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Sample records for distance decoy state

  1. Long distance decoy state quantum key distribution in optical fiber

    CERN Document Server

    Rosenberg, D; Hiskett, P A; Hughes, R J; Lita, A E; Nam, S W; Nordholt, J E; Peterson, C G; Rice, P R; Harrington, Jim W.; Hiskett, Philip A.; Hughes, Richard J.; Lita, Adriana E.; Nam, Sae Woo; Nordholt, Jane E.; Peterson, Charles G.; Rice, Patrick R.; Rosenberg, Danna

    2006-01-01

    The theoretical existence of photon-number-splitting attacks creates a security loophole for most quantum key distribution (QKD) demonstrations that use a highly attenuated laser source. Using ultra-low-noise, high-efficiency transition-edge sensor photo-detectors, we have implemented the first finite statistics version of a decoy state protocol in a one-way QKD system, enabling the creation of secure keys immune to both photon-number-splitting attacks and Trojan horse attacks over 107 km of optical fiber.

  2. Decoy State Quantum Key Distribution

    Science.gov (United States)

    Lo, Hoi-Kwong

    2005-10-01

    Quantum key distribution (QKD) allows two parties to communicate in absolute security based on the fundamental laws of physics. Up till now, it is widely believed that unconditionally secure QKD based on standard Bennett-Brassard (BB84) protocol is limited in both key generation rate and distance because of imperfect devices. Here, we solve these two problems directly by presenting new protocols that are feasible with only current technology. Surprisingly, our new protocols can make fiber-based QKD unconditionally secure at distances over 100km (for some experiments, such as GYS) and increase the key generation rate from O(η2) in prior art to O(η) where η is the overall transmittance. Our method is to develop the decoy state idea (first proposed by W.-Y. Hwang in "Quantum Key Distribution with High Loss: Toward Global Secure Communication", Phys. Rev. Lett. 91, 057901 (2003)) and consider simple extensions of the BB84 protocol. This part of work is published in "Decoy State Quantum Key Distribution", . We present a general theory of the decoy state protocol and propose a decoy method based on only one signal state and two decoy states. We perform optimization on the choice of intensities of the signal state and the two decoy states. Our result shows that a decoy state protocol with only two types of decoy states--a vacuum and a weak decoy state--asymptotically approaches the theoretical limit of the most general type of decoy state protocols (with an infinite number of decoy states). We also present a one-decoy-state protocol as a special case of Vacuum+Weak decoy method. Moreover, we provide estimations on the effects of statistical fluctuations and suggest that, even for long distance (larger than 100km) QKD, our two-decoy-state protocol can be implemented with only a few hours of experimental data. In conclusion, decoy state quantum key distribution is highly practical. This part of work is published in "Practical Decoy State for Quantum Key Distribution

  3. Experimental long-distance decoy-state quantum key distribution based on polarization encoding.

    Science.gov (United States)

    Peng, Cheng-Zhi; Zhang, Jun; Yang, Dong; Gao, Wei-Bo; Ma, Huai-Xin; Yin, Hao; Zeng, He-Ping; Yang, Tao; Wang, Xiang-Bin; Pan, Jian-Wei

    2007-01-05

    We demonstrate the decoy-state quantum key distribution (QKD) with one-way quantum communication in polarization space over 102 km. Further, we simplify the experimental setup and use only one detector to implement the one-way decoy-state QKD over 75 km, with the advantage to overcome the security loopholes due to the efficiency mismatch of detectors. Our experimental implementation can really offer the unconditionally secure final keys. We use 3 different intensities of 0, 0.2, and 0.6 for the light sources in our experiment. In order to eliminate the influences of polarization mode dispersion in the long-distance single-mode optical fiber, an automatic polarization compensation system is utilized to implement the active compensation.

  4. Experimental Long-Distance Decoy-State Quantum Key Distribution Based On Polarization Encoding

    CERN Document Server

    Peng, C Z; Ma, H X; Pan, J W; Wang, X B; Yang, D; Yang, T; Yin, H; Zeng, H P; Zhang, J; Gao, Wei-Bo; Ma, Huai-Xin; Pan, Jian-Wei; Peng, Cheng-Zhi; Wang, Xiang-Bin; Yang, Dong; Yang, Tao; Yin, Hao; Zeng, He-Ping; Zhang, Jun

    2006-01-01

    We demonstrate the decoy-state quantum key distribution (QKD) with one-way quantum communication in polarization space over 75 km. So far, our experimental implementation is the only one that really offers the unconditionally secure final keys among all the implementations of long-distance QKD with weak coherent states. We use 3 different intensities of 0, 0.2 and 0.6 for the pulses of source in our experiment. In order to eliminate the influences of polarization mode dispersion in the long-distance single-mode optical fiber, an automatic polarization compensation system is utilized to implement the active compensation. Only one detector is used in our experiment. The secure distance can be raised to 120 km given 4 detectors.

  5. Decoy State Quantum Key Distribution with Odd Coherent State

    Institute of Scientific and Technical Information of China (English)

    SUN Shi-Hai; GAO Ming; DAI Hong-Yi; CHEN Ping-Xing; LI Cheng-Zu

    2008-01-01

    We propose a decoy state quantum key distribution scheme with odd coherent state which follows sub-Poissonian distributed photon count and has low probability of the multi-photon event and vacuum event in each pulse. The numerical calculations show that our scheme can improve efficiently the key generation rate and secure communication distance. Furthermore, only one decoy state is necessary to approach to the perfect asymptotic limit with infinite decoy states in our scheme, but at least two decoy states are needed in other scheme.

  6. Quantum Key Distribution Using Decoy State Protocol

    Directory of Open Access Journals (Sweden)

    Sellami Ali

    2009-01-01

    Full Text Available Problem statement: Quantum key distribution provides unconditional security guaranteed by the fundamental laws of quantum physics. Unfortunately, for real-life experimental set-ups, which mainly based on faint laser pulses, the occasional production of multi-photons and channel loss make it possible for sophisticated eavesdroppers to launch various subtle eavesdropping attacks including the Photon Number Splitting (PNS attack. The decoy state protocols recently proposed to beat PNS attack and to improve dramatically distance and secure key generation rate of Quantum Key Distribution (QKD. Approach: Objective of this study was experimental implementation of weak decoy + vacuum states QKD for increasing the performance of QKD system. To show conceptually how simple it was to apply the weak decoy + vacuum state idea to a commercial QKD system, we chosen ID-3000 commercial quantum key distribution system manufactured by id quantique. To implement the weak decoy + vacuum state protocol, we had to add some new optical and electronics components to id quantique and to attenuate each signal to the intensity of either signal state or weak decoy or vacuum state randomly. Results: In our implementation, the attenuation will be done by placing a VOA (variable optical attenuator in Alice’s side. Specifically, our QKD system required the polarizations of 2 pulses from the same signal to be orthogonal. Therefore the VOA must be polarization independent so as to attenuate the two pulses equally. The VOA utilized in experiment to attenuate signals dynamically was Intensity Modulator (IM. We had implemented weak + vacuum protocol on a modified commercial QKD system over a 25 km of telecom fibers with an unconditionally secure key rate of 6.2931x10-4 per pulse. Conclusion: By making simple modifications to a commercial quantum key distribution system, we could achieve much better performance with substantially higher key generation rate and longer distance than

  7. Decoy States and Two Way Quantum Key Distribution Schemes

    CERN Document Server

    Shaari, J S; Ali, Sellami

    2010-01-01

    We study the possible application of the decoy state method on a basic two way quantum key distribution (QKD) scheme to extend its distance. Noting the obvious advantage of such a QKD scheme in allowing for single as well as double photon contributions, we derive relevant lower-bounds on the corresponding gains in a practical decoy state implementation using two intensities for decoy states. We work with two different approaches in this vein and compare these with an ideal infinite decoy state case as well as the simulation of the original LM05.

  8. Decoy State Quantum Key Distribution: Theory and Practice

    Science.gov (United States)

    Zhao, Yi; Lo, Hoi-Kwong; Ma, Xiongfeng; Qi, Bing; Chen, Kai; Qian, Li

    2007-03-01

    Decoy state quantum key distribution (QKD) has been proposed as a novel approach to improve dramatically both the security and the performance of practical QKD set-ups. We proved its security, and proposed the first practical decoy state QKD protocols, including the one-decoy protocol, the weak+vacuum protocol, and the general two-decoy protocol. Our further study shows that the two-way communication can effectively improve the performance of decoy state QKD. We performed the first experiments of decoy state QKD. Two protocols -- the one-decoy protocol and the weak+vacuum protocol -- were implemented with a maximum transmission distance of 60km. We implemented the decoy state method by adding commercial acousto-optic modulator to a commercial QKD system. Our theoretical and experimental studies show explicitly the power and the feasibility of decoy method, and brings it to our real- life. Our works are published in [1-5]. [1] H. -K. Lo, X. Ma, and K. Chen, Phys. Rev. Lett. 94 230504 (2005) [2] X. Ma et. al., Phys. Rev. A 72, 012326 (2005) [3] Y. Zhao et. al., Phys. Rev. Lett., 96, 070502 (2006) [4] Y. Zhao et. al., in Proceedings of IEEE ISIT (IEEE, 2006) pp. 2094-2098 [5] X. Ma et. al., Phys. Rev. A 74, 032330 (2006)

  9. Numerical analysis of decoy state quantum key distribution protocols

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, Jim W [Los Alamos National Laboratory; Rice, Patrick R [Los Alamos National Laboratory

    2008-01-01

    Decoy state protocols are a useful tool for many quantum key distribution systems implemented with weak coherent pulses, allowing significantly better secret bit rates and longer maximum distances. In this paper we present a method to numerically find optimal three-level protocols, and we examine how the secret bit rate and the optimized parameters are dependent on various system properties, such as session length, transmission loss, and visibility. Additionally, we show how to modify the decoy state analysis to handle partially distinguishable decoy states as well as uncertainty in the prepared intensities.

  10. Practical non-orthogonal decoy state quantum key distribution with heralded single photon source

    Institute of Scientific and Technical Information of China (English)

    Mi Jing-Long; Wang Fa-Qiang; Lin Qing-Qun; Liang Rui-Sheng

    2008-01-01

    Recently the performance of the quantum key distribution (QKD) is substantially improved by the decoy state method and the non-orthogonal encoding protocol, separately. In this paper, a practical non-orthogonal decoy state protocol with a heralded single photon source (HSPS) for QKD is presented. The protocol is based on 4 states with different intensities, i.e. one signal state and three decoy states. The signal state is for generating keys; the decoy states arc for detecting the eavesdropping and estimating the fraction of single-photon and two-photon pulses. We have discussed three cases of this protocol, i.e. the general case, the optimal case and the special case. Moreover, the final key rate over transmission distance is simulated. For the low dark count of the HSPS and the utilization of the two-photon pulses, our protocol has a higher key rate and a longer transmission distance than any other decoy state protocol.

  11. Experimental passive decoy-state quantum key distribution

    Science.gov (United States)

    Sun, Qi-Chao; Wang, Wei-Long; Liu, Yang; Zhou, Fei; Pelc, Jason S.; Fejer, M. M.; Peng, Cheng-Zhi; Chen, Xianfeng; Ma, Xiongfeng; Zhang, Qiang; Pan, Jian-Wei

    2014-08-01

    The decoy-state method is widely used in practical quantum key distribution systems to replace ideal single photon sources with realistic light sources of varying intensities. Instead of active modulation, the passive decoy-state method employs built-in decoy states in a parametric down-conversion photon source, which can decrease the side channel information leakage in decoy-state preparation and hence increase the security. By employing low dark count up-conversion single photon detectors, we experimentally demonstrate the passive decoy-state method over a 50 km long optical fiber and obtain a key rate of about 100 bit s-1. Our result suggests that the passive decoy-state source is a practical candidate for future quantum communication implementation.

  12. New passive decoy-state quantum key distribution with thermal distributed parametric down-conversion source

    Science.gov (United States)

    Wei, Jie; Zhang, Chun-Hui; Wang, Qin

    2017-02-01

    We present a new scheme on implementing the passive quantum key distribution with thermal distributed parametric down-conversion source. In this scheme, only one-intensity decoy state is employed, but we can achieve very precise estimation on the single-photon-pulse contribution by utilizing those built-in decoy states. Moreover, we compare the new scheme with other practical methods, i.e., the standard three-intensity decoy-state BB84 protocol using either weak coherent states or parametric down-conversion source. Through numerical simulations, we demonstrate that our new scheme can drastically improve both the secure transmission distance and the key generation rate.

  13. General Theory of Decoy-State Quantum Cryptography with Dark Count Rate Fluctuation

    Institute of Scientific and Technical Information of China (English)

    GAO Xiang; SUN Shi-Hai; LIANG Lin-Mei

    2009-01-01

    The existing theory of decoy-state quantum cryptography assumes that the dark count rate is a constant, but in practice there exists fluctuation. We develop a new scheme of the decoy state, achieve a more practical key generation rate in the presence of fluctuation of the dark count rate, and compare the result with the result of the decoy-state without fluctuation.It is found that the key generation rate and maximal secure distance will be decreased under the influence of the fluctuation of the dark count rate.

  14. Practical issues in decoy-state quantum key distribution based on the central limit theorem

    Science.gov (United States)

    Trushechkin, A. S.; Kiktenko, E. O.; Fedorov, A. K.

    2017-08-01

    Decoy-state quantum key distribution (QKD) is a standard tool for long-distance quantum communications. An important issue in this field is processing the decoy-state statistics taking into account statistical fluctuations (or "finite-key effects"). In this work, we propose and analyze an option for decoy statistics processing, which is based on the central limit theorem. We discuss such practical issues as inclusion of the failure probability of the decoy-state statistical estimates in the total failure probability of a QKD protocol and also taking into account the deviations of the binomially distributed random variables used in the estimations from the Gaussian distribution. The results of numerical simulations show that the obtained estimations are quite tight. The proposed technique can be used as a part of post-processing procedures for industrial quantum key distribution systems.

  15. Parameter optimization in biased decoy-state quantum key distribution with both source errors and statistical fluctuations

    Science.gov (United States)

    Zhu, Jian-Rong; Li, Jian; Zhang, Chun-Mei; Wang, Qin

    2017-10-01

    The decoy-state method has been widely used in commercial quantum key distribution (QKD) systems. In view of the practical decoy-state QKD with both source errors and statistical fluctuations, we propose a universal model of full parameter optimization in biased decoy-state QKD with phase-randomized sources. Besides, we adopt this model to carry out simulations of two widely used sources: weak coherent source (WCS) and heralded single-photon source (HSPS). Results show that full parameter optimization can significantly improve not only the secure transmission distance but also the final key generation rate. And when taking source errors and statistical fluctuations into account, the performance of decoy-state QKD using HSPS suffered less than that of decoy-state QKD using WCS.

  16. Nonorthogonal Decoy-State Quantum Key Distribution

    Institute of Scientific and Technical Information of China (English)

    LI Jing-Bo; FANG Xi-Ming

    2006-01-01

    @@ In practical quantum key distribution (QKD), weak coherent states as the photon source have a limit in the secure key rate and transmission distance because of the existence of multi-photon pulses and heavy loss in transmission line.

  17. An enhanced proposal on decoy-state measurement device-independent quantum key distribution

    Science.gov (United States)

    Wang, Qin; Zhang, Chun-Hui; Luo, Shunlong; Guo, Guang-Can

    2016-09-01

    By employing pulses involving three-intensity, we propose a scheme for the measurement device-independent quantum key distribution with heralded single-photon sources. We make a comparative study of this scheme with the standard three-intensity decoy-state scheme using weak coherent sources or heralded single-photon sources. The advantage of this scheme is illustrated through numerical simulations: It can approach very closely the asymptotic case of using an infinite number of decoy-states and exhibits excellent behavior in both the secure transmission distance and the final key generation rate.

  18. Experimental demonstration of passive decoy state quantum key distribution

    Institute of Scientific and Technical Information of China (English)

    Zhang Yang; Wang Shuang; Yin Zhen-Qiang; Chen Wei; Liang Wen-Ye; Li Hong-Wei; Guo Guang-Can; Han Zheng-Fu

    2012-01-01

    Passive decoy state quantum key distribution (PDS-QKD) has advantages in high-speed scenarios.We propose a modified model to simulate the PDS-QKD with a weak coherent light source based on Curty's theory [Opt.Lett.343238 (2009)].The modified model can provide better performance in a practical PDS-QKD system.Moreover,we report an experimental demonstration of the PDS-QKD of over 22.0-dB channel loss.

  19. Simulation and Implementation of Decoy State Quantum Key Distribution over 60km Telecom Fiber

    CERN Document Server

    Zhao, Y; Ma, X; Qi, B; Qian, L; Lo, Hoi-Kwong; Ma, Xiongfeng; Qi, Bing; Qian, Li; Zhao, Yi

    2006-01-01

    Decoy state quantum key distribution (QKD) has been proposed as a novel approach to improve dramatically both the security and the performance of practical QKD set-ups. Recently, many theoretical efforts have been made on this topic and have theoretically predicted the high performance of decoy method. However, the gap between theory and experiment remains open. In this paper, we report the first experiments on decoy state QKD, thus bridging the gap. Two protocols of decoy state QKD are implemented: one-decoy protocol over 15km of standard telecom fiber, and weak+vacuum protocol over 60km of standard telecom fiber. We implemented the decoy state method on a modified commercial QKD system. The modification we made is simply adding commercial acousto-optic modulator (AOM) on the QKD system. The AOM is used to modulate the intensity of each signal individually, thus implementing the decoy state method. As an important part of implementation, numerical simulation of our set-up is also performed. The simulation sh...

  20. Passive decoy-state quantum key distribution using weak coherent pulses with modulator attenuation

    Institute of Scientific and Technical Information of China (English)

    李源; 鲍皖苏; 李宏伟; 周淳; 汪洋

    2015-01-01

    Passive decoy-state quantum key distribution is more desirable than the active one in some scenarios. It is also affected by the imperfections of the devices. In this paper, the influence of modulator attenuation on the passive decoy-state method is considered. We introduce and analyze the unbalanced Mach–Zehnder interferometer, briefly, and combining with the virtual source and imaginary unitary transformation, we characterize the passive decoy-state method using a weak coherent photon source with modulator attenuation. According to the attenuation parameterδ, the pass efficiencies are given. Then, the key generation rate can be acquired. From numerical simulations, it can be seen that modulator attenuation has a non-negligible influence on the performance of passive-state QKD protocol. Based on the research, the analysis method of virtual source and imaginary unitary transformation are preferred in analyzing passive decoy state protocol, and the passive decoy-state method is better than the active one and is close to the active vacuum+weak decoy state under the condition of having the same modulator attenuation.

  1. Passive decoy-state quantum key distribution using weak coherent pulses with modulator attenuation

    Science.gov (United States)

    Li, Yuan; Bao, Wan-Su; Li, Hong-Wei; Zhou, Chun; Wang, Yang

    2015-11-01

    Passive decoy-state quantum key distribution is more desirable than the active one in some scenarios. It is also affected by the imperfections of the devices. In this paper, the influence of modulator attenuation on the passive decoy-state method is considered. We introduce and analyze the unbalanced Mach-Zehnder interferometer, briefly, and combining with the virtual source and imaginary unitary transformation, we characterize the passive decoy-state method using a weak coherent photon source with modulator attenuation. According to the attenuation parameter δ, the pass efficiencies are given. Then, the key generation rate can be acquired. From numerical simulations, it can be seen that modulator attenuation has a nonnegligible influence on the performance of passive-state QKD protocol. Based on the research, the analysis method of virtual source and imaginary unitary transformation are preferred in analyzing passive decoy state protocol, and the passive decoy-state method is better than the active one and is close to the active vacuum + weak decoy state under the condition of having the same modulator attenuation. Project supported by the National Natural Science Foundation of China (Grant No. 11304397).

  2. Three-intensity decoy-state method for measurement-device-independent quantum key distribution

    Science.gov (United States)

    Yu, Zong-Wen; Zhou, Yi-Heng; Wang, Xiang-Bin

    2013-12-01

    We study the measurement-device-independent quantum key distribution (MDI-QKD) in practice with limited resources, when there are only three different states in implementing the decoy-state method. We present a tighter explicit formula to estimate the lower bound of the yield of two-single-photon pulses sent by Alice and Bob. Moreover, we show that the bounding of this yield and phase flip error of single-photon pulse pairs can be further improved by using other constraints which can be solved by a simple and explicit program. Our methods here can significantly improve the key rate and the secure distance of MDI-QKD with only three intensities.

  3. The enhanced measurement-device-independent quantum key distribution with two-intensity decoy states

    Science.gov (United States)

    Zhu, Jian-Rong; Zhu, Feng; Zhou, Xing-Yu; Wang, Qin

    2016-09-01

    We put forward a new scheme for implementing the measurement-device-independent quantum key distribution (QKD) with weak coherent source, while using only two different intensities. In the new scheme, we insert a beam splitter and a local detector at both Alice's and Bob's side, and then all the triggering and non-triggering signals could be employed to process parameter estimations, resulting in very precise estimations for the two-single-photon contributions. Besides, we compare its behavior with two other often used methods, i.e., the conventional standard three-intensity decoy-state measurement-device-independent QKD and the passive measurement-device-independent QKD. Through numerical simulations, we demonstrate that our new approach can exhibit outstanding characteristics not only in the secure transmission distance, but also in the final key generation rate.

