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Submegahertz spectral width photon pair source based on fused silica microspheres

Photonics Research 2021年第11期9卷 2237-2252页

作者： ERASTO ORTIZ-RICARDO CESAR BERTONI-OCAMPO MONICA MALDONADO-TERRON ARTURO GARCIA ZURITA roberto ramirez-alarcon HECTOR CRUZ ramirez R.CASTRO-BELTRAN ALFRED B.U’REN Instituto de Ciencias Nucleares Universidad Nacional Autonoma de MexicoApartado Postal 70-54304510 MexicoD.F.Mexico Centro de Investigaciones en Optica A.C. Loma del Bosque 115Colonia Lomas del Campestre37150 LeonGuanajuatoMexico Departamento de Ingenieria Fisica Cuerpo Academico de Mecanica EstadisticaDivison de Ciencias e IngenieriasUniversidad de Guanajuato37150 LeonGuanajuatoMexico

High-efficiency submegahertz bandwidth photon pair generators will enable the field of quantum technology to transition from laboratory demonstrations to transformational applications involving information transfer from photons to *** spontaneous parametric processes are able to achieve high-efficiency photon pair generation,the spectral bandwidth tends to be relatively large,as defined by phase-matching *** solve this fundamental limitation,we use an ultrahigh quality factor(Q)fused silica microsphere resonant cavity to form a photon pair *** present the full theory for the spontaneous four-wave mixing(SFWM)process in these devices,fully taking into account all relevant source characteristics in our *** exceptionally narrow(down to kilohertz-scale)linewidths of these devices result in a reduction in the bandwidth of the photon pair generation,allowing submegahertz spectral bandwidth to be ***,using a pump source centered around 1550 nm,photon pairs with the signal and idler modes at wavelengths close to 1540 and 1560 nm,respectively,are *** herald a single idler-mode photon by detecting the corresponding signal photon,filtered via transmission through a wavelength division multiplexing channel of *** demonstrate the extraction of the spectral profile of a single peak in the single-photon frequency comb from a measurement of the signal–idler time of emission *** improvements in device design and experimental methods enabled the narrowest spectral width(Δν=366 k Hz)to date in a heralded single-photon source based on SFWM.

关键词： fused silica spectral

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Interleukin 1βreceptor and synaptic dysfunction in recurrent brain infection with Herpes simplex virus type-1

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Neural Regeneration Research 2025年第2期20卷 416-423页

作者： roberto Piacentini Claudio Grassi Department of Neuroscience UniversitàCattolica del Sacro CuoreRomeItaly Fondazione Policlinico Universitario A.Gemelli IRCCSRomeItaly

Several experimental evidence suggests a link between brain Herpes simplex virus type-1 infection and the occurrence of Alzheimer’s ***,the molecular mechanisms underlying this association are not completely *** the molecular mediators of synaptic and cognitive dysfunction occurring after Herpes simplex virus type-1 infection and reactivation in the brain neuroinflammatory cytokines seem to occupy a central ***,we specifically reviewed literature reports dealing with the impact of neuroinflammation on synaptic dysfunction observed after recurrent Herpes simplex virus type-1 reactivation in the brain,highlighting the role of interleukins and,in particular,interleukin 1βas a possible target against Herpes simplex virus type-1-induced neuronal dysfunctions.

关键词： herpes simplex virus type 1 interleukin 1β microglia neuroinflammation synaptic dysfunction

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Syndecans in Alzheimer's disease:pathogenetic mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第9期20卷 2594-2595页

作者： Carmela Rita Balistreri roberto Monastero Cellular Molecular and Clinical Pathological LaboratoryDepartment of BiomedicineNeuroscience and Advanced Diagnostics(Bi.N.D.)University of PalermoPalermoItaly Memory and Parkinson’s disease Center Policlinico“Paolo Giaccone”PalermoDepartment of BiomedicineNeuroscience and Advanced Diagnostics(Bi.N.D.)University of PalermoVia La Loggia 1PalermoItaly

With increasing age,humans become more susceptible to the onset of neurodegenerative diseases(NDs),and among these,Alzheimer's disease(AD)is the most frequent(Nicoletti et al.,2023).NDs are primarily characterized by neuronal loss and atrophy,but also by lesions involving the cerebral and/or cardiovascular system(Balistreri,2021).Lesions such as macroinfa rcts,microinfarcts,hemorrhages,white matter lesions,atherosclerosis,and arteriolosclerosis have also been significantly described in the preclinical stages of cognitive impairment characterizing NDs(Mariani et al.,2007).

