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Study of capillary transit time distribution in coherent hemodynamics spectroscopy

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Journal of Innovative Optical Health Sciences 2015年第2期8卷 78-86页

作者： Angelo Sassaroli jana Kainerstorfer Sergio Fantini Department of Biomedical Engineering Tufts University 4 Colby StreetMedfordMA 02155USA

A recently proposed analytical hemodynamie modell[***,Neurolmage 85,202-221(2014)]is able to predict the changes of oxy,deoxy,and total hemoglobin concentrations(model outputs)given arbitrary changes in blood flow,blood volume,and rate of oygen consumption(model inputs).One asumption of this model is that the capillary compartment is characterized by a single blood transit *** this work,we have extended the original model by considering a distribution of capillary transit times and we have compared the outputs of both models(original and extended)for the case of sinusoidal input signals at different frequencies,which realizes the new technique of coherent hemodynamics spectroscopy(CHS).For the calculations with the original model,we have used the mean value of the distribution of capillary transit times con-sidered in the extended *** have found that,for distributions of capillary transit times having mean values around 1 s and a standard deviation less than about 45%of the mean value,the original and extended models yield the same CHS spectra(i.e.,model outputs versus fre-quency of ocillation)within typical experimental *** wider capillary transit time dis-tributions,the two models yield different CHS *** assuming that Poiseuille's law is valid in the capillary compartment,we have related the distribution of capillary transit times to the distributions of capillary lengths and capillary speed of blood flow to calculate the average capillary and venous *** have found that,for standard deviations of the capillanry transit time distrilbution that are less than about 80%of the mean value,the average capillary saturation is always larger than the venous *** contrast,the average capillary satu-ration may be less than the venous saturation for wider distributions of the capillary transit times.

关键词： Coherent hemodynamics spectroscopy hermodynamie model near-infrared spectros-copy capillary transit time hemoglobin saturation

Impact of alpha-synuclein pathology on adult neurogenesis: evidence for multilayered mechanisms

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Neural Regeneration Research 2022年第7期17卷 1491-1492页

作者： jana Bonsberger Franziska Richter Milos Stanojlovic Department of Pharmacology Toxicology and PharmacyUniversity of Veterinary MedicineHannoverGermany

Parkinson’s disease(PD)is the second most common neurodegenerative disease affecting 8–10 million people ***,PD is the fastest-growing neurodegenerative disease and it is predicted that the number of patients will double in the next thirty ***,PD is characterized by the presence of protein aggregations called Lewy bodies(LB)and by degeneration of dopaminergic neurons in the substantia nigra pars compacta.

关键词： degeneration pathology Impact

Promoting neuronal regeneration using extracellular vesicles loaded with superparamagnetic iron oxide nanoparticles

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Neural Regeneration Research 2016年第1期11卷 61-63页

作者： Jenni Neubert jana Glumm Institute of Cell Biology and Neurobiology Center for AnatomyCharité-Universit?tsmedizin Berlin Department of Neurosurgery HELIOS Klinikum Berlin Buch

Intercellular communication between neurons and glial cells via extracellular vesicles（EVs）as a novel mechanism of information transfer has been shown to be involved in regeneration processes within the central nervous system（CNS）（Rajendran et al.,2014）.Hence,to take advantage of EV signaling for therapeutic applications appears to be a completely new approach to promote regeneration.

关键词： vesicles regeneration neuronal loaded glial instance targeting synaptic exosome hippocampal

Propriospinal interneurons in the spotlight for anatomical and functional recovery after spinal cord injury

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Neural Regeneration Research 2015年第11期10卷 1737-1738页

作者： Martin Pohland jana Glumm Institute of Cell Biology and Neurobiology Center for Anatomy Charite-Universitatsmedizin Berlin Department of Neurosurgery HELIOS Klinikum Berlin Buch

Spinal cord injury（SCI）with consecutive paralysis below the lesion level is a severe disorder affecting the patient for the rest of his or her *** far,there is no known fundamental intervention strategy for efficiently helping those patients regain their motor abilities,despite intense research in this ***,effective treatment for those patients is still an open question. A spinal cord injury is accompanied by a prima- ry, severe and irreversible neuronal cell death in the trauma region, fol- lowed by a secondary extensive cell necrosis in the lesion surrounding areas. Nevertheless, recent studies indicate that regeneration after spinal cord injury could be possible if three substantial steps are fulfilled：（1） reduction of the inhibitory environment at the SCI lesion site, （2） iden- tification of a neural substrate to establish new spinal circuits, and （3） support of these circuits to form permanent, functional motor, sensory, or autonomic connections （Dru and Hoh, 2015）.