  4. Experimental demonstration of passive-decoy-state quantum key distribution with two independent lasers

    Science.gov (United States)

    Sun, Shi-Hai; Tang, Guang-Zhao; Li, Chun-Yan; Liang, Lin-Mei

    2016-09-01

    The decoy-state method could effectively enhance the performance of quantum key distribution (QKD) with a practical phase randomized weak coherent source. Although active modulation of the source intensity is effective and has been implemented in many experiments, passive preparation of decoy states is also an important addition to the family of decoy-state QKD protocols. In this paper, following the theory of Curty et al. [Phys. Rev. A 81, 022310 (2010), 10.1103/PhysRevA.81.022310], we experimentally demonstrate the phase-encoding passive-decoy-state QKD with only linear optical setups and threshold single-photon detectors. In our experiment, two homemade independent pulsed lasers, with visibility of Hong-Ou-Mandel interference 0.53 (±0.003 ) , have been implemented and used to passively generate the different decoy states. Finally, a secret key rate of 1.5 ×10-5 /pulse is obtained with 10-km commercial fiber between Alice and Bob.

  5. Round-robin differential-phase-shift quantum key distribution with a passive decoy state method

    Science.gov (United States)

    Liu, Li; Guo, Fen-Zhuo; Qin, Su-Juan; Wen, Qiao-Yan

    2017-02-01

    Recently, a new type of protocol named Round-robin differential-phase-shift quantum key distribution (RRDPS QKD) was proposed, where the security can be guaranteed without monitoring conventional signal disturbances. The active decoy state method can be used in this protocol to overcome the imperfections of the source. But, it may lead to side channel attacks and break the security of QKD systems. In this paper, we apply the passive decoy state method to the RRDPS QKD protocol. Not only can the more environment disturbance be tolerated, but in addition it can overcome side channel attacks on the sources. Importantly, we derive a new key generation rate formula for our RRDPS protocol using passive decoy states and enhance the key generation rate. We also compare the performance of our RRDPS QKD to that using the active decoy state method and the original RRDPS QKD without any decoy states. From numerical simulations, the performance improvement of the RRDPS QKD by our new method can be seen.

  6. Making the decoy-state measurement-device-independent quantum key distribution practically useful

    Science.gov (United States)

    Zhou, Yi-Heng; Yu, Zong-Wen; Wang, Xiang-Bin

    2016-04-01

    The relatively low key rate seems to be the major barrier to its practical use for the decoy-state measurement-device-independent quantum key distribution (MDI-QKD). We present a four-intensity protocol for the decoy-state MDI-QKD that hugely raises the key rate, especially in the case in which the total data size is not large. Also, calculations show that our method makes it possible for secure private communication with fresh keys generated from MDI-QKD with a delay time of only a few seconds.

  7. High-dimensional decoy-state quantum key distribution over multicore telecommunication fibers

    Science.gov (United States)

    Cañas, G.; Vera, N.; Cariñe, J.; González, P.; Cardenas, J.; Connolly, P. W. R.; Przysiezna, A.; Gómez, E. S.; Figueroa, M.; Vallone, G.; Villoresi, P.; da Silva, T. Ferreira; Xavier, G. B.; Lima, G.

    2017-08-01

    Multiplexing is a strategy to augment the transmission capacity of a communication system. It consists of combining multiple signals over the same data channel and it has been very successful in classical communications. However, the use of enhanced channels has only reached limited practicality in quantum communications (QC) as it requires the manipulation of quantum systems of higher dimensions. Considerable effort is being made towards QC using high-dimensional quantum systems encoded into the transverse momentum of single photons, but so far no approach has been proven to be fully compatible with the existing telecommunication fibers. Here we overcome such a challenge and demonstrate a secure high-dimensional decoy-state quantum key distribution session over a 300-m-long multicore optical fiber. The high-dimensional quantum states are defined in terms of the transverse core modes available for the photon transmission over the fiber, and theoretical analyses show that positive secret key rates can be achieved through metropolitan distances.

  8. A decoy-state protocol for quantum cryptography with 4 intensities of coherent states

    CERN Document Server

    Wang, X B

    2004-01-01

    In order to beat any type of photon-number-splitting attack, we In order to beat any type of photon-number-splitting attack, we propose a protocol for quantum key distributoin (QKD) using 4 different intensities of pulses. They are vacuum and coherent states with mean photon number $\\mu,\\mu'$ and $\\mu_s$. $\\mu_s$ is around 0.55 and this class of pulses are used as the main signal states. The other two classes of coherent states are used for both decoy and signal. We have shown that, given the typical set-up in practice, the key rate from the main signal pulses is more than 77% to 88% of the theoretically allowed maximal rate in the case of overall transmittance of $10^{-4}$ and $10^{-3}$.

  9. Field test of a practical secure communication network with decoy-state quantum cryptography.

    Science.gov (United States)

    Chen, Teng-Yun; Liang, Hao; Liu, Yang; Cai, Wen-Qi; Ju, Lei; Liu, Wei-Yue; Wang, Jian; Yin, Hao; Chen, Kai; Chen, Zeng-Bing; Peng, Cheng-Zhi; Pan, Jian-Wei

    2009-04-13

    We present a secure network communication system that operated with decoy-state quantum cryptography in a real-world application scenario. The full key exchange and application protocols were performed in real time among three nodes, in which two adjacent nodes were connected by approximate 20 km of commercial telecom optical fiber. The generated quantum keys were immediately employed and demonstrated for communication applications, including unbreakable real-time voice telephone between any two of the three communication nodes, or a broadcast from one node to the other two nodes by using one-time pad encryption.

  10. Finite-key analysis of a practical decoy-state high-dimensional quantum key distribution

    Science.gov (United States)

    Bao, Haize; Bao, Wansu; Wang, Yang; Zhou, Chun; Chen, Ruike

    2016-05-01

    Compared with two-level quantum key distribution (QKD), high-dimensional QKD enables two distant parties to share a secret key at a higher rate. We provide a finite-key security analysis for the recently proposed practical high-dimensional decoy-state QKD protocol based on time-energy entanglement. We employ two methods to estimate the statistical fluctuation of the postselection probability and give a tighter bound on the secure-key capacity. By numerical evaluation, we show the finite-key effect on the secure-key capacity in different conditions. Moreover, our approach could be used to optimize parameters in practical implementations of high-dimensional QKD.

  11. Hacking on decoy-state quantum key distribution system with partial phase randomization

    Science.gov (United States)

    Sun, Shi-Hai; Jiang, Mu-Sheng; Ma, Xiang-Chun; Li, Chun-Yan; Liang, Lin-Mei

    2014-04-01

    Quantum key distribution (QKD) provides means for unconditional secure key transmission between two distant parties. However, in practical implementations, it suffers from quantum hacking due to device imperfections. Here we propose a hybrid measurement attack, with only linear optics, homodyne detection, and single photon detection, to the widely used vacuum + weak decoy state QKD system when the phase of source is partially randomized. Our analysis shows that, in some parameter regimes, the proposed attack would result in an entanglement breaking channel but still be able to trick the legitimate users to believe they have transmitted secure keys. That is, the eavesdropper is able to steal all the key information without discovered by the users. Thus, our proposal reveals that partial phase randomization is not sufficient to guarantee the security of phase-encoding QKD systems with weak coherent states.

  12. Quantum Decoys

    CERN Document Server

    Arrighi, P

    2003-01-01

    Alice communicates with words drawn uniformly amongst $\\{\\ket{j}\\}_{j=1..n}$, the canonical orthonormal basis. Sometimes however Alice interleaves quantum decoys $\\{\\frac{\\ket{j}+i\\ket{k}}{\\sqrt{2}}\\}$ between her messages. Such pairwise superpositions of possible words cannot be distinguished from the message words. Thus as malevolent Eve observes the quantum channel, she runs the risk of damaging the superpositions (by causing a collapse). At the receiving end honest Bob, whom we assume is warned of the quantum decoys' distribution, checks upon their integrity with a measurement. The present work establishes, in the case of individual attacks, the tradeoff between Eve's information gain (her chances, if a message word was sent, of guessing which) and the disturbance she induces (Bob's chances, if a quantum decoy was sent, to detect tampering). Besides secure channel protocols, quantum decoys seem a powerful primitive for constructing n-dimensional quantum cryptographic applications. Moreover the methods emp...

  13. Free-space measurement-device-independent quantum-key-distribution protocol using decoy states with orbital angular momentum

    Science.gov (United States)

    Wang, Le; Zhao, Sheng-Mei; Gong, Long-Yan; Cheng, Wei-Wen

    2015-12-01

    In this paper, we propose a measurement-device-independent quantum-key-distribution (MDI-QKD) protocol using orbital angular momentum (OAM) in free space links, named the OAM-MDI-QKD protocol. In the proposed protocol, the OAM states of photons, instead of polarization states, are used as the information carriers to avoid the reference frame alignment, the decoy-state is adopted to overcome the security loophole caused by the weak coherent pulse source, and the high efficient OAM-sorter is adopted as the measurement tool for Charlie to obtain the output OAM state. Here, Charlie may be an untrusted third party. The results show that the authorized users, Alice and Bob, could distill a secret key with Charlie’s successful measurements, and the key generation performance is slightly better than that of the polarization-based MDI-QKD protocol in the two-dimensional OAM cases. Simultaneously, Alice and Bob can reduce the number of flipping the bits in the secure key distillation. It is indicated that a higher key generation rate performance could be obtained by a high dimensional OAM-MDI-QKD protocol because of the unlimited degree of freedom on OAM states. Moreover, the results show that the key generation rate and the transmission distance will decrease as the growth of the strength of atmospheric turbulence (AT) and the link attenuation. In addition, the decoy states used in the proposed protocol can get a considerable good performance without the need for an ideal source. Project supported by the National Natural Science Foundation of China (Grant Nos. 61271238 and 61475075), the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20123223110003), the Natural Science Research Foundation for Universities of Jiangsu Province of China (Grant No. 11KJA510002), the Open Research Fund of Key Laboratory of Broadband Wireless Communication and Sensor Network Technology, Ministry of Education, China (Grant No. NYKL2015011), and the

  14. Nonorthogonal decoy-state quantum key distribution based on coherent-state sup erp ositions%基于相干叠加态的非正交编码诱骗态量子密钥分发∗

    Institute of Scientific and Technical Information of China (English)

    孙伟; 尹华磊; 孙祥祥; 陈腾云

    2016-01-01

    非正交编码协议和诱骗态方法可以有效地抵御光子数分离攻击。由于相干叠加态中单光子成分高达90%,常作为单光子量子比特的替代出现,用于量子信息过程处理和计算。本文结合非正交编码协议和诱骗态方法提出一种新的量子密钥分发方案,光源采用相干叠加态,推导了单光子的密钥生成速率、计数率下限和误码率的上限,利用Matlab 模拟了无限多诱骗态情况下和有限多诱骗态情况下密钥生成速率和传输距离的关系,得出该方案可以提升密钥生成速率并且提高安全传输距离,验证了该方案可以进一步提高量子密钥分发系统的性能。%Nonorthogonal coded agreements and decoy state method can effectively protect the photon number against split-ting attack. Owing to the fact that the component of single-photon in the coherent-state superposition (CSS) is as high as 90%, CSS has recently emerged as an alternative to single-photon qubits for quantum information processing and metrology. The approximate CSS of small amplitudes is generated by the subtraction of photons from a squeezed vacuum state, and the approximate CSS of large amplitude is generated from Fock state by using a single homodyne detection. Here, we combine both of the methods and propose a new protocol by using the CSS as a light source. We derive the secure key generation rate, the lower bound of count rate and upper bound of error rate of single-photon. We simulate the curves relationship between secure key generation rate and safety transmission distance in the case of an infinite number of decoy states by using matlab. The parameters are given according to the Gobby-Yuan-Shields (GYS) experiment. We infer that the safety transmission distance achieves 147.4 km and the secure key generation rate is much higher than those of other schemes. We also simulate the relationship between key generation rate and safety transmission distance in

  15. Monge Distance between Quantum States

    CERN Document Server

    Zyczkowski, K; Zyczkowski, Karol; Slomczynski, Wojciech

    1998-01-01

    We define a metric in the space of quantum states taking the Monge distance between corresponding Husimi distributions (Q--functions). This quantity fulfills the axioms of a metric and satisfies the following semiclassical property: the distance between two coherent states is equal to the Euclidean distance between corresponding points in the classical phase space. We compute analytically distances between certain states (coherent, squeezed, Fock and thermal) and discuss a scheme for numerical computation of Monge distance for two arbitrary quantum states.

  16. The Monge distance between quantum states

    Energy Technology Data Exchange (ETDEWEB)

    Zyczkowski, Karol [Institute for Plasma Research, University of Maryland, College Park, MD (United States); Slomczynski, Wojciech [Instytut Matematyki, Uniwersytet Jagiellonski, Cracow (Poland)

    1998-11-13

    We define a metric in the space of quantum states taking the Monge distance between corresponding Husimi distributions (Q-functions). This quantity fulfils the axioms of a metric and satisfies the following semiclassical property: the distance between two coherent states is equal to the Euclidean distance between corresponding points in the classical phase space. We compute analytically distances between certain states (coherent, squeezed, Fock and thermal) and discuss a scheme for numerical computation of Monge distance for two arbitrary quantum states. (author)

  17. Improved protein structure selection using decoy-dependent discriminatory functions

    Directory of Open Access Journals (Sweden)

    Levitt Michael

    2004-06-01

    Full Text Available Abstract Background A key component in protein structure prediction is a scoring or discriminatory function that can distinguish near-native conformations from misfolded ones. Various types of scoring functions have been developed to accomplish this goal, but their performance is not adequate to solve the structure selection problem. In addition, there is poor correlation between the scores and the accuracy of the generated conformations. Results We present a simple and nonparametric formula to estimate the accuracy of predicted conformations (or decoys. This scoring function, called the density score function, evaluates decoy conformations by performing an all-against-all Cα RMSD (Root Mean Square Deviation calculation in a given decoy set. We tested the density score function on 83 decoy sets grouped by their generation methods (4state_reduced, fisa, fisa_casp3, lmds, lattice_ssfit, semfold and Rosetta. The density scores have correlations as high as 0.9 with the Cα RMSDs of the decoy conformations, measured relative to the experimental conformation for each decoy. We previously developed a residue-specific all-atom probability discriminatory function (RAPDF, which compiles statistics from a database of experimentally determined conformations, to aid in structure selection. Here, we present a decoy-dependent discriminatory function called self-RAPDF, where we compiled the atom-atom contact probabilities from all the conformations in a decoy set instead of using an ensemble of native conformations, with a weighting scheme based on the density scores. The self-RAPDF has a higher correlation with Cα RMSD than RAPDF for 76/83 decoy sets, and selects better near-native conformations for 62/83 decoy sets. Self-RAPDF may be useful not only for selecting near-native conformations from decoy sets, but also for fold simulations and protein structure refinement. Conclusions Both the density score and the self-RAPDF functions are decoy

  18. Novel High-Speed Polarization Source for Decoy-State BB84 Quantum Key Distribution over Free Space and Satellite Links

    CERN Document Server

    Yan, Zhizhong; Bourgoin, Jean-Philippe; Higgins, Brendon L; Gigov, Nikolay; MacDonald, Allison; Hübel, Hannes; Jennewein, Thomas

    2012-01-01

    To implement the BB84 decoy-state quantum key distribution (QKD) protocol over a lossy ground-satellite quantum uplink requires a source that has high repetition rate of short laser pulses, long term stability, and no phase correlations between pulses. We present a new type of telecom optical polarization and amplitude modulator, based on a balanced Mach-Zehnder interferometer configuration, coupled to a polarization-preserving sum-frequency generation (SFG) optical setup, generating 532 nm photons with modulated polarization and amplitude states. The weak coherent pulses produced by SFG meet the challenging requirements for long range QKD, featuring a high clock rate of 76 MHz, pico-second pulse width, phase randomization, and 98% polarization visibility for all states. Successful QKD has been demonstrated using this apparatus with full system stability up to 160 minutes and channel losses as high 57 dB [Phys. Rev. A, Vol. 84, p.062326]. We present the design and simulation of the hardware through the Muelle...

  19. Airborne target tracking algorithm against oppressive decoys in infrared imagery

    Science.gov (United States)

    Sun, Xiechang; Zhang, Tianxu

    2009-10-01

    This paper presents an approach for tracking airborne target against oppressive infrared decoys. Oppressive decoy lures infrared guided missile by its high infrared radiation. Traditional tracking algorithms have degraded stability even come to tracking failure when airborne target continuously throw out many decoys. The proposed approach first determines an adaptive tracking window. The center of the tracking window is set at a predicted target position which is computed based on uniform motion model. Different strategies are applied for determination of tracking window size according to target state. The image within tracking window is segmented and multi features of candidate targets are extracted. The most similar candidate target is associated to the tracking target by using a decision function, which calculates a weighted sum of normalized feature differences between two comparable targets. Integrated intensity ratio of association target and tracking target, and target centroid are examined to estimate target state in the presence of decoys. The tracking ability and robustness of proposed approach has been validated by processing available real-world and simulated infrared image sequences containing airborne targets and oppressive decoys.

  20. Decoys in Predation and Parasitism

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.

    2003-01-01

    Predator-prey or host-parasite dynamics can be altered by the presence of other species through several mechanisms. One such mechanism is the ‘‘decoy effect,’’ which itself can take a variety of forms. In its simplest form, the third species, which is inedible to the predator, nonetheless interferes

  1. Decoys in Predation and Parasitism

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.

    2003-01-01

    Predator-prey or host-parasite dynamics can be altered by the presence of other species through several mechanisms. One such mechanism is the ‘‘decoy effect,’’ which itself can take a variety of forms. In its simplest form, the third species, which is inedible to the predator, nonetheless interferes

  2. The Decoy Duck.

    Science.gov (United States)

    Ryan, Anna

    1997-01-01

    Describes the development processes of an instructional video for use in a course offered through the Extended Learning Institute of Northern Virginia Community College entitled Women Writers II. Characterizes the process of transforming this English course from a print-based to a distance-learning course as time-consuming, creative, and…

  3. Research on Partner-fly Infrared Decoys

    Institute of Scientific and Technical Information of China (English)

    HONG Yang; LI Yan-jun; WANG Qi

    2006-01-01

    With the rapid development of new generation of infrared-guided missiles, it is very difficult for the traditional point-source infrared decoys to confront them. Therefore it is important to research the jamming mechanism and tactical application of infrared decoys. Through the research on rocket-propelled infrared decoys, a movement model and a radiation pattern of partner-fly infrared decoy are established based on the jamming mechanism of infrared centroid effect, the aerodynamics principle as well as the aeronautical dynamics principle. A dynamic simulation seeking superiority is conducted for its firing range and direction, a tactical application method of partner-fly infrared decoy against infrared-guided missile is explored, and the technical conditions of partner-fly infrared decoys are determined.

  4. Evaluation of the State Authorization Processes for Distance Education

    Science.gov (United States)

    Ozdemir, Devrim; McDaniel, James

    2013-01-01

    In this article, the process of obtaining state authorizations for distance education at George Mason University is presented. The purpose of the paper is to provide guidance to those four-year public universities that deliver distance education programs. In order to attract students from multiple states, the U.S. Department of Education…

  5. Effect of noise on trace distance of remote state preparation

    Institute of Scientific and Technical Information of China (English)

    Chen Ai-Xi; Li Jia-Hua

    2005-01-01

    The influence of noise on the remote preparation of a qubit by an entangled pair is investigated. In Bloch sphere representation, we use the trace distance to describe how close the final state is to the original state to be prepared.Our studies include two cases. Firstly, we consider the sender and the receiver sharing a mixture of two Bell states as quantum channel in remote state preparation (RSP), and calculate the trace distance as a function of mixture ratio and angle of a state to be prepared. Secondly, the system-environment interaction is taken into account by including stochastic fluctuating terms in the system Hamiltonian. Solving the Bloch equations, we obtain the evolution density matrix of the system. We then apply this stochastic model to study the effect of noise on the trace distance of RSP.

  6. Going the Distance: Online Education in the United States, 2011

    Science.gov (United States)

    Allen, I. Elaine; Seaman, Jeff

    2011-01-01

    "Going the Distance: Online Education in the United States, 2011" is the ninth annual report on the state of online learning in U.S. higher education. The survey is designed, administered and analyzed by the Babson Survey Research Group. Data collection is conducted in partnership with the College Board. This year's study, like those for…

  7. Generation of distributed W-states over long distances

    Science.gov (United States)

    Li, Yi

    2017-08-01

    Ultra-secure quantum communication between distant locations requires distributed entangled states between nodes. Various methodologies have been proposed to tackle this technological challenge, of which the so-called DLCZ protocol is the most promising and widely adopted scheme. This paper aims to extend this well-known protocol to a multi-node setting where the entangled W-state is generated between nodes over long distances. The generation of multipartite W-states is the foundation of quantum networks, paving the way for quantum communication and distributed quantum computation.

