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Plasma Science and Technology 2024年第11期26卷 65-70页

作者： Ricardo FARENGO pablo L GARCÍA-MARTÍNEZ Hugo E FERRARI Centro Atómico Bariloche Comisión Nacional de Energía AtómicaBariloche 8400Argentina Instituto Balseiro Universidad Nacional de CuyoBariloche 8400Argentina CONICET CCT-Patagonia Norte Bariloche 8400Argentina

A simple and fast method to calculate the coil currents and the external poloidal flux and magnetic field consistent with a given internal magnetohydrodynamic(MHD) equilibrium and coil geometry is presented. The constrained optimization technique employed allows to fix the exact position of the X-points. The external poloidal flux and field are calculated using Green's functions expressed in terms of elliptic integrals that are calculated using a fast and accurate *** calculation can be limited to the region between the plasma and the device wall. An example for a double null configuration is presented.

关键词： MHD equilibrium Green's functions tokamak

Hölder,Sobolev,weak-type and BMO estimates in mixed-norm with weights for parabolic equations

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Science China Mathematics 2021年第1期64卷 129-154页

作者： pablo Raúl Stinga José L.Torrea Department of Mathematics Iowa State UniversityAmesIA50011USA Departamento de Matemáticas Universidad Autónoma de MadridMadrid28049Spain

We prove weighted mixed-norm Lqt(W2,px)and Lqt(C2,αx)estimates for 10,x∈Rn.x∈Rn,The coefficients a(t)=(aij(t))are just bounded,measurable,symmetric and uniformly ***,we show strong,weak type and BMO-Sobolev estimates with parabolic Muckenhoupt *** is quite remarkable that most of our results are new even for the classical heat equation∂tu−Δu+u=f.

关键词： Calderón-Zygmund parabolic singular integrals weak type and BMO estimates representation formulas parabolic equations mixed-norm Sobolev and Schauder estimates

Root and leaf functional trait relations in Poaceae species: implications of differing resource- acquisition strategies

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Journal of Plant Ecology 2013年第3期6卷 211-219页

作者： Florian Fort Claire Jouany pablo Cruz INRA UMR 1248 AGIRCentre de recherche de ToulouseCS 5262731326 Castanet-TolosanCedexFrance

Aims root systems play an essential role in grassland functioning in both acquisition and storage of ***,root functional traits have not received as much attention as those measured on above-ground organs,and little is known about their *** objec-tives were to test whether morphological and root system traits allowed identification of grass species’functional strategies and to determine whether a relation exists between above-and below-ground *** Functional traits of root tissues(specific root length,diameter,tissue density and nitrogen concentration),whole root systems(root mass,root length density,root mass percentage below a depth of 20 cm and fine root%)and two major leaf traits(specific leaf area and leaf dry matter content)were determined under field conditions and their rela-tions were analysed in eleven perennial temperate Poaceae *** Findings Canonical correspondence analysis along axis 1 revealed a gra-dient of species,from those with deep,dense and coarse root systems with a large root mass to those with shallow root sys-tems,thin roots and high specific root length;this suggests strong correlations among root *** between specific root length and specific leaf area reveal two groups of species,which probably indicates different drought-tolerance *** trait syndromes enable ranking grasses along a gradient from conservative-strategy species(from stressful habitats),which display a deep and coarse root system,to acquisitive species(from rich and moist meadows),which display a shallow and thin root *** both types display similar above-ground strategies,drought-tolerant species have lower specific root lengths than drought-sensitive species,revealing more conservative root strategies.

