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Transcriptome‑wide mapping of milk somatic cells upon subclinical mastitis infection in dairy cattle
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作者 Vittoria Bisutti Nuria Mach +7 位作者 Diana Giannuzzi Alice Vanzin Emanuele Capra Riccardo Negrini Maria Elena Gelain Alessio Cecchinato Paolo Ajmone‑Marsan Sara Pegolo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2630-2648,共19页
Background Subclinical intramammary infection(IMI)represents a significant problem in maintaining dairy cows’health.Disease severity and extent depend on the interaction between the causative agent,environment,and ho... Background Subclinical intramammary infection(IMI)represents a significant problem in maintaining dairy cows’health.Disease severity and extent depend on the interaction between the causative agent,environment,and host.To investigate the molecular mechanisms behind the host immune response,we used RNA-Seq for the milk somatic cells(SC)transcriptome profiling in healthy cows(n=9),and cows naturally affected by subclinical IMI from Proto-theca spp.(n=11)and Streptococcus agalactiae(S.agalactiae;n=11).Data Integration Analysis for Biomarker discov-ery using Latent Components(DIABLO)was used to integrate transcriptomic data and host phenotypic traits related to milk composition,SC composition,and udder health to identify hub variables for subclinical IMI detection.Results A total of 1,682 and 2,427 differentially expressed genes(DEGs)were identified when comparing Prototheca spp.and S.agalactiae to healthy animals,respectively.Pathogen-specific pathway analyses evidenced that Proto-theca’s infection upregulated antigen processing and lymphocyte proliferation pathways while S.agalactiae induced a reduction of energy-related pathways like the tricarboxylic acid cycle,and carbohydrate and lipid metabolism.The integrative analysis of commonly shared DEGs between the two pathogens(n=681)referred to the core-mastitis response genes,and phenotypic data evidenced a strong covariation between those genes and the flow cytometry immune cells(r2=0.72),followed by the udder health(r2=0.64)and milk quality parameters(r2=0.64).Variables with r≥0.90 were used to build a network in which the top 20 hub variables were identified with the Cytoscape cyto-hubba plug-in.The genes in common between DIABLO and cytohubba(n=10)were submitted to a ROC analysis which showed they had excellent predictive performances in terms of discriminating healthy and mastitis-affected animals(sensitivity>0.89,specificity>0.81,accuracy>0.87,and precision>0.69).Among these genes,CIITA could play a key role in regulating the animals’response to subclinical IMI.Conclusions Despite some differences in the enriched pathways,the two mastitis-causing pathogens seemed to induce a shared host immune-transcriptomic response.The hub variables identified with the integrative approach might be included in screening and diagnostic tools for subclinical IMI detection. 展开更多
关键词 Data integration Immune response Milk somatic cells RNA-sequencing Subclinical mastitis
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Ontological Model for Cohesive Smart Health Services Management
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作者 Muhammad Raza Naqvi Muhammad Waseem Iqbal +3 位作者 Syed Khuram Shahzad M.Usman Ashraf Khalid Alsubhi Hani Moaiteq Aljahdali 《Computers, Materials & Continua》 SCIE EI 2023年第2期3679-3695,共17页
Health care has become an essential social-economic concern for all stakeholders(e.g.,patients,doctors,hospitals etc.),health needs,private care and the elderly class of society.The massive increase in the usage of he... Health care has become an essential social-economic concern for all stakeholders(e.g.,patients,doctors,hospitals etc.),health needs,private care and the elderly class of society.The massive increase in the usage of health care Internet of things(IoT)applications has great technological evolvement in human life.There are various smart health care services like remote patient monitoring,diagnostic,disease-specific remote treatments and telemedicine.These applications are available in a split fashion and provide solutions for variant diseases,medical resources and remote service management.The main objective of this research is to provide a management platform where all these services work as a single unit to facilitate the users.The ontological model of integrated healthcare services is proposed by getting requirements from various existing healthcare services.There were 26 smart health care services and 26 smart health care services to classify the knowledge-based ontological model.The proposed ontological model is derived from different classes,relationships,and constraints to integrate health care services.This model is developed using Protégébased on each interrelated/correlated health care service having different values.Semantic querying SPARQL protocol and RDF query language(SPARQL)were used for knowledge acquisition.The Pellet Reasoner is used to check the validity and relations coherency of the proposed ontology model.Comparative to other smart health care services integration systems,the proposed ontological model provides more cohesiveness. 展开更多
