By and large the research communities today are not fully aware of the remarkable universality in the dynamic properties of many-body relaxation/diffusion processes manifested in experiments and simulations on condens...By and large the research communities today are not fully aware of the remarkable universality in the dynamic properties of many-body relaxation/diffusion processes manifested in experiments and simulations on condensed matter with diverse chemical compositions and physical structures. I shall demonstrate the universality first from the dynamic processes in glass-forming systems. This is reinforced by strikingly similar properties of different processes in contrasting interacting systems all having nothing to do with glass transition. The examples given here include glass-forming systems of diverse chemical compositions and physical structures, conductivity relaxation of ionic conductors（liquid, glassy, and crystalline）,translation and orientation ordered phase of rigid molecule, and polymer chain dynamics. Universality is also found in the change of dynamics when dimension is reduced to nanometer size in widely different systems. The remarkable universality indicates that many-body relaxation/diffusion is governed by fundamental physics to be unveiled. One candidate is classical chaos on which the coupling model is based, Universal properties predicted by this model are in accord with diverse experiments and simulations.展开更多
The injection of a high pressure gas into a stagnant liquid pool is the characteristic phenomenon during the expansion phase of a hypothetical core disruptive accident in liquid metal cooled fast reactors. In order to...The injection of a high pressure gas into a stagnant liquid pool is the characteristic phenomenon during the expansion phase of a hypothetical core disruptive accident in liquid metal cooled fast reactors. In order to investigate lots of mechanisms involved in this phase of the accident＇s evolution, an experimental campaign called S GI was performed in 1994 in Forschungszentrum Karlsruhe, now KIT. This campaign consists of nine experiments which have been dedicated to assess the effects of different pressure injection, the nozzle＇s size and the presence of inner confinement in the formation of the rising bubble. Three of these experiments, which were focused on the pressure effects, have now been simulated with SIMMER III code and with FLUENT 6.3, a commercial CFD code. Both codes, despite their different features, have showed a good agreement with the experimental results. In particular, time trend evolutions of pressures and bubble volumes have been well reproduced by simulation. Furthermore, both codes agree on the shape of the bubble, even though they have evidenced same discrepancies with the experimental shape.展开更多
The use of a broadband, frequency shaped femtosecond laser on translationally cold cesium molecules has recently demonstrated to be a very efficient method of cooling also the vibrational degree of freedom. A sample o...The use of a broadband, frequency shaped femtosecond laser on translationally cold cesium molecules has recently demonstrated to be a very efficient method of cooling also the vibrational degree of freedom. A sample of cold molecules, initially distributed over several vibrational levels, has thus been transfered into a single selected vibrational level of the singlet X^1∑g ground electronic state. Our method is based on repeated optical pumping by laser light with a spectrum broad enough to excite all populated vibrational levels but limited in its frequency bandwidth with a spatial light modulator. In such a way we are able to eliminate transitions from the selected level, in which molecules accumulate. In this paper we briefly report the main experimental results and then address, in a detailed way by computer simulations, the perspectives for a ＂complete＂ cooling of the molecules, including also the rotational degree of freedom. Since the pumping process strongly depends on the relative shape of the ground and excited potential curves, ro-vibrational cooling through different excited states is theoretically compared.展开更多
Objective:To investigate clinicopathological,bacteriological and pathological aspects of an experimental infection with Yersinia pseudotuberculosis(Y.pseudotuberculosis)in hares in order to verify the efficacy of sero...Objective:To investigate clinicopathological,bacteriological and pathological aspects of an experimental infection with Yersinia pseudotuberculosis(Y.pseudotuberculosis)in hares in order to verify the efficacy of serology for the in vivo diagnosis.Moreover,the pathogenicity of two Y.pseudotuberculosis strains was investigated in order to detect potential differences.Methods:Twelve European brown hares(Lepus europaeus,Pallas)were experimentally infected per os and via conjunctival mucosae with Y.pseudotuberculosis:six subjects were infected with a strain isolated from a naturally infected hare(YpH)and six subjects with a strain isolated from a naturally infected rabbit(YpR).Two hares were used as negative controls.All animals were subjected to clinical,bacteriological and serological examinations during 9 weeks following the infection and,at the end of the control period,subjects still alive were euthanized and submitted to a complete post mortem examination.Results:All faecal samples collected during the control period were positive for bacteriological examinations and to a PCR for the inv gene of Y.pseudotuberculosis,while only one Yp H-infected hare showed a positive haemocultures.From the 2nd to the 9th week post infection(pi),serological analysis revealed specific antibodies with titers ranging from 1:10 to 1:160 in all YpH-infected and two YpR-infected subjects.All the Yp H-infected and two Yp R-infected hares scored positive for Y.pseudotuberculosis by means of bacteriological investigations.Grossly,suppurative multifocal lesions were detected in liver,spleen,kidney and sub-mandibular lymph nodes in both YpH-and YpR-infected hares and confirmed with histopathology.Pulmonary lesions were observed only in Yp H-infected subjects.Immunohistochemistry confirmed the presence of bacterial antigen in all infected animals.Conclusion:Results of this study revealed that YpH strain is more pathogenic for hares than the YpR strain;moreover the serological test performed in this study could be used for the diagnosis of pseudotuberculosis in hares,whereas post mortem diagnosis should be confirmed by means of bacteriological examination,PCR,histopathology and immunohistochemistry.展开更多
