检索结果-南通市图书馆

A virtual model of the retina based on histological data as a tool for evaluation of the visual fields

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Annals of Eye Science 2017年第1期2卷 113-126页

作者： Francisco-javier Carreras Ángel V.Delgado José.L.garc.a-Serrano Department of Surgery Medical School2Department of Applied PhysicsSchool of SciencesUniversity of GranadaGranadaSpain Hospital Clínico San Cecilio University of GranadaGranadaSpain School of Computer Science Department of Computer Science and Artificial IntelligenceUniversity of GranadaGranadaSpain

Background:To settle the fundamentals of a numerical procedure that relates retinal ganglion-cell density and threshold sensitivity in the visual *** sensitivity of a generated retina and visual pathways to virtual stimuli are simulated,and the conditions required to reproduce glaucoma-type defects both in the optic-nerve head(ONH)and visual fields are ***:A definition of selected structural elements of the optic pathways is a requisite to a translation of clinical knowledge to computer programs for visual field *** program is able to generate a database of normalized visual *** relationship between the number of extant receptive fields and threshold sensitivity is plotted for background sensitivity and corresponding automated perimetry.A solution in two planes to the 3D distribution of axons in the ONH is *** fields with induced damage in the optic disc are comparable in pattern and quantity to glaucomatous ***:The two-level simulation of the ONH facilitates the analysis of optic-cup/retinal *** can generate the virtual optic pathways tailored to the age and morphology of the patient’s eye,and it is possible to reproduce glaucomatous damage by“reverse engineering”*** virtual cortical model renders a quantitative relationship between visual defect and neural ***:A two-level computing of the retina/optic nerve facilitates the analysis of neuroretinal defects and can be incorporated to automatic perimeters to facilitate visual field analysis.

关键词： Computer modeling early optic pathways neuroretinal defects threshold sensitivity visual fields

Thermal manipulation of plasmons in atomically thin films

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2020年第1期9卷 1179-1189页

作者： Eduardo J.C.Dias Renwen Yu F.javier garc.a de Abajo ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860 Castelldefels(Barcelona)Spain ICREA-Institucio Catalana de Recerca i Estudis Avançats Passeig Lluis Companys 2308010 BarcelonaSpain

Nanoscale photothermal effects enable important applications in cancer therapy,imaging and *** effects also induce substantial changes in the optical response experienced by the probing light,thus suggesting their application in all-optical ***,we demonstrate the ability of graphene,thin metal films,and graphene/metal hybrid systems to undergo photothermal optical modulation with depths as large as>70%over a wide spectral range extending from the visible to the terahertz frequency *** envision the use of ultrafast pump laser pulses to raise the electron temperature of graphene during a picosecond timescale in which its mid-infrared plasmon resonances undergo dramatic shifts and broadenings,while visible and near-infrared plasmons in the neighboring metal films are severely attenuated by the presence of hot graphene *** study opens a promising avenue toward the active photothermal manipulation of the optical response in atomically thin materials with potential applications in ultrafast light modulation.

关键词： pump visible films

Nanoparticles embedded into glass matrices:glass nanocomposites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Materials Science 2022年第3期16卷 1-81页

作者： javier FONSECA Department of Chemical Engineering Northeastern UniversityBoston 02115USA

Research on glass nanocomposites(GNCs)has been very active in the past *** have attracted—and still do—great interest in the fields of optoelectronics,photonics,sensing,electrochemistry,catalysis,biomedicine,and *** this review,the potential applications of GNCs in these fields are briefly described to show the reader the possibilities of these *** most important synthesis methods of GNCs(melt-quenching,sol-gel,ion implantation,ion-exchange,staining process,spark plasma sintering,radio frequency sputtering,spray pyrolysis,and chemical vapor deposition techniques)are extensively *** major aim of this review is to systematize our knowledge about the synthesis of GNCs and to explore the mechanisms of formation and growth of NPs within glass *** size-controlled preparation of NPs within glass matrices,which remains a challenge,is essential for advanced ***,a thorough understanding of GNC synthesis techniques is expected to facilitate the preparation of innovative GNCs.

