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FPn-Injective, FPn-Flat Covers and Preenvelopes, and Gorenstein AC-Flat Covers

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Algebra Colloquium 2018年第2期25卷 319-334页

作者： Daniel Bravo sergio estrada Alina Iacob Instituto de Ciencias Fisicas y Matematicas Facultad de Ciencias Universidad Austral de Chile Valdivia Chile Departamento de Matematicas Universidad de Murcia Campus de Espinardo 30100 Murcia Spain Department of Mathematical Sciences Georgia Southern University Statesboro GA 30460 U.S.A

We prove that, for any n 〉 2, the classes of FPn-injective modules and of FPn-flat modules are both covering and preenveloping over any ring R. This includes the case of FP∞-injective and FP∞-flat modules （i.e., absolutely clean and, respectively, level modules）. Then we consider a generalization of the class of （strongly） Gorenstein flat modules, i.e., the （strongly） Gorenstein AC-flat modules （cycles of exact complexes of flat modules that remain exact when tensored with any absolutely clean module）. We prove that some of the properties of Gorenstein fiat modules extend to the class of Gorenstein AC-flat modules; for example, we show that this class is precovering over any ring R. We also show that （as in the case of Gorenstein flat modules） every Gorenstein AC-flat module is a direct summand of a strongly Gorenstein AC-flat module. When R is such that the class of Gorenstein AC-flat modules is closed under extensions, the converse is also true. Moreover, we prove that if the class of Gorenstein AC-flat modules is closed under extensions, then it is covering.

关键词： FPn-injective module FPn-flat module Ding injective module GorensteinAC-flat module

Study of capillary transit time distribution in coherent hemodynamics spectroscopy

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Journal of Innovative Optical Health Sciences 2015年第2期8卷 78-86页

作者： Angelo Sassaroli Jana Kainerstorfer sergio Fantini Department of Biomedical engineering Tufts University 4 Colby StreetMedfordMA 02155USA

A recently proposed analytical hemodynamie modell[***,Neurolmage 85,202-221(2014)]is able to predict the changes of oxy,deoxy,and total hemoglobin concentrations(model outputs)given arbitrary changes in blood flow,blood volume,and rate of oygen consumption(model inputs).One asumption of this model is that the capillary compartment is characterized by a single blood transit *** this work,we have extended the original model by considering a distribution of capillary transit times and we have compared the outputs of both models(original and extended)for the case of sinusoidal input signals at different frequencies,which realizes the new technique of coherent hemodynamics spectroscopy(CHS).For the calculations with the original model,we have used the mean value of the distribution of capillary transit times con-sidered in the extended *** have found that,for distributions of capillary transit times having mean values around 1 s and a standard deviation less than about 45%of the mean value,the original and extended models yield the same CHS spectra(i.e.,model outputs versus fre-quency of ocillation)within typical experimental *** wider capillary transit time dis-tributions,the two models yield different CHS *** assuming that Poiseuille's law is valid in the capillary compartment,we have related the distribution of capillary transit times to the distributions of capillary lengths and capillary speed of blood flow to calculate the average capillary and venous *** have found that,for standard deviations of the capillanry transit time distrilbution that are less than about 80%of the mean value,the average capillary saturation is always larger than the venous *** contrast,the average capillary satu-ration may be less than the venous saturation for wider distributions of the capillary transit times.

关键词： Coherent hemodynamics spectroscopy hermodynamie model near-infrared spectros-copy capillary transit time hemoglobin saturation

On the Foundations of Statistical Mechanics: ergodicity, Many Degrees of Freedom and Inference

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Communications in Theoretical Physics 2014年第10期61卷 469-475页

作者： sergio Chibbaro Lamberto Rondoni Angelo Vulpiani Sorbonne Universités UPMC Univ Paris 06CNRSUMR7190Institut Jean Le Rond d’AlembertF-75005 ParisFrance Kavli Institute for Theoretical Physics China CAS Dip.Scienze Matematiche Politecnico di TorinoC.Duca degli Abruzzi 24TorinoItaly INFN Sezione di TorinoVia P.Giuria 1TorinoItaly Dipartimento di Fisica Università "La Sapienza" RomaItaly ISC-CNR Piazzale A.Moro 2 – 00185 RomaItaly

