检索结果-南通市图书馆

Sequential algorithms combining non-invasive markers and biopsy for the assessment of liver fibrosis in chronic hepatitis B

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2007年第4期13卷 525-531页

作者： Giada Sebastiani Alessandro Vario Maria guido Alfredo Alberti Depart-ment of Clinical and Experimental Medicine University of Pado-va Padova Italy Department of Oncological and Surgical Sciences University of Padova Padova Italy

AIM： To assess the performance of several noninvasive markers and of our recently proposed stepwise combination algorithms to diagnose significant fibrosis （F ≥ 2 by METAVIR） and cirrhosis （F4 by METAVIR） in chronic hepatitis B （CHB）.METHODS： One hundred and ten consecutive patients （80 males, 30 females, mean age： 42.6 ± 11.3） with CHB undergoing diagnostic liver biopsy were included. AST-to-Platelet ratio （APRI）, Forns＇ index, AST-to-ALT Ratio, Goteborg University Cirrhosis Index （GUCD, Hui＇s model and Fibrotest were measured on the day of liver biopsy. The performance of these methods and of sequential algorithms combining Fibrotest, APRI and biopsy was defined by positive （PPV） and negative （NPV） predictive values, accuracy and area under the curve （AUC）. RESULTS： PPV for significant fibrosis was excellent （100%） with Forns and high （〉 92%） with APR1, GUCI, Fibrotest and Hui. However, significant fibrosis could not be excluded by any marker （NPV 〈 65%）. Fibretest had the best PPV and NPV for cirrhosis （87% and 90%, respectively）. Fibrotest showed the best AUC for both significant fibrosis and cirrhosis （0.85 and 0.76, respectively）. Stepwise combination algorithms of APR1, Fibrotest and biopsy showed excellent performance （0.96 AUC, 100% NPV） for significant fibrosis and 0.95 AUC, 98% NPV for cirrhosis, with 50%-80% reduced need for liver biopsy. CONCLUSION： In CHB sequential combination of APRI, Fibrotest and liver biopsy greatly improves the diagnostic performance of the single non-invasive markers. Need for liver biopsy is reduced by 50%-80% but cannot be completely avoided. Non-invasive markers and biopsy should be considered as agonists and not antagonists towards the common goal of estimating liver fibrosis.

关键词： Chronic hepatitis B Hepatic fibrosis Liverbiopsy Non-invasive markers Stepwise combinationalgorithms

Mature versus emerging technologies for CO2 capture in power plants： Key open issues in post-combustion amine scrubbing and in chemical looping combustion

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 Chemical Science and Engineering 2018年第2期12卷 315-325页

作者： Giorgia De guido Matteo Compagnoni Laura A. Pellegrini Ilenia Rossetti Department of Chemistry Materials and Chemical Engineering "Giulio Natta" Politecnico di Milano Piazza Leonardo da Vinci 32 20133 MilanItaly Department of Chemistry Universita degli Studi di Milano INSTM Unit Milano-Universita and CNR-ISTM Via Camillo Golgi 19 20133 Milan Italy

Carbon capture and storage （CCS） have acquired an increasing importance in the debate on global wanning as a mean to decrease the environmental impact of energy conversion technologies, by capturing the CO2 produced from the use of fossil fuels in electricity generation and industrial processes. In this respect, post-combustion systems have received great attention as a possible near-term CO2 capture technology that can be retrofitted to existing power plants. This capture technology is, however, energy-intensive and results in large equipment sizes because of the large volumes of the flue gas to be treated. To cope with the demerits of other CCS technologies, the chemical looping combustion （CLC） process has been recently considered as a solution for CO2 separation. It is typically referred to as a technology without energy penalty. Indeed, in CLC the fuel and the combustion air are never mixed and the gases from the oxidation of the fuel （i.e., CO2 and H2O） leave the system as a separate stream and can be separated by condensation of H2O without any loss of energy. The key issue for the CLC process is to find a suitable oxygen carrier, which provides the fuel with the activated oxygen needed for combustion. The aim of this work is to explore the feasibility of using perovskites as oxygen carriers in CLC and to consider the possible advantages with respect to the scrubbing process with amines, a mature post-combustion technology for CO2 separation.

