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International Journal of Digital Earth 2023年第1期16卷 3810-3837页

作者： Nicola Montaldo Andrea Gaspa roberto Corona Dipartimento di Ingegneria civile ambientale e architetturaUniversita di CagliariCagliariItaly

Periodic observations of vegetation index,such as the normalized difference vegetation index(NDVI),can be used for data assimilation in heterogenous ***,the new Sentinel 2 Multispectral instrument and Landsat 8 Operational Land Imager sensor data are available at such high temporal and spatial resolutions that can be used to detect the patches of the main vegetation components(grass and trees)of heterogenous ecosystems,and capture their *** demonstrate the possibility to merge grass and tree NDVI observations and models,to optimally provide robust predictions of grass and tree leaf area *** proposed assimilation approach assimilates NDVI data through the Ensemble Kalman filter(EnKF)and dynamically calibrates a key vegetation dynamic model parameter,the maintenance respiration coeffcient(ma).In the presence of large bias of the grass and tree ma base values,only the use of the proposed assimilation approach removes the large bias in the biomass balance,dynamically calibrating maintenance respiration coefficients,and corrects the *** performance of a land surface-vegetation model was improved by assimilating observations of *** effective impact of the proposed assimilation approach on the evapotranspiration and CO_(2) uptake predictions in the heterogenous ecosystem is also demonstrated.

关键词： Data assimilation leaf area index heterogenous ecosystem vegetation dynamic model Landsat 8 Sentinel 2

Perturbed initial orbit determination

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Astrodynamics 2024年第3期8卷 401-416页

作者： Alberto Fossà Matteo Losacco roberto Armellin Institut Supérieur de l’Aéronautique et de l’Espace Toulouse31400France Te PūnahaĀtea-Space Institute The University of AucklandAuckland1010New Zealand

An algorithm for robust initial orbit determination (IOD) under perturbed orbital dynamics is presented. By leveraging map inversion techniques defined in the algebra of Taylor polynomials, this tool returns a highly accurate solution to the IOD problem and estimates a range centered on the aforementioned solution in which the true orbit should lie. To meet the specified accuracy requirements, automatic domain splitting is used to wrap the IOD routines and ensure that the local truncation error, introduced by a polynomial representation of the state estimate, remains below a predefined threshold. The algorithm is presented for three types of ground-based sensors, namely range radars, Doppler-only radars, and optical telescopes, by considering their different constraints in terms of available measurements and sensor noise. Finally, the improvement in performance with respect to a Keplerian-based IOD solution is demonstrated using large-scale numerical simulations over a subset of tracked objects in low Earth orbit.

关键词： initial orbit determination(IOD) range radar Doppler radar optical telescope differential algebra(DA)

Taste sensitivity and divergence in host plant acceptance between adult females and larvae of Papilio hospiton

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Insect Science 2018年第5期25卷 809-822页

作者： Giorgia Sollai Maurizio Biolchini roberto Crnjar Department of Biomedical Sciences Section of Physiology University of Cagliari 09042 Monserrato (CA) Italy

On the island of Sardinia the lepidopteran Papilio hospiton uses Ferula com- munis as exclusive host plant. However, on the small island of Tavolara, adult females lay eggs on Seseli tortuosum, a plant confined to the island. When raised in captivity on Seseli only few larvae grew beyond the first-second instar. Host specificity of lepidopterans is determined by female oviposition preferences, but also by larval food acceptance, and adult and larval taste sensitivity may be related to host selection in both cases. Aim of this work was：（i） to study the taste sensitivity of larvae and ovipositing females to saps of Ferula and Seseli; （ii） to cross-compare the spike activity of gustatory receptor neurons （GRNs） to both taste stimuli; （iii） to evaluate the discriminating capability between the two saps and determine which neural code/s is/are used. The results show that：（i） the spike responses of the tarsal GRNs of adult females to both plant saps are not different and therefore they cannot discriminate the two plants; （ii） larval L-lat GRN shows a higher activity in response to Seseli than Ferula, while the opposite occurs for the phagostimulant neurons, and larvae may discriminate between the two saps by means of multiple neural codes; （iii） the number of eggs laid on the two plants is the same, but the larval growth performance is better on Ferula than Seseli. Taste sensitivity differences may explain the absence of a positive relationship between oviposition preferences by adult females and plant acceptance and growth performance by larvae.

