Huntington’s(HD)and Parkinson’s diseases(PD)are neurodegenerative disorders caused by the death of GABAergic and dopaminergic neurons in the basal ganglia leading to hyperkinetic and hypokinetic symptoms,respectivel...Huntington’s(HD)and Parkinson’s diseases(PD)are neurodegenerative disorders caused by the death of GABAergic and dopaminergic neurons in the basal ganglia leading to hyperkinetic and hypokinetic symptoms,respectively.We review here the participation of purinergic receptors through intracellular Ca^2+signaling in these neurodegenerative diseases.The adenosine A2A receptor stimulates striatopallidal GABAergic neurons,resulting in inhibitory actions on GABAergic neurons of the globus pallidus.A2A and dopamine D2 receptors form functional heteromeric complexes inducing allosteric inhibition,and A2A receptor activation results in motor inhibition.Furthermore,the A2A receptor physically and functionally interacts with glutamate receptors,mainly with the mGlu5 receptor subtype.This interaction facilitates glutamate release,resulting in NMDA glutamate receptor activation and an increase of Ca2+influx.P2X7 receptor activation also promotes glutamate release and neuronal damage.Thus,modulation of purinergic receptor activity,such as A2A and P2X7 receptors,and subsequent aberrant Ca^2+signaling,might present interesting therapeutic potential for HD and PD.展开更多
The war on cancer was declared 40 years ago. While the potential for reducing deaths is increasing, so are the costs. Finding the right prioritization in our complex world is difficult;we present some interesting fact...The war on cancer was declared 40 years ago. While the potential for reducing deaths is increasing, so are the costs. Finding the right prioritization in our complex world is difficult;we present some interesting facts regarding other wars and aspects of society that are worth reflecting on as we struggle to find the right balance.展开更多
Purinergic receptors are among the first cell surface receptors expressed during embryonic development （Burnstock and Ulrich, 2011）. These are characterized based on their pharmacological properties of being activat...Purinergic receptors are among the first cell surface receptors expressed during embryonic development （Burnstock and Ulrich, 2011）. These are characterized based on their pharmacological properties of being activated by adenosine or purine/pyrimidine nucleotides as P1 and P2 receptors. P2 receptors are further classified by their structure as P2Y metabotropic and P2X ionotropic receptors.展开更多
Neural stem/progenitor cells：Radial glial cells constitute multipotent cells in the ventricular zone,lining the wall of the lateral ventricle of the embryonic brain.They have the capacity to give rise to cells belong...Neural stem/progenitor cells：Radial glial cells constitute multipotent cells in the ventricular zone,lining the wall of the lateral ventricle of the embryonic brain.They have the capacity to give rise to cells belonging to all three major linages（neurons,astrocytes and oligodendrocytes）of the nervous system（Tang and Illes,2017）.展开更多
We report the extraordinarily large positive magnetoresistances （MR, 69400% at 4.5K under a magnetic field of 8.15 T）, de Hass-van Alphen oscillations effect at 10 K and the semimetal-Jnsulator-like transition in a ...We report the extraordinarily large positive magnetoresistances （MR, 69400% at 4.5K under a magnetic field of 8.15 T）, de Hass-van Alphen oscillations effect at 10 K and the semimetal-Jnsulator-like transition in a wide range of temperature in highly oriented pyrolitic graphite （HOPG）. Besides a dominating ordinary MR （OMR） mechanism in the free-electron mode, it is realized from qualitative analysis that the Coulomb interacting quasiparticles within graphite layers play some roles. However it is difficult to associate the transition with the simple OMR theory. In order to investigate the possible origins of the transition, further analysis is carried out. It is revealed that the magnetic-field-induced behaviour is responsible for the semimetal-insulator-like transitions in HOPG.展开更多
Recently,a paper published in Science reported discovery of sensory peripheral glial cells[1].This paper demonstrated a rather unexpected property of non-myelinating Schwann cells(also known as Remak cells)dwelling in...Recently,a paper published in Science reported discovery of sensory peripheral glial cells[1].This paper demonstrated a rather unexpected property of non-myelinating Schwann cells(also known as Remak cells)dwelling in the subepidermal border of the skin[2].These glial cells and their interactions with nociceptive nerve terminals were characterized using a variety of genetic labelling tools,transmission electron microscopy,immunocytochemistry.展开更多