关键词 ONTOLOGY internet of things smart health services integration
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Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au^(+) ions and a capping agent
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作者 Tatiana HABIB José Mauricio A.CAIUT Bruno CAILLIER 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期108-115,共8页
Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse... Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive species.These species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid solution.In this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit agglomerations.The formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink color.This was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(SPR)band.An investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold nanoparticles.Dynamic light scattering(DLS)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XRD)was also employed to determine their crystallographic structure.The results confirm that homogeneous spherical gold nanoparticles with an average diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma. 展开更多
关键词 gold nanoparticles NON-THERMAL plasma jet HELIUM DBD
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Electrochemical Analysis of Zirconiumin Aqueous and Organic Media
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作者 Paul Mendy Démo Koita +2 位作者 Theodore Tzedakis Cheikhou Kane Codou Guèye Mar-Diop 《American Journal of Analytical Chemistry》 CAS 2024年第2期99-118,共20页
For the challenging nature of the zirconium environment analysis, this study consists to analyze the electrochemical behavior of Zirconium in both aqueous and organic media. To that end first the electrolytic media wa... For the challenging nature of the zirconium environment analysis, this study consists to analyze the electrochemical behavior of Zirconium in both aqueous and organic media. To that end first the electrolytic media was selected on the basis of the Pourbaix potential-pH diagram, which provides informations on the predominance of Zr<sup>(IV) </sup> ion and Zr in aqueous media. In aqueous media, analyzes were first carried out in acidic media then in basic media. Studies have thus revealed that the acidic environment is not favourable for the electrochemical analysis of zirconium. Voltammograms obtained in an acidic environment show no zirconium detection signal;this is due to the strong presence of H<sup>+</sup> ions in the solution. We have also observed in acidic media the phenomenon of passivation of the electrode surface. In aqueous alkaline media (pH = 13), we have drawn in reduction several Intensity-Potential curves by fixingsome technical parameterslike scanning speed, rotation speed of the electrode. The obtained voltammograms show cathodic waves, starting from -1.5 V/DHW and attributed to the reduction of Zr<sup> (IV) </sup> to Zr (0). The last phase of this study focused on the electrochemical analysis of zirconium in an organic media. In this media, several intensity-potential curves were plotted in reduction and in cyclic voltammetry with various parameters. Through several reduction analysis, the Zr<sup> (IV) </sup> was reduced to Zr (0) to the potential of -1.5 V/DHW. The electrochemical analysis of zirconium in organic media seems globally easier to achieve thanks to its large solvent window (i.e. dimethylformamide (DMF) solvent window > 6 V). 展开更多
关键词 ZIRCONIUM ELECTROCHEMICAL REDUCTION Cyclic Voltammetry VOLTAMMOGRAM Dymethylformamide
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The Drought of Amazonia in 2023-2024
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作者 Jose A. Marengo Ana P. Cunha +7 位作者 Jhan-Carlo Espinoza Rong Fu Jochen Schöngart Juan C. Jimenez Mabel C. Costa Joao M. Ribeiro Sly Wongchuig Siyu Zhao 《American Journal of Climate Change》 2024年第3期567-597,共31页
