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Pedersoli E Capotondi F Cocco D Zangrando M Kaulich B Menk RH Locatelli A Mentes TO Spezzani C Sandrin G Bacescu DM Kiskinova M Bajt S Barthelmess M Barty A Schulz J Gumprecht L Chapman HN Nelson AJ Frank M Pivovaroff MJ Woods BW Bogan MJ Hajdu J 《The Review of scientific instruments》2011,82(4):043711
We present a compact modular apparatus with a flexible design that will be operated at the DiProI beamline of the Fermi@Elettra free electron laser (FEL) for performing static and time-resolved coherent diffraction imaging experiments, taking advantage of the full coherence and variable polarization of the short seeded FEL pulses. The apparatus has been assembled and the potential of the experimental setup is demonstrated by commissioning tests with coherent synchrotron radiation. This multipurpose experimental station will be open to general users after installation at the Fermi@Elettra free electron laser in 2011. 相似文献
44.
Nande VS Barabde UU Morkhade DM Patil AT Joshi SB 《Drug development and industrial pharmacy》2007,33(10):1090-1100
The PEGylated derivatives of rosin-PD-1 and PD-2 synthesized and characterized earlier (Nande et al., 2006) were investigated as potential materials for sustained release microsphere prepared by emulsion solvent evaporation method using diclofenac sodium (DCS) as model drug. All the microspheres exhibited smooth surfaces intercepted by pores; their sizes (d(90)) ranged between 11-24 microm. The entrapment efficiency (< 80%) of the microspheres increased proportionally with derivative concentration. Presence of solvent like isopropyl alcohol or dichloromethane rendered the microspheres with large sizes but with reduced drug entrapment. Microspheres with small size were obtained at an optimum viscosity of liquid paraffin; any change lead to increase in the particle size. Magnesium stearate was found to be most suitable detackifier in the present system. The drug release was directly related to the particle size--small sized microspheres released drug at a faster rate. The dissolution data complied with Higuchi equation while the mechanism of drug release was Fickian diffusion (n approximately 0.5). Controlled inhibition of edema, as tested by hind paw edema method, was observed for 10 h when the microspheres were administered intraperitoneally. The present study found the derivatives as promising materials for preparing microspheres for sustained delivery of DCS. 相似文献
45.
We present a structural study of Pt(3)Ni nanoctahedron superlattice, prepared through both drop-casting and controlled solvent evaporation approaches. In this superlattice system containing ~10.6 nm side-length Pt(3)Ni nanoctahedra, we observed a body-centered cubic (bcc) packing structure in both local superlattices and statistically averaged superlattice ensembles using transmission electron microscopic tomography and grazing-incidence small-angle X-ray scattering techniques, respectively. Within the superstructure, it was directly observed that nanoctahedra are orientated along the superstructure axes through sharing their vertices. We found that this arrangement of a bcc superstructure with nanoctahedra connecting through their vertices is dependent on neither the processing pathway nor the substrate under our experimental conditions. With such a very low packing density and ultrahigh surface area, this type of self-organized superstructure possesses unique features for future applications. 相似文献
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47.
A general cone-beam reconstruction algorithm 总被引:17,自引:0,他引:17
Considering the characteristics of the X-ray microscope system being developed at SUNY at Buffalo and the limitations of available cone-beam reconstruction algorithms, a general cone-beam reconstruction algorithm and several special versions of it are proposed and validated by simulation. The cone-beam algorithm allows various scanning loci, handles reconstruction of rod-shaped specimens which are common in practice, and facilitates near real-time reconstruction by providing the same computational efficiency and parallelism as L.A. Feldkamp et al.'s (1984) algorithm. Although the present cone-beam algorithm is not exact, it consistently gives satisfactory reconstructed images. Furthermore, it has several nice properties if the scanning locus meets some conditions. First, reconstruction within a midplane is exact using a planar scanning locus. Second, the vertical integral of a reconstructed image is equal to that of the actual image. Third, reconstruction is exact if an actual image is independent of rotation axis coordinate z. Also, the general algorithm can uniformize and reduce z-axis artifacts, if a helix-like scanning locus is used. 相似文献
48.