关键词： chemoreception feeding acceptance host-plant discrimination neural cod-ing oviposition preference Papilionidae

Three Dimensional Coupling between Elastic and Thermal Fields in the Static Analysis of Multilayered Composite Shells

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2551-2594页

作者： Salvatore Brischetto roberto Torre Domenico Cesare Department of Mechanical and Aerospace Engineering.Politecnico di Torino Torino10129Italy

This new work aims to develop a full coupled thermomechanical method including both the temperature profile and displacements as primary unknowns of the *** generic full coupled 3D exact shell model permits the thermal stress investigation of laminated isotropic,composite and sandwich *** and spherical panels,cylinders and plates are analyzed in orthogonal mixed curved reference *** 3D equilibrium relations and the 3D Fourier heat conduction equation for spherical shells are coupled and they trivially can be simplified in those for plates and cylindrical *** exponential matrix methodology is used to find the solutions of a full coupled model based on coupled differential relations with respect to the thickness *** analytical solution is based on theories of simply supported edges and harmonic relations for displacement components and *** sovra-temperature magnitudes are directly applied at the outer faces through static state *** a consequence,the sovra-temperature description is assumed to be an unknown variable of themodel and it is calculated in the sameway as the three *** final systemis based on a set of coupled homogeneous differential relations of second order in the thickness *** system is reduced in a first order differential relation system by redoubling the number of ***,the exponential matrix methodology is applied to calculate the *** temperature field effects are evaluated in the static investigation of shells and plates in terms of displacement and stress *** an appropriate preliminary validation,new benchmarks are discussed for several thickness ratios,geometrical data,lamination sequences,materials and sovra-temperature values imposed at the outer *** make evident the accordance between the uncoupled thermo-mechanical model and this new full coupled thermo-mechanical model without the need to se

关键词： Three-dimensional exact thermo-elastic shellmodel full coupled thermoelasticity three-dimensional fourier heat conduction relation plate and shell geometries laminated and sandwich configurations

Mapping and ultrastructure of antennal chemosensilla of the wheat bug Eurygaster maura

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Insect Science 2009年第2期16卷 193-203页

作者： roberto Romani Marco Valerio Rossi Stacconi Dipartimento di Scienze Agrarie e Ambientali Facolt& di Agraria Universit& degli Studi di Perugia Perugia Italy

Antennae of the wheat stink bug Eurygaster maura L. （Hemiptera： Scutelleridae） were investigated to elucidate structure and distribution of antennal chemosensilla in females. Five type of sensilla were identified and characterized using a scanning electron microscope （SEM） and a transmission electron microscope （TEM）. Type 1 sensilla are mechanical and contact chemoreceptors with a single apical pore. Types 2 and 3 sensilla are multiporous chemoreceptors both with typical features of olfactory sensilla. Type 4 are multiporous peg-like sensilla, short and with a grooved surface. Type 5 are sensilla coeloconica with a smooth and aporous peg completely inserted in a sub-cuticular chamber. All types are distributed on the two flagellar segments, but we considered only the apical flagellomere in which the largest number of sensilla are located. The most abundant sensilla are type 3, while the less numerous are type 5. All types, except type 2, decreased in number from the tip to the base of the segment. The lower density of sensilla was recorded on the dorsal-internal part of the apical antennomere, while the higher density was recorded on the opposite side （external-ventral）.