The chemical composition of the essential oil obtained by hydrodistillation from the leaves of Phyllanthus reticulatus Poiret (Euphorbiaceae) growing in Nigeria has been studied. The constituents of the oil were analy...The chemical composition of the essential oil obtained by hydrodistillation from the leaves of Phyllanthus reticulatus Poiret (Euphorbiaceae) growing in Nigeria has been studied. The constituents of the oil were analyzed by means of gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Monoterpenes (64.9%) were the dominant class of compounds, followed by sesquiterpenes (23.0%). The major constituents were α-pinene (6.0%), sabinene (7.6%), β-pinene (18.1%), linalool (6.9%) and camphor (7.7%), among the monoterpenes, and β-caryophyllene (11.9%) and germacrene D (8.6%) among the sesquiterpenes. This is the first report on the volatile constituents of Phyllanthus reticulatus.展开更多
White lasers are becoming increasingly relevant in various fields since they exhibit unprecedented properties in terms of beam brightness and intensity modulation.Here we introduce a white laser based on a polymer mat...White lasers are becoming increasingly relevant in various fields since they exhibit unprecedented properties in terms of beam brightness and intensity modulation.Here we introduce a white laser based on a polymer matrix encompassing liquid crystals and multiple organic chromophores in a multifunctional phase-separation system.The separation of the hydrophilic matrix and the hydrophobic liquid crystals leads to the formation of a complex optically active layer,featuring lasing emission tuneable from blue to red.White laser emission is found with an optical excitation threshold of approximately 12 mJ/cm^(2).Importantly,an external electric field can be used to control the device emission intensity.White lasers with low-voltage(≤10 V)controllable emission might pave the way for a new generation of broadband light sources for analytical,computational,and communication applications.展开更多
CONSPECTUS:The realization of intelligent,self-powered compo-nents and devices exploiting the piezoelectric effect at large scale might greatly contribute to improve our efficiency in using resources,albeit a profound...CONSPECTUS:The realization of intelligent,self-powered compo-nents and devices exploiting the piezoelectric effect at large scale might greatly contribute to improve our efficiency in using resources,albeit a profound redesign of the materials and architectures used in current electronic systems would be necessary.Piezoelectricity is a property of certain materials to generate an electrical bias in response to a mechanical deformation.This effect enables energy to be harvested from strain and vibration modes,and to sustain the power of actuators,transducers,and sensors in integrated networks,such as those necessary for the Internet of Thing.展开更多
In this paper the authors present a derivation of a back-scatter rotational Large Eddy Simulation model,which is the extension of the Baldwin&Lomax model to nonequilibrium problems.The model is particularly design...In this paper the authors present a derivation of a back-scatter rotational Large Eddy Simulation model,which is the extension of the Baldwin&Lomax model to nonequilibrium problems.The model is particularly designed to mathematically describe a fluid filling a domain with solid walls and consequently the differential operators appearing in the smoothing terms are degenerate at the boundary.After the derivation of the model,the authors prove some of the mathematical properties coming from the weighted energy estimates,which allow to prove existence and uniqueness of a class of regular weak solutions.展开更多
The enantiomers of carboline-based cryptates were successfully resolved by chiral HPLC.These complexes show high configurational stability under harsh conditions and their absolute configuration was determined by comp...The enantiomers of carboline-based cryptates were successfully resolved by chiral HPLC.These complexes show high configurational stability under harsh conditions and their absolute configuration was determined by comparing theoretical and expe rimental electronic circular dichroism spectra.The e nantiopure cryptates exhibit strong circularly polarized luminescence with a maximum dissymmetry factor glum=0.25 for the f-f transition 5 D0→7 F1(λ=594 nm)under visible light excitation atλgx=400 nm.展开更多