关键词： CO2 capture monoethanolamine chemical looping combustion oxygen carder perovskites

Effects of calibration process on the simulation of rear-end conflicts at roundabouts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2019年第2期6卷 175-184页

作者： Vincenzo Gallelli Giuseppe guido Alessandro Vitale Rosolino Vaiana Department of Civil Engineering University of Calabria

A methodology for calibrating and validating VISSIM simulation model is presented that allows to replicate the observed vehicles conflicts. A roundabout case study has been selected to test the usefulness of a combined approach of VISSIM simulation package and the surrogate safety assessment model(SSAM) for providing reliable estimates of traffic conflicts. Safety performance has been assessed from the field by video-recording vehicle interactions at the roundabout, and then expressed in terms of time to collision(TTC)*** proposed calibration procedure has been performed by a multistage methodology involving microscopic drivers' car following behavior parameters to enhance the correlation between observed and simulated queue lengths at the roundabout's entries. The calibration procedure is based on a statistical screening of inputs leading to a linear expression relating significant parameters to the queue length. The best estimates of the model's parameters have been determined using a genetic algorithm *** spatial distribution of the rear-end conflicts and the TTC values determined by SSAM have been finally compared with the observed ones to analyze the capability of the model of replicating rear-end *** results suggest to this calibration procedure impacts positively on the estimate of the safety performance measures obtained through the simulation *** the good results in the evaluation of the model's accuracy, the simulation seems to fail in reproducing the traffic phenomena linked to unusual driving behavior, and therefore it is not able to replicate forced drivers' maneuvers that can lead to a conflict situation.

关键词： Simulation Safety performance Unmanned aerial vehicle Roundabouts Traffic conflicts

Insight into the interaction of inhaled corticosteroids with human serum albumin: A spectroscopic-based study

在线全文

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2018年第1期8卷 37-44页

作者： Carlotta Pontremoli Nadia Barbero guido Viscardi Sonja Visentin Department of Applied Science and Technology (DISAT) Politecnico of Torino Department of Chemistry and NIS Interdepartmental Centre University of Torino Molecular Biotechnology and Health Sciences Department University of Torino

It is well known that the safety and efficacy profile of an inhaled cortocosteroid(ICS) is influenced by the pharmacokinetic properties and associated pharmacodynamic effects of the drug. Freely circulating,protein unbound, and active ICS can cause systemic adverse effects. Therefore, a detailed investigation of drug-protein interaction could be of great interest to understand the pharmacokinetic behaviour of corticosteroids and for the design of new analogues with effective pharmacological properties. In the present work, the interaction between some corticosteroids and human serum albumin(HSA) has been studied by spectroscopic approaches. UV–Vis spectroscopy confirmed that all the investigated corticosteroids can bind to HSA forming a protein-drug complex. The intrinsic fluorescence of HSA was quenched by all the investigated drugs, which was rationalized in terms of a static quenching mechanism. The thermodynamic parameters determined by the Van't Hoff analysis of the binding constants(negative ΔH and ΔS values) clearly indicate thathydrogen bonds and van der Waals forces play a major role in the binding process between albumin and betamethasone, flunisolide and prednisolone, while hydrophobic forces may play a major role in stabilizing albumin-triamcinolone complexes.

关键词： Human serum albumin Inhaled corticosteroids Fluorescence spectroscopy Fluorescence resonance energy transfer(FRET)

Echocardiography and impedance cardiography as determinants of successful slow levosimendan infusion in advanced older heart failure patients

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2021年第12期18卷 1058-1062页

作者： Gaetano Ruocco guido Pastorini Mauro Feola Cardiology Unit Riuniti of Valdichiana HospitalUSL-SUD-EST ToscanaMontepulcianoSienaItaly Cardiology Unit Regina Montis Regalis HospitalASL-CN1MondovìCuneoItaly

Despite new therapeutic options,patients with heart failure(HF)still progress to advanced *** particular,patients who developed a severe left ventricular(LV)systolic and/or diastolic dysfunction with higher degree of NYHA class,recurrent hospitalizations for HF and showing a severe impairment of exercise capacity were defined as“advanced HF”.[1]Levosimendan was recently approved in order to treat patients hospitalized for acute decompensated HF(ADHF)with severe systolic *** pharmacolo-gical effects of levosimendan consists of inotropy,vasodilatation and cardioprotection increasing of calcium sensitivity.[2]These effects should be mon-itored with echocardiography.[3]In particular,in ad-vanced HF patients,levosimendan showed positive effects in reducing mortality and three months hos-pitalization;about quality of life and symptoms im-provement,levosimendan showed contrasting ef-fect among the studies on advanced HF patients available.

关键词： patients infusion mortality

Synthesis of Fractional-order PI Controllers and Fractional-order Filters for Industrial Electrical Drives

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 58-69页

作者： Paolo Lino guido Maione Silvio Stasi Fabrizio Padula Antonio Visioli IEEE Dipartimento di Ingegneria Elettrica e dell’Informazione Politecnico di Bari Department of Mathematics and Statistics Curtin University Department of Mechanical and Industrial Engineering University of Brescia

This paper introduces an electrical drives control architecture combining a fractional-order controller and a setpoint pre-filter. The former is based on a fractional-order proportional-integral(PI) unit, with a non-integer order integral action, while the latter can be of integer or non-integer type. To satisfy robustness and dynamic performance specifications, the feedback controller is designed by a loop-shaping technique in the frequency domain. In particular, optimality of the feedback system is pursued to achieve input-output tracking. The setpoint pre-filter is designed by a dynamic inversion technique minimizing the difference between the ideal synthesized command signal(i.e., a smooth monotonic response) and the prefilter step response. Experimental tests validate the methodology and compare the performance of the proposed architecture with well-established control schemes that employ the classical PIbased symmetrical optimum method with a smoothing pre-filter.