The Amazon basin has experienced an extreme drought that started in the austral summer of 2022-23 and extends into 2024. This drought started earlier than other previous droughts. Although some rain fell during the au... The Amazon basin has experienced an extreme drought that started in the austral summer of 2022-23 and extends into 2024. This drought started earlier than other previous droughts. Although some rain fell during the austral summer, totals remained below average. Higher temperatures during austral winter and spring 2023, which affected most of Central South America, then aggravated drought conditions. This coincided with an intense El Niño and abnormally warm tropical North Atlantic Ocean temperatures since mid-2023. Decreased rainfall across the Amazon basin, negative anomalies in evapotranspiration (derived from latent heat) and soil moisture indicators, as well as increased temperatures during the dry-to-wet transition season, September-October-November (SON) 2023, combined to delay the onset of the wet season in the hydrological year 2023-24 by nearly two months and caused it to be uncharacteristically weak. SON 2023 registered a precipitation deficit of the order of 50 to 100 mm/month, and temperatures +3˚C higher than usual in Amazonia, leading to reduced evapotranspiration and soil moisture indicators. These processes, in turn, determined an exceptionally late onset and a lengthening of the dry season, affecting the 2023-2024 hydrological year. These changes were aggravated by a heat wave from June to December 2023. Drought-heat compound events and their consequences are the most critical natural threats to society. River levels reached record lows, or dried up completely, affecting Amazonian ecosystems. Increased risk of wildfires is another concern exacerbated by these conditions. 展开更多
关键词 El Niño SST in the Tropical Atlantic AMAZON DROUGHT River Levels HEATWAVE Dry Season Length
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The Impact of the Inclusion of MgO Nano-Fillers in a Polyethylene Matrix on Dielectric Strength and Resistance to Partial Discharges
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作者 Virginie Griseri Dominique Mary +1 位作者 David Malec Eric David 《Open Journal of Applied Sciences》 2024年第3期626-634,共9页
One commonly used strategy to enhance polymers specific properties such as the resistance to partial discharges erosion is the incorporation into the polymeric matrix of inorganic micro or nanoparticles. This study fo... One commonly used strategy to enhance polymers specific properties such as the resistance to partial discharges erosion is the incorporation into the polymeric matrix of inorganic micro or nanoparticles. This study focused on the dielectric properties of Low-Density Polyethylene (LDPE) filled with nano-sized Magnesium Oxide (MgO) particles compounded by thermo-mechanical process and one of the purposes was to establish appropriate processing parameters in order to reach the desired dielectric properties. LDPE was used as a matrix and was reinforced by MgO particles having a nominal average size of 30 nm. The MgO nanoparticles were treated with a silane coupling agent (3-Glycidyloxypropyl Trimethoxysilane). The samples were initially prepared in a melt-mixing chamber with a MgO content of 1% wt. These pre-mixed samples were further treated by the means of thermo-mechanical mixing in a conical co-rotating twin-screw extruder in order to improve the dispersion and distribution of the MgO particles. In this report, both lifetime under a PD activity and AC dielectric strength of pure and nano-filled LDPE samples have been measured and compared. Nano-filled LDPE samples were found to exhibit an improve lifetime, without any detrimental impact on their short-term dielectric strength. This suggests that nano-filled LDPE may be for electric applications for which the dielectric materials may be exposed to partial discharge activities. This is significant result for the use of MgO-reinforced PE as an insulating material for HV cables since the resistance to PD is closely related to treeing resistance which is the main electrical degradation mechanism that leads to failure for shielded extruded power cables. 展开更多
关键词 Low Density Polyethylene MgO Nanofillers Dielectric Strength Partial Discharges Resistance
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Adipose-derived stromal cells: Their identity and uses in clinical trials, an update 被引量:33
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作者 Louis Casteilla Valérie Planat-Benard +1 位作者 Patrick Laharrague Béatrice Cousin 《World Journal of Stem Cells》 SCIE CAS 2011年第4期25-33,共9页