In this paper,a non-thermal atmospheric pressure plasma jet at high streaming velocity operating with ambient air is highlighted.In the present technological approach,the employment of air poses a significant challeng...In this paper,a non-thermal atmospheric pressure plasma jet at high streaming velocity operating with ambient air is highlighted.In the present technological approach,the employment of air poses a significant challenge.The high oxygen concentration in air results in a reduced concentration of reactive species in combination with a short species lifetime.The plasma jet assembly presented here contains a special dielectric barrier with a high secondary emission coefficient.In this way,the electron density and in turn the density of reactive species is increased.In addition,the plasma jet assembly is equipped with a short electrode.This leads to a higher voltage across the discharge gap and in turn to an increased density of reactive plasma species.The plasma jet is formed within and emitted by a small conical nozzle.A high-speed gas flow with gas velocity of 340 m/s was achieved at the end of the nozzle.In the jet the concentration of toxic and unwanted neutral plasma species like O3 or NOx is significantly reduced because of the shorter residence time within the plasma.The range of short-lived active plasma species is in turn considerably enhanced.The jet efficiency and action range measured through the oxidation of a test surface were determined by measuring the increase of surface tension of a polypropylene substrate via contact angle measurements after plasma treatment.Numerical modeling of the plasma plume indicates that oxygen atoms are in fact the main active species in the plasma plume.展开更多
Overlapping latent fingermarks constitute a serious challenge to database related recognition and matching algorithms in biometry, forensic and crime scene investigations. Mass spectrometry imaging (MSI) is a powerful...Overlapping latent fingermarks constitute a serious challenge to database related recognition and matching algorithms in biometry, forensic and crime scene investigations. Mass spectrometry imaging (MSI) is a powerful tool for deciphering and analyzing overlapping fingermarks based on the individual chemical information of each deposit. Fingermark MSI in practice still requires a subjective judgment of an MSI expert, such that rapid analysis, automation, standardization, and a quantitative evaluation of the complete detection and separation process of overlapped fingermarks from MSI data sets is the ultimate goal and will be necessary to become an accepted process in criminal investigations and law enforcement. Here we investigated the feasibility and efficiency of different statistical approaches for the separation of overlapped latent fingermarks based on MSI data. Entropy analysis of generated m/z-images was used to evaluate the results obtained from the statistical analysis. Furthermore, we demonstrate and discuss the opportunity to reconstitute and separate overlapping fingermarks by discrete scanning at selected x,y-positions defined from a previous image analysis using a more simple schema based on visible and therefore optical distinguishable overlapped ink-based fingermarks. The overlapped latent fingermarks were developed by rapid gold sputter coating and analyzed by laser based MSI, without (organic) matrix preparation. Latent finger marks can be transferred from the substrate/surface with and conserved on a soft gold sputtered soft membrane at low temperatures.展开更多
We recorded continuous seismic noise close and around two wind parks with different geological site conditions in order to investigate the effects of wind turbines on seismic signals in the frequency interval between ...We recorded continuous seismic noise close and around two wind parks with different geological site conditions in order to investigate the effects of wind turbines on seismic signals in the frequency interval between 1 and 10 Hz. In wind park Fraureuth-Beiersdorf (5 turbines, 11 km south from Zwickau, Saxony), we used small seismic networks, with 3 to 5 stations for 1 - 2 weeks. In Heinde (2 turbines, close to Hildesheim, Lower Saxony), we recorded 1 week with one station around 1 km away from the wind turbines and some additional stations for several hours only. With the spectrogram analysis of the data, we clearly identify the diurnal variation on the spectral amplitude separately from the noise generated by the turbines. The turbine noise appears at certain frequency bands around 2.2, 2.7, 3.3, 4.5, 5.2 and 6.6 Hz. A linear relation between the spectral amplitudes of these frequency bands and the wind velocity or rotation velocity of the turbines is clearly identified. The seismic signals produced by the operation of the wind turbines are not peaks at single frequencies, but look more like frequency bands with increased noise amplitudes. They could be identified up to at least 10 km in the case of Fraureuth-Beiersdorf. These bands depend on numerous parameters, i.e. wind turbine height, weight and construction, number of turbines, geology, etc. In both wind parks we also recorded along profiles with increasing distances from the wind turbines. With the analysis of these data, we propose an amplitude attenuation model for the wind park Fraureuth-Beiersdorf to a distance of 9 km, and for Heinde to a distance of 4 km. The attenuation models for both wind parks are quite different, depending probably on the local geology and topography.展开更多
