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comment on “constraining the smoothness parameter and dark energy using observational H(z) data”

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Research in Astronomy and Astrophysics 2011年第6期11卷 637-640页

作者： v.c.Busti R.c.santos Instituto de Astronomia Geofísica e Ciências AtmosféricasUniversidade de So PauloSo Paulo05508-090 SPBrazil Departamento de ciê ncias Exatas e da Terra Universidade Federal de So Paulo(UNIFESP)Diadema09972-270 SPBrazil

We discuss a recent analysis by Yu et al.[RAA 11,125（2011）] about constraints on the smoothness parameter α and dark energy models using observational H（z） *** is argued here that their procedure is conceptually inconsistent with the basic assumptions underlying the adopted Dyer-Roeder *** order to properly quantify the influence of the H（z） data on the smoothness parameter α,a χ2-test involving a sample of type Ia supernovae and H（z） data in the context of a flat ΛcDM model is *** result is confronted with an earlier approach discussed by santos et al.（2008） without H（z） *** the（Ωm,α） plane,it is found that such parameters are now restricted to be in the intervals 0.66 ≤ α ≤ 1.0 and 0.27 ≤ Ωm ≤ 0.37 within the 95.4 confidence level（2σ）,and,therefore,are fully compatible with the homogeneous *** basic conclusion is that a joint analysis involving H（z） data can indirectly improve our knowledge about the influence of the ***,this happens only because the H（z） data provide tighter constraints on the matter density parameter Ωm.

关键词： cosmology — dark energy — cosmological parameters

Modeling neutral-atmospheric electromagnetic delays in a“big data”world

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Geo-Spatial Information Science 2018年第2期21卷 75-79页

作者： Marcelo c.santos Thalia Nikolaidou Department of Geodesy and Geomatics Engineering University of New BrunswickFrederictonCanada

If left unmodeled,the delay suffered by electromagnetic waves while crossing the neutral atmosphere negatively affects Global Navigation Satellite System *** modeling of the delay has been carried out by means of empirical models formulated based on climatological information or using information extracted from numerical weather prediction(NWP)*** paper explores the potential use of meteorological information of several types that will become available with the increasing number of sensors(e.g.a cell phone,or the thermometer of a nearby smart home)in *** can we make use of these potentially huge datasets,which may help to provide the best possible representation of the neutral atmosphere at any given time,as readily and as accurately as possible?This situation falls in the realm of Big Data.A few potential scenarios,a sequential improvement of Marini mapping function coefficients,a self-feeding NWP,and near real-time empirical model updates,are discussed in this *** pros and cons of each approach are discussed in comparison with what is done *** indicate that they have potential for a positive contribution.

关键词： Global navigation satellite system(GNSS) big data neutral atmosphere

capacitorless Solid-state Power Filter for Single-phase Dc-Ac converters

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cES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli c.Dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(Lc)cell or an inductor-capacitor-inductor(LcL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the Lc filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

Nonlocal material properties of single-walled carbon nanotubes

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International Journal of Smart and Nano Materials 2012年第2期3卷 141-151页

作者： J.v.Araújo dos santos c.M.Mota Soares IDMEc Instituto Superior TécnicoUniversidade Técnica de Lisboa1049-001 LisboaPortugal

Natural frequencies of single-walled carbon nanotubes(SWcNTs)obtained using a model based on Eringen’s nonlocal continuum mechanics and the Timoshenko beam theory are compared with those obtained by molecular dynamics *** goal was to determine the values of the material constant,considered here as a nonlocal property,as a function of the length and the diameter of *** present approach has the advantage of eliminating the SWcNT thickness from the computations.A sensitivity analysis of natural frequencies to changes in the nonlocal material constant is also carried out and it shows that the influence of the nonlocal effects decreases with an increase in the SWcNT *** matching of natural frequencies shows that the nonlocal material constant varies with the natural frequency and the SWcNT length and diameter.

关键词： nonlocal mechanics molecular dynamics simulation single-walled carbon nanotube Timoshenko beam

MGMT and MLH1 methylation in Helicobacter pylori-infected children and adults

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World Journal of Gastroenterology 2013年第20期19卷 3043-3051页

作者： Marisa c Alvarez juliana c santos Nathália Maniezzo Marcelo S Ladeira Artur Lc da Silva Isabel cA Scaletsky José Pedrazzoli Jr Marcelo L Ribeiro Unidade Integrada de Farmacologia e Gastroenterologia Universidade So FranciscoBragan a Paulista 12916-900SPBrazil Programa de Pós Gradua o em Genética e Biologia Molecular State University of CampinasCampinas 13083-970SPBrazil Departamento de clínica Médica UNESPBotucatu 18618-970SPBrazil Departamento de Genética Universidade Federal do ParáBelém 68400-000PABrazil Departamento de Microbiologia Imunologia e ParasitologiaUniversidade Federal de So PauloSo Paulo 04021-001SPBrazil