In adults, adipose tissue is abundant and can be easily sampled using liposuction. Largely involved in obesity and associated metabolic disorders, it is now described as a reservoir of immature stromal cells. These ce... In adults, adipose tissue is abundant and can be easily sampled using liposuction. Largely involved in obesity and associated metabolic disorders, it is now described as a reservoir of immature stromal cells. These cells, called adipose-derived stromal cells (ADSCs) must be distinguished from the crude stromal vascular fraction (SVF) obtained after digestion of adipose tissue. ADSCs share many features with mesenchymal stem cells derived from bone marrow, including paracrine activity, but they also display some specific features, including a greater angiogenic potential. Their angiogenic properties as well as their paracrine activity suggest a putative tumor-promoting role for ADSCs although contradictory data have been published on this issue. Both SVF cells and ADSCs are currently being investigated in clinical trials in several fields (chronic inflammation, ischemic diseases, etc. ). Apart from a phase Ⅲ trial on the treatment of fistula,most of these are in phaseⅠand use autologous cells. In the near future, the end results of these trials should provide a great deal of data on the safety of ADSC use. 展开更多
关键词 MESENCHYMAL stem CELLS Stroma CELLS Cell therapy White ADIPOSE tissue
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Thermal analysis as a microstructure prediction tool for A356 aluminium parts solidified under various cooling conditions 被引量:10
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作者 A.Niklas U.Abaunza +2 位作者 A.I.Fernández-Calvo J.Lacaze R.Suárez 《China Foundry》 SCIE CAS 2011年第1期89-95,共7页
Thermal analysis technique has been used for a long time,in both ferrous and nonferrous industries for evaluating the metallurgical quality of the liquid metal before casting.However,obtaining a proper microstructure ... Thermal analysis technique has been used for a long time,in both ferrous and nonferrous industries for evaluating the metallurgical quality of the liquid metal before casting.However,obtaining a proper microstructure in a standard cup does not ensure that the microstructure is correct in real parts which may solidify at very different cooling rates.For this study,alloy A356 with different metal quality in terms of modification and grain refinement was tested.Different cooling rates were obtained by using cylindrical test samples with various diameters cast in sand and metallic moulds.The correlation between microstructure features such as grain size,modification rate and secondary dendrite arm spacing (SDAS) measured in the standard thermal analysis cup with those obtained in the cylindrical test parts has been investigated.Thus,knowing the thermal modulus and the mould type it is possible to establish the required grain size and modification rate in the standard cup in order to get a desired structure in a real part.Corrective actions can then be taken in order to improve the metallurgical quality before casting the part. 展开更多
关键词 A356 aluminium alloy SOLIDIFICATION thermal analysis grain size modification rate
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Electrochemical ageing study of mixed lanthanum/praseodymium nickelates La2-xPrxNiO4+δ as oxygen electrodes for solid oxide fuel or electrolysis cells 被引量:6
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作者 Vaibhav Vibhu Aurélien Flura +5 位作者 Aline Rougier Clément Nicollet Sébastien Fourcade Teresa Hungria Jean-Claude Grenier Jean-Marc Bassat 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第7期62-70,I0003,共10页
The chemical and electrochemical stability of lanthanide nickelates La2 NiO4+δ(LNO),Pr2 NiO4+δ(PNO)and their mixed compounds La(2-x)PrxNiO4+δ(LPNOs)with x=0.5,1 or 1.5 is reported.The aim is to promote these materi... The chemical and electrochemical stability of lanthanide nickelates La2 NiO4+δ(LNO),Pr2 NiO4+δ(PNO)and their mixed compounds La(2-x)PrxNiO4+δ(LPNOs)with x=0.5,1 or 1.5 is reported.The aim is to promote these materials as efficient electrodes for solid oxide fuel cell(SOFC)and/or solid oxide electrolysis cell(SOEC).La2 NiO4+δand La1.5Pr0.5NiO4+δcompounds are chemically very stable as powders over one month in the temperature range 600-800℃,while the other materials rich in praseodymium progressively decompose into various perovskite-deriving components with additional Pr6 O11.Despite their uneven properties,all these materials are quite efficient and sustainable as electrodes on top of gadolinium doped ceria(GDCBL)//yttrium doped zirconia(8 YSZ)electrolyte,for one month at 700℃without polarization.Under polarization(300 mA·cm-2),the electrochemical performances of LNO,PNO and La1.5Pr0.5NiO4+δ(LP5 NO)quickly degrade in SOFC mode,i.e.for the oxygen reduction reaction,while they show durability in SOEC mode,i.e.for the oxide oxidation reaction. 展开更多
关键词 Lanthanide nickelates SOFC cathode SOEC anode Stability Inductive loop Degradation