Ni/SiO2-ZrO2 catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N2 sorption, temperature programmed oxidation, temperature programmed reduc- tion, and tes...Ni/SiO2-ZrO2 catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N2 sorption, temperature programmed oxidation, temperature programmed reduc- tion, and tested for their activity and stability in the dry reforming of methane with carbon dioxide at 850 ℃, gas hourly space velocity of 6000 and 1800 h^-1 and atmo- spheric pressure. The SiO2-ZrO2 support as obtained through a simple and efficient sol-gel synthesis is highly porous （ABET = 90 m^·g^-1, dp= 4.4 nm） with a homogeneously distributed Si-content of 3 wt-%. No loss of Si or formation ofmonoclinic ZrO2, even after steaming at 850 ℃ for 160 h, was detectable. The catalyst with 5 wt-% Ni loading in its fully reduced state is stable over 15 h on-stream in the dry reforming reaction. If the catalyst was not fully reduced, a reduction during the early stages of dry reforming is accompanied by the deposition of up to 44 mg· g^-1 carbon as shown by experiments in a magnetic suspension balance. Rapid coking occurs for increased residence times and times-on-stream starting at 50 h. The Ni loading of 5 wt-% on SiO2-ZrO2 was shown to provide an optimal balance between activity and coking tendency.展开更多
A numerical scheme for the Reissner-Mindlin plate model is proposed.The method is based on a discrete Helmholtz decomposition and can be viewed as a generalization of the nonconforming finite element scheme of Arnold ...A numerical scheme for the Reissner-Mindlin plate model is proposed.The method is based on a discrete Helmholtz decomposition and can be viewed as a generalization of the nonconforming finite element scheme of Arnold and Falk[SIAM J.Numer.Anal.,26(6):1276-1290,1989].The two unknowns in the discrete formulation are the in-plane rotations and the gradient of the vertical displacement.The decomposition of the discrete shear variable leads to equivalence with the usual Stokes system with penalty term plus two Poisson equations and the proposed method is equivalent to a stabilized discretization of the Stokes system that generalizes the Mini element.The method is proved to satisfy a best-approximation result which is robust with respect to the thickness parameter t.展开更多
基金the Sao Paulo Research Foundation(FAPESP,2018/07366-4)a Fellowship from the National Council for Scientific and Technological Development(CNPq,306392/2017-8)+5 种基金postdoctoral fellowships from FAPESP(2015/13345-1,2019/268520,and 2018/17504-5)a doctoral fellowship from FAPESP(2019/24553-5)a master fellowship from CNPq(133396/2019-3)the fellowship from National Key R&D Program of China(2019YFC1709101)The Project First-Class Disciplines Development(CZYHW1901)of Chengdu University of TCM and Sichuan Science and Technology Program(2019YFH0108,2018SZ0257)supported by Russian Science Foundation grant 20-14-00241。
文摘Huntington’s(HD)and Parkinson’s diseases(PD)are neurodegenerative disorders caused by the death of GABAergic and dopaminergic neurons in the basal ganglia leading to hyperkinetic and hypokinetic symptoms,respectively.We review here the participation of purinergic receptors through intracellular Ca^2+signaling in these neurodegenerative diseases.The adenosine A2A receptor stimulates striatopallidal GABAergic neurons,resulting in inhibitory actions on GABAergic neurons of the globus pallidus.A2A and dopamine D2 receptors form functional heteromeric complexes inducing allosteric inhibition,and A2A receptor activation results in motor inhibition.Furthermore,the A2A receptor physically and functionally interacts with glutamate receptors,mainly with the mGlu5 receptor subtype.This interaction facilitates glutamate release,resulting in NMDA glutamate receptor activation and an increase of Ca2+influx.P2X7 receptor activation also promotes glutamate release and neuronal damage.Thus,modulation of purinergic receptor activity,such as A2A and P2X7 receptors,and subsequent aberrant Ca^2+signaling,might present interesting therapeutic potential for HD and PD.
