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71.
72.
Image morphing, or image interpolation in the time domain, deals with the metamorphosis of one image into another. In this paper, a new class of image morphing algorithms is proposed based on the theory of optimal mass transport. The L(2) mass moving energy functional is modified by adding an intensity penalizing term, in order to reduce the undesired double exposure effect. It is an intensity-based approach and, thus, is parameter free. The optimal warping function is computed using an iterative gradient descent approach. This proposed morphing method is also extended to doubly connected domains using a harmonic parameterization technique, along with finite-element methods.  相似文献   
73.
Cross-phase modulation in multispan WDM optical fiber systems   总被引:4,自引:0,他引:4  
The spectral characteristics of cross-phase modulation (XPM) in multispan intensity-modulation direct-detection (IM-DD) optical systems are investigated, both experimentally and theoretically. XPM crosstalk levels and its spectral features are found to be strongly dependent on fiber dispersion and optical signal channel spacing. Interference between XPM-induced crosstalk effects created in different amplified fiber spans is also found to be important to determine the overall frequency response of XPM crosstalk effects. XPM crosstalk between channels with different data rates is evaluated. The crosstalk level between higher and lower bit rate channels is found to be similar to that between two lower bit rate channels. The effect of dispersion compensation on XPM crosstalk in multispan optical systems is discussed and per span dispersion compensation was found to be the most effective way to minimize the effect of XPM crosstalk  相似文献   
74.
A geometrically nonlinear, simply supported beam under the influence of time-dependent external forcing serves as a testbed to demonstrate application of the optimal spatiotemporal reduced order modeling (OPSTROM) framework proposed in Part I of this work. Fully resolved simulations, which are relatively expensive to perform, are used to accurately predict the beam response for a few forcing parameters. More affordable simulations are achieved with a conventional finite-difference scheme by coarsening the computational grid in space and time. Discretization errors are reduced with OPSTROM as subgrid-scale models are designed to account for the underlying space-time statistical structure using principles of mean-square error minimization, conditional expectations and stochastic estimation. When included in the under-resolved simulations, these optimal subgrid-scale models are shown to significantly improve the accuracy of predictions for both periodic and chaotic response types. This improved accuracy is further demonstrated through a set of numerical experiments designed to capture the complex bifurcation behavior of the beam response.  相似文献   
75.
Allen  David E.  McAleer  Michael 《Scientometrics》2022,127(3):1643-1655
Scientometrics - The paper features an analysis of former President Trump’s early tweets on COVID-19 in the context of Dr. Fauci’s recently revealed email trove. The tweets are analysed...  相似文献   
76.
Engineering synthetic interfaces between membranes has potential applications in designing non-native cellular communication pathways and creating synthetic tissues. Here, InterSpy is introduced as a synthetic biology tool consisting of a heterodimeric protein engineered to form and maintain membrane–membrane interfaces between apposing synthetic as well as cell membranes through the SpyTag/SpyCatcher interaction. The inclusion of split fluorescent protein fragments in InterSpy allows tracking of the formation of a membrane–membrane interface and reconstitution of functional fluorescent protein in the space between apposing membranes. First, InterSpy is demonstrated by testing split protein designs using a mammalian cell-free expression (CFE) system. By utilizing co-translational helix insertion, cell-free synthesized InterSpy fragments are incorporated into the membrane of liposomes and supported lipid bilayers with the desired topology. Functional reconstitution of split fluorescent protein between the membranes is strictly dependent on SpyTag/SpyCatcher. Finally, InterSpy is demonstrated in mammalian cells by detecting fluorescence reconstitution of split protein at the membrane–membrane interface between two cells each expressing a component of InterSpy. InterSpy demonstrates the power of CFE systems in the functional reconstitution of synthetic membrane interfaces via proximity-inducing proteins. This technology may also prove useful where cell-cell contacts and communication are recreated in a controlled manner using minimal components.  相似文献   
77.