AIM:To evaluate the association between Helicobacter pylori(***) infection and MLH1 and MGMT methylation and its relationship with microsatellite instability(MSI).METHODS:The methylation status of the MLH1 and MGMT promoter region was analysed by methylation specific methylation-polymerase chain reaction(MSPPcR) in gastric biopsy samples from uninfected or ***-infected children(n = 50),from adults with chronic gastritis(n = 97) and from adults with gastric cancer(n = 92).MLH1 and MGMT mRNA expression were measured by real-time PcR and normalised to a constitutive gene(β actin).MSI analysis was performed by screening MSI markers at 4 loci(Bat-25,Bat-26,D17S250 and D2S123) with PcR;PcR products were analysed by single strand conformation polymorphism followed by silver *** analyses were performed with either the χ 2 test with Yates continuity correction or Fisher's exact test,and statistical significance for expression analysis was assessed using an unpaired Student's ***:Methylation was not detected in the promoter regions of MLH1 and MGMT in gastric biopsy samples from children,regardless of *** infection *** MGMT promoter was methylated in 51% of chronic gastritis adult patients and was associated with *** infection(P c cancer patients,and the difference in the percentage of methylated samples between these patients and those from ***-infected chronic gastritis patients was statistically significant(P cies among ***-infected and non-infected chronic gastritis adult patients were 13% and 7%,*** observed methylation of the MLH1 promoter(39%) and increased MSI levels(68%) in samples from gastric cancer patients in comparison to samples from ***-infected adult chronic gastritis patients(P ctively).The frequency of promoter methylation for both genes was higher in gastric cancer sam

关键词： Helicobacter pylori Microsatellite instability Promoter methylation MLH1 MGMT Gastric cancer

Spouting behavior of binary particle mixtures of different densities: Fluid dynamics and particle segregation

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Particuology 2019年第1期17卷 58-66页

作者： K.G. santos R.c. Santana D.L. Souza v.v. Murata M.A.S. Barrozo Federal University ofTriangulo Mineiro Chemical Engineering DepartmentUniverdecidade CampusUberabaMGBrazil Federal University of Uberlandia Chemical Engineering SchoolUberlandiaMG. Brazil

Numerous industrial applications of spouted beds involve a mixture of granular particles, where differences in particle size, density, and shape can cause particle segregation, affecting the quality of flow and decreasing product homogeneity. The aim of this study was to investigate the particle segregation and fluid dynamics of a conical spouted bed operating with a binary mixture of particles of different densities. Using glass beads and polyethylene particles with a diameter of 4 mm, we determined the effects of the mass fraction of denser particles and static bed height on the minimum spouting condition and mixture index. The pressure drop and airflow in the minimum spouting condition increased with an increase in bed height or jetsam concentration. Regarding particle segregation, the jetsam particles tended to concentrate near the bottom, at the spout–annulus interface because they have a shorter trajectory than the lighter particles in the fountain region. Jetsam-rich mixtures with high initial static bed heights exhibited more efficient particle mixing, excluding those at the bottom of the bed.

关键词： Density Segregation Spouted bed Binary mixtures

MicroRNAs as potential diagnostic biomarkers for bipolar disorder

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Neural Regeneration Research 2025年第6期20卷 1681-1695页

作者： Bridget Martinez Philip v.Peplow Department of Pharmacology University of Nevada-RenoRenoNVUSA Department of Medicine University of Nevada-RenoRenoNVUSA Department of Anatomy University of OtagoDunedinNew Zealand

Abnormal expression of microRNAs is connected to brain development and disease and could provide novel biomarkers for the diagnosis and prognosis of bipolar disorder. We performed a PubMed search for microRNA biomarkers in bipolar disorder and found 18 original research articles on studies performed with human patients and published from January 2011 to June 2023. These studies included microRNA profiling in bloodand brain-based materials. From the studies that had validated the preliminary findings,potential candidate biomarkers for bipolar disorder in adults could be miR-140-3p,-30d-5p,-330-5p,-378a-5p,-21-3p,-330-3p,-345-5p in whole blood, miR-19b-3p,-1180-3p,-125a-5p, let-7e-5p in blood plasma, and miR-7-5p,-23b-5p,-142-3p,-221-5p,-370-3p in the blood serum. Two of the studies had investigated the changes in microRNA expression of patients with bipolar disorder receiving treatment. One showed a significant increase in plasma miR-134 compared to baseline after 4 weeks of treatment which included typical antipsychotics, atypical antipsychotics, and benzodiazepines. The other study had assessed the effects of prescribed medications which included neurotransmitter receptorsite binders(drug class B) and sedatives, hypnotics, anticonvulsants, and analgesics(drug class c) on microRNA results. The combined effects of the two drug classes increased the significance of the results for miR-219 and-29c with miR-30e-3p and-526b* acquiring significance. MicroRNAs were tested to see if they could serve as biomarkers of bipolar disorder at different clinical states of mania, depression, and euthymia. One study showed that upregulation in whole blood of miR-9-5p,-29a-3p,-106a-5p,-106b-5p,-107,-125a-3p,-125b-5p and of miR-107,-125a-3p occurred in manic and euthymic patients compared to controls, respectively, and that upregulation of miR-106a-5p,-107 was found for manic compared to euthymic patients. In two other studies using blood plasma,downregulation of miR-134 was observed i