关键词： glass nanocomposites melt-quenching sol-gel ion implantation ion-exchange

维普期刊数据库

Prevalence of hepatocarcinoma-related hepatitis B virus mutants in patients in grey zone of treatment

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2019年第38期25卷 5883-5896页

作者： Ana Isabel Gil-garc.a Antonio Madejón Irene Francisco-Recuero Ana López-López Emiliana Villafranca Miriam Romero Araceli garc.a Antonio Olveira Rocío Mena Juan Ramón Larrubia javier garc.a-Samaniego Hepatology Unit Hospital Universitario La PazMadrid 28046Spain Centro de Investigación Biomédica en Red Instituto de Salud Carlos IIIMadrid 28029Spain Instituto de Investigación del Hospital Universitario la Paz Madrid 28046Spain Biochemistry Department Faculty of MedicineUniversidad Autónoma de MadridMadrid 28029Spain Instituto de Genética Médica y Molecular Hospital Universitario La PazMadrid 28046Spain Translational Hepatology Unit Hospital General Universitario de GuadalajaraGuadalajara 19002Castilla-La ManchaSpain

BACKGROUND Antiviral treatment of patients with chronic hepatitis B(CHB)in the grey zone of treatment comands risk management in order to optimize the health *** this sense,the identification of HBV mutants related with an increased risk of hepatocellular carcinoma(HCC)could be useful to identify subpopulations with potential indication of antiviral *** To analyze the prevalence/persistence of hepatitis B virus(HBV)preS and basal core promoter(BCP)/precore/core variants associated to HCC development in CHB patients in the grey *** Work was designed as a longitudinal retrospective study,including 106 plasma samples from 31 patients with CHB in the grey zone of treatment:Hepatitis B e antigen negative,HBV-DNA levels between 12-20000 IU/mL,normal or discordant transaminase levels during follow up and mild/moderate necroinflammatory activity in liver biopsy or Fibroscan(up to 9.5 kPa).Serum HBVDNA was tested using the Abbott Real Time HBV Assay and the BCP/precore/core and the hepatitis B surface antigen(HBsAg)coding regions were analyzed in positive samples by PCR/bulk-sequencing to identify the HCCrelated HBV *** High-risk HCC related mutants were detected in 24(77%)patients:19(61%)in the BCP/precore/core,and 7(23%)in the HBsAg coding region(2 preS1 and 5 preS2 deletions).The prevalence of preS deletions was genotype-dependent:3/5(60%)patients with preS2 deletions and 1/2 with preS1 deletions were infected with the HBV-E *** HBV-E was the most prevalent in sub-Saharan patients,a correlation between preS deletions and ethnicity was also found:6/8(75%)sub-Saharan vs 1/19(5%)Caucasian patients had preS deletions(P=0.00016).Remarkably,this correlation was maintained in those patients infected with HBV-A,a minor genotype in sub-Saharan patients:2/2 patients infected with HBV-A from West Africa vs 0/6 of Caucasian origin had preS *** HCC related variants were the major strains and persisted over time(up to 48 mo).Pa

关键词： Hepatitis B virus Hepatocellular carcinoma PreS deletions Hepatitis B virus treatment Grey zone

Nonlinear criterion for strength mobilization in brittle failure of rock and its extension to the tunnel scale

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2022年第4期32卷 685-705页

作者： Rodolfo Cabezas javier Vallejos Faculty of Engineering and Technology Universidad San SebastianSantiagoChile Advanced Mining Technology Center Universidad de ChileSantiagoChile Department of Mining Engineering Universidad de ChileSantiagoChile

As underground excavations are getting deeper and field stresses increase, the behavior of intact rock blocks plays an increasingly important role in understanding and estimating the overall rock mass strength. To model the brittle behavior of intact rock blocks, the stress–strain curve is usually idealized considering a linear strength mobilization approach(cohesion-weakening-friction-strengthening, CWFS),however, it is well recognized that rock presents a nonlinear behavior in terms of the confining *** study extends the strength mobilization in brittle failure of rock using nonlinear criteria. To determine the model parameters, a standard statistical method that uses the complete laboratory stress–strain curves of the intact rock is employed. Several hypotheses of linear and nonlinear models are statistically compared for different types of rock and confining stress levels. Results demonstrate that the best approach to model the brittle failure of rock is to consider a nonlinear strength envelope, such as the Hoek-Brown criterion assuming a residual uniaxial compressive strength different from zero and a mi parameter that increases, both with simultaneous mobilization. This model helps to recreate highconfining conditions and a more realistic transition between peak and post-peak strength. The obtained parameters are discussed and compared with literature values to verify the validity and to develop guidelines for the estimation of parameters, providing an objective mobilization criterion. Finally, the nonlinear model was applied to a finite element code and extended to a tunnel scale in the brittle rock under high-stress conditions. A reasonable fit between the simulations and the in-situ overbreak measurements was found.

