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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

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

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

Interplay between strong Allee effect, harvesting and hydra effect of a single population discrete-time system

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International Journal of Biomathematics 2016年第1期9卷 65-89页

作者： Debaldev jana Elsayed m. Elsayed Ecological modelling LaboratoryDepartment of Zoology Visva-Bharati University Santiniketan 731235 India mathematics DepartmentFaculty of Science King Abdulaziz UniversityP. O. Box 80203 Jeddah 21589 Saudi Arabia Department of mathematicsFaculty of Science Mansoura University Mansoura 35516 Egypt

The dynamics of a single population with non-overlapping generations can be described deterministically by a scalar difference equation in this study. A discrete-time Beverton- Holt stock recruitment model with Allee effect, harvesting and hydra effect is proposed and studied. model with strong Allee effect results from incorporating mate limitation in the Beverton-Holt model. We show that these simple models exhibit some interesting （and sometimes unexpected） phenomena such as the hydra effect, sudden collapses and essential extinction. Along with this, harvesting is a socio-economie issue to continue any system generation after generation. Different dynamical behaviors for these situations have been illustrated numerically also. The biological implications of our analytical and numerical findings are discussed critically.

关键词： Beverton-Holt model hydra effect harvesting Allee effect.

Treatment of biliary tract cancer with NVP-AEW541:mechanisms of action and resistance

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World Journal of Gastroenterology 2010年第2期16卷 156-166页

作者： Samuel Wolf jana Lorenz Joachim mssner marcus Wiedmann Department of Internal medicineⅡ University of Leipzig Department of Internal medicineⅠ St. Mary's Hospital

AIm:To investigate in vitro treatment with NVPAEW541,a small molecule inhibitor of insulin-like growth factor-1 receptor(IGF-1R),in biliary tract cancer (BTC),since this disease is associated with a poor prognosis due to wide resistance to chemotherapeutic agents and ***:Cell growth inhibition by NVP-AEW541 was studied in vitro in 7 human BTC cell lines by automated cell *** addition,the anti-tumoral mechanism of NVP-AEW541 was studied by Western blotting,cell cycle analysis and reverse transcription-polymerase chain reaction(RT-PCR).Anti-tumoral drug effect in combination with gemcitabine,5-fluorouracil(5-FU)and Polo-like kinase 1 inhibitor BI2536 was also studied. RESULTS:In vitro treatment with NVP-AEW541 suppressed growth in all human BTC cell lines,however response was lower in gallbladder *** withNVP-AEW541 was associated with dephosphorylation of IGF-1R and *** contrast,phosphorylation of p42/p44 and Stat3 and expression of Bcl-xL were inconsistently *** addition,treated cells showed cell cycle arrest at the G1/S-checkpoint and an increase in sub-G1 ***,IGF-1R and its ligands IGF-1 and IGF-2 were co-expressed in RT-PCR,suggesting an autocrine loop of tumor cell *** with gemcitabine,NVP-AEW541 exerted synergistic effects, particularly at low concentrations,while effects of combination with 5-FU or BI 2536 were only additive. CONCLUSION:Our findings suggest that NVP-AEW541 is active against BTC in vitro and potentiates the efficacy of gemcitabine.

关键词： Tyrosine kinase inhibitor Cholangiocarcinoma Gemcitabine NVP-AEW541

Rilmenidine prevents blood pressure increase in rats with compromised nitric oxide production

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Acta Pharmacologica Sinica 2004年第12期25卷 74-80页

作者： mria GEROV,Jozef TRK,Ol’ga PECHV,jana mATUKOV Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute of Pathophysiology medical School Comenius University Bratislava Slovak Republic Now in Center for Blood Research and Department of Pathology Harvard medicalSchool Boston USA.

