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81.
IM Kapetanovic CD Torchin CD Thompson TA Miller PJ McNeilly TL Macdonald HJ Kupferberg JL Perhach RD Sofia JM Strong 《Canadian Metallurgical Quarterly》1998,26(11):1089-1095
To gain insights into the different forms of modified amyloid beta peptides (A beta) in the Alzheimer disease (AD) and Down syndrome (DS) brain, we used two-site ELISAs with antibodies specific for isomerized (i.e. A beta with L-isoaspartate at positions 1 and 7) and pyroglutamate-modified (i.e. A beta beginning with pyroglutamate at position 3) forms of A beta to quantitate the levels of these different A beta peptides in formic acid extracts of AD and DS frontal cortex. Despite variations in the proportions of distinct forms of A beta in AD and DS frontal cortex, the major species of A beta in these samples were A betaN3(pyroGlu)-42 as well as A beta x-42 (where x is a residue at position 2 or less in A beta), whereas isomerized A beta was a minor species. Further, the levels of isomerized and pyroglutamate-modified forms of A beta terminating at amino acid 42 were higher than those ending at amino acid 40. The abundance of the distinct forms of A beta reported here in formic acid extracts of AD and DS frontal cortex suggests that these A beta species could play important roles in the deposition of A beta in AD and DS brains. 相似文献
82.
RD Sofia 《Canadian Metallurgical Quarterly》1977,7(2):289-297
Depression of the hepatic microsomal enzyme system(s) in adjuvant-induced polyarthritis (AIP), a chronic inflammation model, has been confirmed indirectly by the enhancement of hexobarbital Na-induced sleeping time and extended for the first time to zoxazolamine-induced paralysis. In addition, barbital Na-induced anesthesia was increased during the course of AIP development, indicating that the CNS of these rats appears to be more sensitive to drug effects, since this barbiturate is excreted virtually unmetabolized. Most likely because of these effects, LD50 values for acetylsalicylic acid, phenylbutazone and indomethacin in AIP rats decreased in terms of mg/kg (increased toxicity) as the disease became more severe (Day 21) since they are known ultimately to be metabolized by the liver. On the other hand, the toxicity of a new non-steroidal anti-inflammatory agent, meseclazone, was not altered significantly in AIP. This is most likely due to the fact that its near total conversion to 5-chlorosalicylic acid has been shown to occur by hydrolytic cleavage as it pases through the intestinal wall with litter hepatic involvement. Finally, carrageenan edema, a model of acute inflammation, did not affect barbiturate sleeping times of zoxazolamine paralysis, nor were any of these drugs studied more lethal in this disease state. 相似文献
83.
Impact of diet supplemented with microencapsulated condensed tannins on cow milk nutritional profile
Attilio Matera Lucia Sepe Silvia Vincenzetti Roberta Tolve Nicola Condelli Salvatore Claps Francesco Genovese Annamaria Ricciardi Teresa Zotta Teresa Scarpa Maria Antonietta Di Napoli Giulia Francesca Cifuni Paolo Polidori Giuseppe Santini Luciano Scarano Giuseppe Altieri Giovanni Carlo Di Renzo Sofia Renzi Marilisa Giavalisco Fernanda Galgano 《International Journal of Dairy Technology》2023,76(4):813-827
Feed production systems should consider more sustainable solutions to reduce the pressure on earth's finite resources. In this work, we investigated the effect of microencapsulated condensed tannins (MCTs)-enhanced diet on the cow milk characteristics. The diet reduced the urea content, while preserved and the n-3 and n-6 portion of fatty acids. Aside from the rising of vitamin C level, MCTs had a negative effect on the amount of B group vitamins. MCTs may be considered a promising feed supplement that offers a good trade-off in terms of milk chemical quality while increasing the environmental sustainability of cattle livestock. 相似文献
84.
Li Day Mi Xu Sofia K. Øiseth Yacine Hemar Leif Lundin 《Food and Bioprocess Technology》2010,3(6):928-934
A range of thermal and mechanical processes were used to create dispersions with different particle morphologies, i.e., systems that contain primarily plant cell wall clusters with an average particle size (d(0.5)) of ~200 µm, single cells ((d(0.5)?=?~70 µm) or cell fragments (d(0.5)?=?~40 µm). The small and large deformation rheology (viscoelastic properties and flow properties) of these dispersions, with a range of total solid contents covering textures varying from a fluid to a paste, were determined. The particle dispersions showed weak gel-like behaviour. Their elastic modulus (G′) as a function of total solid content exhibited three regions of different rheological behaviours. The particles formed particulate colloidal networks at relatively low solid content. The interaction of particles contributed to the sharp increase in the elastic modulus of the dispersion in the concentrated region. Further packing of particles beyond the critical packing volume fraction, caused the G′ for the ‘cluster-cell’ and the ‘single-cell’ dispersions to reach a plateau value. This is due to particle deformation resulting in changes in their microstructure and their ability to pack closely. Plant particle dispersions displayed abrupt yielding at the critical stress with a 3–4 order decrease in viscosity and high yield stress at low solids due to the formation of particulate colloidal network. 相似文献
85.
Yi‐Chun Huang A. Timothy Royappa Sofia Tundel Kana Tsukamoto Venkatanarayanan Sharma 《应用聚合物科学杂志》2009,111(5):2275-2278
Polyglycidol (PGly), a hyperbranched water‐soluble polyether with numerous terminal hydroxyl groups, has structural similarities with polyethylene glycol. Our laboratory is exploring drug delivery using hyperbranched PGly‐cytokines conjugates. Using human peripheral blood mononuclear cells and a tumor derived human B cell line, HBL‐1; various PGly concentrations were tested for cytotoxicity. Our data indicated that hyperbranched PGly was similar in toxicity to PEG 8000, a commercial polymer. It was concluded that hyperbranched PGly did not exhibit significant cytotoxicity and showed promise for use as a biocompatible polymer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
86.