关键词： root functional trait functional group grasses root ecology below-ground strategy

Beneficial effects of naringenin in liver diseases: Molecular mechanisms

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World Journal of Gastroenterology 2018年第16期24卷 1679-1707页

作者： Erika Hernández-Aquino pablo Muriel Laboratory of Experimental Hepatology Department of Pharmacology

Liver diseases are caused by different etiological agents, mainly alcohol consumption, viruses, drug intoxication or malnutrition. Frequently, liver diseases are initiated by oxidative stress and inflammation that lead to the excessive production of extracellular matrix(ECM), followed by a progression to fibrosis, cirrhosis and hepatocellular carcinoma(HCC). It has been reported that some natural products display hepatoprotective properties. Naringenin is a flavonoid with antioxidant, antifibrogenic, anti-inflammatory and anticancer properties that is capable of preventing liver damage caused by different agents. The main protective effects of naringenin in liver diseases are the inhibition of oxidative stress, transforming growth factor(TGF-β) pathway and the prevention of the transdifferentiation of hepatic stellate cells(HSC), leading to decreased collagen synthesis. Other effects include the inhibition of the mitogen activated protein kinase(MAPK), toll-like receptor(TLR) and TGF-β non-canonical pathways, the inhibition of which further results in a strong reduction in ECM synthesis and deposition. In addition, naringenin has shown beneficial effects on nonalcoholic fatty liver disease(NAFLD) through the regulation of lipid metabolism, modulating the synthesis and oxidation of lipids and cholesterol. Moreover, naringenin protects from HCC, since it inhibits growth factors such as TGF-β and vascular endothelial growth factor(VEGF), inducing apoptosis and regulating MAPK pathways. Naringenin is safe and acts by targeting multiple proteins. However, it possesses low bioavailability and high intestinal metabolism. In this regard, formulations, such as nanoparticles or liposomes, have been developed to improve naringenin bioavailability. We conclude that naringenin should be considered in the future as an important candidate in the treatment of different liver diseases.

关键词： Naringenin transforming growth factor liver fibrosis MAPKs CCl4 flavonoids JNK hepatic stellate cells cirrhosis Smads α-SMA

An ontology model to represent aquaponics 4.0 system’s knowledge

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Information Processing in Agriculture 2022年第4期9卷 514-532页

作者： Rabiya Abbasi pablo Martinez Rafiq Ahmad Aquaponics 4.0 Learning Factory(AllFactory) Department of Mechanical EngineeringUniversity of Alberta9211116 St.EdmontonAB T6G 2G8Canada

Aquaponics,one of the vertical farming methods,is a combination of aquaculture and *** enhance the production capabilities of the aquaponics system and maxi-mize crop yield on a commercial level,integration of Industry 4.0 technologies is *** 4.0 is a strategic initiative characterized by the fusion of emerging technologies such as big data and analytics,internet of things,robotics,cloud computing,and artificial *** realization of aquaponics 4.0,however,requires an efficient flow and inte-gration of data due to the presence of complex biological processes.A key challenge in this essence is to deal with the semantic heterogeneity of multiple data *** ontology that is regarded as one of the normative tools solves the semantic interoperation problem by describing,extracting,and sharing the domains’*** the field of agriculture,several ontologies are developed for the soil-based farming methods,but so far,no attempt has been made to represent the knowledge of the aquaponics 4.0 system in the form of an ontology ***,this study proposes a unified ontology model,AquaONT,to rep-resent and store the essential knowledge of an aquaponics 4.0 *** ontology pro-vides a mechanism for sharing and reusing the aquaponics 4.0 system’s knowledge to solve the semantic interoperation *** is built from indoor vertical farming termi-nologies and is validated and implemented by considering experimental test cases related to environmental parameters,design configuration,and product *** proposed ontology model will help vertical farm practitioners with more transparent decision-making regarding crop production,product quality,and facility layout of the aquaponics *** future work,a decision support system will be developed using this ontology model and artificial intelligence techniques for autonomous data-driven decisions.

关键词： Aquaponics 4.0 Industry 4.0 Ontology modeling Knowledge modeling Decision support system

Reaction mechanism of hydrogen activation by frustrated Lewis pairs

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Green Energy & Environment 2019年第1期4卷 20-28页

作者： Lei Liu Binit Lukose pablo Jaque Bernd Ensing Department of Physics & Earth Sciences Jacobs University Max Planck Institute for Polymer Research School of Electrical and Computer Engineering Boston University Department of Organic and Physical Chemistry Faculty of Chemical and Pharmaceutical Sciences University of Chile Van't Hoff Institute for Molecular Sciences University of Amsterdam