关键词： Alzheimer cardiovascular

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Therapeutic targeting of cellular prion protein: toward the development of dual mechanism anti-prion compounds

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Neural Regeneration Research 2025年第4期20卷 1009-1014页

作者： Antonio Masone Chiara Zucchelli Enrico Caruso Giovanna Musco roberto Chiesa Laboratory of Prion Neurobiology Department of NeuroscienceIstituto di Ricerche Farmacologiche Mario Negri IRCCSMilanItaly Biomolecular NMR Unit Division of Genetics and Cell BiologyIRCCS Ospedale San RaffaeleMilanItaly Department of Biotechnology and Life Sciences University of InsubriaVareseItaly

PrPSc,a misfolded,aggregation-prone isoform of the cellular prion protein(PrPC),is the infectious prion agent responsible for fatal neurodegenerative diseases of humans and other *** adopt different pathogenic conformations(prion strains),which can be resistant to potential drugs,or acquire drug resistance,posing challenges for the development of effective *** PrPCis the obligate precursor of any prion strain and serves as the mediator of prion neurotoxicity,it represents an attractive therapeutic target fo r prion *** this minireview,we briefly outline the approaches to target PrPCand discuss our recent identification of Zn(Ⅱ)-Bn PyP,a PrPC-targeting porphyrin with an unprecedented bimodal mechanism of *** argue that in-depth understanding of the molecular mechanism by which Zn(Ⅱ)-Bn PyP targets PrPCmay lead toward the development of a new class of dual mechanism anti-prion compounds.

关键词： anti-prion drug anti-PrPC antibody antisense oligonucleotide neurodegeneration pharmacological chaperone porphyrin prion disease PrPC degrader PrPC shedding zinc finger repressor

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Improved frost forecast using machine learning methods

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Artificial Intelligence in Geosciences 2023年第1期4卷 164-181页

作者： Jos´e roberto Rozante Enver ramirez Diego ramirez Gabriela Rozante Center for Weather Forecast and Climate Studies National Institute for Space ResearchCachoeira PaulistaSPBrazil University of Sao Paulo(EEL/USP) LorenaSPBrazil Sao Paulo State University(UNESP) BauruSPBrazil

Frosts are one of the atmospheric phenomena with one of the larger negative effects on the agricultural sector in the southern region of Brazil,therefore,an earlier forecast can minimize their *** the present work,artificial neural networks(ANNs)techniques were applied in order to improve the predicting capabilities of frost events in southern *** the study,two multilayer perceptron(MLP)ANNs were built,one with ADAM optimizer and the other with *** input parameters MLP-ANNs were numerical predictions of the Eta *** ANNs were trained using four years(2012-2015),while validation and testing were performed using 2016 and 2017,*** episode of frost that occurred on May 21st,2018,related to an intense cold air mass,was also utilized to evaluate the performance of the *** best configurations(topologies and hyperparameters)of the ANNs were identified through experiments,using the highest accuracy obtained during the validation period as a *** results of the ANNs with ADAM and SGD optimizers were compared with the predictions of the Eta *** the case study,an additional comparison against the operational frost index(IG)from the National Institute for Space Research(INPE)was also *** performance of both ANNs(properly configured)with ADAM and SGD optimizers are comparable one to the *** both are significantly better compared to the Eta *** ANNs were able to drastically reduce the underestimation trends of frost events caused by the warm bias of the Eta *** ANNs also indicated more satisfactory performances when compared to the INPE *** general,the ANNs were able to identify deficiencies in Eta predictions,and consequently improve their *** this sense,the use of ANNs to predict frost events can be a very useful tool in an operational environment.

关键词： Frost Artificial neural networks Multilayer perceptron frost index Deep learning

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Rebound of Region of Interest (RROI), a New Kernel-Based Algorithm for Video Object Tracking Applications

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Journal of Signal and Information Processing 2014年第4期5卷 97-103页

作者： Andres alarcon ramirez Mohamed Chouikha Department of Electrical and Computer Engineering Howard University Washington DC USA

This paper presents a new kernel-based algorithm for video object tracking called rebound of region of interest (RROI). The novel algorithm uses a rectangle-shaped section as region of interest (ROI) to represent and track specific objects in videos. The proposed algorithm is constituted by two stages. The first stage seeks to determine the direction of the object’s motion by analyzing the changing regions around the object being tracked between two consecutive frames. Once the direction of the object’s motion has been predicted, it is initialized an iterative process that seeks to minimize a function of dissimilarity in order to find the location of the object being tracked in the next frame. The main advantage of the proposed algorithm is that, unlike existing kernel-based methods, it is immune to highly cluttered conditions. The results obtained by the proposed algorithm show that the tracking process was successfully carried out for a set of color videos with different challenging conditions such as occlusion, illumination changes, cluttered conditions, and object scale changes.

