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Flow Behavior of Clay-Silt to Sand-Silt Water-Rich Suspensions at Low to High Shear Rates: Implications for Slurries, Transitional Flows, and Submarine Debris-Flows

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2395-2404页

作者： Pierdomenico DEL GAUDIO guido VENTURA Istituto Nazionale di Geofisica e Vulcanologia Via di Vigna Murata 60500143 RomeItaly Istituto per l'Ambiente Marino Costiero Consiglio Nazionale delle RicercheNaplesItaly

Water-rich clay to sand suspensions show a shear rate dependent flow behavior and knowledge of the appropriate rheological model is relevant for sedimentological, industrial and hydraulic studies. We present experimental rheological measurements of water-rich(40 to 60 wt%) clay to silt(population A) and silt to sand(population B) suspensions mixed in different proportions. The data evidence a shear rate dependent shear thinning-shear thickening transition. At lower shear rates, the suspensions organize in chains of particles, whereas at higher shear rates, these chains disrupt so increasing the viscosity. The viscosity, consistency and yield stress decrease as the A+B fraction decreases as the content of B particles increases. This behavior reflects the competing effects of the lubrication and frictional processes as a function of particle size and water content. Transitional flows form by the incorporation of small amounts of the finer fraction while ‘oceanic floods’ form at the estuary of rivers and the submarine debris-flows increase their velocity by incorporating water. The critical Reynolds number of the studied suspensions is ～2000±100 suggesting that the grainsize plays a major role in the laminar to turbulent transition. Our results have implications for the modeling of sediment flows and the hazard related to floods.

关键词： rheology water-sediment suspensions slurry sludge transitional flows and mud flows volcanogenic sediment-water flows oceanic floods

Impact of climate change on hydropower generation in Rio Jubones Basin, Ecuador

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Water Science and Engineering 2018年第2期11卷 157-166页

作者： Mohammad Mehedi Hasan guido Wyseure Hydraulic Research Directorate River Research Institute Department of Earth and Environmental Sciences KU Leuven

This study attempted to use the soil and water assessment tool(SWAT), integrated with geographic information systems(GIS), for assessment of climate change impacts on hydropower generation. This methodology of climate change impact modeling was developed and demonstrated through application to a hydropower plant in the Rio Jubones Basin in Ecuador. ArcSWAT 2012 was used to develop a model for simulating the river flow. The model parameters were calibrated and validated on a monthly scale with respect to the hydro-meteorological inputs observed from 1985 to 1991 and from 1992 to 1998, respectively. Statistical analyses produced Nash-Sutcliffe efficiencies(NSEs) of 0.66 and 0.61 for model calibration and validation, respectively, which were considered acceptable. Numerical simulation with the model indicated that climate change could alter the seasonal flow regime of the basin, and the hydropower potential could change due to the changing climate in the *** analysis indicates that, though the hydropower generation will increase in the wet season, the plant will face a significant power shortage during the dry season, up to 13.14% from the reference scenario, as a consequence of a 17% reduction of streamflow under an assumption of a 2.9℃ increase in temperature and a 15% decrease in rainfall. Overall, this study showed that hydrological processes are realistically modeled with SWAT and the model can be a useful tool for predicting the impact of climate change.

关键词： SWAT Hydropower generation Climate change Sensitivity analysis Nash-Sutcliffe efficiency(NSE)

Online Adaptive Approximate Optimal Tracking Control with Simplified Dual Approximation Structure for Continuous-time Unknown Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2014年第4期1卷 412-422页

作者： Jing Na guido Herrmann the Faculty of Mechanical and Electrical Engineering Kunming University of Science and Technology the Department of Mechanical Engineering University of Bristol

This paper proposes an online adaptive approximate solution for the infinite-horizon optimal tracking control problem of continuous-time nonlinear systems with unknown *** requirement of the complete knowledge of system dynamics is avoided by employing an adaptive identifier in conjunction with a novel adaptive law, such that the estimated identifier weights converge to a small neighborhood of their ideal *** adaptive steady-state controller is developed to maintain the desired tracking performance at the steady-state, and an adaptive optimal controller is designed to stabilize the tracking error dynamics in an optimal manner. For this purpose, a critic neural network(NN) is utilized to approximate the optimal value function of the Hamilton-Jacobi-Bellman(HJB) equation,which is used in the construction of the optimal controller. The learning of two NNs, i.e., the identifier NN and the critic NN, is continuous and simultaneous by means of a novel adaptive law design methodology based on the parameter estimation *** of the whole system consisting of the identifier NN,the critic NN and the optimal tracking control is guaranteed using Lyapunov theory; convergence to a near-optimal control law is proved. Simulation results exemplify the effectiveness of the proposed method.

关键词： Optimal control Artificial neural networks Convergence Adaptive systems Approximation methods Parameter estimation Steady-state Learning (artificial intelligence) Adaptive control

On-Site Manufacturing in Tip-Growing Cells through RALF1-FERONIA-Mediated Local mRNA Translation

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Molecular Plant 2020年第5期13卷 682-684页

作者： Marjorie Guichard guido Grossmann Centre for Organismal Studies(COS) Heidelberg UniversityIm Neuenheimer Feld 23069120 HeidelbergGermany

Construction sites,particularly in the public sector,are notoriously *** matter how well thought out the construction plan,no matter how rigorously calculated the time schedule,the rate of construction or the time point when the building will ultimately welcome its residents remains largely,*** availability of resources,interactions between contractors,and environmental conditions,as well as control mechanisms and restrictions,form a complex"regulatory network"that governs the construction progress largely independent of the architecfs schedule and accounts for a certain"plasticity"along the way.

