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Secular dynamics of navigation satellites in the MEO and GSO regions

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Astrodynamics 2022年第4期6卷 357-374页

作者： Hanlun Lei emiliano ortore Christian Circi School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education Nanjing UniversityNanjing 210023China Department of Astronautical Electrical and Energy EngineeringSapienza University of RomeVia Salaria 851Rome 00138Italy

In this study,a dynamical model is developed to describe the secular evolution of navigation satellites under the geocentric reference frame with the Laplace orbit as the fundamental plane.The disturbing function,involving the effects of Earth's oblateness and lunisolar gravitational attraction,is averaged over the orbital periods of both the satellite and the perturbers.In the regions of medium-Earth orbits and geosynchronous orbits,there are varieties of lunisolar resonances for governing the secular dynamics of navigation satellites.Among these resonances,we are interested in the ones occurring at the critical inclinations as well as the lunar node resonances.For each resonance of interest,the resonant center and width are identified analytically.Finally,dynamical maps are compared with the analytical results.

关键词： secular resonances Laplace plane navigation satellites dynamical maps

Probe lifetime around natural satellites with obliquity

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Astrodynamics 2022年第4期6卷 429-439页

作者： Marco Cinelli Hanlun Lei emiliano ortore Christian Circi Istituto di Astrofisica e Planetologia Spaziali(IAPS) Istituto Nazionale di Astrofisica(INAF)Roma 00133Italy School of Astronomy and Space Science and Key Laboratory of Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing 210046China School of Aerospace Engineering Sapienza University of RomeRome 00138Italy Department of Astronautical Electricaland Energy EngineeringSapienza University of RomeRome 00138Italy

The dynamics of a probe orbiting a moon can be significantly influenced by the non-coincidence between the moon's equatorial and orbital planes.Thus,we performed a general analysis about the effects of the angle(obliquity)between the above-mentioned planes and of the angle(nodal phasing)between the nodal lines of the mother planet's apparent orbit and the probe orbit on the lifetime of the probe.The lifetime,strictly correlated to the variations in eccentricity of the probe orbit,was evaluated starting from low values of the semi-major axis,moderate eccentricity,and high inclination to offer high ground spatial resolution and extend latitudinal coverage of the natural satellite.This investigation,carried out through numerical simulations,may be useful for identifying the optimal initial conditions of the probe's orbit elements,leading to an important increase in the probe lifetime in missions devoted to the exploration of natural satellites.

关键词： third-body effect natural satellite probe lifetime

Geometrical approach for an optimal inter-satellite visibility

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Astrodynamics 2021年第3期5卷 237-248页

作者： Marco Cinelli emiliano ortore Giovanni Laneve Christian Circi Department of Mathematics University of Rome Tor VergataRome 00133Italy Department of Astronautical Electrical and Energy EngineeringSapienza University of RomeRome 00138Italy Scuola di Ingegneria Aerospaziale Sapienza University of RomeRome 00138Italy

In the eld of satellite constellations,an important requirement is often represented by the possibility to exchange data among the satellites or exploit mutual visibility to carry out measurements on the parameters of the Earth's atmosphere.Therefore,recursive and routing algorithms are usually implemented to evaluate inter-satellite visibility intervals.However,to design the con guration of the constellation,it is important to consider the orbital conditions that guarantee the mutual visibility between couples of satellites.Thus,in this study,a geometric analysis was performed to identify the optimal inter-satellite visibility conditions,expressed in terms of the di erence in the true anomaly between satellites characterized by di erent orbital con gurations.This approach allows a handy constellation design,without performing a numerical analysis.It is particularly useful in the case of a high number of satellites,when numerical techniques require signi cant computational e ort.Therefore,it is possible to considerably simplify the design of a constellation in which the mutual visibility between couples of satellites is always guaranteed.This type of constellation,usually referred to as satellite chain,can be exploited in several network services and remote sensing systems devoted to enhancing the knowledge of atmospheric parameters.