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Corrosion rate determination of rare-earth Mg alloys in a Na_(2)SO_(4)solution by electrochemical measurements and inductive coupled plasma-optical emission spectroscopy 被引量:3
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作者 Samuel Leleu Bertrand Rives +1 位作者 Nicolas Causse Nadine Pébère 《Journal of Magnesium and Alloys》 SCIE EI CAS 2019年第1期47-57,共11页
The corrosion resistance of three Mg alloys containing rare-earth elements(WE43,EV31 and ZE41)was studied and compared to that of two Mg-Al alloys(AZ31 and AZ91)and of pure Mg(99.95 wt.%).Current-voltage curves and el... The corrosion resistance of three Mg alloys containing rare-earth elements(WE43,EV31 and ZE41)was studied and compared to that of two Mg-Al alloys(AZ31 and AZ91)and of pure Mg(99.95 wt.%).Current-voltage curves and electrochemical impedance measurements were performed with rotating disk electrodes in an aerated 0.1 M Na_(2)SO_(4)solution.For all the alloys,it was confirmed that the intermetallic particles acted as local cathodes and that more protective films were formed on the alloys surface by comparison with the pure Mg.Corrosion rates were determined from inductive coupled plasma-optical emission spectroscopy measurements and from the electrochemical measurements.Higher corrosion rates were observed for the rare-earth Mg alloys compared to the AZ series alloys.These data allowed the corrosion mechanisms to be discussed. 展开更多
关键词 Magnesium alloys Rare-earth elements EIS ICP-OES Interface
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Modelling of compacted graphite cast iron solidification-Discussion of microstructure parameters 被引量:2
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作者 Jacques Lacaze Urko de la Torre +1 位作者 Jon Sertucha Anna Regordosa 《China Foundry》 SCIE 2020年第2期144-149,共6页
A melt maintained for hours in a press pour unit allowed the following changes over time from spheroidal graphite to compacted graphite iron by casting thermal cups at regular time intervals.This provided extensive ex... A melt maintained for hours in a press pour unit allowed the following changes over time from spheroidal graphite to compacted graphite iron by casting thermal cups at regular time intervals.This provided extensive experimental information for checking the possibility of simulating solidification of compacted graphite irons by means of a microstructure modelling approach.During solidification,compacted graphite develops very much as lamellar graphite but with much less branching.On this basis,a simulation of the thermal analysis records was developed which considers solidification proceeding in a pseudo binary Fe-C system.The simulated curves were compared with the experimental ones obtained from three representative alloys that cover the whole microstructure change during the holding of the melt.The most relevant result is that the parameter describing branching capability of graphite is the most important for reproducing the minimum eutectic temperature and the recalescence which are so characteristic of the solidification of compacted graphite cast irons. 展开更多
关键词 COMPACTED GRAPHITE irons thermal analysis stable EUTECTIC METASTABLE EUTECTIC simulation
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Some paradoxical observations about spheroidal graphite degeneracy 被引量:1
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作者 Jacques Lacaze Jon Sertucha 《China Foundry》 SCIE 2018年第6期457-463,共7页
Differential thermal analysis experiments have been performed on samples machined from Y2-blocks cast with different high-silicon spheroidal graphite irons. Depending on magnesium, silicon, cerium and antimony content... Differential thermal analysis experiments have been performed on samples machined from Y2-blocks cast with different high-silicon spheroidal graphite irons. Depending on magnesium, silicon, cerium and antimony content, the as-cast microstructure showed various levels of chunky graphite in the central part of the blocks. In contrast, the microstructure of the materials after remelting and resolidification during differential thermal analysis consisted of lamellar or compacted graphite. The formation of chunky graphite in the as-cast microstructure is rationalized using an index or silicon equivalent that has been recently suggested. The differences in the microstructures after differential thermal analysis are discussed in terms of available free magnesium. Emphasis is finally put on the striking differences in characteristic size of the microstructures made of compacted graphite as compared to lamellar graphite and chunky graphite. This leads to tentative conclusions about growth of compacted and chunky graphite which would be worthy of further experimental investigations. 展开更多
