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Friction 2014年第2期2卷 193-208页

作者： pedro A.ROMERO Lars PAsTEWKA Julian VON LAUTZ Michael MOsELER Fraunhofer Institute for Mechanics of Materials IWM Wöhlerstraße 1179108 FreiburgGermany Karlsruhe Institute of Technology IAM-ZBSKaiserstraße 1276131KarlsruheGermany Freiburg Materials Research Center Stefan-Meier-Straße 2179104FreiburgGermany University of Freiburg Physics DepartmentHermann-Herder-Straße 379104 FreiburgGermany

Tetrahedral amorphous carbon coatings have the potential to significantly reduce friction and wear between sliding ***,we provide atomistic insights into the evolution of the sliding interface between naked and hydrogen-passivated ta-C sliding partners under dry and lubricated *** reactive classical atomistic simulations we show that sliding induces a sp3 to sp2 rehybridization and that the shear resistance is reduced by hydrogen-passivation and hexadecane-lubrication-despite our finding that nanoscale hexadecane layers are not always able to separate and protect ta-C counter surfaces during *** asperities deform,carbon atoms within the hexadecane lubricant bind to the ta-C sliding partners resulting in degradation of the hexadecane molecules and in increased material intermixing at the sliding *** atoms from the passivation layer and from the hexadecane chains continue to be mixed within a sp2 rich sliding interface eventually generating a tribo-layer that resembles an a-C:H type of *** separation of the sliding partners,the tribo-couple splits within the newly formed sp2 rich a-C:H mixed layer with significant material transfer across the sliding *** leaves behind a-C:H coated ta-C surfaces with dangling C bonds,linear C chains and hydrocarbon fragments.

关键词： Atomic-scale simulations DLC lubrication hexadecane passivation sliding mixed layer wear

seamless and non-repetitive 4D texture variation synthesis and real-time rendering for measured optical material behavior

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Computational Visual Media 2019年第2期5卷 161-170页

作者： Martin Ritz simon Breitfelder pedro santos Arjan Kuijper Dieter W. Fellner Fraunhofer IGD Darmstadt64283Germany TU Darmstadt Darmstadt64289Germany TU Graz Graz8010Austria

We show how to overcome the single weakness of an existing fully automatic system for acquisition of spatially varying optical material behavior of real object surfaces. While the expression of spatially varying material behavior with spherical dependence on incoming light as a 4D texture(an ABTF material model) allows flexible mapping onto arbitrary 3D geometry, with photo-realistic rendering and interaction in real time,this very method of texture-like representation exposes it to common problems of texturing, striking in two disadvantages. Firstly, non-seamless textures create visible artifacts at boundaries. secondly, even a perfectly seamless texture causes repetition artifacts due to their organised placement in large numbers over a 3D surface. We have solved both problems through our novel texture synthesis method that generates a set of seamless texture variations randomly distributed over the surface at shading time. When compared to regular 2D textures, the inter-dimensional coherence of the 4D ABTF material model poses entirely new challenges to texture synthesis, which includes maintaining the consistency of material behavior throughout the 4D space spanned by the spatial image domain and the angular illumination hemisphere. In addition, we tackle the increased memory consumption caused by the numerous variations through a fitting scheme specifically designed to reconstruct the most prominent effects captured in the material model.

关键词： optical material behavior reflectance modeling 4D texture synthesis texturing

Plateau archives of lithosphere dynamics,cryosphere and paleoclimate:The formation of Cretaceous desert basins in east Asia

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Geoscience Frontiers 2022年第6期13卷 170-181页

作者： Chihua Wu Juan pedro Rodríguez-López M.santosh state Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China PAGODA Research Group(Plateau&Global Desert Basins Research Group) Institute of Sedimentary GeologyChengdu University of TechnologyChengdu 610059China Permafrost Laboratory Department of GeographyUniversity of SussexFalmerBrighton BN19SJUnited Kingdom school of Earth science and Resources China University of Geosciences29 Xueyuan RoadBeijing 100083China Department of Earth sciences University of AdelaideSA 5005Australia