关键词： satellite constellation interlink visibility

Electricity as an Energy Vector: A Performance Comparison with Hydrogen and Biodiesel in Italy

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Open Journal of Energy Efficiency 2024年第1期13卷 1-24页

作者： emiliano Finocchi LUISS Business School Universit&#224 LUISS Guido Carli Rome Italy

This study presents a comparative analysis of electricity, hydrogen, and biodiesel as energy vectors, with a focus on powering an aluminum smelter in southern Italy. It evaluates these vectors in terms of efficiency, land requirements for carbon-neutral energy production, and capital expenditure, providing insights throughout the entire supply chain (upstream, midstream, and downstream) into their feasibility for industrial applications. The research reveals that biodiesel, despite being carbon neutral, is impractical due to extensive land requirements and lower efficiency if compared to other vectors. Hydrogen, downstream explored in two forms as thermal power generation and fuel cell technology, shows lower efficiency and higher capital expenditure compared to electricity. Additionally, green hydrogen production’s land requirements significantly exceed those of electricity-based systems. Electricity emerges as the most viable option, offering an overall higher efficiency, lower land requirements for its green production, and comparatively lower capital expenditure. The study’s findings highlight the importance of a holistic assessment of energy vectors, considering economic, environmental, and practical aspects along the entire energy supply chain, especially in industrial applications where the balance of these factors is crucial for long-term sustainability and feasibility. This comprehensive analysis provides valuable guidance for similar industrial applications, emphasizing the need for a balanced approach in the selection of energy vectors.

关键词： Electrification Hydrogen Energy Efficiency Renewables Decarbonization Electricity

Complications Associated with Autologous Fat Transfer: Case Report and Literature Review

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Modern Plastic Surgery 2024年第1期14卷 1-8页

作者： Bryan Armando Morales Eslava Carlos emiliano García Cordova Antoine Arturo Lagunes Gasca Department of Surgery Hospital Regional Petróleos Mexicanos Villahermosa Tabasco Mexico Department of Surgery Hospital Central Sur Petróleos Mexicanos Mexico City Mexico

Undoubtedly, since its appearance, the interest and use of autologous fat transfer (AFT) as a breast reconstruction technique have been increasing, becoming one of the main surgical alternatives for aesthetic breast augmentation. This increase in its popularity has led to the development of new technologies to increase its efficacy and safety, however, it has inherently implied the inadequate use of this procedure, mainly when performed by unqualified medical personnel. We present the case of a patient with complications following a breast AFT for aesthetic purposes, performed by a general practitioner without a specialty in plastic and reconstructive surgery.

关键词： Breast Breast Reconstruction Breast Surgery Autologous Fat Transfer Intramammary Abscess

Long-noncoding RNAs as epigenetic regulators in neurodegenerative diseases

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Neural Regeneration Research 2023年第6期18卷 1243-1248页

作者： Paola Ruffo Francesca De Amicis emiliano Giardina Francesca Luisa Conforti Medical Genetics Laboratory Department of PharmacyHealth and Nutritional SciencesUniversity of CalabriaRendeItaly Department of Pharmacy Health and Nutritional SciencesUniversity of CalabriaRendeItaly Genomic Medicine Laboratory UILDM IRCCS Fondazione Santa LuciaRomeItaly Department of Biomedicine&Prevention Tor Vergata University of RomeRomeItaly

The growing and rapid development of high-throughput sequencing technologies have allowed a greater understanding of the mechanisms underlying gene expression regulation.Editing the epigenome and epitranscriptome directs the fate of the transcript influencing the functional outcome of each mRNA.In this context,non-coding RNAs play a decisive role in addressing the expression regulation at the gene and chromosomal levels.Long-noncoding RNAs,consisting of more than 200 nucleotides,have been shown to act as epigenetic regulators in several key molecular processes involving neurodegenerative disorders,such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis and Huntington’s disease.Long-noncoding RNAs are abundantly expressed in the central nervous system,suggesting that their deregulation could trigger neuronal degeneration through RNA modifications.The evaluation of their diagnostic significance and therapeutic potential could lead to new treatments for these diseases for which there is no cure.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis epigenetic mechanism Huntington’s disease long-noncoding RNAs neurodegenerative disease non-coding RNAs Parkinson’s disease

Comprehensive lumped parameter and multibody approach for the dynamic simulation of agricultural tractors with tyre–soil interaction

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IET Cyber-Systems and Robotics 2023年第3期5卷 1-23页

作者： Massimo Martelli Damiano Chiarabelli Silvia Gessi Pietro Marani emiliano Mucchi Marco Polastri Institute of Sciences and Technologies for Sustainable Energy and Mobility CNR‐STEMSNational Research CouncilFerraraItaly Department of Engineering University of FerraraFerraraItaly