关键词： functional anatomy gustatory sensilla Hemiptera olfactory sensilla thermo-hygro receptors

Oxidative desulfurization of diesel fuel oil using supported Fenton catalysts and assisted with ultrasonic energy

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Petroleum Science 2019年第5期16卷 1176-1184页

作者： roberto Flores Arturo Rodas Raquel Gasperin Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de MorelosAv.Universidad No.1001Col.Chamilpa62209 CuernavacaMorelosMexico Gerencia de Materiales y Procesos Químicos Instituto Nacional de Electricidad y Energías LimpiasCalle Reforma 113Col.Palmira62490 CuernavacaMorelosMexico

An ultrasound-assisted heterogeneous catalytic oxidation process was applied to eliminate sulfur from commercial diesel fuel *** studied variables were catalyst concentration,type of catalyst(homogeneous or heterogeneous),oxidizing agent concentration,and the application of ultrasound *** catalysts were prepared by impregnation of coal fly ash with an iron(Ⅱ)sulfate aqueous solution using ultrasound *** drying,the catalyst was calcined at 500℃for 4 *** oxidizing agent was hydrogen *** energy was applied with a frequency of 47 kHz and an intensity of 147 *** was employed for extracting the oxidized compounds from the hydrocarbon *** fly ash and ethanol were used with the purpose of applying low-cost raw materials in chemical *** was found that under the studied conditions,increasing oxidizing agent concentration and the application of ultrasound energy can enhance the sulfur removal from commercial diesel fuel *** concentration did not play a significant role in the *** results were obtained using homogeneous or heterogeneous catalyst,which is important since the heterogeneous catalyst could be recovered,reactivated,and used in many cycles.

关键词： Oxidative desulfurization Diesel Ultrasound energy Supported catalyst Low-cost raw materials

Multiple mating by both sexes in an invasive insect species,Aethina tumida(Coleoptera:Nitidulidae)

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Insect Science 2023年第2期30卷 517-529页

作者： Anna Papach Alexis Beaurepaire orlando Yanez Meret Huwiler Geoffrey R.Williams Peter Neumann Institute of Bee Health Vetsuisse FacultyUniversity of BernBernSwitzerland Agroscope Swiss Bee Research CentreBernSwitzerland Department of Entomology&Plant Pathology Auburn UniversityAuburnAlabamaUSA

Multiple mating by both sexes is common among sexually reproducing *** hive beetles(SHB),Aethina tumida,are parasites of bee nests endemic to sub-Saharan Africa and have become a widespread invasive *** the considerable economic damages they can cause,their basic biology remains poorly *** we show that male and female small hive beetles can mate multiple times,suggesting that costs for mating are low in this *** an invasive *** population in the United States,a combination of laboratory experiments for males and paternity analysis with eight polymorphic DNA microsatellite markers for field-caught females were used to estimate the number of mating by both *** data show that females and males can mate multiple times—females mated with up to eight males,whereas males mated with at least seven *** results also showed that *** displayed a skewed paternity,although this was not consistent among the tested ***,first or last male advantage seem to be unlikely in *** observations that individuals of both sexes of *** can mate multiple times opens new research avenues for examining drivers of multiple mating and determining the role it may play in promoting biological invasions.

关键词： evolution of sex invasive species multiple partners polygynandry reproductive biology

Hyperglycemia in acute ischemic stroke: physiopathological and therapeutic complexity

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Neural Regeneration Research 2022年第2期17卷 292-299页

作者： Federica Ferrari Antonio Moretti roberto Federico Villa Department of Biology and Biotechnology Laboratory of Pharmacology and Molecular Medicine of Central Nervous SystemUniversity of PaviaVia FerrataPaviaItaly

Diabetes mellitus and associated chronic hyperglycemia enhance the risk of acute ischemic stroke and lead to worsened clinical outcome and increased mortality. However, post-stroke hyperglycemia is also present in a number of non-diabetic patients after acute ischemic stroke, presumably as a stress response. The aim of this review is to summarize the main effects of hyperglycemia when associated to ischemic injury in acute stroke patients, highlighting the clinical and neurological outcomes in these conditions and after the administration of the currently approved pharmacological treatment, i.e. insulin. The disappointing results of the clinical trials on insulin(including the hypoglycemic events) demand a change of strategy based on more focused therapies. Starting from the comprehensive evaluation of the physiopathological alterations occurring in the ischemic brain during hyperglycemic conditions, the effects of various classes of glucose-lowering drugs are reviewed, such as glucose-like peptide-1 receptor agonists, DPP-4 inhibitors and sodium glucose cotransporter 2 inhibitors, in the perspective of overcoming the up-to-date limitations and of evaluating the effectiveness of new potential therapeutic strategies.

