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Solvability of the Dirichlet Problem in W^(2,p )for a Class of Elliptic Equations with Singular Data

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Acta Mathematica Sinica,English Series 2014年第5期30卷 737-746页

作者： Loredana CASO roberta D'AMBROSIO Maria TRANSIRICO Dipartimento di Matematica Universit`a di SalernoVia Giovanni Paolo II 132I - 84084 Fisciano (SA) Italy

We prove an existence and uniqueness result for the Dirichlet problem for a class of elliptic equations with singular data in weighted Sobolev spaces.

关键词： Elliptic equations a priori estimates uniqueness and existence results weighted spaces

On the criteria to create a susceptibility map to debris flow at a regional scale using Flow-R

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Journal of Mountain Science 2017年第4期14卷 621-635页

作者： PASTORELLO roberta MICHELINI Tamara D'AGOSTINO Vincenzo Department of Land EnvironmentAgriculture and Forestry(TeSAF)University of Padova35020 LegnaroItaly

Studies on susceptibility to debris flows at regional scale （ioo-looo km2） are important for the protection and management of mountain areas. To reach this objective, routing models, mainly based on land topography, can be used to predict susceptible areas rapidly while necessitating few input data. In this research, Flow-R model is implemented to create the susceptibility map for the debris flow of the Vizze Valley （BZ, North-Eastern Italy; 134 km^2）. The analysis considers the model application at local scale for three sub-catchments and then it explores the model upsealing at the regional scale by verifying two methods to generate the source areas of debris-flow initiation. Using data of an extreme event occurred in the Vizze Valley （4 August 2012） and historical information, the modeling verification highlights that the propagation parameters are relatively simple to set in order to obtain correct runout distances. A double DTM filtering - using a threshold for the upslope contributing area （0.1 km^2） and a threshold for the terrain-slope angle （15°） provides a satisfactory prediction of source areas and susceptibility map within the geological conditions of the Vizze Valley.

关键词： Debris flow Susceptibility map Flow-R Triggering areas Regional scale Alpine valley

Bedrock geology interacts with altitude in affecting leaf growth and foliar nutrient status of mountain vascular plants

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Journal of Plant Ecology 2017年第5期10卷 839-850页

作者： Renato Gerdol roberta Marchesini Paola Iacumin Department of Life Sciences and Biotechnology University of FerraraCorso Ercole I d’Este 32I-44121 FerraraItaly Department of Physics and Earth Sciences University of ParmaViale delle Scienze 158/AI-43124 ParmaItaly

Aims Altitude is often used as a proxy for ascertaining how warming affects plant growth and leaf level ***,we have a poor understanding of how the effects of altitude-related warming varies across ***,this study examined the independ-ent and interactive effects of altitude and geology and species on plant growth and foliar nutrient *** We determined leaf growth rates and concentrations of major nutrients(nitrogen,N and phosphorus,P)in leaves of five spe-cies across two altitudinal gradients(1200-2200 m)in the Dolomites(south-eastern Alps,Italy).the two transects were located on carbonate bedrock and silicate bedrock,*** also determined concentrations of inorganic and organic N and P forms in soils,andδ15N signature in leaves and *** Findings Foliar N concentrations were unrelated to bedrock *** negative foliarδ^(15)N signature suggested that organic N was the primary source of N supply across the *** P concentrations were strongly affected by bedrock geology and their altitudinal patterns depended on the concentrations of organic and inorganic P forms in the *** and organic P appeared to be the main sources of P *** growth rates increased with higher altitude on silicate bedrock and decreased with higher altitude on carbonate bedrock and presented a significant positive correlation with foliar N:*** conclusion,bedrock geology inter-acted with altitude in controlling the foliar nutrient status mainly owing to availability of soil P and its effect on foliar nutrient stoichiometry.

关键词： altitude mycorrhiza plant functional type soil chemistry ^(15)N

Oil-in-water nanoemulsions loaded with lycopene extracts encapsulated by spray drying:Formulation,characterization and optimization

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Chinese Journal of Chemical Engineering 2024年第6期70卷 73-81页

作者： Junyang Li roberta Campardelli Giuseppe Firpo Jingtao Zhang Patrizia Perego Department of Civil Chemical and Environmental Engineering(DICCA)University of GenoaVia Opera Pia 15Genova 16145Italy Department of Physics University of GenoaVia Dodecaneso 32Genova 16146Italy School of Food and Bioengineering Zhengzhou University of Light IndustryZhengzhou 450002China