文摘The war on cancer was declared 40 years ago. While the potential for reducing deaths is increasing, so are the costs. Finding the right prioritization in our complex world is difficult;we present some interesting facts regarding other wars and aspects of society that are worth reflecting on as we struggle to find the right balance.
基金support from Fundacao de Amparo à Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)+2 种基金the Provost’s Office for Research of the University of Sao Paulo, Grant number: 2011.1.9333.1.3 (NAPNA-USP)support from the German Research Council (IL 20/182, RI 2092/1-2, IL 20/21-1)the Sino-German Centre for the Support of Science (GZ 919)
文摘Purinergic receptors are among the first cell surface receptors expressed during embryonic development （Burnstock and Ulrich, 2011）. These are characterized based on their pharmacological properties of being activated by adenosine or purine/pyrimidine nucleotides as P1 and P2 receptors. P2 receptors are further classified by their structure as P2Y metabotropic and P2X ionotropic receptors.
基金supported by Deutsche Forschungsgemeinschaft(DFGIL 20/21-1)Sino-German Centre(GZ919)
文摘Neural stem/progenitor cells：Radial glial cells constitute multipotent cells in the ventricular zone,lining the wall of the lateral ventricle of the embryonic brain.They have the capacity to give rise to cells belonging to all three major linages（neurons,astrocytes and oligodendrocytes）of the nervous system（Tang and Illes,2017）.
文摘We report the extraordinarily large positive magnetoresistances （MR, 69400% at 4.5K under a magnetic field of 8.15 T）, de Hass-van Alphen oscillations effect at 10 K and the semimetal-Jnsulator-like transition in a wide range of temperature in highly oriented pyrolitic graphite （HOPG）. Besides a dominating ordinary MR （OMR） mechanism in the free-electron mode, it is realized from qualitative analysis that the Coulomb interacting quasiparticles within graphite layers play some roles. However it is difficult to associate the transition with the simple OMR theory. In order to investigate the possible origins of the transition, further analysis is carried out. It is revealed that the magnetic-field-induced behaviour is responsible for the semimetal-insulator-like transitions in HOPG.
基金supported by National Key R&D Program of China(2019YFC1709101)the Project First-Class Disciplines Development of Chengdu University of Traditional Chinese Medicine(CZYHW1901)+1 种基金the National Natural Science Foundation of China(81774437 and 81973969)Science and Technology Program of Sichuan Province,China(2019YFH0108 and 2018SZ0257)。
文摘Recently,a paper published in Science reported discovery of sensory peripheral glial cells[1].This paper demonstrated a rather unexpected property of non-myelinating Schwann cells(also known as Remak cells)dwelling in the subepidermal border of the skin[2].These glial cells and their interactions with nociceptive nerve terminals were characterized using a variety of genetic labelling tools,transmission electron microscopy,immunocytochemistry.
文摘In this paper,a non-thermal atmospheric pressure plasma jet at high streaming velocity operating with ambient air is highlighted.In the present technological approach,the employment of air poses a significant challenge.The high oxygen concentration in air results in a reduced concentration of reactive species in combination with a short species lifetime.The plasma jet assembly presented here contains a special dielectric barrier with a high secondary emission coefficient.In this way,the electron density and in turn the density of reactive species is increased.In addition,the plasma jet assembly is equipped with a short electrode.This leads to a higher voltage across the discharge gap and in turn to an increased density of reactive plasma species.The plasma jet is formed within and emitted by a small conical nozzle.A high-speed gas flow with gas velocity of 340 m/s was achieved at the end of the nozzle.In the jet the concentration of toxic and unwanted neutral plasma species like O3 or NOx is significantly reduced because of the shorter residence time within the plasma.The range of short-lived active plasma species is in turn considerably enhanced.The jet efficiency and action range measured through the oxidation of a test surface were determined by measuring the increase of surface tension of a polypropylene substrate via contact angle measurements after plasma treatment.Numerical modeling of the plasma plume indicates that oxygen atoms are in fact the main active species in the plasma plume.
