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Relation between Mass and Radius of Exoplanets Distinguished by their Density

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作者： Davies miranda.

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Research in Astronomy and Astrophysics 2023年第6期23卷 47-55页

作者： Alberto S.Betzler Joség.V.miranda Centro de Ciência e Tecnologia em Energia e Sustentabilidade Universidade Federal do Recôncavo da BahiaFeira de SantanaBahia44.085-132Brazil Instituto de Fisica Universidade Federal da BahiaSalvadorBahia40.170-115Brazil

The formation of the solar system has been studied since the 18th century and received a boost in 1995 with the discovery of the first exoplanet,51 Pegasi *** investigations increased the number of confirmed planets to about5400 to *** possible internal structure and composition of these planets can be inferred from the relationship between planet mass and radius,*** have analyzed the M-R relation of a selected sample of iron-rock and ice-gas planets using a fractal approach to their *** application of fractal theory is particularly useful to define the physical meaning of the proportionality constant and the exponent in an empirical M-R power law in exoplanets,but this does not necessarily mean that they have an internal fractal *** M-R relations based on this sample are M=(1.46±0.08)R^(2.6±0.2)for the rocky population(3.6≤ρ≤14.3 g cm^(-3)),with 1.5≤M≤39M_(⊕),and M=(0.27±0.04)R^(2.7±0.2)for ice-gas planets(0.3≤ρ≤2.1 g cm^(-3))with 5.1≤M≤639 M_(⊕)(or■2 M_(J))and orbital periods greater than 10 *** M-R relations have in their density range a great predictive power for the determination of the mass of exoplanets and even for the largest icy moons of the solar *** average fractal dimension of these planets is D=2.6±0.1,indicating that these objects likely have a similar degree of heterogeneity in their densities and a nearly similar composition in each *** M-R diagram shows a"gap"between ice-gas and iron-rock *** gap is a direct consequence of the density range of these two *** empirically propose an upper mass limit of about 100 M_(⊕),so that an M-R relation for ice-gas planets in a narrow density range is defined by M∝R^(3).

关键词： planets and satellites:formation planets and satellites:terrestrial planets planets and satellites:gaseous planets

Eradication of Helicobacter pylori infection:Which regimen first?

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World Journal of gastroenterology 2014年第3期20卷 665-672页

作者： Alessandro Federico Antonietta gerarda gravina Agnese miranda Carmela Loguercio Marco Romano Department of Clinical and Experimental Medicine Gastroenterology UnitSecond University of Naples

Helicobacter pylori (H. pylori) is a well-known human pathogen that plays an essential role in the pathogenesis of chronic gastritis, peptic ulcer disease, and gastric malignancies. Although H. pylori is susceptible to several antimicrobials, this infection has proven challenging to cure because of the increasing prevalence of bacterial strains that are resistant to the most commonly used antimicrobials, particularly clarithromycin. An effective (i.e., > 90%) first-line therapy is mandatory for avoiding supplementary treatments and testing, and more importantly for preventing the development of secondary resistance. This study reviews the recent literature on first-line therapies for H. pylori. The eradication rates following standard triple therapy (a proton pump inhibitor plus amoxicillin and clarithromycin) for H. pylori infection are declining worldwide. Several first-line strategies have been proposed to increase the eradication rate, including extending the treatment duration to 14 d, the use of a four-drug regimen (bismuth-containing quadruple, sequential, and concomitant treatments), and the use of novel antibiotics, such as fluoroquinolones. However, the efficacy of these regimens is controversial. A first-line eradication regimen should be based on what works best in a defined geographical area and must take into account the prevalence of antimicrobial resistance in that region.

关键词： Helicobacter pylori Sequential therapy Hybrid therapy Concomitant therapy Clarithromycin Levofloxacin

The role of MDM2 and MDM4 in breast cancer development and prevention

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Journal of Molecular Cell Biology 2017年第1期9卷 53-61页

作者： Sue Haupt Reshma Vijayakumaran Panimaya Jeffreena miranda Andrew Burgess Elgene Lim Ygal Haup Tumour Suppression Laboratory Peter MacCallum Cancer Centre Melbourne 3000 Australia Sir Peter MacCallum Department of Oncology The University of Melbourne Melbourne 3000 Australia The Kinghorn Cancer Centre Garvan Institute of Medical Research Sydney New South Wales 2010 Australia St. Vincent's Clinical School Faculty of Medicine University of New South Wales Sydney New South Wales 2010 Australia Department of Pathology The University of Melbourne Parkville Victoria 3010 Australia Department of Biochemistry and Molecular Biology Monash University Clayton Australia