Wang G Rodahl M Edvardsson M Svedhem S Ohlsson G Höök F Kasemo B 《The Review of scientific instruments》2008,79(7):075107
We have developed an instrument for surface interaction studies, which combines a newly invented four detector optical reflectometry setup with quartz crystal microbalance with dissipation (QCM-D) monitoring. The design is such that data from both techniques can be obtained simultaneously on the same sensor surface, with the same signal-to-noise ratio and time resolution, as for the individual techniques. In addition, synchronized information about structural transformations, molecular mass, and the hydration of thin films on solid surfaces can be obtained on the same specimen, as validated by monitoring the formation of supported lipid bilayers on a silica-coated QCM sensor surface. We emphasize that the optical (molecular) mass can be separated from the acoustic mass including hydrodynamically coupled solvent, which means, in turn, that the amount of solvent sensed by the QCM-D technique can be dynamically resolved during adsorption processes. In addition, the advantage/necessity to use four, compared to two, detector reflectometry is emphasized. 相似文献
87.
Patricia R. Barbosa Yugandhar Sarkale Edwin K. P. Chong Yun Li Sofia Suvorova Bill Moran 《Asian journal of control》2019,21(4):1630-1643
We investigate the challenging problem of integrating detection, signal processing, target tracking, and adaptive waveform scheduling with lookahead in urban terrain. We propose a closed‐loop active sensing system to address this problem by exploiting three distinct levels of diversity: (1) spatial diversity through the use of coordinated multistatic radars; (2) waveform diversity by adaptively scheduling the transmitted waveform; and (3) motion model diversity by using a bank of parallel filters matched to different motion models. Specifically, at every radar scan, the waveform that yields the minimum trace of the one‐step‐ahead error covariance matrix is transmitted; the received signal goes through a matched‐filter, and curve fitting is used to extract range and range‐rate measurements that feed the LMIPDA‐VSIMM algorithm for data association and filtering. Monte Carlo simulations demonstrate the effectiveness of the proposed system in an urban scenario contaminated by dense and uneven clutter, strong multipath, and limited line‐of‐sight. 相似文献
88.
Ioan Alin Bucurica Ion V Popescu Cristiana Radulescu Gheorghe Valerica Cimpoca Ioana-Daniela Dulama Sofia Teodorescu Ion Valentin Gurgu Dorin Dacian Let 《Bulletin of Materials Science》2018,41(3):71
Quartz crystal microbalance (QCM) is known as a very sensitive device used for determination of mass quantity adsorbed on sensor surface. Its detection limits are in the range of ng cm\(^{-2}\). The adsorption mechanism of metallic nanoparticles on QCM sensor was investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). This study aims to highlight the importance of QCM applications in nanoparticles deposition field. The layers formed through adsorption process, induced by the oscillations of the QCM sensor, were investigated by AFM for surface topography and for particle mean size values. The morphology of layers and nanoparticles dimensions were determined by SEM. For a more complex investigation of the nanoparticles adsorption mechanism, the chemical composition of layers was achieved using SEM coupled with energy dispersive X-ray spectrometer (SEM-EDS). This preliminary research involved a new approach in characterization of metallic nanoparticles layers to achieve functional assembled monolayers. 相似文献
89.
Processing Parameters on the Extraction of Olive Pomace Oil and Its Bioactive Compounds: A Kinetic and Thermodynamic Study 下载免费PDF全文
The effect of temperature (40–60 °C), solid/liquid ratio (1/4–1/12 g mL?1), and agitation speed (AS) (100–800 rpm) on the extraction yield of olive pomace oil and on the recovery of its unsaponifiable matter (USM) during extraction were studied. Two kinetic models were tested to correlate the experimental data; the first proposed by So and Macdonald and the second by Sulaiman et al. The two models adequately describe the extraction process of both oil and USM. Higher extraction temperatures, solid to liquid ratios, and AS led to increased oil yield and favored USM in the extracted oil, and also increased the calculated mass transfer coefficients of the extraction. Changes in enthalpy and entropy were found to be positive while change in free energy was negative, indicating that the process was endothermic, irreversible, and spontaneous. Under equilibrium conditions, the oil yield was increased by a factor of approximately 1.096 and 1.054 for the model of So and Macdonald and Sulaiman et al., respectively, for every 10 °C rise in temperature. 相似文献
90.
de Carlan L Price R Chartier JL Kodeli I Siebert B Henninger J Posselt J Gualdrini G Agosteo S Bedogni R Bordy JM Cassette P Ferrari P Gomez Ros JM Grosswendt B Lacoste V Pola A Rollet S Schultz F Simakov SP Tanner R Terrissol M Zankl M 《Radiation protection dosimetry》2008,131(1):15-23
In the frame of the EU Coordination Action CONRAD (coordinated network for radiation dosimetry), WP4 was dedicated to work on computational dosimetry with an action entitled 'Uncertainty assessment in computational dosimetry: an intercomparison of approaches'. Participants attempted one or more of eight problems. This paper presents the results from problems 4-8-dealing with the overall uncertainty budget estimate; a short overview of each problem is presented together with a discussion of the most significant results and conclusions. The scope of the problems discussed here are: the study of a (137)Cs calibration irradiator; the manganese bath technique; the iron sphere experiment using neutron time-of-flight technique; the energy response of a RADFET detector and finally the sensitivity and uncertainty analysis for the recoil-proton telescope discussed in the companion paper. 相似文献