  8. Development of novel decoy oligonucleotides: advantages of circular dumb-bell decoy.

    Science.gov (United States)

    Tomita, Naruya; Tomita, Tetsuya; Yuyama, Kazuhiko; Tougan, Takahiro; Tajima, Tsuyoshi; Ogihara, Toshio; Morishita, Ryuichi

    2003-04-01

    The inhibition of specific transcription regulatory proteins is a novel approach to regulate gene expression. The transcriptional activities of DNA binding proteins can be inhibited by the use of double-stranded oligonucleotides (ODNs) that compete for binding to their specific target sequences in promoters and enhancers. Transfection of this cis-element double-stranded ODN, referred to as decoy ODN, has been reported to be a powerful tool that provides a new class of anti-gene strategies to gene therapy and permits examination of specific gene regulation. We have demonstrated the usefulness of this decoy ODN strategy in animal models of restenosis, myocardial infarction, glomerulonephritis and rheumatoid arthritis. However, one of the major limitations of decoy ODN technology is the rapid degradation of phosphodiester ODNs by intracellular nucleases. To date, several different types of double-stranded decoy ODNs have been developed to overcome this issue. Circular dumb-bell (CD) double-stranded decoy ODNs that were developed to resolve this issue have attracted a high level of interest. In this review, the applications of decoy ODN strategy and the advantages of modified CD double-stranded decoy ODNs will be discussed.

  9. IR decoys modeling method based on particle system

    Science.gov (United States)

    Liu, Jun-yu; Wu, Kai-feng; Dong, Yan-bing

    2016-10-01

    Due to the complexity in combustion processes of IR decoys, it is difficult to describe its infrared radiation characteristics by deterministic model. In this work, the IR decoys simulation based on particle system was found. The measured date of the IR decoy is used to analyze the typical characteristic of the IR decoy. A semi-empirical model of the IR decoy motion law has been set up based on friction factors and a IR decoys simulation model has been build up based on particle system. The infrared imaging characteristic and time varying characteristic of the IR decoy were simulated by making use of the particle feature such as lifetime, speed and color. The dynamic IR decoys simulation is realized with the VC++6.0 and OpenGL.

  10. Improving decoy databases for protein folding algorithms

    KAUST Repository

    Lindsey, Aaron

    2014-01-01

    Copyright © 2014 ACM. Predicting protein structures and simulating protein folding are two of the most important problems in computational biology today. Simulation methods rely on a scoring function to distinguish the native structure (the most energetically stable) from non-native structures. Decoy databases are collections of non-native structures used to test and verify these functions. We present a method to evaluate and improve the quality of decoy databases by adding novel structures and removing redundant structures. We test our approach on 17 different decoy databases of varying size and type and show significant improvement across a variety of metrics. We also test our improved databases on a popular modern scoring function and show that they contain a greater number of native-like structures than the original databases, thereby producing a more rigorous database for testing scoring functions.

  11. Protein structure quality assessment based on the distance profiles of consecutive backbone Cα atoms [v3; ref status: indexed, http://f1000r.es/2kg

    Directory of Open Access Journals (Sweden)

    Sandeep Chakraborty

    2013-12-01

    Full Text Available Predicting the three dimensional native state structure of a protein from its primary sequence is an unsolved grand challenge in molecular biology. Two main computational approaches have evolved to obtain the structure from the protein sequence - ab initio/de novo methods and template-based modeling - both of which typically generate multiple possible native state structures. Model quality assessment programs (MQAP validate these predicted structures in order to identify the correct native state structure. Here, we propose a MQAP for assessing the quality of protein structures based on the distances of consecutive Cα atoms. We hypothesize that the root-mean-square deviation of the distance of consecutive Cα (RDCC atoms from the ideal value of 3.8 Å, derived from a statistical analysis of high quality protein structures (top100H database, is minimized in native structures. Based on tests with the top100H set, we propose a RDCC cutoff value of 0.012 Å, above which a structure can be filtered out as a non-native structure. We applied the RDCC discriminator on decoy sets from the Decoys 'R' Us database to show that the native structures in all decoy sets tested have RDCC below the 0.012 Å cutoff. While most decoy sets were either indistinguishable using this discriminator or had very few violations, all the decoy structures in the fisa decoy set were discriminated by applying the RDCC criterion. This highlights the physical non-viability of the fisa decoy set, and possible issues in benchmarking other methods using this set. The source code and manual is made available at https://github.com/sanchak/mqap and permanently available on 10.5281/zenodo.7134.

  12. The decoy matters! Hormonal and behavioural differences in the reaction of territorial European robins towards stuffed and live decoys.

    Science.gov (United States)

    Scriba, Madeleine; Goymann, Wolfgang

    2008-02-01

    Simulated territorial intrusions (STIs) represent a commonly used experimental manipulation to test behavioural and hormonal responses of birds towards conspecific intruders. They are typically either conducted with live birds in a cage or with stuffed decoys. To our knowledge, nobody has tested whether these two different kinds of stimuli elicit the same kind of behavioural and hormonal response. We compared the reactions of European robins to STIs with stuffed and live decoys to see whether these stimuli are perceived in similar ways. We conducted STIs by placing a stuffed or a live decoy in a territory, played-back robin song and recorded the behaviour for at least 10min. Then, the focal bird was caught, and a blood sample was taken to measure hormone concentrations. Males challenged with a stuffed decoy responded with more threats and movements around the decoy than males that were exposed to a live decoy. Furthermore, males challenged with a stuffed decoy had significantly higher corticosterone levels than males challenged with a live decoy. Androgen levels did not differ between treatments. The differential behavioural and corticosterone response of robins to stuffed and live decoys suggests that robins may perceive stuffed decoys as more threatening than live decoys. Future investigations using STI experiments should be aware of the potential impact different kinds of decoys may have on the behavioural and hormonal response of birds during STIs.

  13. Response of distance measures to the equation of state

    CERN Document Server

    Saini, T D; Bridle, S L; Saini, Tarun Deep; Bridle, Sarah

    2003-01-01

    We show that the distance measures (such as the luminosity and angular diameter distances) are linear functionals of the equation-of-state function w(z) of the dark energy to a fair degree of accuracy in the regimes of interest. That is, the distance measures can be expressed as a sum of (i) a constant and (ii) an integral of a weighting function multiplied by the equation of state parameter w(z). The existence of such an accurate linear response approximation has several important implications: (a) Fitting a constant w model to the data drawn from an evolving model has a simple interpretation as a weighted average of w(z). (b) Any polynomial (or other expansion coefficients can also be expressed as weighted sums of the true w(z). (c) A replacement for the commonly used heuristic equation for the effective w(z), as determined by the CMB, can be derived and the result is found to be quite close to the heuristic expression commonly used. (d) The reconstruction of w(z) by Huterer et al. (2002) can be expressed a...

  14. Role of decoy molecules in neuronal ischemic preconditioning

    Science.gov (United States)

    Panneerselvam, Mathivadhani; Patel, Piyush M.; Roth, David M.; Kidd, Michael W.; Chin-Lee, Blake; Head, Brian P.; Niesman, Ingrid R.; Inoue, Satoki; Patel, Hemal H.; Davis, Daniel P.

    2011-01-01

    Decoy receptors bind with TNF related apoptosis inducing ligands (TRAIL) but do not contain the cytoplasmic domains necessary to transduce apoptotic signals. We hypothesized that decoy receptors may confer neuronal protection against lethal ischemia after ischemic preconditioning (IPC). Mixed cortical neurons were exposed to IPC one day prior to TRAIL treatment or lethal ischemia. IPC increased decoy receptor but reduced death receptor expression compared to lethal ischemia. IPC-induced increase in decoy receptor expression was reduced by prior treatment with CAPE, a nuclear factor-kappa B inhibitor (NFκB). Expression of decoy molecules, dependent on NFκB, may mediate neuronal survival induced by IPC. PMID:21315738

  15. "Junk" DNA as a genetic decoy

    OpenAIRE

    Magueijo, Joao

    2003-01-01

    We propose that the evolutionary purpose of junk DNA is to protect the gene. Mutation agents, such as retro-viruses, hit ``decoy'' DNA most of the time. Although the argument is far from general, we propose that the percentage of junk DNA should correlate with the number of retroviruses attacking a given species. It should also anti-correlate with the ideal mutation rates (higher in insects than in mammals).

  16. Infrared ship/decoy/missile encounter model

    Science.gov (United States)

    Morin, Josee; Reid, Francoise; Morin, Andre

    1993-08-01

    Simulations of missile-ship-countermeasures engagements are used to determine the effective ways of defending a ship against infrared-guided missile threats. This paper describes one type of simulation that models the engagement of a ship deploying IR decoys by an infrared-guided seeker-head missile. This model was developed to assess the efficiency of IR decoys in protecting ships against these missiles. The simulation, Missile Infrared Decoy And Ship (MIDAS), is composed of three major blocks, the infrared scene generation, the seeker simulation and the missile dynamics simulation. The infrared scene generation block produces a three-dimensional IR scene from the target ship and flare models and transforms it into the two-dimensional IR image viewed by the seeker. The seeker simulation block is based on a generic conical scan seeker which uses a crossed-detector array for target detection. It processes the IR image to select a target and generates a steering command. The missile dynamics block computes the changes in missile trajectory according to the seeker steering command. The computations performed by each of the three blocks are explained in detail.

  17. Cyclic and Coherent States in Flocks with Topological Distance

    Directory of Open Access Journals (Sweden)

    Biplab eBhattacherjee

    2014-01-01

    Full Text Available A simple model of the two dimensional collective motion of a group of mobile agents have been studied. Like birds, these agents travel in open free space where each of them interacts with the first $n$ neighbors determined by the topological distance with a free boundary condition. Using the same prescription for interactions used in the Vicsek model with scalar noise it has been observed that the flock, in absence of the noise, arrives at a number of interesting stationary states. One of the two most prominent states is the `single sink state' where the entire flock travels along the same direction maintaining perfect cohesion and coherence. The other state is the `cyclic state' where every individual agent executes a uniform circular motion, and the correlation among the agents guarantees that the entire flock executes a pulsating dynamics i.e., expands and contracts periodically between a minimum and a maximum size of the flock. We have studied another limiting situation when refreshing rate of the interaction zone is the fastest. In this case the entire flock gets fragmented into smaller clusters of different sizes. On introduction of scalar noise a crossover is observed when the agents cross over from a ballistic motion to a diffusive motion. Expectedly the crossover time is dependent on the strength of the noise $eta$ and diverges as $eta to 0$. An even more simpler version of this model has been studied by suppressing the translational degrees of freedom of the agents but retaining their angular motion. Here agents are the spins, placed at the sites of a square lattice with periodic boundary condition. Every spin interacts with its $n$ = 2, 3 or 4 nearest neighbors. In the stationary state the entire spin pattern moves as a whole when interactions are anisotropic with $n$ = 2 and 3; but it is completely frozen when the interaction is isotropic with $n=4$. These spin configu

  18. Cyclic and Coherent States in Flocks with Topological Distance

    CERN Document Server

    Bhattacherjee, Biplab; Manna, S S

    2014-01-01

    A simple model of the two dimensional collective motion of a group of mobile agents have been studied. Like birds, these agents travel in open free space where each of them interacts with the first $n$ neighbors determined by the topological distance with a free boundary condition. Using the same prescription for interactions used in the Vicsek model with scalar noise it has been observed that the flock, in absence of the noise, arrives at a number of interesting stationary states. In the `single sink state' the entire flock maintains perfect cohesion and coherence. In the `cyclic state' every agent executes a uniform circular motion, and the entire flock executes a pulsating dynamics i.e., expands and contracts periodically between a minimum and a maximum size of the flock. When refreshing rate of the interaction zone is the fastest, the entire flock gets fragmented into smaller clusters of different sizes. On introduction of scalar noise a crossover is observed when the agents cross over from a ballistic mo...

  19. Distance Traveled and Cross-State Commuting to Opioid Treatment Programs in the United States

    Directory of Open Access Journals (Sweden)

    Andrew Rosenblum

    2011-01-01

    Full Text Available This study examined commuting patterns among 23,141 methadone patients enrolling in 84 opioid treatment programs (OTPs in the United States. Patients completed an anonymous one-page survey. A linear mixed model analysis was used to predict distance traveled to the OTP. More than half (60% the patients traveled <10 miles and 6% travelled between 50 and 200 miles to attend an OTP; 8% travelled across a state border to attend an OTP. In the multivariate model (n=17,792, factors significantly (P<.05 associated with distance were, residing in the Southeast or Midwest, low urbanicity, area of the patient's ZIP code, younger age, non-Hispanic white race/ethnicity, prescription opioid abuse, and no heroin use. A significant number of OTP patients travel considerable distances to access treatment. To reduce obstacles to OTP access, policy makers and treatment providers should be alert to patients' commuting patterns and to factors associated with them.

  20. Distance Traveled and Cross-State Commuting to Opioid Treatment Programs in the United States

    Science.gov (United States)

    Rosenblum, Andrew; Cleland, Charles M.; Fong, Chunki; Kayman, Deborah J.; Tempalski, Barbara; Parrino, Mark

    2011-01-01

    This study examined commuting patterns among 23,141 methadone patients enrolling in 84 opioid treatment programs (OTPs) in the United States. Patients completed an anonymous one-page survey. A linear mixed model analysis was used to predict distance traveled to the OTP. More than half (60%) the patients traveled <10 miles and 6% travelled between 50 and 200 miles to attend an OTP; 8% travelled across a state border to attend an OTP. In the multivariate model (n = 17,792), factors significantly (P < .05) associated with distance were, residing in the Southeast or Midwest, low urbanicity, area of the patient's ZIP code, younger age, non-Hispanic white race/ethnicity, prescription opioid abuse, and no heroin use. A significant number of OTP patients travel considerable distances to access treatment. To reduce obstacles to OTP access, policy makers and treatment providers should be alert to patients' commuting patterns and to factors associated with them. PMID:21776440

  1. High-dimensional quantum key distribution with the entangled single-photon-added coherent state

    Science.gov (United States)

    Wang, Yang; Bao, Wan-Su; Bao, Hai-Ze; Zhou, Chun; Jiang, Mu-Sheng; Li, Hong-Wei

    2017-04-01

    High-dimensional quantum key distribution (HD-QKD) can generate more secure bits for one detection event so that it can achieve long distance key distribution with a high secret key capacity. In this Letter, we present a decoy state HD-QKD scheme with the entangled single-photon-added coherent state (ESPACS) source. We present two tight formulas to estimate the single-photon fraction of postselected events and Eve's Holevo information and derive lower bounds on the secret key capacity and the secret key rate of our protocol. We also present finite-key analysis for our protocol by using the Chernoff bound. Our numerical results show that our protocol using one decoy state can perform better than that of previous HD-QKD protocol with the spontaneous parametric down conversion (SPDC) using two decoy states. Moreover, when considering finite resources, the advantage is more obvious.

  2. Application of multivariate analysis of vari-ance (MANOVA to distance refractive vari-ability and mean distance refractive state

    Directory of Open Access Journals (Sweden)

    S Abelman

    2006-01-01

    Full Text Available Refractive state can be regarded as a dynam-ic quantity. Multiple measurements of refractive state can be determined easily and rapidly on a number of different occasions using an autore-fractor. In an experimental trial undertaken by Gillan, a 30-year-old female was subjected to 30 autorefractor measurements each taken at vari-ous intervals before and after the instillation of Mydriacyl 1% (tropicamide into her right eye. The purpose of this paper is to apply multivar-iate analysis of variance (MANOVA to Gillan’s sample data in order to assess whether instillation of Mydriacyl into the eye affects variability of distance refractive state as well as mean distance refractive state as measured by an autorefractor. In  five  of  the  seven  cases  where  pairwise hypotheses  tests  were  performed,  it  is  con-cluded that at a 99% level of confidence there is no difference in variability of distance refrac-tive state before and after cycloplegia. In two of the three cases where MANOVA was applied, there is a significant difference at a 95% and at a 99% level of confidence in both variability of distance refractive state and mean distance refractive  state  with  and  without  cycloplegia.

  3. The Impact of Distance Education on Higher Education: A Case Study of the United States

    Science.gov (United States)

    Caruth, Gail D.; Caruth, Donald L.

    2013-01-01

    Distance education has been credited for bringing education to students who would not otherwise have educational opportunities. This study used a qualitative case study approach to examine the research to determine the impact of distance education on higher education in the United States. This look into the impact of distance education is…

  4. Quantum secure direct communication network with superdense coding and decoy photons

    Energy Technology Data Exchange (ETDEWEB)

    Deng Fuguo [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Li Xihan [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Li Chunyan [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Zhou Ping [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Zhou Hongyu [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China)

    2007-07-15

    A quantum secure direct communication network scheme is proposed with quantum superdense coding and decoy photons. The servers on a passive optical network prepare and measure the quantum signal, i.e. a sequence of the d-dimensional Bell states. After confirming the security of the photons received from the receiver, the sender codes his secret message on them directly. For preventing a dishonest server from eavesdropping, some decoy photons prepared by measuring one photon in the Bell states are used to replace some original photons. One of the users on the network can communicate to any other one. This scheme has the advantage of high capacity, and it is more convenient than others as only a sequence of photons is transmitted in quantum line.

  5. Energy-Sensitive and "Classical-like" Distances Between Quantum States

    CERN Document Server

    Dodonov, V V; Man'ko, V I; Wünsche, A

    1998-01-01

    We introduce the concept of the ``polarized'' distance, which distinguishes the orthogonal states with different energies. We also give new inequalities for the known Hilbert-Schmidt distance between neighbouring states and express this distance in terms of the quasiprobability distributions and the normally ordered moments. Besides, we discuss the distance problem in the framework of the recently proposed ``classical-like'' formulation of quantum mechanics, based on the symplectic tomography scheme. The examples of the Fock, coherent, ``Schroedinger cats,'' squeezed, phase, and thermal states are considered.

  6. Noncommutative Geometry of the Moyal Plane: Translation Isometries, Connes' Distance on Coherent States, Pythagoras Equality

    Science.gov (United States)

    Martinetti, Pierre; Tomassini, Luca

    2013-10-01

    We study the metric aspect of the Moyal plane from Connes' noncommutative geometry point of view. First, we compute Connes' spectral distance associated with the natural isometric action of on the algebra of the Moyal plane . We show that the distance between any state of and any of its translated states is precisely the amplitude of the translation. As a consequence, we obtain the spectral distance between coherent states of the quantum harmonic oscillator as the Euclidean distance on the plane. We investigate the classical limit, showing that the set of coherent states equipped with Connes' spectral distance tends towards the Euclidean plane as the parameter of deformation goes to zero. The extension of these results to the action of the symplectic group is also discussed, with particular emphasis on the orbits of coherent states under rotations. Second, we compute the spectral distance in the double Moyal plane, intended as the product of (the minimal unitization of) by . We show that on the set of states obtained by translation of an arbitrary state of , this distance is given by the Pythagoras theorem. On the way, we prove some Pythagoras inequalities for the product of arbitrary unital and non-degenerate spectral triples. Applied to the Doplicher- Fredenhagen-Roberts model of quantum spacetime [DFR], these two theorems show that Connes' spectral distance and the DFR quantum length coincide on the set of states of optimal localization.

  7. 1994 Wisconsin trumpeter swan decoy-rearing final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This was the sixth year of the Wisconsin Trumpeter Swan Decoy-Rearing Program at Necedah National Wildlife Refuge. Necedah NWR staff and refuge manager Bud Oliveira...

  8. Infrared decoy and obscurant modelling and simulation for ship protection

    Science.gov (United States)

    Butters, Brian; Nicholls, Edgar; Walmsley, Roy; Ayling, Richard

    2011-11-01

    Imaging seekers used in modern Anti Ship Missiles (ASMs) use a variety of counter countermeasure (CCM) techniques including guard gates and aspect ratio assessment in order to counter the use of IR decoys. In order to improve the performance of EO/IR countermeasures it is necessary to accurately configure and place the decoys using a launcher that is trainable in azimuth and elevation. Control of the launcher, decoy firing times and burst sequences requires the development of algorithms based on multi-dimensional solvers. The modelling and simulation used to derive the launcher algorithms is described including the countermeasure, threat, launcher and ship models. The launcher model incorporates realistic azimuth and elevation rates with limits on azimuth and elevation arcs of fire. A Navier Stokes based model of the IR decoy includes thermal buoyancy, cooling of the IR smoke and its extinction properties. All of these factors affect the developing size, shape and radiance of the decoy. The hot smoke also influences the performance of any co-located chaff or other obscurant material. Typical simulations are described against generic imaging ASM seekers using shape discrimination or a guard gate.

  9. Effectiveness of spinning-wing decoys varies among dabbling duck species and locations

    Science.gov (United States)

    Ackerman, Joshua T.; Eadie, J.M.; Szymanski, M.L.; Caswell, J.H.; Vrtiska, Mark P.; Raedeke, Andrew H.; Checkett, J.M.; Afton, A.D.; Moore, T.G.; Caswell, F.D.; Walters, R.A.; Humburg, D.D.; Yee, J.L.