The major cause of death from breast cancer is not the primary turnout, but relapsing, drug-resistant, metastatic disease. Identifying factors that contribute to aggressive cancer offers important leads for therapy. Inherent defence against carcinogens depends on the individual molecular make-up of each person. Important molecular determinants of these responses are under the control of the mouse double minute （MDM） family： comprised of the proteins MDM2 and MDM4. In normal, healthy adult cells, the MDM family functions to critically regulate measured, cellular responses to stress and subsequent recovery. Proper function of the MDM family is vital for normal breast development, but also for preserving genomic fidelity. The MDM family members are best characterized for their negative regulation of the major tumour suppressor p53 to modulate stress responses. Their impact on other cellular regulators is emerging. Inappropriately elevated protein levels of the MDM family are highly associated with an increased risk of cancer incidence. Exploration of the MDM family members as cancer therapeutic targets is relerant for designing tailored anti-cancer treatments, but successful approaches must strategically consider the impact on both the target cancer and adjacent healthy ceils and tissues. This review focuses on recent findings pertaining to the role of the MDM family in normal and malignant breast cells.

关键词： MDM2 MDM4 TP53 p53 breast cancer

Unusual presentation of localized gingival enlargement associated with a slow-growing odontogenic myxoma

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International Journal of Oral Science 2013年第3期5卷 172-175页

作者： Jaume miranda Rius Alfons Nadal Eduard Lahor Beatus Mtui Llu 's Brunet Departament d’Odontostomatologia Facultat d’Odontologia Universitat de Barcelona Servei d’Anatomia Patològica Hospital Clinic Facultat de Medicina Universitat de Barcelona Dental & Oral Department Soweto General Hospital Arusha Servei d’Odontologia Hospital Universitari Sant Joan de Déu Universitat de Barcelona

Unusual presentation of localized gingival enlargement associated with a subjacent tumoural pathology is *** patient was a55-year-old black male,whose chief complaint was a progressive gingival overgrowth for more than ten years,in the buccal area of the anterior left *** to the clinical features and the radiological diagnosis of odontogenic keratocyst,a conservative surgery with enucleation and curettage was *** submitted for histopathological analysis rendered the diagnosis of odontogenic *** 12-month of follow-up,no evidence of recurrence was *** should be cautious when facing any gingival enlargement to avoid diagnostic pitfalls and to indicate the appropriate treatment.

关键词： gingival enlargement jaw neoplasm odontogenic tumour myxoma myxofibroma

Different kinds of stem cells in the development of SARS-CoV-2 treatments

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World Journal of Stem Cells 2021年第5期13卷 439-451页

作者： Monica Maribel Mata-miranda Miguel Sanchez-Brito gustavo Jesus Vazquez-Zapien Cell and Tissue Biology Laboratory Escuela Militar de MedicinaMexico 11200Mexico Computational Sciences TecNM/Technological Institute of AguascalientesAguascalientes 20256Mexico Embryology Laboratory Escuela Militar de MedicinaMexico 11200Mexico

On February 11,2020,the World Health Organization officially announced the coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),as an emerging recent pandemic illness,which currently has approximately taken the life of two million persons in more than 200 ***,clinical,and scientific efforts have focused on searching for new prevention and treatment *** medicine and tissue engineering focused on using stem cells(SCs)have become a promising tool,and the regenerative and immunoregulatory capabilities of mesenchymal SCs(MSCs)and their exosomes have been ***,it has been essential to establishing models to reproduce the viral life cycle and mimic the pathology of COVID-19 to understand the virus's *** fields of pluripotent SCs(PSCs),induced PSCs(iPSCs),and artificial iPSCs have been used for this purpose in the development of infection models or ***,some inconveniences have been declared in SC use;for example,it has been reported that SARS-CoV-2 enters human cells through the angiotensin-converting enzyme 2 receptor,which is highly expressed in MSCs,so it is important to continue investigating the employment of SCs in COVID-19,taking into consideration their advantages and *** this review,we expose the use of different kinds of SCs and their derivatives for studying the SARS-CoV-2 behavior and develop treatments to counter COVID-19.