关键词： Dynamic inversion electrical drives fractionalorder PI controller loop-shaping set-point pre-filter

The urgency of Agriculture Green Development

在线全文

学校读者我要写书评

暂无评论

Frontiers of Agricultural Science and Engineering 2020年第1期7卷 108-109页

作者： guido SCHMIDT-TRAUB UN Sustainable Development Solutions Network(SDSN) New YorkNY 10115USA

As Shen et *** other authors lay out convincingly in this special issue,Agriculture Green Development(AGD)is an urgent imperative for China and the ***,high-productivity agriculture is vital for food security and economic development,particularly in a country like China,which comprises 20%of the world’s population but only has 8%of the arable land.

关键词： Agriculture Development land

Effects of external temperature and dead volume on laboratory measurements of pore pressure and injected volume in a rock fracture

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1461-1469页

作者： Yinlin Ji Christian Kluge Hannes Hofmann guido Blöcher Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesPotsdam14473Germany State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou221116China

The accurate evaluation of pore pressure and injected volume is crucial for the laboratory characterization of hydromechanical responses of rock fractures. This study reports a series of laboratory experiments to systematically demonstrate the effects of external temperature and dead volume on laboratory measurements of pore pressure and injected volume in a rock fracture. We characterize the hydraulic aperture of the fracture as a function of effective normal stress using the exponential aperture *** model is then employed to predict the pore pressure change and injected volume in the fracture without the influences of external temperature and dead volume. The external temperature changes in the cyclic loading test due to the Joule-Thompson effect for fluids. The effect of external temperature on pore pressure change in the fracture can be well explained by thermal pressurization of fluids. Our results also show that the external dead volume can significantly lower the pore pressure change in the fracture during the cyclic loading test under undrained conditions. The injected volume can also be substantially enlarged due to the external dead volume in a typical pore pressure system. Internal measurement of the pore pressure in the fracture using a fiber optic sensor cannot exclude the influences of external temperature and dead volume, primarily because of the good hydraulic communication between the fracture and pore pressure system. This study suggests that the effects of external temperature and dead volume on pore pressure response and injected volume should be evaluated for accurate laboratory characterization and inter-laboratory comparison.

关键词： Fracture aperture Thermal pressurization External dead volume Pressure attenuation Injected volume Fiber optic sensor

Self-assembly of highly ordered DNA origami lattices at solid-liquid interfaces by controlling cation binding and exchange

在线全文

学校读者我要写书评

暂无评论

Nano Research 2020年第11期13卷 3142-3150页

作者： Yang Xin Salvador Martinez Rivadeneira guido Grundmeier Mario Castro Adrian Keller Technical and Macromolecular Chemistry Paderborn UniversityPaderborn33098Germany Grupo Interdisciplinar de Sistemas Complejos and Instituto de Investigación Tecnológica Universidad Pontificia Comillas de MadridMadrid28015Spain

The surface-assisted hierarchical self-assembly of DNA origami lattices represents a versatile and straightforward method for the organization of functional nanoscale objects such as proteins and ***,we demonstrate that controlling the binding and exchange of different monovalent and divalent cation species at the DNA-mica interface enables the self-assembly of highly ordered DNA origami lattices on mica *** development of lattice quality and order is quantified by a detailed topological analysis of high-speed atomic force microscopy(HS-AFM)*** find that lattice formation and quality strongly depend on the monovalent cation ***^(+)is more effective than Li^(+)and K^(+)in facilitating the assembly of high-quality DNA origami lattices,because it is replacing the divalent cations at their binding sites in the DNA backbone more *** regard to divalent cations,Ca^(2+)can be displaced more easily from the backbone phosphates than Mg^(2+)and is thus superior in guiding lattice *** independently adjusting incubation time,DNA origami concentration,and cation species,we thus obtain a highly ordered DNA origami lattice with an unprecedented normalized correlation length of *** the correlation length,we use computer vision algorithms to compute the time course of different topological observables that,overall,demonstrate that replacing MgCl_(2) by CaCl_(2) enables the synthesis of DNA origami lattices with drastically increased lattice order.

关键词： DNA origami self-assembly lattice formation high-speed atomic force microscopy topological analysis