We review the main aspects of the foundations of statistical mechanics. In particular we explain why many degrees of freedom are necessary, while chaos(in the sense of positive Lyapunov exponents) is only marginally r... 详细信息

关键词： ergodic hypothesis chaos emergent properties statical inference

Colchicine reduces procollagen Ⅲ and increases pseudocholinesterase in chronic liver disease

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World Journal of Gastroenterology 2010年第23期16卷 2889-2894页

作者： sergio Muntoni Marcos Rojkind Sandro Muntoni Centre for Metabolic Diseases and Atherosclerosis The Metabolic Diseases and their Complications Association The George Washington University Medical Center Department of Toxicology Unit of Oncology and Molecular PathologyUniversity of Cagliari Medical School

AIM:To test whether colchicine would be an effective antif ibrotic agent for treatment of chronic liver diseases in patients who could not be treated with α-***:Seventy-four patients(46 males,28 females) aged 40-66 years(mean 53±13 years) participated in the *** patients were affected by chronic liver diseases with cirrhosis which was proven histologically(n=58);by chronic active hepatitis C(n=4),chronic active hepatitis B(n=2),and chronic persistent hepatitis C(n=6).In the four patients lacking histology,cirrhosis was diagnosed from anamnesis,serum laboratory tests,esophageal varices and *** were assigned to colchicine(1 mg/d) or standard treatment as control in a randomized,double-blind trial,and followed for 4.4 years with clinical and laboratory ***:Survival at the end of the study was 94.6% in the colchicine group and 78.4% in the control group(P=0.001).Serum N-terminal peptide of type Ⅲ procollagen levels fell from 34.0 to 18.3 ng/mL(P=0.0001),and pseudocholinesterase levels rose from 4.900 to 5.610 mU/mL(P=0.0001) in the colchicine group,while no signif icant change was seen in *** results were obtained in patients with chronic hepatitis C and in alcoholic ***:Colchicine is an effective and safe antifibrotic drug for long-term treatment of chronic liver disease in which fi brosis progresses towards cirrhosis.

关键词： Chronic liver disease Colchicine Liver cirrhosis Liver fibrosis Type Ⅲ procollagen peptide

Inequalities for the extended Best Polynomial Approximation Operator in Orlicz Spaces

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Acta Mathematica Sinica,english Series 2019年第2期35卷 185-203页

作者： Sonia ACINAS sergio FAVIeR Felipe ZO Departamento de Matemática Facultad de Ciencias y Exactas NaturalesUniversidad Nacional de La Pampa Instituto de Matemática Aplicada San Luis IMASLUniversidad Nacional de San Luis and CONICET Departamento de Matemática Universidad Nacional de San Luis

In this paper we pursue the study of the best approximation operator extended from L~Φ to L~φ, where φ denotes the derivative of the function Φ. We get pointwise convergence for the coefficients of the extended best approximation polynomials for a wide class of function f, closely related to the Calder′on–Zygmund class t_m^p(x) which had been introduced in 1961. We also obtain weak and strong type inequalities for a maximal operator related to the extended best polynomial approximation and a norm convergence result for the coefficients is derived. In most of these results, we have to consider Matuszewska–Orlicz indices for the function φ.

关键词： Orlicz spaces extended best polynomial approximation pointwise and norm convergence weak and strong type inequalities Orlicz indices

Rhynchophorus ferrugineus attack affects a group of compounds rather than rearranging Phoenix canariensis metabolic pathways

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Journal of Integrative Plant Biology 2016年第4期58卷 388-396页

作者： Antonio Giovino Federico Martinelli sergio Saia Consiglio per la Ricerca in Agricoltura e l'analisi dell'economia agraria(CReA) Unita di ricerca per il recupero e la valorizzazione delle Specie Floricole Mediterranee(CREA-SFM)90011 Bagheria(PA)Italy Dipartimento di Scienze Agrarie e Forestali(SAF) University of PalermoViale delle ScienzeEdif.490128 PalermoItaly Istituto euromediterraneo di Scienza e Tecnologia(IeMeST) Via E.Amari 12390139 PalermoItaly