关键词： COVID-19 SARS-CoV-2 Stem cells Exosomes Pluripotent stem cells Mesenchymal stem cells Artificial stem cells

Tritrichomonas foetus:New structures by high-resolution scanning helium ion microscopy

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BIOCELL 2021年第2期45卷 259-266页

作者： MARLENE BENCHIMOL ABIgAIL miranda-MAgALHÃES ANTONIO PEREIRA-NEVES WANDERLEY DE SOUZA Universidade do grande Rio Duque de Caxias25071-202Rio de Janeiro Departamento de Microbiologia Laboratório de Biologia Celular de PatógenosFiocruzInstituto Aggeu MagalhãesRecife52060-269Brazil Universidade Federal do Rio de Janeiro Instituto de Biofísica Carlos Chagas FilhoLaboratório de Ultraestrutura Celular Hertha Meyer Instituto Nacional de Ciência e Tecnologia(INBEB)and Centro Nacional de Biologia Estrutural e Bioimagens(CENABIO)Rio de Janeiro21941-902Brazil

Helium ion scanning microscopy(HIM)is a novel high-resolution scanning microscopy technique that uses helium ions instead of electrons to form images of the highest quality and resolution,providing a sub-nanometer resolution sputter uncoated biological ***,we took advantage of HIM to explore the cell surface of Tritrichomonas foetus,a protist parasite of cattle that provokes hard infection and abortion in *** describe thin protrusions,like nanotubes described in other cells,with different sizes(27 nm to 81 nm in thickness)and various lengths(from 73 nm to 2μm),as well bulbous structures either budding from the cell surface or present in the extremities of some *** flagella also presented these thin protrusions and different protein decoration,similar to those previously described using freeze-fracture *** between two cells were also seen,and their role in infection is *** cell surface was also examined and showed several pits indicative of endocytic activity and other types of arrays of *** observations were confirmed using Scanning Electron Microscopy(SEM),negative staining,and conventional thin sectioning for observation by transmission electron *** findings provide new and relevant information that may contribute to a better understanding of protozoan biology and its interaction with mammalian cells.

关键词： Nanotubes Microvesicles Surface specializations

Pressure drop analysis on the positive half-cell of a cerium redox flow battery using computational fluid dynamics: mathematical and modelling aspects of porous media

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Frontiers of Chemical Science and Engineering 2021年第2期15卷 399-409,F0004页

作者： Fernando F.Rivera Berenice miranda-Alcantara german Orozco Carlos Ponce de Leon Luis F.Arenas National Council of Science and Technology(CONACYT) Mexico City 03940Mexico Center of Research and Technological Development in Electrochemistry(CIDETEQ) Queretaro 76703Mexico Electrochemical Engineering Laboratory Energy Technology Research GroupFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthampton SO171BJUK

Description of electrolyte fluid dynamics in the electrode compartments by mathematical models can be a powerful tool in the development of redox flow batteries(RFBs)and other electrochemical *** order to determine their predictive capability,turbulent Reynolds-averaged Navier-Stokes(RANS)and free flow plus porous media(Brinkman)models were applied to compute local fluid velocities taking place in a rectangular channel electrochemical flow cell used as the positive half-cell of a cerium-based RFB for laboratory *** different platinized titanium electrodes were considered,a plate plus a turbulence promoter and an expanded metal *** pressure drop was validated against experimental data obtained with typical cerium *** was found that the pressure drop values were better described by the RANS approach,whereas the validity of Brinkman equations was strongly dependent on porosity and permeability values of the porous media.

关键词： CFD simulation porous media porous electrode pressure drop redox flow battery

Risk Models for the Prize Collecting Steiner Tree Problems with Interval Data

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 1-26页

作者： Eduardo lvarez-miranda Alfredo Candia-Vjar Xu-jin CHEN Xiao-dong HU Bi LI Industrial Management Department Universidad de TalcaChile DEI University of BolognaItaly Academy of Mathematics and Systems Science CAS

given a connected graph g=（V,E）with a nonnegative cost on each edge in E,a nonnegative prize at each vertex in V,and a target set V′V,the Prize Collecting Steiner Tree（PCST）problem is to find a tree T in g interconnecting all vertices of V′such that the total cost on edges in T minus the total prize at vertices in T is *** PCST problem appears frequently in practice of operations *** the problem is NP-hard in general,it is polynomial-time solvable when graphs g are restricted to series-parallel *** this paper,we study the PCST problem with interval costs and prizes,where edge e could be included in T by paying cost xe∈[c e,c＋e]while taking risk（c＋e xe）/（c＋e c e）of malfunction at e,and vertex v could be asked for giving a prize yv∈[p v,p＋v]for its inclusion in T while taking risk（yv p v）/（p＋v p v）of refusal by *** establish two risk models for the PCST problem with interval *** given budget upper bound on constructing tree T,one model aims at minimizing the maximum risk over edges and vertices in T and the other aims at minimizing the sum of risks over edges and vertices in *** propose strongly polynomial-time algorithms solving these problems on series-parallel graphs to *** study shows that the risk models proposed have advantages over the existing robust optimization model,which often yields NP-hard problems even if the original optimization problems are polynomial-time solvable.

关键词： uncertainty modeling prize collecting Steiner tree interval data series-parallel graphs polynomial-time solvability