    2006-01-01

    Spinning-wing decoys are strong attractants to ducks and inc rease kill rates over traditional decoying methods. However, it is unknown whether all duck species are attracted similarly to spinning-wing decoys and whether the effectiveness of these decoys changes with latitude. We examined the effectiveness of spinning-wing decoys for 9 species of dabbling ducks during 545 experimental hunts in California (1999-2000), Minnesota (2002), Manitoba (2001-2002), Nebraska (2000-2002), Missouri (2000-2001), and Arkansas (2001-2003). During each experimental hunt, we systematically alternated between 2 paired decoy treatments every 15-30 min (depending on study site): traditional decoys only and traditional decoys with a spinning-wing decoy. Overall, 70.2% (n=1,925) of dabbling ducks were harvested (shot and retrieved) when spinning-wing decoys were turned on, ranging from 63.6% (n=187) in Missouri to 76.4% (n=356) in Minnesota. Effectiveness of spinning-wing decoys increased with latitude of study sites. Proportions of ducks shot when spinning-wing decoys were turned on differed among species, from a low of 50.0% (n=8) for cinnamon teal (Anas cyanoptera) to a high of 79.0% (n=119) for American wigeon (A. americana). The probability of being shot when spinning-wing decoys were turned on increased with annual survival rates among species; for example, spinning-wing decoys were more effective for American wigeon and mallard (A. platyrhynchos) than they were for cinnamon teal and American green-winged teal (A. crecca). Effectiveness of spinning-wing decoys did not differ consistently by age or sex of harvested ducks. Our results indicate that the effectiveness of spinning-wing decoys differs among duck species and changes with latitude; thus, consideration of these effects may be warranted when setting harvest regulations and methods of take.

  10. Lipid-modified G4-decoy oligonucleotide anchored to nanoparticles

    DEFF Research Database (Denmark)

    Cogoi, S; Jakobsen, U; Pedersen, E B

    2016-01-01

    KRAS is mutated in >90% of pancreatic ductal adenocarcinomas. As its inactivation leads to tumour regression, mutant KRAS is considered an attractive target for anticancer drugs. In this study we report a new delivery strategy for a G4-decoy oligonucleotide that sequesters MAZ, a transcription...... factor essential for KRAS transcription. It is based on the use of palmitoyl-oleyl-phosphatidylcholine (POPC) liposomes functionalized with lipid-modified G4-decoy oligonucleotides and a lipid-modified cell penetrating TAT peptide. The potency of the strategy in pancreatic cancer cells is demonstrated...

  11. Statistical mechanics-based method to extract atomic distance-dependent potentials from protein structures.

    Science.gov (United States)

    Huang, Sheng-You; Zou, Xiaoqin

    2011-09-01

    In this study, we have developed a statistical mechanics-based iterative method to extract statistical atomic interaction potentials from known, nonredundant protein structures. Our method circumvents the long-standing reference state problem in deriving traditional knowledge-based scoring functions, by using rapid iterations through a physical, global convergence function. The rapid convergence of this physics-based method, unlike other parameter optimization methods, warrants the feasibility of deriving distance-dependent, all-atom statistical potentials to keep the scoring accuracy. The derived potentials, referred to as ITScore/Pro, have been validated using three diverse benchmarks: the high-resolution decoy set, the AMBER benchmark decoy set, and the CASP8 decoy set. Significant improvement in performance has been achieved. Finally, comparisons between the potentials of our model and potentials of a knowledge-based scoring function with a randomized reference state have revealed the reason for the better performance of our scoring function, which could provide useful insight into the development of other physical scoring functions. The potentials developed in this study are generally applicable for structural selection in protein structure prediction.

  12. Four-state continuous-variable quantum key distribution with long secure distance

    Science.gov (United States)

    Yang, Jian; Xu, Bingjie; Peng, Xiang; Guo, Hong

    2012-05-01

    The four-state continuous-variable quantum key distribution protocol has a long practical secure distance [A. Leverrier and P. Grangier, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.102.180504 102, 180504 (2009)], while it poses the difficulty of parameter estimation. We propose an improved four-state protocol where the covariance matrix can be estimated from experimental data without using the linear channel assumption, thus ensuring its unconditional security in the asymptotical limit. Our scheme maintains the advantage of high reconciliation efficiency of the four-state protocol, which ensures long practical secure distance its. Our scheme can be implemented with the current technology.

  13. Asymptotic key generation rates with phase-randomized coherent light by decoy method

    CERN Document Server

    Hayashi, M

    2007-01-01

    The asymptotic key generation (AKG) rates of quantum key distribution (QKD) with the decoy method are discussed in both the forward error correction and the reverse error correction cases when the QKD system is equipped with phase-randomized coherent light with arbitrary number of intensities. For this purpose, we derive a useful convex expansion of the phase-randomized coherent state. We also derive upper bounds of AKG rates on a natural and concrete channel model. Using these upper bounds, we numerically check that the AKG rates are almost saturated when the number of intensities is three.

  14. Baseline data on distance education offerings in deaf education teacher preparation programs in the United States.

    Science.gov (United States)

    Stryker, Deborah S

    2011-01-01

    Given that little is empirically known about the use of distance education within deaf education teacher preparation (DETP) programs, the purpose of the present study was to obtain baseline data on distance education activities in these programs. Using a census of the program coordinators of the 68 DETP programs in the United States, the researcher requested and gathered data by means of an 11-item online questionnaire. A 69% response rate was achieved (N = 47). It was found that more than half of the DETP programs offered distance education courses. Respondents indicated that asynchronous technology was used overwhelmingly more often than synchronous technology, with the Internet listed most often, followed by teleconferencing. Additional results provide information about the current status of distance education within the DETP field.

  15. Learning from decoys to improve the sensitivity and specificity of proteomics database search results.

    Directory of Open Access Journals (Sweden)

    Amit Kumar Yadav

    Full Text Available The statistical validation of database search results is a complex issue in bottom-up proteomics. The correct and incorrect peptide spectrum match (PSM scores overlap significantly, making an accurate assessment of true peptide matches challenging. Since the complete separation between the true and false hits is practically never achieved, there is need for better methods and rescoring algorithms to improve upon the primary database search results. Here we describe the calibration and False Discovery Rate (FDR estimation of database search scores through a dynamic FDR calculation method, FlexiFDR, which increases both the sensitivity and specificity of search results. Modelling a simple linear regression on the decoy hits for different charge states, the method maximized the number of true positives and reduced the number of false negatives in several standard datasets of varying complexity (18-mix, 49-mix, 200-mix and few complex datasets (E. coli and Yeast obtained from a wide variety of MS platforms. The net positive gain for correct spectral and peptide identifications was up to 14.81% and 6.2% respectively. The approach is applicable to different search methodologies--separate as well as concatenated database search, high mass accuracy, and semi-tryptic and modification searches. FlexiFDR was also applied to Mascot results and showed better performance than before. We have shown that appropriate threshold learnt from decoys, can be very effective in improving the database search results. FlexiFDR adapts itself to different instruments, data types and MS platforms. It learns from the decoy hits and sets a flexible threshold that automatically aligns itself to the underlying variables of data quality and size.

  16. Distance Higher Education Experiences of Arab Gulf Students in the United States: A Cultural Perspective

    Science.gov (United States)

    Al-Harthi, Aisha S.

    2005-01-01

    This article reports on a phenomenological research study that was undertaken to provide cultural understanding about the nature of distance education experiences of Arab graduate students pursuing degree programs in the United States. As a theoretical framework, Hofstede's international difference dimensions and Hall's concept of low and high…

  17. Robust Scheme for Long-Distance Teleportation of an Unknown Atomic State

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A scheme is presented for the long-distance teleportation of an unknown atomic state between two separated cavities. The scheme is based on the Raman coupling and cavity decay. In the scheme, the effective atom-cavity coupling strength is much smaller than the cavity decay rate and thus cavities of high quality factor are unnecesssary.

  18. Antineoplastic effect of decoy oligonucleotide derived from MGMT enhancer.

    Directory of Open Access Journals (Sweden)

    Tamar Canello

    Full Text Available Silencing of O(6-methylguanine-DNA-methyltransferase (MGMT in tumors, mainly through promoter methylation, correlates with a better therapeutic response and with increased survival. Therefore, it is conceivable to consider MGMT as a potential therapeutic target for the treatment of cancers. Our previous results demonstrated the pivotal role of NF-kappaB in MGMT expression, mediated mainly through p65/NF-kappaB homodimers. Here we show that the non-canonical NF-KappaB motif (MGMT-kappaB1 within MGMT enhancer is probably the major inducer of MGMT expression following NF-kappaB activation. Thus, in an attempt to attenuate the transcription activity of MGMT in tumors we designed locked nucleic acids (LNA modified decoy oligonucleotides corresponding to the specific sequence of MGMT-kappaB1 (MGMT-kB1-LODN. Following confirmation of the ability of MGMT-kB1-LODN to interfere with the binding of p65/NF-kappaB to the NF-KappaB motif within MGMT enhancer, the efficacy of the decoy was studied in-vitro and in-vivo. The results of these experiments show that the decoy MGMT-kB1-LODN have a substantial antineoplastic effect when used either in combination with temozolomide or as monotherapy. Our results suggest that MGMT-kB1-LODN may provide a novel strategy for cancer therapy.

  19. Antineoplastic effect of decoy oligonucleotide derived from MGMT enhancer.

    Science.gov (United States)

    Canello, Tamar; Ovadia, Haim; Refael, Miri; Zrihan, Daniel; Siegal, Tali; Lavon, Iris

    2014-01-01

    Silencing of O(6)-methylguanine-DNA-methyltransferase (MGMT) in tumors, mainly through promoter methylation, correlates with a better therapeutic response and with increased survival. Therefore, it is conceivable to consider MGMT as a potential therapeutic target for the treatment of cancers. Our previous results demonstrated the pivotal role of NF-kappaB in MGMT expression, mediated mainly through p65/NF-kappaB homodimers. Here we show that the non-canonical NF-KappaB motif (MGMT-kappaB1) within MGMT enhancer is probably the major inducer of MGMT expression following NF-kappaB activation. Thus, in an attempt to attenuate the transcription activity of MGMT in tumors we designed locked nucleic acids (LNA) modified decoy oligonucleotides corresponding to the specific sequence of MGMT-kappaB1 (MGMT-kB1-LODN). Following confirmation of the ability of MGMT-kB1-LODN to interfere with the binding of p65/NF-kappaB to the NF-KappaB motif within MGMT enhancer, the efficacy of the decoy was studied in-vitro and in-vivo. The results of these experiments show that the decoy MGMT-kB1-LODN have a substantial antineoplastic effect when used either in combination with temozolomide or as monotherapy. Our results suggest that MGMT-kB1-LODN may provide a novel strategy for cancer therapy.

  20. Action-at-a-distance electrodynamics in quasi-steady-state cosmology

    Indian Academy of Sciences (India)

    Kaustubh Sudhir Deshpande

    2014-09-01

    Action-at-a-distance electrodynamics – alternative approach to field theory – can be extended to cosmological models using conformal symmetry. An advantage of this is that, the origin of arrow of time in electromagnetism can be attributed to the cosmological structure. Different cosmological models can be investigated, based on Wheeler–Feynman absorber theory, and only those models can be considered viable for our Universe which have net full retarded electromagnetic interactions, i.e., forward direction of time. This work evaluates the quasi-steady-state model and demonstrates that it admits full retarded and not advanced solution. Thus, quasi-steady-state cosmology (QSSC) satisfies this necessary condition for a correct cosmological model, based on action-at-a-distance formulation.

  1. The University of North Carolina Report on Expanding Access to Higher Education through State-Funded Distance Education Programs

    Science.gov (United States)

    University of North Carolina General Administration, 2012

    2012-01-01

    Legislation in 1998 provided enrollment funding for UNC distance education. This report documents the growth of UNC distance education programs and their role in meeting the high priority education and economic development needs of the State. As highlighted in the Executive Summary and documented throughout this report, state enrollment funding…

  2. Spectrum-based method to generate good decoy libraries for spectral library searching in peptide identifications.

    Science.gov (United States)

    Cheng, Chia-Ying; Tsai, Chia-Feng; Chen, Yu-Ju; Sung, Ting-Yi; Hsu, Wen-Lian

    2013-05-01

    As spectral library searching has received increasing attention for peptide identification, constructing good decoy spectra from the target spectra is the key to correctly estimating the false discovery rate in searching against the concatenated target-decoy spectral library. Several methods have been proposed to construct decoy spectral libraries. Most of them construct decoy peptide sequences and then generate theoretical spectra accordingly. In this paper, we propose a method, called precursor-swap, which directly constructs decoy spectral libraries directly at the "spectrum level" without generating decoy peptide sequences by swapping the precursors of two spectra selected according to a very simple rule. Our spectrum-based method does not require additional efforts to deal with ion types (e.g., a, b or c ions), fragment mechanism (e.g., CID, or ETD), or unannotated peaks, but preserves many spectral properties. The precursor-swap method is evaluated on different spectral libraries and the results of obtained decoy ratios show that it is comparable to other methods. Notably, it is efficient in time and memory usage for constructing decoy libraries. A software tool called Precursor-Swap-Decoy-Generation (PSDG) is publicly available for download at http://ms.iis.sinica.edu.tw/PSDG/.

  3. Contextual effects and psychological features influencing decoy options: A review and research agenda

    Directory of Open Access Journals (Sweden)

    David Gonzalez-Prieto

    2013-01-01

    Full Text Available Purpose: The purpose of this paper is to develop future research proposals aiming to contribute the extant theory which explains decoy effects.Design/methodology/approach: Firstly, a review of the existing literature about decoy options and its interactions with contextual effects that could affect their performance is presented. Next, two research proposals are presented: the introduction of a double decoy choice set and the evaluation of decoy effect under different levels of cognitive effort in a purchasing process.Findings and Originality/value: For the research proposal concerning double decoy choice sets, different hypothesis are introduced based on the different theories aiming to explain the effect of simple decoy choice sets. This hypothesis predict different outcomes for the same experimental design, fact that could provide further support for at least one of the current explanations for decoy effects. Regarding the effect of decoy options under different levels of cognitive effort, implications for experimental design for sequential purchasing process are expected. Especially for those designed with complex options, with many steps or high number of options.Originality/value: Two new research proposal approaches are presented in order enhance the current theory. Moreover, both have managerial implications concerning the real usage of decoy options in reduced choice sets as well as in sequential purchasing processes.

  4. The distance between state and rural society in the PRC. Reading document no 1 (February 2004).

    Science.gov (United States)

    Weigelin-Schwiedrzik, Susanne

    2008-04-01

    While the People's Republic of China appears on a daily basis in all of the important newspapers around the world with its enormous successes in modernizing its economy, life in the Chinese countryside usually does not attract international attention. However, we know from a wide range of reports that the situation in the Chinese countryside is getting more and more complicated with local corruption, pollution and poverty growing in most parts of the country. The Chinese language press reports on a growing number of local uprisings in remote areas. While some analysts regard the situation in the countryside as a potential threat to the ongoing peaceful process of economic reform in China, China seems to be well prepared to cope with this change and the state is comparatively flexible in dealing with unrest among the rural population. So far the system itself has not been challenged by peasant discontent. This article introduces the idea that the distance between state and rural society is the basis of this flexibility. It will analyze a major policy document issued by the state and party leadership in order to show how state and rural society interact on the basis of a still insurmountable distance between state and rural society.

  5. Short distance and initial state effects in inflation: stress tensor and decoherence

    CERN Document Server

    Anderson, P R; Mottola, E; Anderson, Paul R.; Molina-Paris, Carmen; Mottola, Emil

    2005-01-01

    We present a consistent low energy effective field theory framework for parameterizing the effects of novel short distance physics in inflation, and their possible observational signatures in the Cosmic Microwave Background. We consider the class of general homogeneous, isotropic initial states for quantum scalar fields in Robertson-Walker (RW) spacetimes, subject to the requirement that their ultraviolet behavior be consistent with renormalizability of the covariantly conserved stress-energy tensor which couples to gravity. In the functional Schrodinger picture such states are coherent, squeezed, mixed states characterized by a Gaussian density matrix. This Gaussian has parameters which approach those of the adiabatic vacuum at large wave number, and evolve in time according to an effective classical Hamiltonian. The one complex parameter family of $\\alpha$ squeezed states in de Sitter spacetime does not fall into this UV allowed class, except for the special value of the parameter corresponding to the Bunch...

  6. Action-at-a-distance electrodynamics in Quasi-steady-state cosmology

    CERN Document Server

    Deshpande, Kaustubh Sudhir

    2013-01-01

    Action-at-a-distance electrodynamics - alternative approach to field theory - can be extended to cosmological models using conformal symmetry. An advantage of this is that the origin of arrow of time in electromagnetism can be attributed to the cosmological structure. Different cosmological models can be investigated, based on Wheeler-Feynman absorber theory, and only those models can be considered viable for our universe which have net full retarded electromagnetic interactions i.e. forward direction of time. This work evaluates quasi-steady-state model and demonstrates that it admits full retarded and not advanced solution. Thus QSSC satisfies this necessary condition for a correct cosmological model, based on action-at-a-distance formulation.

  7. Long-distance quantum state transfer through cavity-assisted interaction

    Institute of Scientific and Technical Information of China (English)

    Li Yu-Ning; Mei Feng; Yu Ya-Fei; and Zhang Zhi-Ming

    2011-01-01

    We propose a scheme for long-distance quantum state transfer between different atoms based on cavity-assisted interactions.In our scheme,a coherent optical pulse sequentially interacts with two distant atoms trapped in separated cavities. Through the measurement of the state of the first atom and the homodyne detection of the final output coherent light,the quantum state can be transferred into the second atom with a success probability of unity and a fidelity of unity.In addition,our scheme neither requires the high-Q cavity working in the strong coupling regime nor employs the single-photon quantum channel,which greatly relaxes the experimental requirements.

  8. Integrating population dynamics models and distance sampling data: a spatial hierarchical state-space approach.

    Science.gov (United States)

    Nadeem, Khurram; Moore, Jeffrey E; Zhang, Ying; Chipman, Hugh

    2016-07-01

    Stochastic versions of Gompertz, Ricker, and various other dynamics models play a fundamental role in quantifying strength of density dependence and studying long-term dynamics of wildlife populations. These models are frequently estimated using time series of abundance estimates that are inevitably subject to observation error and missing data. This issue can be addressed with a state-space modeling framework that jointly estimates the observed data model and the underlying stochastic population dynamics (SPD) model. In cases where abundance data are from multiple locations with a smaller spatial resolution (e.g., from mark-recapture and distance sampling studies), models are conventionally fitted to spatially pooled estimates of yearly abundances. Here, we demonstrate that a spatial version of SPD models can be directly estimated from short time series of spatially referenced distance sampling data in a unified hierarchical state-space modeling framework that also allows for spatial variance (covariance) in population growth. We also show that a full range of likelihood based inference, including estimability diagnostics and model selection, is feasible in this class of models using a data cloning algorithm. We further show through simulation experiments that the hierarchical state-space framework introduced herein efficiently captures the underlying dynamical parameters and spatial abundance distribution. We apply our methodology by analyzing a time series of line-transect distance sampling data for fin whales (Balaenoptera physalus) off the U.S. west coast. Although there were only seven surveys conducted during the study time frame, 1991-2014, our analysis detected presence of strong density regulation and provided reliable estimates of fin whale densities. In summary, we show that the integrative framework developed herein allows ecologists to better infer key population characteristics such as presence of density regulation and spatial variability in a

  9. IR seeker simulator and IR scene generation to evaluate IR decoy effectiveness; 2005BU1-EO

    NARCIS (Netherlands)

    Jong, W. de; Dam, F.A.M.; Kunz, G.J.; Schleijpen, H.M.A.

    2005-01-01

    IR decoys can be an effective countermeasure against IR guided anti ship missiles. However, it's not so easy to determine how the decoys should be deployed to get maximum effectiveness. A limitation of trials is that results are obtained for the specific trial condition only. Software tools have bee

  10. Decoy-state quantum key distribution with a leaky source

    Science.gov (United States)

    Tamaki, Kiyoshi; Curty, Marcos; Lucamarini, Marco

    2016-06-01

    In recent years, there has been a great effort to prove the security of quantum key distribution (QKD) with a minimum number of assumptions. Besides its intrinsic theoretical interest, this would allow for larger tolerance against device imperfections in the actual implementations. However, even in this device-independent scenario, one assumption seems unavoidable, that is, the presence of a protected space devoid of any unwanted information leakage in which the legitimate parties can privately generate, process and store their classical data. In this paper we relax this unrealistic and hardly feasible assumption and introduce a general formalism to tackle the information leakage problem in most of existing QKD systems. More specifically, we prove the security of optical QKD systems using phase and intensity modulators in their transmitters, which leak the setting information in an arbitrary manner. We apply our security proof to cases of practical interest and show key rates similar to those obtained in a perfectly shielded environment. Our work constitutes a fundamental step forward in guaranteeing implementation security of quantum communication systems.

  11. A Comparative Study of the Distance Education History in China and the United States: A Socio-Historical Perspective

    Science.gov (United States)

    Kang, Haijun

    2009-01-01

    The purpose of this study is to contribute to the understanding of international distance education development through comparison of the distance education historical developments in China and the United States (U.S.). This study, utilizing a document analysis method, studied historical documents, explored the historical development of…

  12. Adaptation of Decoy Fusion Strategy for Existing Multi-Stage Search Workflows

    Science.gov (United States)

    Ivanov, Mark V.; Levitsky, Lev I.; Gorshkov, Mikhail V.