关键词： Propriospinal interneurons in the spotlight for anatomical and functional recovery after spinal cord injury EGFP GAD DCX

Fluorescence detection of Europiumdoped very small superparamagnetic iron oxide nanoparticles in murine hippocampal slice cultures

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Neural Regeneration Research 2018年第4期13卷 637-638页

作者： Martin Pohland Yuske Kobayashi jana Glumm Institute of Cell Biology and Neurobiology Center for Anatomy Charite -Universitaitsmedizin Berlin Berlin Germany Department of Interventional and Diagnostic Radiology and Nuclear Medicine Universitatsklinikum Hamburg-EppendorfHamburg Germany Department of neurosurgery HELIOS Klinikum Berlin BuchBerlin Germany

In the late 1980s,superparamagnetic iron oxide nanoparticles（SPIO）moved into focus as contrast agents in magnetic resonance imaging（MRI）,due to their strong relaxivity and resulting higher resolution of *** the time,no one anticipated their high potential in basic research or for medical diagnostic andtreatment. Since then, SPIO have been evaluated notonly as spe- cific markers for MRI, but also for cell labeling and tracking （Li et al., 2013）.

关键词： Eu Fluorescence detection of Europiumdoped very small superparamagnetic iron oxide nanoparticles in murine hippocampal slice cultures

Migration phenology determines niche use of East Asian buntings (Emberizidae)during stopover

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Current Zoology 2018年第6期64卷 681-692页

作者： Wieland HEIM jana A.ECCARD Franz BAIRLEIN Institute of Landscape Ecology Munster UniversityHeisenbergstraβe 2Munster48149Germany Animal Ecology Institute of Biology and BiochemistryUniversitat PotsdamMaulbeerallee 1Potsdam14469Germany Institute of Avian Research "Vogelwarte Helgoland" An der Vogelwarte 21Wilhelmshaven28386Germany

Stopover niche utilization of birds during migration has not gained much attention so far,since the majority of the studies focuses on breeding or wintering ***,stopover sites are crucial for migratory *** are often used by a multitude of species,which could lead to increased *** this work,we investigated niche use of 8 migratory and closely related Emberiza bunting species at a stopover site in Far East Russia,situated on the poorly studied East Asian *** used bird ringing data to evaluate morphological similarity as well as niche overlap on the trophic,spatial,and temporal *** morphology was used as a proxy for their trophic *** were able to prove that a majority of the species occupies well-defined stopover niches on at least one of the *** breadth and niche overlap differ between spring and autumn season with higher overlap found during *** differences are mostly related to overall size and wing *** temporal dimension is most important for segregation among the studied ***,all species seem to exhibit a rather strict and consistent phenological *** occurrence at the study site is highly correlated with their geographic origin and the length of their migration *** assume that buntings are able to use available resources opportunistically during stopover,while trying to follow a precise schedule in order to avoid competition and to ensure individual fitness.

关键词： bird migration Emberiza habitat use non-breeding phenology stopover

Effect of Sintering Temperature and Heating Rate on Crystallite Size,Densification Behaviour and Mechanical Properties of Al-MWCNT Nanocomposite Consolidated via Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2018年第10期31卷 1019-1030页

作者： Lavish Kumar Singh Alok Bhadauria Subhodeep jana Tapas Laha Department of Metallurgical and Materials Engineering Indian Institute of Technology Kharagpur Kharagpur India Centre for Healthcare Science and Technology Indian Institute of Engineering Science and Technology Shibpur India