关键词： Video Object Tracking Cluttered Conditions Kernel-Based Algorithm

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From flatness, GPI observers, GPI control and flat filters to observer-based ADRC

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Control Theory and Technology 2018年第4期16卷 249-260页

作者： Hebertt SIRA-ramirez CINVESTAV-IPN Department of Electrical Engineering Mechatronics Section Avenida IPN No. 2508 Col. San Pedro Zacatenco CP 07360 CDMX Mexico

In this article, we establish the route taken by the author, and his research group, to bring differential flatness to the realm of active disturbance rejection control （ADRC）. This avenue entitled： 1） generalized proportional integral observers （GPIO）, as natural state and disturbance observers for fiat systems, 2） generalized proportional integral （GPI） control, provided with extra integrations, to produce a modular controller known as flat filters （FF＇s） and, finally, 3） the establishing of an equivalence of observer based ADRC with FF＇s. The context is that of pure integration systems. The obtained controllers depend only on the order of the flat system and they are to be directly used on the basis of the available flat output signal in a universal, modular, fashion. The map is complemented with the relevant references where the intermediate techniques were illustrated and developed, over the years, in connection with laboratory experimental implementations.

关键词： Flatness GPI observers GPI control reduced order GPI observers fiat filters

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On the role of the uncertainty principle in superconductivity and superfluidity

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Chinese Physics B 2012年第7期21卷 125-131页

作者： roberto Onofrio Dipartimento di Fisica e Astronomia"Galileo Galilei" Universitàdi PadovaVia Marzolo 8Padova 35131Italy ITAMP Harvard-Smithsonian Center for Astrophysics60 Garden StreetCambridgeMA 02138USA

We discuss the general interplay between the uncertainty principle and the onset of dissipationless transport phenomena such as superconductivity and superfluidity. We argue that these phenomena are possible because of the robustness of many-body quantum states with respect to the external environment, which is directly related to the uncertainty principle as applied to coordinates and momenta of the carriers. In the case of superconductors, this implies relationships between macroscopic quantities such as critical temperature and critical magnetic field, and microscopic quantities such as the amount of spatial squeezing of a Cooper pair and its correlation time. In the case of ultracold atomic Fermi gases, this should be paralleled by a connection between the critical temperature for the onset of superfluidity and the corresponding critical velocity. Tests of this conjecture are finally sketched with particular regard to the understanding of the behaviour of superconductors under external pressures or mesoscopic superconductors, and the possibility to mimic these effects in ultracold atomic Fermi gases using Feshbach resonances and atomic squeezed states.

关键词： superconductivity superfluidity uncertainty principle squeezed states

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Cough induced syncope:A hint to cardiac tamponade diagnosis

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World Journal of Cardiology 2017年第5期9卷 466-469页

作者： roberto ramirez Glenmore Lasam Department of Medicine Atlantic Health System-Overlook Medical CenterSummitNJ 07901United States

We report a case of a 75-year-old male with history oflung adenocarcinoma who presented with shortness of breath and frequent episodes of cough-induced syncope. A large pericardial effusion was found on echocardiogram suggestive of cardiac tamponade. Pericardiocentesis was done which improved the dyspnea and eventually resolved the syncope. There are only two other cases reported in the literature with cough-induced syncope in the setting of pericardial effusion or cardiac tamponade. Our clinical vignette also highlights the importance of pulsus paradoxus identification in patients with cough induced syncope to rule out cardiac tamponade since this is the most sensitive physical finding for its diagnosis.

关键词： Cardiac tamponade Cough-induced syncope Pericardial effusion

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Air Pollution, Government Pollution Regulation, and Industrial Production in China

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Journal of Systems Science & Complexity 2020年第4期33卷 1064-1079页

作者： CAO Dong ramirez Carlos D. School of Economics and Management Xidian UniversityXi’an 710071China Department of Economics George Mason UniversityFairfaxVAUnited States

Over the last four decades,a severe deterioration in air quality has accompanied China’s rapid *** a result,the Chinese government has implemented stricter policies and regulation to control air *** this paper,the authors create a measure of government policies on air pollution by tracking all pollution-related government announcements in Chinese *** authors then use this variable,along with measures of actual pollution,to investigate how air pollution,industrial production,and government policies on air pollution are *** authors conduct this investigation nationwide,as well as in five large cities in China.A vector autoregression model suggests that,nationwide,government policies seem to decrease air pollution without significantly affecting industrial ***,the effect appears to be short-lived,dissipating after a few *** addition,the authors find that the dynamic relationship among these variables differs by *** instance,following an adverse air quality shock in Beijing,government efforts to control pollution seem to have an ameliorating city-wide effect,decreasing local air pollution in subsequent *** Shanghai and Guangzhou,while the local government reacts to adverse air pollution shocks,the ameliorating effects are not statistically *** Chengdu and Shenyang,the authors detect no significant local government reaction to adverse air pollution ***,in these cities,local government policies do not impart a statistically measurable effect on air pollution.

关键词： pollution. pollution nationwide

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