    2016-09-01

    A number of proteomic database search engines implement multi-stage strategies aiming at increasing the sensitivity of proteome analysis. These approaches often employ a subset of the original database for the secondary stage of analysis. However, if target-decoy approach (TDA) is used for false discovery rate (FDR) estimation, the multi-stage strategies may violate the underlying assumption of TDA that false matches are distributed uniformly across the target and decoy databases. This violation occurs if the numbers of target and decoy proteins selected for the second search are not equal. Here, we propose a method of decoy database generation based on the previously reported decoy fusion strategy. This method allows unbiased TDA-based FDR estimation in multi-stage searches and can be easily integrated into existing workflows utilizing popular search engines and post-search algorithms.

  13. Long-distance entanglement of spin qubits via quantum Hall edge states

    Science.gov (United States)

    Yang, Guang; Hsu, Chen-Hsuan; Stano, Peter; Klinovaja, Jelena; Loss, Daniel

    2016-02-01

    The implementation of a functional quantum computer involves entangling and coherent manipulation of a large number of qubits. For qubits based on electron spins confined in quantum dots, which are among the most investigated solid-state qubits at present, architectural challenges are often encountered in the design of quantum circuits attempting to assemble the qubits within the very limited space available. Here, we provide a solution to such challenges based on an approach to realizing entanglement of spin qubits over long distances. We show that long-range Ruderman-Kittel-Kasuya-Yosida interaction of confined electron spins can be established by quantum Hall edge states, leading to an exchange coupling of spin qubits. The coupling is anisotropic and can be either Ising type or XY type, depending on the spin polarization of the edge state. Such a property, combined with the dependence of the electron spin susceptibility on the chirality of the edge state, can be utilized to gain valuable insights into the topological nature of various quantum Hall states.

  14. Regulating the New Borderlands: An Event History Analysis of State Cross-Border Distance Higher Education Policy Adoption

    Science.gov (United States)

    Milner, Patricia E.

    2013-01-01

    Cross-border state distance higher education policy is a complex web of complicated and often contradictory regulations stretching across 50 states and 14 US territories. This study examined the applicability of strategic choice theory to state higher education policy innovation in the context of the adoption of polices that regulate the distance…

  15. Effective Preprocessing Procedures Virtually Eliminate Distance-Dependent Motion Artifacts in Resting State FMRI.

    Science.gov (United States)

    Jo, Hang Joon; Gotts, Stephen J; Reynolds, Richard C; Bandettini, Peter A; Martin, Alex; Cox, Robert W; Saad, Ziad S

    2013-05-21

    Artifactual sources of resting-state (RS) FMRI can originate from head motion, physiology, and hardware. Of these sources, motion has received considerable attention and was found to induce corrupting effects by differentially biasing correlations between regions depending on their distance. Numerous corrective approaches have relied on the identification and censoring of high-motion time points and the use of the brain-wide average time series as a nuisance regressor to which the data are orthogonalized (Global Signal Regression, GSReg). We first replicate the previously reported head-motion bias on correlation coefficients using data generously contributed by Power et al. (2012). We then show that while motion can be the source of artifact in correlations, the distance-dependent bias-taken to be a manifestation of the motion effect on correlation-is exacerbated by the use of GSReg. Put differently, correlation estimates obtained after GSReg are more susceptible to the presence of motion and by extension to the levels of censoring. More generally, the effect of motion on correlation estimates depends on the preprocessing steps leading to the correlation estimate, with certain approaches performing markedly worse than others. For this purpose, we consider various models for RS FMRI preprocessing and show that WMeLOCAL, as subset of the ANATICOR discussed by Jo et al. (2010), denoising approach results in minimal sensitivity to motion and reduces by extension the dependence of correlation results on censoring.

  16. Effective Preprocessing Procedures Virtually Eliminate Distance-Dependent Motion Artifacts in Resting State FMRI

    Directory of Open Access Journals (Sweden)

    Hang Joon Jo

    2013-01-01

    Full Text Available Artifactual sources of resting-state (RS FMRI can originate from head motion, physiology, and hardware. Of these sources, motion has received considerable attention and was found to induce corrupting effects by differentially biasing correlations between regions depending on their distance. Numerous corrective approaches have relied on the identification and censoring of high-motion time points and the use of the brain-wide average time series as a nuisance regressor to which the data are orthogonalized (Global Signal Regression, GSReg. We replicate the previously reported head-motion bias on correlation coefficients and then show that while motion can be the source of artifact in correlations, the distance-dependent bias is exacerbated by GSReg. Put differently, correlation estimates obtained after GSReg are more susceptible to the presence of motion and by extension to the levels of censoring. More generally, the effect of motion on correlation estimates depends on the preprocessing steps leading to the correlation estimate, with certain approaches performing markedly worse than others. For this purpose, we consider various models for RS FMRI preprocessing and show that the local white matter regressor (WMeLOCAL, a subset of ANATICOR, results in minimal sensitivity to motion and reduces by extension the dependence of correlation results on censoring.

  17. Fine-scale features on bioreplicated decoys of the emerald ash borer provide necessary visual verisimilitude

    Science.gov (United States)

    Domingue, Michael J.; Pulsifer, Drew P.; Narkhede, Mahesh S.; Engel, Leland G.; Martín-Palma, Raúl J.; Kumar, Jayant; Baker, Thomas C.; Lakhtakia, Akhlesh

    2014-03-01

    The emerald ash borer (EAB), Agrilus planipennis, is an invasive tree-killing pest in North America. Like other buprestid beetles, it has an iridescent coloring, produced by a periodically layered cuticle whose reflectance peaks at 540 nm wavelength. The males perform a visually mediated ritualistic mating flight directly onto females poised on sunlit leaves. We attempted to evoke this behavior using artificial visual decoys of three types. To fabricate decoys of the first type, a polymer sheet coated with a Bragg-stack reflector was loosely stamped by a bioreplicating die. For decoys of the second type, a polymer sheet coated with a Bragg-stack reflector was heavily stamped by the same die and then painted green. Every decoy of these two types had an underlying black absorber layer. Decoys of the third type were produced by a rapid prototyping machine and painted green. Fine-scale features were absent on the third type. Experiments were performed in an American ash forest infested with EAB, and a European oak forest home to a similar pest, the two-spotted oak borer (TSOB), Agrilus biguttatus. When pinned to leaves, dead EAB females, dead TSOB females, and bioreplicated decoys of both types often evoked the complete ritualized flight behavior. Males also initiated approaches to the rapidly prototyped decoy, but would divert elsewhere without making contact. The attraction of the bioreplicated decoys was also demonstrated by providing a high dc voltage across the decoys that stunned and killed approaching beetles. Thus, true bioreplication with fine-scale features is necessary to fully evoke ritualized visual responses in insects, and provides an opportunity for developing insecttrapping technologies.

  18. Beyond species recognition: somatic state affects long-distance sex pheromone communication.

    Science.gov (United States)

    Chemnitz, Johanna; Jentschke, Petra C; Ayasse, Manfred; Steiger, Sandra

    2015-08-07

    Long-range sex pheromones have been subjected to substantial research with a particular focus on their biosynthesis, peripheral perception, central processing and the resulting orientation behaviour of perceivers. Fundamental to the research on sex attractants was the assumption that they primarily coordinate species recognition. However, especially when they are produced by the less limiting sex (usually males), the evolution of heightened condition dependence might be expected and long-range sex pheromones might, therefore, also inform about a signaller's quality. Here we provide, to our knowledge, the first comprehensive study of the role of a male's long-range pheromone in mate choice that combines chemical analyses, video observations and field experiments with a multifactorial manipulation of males' condition. We show that the emission of the long-distance sex pheromone of the burying beetle, Nicrophorus vespilloides is highly condition-dependent and reliably reflects nutritional state, age, body size and parasite load--key components of an individual's somatic state. Both, the quantity and ratio of the pheromone components were affected but the time invested in pheromone emission was largely unaffected by a male's condition. Moreover, the variation in pheromone emission caused by the variation in condition had a strong effect on the attractiveness of males in the field, with males in better nutritional condition, of older age, larger body size and bearing less parasites being more attractive. That a single pheromone is influenced by so many aspects of the somatic state and causes such variation in a male's attractiveness under field conditions was hitherto unknown and highlights the need to integrate indicator models of sexual selection into pheromone research.

  19. Simulation of two-dimensional ISAR decoys on a moving platform

    Institute of Scientific and Technical Information of China (English)

    Xiaoyi Pan; Wei Wang; Qixiang Fu; Dejun Feng; Guoyu Wang

    2015-01-01

    It is potential y useful to perform deception jamming using the digital image synthesizer (DIS) since it can form a two-dimensional (2D) decoy but suffers from multiple decoys ge-neration. Inspired by the intermittent sampling repeater jamming (ISRJ), the generation of inverse synthetic aperture radar (ISAR) decoys is addressed, associated with the DIS and the ISRJ. Radar pulses are sampled intermittently and modulated by the scatter-ing model of a false target by mounting the jammer on a moving platform, and then the jamming signals are retransmitted to the radar and a train of decoys are induced after ISAR imaging. A scattering model of Yak-42 is adopted as the false-target mo-dulation model to verify the effectiveness of the jamming method based on the standard ISAR motion compensation and image for-mation procedure.

  20. Method of Monitoring Wearing and Breakage States of Cutting Tools Based on Mahalanobis Distance Features

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Mahalanobis distance features proposed by P.C.Mahalanobis, an Indian statistician, can be used in an automatic on-line cutting tool condition monitoring process based on digital image processing. In this paper, a new method of obtaining Mahalanobis distance features from a tool image is proposed. The key of calculating Mahalanobis distance is appropriately dividing the object into several component sets. Firstly, a technique is proposed that can automatically divide the component groups for calculati...

  1. HZ Her: Stellar Radius from X-ray Eclipse Observations, Evolutionary State and a New Distance

    CERN Document Server

    Leahy, D A

    2014-01-01

    Observations of HZ Her/ Her X-1 by the Rossi X-ray Timing Explorer (RXTE) covering high state eclipses of the neutron star are analyzed here. Models of the eclipse are used to measure the radius and atmospheric scale height of HZ Her, the stellar companion to the neutron star. The radius is 2.61 to 3.03 $\\times10^{11}$ cm, depending on system inclination and mass ratio(q), with accuracy of $\\sim$1 part in 1000 for given inclination and q. We fit Kurucz model stellar atmosphere models to archival optical observations. The resulting effective temperature ($T_{eff}$) of the unheated face of HZ Her is determined to be in the 2$\\sigma$ range 7440K to 7620K, and metallicity ($log(Z/Z_{\\odot})$) in the range -0.14 to +.08. The model atmosphere surface flux and new radius yield a new distance to HZ Her/ Her X-1, depending on system inclination and q. We calculate stellar evolution models for the range of allowed masses (from orbital parameters), and allowed metallicities (from optical spectrum fits). The stellar mode...

  2. The Impact of Travel Distance on Breast Reconstruction in the United States

    Science.gov (United States)

    Albornoz, Claudia R.; Cohen, Wess A.; Razdan, Shantanu N.; Mehrara, Babak J.; McCarthy, Colleen M.; Disa, Joseph J.; Dayan, Joseph H.; Pusic, Andrea L.; Cordeiro, Peter G.; Matros, Evan

    2016-01-01

    Background Inadequate access to breast reconstruction was a motivating factor underlying passage of the Women’s Health and Cancer Rights Act. It remains unclear whether all patients interested in breast reconstruction undergo this procedure. The aim of this study was to determine whether geographic disparities are present that limit the rate and method of postmastectomy reconstruction. Methods Travel distance in miles between the patient’s residence and the hospital reporting the case was used as a quantitative measure of geographic disparities. The American College of Surgeons National Cancer Database was queried for mastectomy with or without reconstruction performed from 1998 to 2011. Reconstructive procedures were categorized as implant or autologous techniques. Standard statistical tests including linear regression were performed. Results Patients who underwent breast reconstruction had to travel farther than those who had mastectomy alone (p reconstruction rates (p reconstruction at community, comprehensive community, or academic programs were 10.3, 19.9, and 26.2 miles, respectively (p Reconstruction rates were significantly greater at academic programs. Patients traveled farther to undergo autologous compared with prosthetic reconstruction. Conclusions Although greater patient awareness and insurance coverage have contributed to increased breast reconstruction rates in the United States, the presence of geographic barriers suggests an unmet need. Academic programs have the greatest reconstruction rates, but are located farther from patients’ residences. Increasing the number of plastics surgeons, especially in community centers, would be one method of addressing this inequality. PMID:26710002

  3. Effect of Stathmin Decoy-oligodeoxynucleotides on the Proliferation and Differentiation of Precartilainous Stem Cells

    Institute of Scientific and Technical Information of China (English)

    GUO Fengjing; ZHANG Yibei; CHEN Anmin

    2007-01-01

    By using decoy-oligodeoxynucleotides (decoy-ODNS) technique, the effects of Stathmin gene on the proliferation and differentiation of in vitro cultured precartilainous stem cells (PSCs) were investigated. The Stathmin decoy-ODNs were transfected into PSCs in rats by using gene trans- fection technique. Under the induction of cortisol (1 μmol/L), electrophoretic mobility shift assay was used the inhibitory effects of decoy-ODNS on Stathmin gene. MTT and cytometry were used to test the cell proliferation. The expression of collagen Ⅱ and Ⅴ and Stathmin protein was detected by using Western blot. The results showed that Stathmin decoy-ODNs inhibited the Stathmin activity in a dose-dependent manner. When the concentration of decoy-ODNs was 10 times of standard con- centration, the proliferation of PSCs was obviously suppressed and the differentiation happened. Compared to the control group, the difference was significant (P<0.05). It was concluded that de-coy-ODNs could inhibit the proliferation and promote the differentiation of PSCs by antagonizing Stathmin activity.

  4. NFkappaB decoy oligodeoxynucleotides ameliorates osteoporosis through inhibition of activation and differentiation of osteoclasts.

    Science.gov (United States)

    Shimizu, H; Nakagami, H; Tsukamoto, I; Morita, S; Kunugiza, Y; Tomita, T; Yoshikawa, H; Kaneda, Y; Ogihara, T; Morishita, R

    2006-06-01

    The transcription factor, nuclear factor-kappa B (NFkappaB), is believed to play a pivotal role in osteoclast formation. In this study, we focused on NFkappaB decoy oligodeoxynucleotides (ODN) as a new therapeutic strategy to attenuate osteoporosis. Tartrate-resistant acid phosphatase (TRAP)-positive multinuclear osteoclasts formed in mononuclear cells including osteoclast precursors from neonatal rabbit bone marrow were increased in the presence of 1,25-dihydroxyvitamin D3, whereas transfection of NFkappaB decoy ODN decreased the number of TRAP-positive cells and attenuated RANKL and M-CSF-induced osteoclast formation. NFkappaB decoy ODN also inhibited the activity of osteoclasts, as assessed by pit formation. In rat ovariectomized model of estrogen deficiency, continuous administration of NFkappaB decoy ODN attenuated the increase of TRAP activity, accompanied by a significant increase in calcium concentration in tibia and femur and decrease in urinary deoxypyridinoline. In additional osteoporosis model using vitamin C-deficient rat, inhibition of NFkappaB by decoy ODN dramatically improved the bone length, weight, density as assessed by dual-energy X-ray absorptiometry. Overall, inhibition of NFkappaB by decoy strategy prevented osteoporosis through the inhibition of bone resorption. Targeting of NFkappaB might be potential therapy in various bone metabolic diseases.

  5. Internuclear-distance dependence of the role of excited states in high-order-harmonic generation of H2+

    DEFF Research Database (Denmark)

    Han, Yong-Chang; Madsen, Lars Bojer

    2013-01-01

    equilibrium value where also recombination to the 2Σg+ (1sσg) ground state dominates. As the internuclear distance is increased, the minimum first shifts in position compared with the prediction of the two-center interference model and subsequently disappears. These effects are caused by the excited 2Σu+ (2......pσu) state, partly due to the interference between the amplitudes of recombination to the ground and excited states, but also partly due to the signal associated with recombination to the excited state alone. We find that at internuclear distances beyond R≃3 a.u. the signal close to the harmonic...... cutoff may be completely dominated by recombination into the excited 2Σu+ (2pσu) state....

  6. Enrollment in Distance Education Courses, by State: Fall 2012. Web Tables. NCES 2014-023

    Science.gov (United States)

    National Center for Education Statistics, 2014

    2014-01-01

    Postsecondary enrollment in distance education courses, particularly those offered online, has rapidly increased in recent years (Allen and Seaman 2013). Traditionally, distance education offerings and enrollment levels have varied across different types of institutions. For example, researchers have found that undergraduate enrollment in at least…

  7. Using decoy effects to influence an online brand choice: the role of price-quality trade-offs.

    Science.gov (United States)

    Hsu, Huei-Chen; Liu, Wen-Liang

    2011-04-01

    This research aims to investigate decoy effects on online brand choices. To assess the influence of decoys, we test decoy effects on three constructs-product involvement, judgment conditions, and decoy conditions-within an online experiment. A survey of 635 Internet users and a 2 × 2 × 3 ANOVA between-subjects experimental design is used to guide the research design and the systematic analysis procedure. A major finding of this study is that a standard decoy seems to have a significant effect on an advertised (target) brand for high-involvement products; from the survey, it is also apparent that competitors can also use inferior decoys to increase brand preference for low-involvement products.

  8. MANPADS protection for civil aircraft using an expendable decoy

    Science.gov (United States)

    Walmsley, Roy H.; Friede, Johan; Millwood, Nicolas; Butters, Brian

    2009-09-01

    With the ever present threat of MANPADS throughout the world the protection of civil aircraft is a desirable capability that has special requirements in terms of certification, safety, logistics, affordability, environmental impact and exportability. The Civil Aircraft Missile Protection System (CAMPS), which includes the CIV-IR (infrared) leaf-based pyrophoric (not pyrotechnic) expendable countermeasure, is a system designed to meet these requirements. This paper presents the operating aspects of the decoy, including discussion of design features necessary to ensure safety both on the ground and in flight and assure successful deployment. The characteristics of the CIV-IR have been measured, both on static single leaves in the laboratory and on deployed packs in field tests and aircraft trials. These measured properties have been used in engagement modelling and simulation to assess the level of protection that can be afforded to commercial airliners against generation 1 and 2 MANPADS threats. Aircraft flight trials with ground based seekers have also been carried out to validate the modelling work. These combine to define the deployment patterns necessary for a successful seduction of the MANPAD.

  9. Helicity conservation in inclusive nonleptonic decay B to VX Test of long-distance final state interaction

    CERN Document Server

    Suzuki, M

    2002-01-01

    The polarization measurement in the inclusive B decay provides us with a simple test of how much the long-distance final-state interaction takes place as the energy of the observed meson varies in the final state. We give the expectation of the perturbative QCD for the energy dependence of the helicity fractions in a semiquantitative form. Experiment will tell us for which decay processes the perturbative calculation should be applicable.

  10. PRESENT STATE OF DISTANCE COURSES IMPLEMENTATION AT HIGHER SCHOOLS OF UKRAINE

    Directory of Open Access Journals (Sweden)

    Olha V. Ivaniv

    2010-08-01

    Full Text Available The article deals with the distance courses (DC implementation of different subjects (economics, information and communication technologies, technical, and humanitarian disciplines at higher educational institutions of Ukraine till 2009 as well as the first attempts to create a bank and a database for the DCs. The article is accompanied by a lists of distance learning courses, separately for each of the above mentioned five themes established at the eight universities in this country.

  11. DECK: Distance and environment-dependent, coarse-grained, knowledge-based potentials for protein-protein docking

    Directory of Open Access Journals (Sweden)

    Vakser Ilya A

    2011-07-01

    Full Text Available Abstract Background Computational approaches to protein-protein docking typically include scoring aimed at improving the rank of the near-native structure relative to the false-positive matches. Knowledge-based potentials improve modeling of protein complexes by taking advantage of the rapidly increasing amount of experimentally derived information on protein-protein association. An essential element of knowledge-based potentials is defining the reference state for an optimal description of the residue-residue (or atom-atom pairs in the non-interaction state. Results The study presents a new Distance- and Environment-dependent, Coarse-grained, Knowledge-based (DECK potential for scoring of protein-protein docking predictions. Training sets of protein-protein matches were generated based on bound and unbound forms of proteins taken from the DOCKGROUND resource. Each residue was represented by a pseudo-atom in the geometric center of the side chain. To capture the long-range and the multi-body interactions, residues in different secondary structure elements at protein-protein interfaces were considered as different residue types. Five reference states for the potentials were defined and tested. The optimal reference state was selected and the cutoff effect on the distance-dependent potentials investigated. The potentials were validated on the docking decoys sets, showing better performance than the existing potentials used in scoring of protein-protein docking results. Conclusions A novel residue-based statistical potential for protein-protein docking was developed and validated on docking decoy sets. The results show that the scoring function DECK can successfully identify near-native protein-protein matches and thus is useful in protein docking. In addition to the practical application of the potentials, the study provides insights into the relative utility of the reference states, the scope of the distance dependence, and the coarse-graining of

  12. Tumor endothelium marker-8 based decoys exhibit superiority over capillary morphogenesis protein-2 based decoys as anthrax toxin inhibitors.