关键词： acute ischemic stroke diabetes mellitus DPP-4 inhibitor glucose-like peptide-1 receptor agonist hyperglycemia hypoglycemia insulin physiopathology sodium glucose cotransporter 2 inhibitor

Influence of Surface Finishing on High-Temperature Oxidation of AISI Type 444 Ferritic Stainless Steel Used in SOFC Stacks

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 697-711页

作者： Valeria Bongiorno Paolo Piccardo Simone Anelli roberto Spotorno Laboratorio di Metallurgia e Materiali - Dipartimento di Chimica e Chimica Industriale (LMM-DCCI) Universita degli Studi di Genova Via Dodecaneso 31 16146 GenoaItaly

This research is focused on the study of the samples, approximatively 15 × 30 mm^2 sized, that were mechanically cut from two sheets （0.4 and 0.2 mm thick, respectively） of AIS1444 Type ferritic stainless steel （FSS）（DIN 1.4521, Eu designation X2CrMoTil8-2）; this material was in the ＇as-rolled＇ state. Part of these specimens were treated superficially on one side using abrasive SiC papers with different average grit sizes （i.e., 46.2, 30.2, 18.3 gm） and diamond suspension （up to 1 tim） in order to obtain various surface roughness. Both the ＇as-rolled＇ and superficially treated samples were then aged in a muffle fumace in static air according to a thermal cycle corresponding to the curing phase of an experimental glass used as sealing in the solid oxide fuel cell stacks. After aging, the chemical compositions and mor- phological peculiarities of the scale formed depending on the thickness of the samples and their surface state were studied by scanning electron microscopy, energy-dispersive spectroscopy, micro-Raman spectroscopy, bright field light optical microscopy. The obtained results show that all scales formed consist of an inner Cr2O3 subscale and an outer （Mn,Cr）3O4 spinel layer; the relationship between FSS grain size and scale microstructural features is consistent on the samples with mirror-like surface only; the scale thicknesses on SiC grinded samples are comparable; the scales covering the ＇as-rolled＇ surfaces are morphologically similar to those grown on the surfaces finished with the 30.2 and 18.3 μm SiC papers, and their thicknesses show an intermediate situation between the abraded and the mirror-like specimens. The last described characteristics depend mainly on the surface and microstructural peculiarities resulting from the rolling process.

关键词： AISI Type 444 SOFC stacks Surface roughness Microstructure Surface finishing High-temperature oxidation

Dynamical Criticality:Overview and Open Questions

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Journal of Systems Science & Complexity 2018年第3期31卷 647-663页

作者： ROLI Andrea VILLANI Marco FILISETTI Alessandro SERRA roberto Department of Computer Science and Engineering (DISI) Campus of Cesena University of Bologna Italy Department of Physics Informatics and Mathematics University of Modena and Reggio Emilia Italy European Centre for Living Technology Venezia Italy Explora s.r.l. Roma Italy & European Centre for Living Technology Venezia Italy

Systems that exhibit complex behaviours are often found in a particular dynamical con- dition, poised between order and disorder. This observation is at the core of the so-called criticality hypothesis, which states that systems in a dynamical regime between order and disorder attain the highest level of computational capabilities and achieve an optimal trade-off between robustness and flexibility. Recent results in cellular and evolutionary biology, ueuroscience and computer science have revitalised the interest in the criticality hypothesis, emphasising its role as a viable candidate general law in adaptive complex systems. This paper provides an overview of the works on dynamical criticality that are -- To the best of our knowledge -- Particularly relevant for the criticality hypothesis. The authors review the main contributions concerning dynamics and information processing at the edge of chaos, and illustrate the main achievements in the study of critical dynamics in biological systems. Finally, the authors discuss open questions and propose an agenda for future work.

关键词： Attractors criticality dynamical regimes edge of chaos phase transitions.