The red palm weevil（RPW; Rhynchophorus ferrugineus） is spreading worldwide and severely harming many palm species. However, most studies on RPW focused on insect biology, and little information is available about the plant response to the attack. In the present experiment, we used metabolomics to study the alteration of the leaf metabolome of Phoenix canariensis at initial（1^（st） stage） or advanced（2^（nd） stage）attack by RPW compared with healthy（unattacked） *** leaf metabolome significantly varied among treatments. At the 1^（st） stage of attack, plants showed a reprogramming of carbohydrate and organic acid metabolism; in contrast, peptides and lipid metabolic pathways underwent more changes during the 2^（nd） than 1^（st） stage of attack. enrichment metabolomics analysis indicated that RPW attack mostly affected a particular group of compounds rather than rearranging plant metabolic pathways. Some compounds selectively affected during the 1^（st） rather than 2^（nd） stage（e.g. phenylalanine; tryptophan; cellobiose;xylose; quinate; xylonite; idonate; and iso-threonate; cellobiotol and arbutine） are upstream events in the phenylpropanoid,terpenoid and alkaloid biosynthesis. These compounds could be designated as potential markers of initial RPW attack. However,further investigation is needed to determine efficient early screening methods of RPW attack based on the concentrations of these molecules.

关键词： early detection Mediterranean environment metabolomics palms plant borer

Glial regenerative response in the imaginal discs of Drosophila melanogaster

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Neural Regeneration Research 2023年第1期18卷 109-110页

作者： sergio B.Velarde Antonio Baonza Centro de Biología Molecular“Severo Ochoa” CSIC/UAMMadridSpain

Glial cells play a key role during nervous system development and actively participate in all the cellular processes involved in maintaining its structural robustness and functional *** response to neuronal damage,glial cells proliferate,migrate to the injured region and change their morphology,function,and behavior(Gallo and Deneen,2014;Kato et al.,2018).This glial regenerative response is associated with the repairing function of these cells and is found across species,suggesting that it may reflect a common underlying genetic mechanism(Kato et al.,2018).

关键词： damage migrate

Windmills： Ancestors of the wind power generation

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Frontiers of Mechanical engineering 2017年第3期12卷 389-396页

作者： Cesare ROSSI Flavio RUSSO sergio SAVINO Department of Industrial engineering University of Naples "Federico Ⅱ" via Claudio Naples 80125 Italy Consultant of Ufficio Storico Stato Maggiore esercito Torre Del Greco 80059 Italy

A brief description of the windmills from the second millennium BC to the Renaissance is presented. This survey is a part of several studies conducted by the authors on technology in the ancient world. The windmills are the first motor, other than human muscles, and are the ancestors of the modem wind turbines. Some authors＇ virtual reconstructions of old windmills are also presented. The paper shows that the operating principle of many modem machines had already been conceived in the ancient times by using a technology that was more advanced than expected, but with two main differences, as follows： Similar tasks were accomplished by using much less energy; and the environmental impact was nil or very low. Modem designers should sometimes consider simplicity rather than the use of a large amount of energy.

关键词： windmills ancient machines history of windmill

Analysis of suitable geometrical parameters for designing a tendon-driven under-actuated mechanical finger

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Frontiers of Mechanical engineering 2016年第2期11卷 184-194页

作者： Francesco PeNTA Cesare ROSSI sergio SAVINO Department of Industrial engineering University of Naples 'FedericoII' Naples 80125 Italy

This study aims to optimize the geometrical parameters of an under-actuated mechanical finger by conducting a theoretical analysis of these parameters. The finger is actuated by a flexion tendon and an extension tendon. The considered parameters are the tendon guide positions with respect to the hinges. By applying such an optimization, the correct kinematical and dynamical behavior of the closing cycle of the finger can be obtained. The results of this study are useful for avoiding the snap- through and the single joint hyperflexion, which are the two breakdowns most frequently observed during experi- mentation on prototypes. Diagrams are established to identify the optimum values for the tendon guides position of a finger with specified dimensions. The findings of this study can serve as guide for future finger design.

关键词： tendon-driven fingers mechanical fingerdesign under-actuated mechanical systems