Typically, a Lewis acid and a Lewis base can react with each other and form a classical Lewis adduct. The neutralization reaction can however be prevented by ligating the acid and base with bulky substituents and the resulting complex is known as a "frustrated Lewis pair"(FLP). Since the Lewis acid and base reactivity remains in the formed complex, FLPs can display interesting chemical activities, with promising applications in catalysis. For example, FLPs were shown to function as the first metal-free catalyst for molecular hydrogen activation. This, and other recent applications of FLPs, have opened a new thriving research field. In this short-review, we recapitulate the computational and experimental studies of the H_2 activation by FLPs. We discuss the thus-far uncovered mechanistic aspects, including pre-organization of FLPs,the reaction paths for the activation, the polarization of He H bond and other factors affecting the reactivity. We aim to provide a rather complete mechanistic picture of the H_2 activation by FLPs, which has been under debate for decades since the first discovery of FLPs. This review is meant as a starting point for future studies and a guideline for industrial applications.

关键词： Frustrated Lewis pairs Hydrogen activation Reaction mechanisms Density functional theory Molecular dynamics simulations

Toward a History of Cross-Cultural Written Symbols

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Language and Semiotic Studies 2017年第1期3卷 62-78页

作者： Javier Terrado-pablo University of Lleida Spain

It is our assumption that the goal of primitive written symbols was to create suprasubjective representations. We feel that this has continued to be the case throughout the course of history. In an increasingly globalised world, this goal seems even more evident, and we could highlight that symbolic representations tend to be supraregional, supranational, supracultural, and supraideological. Arabic, Chinese, and Suzhou numerals are nowadays restricted to specific uses and regions. Instead, Hindu-Arabic numerals, widely spread by modern computers, are commonly used everywhere. Millions of people know the meaning of symbols such as 2, 3, 4, 5, =, ≠, ≥,√, and ∞. Almost everybody is able to recognize the usual iconic signs that mean ‘disabled person' or ‘smoking is forbidden'. And in spite of its importance in contemporary society, a project devoted to the study of the origins, spreading, and evolution of those symbols is still lacking. The aim of our paper is to point out the theoretical and methodological assumptions upon which a history of cross-cultural written symbols should be undertaken. In this essay we consider the opportunity to study the history of written symbols a chapter in the evolution of mankind marked by a twofold1 process: on the one side, the divergence of symbolic systems all around the world in past times, and on the other, the symptoms of a convergence of these systems at present, or we might say, the will of convergence toward new, unifi ed systems.

关键词： semiotics symbols written systems evolution cross-cultural history

Effects of absolute fasting on reproduction and survival of the invasive apple snail Pomacea canaliculata in its native range

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Current Zoology 2016年第4期62卷 369-375页

作者： Nicolas E. TAMBURI pablo R. MARTIN INBIOSUR (UNS-CONICET) Universidad Nacional del Sur Departamento de Biologla Bioquimica y Farmacia San Juan 670 8000 Bahia Blanca Argentina

A South American freshwater gastropod, the apple snail Pomacea canaliculata, has become a driver of ecosystemic changes in wetlands and an important rice pest after its introduction to various parts of the world, mainly Asia. The objective of this study was to study the effect of an abrupt interruption in food availability in the short term （up to 4 weeks） and long term （up to 8 months） on survival and re- productive activity. The main results indicate that short-term fasting mainly affects the survival of males, but only when they are raised together with females, probably due to a greater mate-searching activity that increases mortality in the individuals with lower reserves. The number of copulating snails or egg-laying females shows an abrupt drop when fasting and a rapid recovery after the food supply is restored. The strategy of discontinuing reproductive activity prioritizes energy conservation for the survival of the females. Interpopulation variation in resistance to starvation was observed in adults, which can be explained to some extent by the food availability that they experienced in their natural environment. No interpopulational differences in survival were seen in hatchlings. The mean maximum values of survival under starvation were 52.6 days in hatchlings and the 3.3% of adults survive over than 200 days, which may be a relevant trait in dispersal and establishment in new habitats.