We investigate the tunnel coupling between the outer p-type GaAsSb shell and the n-type InAs core in catalyst-free InAs/lnP/GaAsSb core-dualshell nanowires.We present a device fabrication protocol based on wet-etching...We investigate the tunnel coupling between the outer p-type GaAsSb shell and the n-type InAs core in catalyst-free InAs/lnP/GaAsSb core-dualshell nanowires.We present a device fabrication protocol based on wet-etching processes on selected areas of the nanostructures that enables multiple configurations of measurements in the same nanowire-based device(i.e.shell-shell,core-core and core-shell).Low-temperature(4.2 K)transport in the shell-shell configuration in nanowires with 5 nm-thick InP barrier reveals a weak negative differential resistance.Differently,when the InP barrier thickness is increased to 10 nm,this negative differential resistance is fully quenched.The electrical resistance between the InAs core and the GaAsSb shell,measured in core-shell configuration,is significantly higher with respect to the resistance of the InAs core and of the GaAsSb shell.The field effect,applied via a back-gate,has an opposite impact on the electrical transport in the core and in the shell portions.Our results show that electron and hole free carriers populate the InAs and GaAsSb regions respectively and indicate InAs/InP/GaAsSb core-dualshell nanowires as an ideal system for the investigation of the physics of interacting electrons and holes at the nanoscale.展开更多
A standard assumption when modelling linked sample data is that the stochastic properties of the linking process and process underpinning the population values of the response variable are independent of one another.T...A standard assumption when modelling linked sample data is that the stochastic properties of the linking process and process underpinning the population values of the response variable are independent of one another.This is often referred to as non-informative linkage.But what if linkage errors are informative?In this paper,we provide results from two simulation experiments that explore two potential informative linking scenarios.The first is where the choice of sample record to link is dependent on the response;and the second is where the probability of correct linkage is dependent on the response.We focus on the important and widely applicable problem of estimation of domain means given linked data,and provide empirical evidence that while standard domain estimation methods can be substantially biased in the presence of informative linkage errors,an alternative estimation method,based on a Gaussian approximation to a maximum likelihood estimator that allows for non-informative linkage error,performs well.展开更多
Femoral glands of male lizards produce waxy secretions that are involved in inter- and intraspecific chemical communication. The main components of these secretions are proteins and lipids, the latter having been exte...Femoral glands of male lizards produce waxy secretions that are involved in inter- and intraspecific chemical communication. The main components of these secretions are proteins and lipids, the latter having been extensively studied and already associated to male quality. On the opposite, the composition and role of proteins are nearly unknown, the only available information coming from few studies on iguanids. These studies got the conclusion that proteins might have a communicative function, notably they could signal individual identity. A generalization of these findings requires the extension of protein analysis to other lizard families, and the primary detection of some patterns of individual variability. Using the common wall lizard Podarcis muralis as a model species, the protein fraction of the femoral pore secretions was investigated to provide the first characterization of this component in a lacertid lizard and to explore its source of variability, as a first step to support the hypothesized communicative role. Samples of proteins from femoral secretions were collected from 6 Italian populations and subjected to 1-dimensional electrophoresis. The binary vector of the band presence/absence was used to define the individual profiles. Protein fraction is found to have a structured pattern, with both an individual and a population component. Although the former supports the potential communicative role of proteins, the latter offers a double interpretation, phylogenetic or environmental, even though the phylogenetic effect seems more likely given the climatic resemblance of the considered sites. Further studies are necessary to shed light on both these issues.展开更多
Magnesium(Mg)implants have shown to cause image artefacts or distortions in magnetic resonance imaging(MRI).Yet,there is a lack of information on how the degradation of Mg-based implants influences the image quality o...Magnesium(Mg)implants have shown to cause image artefacts or distortions in magnetic resonance imaging(MRI).Yet,there is a lack of information on how the degradation of Mg-based implants influences the image quality of MRI examinations.In this study,Mg-based implants are analysed in vitro,ex vivo,and in the clinical setting for various magnetic field strengths with the aim to quantify metallic artefact behaviour.In vitro corroded Mg-based screws and a titanium(Ti)equivalent were imaged according to the ASTM F2119.Mg-based and Ti pins were also implanted into rat femurs for different time points and scanned to provide insights on the influence of soft and hard tissue on metallic artefact.Additionally,MRI data of patients with scaphoid fractures treated with CE-approved Mg-based compression screws(MAGNEZIX®)were analysed at various time points post-surgery.The artefact production of the Mg-based material decreased as implant material degraded in all settings.The worst-case imaging scenario was determined to be when the imaging plane was selected to be perpendicular to the implant axis.Moreover,the Mg-based implant outperformed the Ti equivalent in all experiments by producing lower metallic artefact(p<0.05).This investigation demonstrates that Mg-based implants generate significantly lower metallic distortion in MRI when compared to Ti.Our positive findings suggest and support further research into the application of Mg-based implants including post-operative care facilitated by MRI monitoring of degradation kinetics and bone/tissue healing processes.展开更多
