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Retrieval of Elastic Green’s Tensor near a Cylindrical Inhomogeneity from Vector Correlations

Communications in Computational Physics 2008年第1期3卷 250-270页

作者： juan AP´erez-Ruiz francisco Luzon francisco j.sanchez-sesma Grupo de Geof´ısica Aplicada Departamento de F´ısica AplicadaUniversidad de Almer´ıaCa˜nada de San Urbano s/n04120-Almer´ıaSpain Departamento de Sismolog´ıa Instituto de IngenieriaUniversidad Nacional Aut´onoma de M´exicoCd.UniversitariaCircuito Escolar s/nCoyoac´an 04510M´exico D.F.Mexico.

Multiple scattering of elastic waves in realistic media makes that averagefield intensities or energy densities follow diffusive processes. In such regime the successiveP to S energy conversions by distributed random inhomogeneities give rise toequipartition which means that in the phase space the available elastic energy is distributedin averagewith equal amounts among the possible states of P and S waves. Insuch diffusive regime the P to S energy ratio equilibrates in an universal way independentof the particular details of the scattering. It has been demonstrated that averagingthe cross correlations at any two points of an elastic medium subjected to diffuse elasticwavefields leads to the emergence of the Green function, which is the wave fieldthat would be observed at one position if an impulsive load is applied at the other. Inthis work we study the problem of the retrieval of the 2D tensor elastodynamic Greenfunction in an infinite elastic space containing a circular cylinder inclusion. We illuminateisotropically the elastic spacewith plane waves. We assume the spectra for both Pand S waves uniform but such that the energy ratio ES/EP=(a/b)2, which is the onepredicted by equipartition theory in two-dimensions. We then show that the Fouriertransform of azimuthal average of the cross-correlation of motion between two pointswithin an elastic medium is proportional to the imaginary part of the exact Green tensorfunction between these points. The numerical results presented here point out thepossibility of detection and imaging of diffractors and resonant diffractors by crosscorrelation even in presence of attenuation exists.

关键词： Multiple scattering elastic waves elastic Green’s tensor

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Agglomerate behavior in a recirculating fluidized bed with sheds： Effect of ring baffles

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Particuology 2018年第3期16卷 143-151页

作者： francisco j. sanchez Careaga Cedric Briens Franco Berruti jennifer McMillan Murray Gray Institute for Chemicals and Fuels from Alternative Resources Western University 22312 Wonderland Rd. Hderton ON NO M2AO Canada Edmonton Research Centre Syncrude Canada Ltd 9421 17th Ave Edmonton AB T6N 1H4 Canada The Petroleum Institute PO Box 2533 Abu Dhabi UAE

The radioactive particle tracking technique was used to study the effect of internal ring baffles on wet agglomerate motion inside a cold flow recirculating fluidized bed. The study found that using such a baffle on its own or above the regular sheds helps reduce the fouling of the stripper section by increasing the residence time that the agglomerates spend above the baffle, thereby reducing the release of the vapors below the baffles that cause fouling of the sheds. Adding down-comers, or flux tubes, to the ring baffles degrades the performance of the baffles, Reducing the length of the flux tubes, so that they do not reach the bottom of the baffle lip results in a further degradation in baffle performance.

关键词： Radioactive particle tracking Fluidized bed Fluid coker Baffles

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Redox Regulation of Glycogen Biosynthesis in the Cyanobacterium Synechocystis sp. PCC 6803： Analysis of the AGP and Glycogen Synthases

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Molecular Plant 2014年第1期7卷 87-100页

作者： Sandra Diaz-Troya Luis Lopez-Maury Ana Maria sanchez-Riego Miguel Roldan francisco j. Florencio Instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla-CSIC Americo Vespucio 49 E-41092 Sevilla Spain

Glycogen constitutes the major carbon storage source in cyanobacteria, as starch in algae and higher plants. Glycogen and starch synthesis is linked to active photosynthesis and both of them are degraded to glucose in the dark to maintain cell metabolism. Control of glycogen biosynthesis in cyanobacteria could be mediated by the regulation of the enzymes involved in this process, ADP-glucose pyrophosphorylase （AGP） and glycogen synthase, which were identified as putative thioredoxin targets. We have analyzed whether both enzymes were subjected to redox modification using purified recombinant enzymes or cell extracts in the model cyanobacterium Synechocystis sp. PCC 6803. Our results indicate that both AGP and glycogen synthases are sensitive to copper oxidation. However, only AGP exhibits a decrease in its enzymatic activity, which is recovered after reduction by DTT or reduced thioredoxin （TrxA）, suggesting a redox control of AGP. In order to elucidate the role in redox control of the cysteine residues present on the AGP sequence （C45, C185, C320, and C337）, they were replaced with serine. All AGP mutant proteins remained active when expressed in Synechocystis, although they showed different electrophoretic mobility profiles after copper oxidation, reflecting a complex pattern of cysteines interaction.

关键词： cyanobacteria glycogen Synechocystis thioredoxin redox regulation.