    Directory of Open Access Journals (Sweden)

    Chenguang Cai

    Full Text Available Anthrax toxin is the major virulence factor produced by Bacillus anthracis. The toxin consists of three protein subunits: protective antigen (PA, lethal factor, and edema factor. Inhibition of PA binding to its receptors, tumor endothelium marker-8 (TEM8 and capillary morphogenesis protein-2 (CMG2 can effectively block anthrax intoxication, which is particularly valuable when the toxin has already been overproduced at the late stage of anthrax infection, thus rendering antibiotics ineffectual. Receptor-like agonists, such as the mammalian cell-expressed von Willebrand factor type A (vWA domain of CMG2 (sCMG2, have demonstrated potency against the anthrax toxin. However, the soluble vWA domain of TEM8 (sTEM8 was ruled out as an anthrax toxin inhibitor candidate due to its inferior affinity to PA. In the present study, we report that L56A, a PA-binding-affinity-elevated mutant of sTEM8, could inhibit anthrax intoxication as effectively as sCMG2 in Fisher 344 rats. Additionally, pharmacokinetics showed that L56A and sTEM8 exhibit advantages over sCMG2 with better lung-targeting and longer plasma retention time, which may contribute to their enhanced protective ability in vivo. Our results suggest that receptor decoys based on TEM8 are promising anthrax toxin inhibitors and, together with the pharmacokinetic studies in this report, may contribute to the development of novel anthrax drugs.

  13. Fabrication of Polymeric Visual Decoys for the Male Emerald Ash Borer (Agrilus planipennis)

    Institute of Scientific and Technical Information of China (English)

    Drew P. Pulsifer; Akhlesh Lakhtakia; Mahesh S. Narkhede; Michael J. Domingue; Beverly G. Post; Jayant Kumar; Raúl J. Martín-Palma

    2013-01-01

    Through a bioreplication approach,we have fabricated artificial visual decoys for the invasive species Agrilus planipennis—commonly known as the Emerald Ash Borer (EAB).The mating behavior of this species involves an overflying EAB male pouncing on an EAB female at rest on an ash leaflet before copulating.The male spots the female on the leaflet by visually detecting the iridescent green color of the female's elytra.As rearing EAB and then deploying dead females as decoys for trapping is both arduous and inconvenient,we decided to fabricate artificial decoys.We used a dead female to make a negative die of nickel and a positive die of epoxy.Decoys were then made by first depositing a quarter-wave-stack Bragg reflector on a polymer sheet and then stamping it with a pair of matched negative and positive dies to take the shape of the upper surface of an EAB female.As nearly 100 artificial decoys were fabricated from just one EAB female,this bioreplication process is industrially scalable.Preliminary results from a field trapping test are indicative of success.

  14. Higher Education Distance Learning in Portugal--State of the Art and Current Policy Issues

    Science.gov (United States)

    Hasan, Abrar; Laaser, Wolfram

    2010-01-01

    The paper is based on a recent report given to the Portuguese Ministry of Science, Technology and Higher Education on "Reforming Higher Education Distance Learning in Portugal" (Hasan et. al. 2009). The report was grounded on on-site visits of leading Portuguese Universities, Polytechnics and Business Schools as well as on written…

  15. Distance Learning and Skill Acquisition in Engineering Sciences: Present State and Prospects

    Science.gov (United States)

    Potkonjak, Veljko; Jovanovic, Kosta; Holland, Owen; Uhomoibhi, James

    2013-01-01

    Purpose: The purpose of this paper is to present an improved concept of software-based laboratory exercises, namely a Virtual Laboratory for Engineering Sciences (VLES). Design/methodology/approach: The implementation of distance learning and e-learning in engineering sciences (such as Mechanical and Electrical Engineering) is still far behind…

  16. Representing distance, consuming distance

    DEFF Research Database (Denmark)

    Larsen, Gunvor Riber

    to mobility and its social context. Such an understanding can be approached through representations, as distance is being represented in various ways, most noticeably in maps and through the notions of space and Otherness. The question this talk subsequently asks is whether these representations of distance...... are being consumed in the contemporary society, in the same way as places, media, cultures and status are being consumed (Urry 1995, Featherstone 2007). An exploration of distance and its representations through contemporary consumption theory could expose what role distance plays in forming...... are present in theoretical and empirical elaborations on mobility, but these remain largely implicit and unchallenged (Bauman 1998). This talk will endeavour to unmask distance as a theoretical entity by exploring ways in which distance can be understood and by discussing distance through its representations...

  17. Action-at-a-distance electrodynamics in Quasi-steady-state cosmology

    OpenAIRE

    Deshpande, Kaustubh Sudhir

    2013-01-01

    Action-at-a-distance electrodynamics - alternative approach to field theory - can be extended to cosmological models using conformal symmetry. An advantage of this is that the origin of arrow of time in electromagnetism can be attributed to the cosmological structure. Different cosmological models can be investigated, based on Wheeler-Feynman absorber theory, and only those models can be considered viable for our universe which have net full retarded electromagnetic interactions i.e. forward ...

  18. Engineering and performance standards parameters for long distance road transport in the United States: the special case of horses

    Directory of Open Access Journals (Sweden)

    Carolyn L. Stull

    2008-03-01

    Full Text Available The transportation conditions of slaughter horses for human consumption have become a public and regulatory issue in the United States in the last two decades. Federal regulations were developed partially using the results of funded research projects that examined the types of vehicles, characteristics of slaughter horse candidates, types of injuries during transport, duration of transit, stocking densities and other behavioural and physiological indices during long-distance road transport. Additionally, the physiological responses of horses travelling long distances in vans while cross-tied by their halters in individual stalls were also studied. Both engineering- and performance-based standards were developed from the scientific studies and implemented in the federal regulations to ensure the humane movement of equines to slaughter facilities via commercial road transportation.

  19. Optimized distance-dependent atom-pair-based potential DOOP for protein structure prediction.

    Science.gov (United States)

    Chae, Myong-Ho; Krull, Florian; Knapp, Ernst-Walter

    2015-05-01

    The DOcking decoy-based Optimized Potential (DOOP) energy function for protein structure prediction is based on empirical distance-dependent atom-pair interactions. To optimize the atom-pair interactions, native protein structures are decomposed into polypeptide chain segments that correspond to structural motives involving complete secondary structure elements. They constitute near native ligand-receptor systems (or just pairs). Thus, a total of 8609 ligand-receptor systems were prepared from 954 selected proteins. For each of these hypothetical ligand-receptor systems, 1000 evenly sampled docking decoys with 0-10 Å interface root-mean-square-deviation (iRMSD) were generated with a method used before for protein-protein docking. A neural network-based optimization method was applied to derive the optimized energy parameters using these decoys so that the energy function mimics the funnel-like energy landscape for the interaction between these hypothetical ligand-receptor systems. Thus, our method hierarchically models the overall funnel-like energy landscape of native protein structures. The resulting energy function was tested on several commonly used decoy sets for native protein structure recognition and compared with other statistical potentials. In combination with a torsion potential term which describes the local conformational preference, the atom-pair-based potential outperforms other reported statistical energy functions in correct ranking of native protein structures for a variety of decoy sets. This is especially the case for the most challenging ROSETTA decoy set, although it does not take into account side chain orientation-dependence explicitly. The DOOP energy function for protein structure prediction, the underlying database of protein structures with hypothetical ligand-receptor systems and their decoys are freely available at http://agknapp.chemie.fu-berlin.de/doop/.

  20. Distance to achieve steady state walking speed in frail elderly persons

    NARCIS (Netherlands)

    Lindemann, U.; Najafi, B.; Zijlstra, W.; Hauer, K.; Muche, R.; Becker, C.; Aminian, K.

    2008-01-01

    This study aims to determine the length of the gait initiation phase before achieving steady state walking in frail older people. Based on body fixed sensors, habitual walking was analysed in 116 community-dwelling older persons (mean age 83.1 years, 84% women). The start of steady state walking was

  1. CLUB-MARTINI: Selecting Favourable Interactions amongst Available Candidates, a Coarse-Grained Simulation Approach to Scoring Docking Decoys.

    Directory of Open Access Journals (Sweden)

    Qingzhen Hou

    Full Text Available Large-scale identification of native binding orientations is crucial for understanding the role of protein-protein interactions in their biological context. Measuring binding free energy is the method of choice to estimate binding strength and reveal the relevance of particular conformations in which proteins interact. In a recent study, we successfully applied coarse-grained molecular dynamics simulations to measure binding free energy for two protein complexes with similar accuracy to full-atomistic simulation, but 500-fold less time consuming. Here, we investigate the efficacy of this approach as a scoring method to identify stable binding conformations from thousands of docking decoys produced by protein docking programs. To test our method, we first applied it to calculate binding free energies of all protein conformations in a CAPRI (Critical Assessment of PRedicted Interactions benchmark dataset, which included over 19000 protein docking solutions for 15 benchmark targets. Based on the binding free energies, we ranked all docking solutions to select the near-native binding modes under the assumption that the native-solutions have lowest binding free energies. In our top 100 ranked structures, for the 'easy' targets that have many near-native conformations, we obtain a strong enrichment of acceptable or better quality structures; for the 'hard' targets without near-native decoys, our method is still able to retain structures which have native binding contacts. Moreover, in our top 10 selections, CLUB-MARTINI shows a comparable performance when compared with other state-of-the-art docking scoring functions. As a proof of concept, CLUB-MARTINI performs remarkably well for many targets and is able to pinpoint near-native binding modes in the top selections. To the best of our knowledge, this is the first time interaction free energy calculated from MD simulations have been used to rank docking solutions at a large scale.

  2. Application of decoy oligonucleotides as novel therapeutic strategy: a contemporary overview.

    Science.gov (United States)

    Ahmad, Mohammad Zaki; Akhter, Sohail; Mallik, Neha; Anwar, Mohammad; Tabassum, Wajda; Ahmad, Farhan Jalees

    2013-03-01

    Molecular therapy is emerging as a potential strategy for the treatment of many diseases. Correct regulation of gene expression is essential for both, to normal development and proper functioning of the all the organisms. Even after four decades of intensive research, it is still a major problem from regulatory and technical point of view, to replace defective genes. The technology of decoy oligonucleotides has received considerable attention to treat and cure a variety of diseases and abnormal physiological conditions, because they provide a rational way to design and selective regulation of a specific gene expression. Decoy oligonucleotides are widely used as inhibitors of specific gene expression because they can offer exciting possibility of expression and blocking of a particular gene without any changes in the functions of other genes. Advances in the decoy oligonucleotides are rapidly paving the way to new insights into the origin and treatment of inflammatory, cancer and/or other immune disorders. The review covers the progress achieved towards the development of decoy oligonucleotides as a potential strategy in a new class of molecular therapy.

  3. Modelling infrared signatures of ships and decoys for countermeasure effectiveness studies

    NARCIS (Netherlands)

    Schleijpen, H.M.A.; Degache, M.A.C.; Veerman, H.E.T.; Sweeden, R. van; Devecchi, B.A.

    2012-01-01

    Infrared guided missiles are a threat for modern naval forces. The vulnerability of ships can be reduced by applying countermeasures such as infrared decoys and infrared signature reduction. This paper presents recent improvements in a simulation toolset which can be used for assessing the

  4. Delayed toxicity associated with soluble anthrax toxin receptor decoy-Ig fusion protein treatment.

    Directory of Open Access Journals (Sweden)

    Diane Thomas

    Full Text Available Soluble receptor decoy inhibitors, including receptor-immunogloubulin (Ig fusion proteins, have shown promise as candidate anthrax toxin therapeutics. These agents act by binding to the receptor-interaction site on the protective antigen (PA toxin subunit, thereby blocking toxin binding to cell surface receptors. Here we have made the surprising observation that co-administration of receptor decoy-Ig fusion proteins significantly delayed, but did not protect, rats challenged with anthrax lethal toxin. The delayed toxicity was associated with the in vivo assembly of a long-lived complex comprised of anthrax lethal toxin and the receptor decoy-Ig inhibitor. Intoxication in this system presumably results from the slow dissociation of the toxin complex from the inhibitor following their prolonged circulation. We conclude that while receptor decoy-Ig proteins represent promising candidates for the early treatment of B. anthracis infection, they may not be suitable for therapeutic use at later stages when fatal levels of toxin have already accumulated in the bloodstream.

  5. Virus encoded MHC-like decoys diversify the inhibitory KIR repertoire.

    Directory of Open Access Journals (Sweden)

    Paola Carrillo-Bustamante

    Full Text Available Natural killer (NK cells are circulating lymphocytes that play an important role in the control of viral infections and tumors. Their functions are regulated by several activating and inhibitory receptors. A subset of these receptors in human NK cells are the killer immunoglobulin-like receptors (KIRs, which interact with the highly polymorphic MHC class I molecules. One important function of NK cells is to detect cells that have down-regulated MHC expression (missing-self. Because MHC molecules have non polymorphic regions, their expression could have been monitored with a limited set of monomorphic receptors. Surprisingly, the KIR family has a remarkable genetic diversity, the function of which remains poorly understood. The mouse cytomegalovirus (MCMV is able to evade NK cell responses by coding "decoy" molecules that mimic MHC class I. This interaction was suggested to have driven the evolution of novel NK cell receptors. Inspired by the MCMV system, we develop an agent-based model of a host population infected with viruses that are able to evolve MHC down-regulation and decoy molecules. Our simulations show that specific recognition of MHC class I molecules by inhibitory KIRs provides excellent protection against viruses evolving decoys, and that the diversity of inhibitory KIRs will subsequently evolve as a result of the required discrimination between host MHC molecules and decoy molecules.

  6. Genetic diversity and antimicrobial resistance of Campylobacter and Salmonella strains isolated from decoys and raptors.

    Science.gov (United States)

    Jurado-Tarifa, E; Torralbo, A; Borge, C; Cerdà-Cuéllar, M; Ayats, T; Carbonero, A; García-Bocanegra, I

    2016-10-01

    Infections caused by thermotolerant Campylobacter spp. and Salmonella spp. are the leading causes of human gastroenteritis worldwide. Wild birds can act as reservoirs of both pathogens. A survey was carried out to determine the prevalence, genetic diversity and antimicrobial resistance of thermotolerant Campylobacter and Salmonella in waterfowl used as decoys and wild raptors in Andalusia (Southern Spain). The overall prevalence detected for Campylobacter was 5.9% (18/306; CI95%: 3.25-8.52) in decoys and 2.3% (9/387; CI95%: 0.82-3.83) in wild raptors. Isolates were identified as C. jejuni, C. coli and C. lari in both bird groups. Salmonella was isolated in 3.3% (10/306; CI95%: 2.3-4.3) and 4.6% (18/394; CI95%: 3.5-5.6) of the decoys and raptors, respectively. Salmonella Enteritidis and Typhimurium were the most frequently identified serovars, although Salmonella serovars Anatum, Bredeney, London and Mikawasima were also isolated. Pulsed-field gel electrophoresis analysis of isolates showed higher genetic diversity within Campylobacter species compared to Salmonella serovars. Campylobacter isolates showed resistance to gentamicin, ciprofloxacin and tetracycline, while resistance to erythromycin and tetracycline was found in Salmonella isolates. The results indicate that both decoys and raptors can act as natural carriers of Campylobacter and Salmonella in Spain, which may have important implications for public and animal health.

  7. Prolongation of liver allograft survival by dendritic cells modified with NF-κB decoy oligodeoxynucleotides

    Institute of Scientific and Technical Information of China (English)

    Ming-Qing Xu; Yu-Ping Suo; Jian-Ping Gong; Ming-Man Zhang; Lü-Nan Yan

    2004-01-01

    AIM: To induce the tolerance of rat liver allograft by dendritic cells (DCs) modified with NF-κB decoy oligodeoxynucleotides (ODNs).METHODS: Bone marrow (BM)-derived DCs from SD rats were propagated in the presence of GM-CSF or GM-CSF+IL-4to obtain immature DCs or mature DCs. GM-CSF+IL-4-propagated DCs were treated with double-strand NF-κB decoy ODNs containing two NF-κB binding sites or scrambled ODNs to ascertain whether NF-κB decoy ODNs might prevent DC maturation. GM-CSF-propagated DCs, GMCSF+NF-κB decoy ODNs or scrambled ODNs-propagated DCs were treated with LPS for 18 h to determine whether NF-κB decoy ODNs could prevent LPS-induced IL-12production in DCs. NF-κB binding activities, costimulatory molecule (CD40, CD80, CD86) surface expression, IL-12protein expression and allostimulatory capacity of DCs were measured with electrophoretic mobility shift assay (EMSA),flow cytometry, Western blotting, and mixed lymphocyte reaction (MLR), respectively. GM-CSF-propagated DCs, GMCSF+IL-4 -propagated DCs, and GM-CSF+NF-κB decoy ODNs or scrambled ODNs-propagated DCs were injected intravenously into recipient LEW rats 7 d prior to liver transplantation and immediately after liver transplantation.Histological grading of liver graft rejection was determined 7 d after liver transplantation. Expression of IL-2, IL-4 and IFN-γ mRNA in liver graft and in recipient spleen was analyzed by semiquantitative RT-PCR. Apoptosis of liver allograft-infiltrating cells was measured with TUNEL staining.RESULTS: GM-CSF-propagated DCs, GM-CSF+NF-κB decoy ODNs-propagated DCs and GM-CSF+ scrambled ODNspropagated DCs exhibited features of immature DCs, with similar low level of costimulatory molecule(CD40, CD80,CD86) surface expression, absence of NF-κB activation,and few allocostimulatory activities. GM-CSF+IL-4-propagated DCs displayed features of mature DCs, with high levels of costimulatory molecule (CD40, CD80, CD86) surface expression, marked NF-κB activation, and

  8. STAT3 Decoy Oligodeoxynucleotides-Loaded Solid Lipid Nanoparticles Induce Cell Death and Inhibit Invasion in Ovarian Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Yanhui Ma

    Full Text Available Recent advances in the synthesis of multi-functional nanoparticles have opened up tremendous opportunities for the targeted delivery of genes of interest. Cationic solid lipid nanoparticles (SLN can efficiently bind nucleic acid molecules and transfect genes in vitro. Few reports have combined SLN with therapy using decoy oligodeoxynucleotides (ODN. In the present study, we prepared SLN to encapsulate STAT3 decoy ODN; then, the properties and in vitro behavior of SLN-STAT3 decoy ODN complexes were investigated. SLN-STAT3 decoy ODN complexes were efficiently taken up by human ovarian cancer cells and significantly suppressed cell growth. Blockage of the STAT3 pathway by SLN-STAT3 decoy ODN complexes resulted in an evident induction of cell death, including apoptotic and autophagic death. The mechanism involved the increased expression of cleaved caspase 3, Bax, Beclin-1 and LC3-II and reduced expression of Bcl-2, pro-caspase 3, Survivin, p-Akt and p-mTOR. In addition, SLN-STAT3 decoy ODN complexes inhibited cell invasion by up-regulating E-cadherin expression and down-regulating Snail and MMP-9 expression. These findings confirmed that SLN as STAT3 decoy ODN carriers can induce cell death and inhibit invasion of ovarian cancer cells. We propose that SLN represent a potential approach for targeted gene delivery in cancer therapy.

  9. 3D time-of-flight distance measurement with custom solid-state image sensors in CMOS/CCD-technology

    OpenAIRE

    Lange, Robert de

    2006-01-01

    Three-D time-of-flight distance measurement with custom solid-state image sensors in CMOS/CCD-technology Da wir in einer dreidimensionalen Welt leben, erfordert eine geeignete Beschreibung unserer Umwelt für viele Anwendungen Kenntnis über die relative Position und Bewegung der verschiedenen Objekte innerhalb einer Szene. Die daraus resultierende Anforderung räumlicher Wahrnehmung ist in der Natur dadurch gelöst, daß die meisten Tiere mindestens zwei Augen haben. Diese Fähigkeit des Stere...

  10. On the importance of the distance measures used to train and test knowledge-based potentials for proteins.

    Science.gov (United States)

    Carlsen, Martin; Koehl, Patrice; Røgen, Peter

    2014-01-01

    Knowledge-based potentials are energy functions derived from the analysis of databases of protein structures and sequences. They can be divided into two classes. Potentials from the first class are based on a direct conversion of the distributions of some geometric properties observed in native protein structures into energy values, while potentials from the second class are trained to mimic quantitatively the geometric differences between incorrectly folded models and native structures. In this paper, we focus on the relationship between energy and geometry when training the second class of knowledge-based potentials. We assume that the difference in energy between a decoy structure and the corresponding native structure is linearly related to the distance between the two structures. We trained two distance-based knowledge-based potentials accordingly, one based on all inter-residue distances (PPD), while the other had the set of all distances filtered to reflect consistency in an ensemble of decoys (PPE). We tested four types of metric to characterize the distance between the decoy and the native structure, two based on extrinsic geometry (RMSD and GTD-TS*), and two based on intrinsic geometry (Q* and MT). The corresponding eight potentials were tested on a large collection of decoy sets. We found that it is usually better to train a potential using an intrinsic distance measure. We also found that PPE outperforms PPD, emphasizing the benefits of capturing consistent information in an ensemble. The relevance of these results for the design of knowledge-based potentials is discussed.

