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151.
In this work, we present the concept, design and implementation of a new software to visualize and segment 3-dimensional medical
data. The main goal was to create a platform that would allow trying out new approaches and ideas while staying independent
from hardware and operating system, being especially useful for interdisciplinary research groups. A special focus will be
given on fast and interactive volume visualization, and a survey on the use of Virtual Reality (VR) and especially haptic/force
feedback in medical applications will be provided. 相似文献
152.
Sensitized emission FRET detection method based on three-filter fluorescence microscopy is widely used and more suitable for live cell FRET imaging and dynamic protein-protein interaction analysis. But when it is applied to detect two proteins interaction in living cells, this intensity-based detection method is complicated by many experimental factors such as spectral crosstalk and spectral bleed-through and variable donor to acceptor concentration ratio. There are several FRET algorithms developed recently to correct those factors in order to quantitatively gauge and compare FRET signals between different experimental groups. But the algorithms are often difficult to choose when they are applied to certain experiments. In this research, we use c-Fos/c-Jun as a simple hetero-dimer interaction model to quantitatively detect and compare the FRET signals based on the following widely used sensitized emission FRET algorithms: N(FRET) , FRET(N) , FR, FRET(R) , E(app) and E(EFF) . We optimized the donor to acceptor concentration ratio range for the above FRET algorithms and facilitate their use in accurate FRET signal determination based on the three-filter FRET microscopy. 相似文献
153.
Mobile application offloading is an efficient technique to unload the burden of intensive computation from thin clients to powerful servers. In a mobile offloading system, cloud computing is utilized to complete some heavy tasks which are migrated from resource-constrained mobile devices to the Cloud. To assure system performance, the quality of the wireless network connection plays an important role. In previous work we experimentally explored the impact of packet loss and delay in wireless networks on the completion time of an offloading task. We investigated a local restart mechanism to mitigate these effects. In the presence of unreliable communication, once the waiting time for the response of a cloud server exceeds a given threshold, exploiting the local resources of a mobile client can accelerate the task completion.In this paper, we upgrade the restart mechanism by allowing several offloading retries before a job eventually is locally restarted and finally completed in the client device itself. This is an adaptive restart scheme which aims first at completing the job using restart with offloading. If several successive offloading attempts fail the job is completed locally. Adaptively selecting the right retry threshold and automatically restarting at the appropriate moment can balance out undesired effects. This paper extends Wang and Wolter (Proceedings of the 6th ACM/SPEC international conference on performance engineering. ACM, pp 3–13, 2015) by adding an adaptive retry scheme, a mathematical derivation of the optimal limit for offloading attempts so as to minimize the task completion time using a greedy method, and by the results of a practical evaluation study which shows the efficiency and benefits of the adaptive restart scheme. 相似文献
154.
The adhesion of three carbon fibers, AS1, AS4, and XAS to thermosetting and thermoplastic polymers has been investigated using the single, embedded filament test. All three fiber types exhibited strong adhesion to the thermosets (epoxies) whereas only the XAS bonded strongly to the thermoplastics. Common explanations for low adhesion, such as weak boundary layers and surface roughness, were investigated and shown not to be responsible for the differences in adhesion. Different levels of fiber surface treatment and various organic sizings also had no effect. Surface analysis of the fibers using XPS and retention time chromatography indicate a subtle difference in the surface chemical constitution of the three fibers but the exact nature of these differences was not determined. 相似文献
155.