southeastern Eurasia is a global window to the Cretaceous paleoclimate and lithosphere *** contains one of the most complete and complex sedimentary records of Mesozoic desert basins on planet *** this study,we perform the spatio-temporal tracking of 96 Cretaceous palaeoclimate indicators during 79 Myr which reveal that the plateau paleoclimate archives from East Asia resulted from an Early to Mid-Cretaceous ocean–atmosphere coupling and a shift to a preponderant role of Late Cretaceous lithosphere dynamics and tectonic forcing on high-altitude depositional systems linked to the subduction margins of the Tethys and Paleo-Pacific realms beneath the Eurasian *** crustal response to tectonic processes linked with the spatio-temporal evolution of the Tethyan and Paleo-Pacific margins defined the configuration of major sedimentary basins on this *** significant increase and decrease in the number of active sedimentary basins that occur during the Cretaceous,from 16 in the Early Cretaceous,to 28 in the Mid-Cretaceous,and a decreasing to 20 sedimentary basins in the Late Cretaceous,is a direct response of lithospheric dynamics associated with the two main subduction zones(Tethys and Pacific domains).A shift in subduction style from an Early Cretaceous Paleo-Pacific Plate slab roll back to a Late Cretaceous flat-slab mode might have triggered regional plateau uplift,blocked intraplate volcanism,thus enhancing the denudation and sediment availability,and created wind corridors that led to the construction and accumulation of extensive Late Cretaceous aeolian sandy deserts(ergs)that covered Mid-Cretaceous plateau *** the same time,plateau uplift associated with crustal thickening following terrane assembly in the Tethyan margin triggered altitudinal cryospheric processes in sandy desert *** of an active Cretaceous cryosphere in China include ValanginianHauterivian glacial debris flows,Early Aptian geochemical signature of melt w

关键词： Cretaceous Cryosphere Aeolian Plateau subduction Asia

Trifocal toric intraocular lenses in eyes with low amount of corneal astigmatism

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International Journal of Ophthalmology(English edition) 2020年第10期13卷 1567-1573页

作者： Paz Orts-Vila salvador Aguilar-Corcoles Cristina Tello-Elordi María Ramos-Alzamora Robert Montés-Mico pedro Taná-Rivero Oftalvist Clinic Alicante 03001Spain Optics and Optometry&Vision sciences Department University of ValenciaBurjassotValencia 46100Spain

AIM:To evaluate the refractive and visual outcomes following cataract surgery and implantation of a trifocal toric intraocular lens(IOL)in eyes with low degrees of corneal ***:Twenty-six eyes of 22 patients who underwent implantation a trifocal toric IOL(FineVision PODFT,PhysIOL s.a.,Liege,Belgium)were *** with femtosecond laser,capsular tension ring insertion and intraoperative aberrometry were performed in all *** IOLs used showed a cylinder power of 1.00 *** outcome measures were refractive error and corrected-distance visual acuity(CDVA)and uncorrected-distance visual acuity(UDVA)*** were evaluated at 4 mo ***:Totally 50%of eyes showed a spherical equivalent(sE)within±0.13 D and all of them within±0.50 *** mean sE and refractive cylinder were-0.02±0.23 and-0.16±0.22 D,*** analysis revealed that 100%of eyes were within±0.50 D for the sE and cylindrical components(J0 and J45).Refractive changes were not correlated with keratometric changes(P>0.05)showing that the reduction in astigmatism comes from the trifocal toric *** 81%and 96%of eyes showed UDVA and CDVA of 20/20,*** postoperative mean values of monocular distance snellen decimal UDVA and CDVA were 0.97±0.05 and 0.99±0.02(about 20/20),***:Our study suggests that the use of this trifocal toric IOL in patients with low amount of astigmatism provides accurate refractive outcomes and enables them to achieve excellent visual acuity.

关键词： toric trifocal intraocular lens phacoemulsification cataract astigmatism

Glycoprotein biomarkers for the detection of pancreatic ductal adenocarcinoma

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World Journal of Gastroenterology 2018年第24期24卷 2537-2554页

作者： Esther Llop pedro E Guerrero AdriàDuran sílvia Barrabés Anna Massaguer María JoséFerri Maite Albiol-Quer Rafael de Llorens Rosa Peracaula Department of Biology Biochemistry and Molecular Biology UnitUniversity of GironaGirona 17003Spain Biomedical Research Institute of Girona(IdIBGi).Parc Hospitalari Martíi Julià-Edifici M2 Salt 17190Spain Clinic Laboratory University Hospital Dr Josep TruetaGirona 17007Spain Department of surgery Hepato-biliary and Pancreatic Surgery UnitUniversity Hospital Dr Josep TruetaGirona 17007Spain

Pancreatic cancer(Pa C) shows a clear tendency to increase in the next years and therefore represents an important health and social challenge. Currently, there is an important need to find biomarkers for PaC early detection because the existing ones are not useful for that purpose. Recent studies have indicated that there is a large window of time for PaC early detection, which opens the possibility to find early biomarkers that could greatly improve the dismal prognosis of this tumor. The present manuscript reviews the state of the art of the existing PaC biomarkers. It focuses on the anomalous glycosylation process and its role in PaC. Glycan structures of glycoconjugates such as glycoproteins are modified in tumors and these modifications can be detected in biological fluids of the cancer patients. several studies have found serum glycoproteins with altered glycan chains in PaC patients, but they have not shown enough specificity for PaC. To find more specific cancer glycoproteins we propose to analyze the glycan moieties of a battery of glycoproteins that have been reported to increase in PaC tissues and that can also be found in serum. The combination of these new candidate glycoproteins with their aberrant glycosylation together with the existing biomarkers could result in a panel, which would expect to give better results as a new tool for early diagnosis of PaC and to monitor the disease.