Lycopene is very susceptible to degradation once released from the protective chromoplast *** this study,oil-in-water(O/W)nanoemulsions coupled with spray drying technology were applied for the encapsulation and stabilization of lycopene extracted from tomato *** extract was obtained by ultrasound-assisted *** were prepared by a high-speed rotor stator using isopropyl myristate as the oil phase and Pluronic F-127 as the emulsifier for the aqueous external *** effect of emulsification process parameters was *** drying of the produced emulsions was attempted to obtain a stabilized dry powder after the addition of a coating *** effect of different coating agents(maltodextrin,inulin,gum arabic,pectin,whey and polyvinylpyrrolidone),drying temperature(120-170℃),and feed flow rate(3-9 ml·min^(-1))on the obtained particles was *** revealed that the emulsion formulation of 20/80(O/W)with 1.5%(mass fraction)of Pluronic F-127 as stabilizer in the aqueous phase resulted in a stable nanoemulsion with droplet sizes in the range of 259-276 nm with a unimodal and sharp size *** extract in the nanoemulsion was well protected at room temperature with a degradation rate of lycopene of about 50%during a month of storage *** most stable emulsions were then processed by spray drying to obtain a dry *** drying was particularly successful when using maltodextrin as a coating agent,obtaining dried spherical particles with mean diameters of(4.87±0.17)μm with a smooth *** possibility of dissolving the spray dried powder in order to *** original emulsion was also successfully verified.

关键词： Emulsions Powders Stability Isopropyl myristate Lycopene Spray-drying

Paediatric retinal detachment:a review

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International Journal of Ophthalmology(English edition) 2017年第10期10卷 1592-1603页

作者： Raffaele Nuzzi Carlo Lavia roberta Spinetta Eye Clinic Department of Surgical SciencesUniversity of Turin

Paediatric retinal detachment（PRD）is an uncommon and challenging disease;it differs from adult detachments in etiology,anatomical characteristics,management and *** can be particularly challenging,even for the most expert paediatric surgeons due to the higher prevalence of total retinal detachments,late diagnosis and bilateral involvement with respect to those which occur in ***,the anatomical success,when achieved,is frequently not related to a functional *** adverse events,refractive errors and amblyopia may additionally undermine the final *** to date there are few reviews regarding the approach of retinal detachment in children,mainly dealing with rhegmatogenous retinal *** this review,rhegmatogenous,retinopathy of prematurityrelated and Coats’-related PRDs were *** available literature from the last decades were reviewed and ***,etiology and clinical presentation,together with therapeutic approaches and outcomes have been reviewed and discussed.

关键词： paediatric retinal detachment paediatric rhegmatogenous retinal detachment retinopathy of prematurity Coats' disease

Treatment, residual chlorine and season as factors affecting variability of trihalomethanes in small drinking water systems

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Frontiers of Environmental Science & Engineering 2015年第1期9卷 171-179页

作者： roberta DYCK Genevieve COOL Manuel RODRIGUEZ Rehan SADIQ School of Engineering University of British Columbia Okanagan Kelowna V1V 1V7 Canada Ecole superieure d'amenagement du territoire Universite Laval Quebec G1V 0A6 Canada

Seasonal variability in source water can lead to challenges for drinking water providers related to operational optimization and process control in treatment facilities. The objective of this study is to investigate seasonal variability of water quality in municipal small water systems （〈 3000 residents） supplied by surface waters. Residual chlorine and trihalomethanes （THM） were measured over seven years （2003-2009）. Comparisons are made within each system over time, as well as between systems according to the type of their treatment technologies. THM concentrations are generally higher in the summer and autumn. The seasonal variability was generally more pronounced in systems using chlorination plus additional treatment. Chloroform, total THM （TTHM） and residual chlorine concentrations were generally lower in systems using chlorination plus additional treatment. Conversely, brominated THM concentrations were higher in systems using additional treatment. Residual chlorine was highest in the winter and lowest in the spring and summer. Seasonal variations were most pronounced for residual chlorine in systems with additional treatment. There was generally poor correlation between THM concentrations and concentrations of residual chlorine. Further study with these data will be beneficial in finding determinants and indicators for both quantity and variability of disinfection byproducts and other water quality parameters.

关键词： drinking water residual chlorine seasonal variability small municipal systems treatment technologies trihalomethanes

Multiple aspects of the maternal reproductive investmentin a polytocous species:What do mothers really control?