Differences among Expert Judgments of Fish Habitat Suitability and Implications for River Management
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Expert judgment is regularly used in ecology for assessing the suitability of habitats, in particular of rare or endangered species or species with limited empirical data. Yet, differences in expert judgment of habitat suitability and consequent implications for ecosystem management have not been evaluated and are largely ignored. Here, we evaluated the variability of 13 expert judgments and the related uncertainty in hydraulic habitat suitability modelling using the riverine fish species Phoxinus phoxinus as a model species. We found (i) the highest agreement among experts identifying the best and fully unsuited habitat conditions, but (ii) that disagreement among experts is surprisingly large, (iii) with largest differences related to the experts' perception of flow velocity and (iv) that semi‐suitable transition areas between high and low habitat suitability are most susceptible to disagreements. We emphasize that expert judgment of habitat suitability is useful for many applications and especially highly suitable habitats would be reliably identified by experts. However, expert judgment‐based assessments should be iterative processes that include both different experts and feedback on the potential effects of their assessments. Furthermore, we recommend that expert judgment should not replace data‐driven empirical ecology but its benefits can rather complement it. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
156.
Preparation and characterization of functional poly(ethylene glycol) surfaces for the use of antibody microarrays 总被引:1,自引:0,他引:1
Protein microarrays serve as measurement platforms for multianalytical applications. Small molecules, DNA, proteins, and cells are determined quantitatively. Amino-PEG surfaces can be a smart functional platform for protein microarrays with high signal-to-noise ratios. An effective step-by-step chemistry is developed for uniform presentation of terminal functional groups at each monolayer. Poly(ethelene glycol diamine) 2000 (DAPEG, 2000 g/mol) films were prepared onto silanized glass slides presenting epoxy groups. The uniformity of the grafted DAPEG monolayer is characterized by a chemiluminescence reaction using a chemiluminescence microarray reader with automated reagent supply and a horseradish peroxidase (HRP)/luminol reporter system. An intensity line plot on the horizontal axis was generated. The chemiluminescence intensities vary in a range of 2.6%. Antibodies against HRP as model system were immobilized on N-hydroxysuccinimide activated DAPEG layers by means of a microcontact roboter system. Chemiluminescence signals of bound HRP are detected at each spot with a standard deviation of 2.9%. The maximum antibody concentration that can be immobilized at the surface is determined with 1 mg/mL. Additives for an optimal spotting buffer are also studied. The use of the block-copolymer Pluronic F127 as antibody stabilizer is as well investigated as trehalose for the prevention of spot evaporation. The lowest detectable HRP concentration is 0.08 ng/mL determined on anti-HRP antibody microarrays. This study demonstrates how surfaces and analytical parameters for protein microarray applications can be characterized with a chemiluminescence readout system using a HRP reporter system. 相似文献
157.
Dorren B.H.P. Silov A.Yu. Leys M.R. Dukers D.M.H. Haverkort J.E.M. Maat D.H.P. Zhu Y. Groen F.H. Wolter J.H. 《Quantum Electronics, IEEE Journal of》2000,36(3):317-324
We have theoretically designed and realized a phase shifter for a low-loss Mach-Zehnder interferometric switch. The phase shifter is based on 0.85% tensile strained InGaAs-InP chopped quantum-well material. We realized a Mach-Zehnder interferometric switch with polarization-independent switching voltages as low as 3.3±0.05 V at 1525 nm for a switch with a 4-mm-long phase shifting section. The wavelength sensitivity of the switch is 0.036 V/nm for TE and 0.053 V/nm for TM polarization. Calculations of the electro-refraction in the -0.85% strained chopped quantum-well (QW) material based on the 4×4 Luttinger-Kohn Hamiltonian show that the electro-refraction due to the quantum-confined Stark effect (QCSE) for TM polarization is equal to the sum of the mutually comparable QCSE electro-refraction and the Pockels effect for TE polarization in waveguides along the [11¯0] axis. Our first-principle model for calculating the electro refraction is an accurate design tool for predicting device performance in complicated layer structures. The shortest possible phase shifter with a <-25 dB crosstalk penalty due to electro-absorption unbalance can be as short as 2.2 mm. This compact switch is predicted to have a 6-V switching voltage and a 15-nm window for polarization-independent switching with a <-25-dB crosstalk penalty. With a slight increase of the strain, this chopped QW material can be used for polarization independent switching around 1550 nm 相似文献
158.