In order to reveal the nature of dark matter,it is crucial to detect its non-gravitational interactions with the standard model particles.The traditional dark matter searches focused on the so-called weakly interactin...In order to reveal the nature of dark matter,it is crucial to detect its non-gravitational interactions with the standard model particles.The traditional dark matter searches focused on the so-called weakly interacting massive particles.However,this paradigm is strongly constrained by the null results of current experiments with high precision.Therefore there is a renewed interest of searches for heavy dark matter particles above TeV scale.The Large High Altitude Air Shower Observatory(LHAASO)with large effective area and strong background rejection power is very suitable to investigate the gamma-ray signals induced by dark matter annihilation or decay above TeV scale.In this document,we review the theoretical motivations and background of heavy dark matter.We review the prospects of searching for the gamma-ray signals resulted from dark matter in the dwarf spheroidal satellites and Galactic halo for LHAASO,and present the projected sensitivities.We also review the prospects of searching for the axion-like particles,which are a kind of well motivated light pseudo-scalars,through the LHAASO measurement of the very high energy gamma-ray spectra of astrophysical sources.展开更多
The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse mome...The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse momentum, PT, and rapidity, y. The kinematic region of the measurements is pT〈20 GeV/c and 2.0 〈g〈4.5.The measurements use a data sample corresponding to an integrated luminosity of 3fb-1 collected by the LHCb detector in pp collisions at centre-of-mass energies √s=7 TeV in 2011 and √s=8 TeV in 2012. Based on previous LHCb results of the fragmentation fraction ratio,f∧0/b/fd,the branching fraction of the decay ∧0/b→ J/ψ pK-is measured to be B（∧0/b→ J/ψ pK-）=（3.17±0.04±0.07±0.34＋0.45/-0.28）×10-4,where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay -B/0 →J/ψ-K＊（892）0,and the fourth is due to the knowledge of f∧0/b/fd.The sum of the asymmetries in the production and decay between ∧0/b and ∧0/bis also measured as a function of PT and y.The previously published branching fraction of ∧0/b→ J/ψ pπ-,relative to that of ∧0/b→ J/ψ pK-,is updated. The branching fractions of ∧0/b→P＋c（→ J/ψp）K-are determined.展开更多
A search for the doubly charmed baryon ■^+cc is performed through its decay to theΛ^+c K^-π^+ final state,using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7,8 and 13...A search for the doubly charmed baryon ■^+cc is performed through its decay to theΛ^+c K^-π^+ final state,using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7,8 and 13 TeV.The data correspond to a total integrated luminosity of 9 fb^-1.No significant signal is observed in the mass range from 3.4 to 3.8 GeV/c^2.Upper limits are set at 95%credibility level on the ratio of the ■^+cc production cross-section times the branching fraction to that ofΛ^+c and ■^++cc baryons.The limits are determined as functions of the ■^+cc mass for different lifetime hypotheses,in the rapidity range from 2.0 to 4.5 and the transverse momentum range from 4 to 15 GeV/c.展开更多
A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No signific...A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No significant signal of the decay is observed and an upper limitof 1.1x 10^(-7)at 90%confidence level is set on the branching fraction.展开更多
The first search for the doubly heavyΩ^(0)_(bc)baryon and a search for the E^(0)_(bc)baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 T...The first search for the doubly heavyΩ^(0)_(bc)baryon and a search for the E^(0)_(bc)baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 TeV,corresponding to an integrated luminosity of 5.2 fb^(-1).The baryons are reconstructed via their decays to Λ^(+)_(c)π^(-)and E^(+)_(c)π^(-).No significant excess is fbund for invariant masses between 6700 and 7300 MeV/c^(2),in a rapidity range from 2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/c.Upper limits are set on the ratio of the Ω^(0)_(bc)and E^(0)_(bc)production cross-section times the branching fraction to Λ^(+)_(c)π^(-)(E^(+)_(c)π^(-))relative to that of the Λ^(0)_(b)(E^(0)_(b))baryon,for different lifetime hypotheses,at 95%confidence level.The upper limits range from 0.5 x 10^(-4)to 2.5 x 10^(-4)for theΩ^(0)_(bc)→Λ^(+)_(c)π^(-)(E^(0)_(bc)→Λ^(+)_(c)π^(-))decay,and from 1.4x 10^(-3)to 6.9 x 10^(-3)for theΩ^(0)_(bc)→E^(+)_(c)π^(-)(E^(0)_(bc)→E^(+)_(c)π^(-))decay,depending on the considered mass and lifetime of theΩ^(0)_(bc)(E^(0)_(bc))baryon.展开更多
文摘By and large the research communities today are not fully aware of the remarkable universality in the dynamic properties of many-body relaxation/diffusion processes manifested in experiments and simulations on condensed matter with diverse chemical compositions and physical structures. I shall demonstrate the universality first from the dynamic processes in glass-forming systems. This is reinforced by strikingly similar properties of different processes in contrasting interacting systems all having nothing to do with glass transition. The examples given here include glass-forming systems of diverse chemical compositions and physical structures, conductivity relaxation of ionic conductors（liquid, glassy, and crystalline）,translation and orientation ordered phase of rigid molecule, and polymer chain dynamics. Universality is also found in the change of dynamics when dimension is reduced to nanometer size in widely different systems. The remarkable universality indicates that many-body relaxation/diffusion is governed by fundamental physics to be unveiled. One candidate is classical chaos on which the coupling model is based, Universal properties predicted by this model are in accord with diverse experiments and simulations.