AIm: To search tools of high blood pressure in the model of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilmenidine, agonist of imidazoline receptors, which was suggested to modulate central sympathetic outflow. mETHODS: Three experimental groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine methyl ester (L-NAmE) 40 mg·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of imidazoline receptors rilmenidine 3 mg·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasmeasured weekly noninvasively. At the end of experiment aortic ring isometric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determined. RESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. Rilmenidine administered simultaneously with L-NAmE (group II) prevented the increase of blood pressure which did not differ significantly from control values; aortic ring relaxation to acetylcholine did not differ from control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: Rilmenidinehas aremarkable role inNO-defective hypertension, possibly by inhibiting central sympathetic outflow and by affecting receptors in vascular smooth muscle also. The prime cause of hypertension in this experimental model - the compromised production of NO due to inhibition of NOS - was not affected by rilmenidine.

关键词： NO deficiency hypertension imidazoline receptor nitric-oxide synthase sympathetic activity

Hydromagnetic flow between two porous disks rotating about non-coincident axes

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Acta mechanica Sinica 2008年第5期24卷 489-496页

作者： m.Guria B.K.Das R.N.jana C.Erdem Imrak Department of Applied mathematics Vidyasagar UniversityMidnapore 721 102West BengalIndia Department of mechanical Engineering Istanbul Technical UniversityGumussuyuIstanbul 34439Turkey

Hydromagnetic flow between two porous disks rotating with same angular velocity Ω about two noncoincident axes has been studied in the presence of a uniform transverse magnetic field. An exact solution of the governing equations has been obtained in a closed form. It is found that the primary velocity f/Ωl increases and the secondary velocity g/Ωl decreases with increase in either Reynolds number Re or the Hartman number m. It is also found that the torque at the disk η= 0 increases with increase in either m^2 or K^2. On the other hand there is no torque at the disk η= 1 for large m^2 and K^2. The heat transfer characteristic has also been studied on taking viscous and Joule dissipation into account. It is seen that the temperature increases with increase in either m^2 or K^2. It is found that the rate of heat transfer at the disk η= 0 increases with increase in either m or K. On the other hand the rate of heat transfer at the disk η= 1 increases with increase in K but decreases with increase in m.

关键词： Non-coincident Viscous fluid Torque ,Hydromagnetic

Online Induction of Probabilistic Real-Time Automata

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Journal of Computer Science & Technology 2014年第3期29卷 345-360页

作者： jana Schmidt Stefan Kramer Technische Universitt mnchen Institut fr Informatik/I12Boltzmannstr. 385748 Garching b. MnchenGermany Johannes Gutenberg-Universitt mainz Institute for Computer ScienceStaudingerweg 955128 MainzGermany

The probabilistic real-time automaton （PRTA） is a representation of dynamic processes arising in the sciences and industry. Currently, the induction of automata is divided into two steps： the creation of the prefix tree acceptor （PTA） and the merge procedure based on clustering of the states. These two steps can be very time intensive when a PRTA is to be induced for massive or even unbounded datasets. The latter one can be efficiently processed, as there exist scalable online clustering algorithms. However, the creation of the PTA still can be very time consuming. To overcome this problem, we propose a genuine online PRTA induction approach that incorporates new instances by first collapsing them and then using a maximum frequent pattern based clustering. The approach is tested against a predefined synthetic automaton and real world datasets, for which the approach is scalable and stable. moreover, we present a broad evaluation on a real world disease group dataset that shows the applicability of such a model to the analysis of medical processes.

关键词： probabilistic real-time automata online induction maximum frequent pattern based clustering

Hall effects on hydromagnetic flow on an oscillating porous plate

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Applied mathematics and mechanics(English Edition) 2009年第4期30卷 503-512页

作者： S.L.maji A.K.Kanch m.Guria R.N.jana Department of Applied mathematics Vidyasagar University

In this paper, an analysis is made on the unsteady flow of an incompressible electrically conducting viscous fluid bounded by an infinite porous flat plate. The plate executes harmonic oscillations at a frequency n in its own plane. A uniform magnetic field Ho is imposed perpendicular to the direction of the flow. It is found that the solution also exists for blowing at the plate. The temperature distribution is also obtained by taking viscous and Joule dissipation into account. The mean wall temperature θo（O） decreases with the increase in the Hall parameter m. It is found that no temperature distribution exists for the blowing at the plate.

关键词： Hall effects oscillation resonance heat transfer and mean temperature