A representative number of 11 inland waterways of the north-eastern lowlands in Germany was surveyed between 1992 and 1994 using different fishing methods. Data were pooled for sites and waterways. From the 234 sites investigated, a total of 53 432 fish were collected and 29 species recorded. The typical fish assemblage of the waterways was subdivided into three defined classes according to presence and relative abundance of species: reference, accompanying and minor species. The fish fauna was characterized by the dominance of roach (Rutilus rutilus) and perch (Perca fluviatilis). Both fish species showed a mean abundance of 70·61 % (SD=10·91 %), whereas more than half of the species recorded had a relative abundance < 1%. Two trends could be identified in the fish assemblage owing to human influences: an increase in the dominance of roach and perch and a decrease in species number. In particular, intolerant fish with a preference for sand or gravel substrata and current diversity have become rare and endangered. The typical fish assemblage of waterways in the lowlands differed from that in the uplands with respect to the higher abundance of rheophilic lithophils in the uplands. © 1997 John Wiley & Sons, Ltd. 相似文献
159.
Marco Thom? Guntram Wagner Benjamin Stra? Bernd Wolter Sigrid Benfer Wolfram Fürbeth 《材料科学技术学报》2018,34(1):163-172
In this work, the joining of aluminum to steel was conducted by ultrasound enhanced friction stir welding (USE-FSW). The power ultrasound was introduced into one of the metal sheets by an ultrasonic roll seam module synchronously to the FSW-process. The effect of the ultrasound on the resulting welds, their microstructure and their corrosion properties was investigated by light and scanning electron microscopy and corrosion investigations. The USE-FSW-joints showed less and smaller steel particles in the nugget zone as well as a thinner continuous intermetallic phase of FeAl3 at the interface. The nondestructive testing method of computed laminography proved the observations made by optic microscopy due to non-porous joints for both techniques. Corrosion investigations showed only low corrosion current densities and no enhanced galvanic corrosion for the EN AW-6061/DC04-hybrid joints in sodium chloride solution. 相似文献
160.
Impact of sourdough fermented with Lactobacillus plantarum FST 1.7 on baking and sensory properties of gluten-free breads 总被引:1,自引:0,他引:1
Anika Wolter Anna-Sophie Hager Emanuele Zannini Michael Czerny Elke K. Arendt 《European Food Research and Technology》2014,239(1):1-12
Sourdoughs were produced from buckwheat, oat, quinoa, sorghum, teff and wheat flour using the heterofermentative lactic acid bacteria Lactobacillus plantarum FST 1.7 and added to a basic bread formulation of flour from the same grain type (20 % addition level). Dough rheology, textural (crumb hardness, specific volume) and structural bread characteristics (crumb porosity, cell volume, brightness) of sourdough-containing breads were compared to non-sourdough-containing breads (control). Changes in protein profiles as analysed with capillary electrophoresis were observed in all sourdoughs. Furthermore, sourdough addition led to decreased dough strength resulting in softer dough. No influences on specific volume and hardness on day of baking were found for gluten-free sourdough breads. The staling rate was reduced in buckwheat (from 8 ± 2 to 6 ± 2 N/day) and teff sourdough bread (13 ± 1 to 10 ± 4 N/day), however, not significantly in comparison with the control breads. On the contrary, in wheat sourdough bread, the staling rate was significantly reduced (2 ± 1 N/day) in comparison with control bread (5 ± 1 N/day). Sourdough addition increased the cell volume significantly in sorghum (+61 %), teff (+92 %) and wheat sourdough breads (+78 %). Therefore, crumb porosity was significantly increased in all gluten-free and wheat sourdough breads. Shelf life for sourdough breads was one (teff and oat), two (buckwheat, quinoa and sorghum) and 3 days (wheat) and was not prolonged by sourdough addition. The inferior aroma of breads prepared from the gluten-free flours was also not improved by sourdough addition. 相似文献