关键词 high-silicon SPHEROIDAL GRAPHITE iron GRAPHITE DEGENERACY COMPACTED GRAPHITE chunky GRAPHITE
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Electro-Hydrodynamics and Kinetic Modeling of Dry and Humid Air Flows Activated by Corona Discharges 被引量:1
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作者 J. P. SARRETTE O. EICHWALD +2 位作者 F. MARCHAL O. DUCASSE M. YOUSFI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期469-472,共4页
The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor (ACDR) powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamenta... The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor (ACDR) powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour (humid air). The simulation involves the electro-dynamics~ chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post- discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone. 展开更多
关键词 DC corona discharge humid air chemistry plasma simulation NO treatment
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Electrochemical Degradation Mechanism of a Cermet Anode for Aluminum Production 被引量:2
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作者 P. Meyer L. Massot +4 位作者 M. Gibilaro S. Bouvet V. Laurent A. Marmottant P. Chamelot 《Materials Sciences and Applications》 2019年第9期614-629,共16页
Tests on (NixFeyO4 - Ni1?xFexO)/(CuxNiyFez) cermets, considered as promising anode for the aluminium production, were performed under electrolysis at 0.8 A·cm-2 in molten mixture of cryolite at 960°C. In ord... Tests on (NixFeyO4 - Ni1?xFexO)/(CuxNiyFez) cermets, considered as promising anode for the aluminium production, were performed under electrolysis at 0.8 A·cm-2 in molten mixture of cryolite at 960°C. In order to predict phase compositions, a thermodynamic study was performed and experimentally verified by SEM-EDS analysis. The metallic phase oxidation leads to the formation of different phases such as FeF2, Ni0.90Fe0.10O, NiF2 and Cu2O phases, while NixFe3-xO4 spinel is continuously enriched up to x = 0.90, the thermodynamically stable nickel composition. When the cermet material is fully oxidized, metallic and oxide phases are converted into soluble or non-conductive phases, leading to the end of anode service life. 展开更多
关键词 Metal/Oxide Electrode Aluminium ELECTROLYSIS Oxidation Reaction Mechanism
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Weaning-associated feed deprivation stress causes microbiota disruptions in a novel mucin-containing in vitro model of the piglet colon(MPigut-IVM) 被引量:1
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作者 Raphaële Gresse Frédérique Chaucheyras-Durand +4 位作者 Sylvain Denis Martin Beaumont Tom Van de Wiele Evelyne Forano Stéphanie Blanquet-Diot 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第4期1428-1450,共23页
Background:Risk factors for the etiology of post-weaning diarrhea,a major problem in swine industry associated with enormous economic losses,remain to be fully elucidated.In concordance with the ethical concerns raise... Background:Risk factors for the etiology of post-weaning diarrhea,a major problem in swine industry associated with enormous economic losses,remain to be fully elucidated.In concordance with the ethical concerns raised by animal experiments,we developed a new in vitro model of the weaning piglet colon(MPigut-IVM)including a mucin bead compartment to reproduce the mucus surface from the gut to which gut microbes can adhere.Results:Our results indicated that the MPigut-IVM is able to establish a representative piglet archaeal and bacterial colon microbiota in terms of taxonomic composition and function.The MPigut-IVM was consequently used to investigate the potential effects of feed deprivation,a common consequence of weaning in piglets,on the microbiota.The lack of nutrients in the MPigut-IVM led to an increased abundance of Prevotellaceae and Escherichia-Shigella and a decrease in Bacteroidiaceae and confirms previous in vivo findings.On top of a strong increase in redox potential,the feed deprivation stress induced modifications of microbial metabolite production such as a decrease in acetate and an increase in proportional valerate,isovalerate and isobutyrate production.Conclusions:The MPigut-IVM is able to simulate luminal and mucosal piglet microbiota and represent an innovative tool for comparative studies to investigate the impact of weaning stressors on piglet microbiota.Besides,weaning-associated feed deprivation in piglets provokes disruptions of MPigut-IVM microbiota composition and functionality and could be implicated in the onset of post-weaning dysbiosis in piglets. 展开更多
关键词 Colon DYSBIOSIS In vitro gut model MICROBIOTA MUCIN Piglet Weaning