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Ferrofluid moving thin films for active flow control

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Chinese journal of Aeronautics 2021年第5期34卷 115-119页

作者： francisco j.ARIAS Department of Fluid Mechanics Polytechnic University of CataloniaESEIAATC/Colom 1108222 BarcelonaSpain

Ferrofluid moving thin films and their possible significance with regard to active flow control for lift and attack angle enhancement are *** this strategy,a very thin film of ferrofluid is strongly attached at the wall of the wing by a normal magnetic field from below and pumped tangentially along the *** a simplified physical model and from the available experimental data on moving walls,the expected lift enhancement and effect on the attack angle were *** research and design is required in order to explore the possibilities in the use of ferrofluid moving thin films.

关键词： Active flow control Boundary layer separation Ferrofluid

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Local Fourier Analysis for Edge-Based Discretizations on Triangular Grids

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 78-96页

作者： Carmen Rodrigo francisco Sanz francisco j.Gaspar francisco j.Lisbona Department of Applied Mathematics University of ZaragozaC/Maria de Luna 350018ZaragozaSpain BIFI University of Zaragoza C/Pedro Cerbuna 1250009ZaragozaSpain Department of Applied Mathematics University of ZaragozaC/Pedro Cerbuna 1250009ZaragozaSpain

In this paper,we present a local Fourier analysis framework for analyzing the different components within multigrid solvers for edge-based discretizations on triangular *** different stencils associated with edges of different orientation in a triangular mesh make this analysis *** resulting tool is demonstrated for the vector Laplace problem discretized by mimetic finite difference *** from the local Fourier analysis,as well as experimentally obtained results,are presented to validate the proposed analysis.

关键词： Multigrid local Fourier analysis edge-based discretizations mimetic finite differences

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Possible implications of dysregulated nicotinic acetylcholine receptor diffusion and nanocluster formation in myasthenia gravis

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Neural Regeneration Research 2021年第2期16卷 242-246页

作者： francisco j.Barrantes Biomedical Research Institute(BIOMED)UCA-CONICET Buenos AiresArgentina

Myasthenia gravis is a rare and invalidating disease affecting the neuromuscular junction of voluntary *** classical form of this autoimmune disease is characterized by the presence of antibodies against the most abundant protein in the neuromuscular junction,the nicotinic acetylcholine *** variants of the disease involve autoimmune attack of non-receptor scaffolding proteins or enzymes essential for building or maintaining the integrity of this peripheral *** review summarizes the participation of the above proteins in building the neuromuscular junction and the destruction of this cholinergic synapse by autoimmune aggression in myasthenia *** review also covers the application of a powerful biophysical technique,superresolution optical microscopy,to image the nicotinic receptor in live cells and follow its motional *** hypothesis is entertained that anomalous nanocluster formation by antibody crosslinking may lead to accelerated endocytic internalization and elevated turnover of the receptor,as observed in myasthenia gravis.

关键词： agrin autoimmune diseases muscle end-plate muscle specific kinase MuSK myasthenia gravis nanoscopy neuromuscular junction nicotinic acetylcholine receptor rapsyn superresolution microscopy

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Impaired immune reaction and increased lactate and C-reactive protein for early prediction of severe morbidity and pancreatic fistula after pancreatoduodenectomy

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Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 58-67页

作者： Mario Rodriguez-Lopez francisco j.Tejero-Pintor Martin Bailon-Cuadrado Asterio Barrera-Rebollo Baltasar Perez-Saborido David Pacheco-sanchez General and Digestive Surgery Department Rio-Hortega University Hospital

Background: Prediction of complications after pancreatoduodenectomy (PD) remains of interest. Blood parameters and biomarkers during rst and second postoperative days (POD1, POD2) may be early indi- cators of complications. Methods: This case-control study included 50 patients. Baseline, POD1 and POD2 values of leukocytes, neutrophils, lymphocytes, platelets, hemoglobin, C-reactive protein (CRP), procalcitonin and arterial lactate were compared between individuals presenting Clavien ≥ III morbidity, pancreatic stula (PF) or clinically relevant PF (CRPF) and those without these morbidities. Common variables reaching signi cance were further analyzed in order to calculate a predictive score. Results: Severe morbidity, PF and CRPF rates were 28.0%, 26.0% and 14.0%, respectively. Patients with severe morbidity had lower leukocytes on POD2 (P=0.04). Patients with PF presented higher CRP on POD2 (P=0.001), higher lactate on POD1 (P=0.007) and POD2 (P=0.008), and lower lymphocytes on POD1 (P=0.007) and POD2 (P=0.008). Patients with CRPF had lower leukocytes and neutrophils on POD1 (P =0.048, P =0.038), lower lymphocytes on POD1 (P =0.001) and POD2 (P =0.003), and higher CRP on POD2 (P =0.001). Baseline parameters and procalcitonin obtained no statistical associations. Score was de ned according to lymphocytes on POD1 < 650/μL and CRP on POD2 ≥ 250 mg/L allocating patients in 3 risk categories. PF and CRPF rates were statistically higher as risk category increased (P<0.001). Receiver operating characteristic curves and Hosmer Lemeshow tests showed a good accuracy. Conclusions: Impaired immunological reaction during early postoperative period (lower leukocytes and, particularly, lymphocytes) in response to surgical aggression would favor complications after PD. Likewise, acidosis (higher arterial lactate) could behave as risk factor of PF. An elevated CRP on POD2 is also an early biomarker of PF. Our novel score based on postoperative lymphocyte count and CRP seems reliable