关键词： biomarker bipolar disorder blood leukocytes blood plasma blood plasma extracellular vesicles/exosomes blood serum brain tissue brain tissue extracellular vesicles/exosomes lymphoblastoid cell lines microRNA neural progenitor cells whole blood

MicroRNAs as potential biomarkers for diagnosis of post-traumatic stress disorder

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Neural Regeneration Research 2025年第7期20卷 1957-1970页

Post-traumatic stress disorder is a mental disorder caused by exposure to severe traumatic life ***,there are no validated biomarkers or laboratory tests that can distinguish between trauma survivors with and without post-traumatic stress *** addition,the heterogeneity of clinical presentations of post-traumatic stress disorder and the overlap of symptoms with other conditions can lead to misdiagnosis and inappropriate *** suggests that this condition is a multisystem disorder that affects many biological systems,raising the possibility that peripheral markers of disease may be used to diagnose post-traumatic stress *** performed a PubMed search for microRNAs(miRNAs)in post-traumatic stress disorder(PTSD)that could serve as diagnostic biomarkers and found 18 original research articles on studies performed with human patients and published January 2012 to December *** included four studies with whole blood,seven with peripheral blood mononuclear cells,four with plasma extracellular vesicles/exosomes,and one with serum *** of these studies had also used whole *** studies were excluded as they did not involve microRNA *** of the studies had collected samples from adult male veterans who had returned from deployment and been exposed to combat,and only two were from recently traumatized adult *** measuring miRNA expression levels,many of the studies had used microarray miRNA analysis,miRNA Seq analysis,or NanoString *** six studies had used real time polymerase chain reaction assay to determine/validate miRNA expression in PTSD subjects compared to *** miRNAs that were found/validated in these studies may be considered as potential candidate biomarkers for PTSD and include miR-3130-5p in whole blood;miR-193a-5p,-7113-5p,-125a,-181c,and-671-5p in peripheral blood mononuclear cells;miR-10b-5p,-203a-3p,-4488,-502-3p,-874-3p,-5100,and-7641 in plasma extracellular vesicles/

关键词： biomarker diagnosis microRNA peripheral blood mononuclear cells plasma extracellular vesicles/exosomes post-traumatic stress disorder serum exosomes whole blood whole plasma

New insights into the hardening and pitting corrosion mechanisms of thermally aged duplex stainless steel at 475℃:A comparative study between 2205 and 2101 steels

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Journal of Materials Science & Technology 2022年第3期98卷 123-135页

作者： R.Silva G.S.vacchi c.L.Kugelmeier I.G.R.santos A.A.Mendes Filho D.c.c.Magalhães c.R.M.Afonso v.L.Sordi c.A.D.Rovere Munir Rachid corrosion Laboratory Department of Materials EngineeringFederal University of São CarlosRodovia Washington Luis Km 23513565-905 São CarlosSPBrazil Engineering Modeling and Applied Social Sciences Center(CECS)Federal University of ABCAvenida dos Estados 500109210580 Santo AndréSPBrazil Federal University of São carlos Graduate Program in Materials Science and EngineeringBrazil

In this study,the relationship between spinodal decomposition and the formation of Ni-rich clusters and G-phase in the ferrite on hardening and pitting corrosion of two thermally aged duplex stainless steels(DSSs)at 475℃was *** indicate that,for 2205 DSS,pitting corrosion behavior is influenced by the presence and size of G-phase precipitates for longer aging times,but this contribution is masked by the advanced stage of spinodal decomposition in the ferritic *** the other hand,for 2101 DSS,the formation of cr-richer nitrides impairs pitting corrosion resistance more than spinodal decomposition.

关键词： Duplex stainless steel Spinodal decomposition G-phase precipitation Pitting corrosion Hardening