文摘The injection of a high pressure gas into a stagnant liquid pool is the characteristic phenomenon during the expansion phase of a hypothetical core disruptive accident in liquid metal cooled fast reactors. In order to investigate lots of mechanisms involved in this phase of the accident＇s evolution, an experimental campaign called S GI was performed in 1994 in Forschungszentrum Karlsruhe, now KIT. This campaign consists of nine experiments which have been dedicated to assess the effects of different pressure injection, the nozzle＇s size and the presence of inner confinement in the formation of the rising bubble. Three of these experiments, which were focused on the pressure effects, have now been simulated with SIMMER III code and with FLUENT 6.3, a commercial CFD code. Both codes, despite their different features, have showed a good agreement with the experimental results. In particular, time trend evolutions of pressures and bubble volumes have been well reproduced by simulation. Furthermore, both codes agree on the shape of the bubble, even though they have evidenced same discrepancies with the experimental shape.
文摘The use of a broadband, frequency shaped femtosecond laser on translationally cold cesium molecules has recently demonstrated to be a very efficient method of cooling also the vibrational degree of freedom. A sample of cold molecules, initially distributed over several vibrational levels, has thus been transfered into a single selected vibrational level of the singlet X^1∑g ground electronic state. Our method is based on repeated optical pumping by laser light with a spectrum broad enough to excite all populated vibrational levels but limited in its frequency bandwidth with a spatial light modulator. In such a way we are able to eliminate transitions from the selected level, in which molecules accumulate. In this paper we briefly report the main experimental results and then address, in a detailed way by computer simulations, the perspectives for a ＂complete＂ cooling of the molecules, including also the rotational degree of freedom. Since the pumping process strongly depends on the relative shape of the ground and excited potential curves, ro-vibrational cooling through different excited states is theoretically compared.
文摘Objective:To investigate clinicopathological,bacteriological and pathological aspects of an experimental infection with Yersinia pseudotuberculosis(Y.pseudotuberculosis)in hares in order to verify the efficacy of serology for the in vivo diagnosis.Moreover,the pathogenicity of two Y.pseudotuberculosis strains was investigated in order to detect potential differences.Methods:Twelve European brown hares(Lepus europaeus,Pallas)were experimentally infected per os and via conjunctival mucosae with Y.pseudotuberculosis:six subjects were infected with a strain isolated from a naturally infected hare(YpH)and six subjects with a strain isolated from a naturally infected rabbit(YpR).Two hares were used as negative controls.All animals were subjected to clinical,bacteriological and serological examinations during 9 weeks following the infection and,at the end of the control period,subjects still alive were euthanized and submitted to a complete post mortem examination.Results:All faecal samples collected during the control period were positive for bacteriological examinations and to a PCR for the inv gene of Y.pseudotuberculosis,while only one Yp H-infected hare showed a positive haemocultures.From the 2nd to the 9th week post infection(pi),serological analysis revealed specific antibodies with titers ranging from 1:10 to 1:160 in all YpH-infected and two YpR-infected subjects.All the Yp H-infected and two Yp R-infected hares scored positive for Y.pseudotuberculosis by means of bacteriological investigations.Grossly,suppurative multifocal lesions were detected in liver,spleen,kidney and sub-mandibular lymph nodes in both YpH-and YpR-infected hares and confirmed with histopathology.Pulmonary lesions were observed only in Yp H-infected subjects.Immunohistochemistry confirmed the presence of bacterial antigen in all infected animals.Conclusion:Results of this study revealed that YpH strain is more pathogenic for hares than the YpR strain;moreover the serological test performed in this study could be used for the diagnosis of pseudotuberculosis in hares,whereas post mortem diagnosis should be confirmed by means of bacteriological examination,PCR,histopathology and immunohistochemistry.
文摘The chemical composition of the essential oil obtained by hydrodistillation from the leaves of Phyllanthus reticulatus Poiret (Euphorbiaceae) growing in Nigeria has been studied. The constituents of the oil were analyzed by means of gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Monoterpenes (64.9%) were the dominant class of compounds, followed by sesquiterpenes (23.0%). The major constituents were α-pinene (6.0%), sabinene (7.6%), β-pinene (18.1%), linalool (6.9%) and camphor (7.7%), among the monoterpenes, and β-caryophyllene (11.9%) and germacrene D (8.6%) among the sesquiterpenes. This is the first report on the volatile constituents of Phyllanthus reticulatus.
基金funding from the European Research Council under the European Union’s Horizon 2020 Research and Innovation Programme(Grant Agreement no.682157,“xPRINT”)the support from the project PRA_2018_34(“ANISE”)+4 种基金from the University of Pisa and from the project PRIN 2017PHRM8X(“3D-Phys”)from the Italian Minister of University and Researchthe support from the Foundation for Polish Science(FNP)the support of The National Science Center,Poland(2018/31/B/ST8/02832)of the Wroclaw University of Science and Technology.