Modern agricultural tractors are complex systems,in which multiple physical(and technological)domains interact to reach a wide set of competing goals,including work operational performance and energy efficiency.This complexity translates to the dynamic,multi‐domain simulation models implemented to serve as digital twins,for rapid prototyping and effective pre‐tuning,prior to bench and on‐field testing.Consequently,a suitable simulation framework should have the capability to focus both on the vehicle as a whole and on individual subsystems.For each of the latter,multiple options should be available,with different levels of detail,to properly address the relevant phenomena,depending on the specific focus,for an optimal balance between accuracy and computation time.The methodology proposed here by the authors is based on the lumped parameter approach and integrates the models for the following subsystems in a modular context:internal combustion engine,hydromechanical transmission,vehicle body,and tyre–soil interaction.The model is completed by a load cycle module that generates stimulus time histories to reproduce the work load under real operating conditions.Traction capability is affected by vertical load on the wheels,which is even more relevant if the vehicle is travelling on an uncompacted soil and subject to a variable drawbar pull force as it is when ploughing.The vertical load is,in turn,heavily affected by vehicle dynamics,which can be accurately modelled via a full multibody implementation.The presented lumped parameter model is intended as a powerful simulation tool to evaluate tractor performance,both in terms of fuel consumption and traction dynamics,by considering the cascade phenomena from the wheel–ground interaction to the engine,passing through the dynamics of vehicle bodies and their mass transfer.Its capabilities and numerical results are presented for the simulation of a realistic ploughing operation.

关键词： agricultural tractor digital twin lumped parameter simulation,multibody powertrain tyre-soil interaction

Emerging vaccine nanotechnology: From defense against infection to sniping cancer

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Acta Pharmaceutica Sinica B 2022年第5期12卷 2206-2223页

作者： Chan Feng Yongjiang Li Bijan emiliano Ferdows Dylan Neal Patel Jiang Ouyang Zhongmin Tang Na Kong Enguo Chen Wei Tao Department of Respiratory Medicine Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China Center for Nanomedicine and Department of Anesthesiology Brigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115USA Cancer Center Zhejiang UniversityHangzhou 310058China Department of Pharmacy the Second Xiangya Hospital of Central South UniversityChangsha 410011China

Looking retrospectively at the development of humanity, vaccination is an unprecedented medical landmark that saves lives by harnessing the human immune system. During the ongoing coronavirus disease 2019(COVID-19) pandemic, vaccination is still the most effective defense modality. The successful clinical application of the lipid nanoparticle-based Pfizer/BioNTech and Moderna mRNA COVID-19 vaccines highlights promising future of nanotechnology in vaccine development. Compared with conventional vaccines, nanovaccines are supposed to have advantages in lymph node accumulation,antigen assembly, and antigen presentation;they also have, unique pathogen biomimicry properties because of well-organized combination of multiple immune factors. Beyond infectious diseases, vaccine nanotechnology also exhibits considerable potential for cancer treatment. The ultimate goal of cancer vaccines is to fully mobilize the potency of the immune system as a living therapeutic to recognize tumor antigens and eliminate tumor cells, and nanotechnologies have the requisite properties to realize this goal.In this review, we summarize the recent advances in vaccine nanotechnology from infectious disease prevention to cancer immunotherapy and highlight the different types of materials, mechanisms, administration methods, as well as future perspectives.

关键词： Vaccine Nanotechnology Infection Cancer Nanovaccines Vaccination Diseases prevention Immunotherapy

Low-cost Free-standing ferroelectric polymer films with high polarization produced via pressing-and-folding

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Journal of Materiomics 2022年第3期8卷 640-648页

作者： Nan Meng Xintong Ren Jiyue Wu emiliano Bilotti Michael J.Reece Haixue Yan State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondonE14NSUK Department of Materials Science and State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai200433China

Ferroelectric polymer poly(vinylidene fluoride)(PVDF)shows excellent electro-activity and is promising for flexible electronic devices.However,the processing of PVDF into the favourable ferroelectric structure(β-phase)presents difficulties,while its copolymer with trifluoroethylene(PVDF-TrFE)can directly crystallize into β-phase,but shows limited thermal stability and high-cost processing.As a result,an easily implementable method,pressing-and-folding(P&F),was used to produce highly compatible blended films of PVDF and PVDF-TrFE without using any hazardous solvent or complex polymer processing equipment.Hot-pressed PVDF(molecular weight:530 kg/mol)and PVDF-TrFE(molar ratio:51/49)films were firstly stacked before undergoing P&F treatment.Compared to extrusion-blended films before and after P&F,the P&F stacked films showed isotropic crystalline structure of b-phase,as confirmed using X-ray diffraction and infrared spectroscopy.The ferroelectric remnant polarization of the P&F stacked films is 0.068 C/m^(2),surpassing pure PVDF-TrFE(0.062 C/m^(2))and the simulated value of remnant polarization of pure PVDF(~0.065 C/m^(2)).The above findings promise to provide inspirations for new processing strategy on PVDF-based functional polymers.

关键词： Polymer blends PVDF PVDF-TrFE Ferroelectric Polarization