Powder mixture of ball-milled aluminium and functionalized multi-walled carbon nanotubes was compacted via spark plasma sintering （SPS） to study effects of sintering temperature and heating rate. An increase in sintering temperature led to an increase in crystallite size and density, whereas an increase in heating rate exerted the opposite effect. The crystallite size and relative density increased by 85.0% and 14.3%, respectively, upon increasing the sintering temperature from 400 to 600℃, whereas increasing the heating rate from 25 to 100 ℃/min led to respective reduction by 30.0% of crystallite size and 1.8% of relative density. The total punch displacement during SPS for the nanocomposite sintered at 600 ℃ （1.96 mm） was much higher than that of the sample sintered at 400 ℃ （1.02 mm） confirming positive impact of high sintering temperature on densification behaviour. The maximum improvement in mechanical properties was exhibited by the nanocomposite sintered at 600 ℃ at a heating rate of 50℃/min displaying microhardness of 81 4- 3.6 VHN and elastic modulus of 89 4- 5.3 GPa. The nanocomposites consolidated at 400 ℃ and 100 ℃/min, in spite of having relatively smaller crystallite size, exhibited poor mechanical properties indicating the detrimental effect of porosity on the mechanical properties.

关键词： Al nanocomposite Multi-walled carbon nanotubes Ball milling Spark plasma sintering Densification behaviour Mechanical properties

Effect of storage conditions on long-term stability of Ag nanoparticles formed via green synthesis

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1177-1182页

作者： Oksana Velgosova Elena Cizmarova Jaroslav Málek jana Kavulicova Institute of Materials Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia Department of Materials Engineering Faculty of Mechanical Engineering Czech Technical University in Prague Karlovo nám. 13 121 32 Prague 2 Czech Republic Institute of Metallurgy Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia

Spherical Ag nanoparticles(AgNPs) with a diameter of 20 nm or smaller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term stability of AgNPs was investigated. UV/Vis spectrophotometry, transmission electron microscopy, and dynamic light scattering measurements revealed that the long-term stability of AgNPs was influenced by light and temperature conditions. The most significant loss of stability was observed for the AgNPs stored in daylight at room temperature. The AgNPs stored under these conditions began to lose their stability after approximately 30 d; after 100 d, a substantial amount of agglomerated particles settled to the bottom of the Erlenmeyer flask. The AgNPs stored in the dark at room temperature exhibited better long-term stability. Weak particle agglomeration began at approximately the 100 th day. The AgNPs stored in the dark at about 5℃ exhibited the best long-term stability; the AgNPs stored under such conditions remained spherical, with a narrow size distribution, and stable(no agglomeration) even after 6 months. Zeta-potential measurements confirmed better dispersity and stability of AgNPs stored under these conditions.

关键词： silver nanoparticles stability storage conditions green synthesis Parachlorella kessleri

Theoretical study of differential cross sections for the ionization of helium by fast proton impact

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Chinese Physics B 2024年第11期33卷 255-264页

作者： M Mondal B Mandal T Mistry D jana M Purkait Department of Physics Ramakrishna Mission Residential CollegeNarendrapurKolkata-700103India

We present the angular distribution of the ejected electron for single ionization of He by fast proton impact.A fourbody formalism of the three-Coulomb wave is applied to calculate the triple differential cross sections at several impact energies in the scattering,perpendicular and azimuthal ***,the three-body formalism of three-Coulomb,two-Coulomb and first Born approximation models has also been used to study the many-body effect on electron emission and the validity of the *** the three-Coulomb wave model,the final state wave function incorporates distortion due to the three-body mutual Coulombic *** this formalism,we use an uncorrelated and correlated Born initial state,which consists of a plane wave for the incoming projectile times a two-electron bound state wavefunction of the helium atom representing the 1s2(1S)***,in the case of the three-body formalism,the initial state wavefunction consists of a long-range Coulomb distortion for the incoming projectile and one active electron of the He atom described by the Roothaan–Hartree–Fock *** structure with a single or two peaks with unequal intensity is observed in the angular distributions of the triple differential cross sections for the different kinematic *** addition,the influence of static electron correlations is investigated using different bound state wavefunctions for the ground state of the He *** the four-body formalism,the present computations are very fast by reducing a nine-dimensional integral to a two-dimensional real *** the simplicity and speed of the proposed quadrature,the comparison shows that the obtained results are in reasonable agreement with the experiment and are compatible with those of other theories.

关键词： ionization cross sections collision atoms ions