文摘White lasers are becoming increasingly relevant in various fields since they exhibit unprecedented properties in terms of beam brightness and intensity modulation.Here we introduce a white laser based on a polymer matrix encompassing liquid crystals and multiple organic chromophores in a multifunctional phase-separation system.The separation of the hydrophilic matrix and the hydrophobic liquid crystals leads to the formation of a complex optically active layer,featuring lasing emission tuneable from blue to red.White laser emission is found with an optical excitation threshold of approximately 12 mJ/cm^(2).Importantly,an external electric field can be used to control the device emission intensity.White lasers with low-voltage(≤10 V)controllable emission might pave the way for a new generation of broadband light sources for analytical,computational,and communication applications.
基金supported by the European Commission’s Marie Skłodowska-Curie Actions(MSCA),through the Marie Skłodowska-Curie Individual Fellowship(896811BIOIMDH2020-MSCA-IF-2019)support from the PRIN 20173L7W8K project funded by Italian Minister of Research.
文摘CONSPECTUS:The realization of intelligent,self-powered compo-nents and devices exploiting the piezoelectric effect at large scale might greatly contribute to improve our efficiency in using resources,albeit a profound redesign of the materials and architectures used in current electronic systems would be necessary.Piezoelectricity is a property of certain materials to generate an electrical bias in response to a mechanical deformation.This effect enables energy to be harvested from strain and vibration modes,and to sustain the power of actuators,transducers,and sensors in integrated networks,such as those necessary for the Internet of Thing.
基金supported by the group GNAMPA of INd AM and the University of Pisa,under grantPRA 201852 UNIPI。
文摘In this paper the authors present a derivation of a back-scatter rotational Large Eddy Simulation model,which is the extension of the Baldwin&Lomax model to nonequilibrium problems.The model is particularly designed to mathematically describe a fluid filling a domain with solid walls and consequently the differential operators appearing in the smoothing terms are degenerate at the boundary.After the derivation of the model,the authors prove some of the mathematical properties coming from the weighted energy estimates,which allow to prove existence and uniqueness of a class of regular weak solutions.
基金Project supported by the German Research Foundation(DFG,research grant SE1448/7-1 for M.S.)German Academic Scholarship Foundation(Studienstiftung des deutsches Volkes,predoctoral fellowship for E.K.)。
文摘The enantiomers of carboline-based cryptates were successfully resolved by chiral HPLC.These complexes show high configurational stability under harsh conditions and their absolute configuration was determined by comparing theoretical and expe rimental electronic circular dichroism spectra.The e nantiopure cryptates exhibit strong circularly polarized luminescence with a maximum dissymmetry factor glum=0.25 for the f-f transition 5 D0→7 F1(λ=594 nm)under visible light excitation atλgx=400 nm.
基金This research activity was partially supported by the SUPERTOP project,QUANTERA ERA-NET Cofound in Quantum Technologies,and by the FET-OPEN project AndQC.
文摘We investigate the tunnel coupling between the outer p-type GaAsSb shell and the n-type InAs core in catalyst-free InAs/lnP/GaAsSb core-dualshell nanowires.We present a device fabrication protocol based on wet-etching processes on selected areas of the nanostructures that enables multiple configurations of measurements in the same nanowire-based device(i.e.shell-shell,core-core and core-shell).Low-temperature(4.2 K)transport in the shell-shell configuration in nanowires with 5 nm-thick InP barrier reveals a weak negative differential resistance.Differently,when the InP barrier thickness is increased to 10 nm,this negative differential resistance is fully quenched.The electrical resistance between the InAs core and the GaAsSb shell,measured in core-shell configuration,is significantly higher with respect to the resistance of the InAs core and of the GaAsSb shell.The field effect,applied via a back-gate,has an opposite impact on the electrical transport in the core and in the shell portions.Our results show that electron and hole free carriers populate the InAs and GaAsSb regions respectively and indicate InAs/InP/GaAsSb core-dualshell nanowires as an ideal system for the investigation of the physics of interacting electrons and holes at the nanoscale.
文摘A standard assumption when modelling linked sample data is that the stochastic properties of the linking process and process underpinning the population values of the response variable are independent of one another.This is often referred to as non-informative linkage.But what if linkage errors are informative?In this paper,we provide results from two simulation experiments that explore two potential informative linking scenarios.The first is where the choice of sample record to link is dependent on the response;and the second is where the probability of correct linkage is dependent on the response.We focus on the important and widely applicable problem of estimation of domain means given linked data,and provide empirical evidence that while standard domain estimation methods can be substantially biased in the presence of informative linkage errors,an alternative estimation method,based on a Gaussian approximation to a maximum likelihood estimator that allows for non-informative linkage error,performs well.