Free-stall dimensions: effects on preference and stall usage 总被引:1,自引:0,他引:1
In 2 experiments, free-stall dimensions were examined to determine how they affected stall preference, usage, cleanliness, and milk production in Holstein dairy cattle. In experiment 1, stall width (112 or 132 cm) and stall length (229 and 274 cm from curb to wall) were compared in a 2 x 2 factorial arrangement of stall treatments using 15 individually housed, non-lactating animals. Cows showed no clear preference for stall size as measured by lying time. When animals had no choice between stalls, average lying time was higher in the wide stalls than in the narrow stalls (10.8 vs. 9.6+/-0.3 h/24 h). Both length and width affected time spent standing with only the front hooves in the stall; total stall area is best explained by the variation associated with this behavior. In experiment 2, 27 lactating dairy cattle were alternately housed with access to stalls of 106, 116, or 126 cm in width using a cross-over design with exposure to each treatment lasting 3 wk. Animals spent an additional 42 min/24 h lying in stalls measuring 126 cm in width compared with stalls with only 106 cm between partitions. Free-stall width influenced the time spent standing with the front 2 hooves in the stall; animals averaged 58 min/24 h in the widest stalls and 85 min/24 h in the narrowest stalls. The amount of time spent standing with all 4 hooves in the stall tended to be longer in wider stalls, and these stalls were also most likely to become soiled with feces. Stall width did not affect the number of lying events or milk production. In conclusion, animals spent more time lying down, and less time was spent standing with only the front hooves in larger stalls, but larger stalls were also more likely to become soiled. 相似文献
49.
Radishes (Raphanus sativus L.) are members of the cruciferous vegetable family that contain many classes of biologically active phytochemicals. This study determined the phytochemical composition of the sprouts and mature taproots of 8 radish varieties. Radish sprouts contained significantly greater concentrations of glucosinolates (3.8-fold) and isothiocyanates (8.2-fold) than the mature radish taproot and also contained significantly greater concentrations of phenolics (on average 6.9-fold). The anthocyanin concentrations of the mature radish taproot were significantly greater than in the sprouts of red, pink, and purple varieties. The primary anthocyanidins present in the red and pink radish varieties were pelargonidin and delphinidin, while the primary anthocyanidin in the purple radish variety was cyanidin. Radish sprouts were between 9- and 59-fold more potent than the corresponding mature taproot at activating the antioxidant response element (ARE) in a stably transfected hepatoma cell line. The ARE activity of the radish sprouts and mature taproots was significantly correlated with the total isothiocyanate concentration of the radishes. Practical Application: Understanding the influence variety and developmental stage has on the biological activity of cruciferous vegetables provides important information for further studies examining the in vivo effects of radish treatment and foundation for providing recommendations to reduce the risk of chronic disease through dietary intervention. 相似文献
50.
Tomy GT Pleskach K Ismail N Whittle DM Helm PA Sverko E Zaruk D Marvin CH 《Environmental science & technology》2007,41(7):2249-2254
The extent of bioaccumulation of the syn- and anti-isomers of Dechlorane Plus (DP) is assessed in archived food web samples from Lake Winnipeg and Lake Ontario. Concentrations of the isomers were determined using purified analytical solutions of individual isomers as opposed to the technical mixture. The syn-isomer was consistently detected in all samples from both lakes; the anti-isomer was detected in all Lake Ontario samples, but only 45% of the samples from Lake Winnipeg. The pattern of bioaccumulation was different for the isomers in Lake Winnipeg. The anti-isomer was dominant in higher trophic level (TL) organisms like walleye [arithmetic mean +/- 1 x standard error: 730 +/- 120 pg/g, lipid weight (1w)] and goldeye (760 +/- 170 pg/g, Iw) while the syn-isomer dominated the lower TL organisms like zooplankton (550 +/- 40 pg/g, Iw) and mussels (430 +/- 140 pg/g, Iw). In Lake Ontario, the extent of bioaccumulation of the isomers and concentrations was greatest in the lower TL benthic organism, Diporeia (syn, 1307 +/- 554; and anti, 3108 +/- 898 pg/g Iw) and also high in zooplankton (syn, 719; and anti, 1332 pg/g Iw). This suggests that the isomers are bioavailable in sediment and that, despite their molecular size, diffusion from the water column into zooplankton can occur. Differences in the mean fractional abundance of the anti-isomer (mean fanti = mean concentration of the anti-isomer divided by sum of mean syn- and anti-concentrations) were pronounced in sediments between lakes (Lake Winnipeg mean fanti = 0.610, Lake Ontario mean fanti = 0.860) and the extent of enrichment (anti-) and depletion (syn-) of the isomers were more marked in Lake Winnipeg biota. There were also differences in the biomagnification potentials, as measured bythe trophic magnification factor (TMF), between the isomers in the Lake Winnipeg food web; no statistically significant TMFs for either isomer were found for the 相似文献