关键词： schedule rigorous Site

Peroxisome:the new player in ferroptosis

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Signal Transduction and Targeted Therapy 2020年第1期5卷 221-222页

作者： Daolin Tang guido Kroemer Department of Surgery University of Texas Southwestern Medical CenterDallasTexas 75390USA Center for DAMP Biology University of Texas Southwestern Medical CenterDallasTexas 75390USA Equipe labellisée par la Ligue contre le cancer Universitéde ParisSorbonne UniversitéINSERM U1138Centre de Recherche des CordeliersParisFrance Metabolomics and Cell Biology Platforms Gustave Roussy Cancer Campus94800 VillejuifFrance Pôle de Biologie Hôpital Européen Georges PompidouAP-HP75015 ParisFrance

A recent paper published in Nature by Zou et *** that peroxisomes,membrane-bound oxidative organelles,contribute to ferroptosis through the biosynthesis of plasmalogens for lipid peroxidation(Fig.1).1 These observatio... 详细信息

关键词： peroxidation al death

Lattice Boltzmann Simulation of Free-Surface Temperature Dispersion in Shallow Water Flows

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Advances in Applied Mathematics and Mechanics 2009年第3期1卷 415-437页

作者： Mohammed Seaid guido Thommes School of Engineering University of DurhamSouth RoadDurham DH13LEUK Fraunhofer-Institut fur Techno-und Wirtschaftsmathematik 67663 KaiserslauternGermany

We develop a lattice Boltzmann method for modeling free-surface temperature dispersion in the shallow water *** governing equations are derived from the incompressible Navier-Stokes equations with assumptions of shallow water flows including bed frictions,eddy viscosity,wind shear stresses and Coriolis *** thermal effects are incorporated in the momentum equation by using a Boussinesq *** dispersion of free-surface temperature is modelled by an advection-diffusion *** distribution functions are used in the lattice Boltzmann method to recover the flow and temperature variables using the same lattice *** upwind discretization procedures nor Riemann problem solvers are needed in discretizing the shallow water *** addition,the source terms are straightforwardly included in the model without relying on well-balanced techniques to treat flux gradients and source *** validate the model for a class of problems with known analytical solutions and we also present numerical results for sea-surface temperature distribution in the Strait of Gibraltar.

关键词： Shallow water flows free-surface temperature lattice Boltzmann method advection-diffusion equation strait of Gibraltar

Central role of Yes-associated protein and WW-domain-containing transcriptional co-activator with PDZ-binding motif in pancreatic cancer development

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World Journal of Gastroenterology 2019年第15期25卷 1797-1816页

作者： Enrique Rozengurt guido Eibl Department of Medicine David Geffen School of Medicine University of California at Los Angeles CURE: Digestive Diseases Research Center Department of Surgery David Geffen School of Medicine University of California at Los Angeles

Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive *** genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling *** exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein(YAP) and WW-domaincontaining transcriptional co-activator with PDZ-binding motif(TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.

关键词： Pancreatic cancer Yes-associated protein and WW-domain-containing transcriptional co-activator with PDZ-binding motif Oncogenic Kras Obesity Signaling network and loops

Post-hepatectomy biliary fistula: from risk factors to the role of drain placement and management—still a lot to be answered

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Hepatobiliary Surgery and Nutrition 2019年第4期8卷 417-418页

作者： guido Costa Matteo Donadon guido Torzilli Department of Hepatobiliary and General Surgery Humanitas University & Humanitas Clinical and Research Center – IRCCS Rozzano Milan Italy

Hepatic resection represents the gold-standard treatment for different liver diseases. Among postoperative complications, bile leak remains one of the most common sources of morbidity, which can lead to an increase of hospital stay, need of invasive procedure and potentially death (1). The definition and acknowledge of risk factors for the development of biliary fistula as well as its early detection and optimal management is, in this sense, of crucial importance.

关键词： fistula biliary death

Minimal access liver surgery: from the escalation, to the boundaries, searching for the rules

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Hepatobiliary Surgery and Nutrition 2019年第6期8卷 637-639页

作者： guido Torzilli Division of Hepatobiliary&General Surgery Department of SurgeryHumanitas Research HospitalHumanitas UniversityMilanoItaly

Minimal access liver surgery(MALS),is now routinely performed worldwide,and procedures like limited resections of antero-inferior segments and left lateral sectionectomy could be retained as standard once performed laparoscopically(1).It is a common believe that MALS procedures mean shorter and better postoperative outcome,and essentially more safety compared to the open ***,MALS procedures facing with complex disease presentations are increasingly proposed(2).In this escalation of MALS in the panorama of the surgical offer available for patients with liver tumors open liver surgery(OLS)seems somehow passed *** this setting,the paper of Tong et *** to set clinically based criteria for allowing to foresee the risk of conversion and morbidity once a MALS is planned(3).At least the attempt is worth to be awarded while the results should be validated by means of further studies able to test the scoring system the authors *** sure there is the merit to investigate the burden of MALS,which implies the recognition of a limit and subsequently the need for its precise definition.A definition which,as anything in medicine,could not be considered definitive,since it will probably evolve with expertise and technology as it has been the case in the last 10-15 ***,pointing out the existence of a limit superimposes caution to any effort to get over the burden unless the attempt is based on a solid *** sure,in this sense,the authors have provided an instrument for the surgical community which conveys limits to which any surgeon has to face with.

关键词： routine instrument searching