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111.
112.
Dingari NC Barman I Singh GP Kang JW Dasari RR Feld MS 《Analytical and bioanalytical chemistry》2011,400(9):2871-2880
Although several in vivo blood glucose measurement studies have been performed by different research groups using near-infrared
(NIR) absorption and Raman spectroscopic techniques, prospective prediction has proven to be a challenging problem. An important
issue in this case is the demonstration of causality of glucose concentration to the spectral information, especially as the
intrinsic glucose signal is smaller compared with that of the other analytes in the blood–tissue matrix. Furthermore, time-dependent
physiological processes make the relation between glucose concentration and spectral data more complex. In this article, chance
correlations in Raman spectroscopy-based calibration model for glucose measurements are investigated for both in vitro (physical
tissue models) and in vivo (animal model and human subject) cases. Different spurious glucose concentration profiles are assigned
to the Raman spectra acquired from physical tissue models, where the glucose concentration is intentionally held constant.
Analogous concentration profiles, in addition to the true concentration profile, are also assigned to the datasets acquired
from an animal model during a glucose clamping study as well as a human subject during an oral glucose tolerance test. We
demonstrate that the spurious concentration profile-based calibration models are unable to provide prospective predictions,
in contrast to those based on actual concentration profiles, especially for the physical tissue models. We also show that
chance correlations incorporated by the calibration models are significantly less in Raman as compared to NIR absorption spectroscopy,
even for the in vivo studies. Finally, our results suggest that the incorporation of chance correlations for in vivo cases
can be largely attributed to the uncontrolled physiological sources of variations. Such uncontrolled physiological variations
could either be intrinsic to the subject or stem from changes in the measurement conditions. 相似文献
113.
We here experimentally demonstrate that gyration modes of coupled vortices can be resonantly excited primarily by the ac current in a pair of ferromagnetic disks with variable separation. The sole gyration mode clearly splits into higher and lower frequency modes via dipolar interaction, where the main mode splitting is due to a chirality sensitive phase difference in gyrations of the coupled vortices, whereas the magnitude of the splitting is determined by their polarity configuration. These experimental results show that the coupled pair of vortices behaves similar to a diatomic molecule with bonding and antibonding states, implying a possibility for designing the magnonic band structure in a chain or an array of magnetic vortex oscillators. 相似文献
114.
The rate coefficients for the reaction OH + CH3CH2CH2OH → products (k1) and OH + CH3CH(OH)CH3 → products (k2) were measured by the pulsed‐laser photolysis–laser‐induced fluorescence technique between 237 and 376 K. Arrhenius expressions for k1 and k2 are as follows: k1 = (6.2 ± 0.8) × 10?12 exp[?(10 ± 30)/T] cm3 molecule?1 s?1, with k1(298 K) = (5.90 ± 0.56) × 10?12 cm3 molecule?1 s?1, and k2 = (3.2 ± 0.3) × 10?12 exp[(150 ± 20)/T] cm3 molecule?1 s?1, with k2(298) = (5.22 ± 0.46) × 10?12 cm3 molecule?1 s?1. The quoted uncertainties are at the 95% confidence level and include estimated systematic errors. The results are compared with those from previous measurements and rate coefficient expressions for atmospheric modeling are recommended. The absorption cross sections for n‐propanol and iso‐propanol at 184.9 nm were measured to be (8.89 ± 0.44) × 10?19 and (1.90 ± 0.10) × 10?18 cm2 molecule?1, respectively. The atmospheric implications of the degradation of n‐propanol and iso‐propanol are discussed. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 42: 10–24, 2010 相似文献
115.
IEC information received through VHF RB measurements has been analyzed over the anomaly crest region of Guwahati (92° E, 26° N, 15° N geo.mag) along with a few low/low-mid latitude observations for understanding the roles of influx of plasma to anomaly crest regions, from equatorward and poleward processes during geomagnetically disturbed situations. The conditions leading to inflow of plasma to equatorial anomaly crest region or inhibition of such processes have been described in the paper through systematic analysis of disturbed day (free from sudden commencements) ionospheric electron content (IEC) variations at different temporal situtions. The storm-induced effects in relation to the development of the above conditions have also been examined for moderate and moderately severe isolated storm cases. Finally the paper deals with a few severe storms. The storm-triggered IEC features indicate inhibition or suppression of plasma dumping process at anomaly crests, through equatorial anomaly phenomenon. During winter and many equinoxial storms, the compression effect pushes this station away from the region where effective dumping of ionization from the equator is expected. Diffusion of plasma from the polar region to the crest area has also been observed through penetration of the eastward electric field during many disturbed situations. Depletion of noontime density during winter and equinoxial months and enhancement of the same during summer geomagnetically active situations are examined through anomaly compression (or inhibition) process as well as plasma replenishment through the equatorward wind.Published from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 3, pp. 263–275, March, 1996. 相似文献
116.