关键词： Nonlinear strength Strength mobilization Brittle failure Intact rock Scaling

维普期刊数据库

Evaluation of Ocimum basilicum *** Different Concentrations of K^(+)as an Inhibitor of Pathogenic Bacterial Strains

在线全文

学校读者我要写书评

暂无评论

Phyton-International Journal of Experimental Botany 2021年第2期90卷 533-541页

作者： Mercedes Georgina Ramírez-Aragón Victoria Jared Borroel-garc.a Ramón Valenzuela-Soto Ricardo David Valdez-Cepeda Francisco javier Wong-Corral JoséLuis garc.a-Hernández Universidad Politécnica de Gómez Palacio Gómez Palacio35120México Universidad Autónoma Chapingo Centro Regional Universitario Centro-NorteZacatecasZac.Universidad Autónoma de ZacatecasFacultad de MatemáticasZacatecas98053México Departamento de Investigación y Posgrado en Alimentos Universidad de SonoraHermosillo83000México Facultad de Agricultura y Zootecnia Universidad Juárez del Estado de DurangoGómez Palacio34000México

The extraction of bioactive compounds has become one of the most interesting areas of modern *** therapeutic reasons,it´s important to obtain antimicrobial agents from natural *** objective of the present study was to determine the inhibitory effect of ethanolic extract of basil(Ocimum basilicum *** Rubin)subjected to different concentrations of potassium(K^(+))on the activity of three bacterial strains that are pathogens in *** was evaluated by inhibition surface and these results were compared to two antibiotics:Gentamicin(GE)and Ciprofloxacin(CPF)for their efficacy against each bacterial *** variables presented significant difference(p≤0.05).According to the results,basil extract evaluated showed positive antibacterial activity against the three strains of Pseudomonas aeruginosa,Listeria monocytogenes and Staphylococcus aureus on Mueller Hinton *** was observed highest inhibition areas of different diameters(15.3 mm,21.3 mm and 21.6 mm respectively)when the extract used was obtained from the plants with the highest concentration of potassium(13 mmol L-1).These values were even superior to the highest values showed on the treatments with the antibiotic gentamicin.

关键词： Basil inhibition potassium secondary metabolites antibiotics

On-chip wireless silicon photonics: from reconfigurable interconnects to lab-on-chip devices

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2017年第1期6卷 517-527页

作者： Carlos garc.a-Meca Sergio Lechago Antoine Brimont Amadeu Griol Sara Mas Luis Sánchez Laurent Bellieres Nuria S Losilla javier Martí Nanophotonics Technology Center Universitat Politècnica de València46022 ValenciaSpain

Photonic integrated circuits are developing as key enabling components for high-performance computing and advanced networkon-chip,as well as other emerging technologies such as lab-on-chip sensors,with relevant applications in areas from medicine and biotechnology to *** demanding applications will require novel features,such as dynamically reconfigurable light pathways,obtained by properly harnessing on-chip optical *** this paper,we introduce a broadband,high directivity(4150),low loss and reconfigurable silicon photonics nanoantenna that fully enables on-chip radiation *** propose the use of these nanoantennas as versatile building blocks to develop wireless(unguided)silicon photonic devices,which considerably enhance the range of achievable integrated photonic *** examples of applications,we demonstrate 160 Gbit s−1 data transmission over mm-scale wireless interconnects,a compact low-crosstalk 12-port crossing and electrically reconfigurable pathways via optical beam ***,the realization of a flow micro-cytometer for particle characterization demonstrates the smart system integration potential of our approach as lab-on-chip devices.

关键词： integrated optics lab-on-a-chip devices nanoantenna sensing silicon photonics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

See how atoms dance

National Science Review 2020年第5期7卷 833-834页

作者： javier Aizpurua Center for Materials Physics (CSIC-UPV/EHU) DIPC

As for any other wave, classical light was often thought to be constrained by the diffraction limit. However, since the pioneering works in near-field microscopy,in which the evanescent components of light localized a... 详细信息

关键词： See how atoms dance

Probabilistic Constructions of B_2[g] Sequences

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2010年第7期26卷 1309-1314页

作者： javier CILLERUELO Instituto de Ciencias Matermáticas(CSIC-UAM-UCM) Department of Mathematics Universidad Autónoma de Madrid

We use the probabilistic method to prove that for any positive integer g there exists an infinite B2[g] sequence A = {ak} such that ak ≤ k^2＋1/g（log k）^1/g＋0（1） as k→∞. The exponent 2＋1/g improves the previo... 详细信息

关键词： Sidon sets B2 [g] sequences probabilistic method

维普期刊数据库