关键词： Pancreatoduodenectomy Morbidity Pancreatic fistula Biomarker Prediction Score

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Controversies around the treatment of peritoneal metastases of colorectal cancer

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World journal of Gastrointestinal Oncology 2025年第1期17卷 260-264页

作者： francisco j Morera-Ocon Clara Navarro-Campoy Ticiano Guastella francisco Landete-Molina Department of General Surgery Hospital General de RequenaRequena 46340Spain Department of Gynecology and Obstetrics Hospital 9 OctubreValencia 46015Spain Department of Pathology Hospital General de RequenaRequena 46340Spain

In this editorial we examine the article by Wu et al published in the World journal of Gastrointestinal *** resection for peritoneal metastases from colorectal cancer(CRC)has been gradually accepted in the medical oncology community.A randomized trial(PRODIGE 7)on cytoreductive surgery(CRS)with hyperthermic intraperitoneal chemotherapy(HIPEC)failed to prove any benefit of oxaliplatin in the overall survival of patients with peritoneal metastases from colorectal ***,isolated systemic chemotherapy for CRC stage IV has demonstrated a reduced response in peritoneal metastases than that obtained in other metastatic sites such as the *** tool is required in those patients to achieve more local control of the *** groups in peritoneal surgery continue to use HIPEC in their procedures,using other agents than oxaliplatin for peritoneal cavity infusion,such as mitomycin *** patients present with complex surgical issues to manage,and consequently a large burden of complications has to be ***,identifying patients who will benefit from CRS with or without HIPEC would be of great interest.

关键词： Colorectal cancer Peritoneal metastasis Hyperthermic intraoperative chemotherapy Treatment strategies Peritoneal Surface Oncology GroupInternational

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Severe morbidity after pancreatectomy is accurately pre dicte d by preoperative pancreatic resection score(PREPARE): A prospective validation analysis from a medium-volume center

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 559-565页

作者： Mario Rodriguez-Lopez francisco j. Tejero-Pintor Baltasar Perez-Saborido Asterio Barrera-Rebollo Martin Bailon-Cuadrado David Pacheco-sanchez General and Digestive Surgery Department Rio-Hortega University Hospital

Background: Major morbidity in pancreatic surgery remains high. Different scores for predicting complications have been described. Preoperative pancreatic resection(PREPARE) score is based on objective preoperative variables and offers good predictive accuracy for Clavien ≥ III complications. This study aimed to validate this score and analyze other preoperative variables in a prospective study performed in a medium-volume center. Methods: A total of 50 pancreatic resections were included. Preoperative variables were registered and PREPARE was calculated. The main outcome was severe morbidity(Clavien ≥ III) up to 30 days after discharge. The secondary outcomes were length of stay(LOS) and readmission. Statistical validation was performed to compare severe morbidity rate among the scores categories. Association with other preoperative variables(not included in PREPARE) was also tested. Results: Of the 50 pancreatic resections, the severe morbidity was 34.0%, with median LOS of 11 days. Readmission rate was 25.5%. Severe morbidity rates according to PREPARE categories were 18.5% in lowrisk group, 41.7% in intermediate-risk group, and 63.6% in high-risk group, respectively( P = 0.023). The accuracy was 72%(Hosmer–Lemeshow, P = 0.86). ROC curve was obtained both for PREPARE score expressed as incremental values and categorized as the three risk groups, showing an area under curve(AUC) of 0.736(95% CI: 0.586–0.887; P = 0.007) and 0.712(95% CI: 0.555–0.869; P = 0.015), respectively. PREPARE was significant in multivariate analysis. Median LOS was statistically higher as PREPARE category increases(9, 11 and 15 days in low-, intermediate-and high-risk groups, respectively; P = 0.009). Readmission was not associated with any variables. Conclusions: PREPARE behaves as an independent risk factor for severe morbidity after pancreatic surgery. Score validation shows good accuracy prediction. Increasing PREPARE category is also associated with longer LOS.

关键词： Pancreatic surgery Morbidity Complications Preoperative pancreatic resection score Validation

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Shear velocity criterion for incipient motion of sediment

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Water Science and Engineering 2014年第2期7卷 183-193页

作者： francisco j.M.SIMOES U.S. Geological Survey Geomorphology and Sediment Transport LaboratoryGolden CO 80403 USA

The prediction of incipient motion has had great importance to the theory of sediment transport. The most commonly used methods are based on the concept of critical shear stress and employ an approach similar, or identical, to the Shields diagram. An alternative method that uses the movability number, defined as the ratio of the shear velocity to the particle＇s settling velocity, was employed in this study. A large amount of experimental data were used to develop an empirical incipient motion criterion based on the movability number. It is shown that this approach can provide a simple and accurate method of computing the threshold condition for sediment motion.

关键词： incipient motion sediment transport Shields diagram critical shear stress criticalshear velocity movability number

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