关键词： Pancreatic cancer Aberrant glycosylation Glycoproteins Biomarkers Diagnosis

Gene transcription profiting of astheno-and normo-zoospermic sperm subpopulations

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Asian Journal of Andrology 2020年第6期22卷 608-615页

作者： pedro Caballero-Campo saul Lira-Albarran David Barrera Elizabeth Borja-Cacho Hector s Godoy-Morales Claudia Rangel-Escareno Fernando Larrea Mayel Chirinos Department of Reproduction Biology National Institute of Medical Sciences and Nutrition Salvador ZubiranMexico City 14080Mexico Tambre Foundation Madrid 28002Spain Reproductive Medicine Unit Angeles del Ped regal HospitalMexico City 10700Mexico Computational Genomic and Integrative Biology Laboratory National Institute of Genomic MedicineMexico City 14610Mexico

spermatozoa contain a repertoire of RNAs considered to be potential functional fertility *** this study,the gene expression of human sperm subpopulations with high(F1)and low(F2)motility from healthy normozoospermic(N)and asthenozoospermic(A)individuals was evaluated using RNA microarray followed by functional genomic analysis of differentially expressed *** from A-F1 versus N-F1,A-F2 versus N-F2,N-F1 versus N-F2,and A-F1 versus A-F2 comparisons showed a considerably larger set of downregulated genes in tests versus *** ontology(GO)analysis of A-F1 versus N-F1 identified 507 overrepresented biological processes(BPs),several of which are associated with sperm *** addition,gene set enrichment analysis of the same contrast showed 110 BPs,36 cellular comp on ents,and 31 molecular functions,several of which are involved in sperm motility.A leadi ng・edge analysis of selected GO terms resulted in several down regulated genes encoding to dyn eins and kin esins,both related to sperm ***,the predicted activation state of asthenozoospermia was increased,while fertility,cell movement of sperm,and gametogenesis were ***,several downregulated genes characteristic of the canonical pathway protein ubiquitination were involved in asthenozoospermia ***,GO analysis of A-F2 versus N-F2 did not identify overrepresented BPs,although the gene set enrichment analysis detected six enriched BPs,one cellular component,and two molecular ***,the results show differences in gene transcription between sperm subpopulations from asthenozoospermic and normozoospermic semen samples and allowed the identification of gene sets relevant to sperm physiology and reproduction.

关键词： asthenozoospermia male in fertility microarray sperm transcriptome

Thiosemicarbazones synthesized from Acetophenones: Tautomerism, spectrometric Data, Reactivity and Theoretical Calculations

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International Journal of Analytical Mass spectrometry and Chromatography 2019年第2期7卷 19-34页

作者： Belén Gastaca Hernán Rubén sánchez Fiorella Menestrina Maricel Caputo María de las Mercedes schiavoni Jorge Javier pedro Furlong Laboratory of Organic Compounds studies (LADECOR) Department of Chemistry Facultad de Ciencias Exactas National University of La Plata La Plata Argentina Institute of Physics of Liquids and Biological systems (IFLysIB CONICET) National University of La Plata La Plata Argentina Laboratory of Research and Development of Analytical Methods (LIDMA) Department of Chemistry Facultad de Ciencias Exactas National University of La Plata La Plata Argentina

Tautomeric forms of Thiosemicarbazones have been investigated by spectrometric methods, their chemical reactivity and theoretical calculations of the relative tautomers stabilities. The mass spectral fragmentation of thiosemicarbazones synthesized from acetophenones has been studied by CG/Ms. The analysis of the corresponding spectra shows not only the regular fragmentation mechanisms but homolytic ruptures from even-electron species. 1H NMR spectra exhibit signals for the most intense open thioketo tautomeric structure, although when using TFA a ring structure is observed in the corresponding tautomeric equilibrium. Density Functional Theory calculations (DFT) also provide evidence to support the experimental observations by GC-Ms and 1H NMR. Methylation reactions give support to the occurrence of the thioenol tautomeric form which would be the second most abundant according to the Density Functional Theoretical calculations.