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Interaction between Live Yeast and Dietary Rumen Degradable Protein Level: Effects on Diet Utilization in Early-Lactating Dairy Cows 被引量:2
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作者 Christine Julien Jean Philippe Marden +4 位作者 Eric Auclair Raymond Moncoulon Laurent Cauquil Jean Louis Peyraud Corine Bayourthe 《Agricultural Sciences》 2015年第1期1-13,共13页
Four early lactating Holstein cows were used to study the effect of live yeast (LY, Actisaf&reg;CNCM I-4407, Lesaffre Feed Additives, Marcq en Baroeul, France) supplementation on diet digestive utilization of dair... Four early lactating Holstein cows were used to study the effect of live yeast (LY, Actisaf&reg;CNCM I-4407, Lesaffre Feed Additives, Marcq en Baroeul, France) supplementation on diet digestive utilization of dairy cows receiving concentrated corn silage-based diets with two rumen-degradable protein (RDP) levels. For a 33 d period, cows were fed a total mixed ration (TMR) containing an adequate level (AL) of RDP or a low level (LL, 30% below AL) by using soybean meal or tanned soybean meal, respectively: for 21 d with no LY addition followed by 12 d during which LY was added to the diet. The pH and redox potential (Eh) were recorded and ruminal fluid samples were collected over 3 consecutive days. Feces were collected individually over 48 h and individual dry matter intake (DMI) was measured for determining apparent nutrient digestibility. The effective degradability of individual feed ingredients composing both diets was evaluated with nylon bags technique. Structure of the ruminal bacterial community was studied and diversity index was calculated. Digestibility of organic matter (OM) and crude protein (CP) were lower for LL than those for AL. With LY, digestibility of OM and CP was increased: +2.4 and +0.8 points, for AL, and +3.7 and +5.9 points for LL, respectively. Live yeast reduced dietary N ruminal degradation with both AL and LL. Ruminal pH and Eh were lower with AL compared to LL: 5.95 and –167 mV vs. 6.13 and –144 mV. Live yeast increased ruminal total volatile fatty acids (VFA) (+8.6%), C2 (+10%), and C4 (+35%) contents for LL and decreased that of C3 (?9.8%) for AL. Neither the structure of bacterial populations of the rumen nor the diversity index (Shannon) was altered by treatments. Those results suggested a specific interest in using LY in RDP deficient diets for early lactating cows. 展开更多
关键词 DAIRY COW LIVE YEAST Nitrogen DIGESTION Ruminally DEGRADABLE Protein
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Effects of Feeding Programs Based on One or Two Milk Replacer Daily Meals on Growth, Solid Feed Intake and Rumen Fermentation and Development of Dairy Calves 被引量:2
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作者 Christine Julien Corine Bayourthe +1 位作者 Caroline Lacroux Francis Enjalbert 《Agricultural Sciences》 2015年第12期1428-1440,共13页
Sixteen Holstein calves were used to study the effects of two feeding programs (FP) on growth, intake, rumen development and ruminal metabolism from birth to weaning. Two feeding programs based on milk replacer (MR) w... Sixteen Holstein calves were used to study the effects of two feeding programs (FP) on growth, intake, rumen development and ruminal metabolism from birth to weaning. Two feeding programs based on milk replacer (MR) were tested: a once a day (OAD) MR (200 g/L) distribution vs. a standard twice a day (TAD) MR (125 g/L) distribution. All calves received water, wheat straw and a starter concentrate ad libitum. Four calves per group were slaughtered at weaning and rumen epithelium from the ventral sac was sampled for papillae (RP) density. Results showed that the FP had no effect on body weight of calves and total feed intake. From day 42 to day 56, ruminal pH was lower (P = 0.036) and ruminal oxydo-reducing potential was higher (P = 0.001) in OAD than TAD calves. Ruminal total volatile fatty acid (VFA) concentrations did not significantly differ between FP. From day 21 to day 63, butyrate ruminal concentration was significantly higher in OAD than TAD calves (5.17 vs 3.95 mmol/L). This probably explained the higher development of RP in calves fed once daily. Finally, the tested feeding system based on a once daily MR distribution affects the concentrate feeding pattern of calves. 展开更多
关键词 DAIRY CALVES MILK Replacer FEEDING Frequency Oxydo-Reducing Potential RUMEN DEVELOPMENT
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Kinetic Modeling of Isothermal or Non-isothermal Adsorption in a Pellet:Application to Adsorption Heat Pumps 被引量:1
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作者 Ludovic Montastruc Pascal Floquet +2 位作者 Volker Mayer Iordan Nikov Serge Domenech 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第4期544-553,共10页