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Current Zoology 2023年第2期69卷 136-142页

作者： Rudy Brogi roberta Chirichella Enrico Merli Marco Apollonio Department of Veterinary Medicine University of Sassarivia Vienna 2I-07100 SassariItaly Department of Humanities and Social Sciences University of Sassarivia Roma 151I-07100 SassariItaly

One of the factors facilitating the expansion and proliferation of wild boar Sus scrofa is the plasticity of its reproductive ***,the real influence of maternal and environmental factors on number and sex of the offspring is stll *** the litter size was shown to be related with the maternal condition,the strength of this relation remains to be understood,together with the possible role played by environmental ***,it is unclear whether wild boar females can adjust their offspring *** investigated multiple aspects of wild boar maternal investment by means of a 10-year dataset of female reproductive traits and a set of biologically meaningful environmental *** maternal condition slightly affected the litter size but not the offspring sex,and environment did not affect the litter size or the offspring ***,mothers did not cope with the higher costs entailed by producing sons by placing them in the most advantageous intrauterine position,nor by allocating less resources on *** set of results showed that the female reproductive investment is quite rigid in comparison with other aspects of wild boar reproductive *** boar females seem to adopt a typical rstrategy,producing constantly large litters and allocating resources on both sexes regardless of internal and external *** strategy may be adaptive to cope with environmental unpredictability and an intense human harvest,contributing to explain the extreme success of wild boar within human-dominated landscapes.

关键词： investment life history litter size reproduction sex allocation wild boar

Flare evolution and polarization changes in fine structures of solar radio emission in the 2013 April 11 event

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Research in Astronomy and Astrophysics 2016年第2期16卷 69-80页

作者： Gennady Chernov Robert sych Bao-Lin Tan Yi-Hua Yan Cheng-Ming Tan Qi-Jun Fu Marian Karlicky Valery Fomichev Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences(IZMIRAN)TroitskMoscow region142190Russia Yunnan Observatories Chinese Academy of SciencesKunming 650011China Institute of Solar-Terrestrial Physics Russian Academy of SciencesSiberian BranchIrkutsk 664033Russia Astronomical Institute of the Academy of Sciences of the Czech Republic Ondrejov 15165Czech Republic

The measurement of positions and sizes of radio sources in observations is important for un- derstanding of the flare evolution. For the first time, solar radio spectral fine structures in an M6.5 flare that occurred on 2013 April 11 were observed simultaneously by several radio instruments at four different observatories： Chinese Solar Broadband Radio Spectrometer at Huairou （SBRS/Huairou）, Ondrejov Radio Spectrograph in the Czech Republic （ORSC/Ondrejov）, Badary Broadband Microwave Spectropolarimeter （BMS/Irkutsk）, and spectrograph/IZMIRAN （Moscow, Troitsk）. The fine structures included microwave zebra patterns （ZPs）, fast pulsations and fiber bursts. They were observed during the flare brightening lo- cated at the tops of a loop arcade as shown in images taken by the extreme ultraviolet （EUV） telescope onboard NASA＇s satellite Solar Dynamics Observatory （SDO）. The flare occurred at 06：58-07：26 UT in solar active region NOAA 11719 located close to the solar disk center. ZPs appeared near high frequency boundaries of the pulsations, and their spectra observed in Huairou and Ondrejov agreed with each other in terms of details. At the beginning of the flare＇s impulsive phase, a strong narrowband ZP burst occurred with a moderate left-handed circular polarization. Then a series of pulsations and ZPs were observed in almost unpolarized emission. After 07：00 UT a ZP appeared with a moderate right-handed polarization. In the flare decay phase （at about 07：25 UT）, ZPs and fiber bursts become strongly right-hand polarized. BMS/Irkutsk spectral observations indicated that the background emission showed a left-handed circular polarization （similar to SBRS/Huairou spectra around 3 GHz）. However, the fine structure appeared in the right-handed polarization. The dynamics of the polarization was associated with the motion of the flare ex- citer, which was observed in EUV images at 171 A and 131 A by the SDO Atmospheric Imaging Assembly （AIA）. Combining magnetograms observed by t

关键词： Sun activity -- Sun flares -- Sun particle emission -- Sun radio radiation -- zebra-pattern

Gut-brain axis:does intestinal inflammation affect hippocampal neurogenesis and medulloblastoma development?

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Neural Regeneration Research 2023年第11期18卷 2381-2382页

作者： Arianna Casciati Mariateresa Mancuso roberta Vitali Simonetta Pazzaglia Biomedical Technologies Laboratory Agenzia Nazionale per le Nuove Tecnologiel’Energia e lo Sviluppo Economico Sostenibile(ENEA)RomeItaly

Gut-brain axis:does intestinal inflammation affect hippocampal neurogenesis and medulloblastoma development?Inflammatory bowel diseases (IBD) are a group of disorders that cause chronic inflammation in the intestines,associated with altered intestinal permeability,which in turn causes an immune response to enteric antigens in a gen etically susceptible *** incidence is high in industrialized countries and continuously rises in emerging economies.

关键词： inflammation diseases continuously