A. Monmayrant A. Arbouet B. Girard B. Chatel A. Barman B. J. Whitaker D. Kaplan 《Applied physics. B, Lasers and optics》2005,81(2-3):177-180
Time shaping of ultra-short visible pulses has been performed using a specially designed acousto-optic programmable dispersive filter of 50% efficiency at the output of a two-stage non-collinear optical parametric amplifier. The set-up is compact and reliable. It provides a tunable shaped source in the visible with unique features: a 4-ps shaping window with preserved tunability over 500–650 nm, and pulses as short as 30 fs. Several-μJ output energy is easily obtained. 相似文献
117.
Deb Argha Gazi Mahasin Bhoumik Gopa Naskar Arindam Barman Chiranjib 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):375-384
Air radon survey was carried out at different underground locations at Kolkata using radon monitor. Average radon concentration for basements was found to be 22.70 ± 1.12 Bq/m3 with maximum 59.00 ± 7.18 Bq/m3 and minimum 8.50 ± 3.14 Bq/m3. Average level for sub-ways was 23.05 ± 2.59 Bq/m3 fluctuating between maximum 39.00 ± 1.24 Bq/m3 and minimum 13.50 ± 1.78 Bq/m3. In comparison, open air background at basement entrance was 19.44 ± 1.06 Bq/m3 and subway entrance was 18.58 ± 1.14 Bq/m3. Annual effective dose was calculated to assess probable health risk. Radon concentration level and annual effective dose were found well below safe levels recommended by International Agencies WHO and UNSCEAR.
相似文献118.
Gopa Barman Pranab Haldar Neelanjan Dutta Jayanta K. Ray 《Journal of heterocyclic chemistry》2011,48(2):463-467
Substituted pyrrolidine derivatives were synthesized in high yield by NaBH4/I2 mediated chemoselective reduction of N‐aryl‐γ‐lactam and N‐aryl‐thio‐γ‐lactam‐2,2‐dicarboxylate. With excess NaBH4/I2, carbonyl functionality of the ester groups remained unchanged. J. Heterocyclic Chem., (2011). 相似文献
119.
Anup Kumar Pawan Heera Pankaj Sharma P.B. Barman Raman Sharma 《Journal of Non》2012,358(23):3223-3228
Compositional dependence of optical parameters in thermally evaporated amorphous Se80.5Bi1.5Te18 ? yAgy (for y = 0, 1.0, 1.5 and 2.0 at.%) quaternary thin films has been studied using well established Swanepoel method. The optical properties like, refractive index (n), extinction coefficient (k), absorption coefficient (α) and optical band gap (Eg) have been determined from the transmission spectra in the spectral range from 500 to 2500 nm. The optical band gap (Eg) has been estimated by using Tauc's extrapolation method and is found to increase with an increase in the Ag concentration. Present study shows that the refractive index, extinction coefficient and optical band gap increase with the increasing Ag content which is in agreement with the earlier studies. While the increase in the refractive index with Ag content over the entire spectral range can be attributed to the increased polarizability of larger Ag atomic radius (153 pm) compared to the Te atomic radius (135 pm), the increase in the optical band gap with increasing Ag concentration is correlated to an increase in the cohesive energy and decrease in the electronegativity of the films under study. The dielectric constant and optical conductivity (σ) of the thin films under study are also found to increase with the Ag concentration. 相似文献
120.
We express the number of ${\mathbb{F}_q}$ -points on the hyperelliptic curve ${\alpha{y}^2=\beta{x}^f + \gamma}$ in terms of Gaussian hypergeometric series. We also find some special values of ${{_{2}}F_1}$ -Gaussian hypergeometric series containing characters of order 3 and 4 as parameters. 相似文献