Understanding the interaction between a fluid and a solid phase is of fundamental importance to the design of an adsorption process.Because the heat effects associated with adsorption are comparatively large,the as-su... Understanding the interaction between a fluid and a solid phase is of fundamental importance to the design of an adsorption process.Because the heat effects associated with adsorption are comparatively large,the as-sumption of isothermal behavior is a valid approximation only when uptake rates are relatively slow.In this article,we propose to determine when it is needed to choose the isothermal or non-isothermal assumption according to two physical parametersα(ratio convection/capacity) andβ(quantity of energy/capacity) .The proposed problem is solved by a mathematical method in the Laplace domain.Whenα→∞(infinitely high heat transfer coefficient) or β→0(infinitely large heat capacity) ,the limiting case is isothermal.When the diffusion is rapid(α10) the kinetics of sorption is controlled entirely by heat transfer.If the adsorption process is to be used as a heat pump,it shall be represented by an isotherm model withαandβas high as possible. 展开更多
关键词 ADSORPTION NON-ISOTHERMAL ENERGY PELLET
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Characterization and photoluminescence properties of ultrafine copper molybdate(α-CuMoO_4) powders prepared via a combustion-like process 被引量:2
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作者 Mohamed Benchikhi Rachida El Ouatib +2 位作者 Sophie Guillemet-Fritsch Lahcen Er-Rakho Bernard Durand 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第11期1340-1345,共6页
We report a simple method for preparing copper(II) molybdate(CuMoO_4) powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing... We report a simple method for preparing copper(II) molybdate(CuMoO_4) powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the(CuMo)-precursor gel was studied by thermogravimetry–differential thermal analysis(TG–DTA), Fourier transform infrared spectroscopy(FTIR), and X-ray diffraction(XRD). We observed that the crystallization of CuMoO_4 powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m^2/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO_4 crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO_4^(2-)] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size. 展开更多
关键词 copper molybdate chemical synthesis photoluminescence Jahn-Teller effect
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Allium sativum Flavor Compounds as an Indicator for Garlic Identity and Quality Determination 被引量:1
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作者 Ruta Galoburda Karina Bodniece Thierry Talou 《Journal of Food Science and Engineering》 2013年第5期226-234,共9页
The objective of the study was to research the aroma profile of volatile compounds in garlic subspecies originating from Latvia, and compare them with the aroma composition of garlic grown in the region of Midi-Pyrene... The objective of the study was to research the aroma profile of volatile compounds in garlic subspecies originating from Latvia, and compare them with the aroma composition of garlic grown in the region of Midi-Pyrenees (France). It was established that hard-neck garlic tends to contain more diallyl disulfide (DADS), the main decomposition product of allicin. Compared to the hard-neck subspecies, the content of allyl mercaptan, one of the major compounds producing the strong odor detectable after ingestion of garlic, was significantly lower in the soft-neck garlic clones. The amount of cyclic compound 3-vinyl-1,2-dithiin differed considerably with higher contents in the soft-neck subspecies. The results also demonstrate the soft-neck garlic as a more suitable subspecies for long-term storage. In general, the results show no significant difference in the content of DADS and the total content of other flavor compounds between hard-neck and soft-neck garlic grown in the region of Midi-Pyrenees and Latvia. However, comparing garlic subspecies originating from France and Latvia by the content of allyl mercaptan, 1,2-dithiolane and 3-vinyl-1,2-dithiin, a considerable proportional difference of these volatiles was determined. Also, a significant difference was established in the content of DADS between the white garlic variety "Blanc de Lomagne" (France, region of Midi-Pyrenees) and white garlic grown in other countries. The results of this study suggest the suitability of solid phase microextraction (SPME) and gas chromatography (GC) methods for quality control of garlic originating from France. 展开更多
关键词 Allium sativum diallyl disulfide FLAVOR GARLIC IDENTITY
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