文摘Overlapping latent fingermarks constitute a serious challenge to database related recognition and matching algorithms in biometry, forensic and crime scene investigations. Mass spectrometry imaging (MSI) is a powerful tool for deciphering and analyzing overlapping fingermarks based on the individual chemical information of each deposit. Fingermark MSI in practice still requires a subjective judgment of an MSI expert, such that rapid analysis, automation, standardization, and a quantitative evaluation of the complete detection and separation process of overlapped fingermarks from MSI data sets is the ultimate goal and will be necessary to become an accepted process in criminal investigations and law enforcement. Here we investigated the feasibility and efficiency of different statistical approaches for the separation of overlapped latent fingermarks based on MSI data. Entropy analysis of generated m/z-images was used to evaluate the results obtained from the statistical analysis. Furthermore, we demonstrate and discuss the opportunity to reconstitute and separate overlapping fingermarks by discrete scanning at selected x,y-positions defined from a previous image analysis using a more simple schema based on visible and therefore optical distinguishable overlapped ink-based fingermarks. The overlapped latent fingermarks were developed by rapid gold sputter coating and analyzed by laser based MSI, without (organic) matrix preparation. Latent finger marks can be transferred from the substrate/surface with and conserved on a soft gold sputtered soft membrane at low temperatures.
文摘We recorded continuous seismic noise close and around two wind parks with different geological site conditions in order to investigate the effects of wind turbines on seismic signals in the frequency interval between 1 and 10 Hz. In wind park Fraureuth-Beiersdorf (5 turbines, 11 km south from Zwickau, Saxony), we used small seismic networks, with 3 to 5 stations for 1 - 2 weeks. In Heinde (2 turbines, close to Hildesheim, Lower Saxony), we recorded 1 week with one station around 1 km away from the wind turbines and some additional stations for several hours only. With the spectrogram analysis of the data, we clearly identify the diurnal variation on the spectral amplitude separately from the noise generated by the turbines. The turbine noise appears at certain frequency bands around 2.2, 2.7, 3.3, 4.5, 5.2 and 6.6 Hz. A linear relation between the spectral amplitudes of these frequency bands and the wind velocity or rotation velocity of the turbines is clearly identified. The seismic signals produced by the operation of the wind turbines are not peaks at single frequencies, but look more like frequency bands with increased noise amplitudes. They could be identified up to at least 10 km in the case of Fraureuth-Beiersdorf. These bands depend on numerous parameters, i.e. wind turbine height, weight and construction, number of turbines, geology, etc. In both wind parks we also recorded along profiles with increasing distances from the wind turbines. With the analysis of these data, we propose an amplitude attenuation model for the wind park Fraureuth-Beiersdorf to a distance of 9 km, and for Heinde to a distance of 4 km. The attenuation models for both wind parks are quite different, depending probably on the local geology and topography.
文摘Ni/SiO2-ZrO2 catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N2 sorption, temperature programmed oxidation, temperature programmed reduc- tion, and tested for their activity and stability in the dry reforming of methane with carbon dioxide at 850 ℃, gas hourly space velocity of 6000 and 1800 h^-1 and atmo- spheric pressure. The SiO2-ZrO2 support as obtained through a simple and efficient sol-gel synthesis is highly porous （ABET = 90 m^·g^-1, dp= 4.4 nm） with a homogeneously distributed Si-content of 3 wt-%. No loss of Si or formation ofmonoclinic ZrO2, even after steaming at 850 ℃ for 160 h, was detectable. The catalyst with 5 wt-% Ni loading in its fully reduced state is stable over 15 h on-stream in the dry reforming reaction. If the catalyst was not fully reduced, a reduction during the early stages of dry reforming is accompanied by the deposition of up to 44 mg· g^-1 carbon as shown by experiments in a magnetic suspension balance. Rapid coking occurs for increased residence times and times-on-stream starting at 50 h. The Ni loading of 5 wt-% on SiO2-ZrO2 was shown to provide an optimal balance between activity and coking tendency.
文摘A numerical scheme for the Reissner-Mindlin plate model is proposed.The method is based on a discrete Helmholtz decomposition and can be viewed as a generalization of the nonconforming finite element scheme of Arnold and Falk[SIAM J.Numer.Anal.,26(6):1276-1290,1989].The two unknowns in the discrete formulation are the in-plane rotations and the gradient of the vertical displacement.The decomposition of the discrete shear variable leads to equivalence with the usual Stokes system with penalty term plus two Poisson equations and the proposed method is equivalent to a stabilized discretization of the Stokes system that generalizes the Mini element.The method is proved to satisfy a best-approximation result which is robust with respect to the thickness parameter t.
