department of General Surgery Reina Sofia General University Hospital University of Murcia

Cystic pancreatic lesions are common,and about 90%of these lesions are pseudocysts or retention *** cysts of the pancreas are *** majority of pancreatic serous cystadenomas are *** serous cystadenoma is an unusual and essentially benign pancreatic *** radiologic features of this subtype may resemble a pseudocyst or a mucinous ***,it is often difficult to make a correct diagnosis[1,2].Herein,we report on a macrocystic serous cystadenoma of the pancreas in a 46-year-old female patient,with a preoperative diagnosis of pancreatic pseudocyst by radiologic imaging.

关键词： pancreas adenoma diagnosis

Meso-Archean to Mid-Paleozoic Granitoids in Oulad Dlim Massif(the Pericratonic Terrane of the Reguibat Shield,West African Craton,Morocco):Petrology,Geochemistry,Geochronology and Geological Implications

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Journal of Earth Science 2022年第5期33卷 1152-1165页

作者： Haissen Faouziya Montero Pilar Molina Jose francisco Lodeiro francisco Mouttaqi Abdellah Chaib Mustapha Bea Fernando LGAGE Département de GéologieFacultédes Sciences Ben M’sikHassan II University of CasablancaB.P.5366MaarifCasablancaMaroc Department of Mineralogy and Petrology University of GranadaCampus FuentenuevaGranada18002Spain Office National des Hydrocarbures et des Mines 5 Avenue Moulay HassanRabatMaroc

The Oulad Dlim Massif,adjacent to the Reguibat Shield in South Morocco was considered up to now as part of the Variscan belt(Mauritanides)with a polyphase geologic history and a complex geodynamic evolution implicating oceans closures and accretion of exotic terranes(Avalonian and Meguman)during the Variscan-Alleghanian *** use of modern technology to characterize the petrology,the geochemistry and the geochronology of the lithological units forming this region,combined to field surveys has led to an updated geological architecture and different geological *** Oulad Dlim Massif is mainly a deformed Archean terrane,as recorded by its eastern and western sectors,dominated in its central part by a bimodal felsic-mafic magmatism forming the Ediacaran *** study of these magmatic complexes supports strongly the intracontinental origin of this bimodal magmatism *** oceanic origin published before in *** exploration of this massif conducted also to the identification of a Silurian-Devonian sector in the western ***,up to date,different magmatic events lasting from the Meso-Archean to the Cretaceous are recorded in the Oulad Dlim Massif rocks,among them different generations of granitoids are *** data on granitoids from the Ediacaran sector are presented in this *** recent data demonstrates that Oulad Dlim Massif has been affected by the main Ediacaran–Cambrian extensional event widely documented in other structural domains of Morocco and other parts of North ***,the study of the Silurian-Devonian sector rocks highlighted the presence of a Caledonian tectonic event challenging the ideas about the paleogeography of this part of northwestern Africa and its geological evolution during the ***,despite the significant contribution of this extensive survey and the abundance of data on the Oulad Dlim Massif,more studies are required to reconstruct the puzzle at plate tectonic scale.

关键词： Archean Ediacaran bimodal magmatism extension intracontinental rifting Caledonian tectonic event petrology geochemistry

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： francisco E Jorge José R da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

Endoscopic resection of an ampullary carcinoid presenting with upper gastrointestinal bleeding:A case report and review of the literature

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World Journal of Gastroenterology 2007年第8期13卷 1268-1270页

作者： Nooman Gilani francisco C Ramirez Carl. T. Hayden Veterans Administration Medical Center Phoenix AZ United States

Ampullary carcinoid is a rare tumor that can present with gastrointestinal bleeding, obstructive jaundice or pancreatitis. Some of these tumors are associated with Von Recklinghausen disease. The usual surgical options are a biliary-enteric anastomosis, Whipple procedure or rarely a local resection. The mean survival dqes not appear to be much different after a pancreaticoduodenectomy versus local surgical excision. We report a very rare case of a non-metastatic ampullary carcinoid causing upper gastrointestinal bleeding, which was managed by endoscopic ampullectomy.

关键词： Carcinoid Ampulla of Vater Ampullary tumor Ampullectomy Gastrointestinal bleeding

Real Renormings on Complex Banach Spaces

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Chinese Annals of Mathematics,Series B 2008年第3期29卷 239-246页

作者： francisco J GARC■A-PACHECO Alejandro MIRALLES Department of Mathematical Sciences Kent State University Departamento de Análisis Matemático Universidad de Valencia

The authors prove that every complex Banach space admits an equivalent real norm that is far away from being a complex norm. Furthermore, this real norm can be chosen to share many properties with complex norms, but i... 详细信息

关键词： Complex norms Real norms Hilbert space