关键词： GASTROPODA POMACEA canaliculata WETLANDS STARVATION ENERGY conservation

Predator-induced physiological responses in tadpoles challenged with herbicide pollution

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Current Zoology 2013年第4期59卷 475-484页

作者： pablo BURRACO Lidia Jimenez DUARTE Ivan GOMEZ-MESTRE Ecology Evolution and Development Group Estaci6n Biol6gica de Dofiana (EBD-CSIC) E-41092 Seville Spain Av. Las Ciencias 4 2℃ 41020 Sevilla Spain

Predators induce plastic responses in multiple prey taxa, ranging from morphological to behavioral or physiological changes. In amphibians, tadpoles activate plastic responses to reduce predation risk by reducing their activity rate and altering their morphology, specifically tail depth and pigmentation. Furthermore, there is now evidence that tadpoles＇ defenses are modi- fied when predators combine with other stressful factors such as pollutants or competitors, but our knowledge on the physiologi- cal responses underlying these responses is still scarce. Here we study physiological responses in Pelobates cultripes tadpoles exposed to a natural predator （larvae of the aquatic beetle Dytiscus circumflexus）, non-lethal concentrations of herbicide （gly- phosate, 0.5 mg/L and 1.0 mg/L） or both factors combined. We measured corticosterone levels, standard metabolic rate, oxidative damage （TBARS） and activity of antioxidant enzymes, and immune response （via leukocyte count）. Tadpoles reduced their corti- costerone concentration by ca. 24% in the presence of predator cues, whereas corticosterone did not change in the presence of glyphosate. Two enzymes involved in antioxidant response also decreased in the presence of predators （14.7% and 13.2% respec- tively） but not to glyphosate. Herbicide, however, increased the number of neutrophils and reduced that of lymphocytes, and had an interaction effect with predator presence. Standard metabolic rate did not vary across treatments in our experiment. Thus we show a marked physiological response to the presence of predators but little evidence for interaction between predators and low levels of herbicide. Multiple assessment of the physiological state of animals is important to understand the basis and conse- quences ofphenotypic plasticity

关键词： Inducible defenses Physiological responses Corticosterone Glyphosate Spadefoot toads Oxidative stress

Estrogen rapid effects:a window of opportunity for the aging brain?

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Neural Regeneration Research 2022年第8期17卷 1629-1632页

作者： Ivanny Marchant Jana Stojanova Lilian Acevedo pablo Olivero Laboratorio de Modelamiento en Medicina Escuela de MedicinaUniversidad de ValparaísoViña del MarChile Interdisciplinary Centre for Health Studies(CIESAL) Universidad de ValparaísoViña del MarChile Servicio de Neurología Hospital Carlos van Buren ValparaísoChile Laboratorio de Estructura y Función Celular Escuela de MedicinaFacultad de MedicinaUniversidad de ValparaísoValparaísoChile Centro Interoperativo en Ciencias Odontológicas y Médicas Universidad de ValparaísoValparaísoChile

Estrogen produces several beneficial effects in healthy neurological tissues and exhibits cardioprotective *** therapy has been widely used to treat menopausal estrogen deficiency for more than 80 *** high initial expectations of cardioprotective effects,there has been substantial distrust following important randomized clinical trials,such as the Women’s Health ***,the timing of treatment in relation to the onset of menopause came under consideration and led to the proposal of the timing hypothesis,that early initial treatment is important,and benefits are lost as the timing since menopause becomes *** analyses of the Women’s Health Initiative data,together with more recent data from randomized and observational trials,consistently show reductions in coronary heart disease and mortality in younger menopausal *** cognitive function,the timing hypothesis is consistent with observations from basic and animal *** is some clinical evidence to support the benefits of hormonal therapy in this context,though skepticism remains due to the paucity of clinical trials of substantial length in younger menopausal *** is likely that the effects of estrogens on cognitive performance are due to rapid mechanisms,including mechanisms that influence Ca2+homeostasis dynamics,provide protection in a hostile environment and reduce inflammatory signals from neural *** the future,inflammatory profiles accounting for early signs of pathological inflammation might help identify the‘window of opportunity’to use estrogen therapy for successful cognitive protection.

关键词： aging cardiovascular prevention cognitive function estrogen hormone treatment inflammaging rapid effects timing hypothesis TRPV1 window of opportunity