关键词： Thiosemicarbazones Tautomerism Ms NMR Theoretical Calculations

Pedestrian street and its effect on economic sustainability of a historical Middle Eastern city:The case of Chaharbagh Abbasi in Isfahan,Iran

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Geography and sustainability 2023年第3期4卷 188-199页

作者： soudabeh shahmoradi sayyed Mahdi Abtahi pedro Guimaraes Department of urban planning Iranian Knowledge-Based Company of Pezhvak Tarh IranianIsfahan Science and Technology TownIsfahan University of Technology BlvdIsfahanIran Department of Civil Engineering Isfahan University of TechnologyIsfahanIran Centre of Geographical studies Associated Laboratory TERRAInstitute of Geography and Spatial PlanningLisboaPortugal

Pedestrianization is an urban revitalization strategy to enhance sustainability and livability in car-oriented *** many studies in this research field,the effects of pedestrianization on the economy of cities in developing countries still need further ***,the impact of this strategy on the tenant mix of com-mercial and historical areas in Middle East countries is *** address these inadequacies,we considered Chaharbagh Abbasi street,located in the heart of Isfahan,Iran,and investigated the impact of a pedestrianization project with particular emphasis on how it affects the economic sustainability of existent commercial ***-and post-project data along with field observations and quantifications used to assess structural replacements in trade,were analyzed with sPss and ArcGIs *** results revealed unexpected outcomes,such as the closure of some traditional businesses(27.5%),a stagnation in sales(69%)and a decrease in job offers(84%)leading the local economy to a fragile ***,it was found that the footfall volume increased by 64% and 73% from the retailers’and pedestrians’*** evolution along with a wide opening of food and beverage stores(approximately 60%)makes the post-pedestrianization results more promising than earlier *** conclusion,these findings reinforce the importance of pedestrian streets in revitalizing economic activities in historical and commercial areas from the perspective of economic *** to the lack of similar investigations in Middle East countries,these findings can support decision-makers and urban planners to take preventive measures in preserving the diversity of individual small shops for upcoming urban rehabilitation projects in terms of pedestrianization.

关键词： Urban planning Pedestrianization Chaharbagh abbasi sustainable Development Goals(sDGs) Economic sustainability Historic city centers

The Design of Heat Exchangers

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Engineering（科研） 2011年第9期3卷 911-920页

作者： Arturo Reyes-León Miguel Toledo Velázquez pedro Quinto-Diez Florencio sánchez-silva Juan Abugaber-Francis Celerino Reséndiz-Rosas 不详

A relation between heat transferred and energy loss, for turbulent flow. In different tube arrangements, is made. The conditions are determined which decide the dimensions and velocities for a heat exchanger. Also, a reference to the economic dimensioning of heat exchangers is presented. In this study, the conditions which a heat exchanger must satisfy represent the best balance between the amounts of material employed. The investigation is restricted to the case of turbulent flow.

关键词： Heat Changers Energy Loss Economic Dimensioning Counterflow Crossflow and Parallelflow

Angle-to-angle and spur-to-spur distance analysis with high-resolution optical coherence tomography

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Eye and Vision 2020年第1期7卷 399-411页

作者： Robert Montés-Micó pedro Tañá-Rivero salvador Aguilar-Córcoles María Ruiz-santos María Dolores Rodríguez-Carrillo Ramón Ruiz-Mesa Oftalvist Alicante and Jerez de la FronteraAlicanteSpain University of Valencia ValenciaSpain

Background:To measure angle-to-angle(ATA)and spur-to-spur(sTs)distances along six meridians using highresolution swept-source optical coherence tomography(ss-OCT)and to compare those values with horizontal white-to-white(WTW)***:68 eyes from 68 patients were quantitatively assessed with the Anterion ss-OCT(Heidelberg Engineering,Heidelberg,Germany).ATA and sTs distances were measured with the ss-OCT’s B-scan in six cross-sectional images corresponding to the vertical(6-12 o’clock),1-7 o’clock,2-8 o’clock,horizontal(3-9 o’clock),4-10 o’clock and 5-11 o’clock *** was measured horizontally with the device’s infrared camera.A Pearson correlation analysis was carried out to compare ATA and sTs distances with ***:The largest values were found for the vertical meridian and the shortest for the 2-8 o’clock meridian,both for ATA and sTs *** statistically significant differences were found between WTW,ATA and sTs along the horizontal meridian(p>0.1).However,ATA and sTs showed statistically significant differences elsewhere,except for the horizontal and the 2-8 o’clock meridians(p>0.05).Moreover,we found that ATA and sTs varied significantly depending on the meridian being assessed,except for ATA at 4-10 versus 3-9 o’clock and for sTs at 4-10 versus 3-9 o’clock and at 3-9 versus 2-8 o’clock(p>0.1).R^(2) values ranged from 0.49 to 0.75 for ATA and sTs at the different meridians,showing the best correlation at 3-9 o’clock meridian(0.64 and 0.75,respectively)and the worst at 6-12 o’clock meridian(R^(2)=0.49 for both ATA and sTs).Conclusions:ATA and sTs distances vary radially,thus showing that the anterior chamber is vertically ***,it is advisable to measure these two distances along the meridian to be used.

关键词： Angle-to-angle spur-to-spur White-to-white Optical coherence tomography swept-source Fourier domain

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