  11. Recoil distance transmission method: Measurement of interaction cross sections of excited states with fast rare-isotope beams

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, N., E-mail: kobayashi@nscl.msu.edu [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Whitmore, K.; Iwasaki, H. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1321 (United States)

    2016-09-11

    The possible appearance of nuclear halos in ground and excited states close to the particle-decay threshold is of great importance in the investigation of nuclear structure and few-body correlations at the limit of stability. In order to obtain direct evidence of the halo structure manifested in nuclear excited states, we have considered a new method to measure the interaction cross sections of excited states. The combination of the transmission method and the recoil distance Doppler-shift method with a plunger device enables us to measure the number of interactions of the excited states in a target. Formulae to determine the interaction cross section are derived, and key issues to realize measurements are discussed. Dominant sources of errors are uncertainties in the excited-state lifetimes and γ-ray yields. We examine prototype experiments and perform simulations to study the impact of each uncertainty on the final result. This method provides a novel opportunity to perform cross section measurements on the excited states of rare isotopes.

  12. Lifetimes of states in the opposite-parity bands of 153Eu: Recoil-distance measurements following Coulomb excitation

    Science.gov (United States)

    Smith, J. F.; Simon, M. W.; Ibbotson, R. W.; Butler, P. A.; Aprahamian, A.; Bruce, A. M.; Cline, D.; Devlin, M.; Jones, G. D.; Jones, P. M.; Wu, C. Y.

    1998-12-01

    The lifetimes of 12 states in the opposite-parity bands of 153Eu have been measured using a recoil-distance technique following Coulomb excitation with a 220-MeV 58Ni beam. Electric-quadrupole (Q0) and -dipole (D0) moments, and intrinsic g factors (gK) have been extracted from the lifetimes. The Q0 and D0 values show very little dependence on spin and parity, and have the values of approximately 6.6 e b and 0.077 e fm, respectively. The gK values are found to differ for the positive- and negative-parity states. Although the large D0 values suggest a reflection-asymmetric octupole-deformed nuclear shape, the different gK values contradict this interpretation. A discussion of the nuclear structure of 153Eu in terms of potential parity-doublet bands and octupole deformation is given.

  13. Long distance free-space quantum key distribution

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt-Manderbach, T.

    2007-10-16

    The aim of the presented experiment was to investigate the feasibility of satellite-based global quantum key distribution. In this context, a free-space quantum key distribution experiment over a real distance of 144 km was performed. The transmitter and the receiver were situated in 2500 m altitude on the Canary Islands of La Palma and Tenerife, respectively. The small and compact transmitter unit generated attenuated laser pulses, that were sent to the receiver via a 15-cm optical telescope. The receiver unit for polarisation analysis and detection of the sent pulses was integrated into an existing mirror telescope designed for classical optical satellite communications. To ensure the required stability and efficiency of the optical link in the presence of atmospheric turbulence, the two telescopes were equipped with a bi-directional automatic tracking system. Still, due to stray light and high optical attenuation, secure key exchange would not be possible using attenuated pulses in connection with the standard BB84 protocol. The photon number statistics of attenuated pulses follows a Poissonian distribution. Hence, by removing a photon from all pulses containing two or more photons, an eavesdropper could measure its polarisation without disturbing the polarisation state of the remaining pulse. In this way, he can gain information about the key without introducing detectable errors. To protect against such attacks, the presented experiment employed the recently developed method of using additional 'decoy' states, i.e., the the intensity of the pulses created by the transmitter were varied in a random manner. By analysing the detection probabilities of the different pulses individually, a photon-number-splitting attack can be detected. Thanks to the decoy-state analysis, the secrecy of the resulting quantum key could be ensured despite the Poissonian nature of the emitted pulses. For a channel attenuation as high as 35 dB, a secret key rate of up to 250

  14. Backaction-driven, robust, steady-state long-distance qubit entanglement over lossy channels

    Science.gov (United States)

    Motzoi, Felix; Halperin, Eli; Wang, Xiaoting; Whaley, K. Birgitta; Schirmer, Sophie

    2016-09-01

    We present a scheme for generating robust and persistent entanglement between qubits that do not interact and that are separated by a long and lossy transmission channel, using Markovian reservoir engineering. The proposal uses only the correlated decay into the common channel of remotely separated, driven single-photon qubit transitions. This simple scheme is generic and applicable to various experimental implementations, including circuit and cavity QED, with little experimental overhead compared with methods requiring dynamic control, initialization, measurement, or feedback. In addition to avoiding these inefficiencies, the simple protocol is highly robust against noise, miscalibration, and loss in the channel. We find high-quality solutions over a wide range of parameters and show that the optimal strategy reflects a transition from ballistic to diffusive photon transmission, going from symmetrically and coherently driving a common steady state to asymmetrically absorbing photons that are emitted from one qubit by the second. Detailed analysis of the role of the transmission channel shows that allowing bidirectional decay drastically increases indistinguishability and thereby quadratically suppresses infidelity.

  15. Protein structure modelling and evaluation based on a 4-distance description of side-chain interactions

    Directory of Open Access Journals (Sweden)

    Inbar Yuval

    2010-07-01

    Full Text Available Abstract Background Accurate evaluation and modelling of residue-residue interactions within and between proteins is a key aspect of computational structure prediction including homology modelling, protein-protein docking, refinement of low-resolution structures, and computational protein design. Results Here we introduce a method for accurate protein structure modelling and evaluation based on a novel 4-distance description of residue-residue interaction geometry. Statistical 4-distance preferences were extracted from high-resolution protein structures and were used as a basis for a knowledge-based potential, called Hunter. We demonstrate that 4-distance description of side chain interactions can be used reliably to discriminate the native structure from a set of decoys. Hunter ranked the native structure as the top one in 217 out of 220 high-resolution decoy sets, in 25 out of 28 "Decoys 'R' Us" decoy sets and in 24 out of 27 high-resolution CASP7/8 decoy sets. The same concept was applied to side chain modelling in protein structures. On a set of very high-resolution protein structures the average RMSD was 1.47 Å for all residues and 0.73 Å for buried residues, which is in the range of attainable accuracy for a model. Finally, we show that Hunter performs as good or better than other top methods in homology modelling based on results from the CASP7 experiment. The supporting web site http://bioinfo.weizmann.ac.il/hunter/ was developed to enable the use of Hunter and for visualization and interactive exploration of 4-distance distributions. Conclusions Our results suggest that Hunter can be used as a tool for evaluation and for accurate modelling of residue-residue interactions in protein structures. The same methodology is applicable to other areas involving high-resolution modelling of biomolecules.

  16. Radial shock waves effectively introduced NF-kappa B decoy into rat achilles tendon cells in vitro.

    Science.gov (United States)

    Sugioka, Kaori; Nakagawa, Koichi; Murata, Ryo; Ochiai, Nobuyasu; Sasho, Takahisa; Arai, Momoko; Tsuruoka, Hiroaki; Ohtori, Seiji; Saisu, Takashi; Gemba, Takefumi; Takahashi, Kazuhisa

    2010-08-01

    The purpose of this study was to test if radial shock waves could enhance the introduction of nuclear factor-kappa B (NF-kappaB) decoy oligodeoxynucleotides, which is reported to markedly inhibit NF-kappaB activation and suppress pro-inflammatory cytokine gene expression, using rat Achilles tendon cells. In the presence of NF-kappaB decoy labeled with or without fluorescein isothiocyanate (FITC) in culture media, radial shock waves were applied to the tendon cells in variable conditions and cultivated for 24 h. The transfection rate was assessed by counting FITC-positive cells, and IL-1-induced NF-kappaB activation in the cells was assessed. Radial shock waves significantly enhanced introduction of NF-kappaB decoy-FITC into the tendon cells. IL-1-induced NF-kappaB activation was significantly inhibited by pretreatment of the cells with NF-kappaB decoy combined with radial shock wave exposure. The present study demonstrated the effectiveness of radial shock waves on introduction of NF-kappaB decoy into tendon cells. Radial shock wave treatment combined with local NF-kappaB decoy administration could be a novel therapeutic strategy for chronic tendinopathy.

  17. Associations of the decoy receptor and osteoprotegerin gene polymorphisms with ulcerative colitis in Chinese patients

    Institute of Scientific and Technical Information of China (English)

    郑香云

    2014-01-01

    Objective To investigate the correlation between decoy receptor(DcR)1,DcR2 and osteoprotegerin(OPG)gene polymorphisms with the susceptibility to ulcerative colitis(UC)in Chinese population.Methods A total of352 patients with UC as well as 463 sex-and agematched healthy controls were recruited in the study.The genetic polymorphisms of DcR1(rs12549481),DcR2(rs1133782)and OPG(rs3102735)were deter-

  18. Surveillance of influenza viruses in waterfowl used as decoys in Andalusia, Spain.

    Directory of Open Access Journals (Sweden)

    Estefanía Jurado-Tarifa

    Full Text Available A longitudinal study was carried out to determine the seroprevalence of avian influenza viruses (AIVs in waterfowl used as decoys in Andalusia, southern Spain. A total of 2319 aquatic birds from 193 flocks were analyzed before and after the hunting season 2011-2012. In the first sampling, 403 out of 2319 (18.0%, CI95%: 15.8-19.0 decoys showed antibodies against AIVs by ELISA. The AI seroprevalence was significantly higher in geese (21.0% than in ducks (11.7% (P<0.001. Besides, the spatial distribution of AIVs was not homogeneous as significant differences among regions were observed. The prevalence of antibodies against AIVs subtypes H5 and H7 were 1.1% and 0.3%, respectively, using hemagglutination inhibition test (HI. The overall and H5 seroprevalences slightly increased after the hunting period (to 19.2% and 1.4%, respectively, while the H7 seroprevalence remained at the same level (0.3%. The proportion of flocks infected by AIVs was 65.3%, while 11.2% and 4.9% of flocks were positive for H5 and H7, respectively. Viral shedding was not detected in any of the 47 samples positive by both ELISA and HI, tested by RRT-PCR. The individual incidence after the hunting season was 3.4%. The fact that 57 animals seroconverted, 15 of which were confirmed by HI (12 H5 and 3 H7, was indication of contact with AIVs during the hunting period. The results indicate that waterfowl used as decoys are frequently exposed to AIVs and may be potentially useful as sentinels for AIVs monitoring. The seroprevalence detected and the seropositivity against AIVs H5 and H7, suggest that decoys can act as reservoirs of AIVs, which may be of animal and public health concern.

  19. TRAIL Death Receptor-4, Decoy Receptor-1 and Decoy Receptor-2 Expression on CD8+ T Cells Correlate with the Disease Severity in Patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Bisgin Atil

    2010-08-01

    Full Text Available Abstract Background Rheumatoid Arthritis (RA is a chronic autoimmune inflammatory disorder. Although the pathogenesis of disease is unclear, it is well known that T cells play a major role in both development and perpetuation of RA through activating macrophages and B cells. Since the lack of TNF-Related Apoptosis Inducing Ligand (TRAIL expression resulted in defective thymocyte apoptosis leading to an autoimmune disease, we explored evidence for alterations in TRAIL/TRAIL receptor expression on peripheral T lymphocytes in the molecular mechanism of RA development. Methods The expression of TRAIL/TRAIL receptors on T cells in 20 RA patients and 12 control individuals were analyzed using flow cytometry. The correlation of TRAIL and its receptor expression profile was compared with clinical RA parameters (RA activity scored as per DAS28 using Spearman Rho Analysis. Results While no change was detected in the ratio of CD4+ to CD8+ T cells between controls and RA patient groups, upregulation of TRAIL and its receptors (both death and decoy was detected on both CD4+ and CD8+ T cells in RA patients compared to control individuals. Death Receptor-4 (DR4 and the decoy receptors DcR1 and DcR2 on CD8+ T cells, but not on CD4+ T cells, were positively correlated with patients' DAS scores. Conclusions Our data suggest that TRAIL/TRAIL receptor expression profiles on T cells might be important in revelation of RA pathogenesis.

  20. Double-stranded RNA transcribed from vector-based oligodeoxynucleotide acts as transcription factor decoy

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xiao [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Gang, Yi [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi’an 710038, Shaanxi Province (China); Wang, Honghong [No. 518 Hospital of Chinese People’s Liberation Army, Xi’an 710043, Shaanxi Province (China); Wang, Jiayin [The Genome Institute, Washington University in St. Louis, St. Louis, MO 63108 (United States); Zhao, Lina [Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Xu, Li, E-mail: lxuhelen@163.com [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Liu, Zhiguo, E-mail: liuzhiguo@fmmu.edu.cn [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China)

    2015-02-06

    Highlights: • A shRNA vector based transcription factor decoy, VB-ODN, was designed. • VB-ODN for NF-κB inhibited cell viability in HEK293 cells. • VB-ODN inhibited expression of downstream genes of target transcription factors. • VB-ODN may enhance nuclear entry ratio for its feasibility of virus production. - Abstract: In this study, we designed a short hairpin RNA vector-based oligodeoxynucleotide (VB-ODN) carrying transcription factor (TF) consensus sequence which could function as a decoy to block TF activity. Specifically, VB-ODN for Nuclear factor-κB (NF-κB) could inhibit cell viability and decrease downstream gene expression in HEK293 cells without affecting expression of NF-κB itself. The specific binding between VB-ODN produced double-stranded RNA and NF-κB was evidenced by electrophoretic mobility shift assay. Moreover, similar VB-ODNs designed for three other TFs also inhibit their downstream gene expression but not that of themselves. Our study provides a new design of decoy for blocking TF activity.

  1. Decoy cells in the urine cytology of a renal transplant recipient: An immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Pillai K

    2010-04-01

    Full Text Available Human polyoma virus causes renal dysfunction and graft loss as a result of tubulo-interstial nephritis in renal transplant recipients after reactivation of latent virus in renal epithelium. The infected cells in the urinary sediments are characterized by large homogenous inclusions, which may cause diagnostic error in urine cytology. The epithelial cells with polyoma viral inclusions in urine cytology specimens are termed Decoy cells to caution pathologists not to misdiagnose these cells as cancer cells. We present a case of polyoma viral changes detected the first time in our laboratory in the urine of a 46year old male who underwent renal transplantation six months back and followed by immunotherapy. Urine cytological examination showed decoy cells and subsequently revealed on histopathology. Immunoperoxidase staining for SV-40 LT antigen (LT ag, expression of proliferating cell nuclear antigen (PCNA, p53 and Rb genes were also studied in the tissue sections for further observation. The expression of SV40 LT ag was negative, while PCNA showed strong positivity; p53 and Rb were expressed moderately in the nuclei of cells in the tubules. The report of a case of decoy cells in the urine of a patient with renal transplantation focuses the importance of cytologic analysis of urine as a diagnostic tool for screening renal transplant recipients at risk of polyoma viral infection.

  2. Decoy cells in the urine cytology of a renal transplant recipient: an immunohistochemical study.

    Science.gov (United States)

    Pillai, K Raveendran; Jayasree, K; Pisharody, Ramdas; Abraham, Elizabeth K

    2010-01-01

    Human polyoma virus causes renal dysfunction and graft loss as a result of tubulo-interstial nephritis in renal transplant recipients after reactivation of latent virus in renal epithelium. The infected cells in the urinary sediments are characterized by large homogenous inclusions, which may cause diagnostic error in urine cytology. The epithelial cells with polyoma viral inclusions in urine cytology specimens are termed Decoy cells to caution pathologists not to misdiagnose these cells as cancer cells. We present a case of polyoma viral changes detected the first time in our laboratory in the urine of a 46year old male who underwent renal transplantation six months back and followed by immunotherapy. Urine cytological examination showed decoy cells and subsequently revealed on histopathology. Immunoperoxidase staining for SV-40 LT antigen (LT ag), expression of proliferating cell nuclear antigen (PCNA), p53 and Rb genes were also studied in the tissue sections for further observation. The expression of SV40 LT ag was negative, while PCNA showed strong positivity; p53 and Rb were expressed moderately in the nuclei of cells in the tubules. The report of a case of decoy cells in the urine of a patient with renal transplantation focuses the importance of cytologic analysis of urine as a diagnostic tool for screening renal transplant recipients at risk of polyoma viral infection.

  3. Toll-like receptor 4 decoy, TOY, attenuates gram-negative bacterial sepsis.

    Science.gov (United States)

    Jung, Keehoon; Lee, Jung-Eun; Kim, Hak-Zoo; Kim, Ho Min; Park, Beom Seok; Hwang, Seong-Ik; Lee, Jie-Oh; Kim, Sun Chang; Koh, Gou Young

    2009-10-09

    Lipopolysaccharide (LPS), the Gram-negative bacterial outer membrane glycolipid, induces sepsis through its interaction with myeloid differentiation protein-2 (MD-2) and Toll-like receptor 4 (TLR4). To block interaction between LPS/MD-2 complex and TLR4, we designed and generated soluble fusion proteins capable of binding MD-2, dubbed TLR4 decoy receptor (TOY) using 'the Hybrid leucine-rich repeats (LRR) technique'. TOY contains the MD-2 binding ectodomain of TLR4, the LRR motif of hagfish variable lymphocyte receptor (VLR), and the Fc domain of IgG1 to make it soluble, productive, and functional. TOY exhibited strong binding to MD-2, but not to the extracellular matrix (ECM), resulting in a favorable pharmacokinetic profile in vivo. TOY significantly extended the lifespan, when administered in either preventive or therapeutic manners, in both the LPS- and cecal ligation/puncture-induced sepsis models in mice. TOY markedly attenuated LPS-triggered NF-kappaB activation, secretion of proinflammatory cytokines, and thrombus formation in multiple organs. Taken together, the targeting strategy for sequestration of LPS/MD-2 complex using the decoy receptor TOY is effective in treating LPS- and bacteria-induced sepsis; furthermore, the strategy used in TOY development can be applied to the generation of other novel decoy receptor proteins.

  4. Regenerated silk fibers: Structural studies and solid state NMR techniques for efficient multiple distance determinations in proteins

    Science.gov (United States)

    Liivak, Oskar

    2000-09-01

    Material Science is the science of understanding the relationship between the molecular level structure of a material and its macroscopic properties. Such research requires both the ability to determine molecular structure and the ability to control and modify the molecular structure. The present research into silks, especially the dragline silk from the spider Nephila clavipes , is occurring at a time when these two criteria are beginning to be met for proteins like spider silk. Genetic engineering has evolved to the point where material scientists have full control over the primary sequence of amino acids that comprise proteins. In addition, solid state nuclear magnetic resonance (NMR) techniques exist which allow us to probe molecular structure. This work applies solid state NMR to the study of the structure of silk fibers. In particular, we focus on techniques of fiber regeneration from solution. The purpose is not only to develop the techniques by which genetically engineered fibers could be spun into fibers for mass production but also as a tool into fundamental silk research. Results on these regenerated fibers show a correlation between the fraction of the silk's alanine residues which are in the β-sheet conformation and the ultimate tensile strength of the fibers. In addition, in a clever mating of the fiber regeneration technique and the solid state NMR distance measurement experiment, rotational echo double resonance (REDOR), we investigate the supramolecular topology of the alanine β-sheet crystals. Even though the REDOR technique has failings for the complicated ISn spin systems found in the silk samples, a qualitative analysis does indicate that the β-sheet crystals are intermolecular. Finally, we investigate a new class of REDOR-like experiments which are designed to overcome the failings of REDOR in ISn spin systems. Experimental data is shown to validate these ideas. An alternate pulse sequence is also introduced and verified with experimental

  5. High Efficient Quantum Key Distribution by Random Using Classified Signal Coherent States

    Institute of Scientific and Technical Information of China (English)

    XI Jing-Bo; FANG Xi-Ming

    2006-01-01

    The decoy-state method is a useful method in resisting the attacks on quantum key distribution. However, how to choose the intensities of decoy states and the ratio of the decoy states and the signal state is still an open question. We present a simple formula to analyse the problem. We also give a simple method to derive the bounds of the necessary counting rates and quantum bit error rates for BB84 and SARG04; the latter was previously proposed by Scarani et al. [Phys. Rev. Lett. 92 (2004) 057901] We then propose a multi-signal-state method which employs different coherent states either as the decoy state or as the signal state to carry out quantum key distribution. We find our protocol more efficient and feasible.

  6. Valuation of travel time for international long-distance travel - results from the Fehmarn Belt stated choice experiment

    DEFF Research Database (Denmark)

    Mabit, Stefan Lindhard; Rich, Jeppe; Burge, Peter

    2013-01-01

    significant interactions among travel cost and time, and journey characteristics, such as distance and duration. This had direct impact on the VTTS, which was shown to decrease with distance and duration. Thirdly, we found that air travel implies a higher average VTTS, which is to be expected but rarely......The geographical scope of travel varies from short distances in urban areas to long distances across cities and countries. While urban travel has been widely analysed in the literature, travel over longer distances and particularly across countries, has received much less attention. While this may...... be justified due to the number of travellers it cannot be justified when looking at the mileage consumption and its resulting environmental impacts. In this paper, we investigate international long-distance travel preferences related to travel between Scandinavia and Central Europe with particular focus...