文摘Femoral glands of male lizards produce waxy secretions that are involved in inter- and intraspecific chemical communication. The main components of these secretions are proteins and lipids, the latter having been extensively studied and already associated to male quality. On the opposite, the composition and role of proteins are nearly unknown, the only available information coming from few studies on iguanids. These studies got the conclusion that proteins might have a communicative function, notably they could signal individual identity. A generalization of these findings requires the extension of protein analysis to other lizard families, and the primary detection of some patterns of individual variability. Using the common wall lizard Podarcis muralis as a model species, the protein fraction of the femoral pore secretions was investigated to provide the first characterization of this component in a lacertid lizard and to explore its source of variability, as a first step to support the hypothesized communicative role. Samples of proteins from femoral secretions were collected from 6 Italian populations and subjected to 1-dimensional electrophoresis. The binary vector of the band presence/absence was used to define the individual profiles. Protein fraction is found to have a structured pattern, with both an individual and a population component. Although the former supports the potential communicative role of proteins, the latter offers a double interpretation, phylogenetic or environmental, even though the phylogenetic effect seems more likely given the climatic resemblance of the considered sites. Further studies are necessary to shed light on both these issues.
基金funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 811226.
文摘Magnesium(Mg)implants have shown to cause image artefacts or distortions in magnetic resonance imaging(MRI).Yet,there is a lack of information on how the degradation of Mg-based implants influences the image quality of MRI examinations.In this study,Mg-based implants are analysed in vitro,ex vivo,and in the clinical setting for various magnetic field strengths with the aim to quantify metallic artefact behaviour.In vitro corroded Mg-based screws and a titanium(Ti)equivalent were imaged according to the ASTM F2119.Mg-based and Ti pins were also implanted into rat femurs for different time points and scanned to provide insights on the influence of soft and hard tissue on metallic artefact.Additionally,MRI data of patients with scaphoid fractures treated with CE-approved Mg-based compression screws(MAGNEZIX®)were analysed at various time points post-surgery.The artefact production of the Mg-based material decreased as implant material degraded in all settings.The worst-case imaging scenario was determined to be when the imaging plane was selected to be perpendicular to the implant axis.Moreover,the Mg-based implant outperformed the Ti equivalent in all experiments by producing lower metallic artefact(p<0.05).This investigation demonstrates that Mg-based implants generate significantly lower metallic distortion in MRI when compared to Ti.Our positive findings suggest and support further research into the application of Mg-based implants including post-operative care facilitated by MRI monitoring of degradation kinetics and bone/tissue healing processes.
文摘In order to reveal the nature of dark matter,it is crucial to detect its non-gravitational interactions with the standard model particles.The traditional dark matter searches focused on the so-called weakly interacting massive particles.However,this paradigm is strongly constrained by the null results of current experiments with high precision.Therefore there is a renewed interest of searches for heavy dark matter particles above TeV scale.The Large High Altitude Air Shower Observatory(LHAASO)with large effective area and strong background rejection power is very suitable to investigate the gamma-ray signals induced by dark matter annihilation or decay above TeV scale.In this document,we review the theoretical motivations and background of heavy dark matter.We review the prospects of searching for the gamma-ray signals resulted from dark matter in the dwarf spheroidal satellites and Galactic halo for LHAASO,and present the projected sensitivities.We also review the prospects of searching for the axion-like particles,which are a kind of well motivated light pseudo-scalars,through the LHAASO measurement of the very high energy gamma-ray spectra of astrophysical sources.
基金Supported by CERN and national agencies:CAPES,CNPq,FAPERJ and FINEP(Brazil)NSFC(China)+17 种基金CNRS/IN2P3(France)BMBF,DFG,HGF and MPG(Germany)INFN(Italy)FOM and NWO(The Netherlands)MNi SW and NCN(Poland)MEN/IFA(Romania)Min ES and FANO(Russia)Min ECo(Spain)SNSF and SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)NSF(USA)supported by IN2P3(France),KIT and BMBF(Germany),INFN(Italy),NWOSURF(The Netherlands),PIC(Spain),Grid PP(United Kingdom)support from EPLANET,Marie Sk lodowska-Curie ActionsERC(European Union),Conseil général de Haute-Savoie,Labex ENIGMASS and OCEVU,RégionAuvergne(France),RFBR(Russia),Xunta GalGENCAT(Spain),Royal Society and Royal Commission for the Exhibition of 1851(United Kingdom)
文摘The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse momentum, PT, and rapidity, y. The kinematic region of the measurements is pT〈20 GeV/c and 2.0 〈g〈4.5.The measurements use a data sample corresponding to an integrated luminosity of 3fb-1 collected by the LHCb detector in pp collisions at centre-of-mass energies √s=7 TeV in 2011 and √s=8 TeV in 2012. Based on previous LHCb results of the fragmentation fraction ratio,f∧0/b/fd,the branching fraction of the decay ∧0/b→ J/ψ pK-is measured to be B（∧0/b→ J/ψ pK-）=（3.17±0.04±0.07±0.34＋0.45/-0.28）×10-4,where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay -B/0 →J/ψ-K＊（892）0,and the fourth is due to the knowledge of f∧0/b/fd.The sum of the asymmetries in the production and decay between ∧0/b and ∧0/bis also measured as a function of PT and y.The previously published branching fraction of ∧0/b→ J/ψ pπ-,relative to that of ∧0/b→ J/ψ pK-,is updated. The branching fractions of ∧0/b→P＋c（→ J/ψp）K-are determined.
