Enhanced quantum teleportation in the background of Schwarzschild spacetime by weak measurements

It is commonly believed that the fidelity of quantum teleportation in the gravitational field would be degraded due to the heat up by the Hawking radiation. In this paper, we point out that the Hawking effect could be eliminated by the combined action of pre- and post-weak measurements, and thus the teleportation fidelity is almost completely protected. It is intriguing to notice that the enhancement of fidelity could not be attributed to the improvement of entanglement, but rather to the probabilistic nature of weak measurements. Our work extends the ability of weak measurements as a quantum technique to battle against gravitational decoherence in relativistic quantum information.Comment: 9 pages, 5 figures, comments are welcom

Functional linear regression analysis for longitudinal data

We propose nonparametric methods for functional linear regression which are designed for sparse longitudinal data, where both the predictor and response are functions of a covariate such as time. Predictor and response processes have smooth random trajectories, and the data consist of a small number of noisy repeated measurements made at irregular times for a sample of subjects. In longitudinal studies, the number of repeated measurements per subject is often small and may be modeled as a discrete random number and, accordingly, only a finite and asymptotically nonincreasing number of measurements are available for each subject or experimental unit. We propose a functional regression approach for this situation, using functional principal component analysis, where we estimate the functional principal component scores through conditional expectations. This allows the prediction of an unobserved response trajectory from sparse measurements of a predictor trajectory. The resulting technique is flexible and allows for different patterns regarding the timing of the measurements obtained for predictor and response trajectories. Asymptotic properties for a sample of $n$ subjects are investigated under mild conditions, as $n\to \infty$, and we obtain consistent estimation for the regression function. Besides convergence results for the components of functional linear regression, such as the regression parameter function, we construct asymptotic pointwise confidence bands for the predicted trajectories. A functional coefficient of determination as a measure of the variance explained by the functional regression model is introduced, extending the standard $R^2$ to the functional case. The proposed methods are illustrated with a simulation study, longitudinal primary biliary liver cirrhosis data and an analysis of the longitudinal relationship between blood pressure and body mass index.Comment: Published at http://dx.doi.org/10.1214/009053605000000660 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Enhancing teleportation of quantum Fisher information by partial measurements

The purport of quantum teleportation is to completely transfer information from one party to another distant partner. However, from the perspective of parameter estimation, it is the information carried by a particular parameter, not the information of total quantum state that needs to be teleported. Due to the inevitable noise in environment, we propose two schemes to enhance quantum Fisher information (QFI) teleportation under amplitude damping noise with the technique of partial measurements. We find that post partial measurement can greatly enhance the teleported QFI, while the combination of prior partial measurement and post partial measurement reversal could completely eliminate the effect of decoherence. We show that, somewhat consequentially, enhancing QFI teleportation is more economic than that of improving fidelity teleportation. Our work extends the ability of partial measurements as a quantum technique to battle decoherence in quantum information processing.Comment: Revised version, minor changes, accepted by Phys. Rev.

Protecting entanglement from correlated amplitude damping channel using weak measurement and quantum measurement reversal

Based on the quantum technique of weak measurement, we propose a scheme to protect the entanglement from correlated amplitude damping decoherence. In contrast to the results of memoryless amplitude damping channel, we show that the memory effects play a significant role in the suppression of entanglement sudden death and protection of entanglement under severe decoherence. Moreover, we find that the initial entanglement could be drastically amplified by the combination of weak measurement and quantum measurement reversal even under the correlated amplitude damping channel. The underlying mechanism can be attributed to the probabilistic nature of weak measurements.Comment: 11 pages, 5 figures, accepted by Quantum Information Processin

A STUDY OF METACOGNITIVE STRATEGIES UTILIZED IN READING AND LISTENING COMPREHENSION: AN INVESTIGATION OF NURSING JUNIOR COLLEGE ENGLISH LEARNERS

The purpose of this study was to analyze English-learners’ metacognition when engaged in reading and listening tasks, to determine if there was a correlation between their reading metacognition and listening metacognition, and to determine if metacognition levels differed between students of basic, intermediate, and advanced English levels. One class of 50 nursing students in a 5-year nursing program was assigned to participate in this study for one semester. The learners were divided into three groups (high, intermediate, and low) based on their score on an English listening test. At the beginning of the semester, they listened to a lesson called “Dangerous Dining.” Five months later, the students were presented with the same lesson, though this time in written form rather than spoken form, and their reading comprehension was tested using the same questions. Then the learners were asked to fill out two online questionnaires: a 21-question questionnaire about their reading strategies, and a 30-question questionnaire about their listening strategies. The surveys were designed to gauge the participants’ metacognitive awareness. The results showed that there was a positive and strong significant correlation between the learners’ listening metacognitive strategy and reading metacognitive strategy, r=0. 775, p<0.01. With regard to the first factor (Global Reading Strategies) for high-level learners there was a positive and strong significant correlation between listening and reading strategies, r=1, p<0.01, but there was no significant correlation between the second factor (Problem-Solving Strategies) and the third factor (Support reading Strategies). As to the first factor (Global Reading Strategies) and the third factor (Support Reading Strategies) for intermediate-level learners, there was no significant correlation between listening and reading strategies, but there was a significant correlation to the second factor (Problem-Solving Strategies), r=0. 656, p<0.05. As regards the first factor (Global Reading Strategies), the second factor (Problem-Solving Strategies) and the third factor (Support Reading Strategies) for low-level learners, there was a significant correlation between listening and reading strategies, r=0. 73, p<0.01, r=0. 67, p<0.01, r=0. 44, p>0.01, respectively. The results revealed that there was a positive significant correlation between reading comprehension and listening comprehension for low-level learners. The intermediate and advanced language learners reported applying fewer listening metacognitive strategies to reading metacognitive strategies than the low-level language learners because they had internalized the listening/reading metacognitive strategies to experience them automatically and didn’t report the automated process. They thus used fewer metacognitive strategies.  Article visualizations

Hyperlinks with multiple destinations

Conventional hyperlinks have a single destination. This disclosure describes hyperlinks with multiple hyperlink destinations and a corresponding user interface that enables users to create such hyperlinks

Charm of Nuo—Nuo Opera “Dongdongtui” of Dong Minority

“Dongdongtui”, a kind of original sacrificial Nuo opera, was included in the first batch of national intangible cultural heritage protection list in 2006. It only exists in Tianjing village, Xinhuang Dong autonomous county, Hunan province. Previously, the researchers only focused on the study of the intangible cultural heritage value of “Dongdongtui” and the exploration of its inheritance and development. However, due to the internal and external resistance, the government has not achieved good results in the implementation of the action, and the people with insight are unable to protect it. The national inheritor is 90 years old. His disciples are not capable enough to take up the mantle. There are few new students, and the influence of “Dongdongtui” is very limited in the region. “Dongdongtui” is spiritually lack of attraction, penetration, social acceptance and so on. It is facing with a dilemma of inheritance and development. Based on these, we went to the village and got close to “Dongdongtui”, personally felt the charm of masks, costumes and performances, and inquired about its value. Finally, combining with local geography, culture and tourism resources, we tried to propose a new region-wide tourism strategy which is suitable for the development of “Dongdongtui”