The objective of this study was to evaluate the effects of diet starch concentration and fermentability (SF) fed during the early postpartum (PP) period on dry matter intake (DMI), yields of milk and milk components, body reserves, and metabolism. Fifty-two multiparous Holstein cows were used in a randomized block design with a 2 × 2 factorial arrangement of treatments. Treatment diets were formulated to 22% (LS) or 28% (HS) starch with dry ground corn (DGC) or high-moisture corn (HMC) as the primary starch source. Treatments were fed from 1 to 23 d PP and cows were switched to a common diet until 72 d PP to measure carryover (CO) effects. Treatment period (TP) diets were formulated for 22% forage neutral detergent fiber and 17% crude protein, and starch concentration was adjusted by substitution of corn grain for soyhulls. Throughout the experiment DMI and milk yield were measured daily, and milk components, body condition score (BCS), and body weight were measured weekly. Blood was collected weekly during the TP and every second week during the CO period. During the TP, HMC decreased DMI more when included in the HS (3.9 kg/d) than in the LS (0.9 kg/d) diets and HMC decreased yields of milk, fat, and FCM by 4.3, 0.19, and 4.8 kg/d, respectively. Treatments also interacted over time to decrease DMI and yields of milk and milk components more for HMC compared with DGC as time progressed during the TP. Loss of BCS was increased when HMC was fed in a HS diet (?0.38 vs. ?0.17) and decreased when included in a LS diet (?0.21 vs. ?0.29) with no effects on body weight change during the TP. Treatments interacted with time to affect plasma concentrations of glucose and insulin with HS increasing concentrations early in the TP compared with LS but with similar effects by the end of the TP. During the CO period, treatment effects on DMI diminished over time with no main effects of treatment for the entire period. Starch concentration and SF interacted to affect yields of milk, fat, and FCM during the CO period, which were greater for HS-DGC and LS-HMC (54.8 and 52.8, 1.76 and 1.81, and 51.3 and 52.2 kg/d, respectively) than for LS-DGC and HS-HMC (51.2 and 51.0, 1.68 and 1.64, and 48.4 and 48.6 kg/d, respectively). Treatments did not affect BCS change during the CO period but HS lost body weight compared with LS (?5.7 vs. 7.0 kg). Blood glucose and insulin concentrations were not affected by treatments during the CO period. Feeding a highly fermentable starch source during the early PP period decreased DMI and yields of milk and milk components compared with a less fermentable starch source and the depression in DMI was greater when fed in the higher starch diet. However, diet starch concentration had no effects on yield of milk or milk components.  相似文献   
78.
Kirsty E. Allen  Brent Murray 《LWT》2006,39(3):225-234
Aeration properties of acidified casein-stabilized emulsions containing liquid oil droplets have been compared to the whipping of dairy cream. The foam systems were characterized in terms of overrun, microstructure, drainage stability, and rheology. With acidification using glucono-δ-lactone, the casein-stabilized emulsions could be aerated to give foams of far higher overrun (>600%) than whipped cream (∼120%). The development of foam volume, stability and rheology in the aerated casein-stabilized emulsion systems was found to be strongly dependent on the pH and the concentration of added calcium ions. Whereas whipped cream is stabilized by partially coalesced fat globules, the casein emulsion foams are stabilized by aggregation (gelation) of the protein coat surrounding the oil droplets. Casein emulsion foams formed at low pH were found to be more stable than whipped cream, whilst those formed at high pH were predominantly liquid-like and unstable. Instability arose in the acidified casein emulsion foams mainly through gel syneresis. We conclude that there are substantial textural differences between whipped cream and acidified casein emulsion foams, especially in terms of the small-deformation rheology and the extent of the linear viscoelastic regime.  相似文献   
79.
Effects of the digestibility of neutral detergent fiber (NDF) from forage on performance of dairy cows were evaluated statistically using treatment means for 13 sets of forage comparisons reported in the literature. All comparisons reported significant differences in NDF digestibilities of forages in situ or in vitro. Treatment means were blocked by study or by additional factorial treatment within a study to remove variation among experiments. The statistical model included random effect of block, fixed factorial effect of NDF digestibility (high or low), and dietary NDF concentration as a covariate. Enhanced NDF digestibility of forage significantly increased dry matter intake (DMI) and milk yield. A one-unit increase in NDF digestibility in vitro or in situ was associated with a 0.17-kg increase in DMI and a 0.25-kg increase in 4% fat-corrected milk. Differences in NDF digestibility between treatments were greater when measured in vitro or in situ than when measured in vivo. Digestibility of NDF in vitro or in situ might be a better indicator of DMI than NDF digestibility in vivo because forages with high in vitro or in situ NDF digestibilities might have shorter rumen retention times, allowing greater DMI at the expense of NDF digestibility in vivo. Digestibility of NDF is an important parameter of forage quality.  相似文献   
80.
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