基金support from CERN and from the national agencies:CAPES,CNPq，FAPERJ and FINEP(Brazil)MOST and NSFC(China)+11 种基金CNRS/IN2P3(France)BMBF,DFG and MPG(Germany)INFN(Italy)KWO(Netherlands)MNiSW and NCN(Poland)MEN/IFA(Romania)MinES and FASO(Russia)MinECo(Spain)SNSF and SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)NSF(USA).
文摘A search for the doubly charmed baryon ■^+cc is performed through its decay to theΛ^+c K^-π^+ final state,using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7,8 and 13 TeV.The data correspond to a total integrated luminosity of 9 fb^-1.No significant signal is observed in the mass range from 3.4 to 3.8 GeV/c^2.Upper limits are set at 95%credibility level on the ratio of the ■^+cc production cross-section times the branching fraction to that ofΛ^+c and ■^++cc baryons.The limits are determined as functions of the ■^+cc mass for different lifetime hypotheses,in the rapidity range from 2.0 to 4.5 and the transverse momentum range from 4 to 15 GeV/c.
基金support from AvH Foundation(Germany)EPLANET,Marie Sk lodowska-Curie Actions and ERC(European Union)+11 种基金A*MIDEXANRLabex P2IOOCEVURégion Auvergne-Rh?ne-Alpes(France)Key Research Program of Frontier Sciences of CASCAS PIFIThousand Talents ProgramSci.&Tech.Program of Guangzhou(China)RFBR,RSF and Yandex LLC(Russia)GVA,Xunta Gal and GENCAT(Spain)the Royal Society and the Leverhulme Trust(United Kingdom)。
文摘A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No significant signal of the decay is observed and an upper limitof 1.1x 10^(-7)at 90%confidence level is set on the branching fraction.
基金CAPES,CNPq,FAPERJ and FINEP(Brazil)MOST and NSFC(China)+18 种基金CNRS/IN2P3(France)BMBF,DFG,MPG(Germany)INFN(Italy)NWO(Netherlands)MNiSW,NCN(Poland)MEN/IFA(Romania)MSHE(Russia)MICINN(Spain)SNSF,SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)DOE NP,NSF(USA).We acknowledge the computing resources that are provided by CERN,IN2P3(France),KIT and DESY(Germany),INFN(Italy),SURF(Netherlands),PIC(Spain),GridPP(United Kingdom),RRCKI and Yandex LLC(Russia),CSCS(Switzerland),IFIN-HH(Romania),CBPF(Brazil),PL-GRID(Poland)and NERSC(USA)AvH Foundation(Germany)EPLANET,Marie Sklodowska-Curie Actions and ERC(European Union)A*MIDEX,ANR,Labex P2IO and OCEVU,Region Auvergne-Rhdne-Alpes(France)Key Research Program of Frontier Sciences of CAS,CAS PIFI,CAS CCEPP,Fundamental Research Funds for the Central Universities,and Sci.Tech.Program of Guangzhou(China)RFBR,RSF and Yandex LLC(Russia)GVA,XuntaGal,GENCAT(Spain)the Leverhulme Trust,the Royal Society and UKRI(United Kingdom)。
文摘The first search for the doubly heavyΩ^(0)_(bc)baryon and a search for the E^(0)_(bc)baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 TeV,corresponding to an integrated luminosity of 5.2 fb^(-1).The baryons are reconstructed via their decays to Λ^(+)_(c)π^(-)and E^(+)_(c)π^(-).No significant excess is fbund for invariant masses between 6700 and 7300 MeV/c^(2),in a rapidity range from 2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/c.Upper limits are set on the ratio of the Ω^(0)_(bc)and E^(0)_(bc)production cross-section times the branching fraction to Λ^(+)_(c)π^(-)(E^(+)_(c)π^(-))relative to that of the Λ^(0)_(b)(E^(0)_(b))baryon,for different lifetime hypotheses,at 95%confidence level.The upper limits range from 0.5 x 10^(-4)to 2.5 x 10^(-4)for theΩ^(0)_(bc)→Λ^(+)_(c)π^(-)(E^(0)_(bc)→Λ^(+)_(c)π^(-))decay,and from 1.4x 10^(-3)to 6.9 x 10^(-3)for theΩ^(0)_(bc)→E^(+)_(c)π^(-)(E^(0)_(bc)→E^(+)_(c)π^(-))decay,depending on the considered mass and lifetime of theΩ^(0)_(bc)(E^(0)_(bc))baryon.