  7. Nuclear factor-κB decoy oligodeoxynucleotides attenuates ischemia/reperfusion injury in rat liver graft

    Institute of Scientific and Technical Information of China (English)

    Ming-Qing Xu; Xiu-Rong Shuai; Mao-Lin Yan; Ming-Man Zhang; Lu-Nan Yan

    2005-01-01

    AIM: To evaluate the protective effect of NF-κB decoy oligodeoxynucleotides (ODNs) on ischemia/reperfusion (I/R) injury in rat liver graft.METHODS: Orthotopic syngeneic rat liver transplantation was performed with 3 h of cold preservation of liver graft in University of Wisconsin solution containing phosphorothioated double-stranded NF-κB decoy ODNs or scrambled ODNs. NF-κB decoy ODNs or scrambled ODNs were injected intravenously into donor and recipient rats 6 and 1 h before operation,respectively. Recipients were killed 0 to 16 h after liver graft reperfusion. NF-κB activity in the liver graft was analyzed by electrophoretic mobility shift assay (EMSA). Hepatic mRNA expression of TNF-α, IFN-γand intercellular adhesion molecule-1 (ICAM-1) were determined by semiquantitative RT-PCR. Serum levels of TNF-α and IFN-γ were measured by enzyme-linked immunosorbent assays (ELISA). Serum level of alanine transaminase (ALT) was measured using a diagnostic kit. Liver graft myeloperoxidase (MPO) content was assessed.RESULTS: NF-κB activation in liver graft was induced in a time-dependent manner, and NF-κB remained activated for 16 h after graft reperfusion. NF-κB activation in liver graft was significant at 2 to 8 h and slightly decreased at 16 h after graft reperfusion. Administration of NF-κB decoy ODNs significantly suppressed NF-κB activation as well as mRNA expression of TNF-α, IFN-γ and ICAM-1 in the liver graft. The hepatic NF-κB DNA binding activity [presented as integral optical density (IOD) value] in the NF-κB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (2.16±0.78 vs 36.78±6.35 and 3.06±0.84 vs 47.62± 8.71 for IOD value after 4 and 8 h of reperfusion, respectively, P<0.001).The hepatic mRNA expression level of TNF-α, IFN-y and ICAM-1 [presented as percent of β-actin mRNA(%)] in the NF-κBdecoy ODNs treatment group rat was significantly lower than that of the I/R group rat (8.31 ±3.48 vs 46.37±10

  8. Distance dependence of intrahelix Ru(II)* to Os(II) polypyridyl excited-state energy transfer in oligoproline assemblies.

    Science.gov (United States)

    Brennaman, M Kyle; Fleming, Cavan N; Slate, Cheryl A; Serron, Scafford A; Bettis, Stephanie E; Erickson, Bruce W; Papanikolas, John M; Meyer, Thomas J

    2013-05-30

    Energy transfer between the metal-to-ligand charge transfer (MLCT) excited states of [Pra [M(II)(bpy)2(4-Me-4'(-N(H)CO)bpy)](PF6)2 units ([Pra(M(II)bpy2(mbpy)](2+): M(II) = Ru(II) or Os(II), bpy = 2,2'-bipyridine, mbpy = 4'-methyl-2,2'-bipyridine-4-carboxamido, Pra = 4-M(II)-L-proline) linked covalently to oligoproline assemblies in room temperature acetonitrile occurs on the picosecond-nanosecond time scale and has been time-resolved by transient emission measurements. Three derivatized oligoprolines, [CH3-CO-Pro6-Pra[Os(II)(bpy)2(mbpy)](2+)-Pro2-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro2-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro6-Glu-NH2](6+) (ORR-2, Pro = L-proline and Glu = glutamic acid); [CH3-CO-Pro6-Pra[Os(II)(bpy)2(mbpy)](2+)-Pro3-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro3-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro6-Glu-NH2](6+) (ORR-3); and CH3-CO-Pro6-Pra[Os(II)(bpy)2(mbpy)](2+)-Pro5-Pra[Ru(II)(bpy)2(mbpy)](2+)-Pro5-Pra[Ru(II)(bpy)2(mbpy)](2+)Pro6-Glu2-NH2](6+) (ORR-5), were prepared by using solid-phase peptide synthesis. Given the helical nature of the resulting assemblies and the nature of the synthesis, composition, length, and loading pattern are precisely controlled in the assemblies. In acetonitrile, they adopt a proline I helical secondary structure, confirmed by circular dichroism, in which the appended chromophores are ordered in well-defined orientations and internuclear separation distances although helix formation for ORR-2 is incomplete. Quantitative comparison of oligoproline ground-state absorption and steady-state emission spectra to those for the constituents, [Boc-Pra[M(II)(bpy)2(mbpy)](2+)-OH](PF6)2 (Boc = N(α)-(1,1-dimethylethoxycarbonyl), shows that following Ru(II) light absorption, Ru(II)* undergoes facile energy transfer resulting in sensitization of Os(II). Sensitization efficiencies are 93% for ORR-2, 77% for ORR-3, and 73% for ORR-5. Picosecond-resolved emission measurements reveal complex, coupled dynamics that arise from excited-state decay and kinetically

  9. Measurement device-independent quantum key distribution with heralded pair coherent state

    Science.gov (United States)

    Chen, Dong; Shang-Hong, Zhao; Lei, Shi

    2016-10-01

    The original measurement device-independent quantum key distribution is reviewed, and a modified protocol using heralded pair coherent state (HPCS) is proposed to overcome the quantum bit error rate associated with the dark count rate of the detectors in long-distance quantum key distribution. Our simulation indicates that the secure transmission distance can be improved evidently with HPCS owing to the lower probability of vacuum events when compared with weak coherent source scenario, while the secure key rate can be increased with HPCS due to the higher probability of single-photon events when compared with heralded single-photon source scenario. Furthermore, we apply the finite key analysis to the decoy state MDI-QKD with HPCS and obtain a practical key rate.

  10. What Is the Role of Distance Learning in the State University System? Information Brief. Volume 6, Issue 2

    Science.gov (United States)

    Florida Board of Governors, State University System, 2008

    2008-01-01

    Distance learning is the term used when the delivery of instruction involves the separation of student(s) and the instructor by time and/or space. Some forms of distance learning include correspondence, telecourses, online instruction, computer assisted instruction, and instructional delivery that relies upon satellite, cable, broadcast (TV or…

  11. Ab initio MO study on equilibrium bond distance between Fe and pyridine in bis(pyridine)(porphinato) iron for various electronic states

    Science.gov (United States)

    Saito, Minoru; Kashiwagi, Hiroshi

    1985-04-01

    For bis(pyridine)(porphinato) iron [FeP(py)2], a correlation between the iron electronic state and the equilibrium Fe-Npy distance was investigated. Potential energy curves as a function of the Fe-Npy distance were calculated for low-spin, intermediate-spin, and high-spin states of the ferric and ferrous ions by the ab initio SCF MO method. The equilibrium Fe-Npy distances were obtained from the potential curves. The values obtained for the ferric low-spin and high-spin states were in good agreement with the experimental values for Fe(III)(OEP)(3-Clpy)2 within the differences, ±0.05 Å. The following significant features were found. The equilibrium distance is elongated by the occupation of the 3dz2 orbital and is shortened by the oxidation of the iron atom. The distance and the force constant for the symmetrical py-Fe-py stretching are strongly correlated with the overlap population between the 3dz2 orbital and pyridine-nitrogen orbitals.

  12. On the importance of the distance measures used to train and test knowledge-based potentials for proteins

    DEFF Research Database (Denmark)

    Carlsen, Martin; Koehl, Patrice; Røgen, Peter

    2014-01-01

    protein structures into energy values, while potentials from the second class are trained to mimic quantitatively the geometric differences between incorrectly folded models and native structures. In this paper, we focus on the relationship between energy and geometry when training the second class...... of knowledge-based potentials. We assume that the difference in energy between a decoy structure and the corresponding native structure is linearly related to the distance between the two structures. We trained two distance-based knowledge-based potentials accordingly, one based on all inter-residue distances...... geometry (Q* and MT). The corresponding eight potentials were tested on a large collection of decoy sets. We found that it is usually better to train a potential using an intrinsic distance measure. We also found that PPE outperforms PPD, emphasizing the benefits of capturing consistent information...

  13. Target-Decoy Approach and False Discovery Rate: When Things May Go Wrong

    OpenAIRE

    Gupta, Nitin; Bandeira, Nuno; Keich, Uri; Pevzner, Pavel A.

    2011-01-01

    The target-decoy approach (TDA) has done the field of proteomics a great service by filling in the need to estimate the false discovery rates (FDR) of peptide identifications. While TDA is often viewed as a universal solution to the problem of FDR evaluation, we argue that the time has come to critically re-examine TDA and to acknowledge not only its merits but also its demerits. We demonstrate that some popular MS/MS search tools are not TDA-compliant and that it is easy to develop a non-TDA...

  14. Toll-Like Receptor 4 Decoy, TOY, Attenuates Gram-Negative Bacterial Sepsis

    OpenAIRE

    Keehoon Jung; Jung-Eun Lee; Hak-Zoo Kim; Ho Min Kim; Beom Seok Park; Seong-Ik Hwang; Jie-Oh Lee; Sun Chang Kim; Gou Young Koh

    2009-01-01

    Lipopolysaccharide (LPS), the Gram-negative bacterial outer membrane glycolipid, induces sepsis through its interaction with myeloid differentiation protein-2 (MD-2) and Toll-like receptor 4 (TLR4). To block interaction between LPS/MD-2 complex and TLR4, we designed and generated soluble fusion proteins capable of binding MD-2, dubbed TLR4 decoy receptor (TOY) using 'the Hybrid leucine-rich repeats (LRR) technique'. TOY contains the MD-2 binding ectodomain of TLR4, the LRR motif of hagfish va...

  15. Aptamer-Mediated Codelivery of Doxorubicin and NF-κB Decoy Enhances Chemosensitivity of Pancreatic Tumor Cells

    Directory of Open Access Journals (Sweden)

    David Porciani

    2015-01-01

    Full Text Available Aptamers able to bind efficiently cell-surface receptors differentially expressed in tumor and in healthy cells are emerging as powerful tools to perform targeted anticancer therapy. Here, we present a novel oligonucleotide chimera, composed by an RNA aptamer and a DNA decoy. Our assembly is able to (i target tumor cells via an antitransferrin receptor RNA aptamer and (ii perform selective codelivery of a chemotherapeutic drug (Doxorubicin and of an inhibitor of a cell-survival factor, the nuclear factor κB decoy oligonucleotide. Both payloads are released under conditions found in endolysosomal compartments (low pH and reductive environment. Targeting and cytotoxicity of the oligonucleotidic chimera were assessed by confocal microscopy, cell viability, and Western blot analysis. These data indicated that the nuclear factor κB decoy does inhibit nuclear factor κB activity and ultimately leads to an increased therapeutic efficacy of Doxorubicin selectively in tumor cells.

  16. Research for visualization of running state of long-distance water transmission pipeline based on OpenGL

    Science.gov (United States)

    Zhang, Xiaoping; Xu, Xuejun; Liu, Bing; Zhang, Zhendong

    2017-03-01

    The running condition of long distance water pipeline are complicated and changeable, and the lag of water flow is obvious, which is the key technical problem to be solved in the process of regulation and control. According to the present situation of the long-distance water conveyance project, the visualization simulation technology is used to study the operation and management of the long-distance water conveyance pipeline based on OpenGL technology. The system developed in this paper can combine pipeline information, working condition data and relevant data to provide a visualization platform for analysis and decision-making of project management and operation.

  17. Alabama's Education Coalition Focuses on Supporting the State's Math, Science and Technology Initiative and on Building Distance Learning Programs

    Science.gov (United States)

    Denson, R. L.

    2003-12-01

    The Alabama Math Science Technology Educational Coalition (AMSTEC) was formed as a non-profit after a 1998 NASA Linking Leaders program brought in education and corporate leaders to address systemic education reform in Alabama public schools. AMSTEC was instrumental in the creation of the Alabama Math Science Technology Initiative (AMSTI), a K-12 program designed using data from national and international research and local teacher survey. In the face of dwindling government support in a state ranked last in education funding, AMSTEC believes that its best hope for improved STEM education lies in strengthening its community/industry partnerships and building upon the Department of Education's newly created AMSTI program. NASA's GLOBE program is the primary earth science education component being integrated into AMSTI. AMSTI is structured to provide teachers with (1) the materials, equipment, technology and supplies necessary to deliver high quality, inquiry-based instruction; (2) professional development linked directly to the educational resources with the intent of strengthening content knowledge, instructional strategies, and use of assessment tools; and (3) on-site support and mentoring throughout the year in the interest of achieving these goals. Roles for community partners to support these objectives far exceed that of mere funding - especially in the area of mentoring and professional development. Currently, AMSTEC consists of 100+ members including classroom teachers and district officers, education department representatives from higher educational institutions, policy makers and administrators, and government and industry representatives. AMSTEC remains partially tied to NASA fiscally and is administratively housed by the National Space Science and Technology Center's Earth System Science Center. AMSTEC's partnership emphasis is focused on increasing corporate and industry participation to support the implementation of AMSTI and its hub

  18. The Effects of Experimentally Induced Rumination, Positive Reappraisal, Acceptance, and Distancing when Thinking about a Stressful Event on Affect States in Adolescents

    Science.gov (United States)

    Rood, Lea; Roelofs, Jeffrey; Bogels, Susan M.; Arntz, Arnoud

    2012-01-01

    The current study compares the effects of experimentally induced rumination, positive reappraisal, distancing, and acceptance on affect states in adolescents aged 13-18. Participants (N = 160) were instructed to think about a recent stressful event. Next, they received specific instructions on how to think about that event in each condition.…

  19. Distance Learning

    Science.gov (United States)

    1997-12-01

    A study reviewing the existing Army Distance Learning Plan (ADLP) and current Distance Learning practices, with a focus on the Army’s training and...educational challenges and the benefits of applying Distance Learning techniques. The ASB study panel makes six specific recommendations, the most

  20. Optimal visual simulation of the self-tracking combustion of the infrared decoy based on the particle system

    Science.gov (United States)

    Hu, Qi; Duan, Jin; Wang, LiNing; Zhai, Di

    2016-09-01

    The high-efficiency simulation test of military weapons has a very important effect on the high cost of the actual combat test and the very demanding operational efficiency. Especially among the simulative emulation methods of the explosive smoke, the simulation method based on the particle system has generated much attention. In order to further improve the traditional simulative emulation degree of the movement process of the infrared decoy during the real combustion cycle, this paper, adopting the virtual simulation platform of OpenGL and Vega Prime and according to their own radiation characteristics and the aerodynamic characteristics of the infrared decoy, has simulated the dynamic fuzzy characteristics of the infrared decoy during the real combustion cycle by using particle system based on the double depth peeling algorithm and has solved key issues such as the interface, coordinate conversion and the retention and recovery of the Vega Prime's status. The simulation experiment has basically reached the expected improvement purpose, effectively improved the simulation fidelity and provided theoretical support for improving the performance of the infrared decoy.

  1. "I can do perfectly well without a car!": An exploration of stated preferences for middle-distance travel

    NARCIS (Netherlands)

    N.J.A. van Exel (Job); G. de Graaf; P. Rietveld (Piet)

    2011-01-01

    textabstractThis article presents the results of a study exploring travellers' preferences for middle-distance travel using Q-methodology. Respondents rank-ordered 42 opinion statements regarding travel choice and motivations for travel in general and for car and public transport as alternative

  2. On the importance of the distance measures used to train and test knowledge-based potentials for proteins.

    Directory of Open Access Journals (Sweden)

    Martin Carlsen

    Full Text Available Knowledge-based potentials are energy functions derived from the analysis of databases of protein structures and sequences. They can be divided into two classes. Potentials from the first class are based on a direct conversion of the distributions of some geometric properties observed in native protein structures into energy values, while potentials from the second class are trained to mimic quantitatively the geometric differences between incorrectly folded models and native structures. In this paper, we focus on the relationship between energy and geometry when training the second class of knowledge-based potentials. We assume that the difference in energy between a decoy structure and the corresponding native structure is linearly related to the distance between the two structures. We trained two distance-based knowledge-based potentials accordingly, one based on all inter-residue distances (PPD, while the other had the set of all distances filtered to reflect consistency in an ensemble of decoys (PPE. We tested four types of metric to characterize the distance between the decoy and the native structure, two based on extrinsic geometry (RMSD and GTD-TS*, and two based on intrinsic geometry (Q* and MT. The corresponding eight potentials were tested on a large collection of decoy sets. We found that it is usually better to train a potential using an intrinsic distance measure. We also found that PPE outperforms PPD, emphasizing the benefits of capturing consistent information in an ensemble. The relevance of these results for the design of knowledge-based potentials is discussed.

  3. Information Distance

    CERN Document Server

    Bennett, Charles H; Li, Ming; Vitanyi, Paul M B; Zurek, Wojciech H

    2010-01-01

    While Kolmogorov complexity is the accepted absolute measure of information content in an individual finite object, a similarly absolute notion is needed for the information distance between two individual objects, for example, two pictures. We give several natural definitions of a universal information metric, based on length of shortest programs for either ordinary computations or reversible (dissipationless) computations. It turns out that these definitions are equivalent up to an additive logarithmic term. We show that the information distance is a universal cognitive similarity distance. We investigate the maximal correlation of the shortest programs involved, the maximal uncorrelation of programs (a generalization of the Slepian-Wolf theorem of classical information theory), and the density properties of the discrete metric spaces induced by the information distances. A related distance measures the amount of nonreversibility of a computation. Using the physical theory of reversible computation, we give...

  4. Tunable Excited-State Properties and Dynamics as a Function of Pt–Pt Distance in Pyrazolate-Bridged Pt(II) Dimers

    Energy Technology Data Exchange (ETDEWEB)

    Brown-Xu, Samantha E.; Kelley, Matthew S. J.; Fransted, Kelly A.; Chakraborty, Arnab; Schatz, George C.; Castellano, Felix N.; Chen, Lin X.

    2016-02-04

    The influence of molecular structure on excited state properties and dynamics of a series of cyclometalated platinum dimers was investigated through a combined experimental and theoretical approach using femtosecond transient absorption (fs TA) spectroscopy and density functional theory (DFT) calculations. The molecules have the general formula [Pt(ppy)(µ-R2pz)]2 where ppy = 2-phenylpyridine, pz = pyrazolate and R = H, Me, Ph, or tBu, and are strongly photoluminescent at room temperature. The distance between the platinum centers in this A frame geometry can be varied depending on the steric bulk of the bridging pyrazolate ligands that exert structural constraints and compress the Pt-Pt distance. At large Pt-Pt distances there is little interaction between the subunits and the chromophore behaves similar to a monomer with excited states described as mixtures of ligand-centered and metal-to-ligand charge transfer (LC/MLCT) transitions. When the Pt(II) centers are brought closer together with bulky bridging ligands, they interact through their orbitals and the S1 and T1 states are best characterized as metal metal to ligand charge transfer (MMLCT) in character. The results of the fs TA experiments reveal that intersystem crossing (ISC) occurs on ultrafast timescales (τS1 < 200 fs) while there are two relaxation processes occurring within the triplet manifold, τ1 = 0.5 – 3.2 ps and τ2 = 20 – 70 ps; the longer time constants correspond to the presence of bulkier bridging ligands. DFT calculations illustrate that the Pt-Pt distances further contract in the T1 3MMLCT states, therefore slower relaxation may be related to a larger structural reorganization. Subsequent investigations using faster time resolution are planned to measure the ISC process as well as to identify any potential coherent interaction(s) between the platinum centers that may occur.

  5. Expression and regulation of the decoy bone morphogenetic protein receptor BAMBI in the developing avian face.

    Science.gov (United States)

    Higashihori, Norihisa; Song, Yiping; Richman, Joy M

    2008-05-01

    Here, we examine the expression and regulation of the gene BAMBI, a kinase-deficient decoy receptor capable of interacting with type I bone morphogenetic protein (BMP) receptors in avian embryos. Initially, expression was limited to the endoderm during neurula and pharyngula stages. From embryonic day 3.5 (stage 20) and onward, BAMBI expression almost perfectly overlapped with known expression patterns for BMP4, particularly in the face and limbs. We performed bead implant experiments in the face to see which signals could be repressing or promoting expression of BAMBI. Our data point to retinoids and BMPs as being major positive regulators of BAMBI expression; however, fibroblast growth factor 2 acts to repress BAMBI. Furthermore, retinoic acid is likely to act directly on BAMBI as induction occurs in the presence of cycloheximide. The data suggested that BAMBI could be used to regulate Bmp signaling during tissue interactions that are an integral part of facial morphogenesis.

  6. Sharks shape the geometry of a selfish seal herd: experimental evidence from seal decoys.

    Science.gov (United States)

    De Vos, Alta; O'Riain, M Justin

    2010-02-23

    Many animals respond to predation risk by forming groups. Evolutionary explanations for group formation in previously ungrouped, but loosely associated prey have typically evoked the selfish herd hypothesis. However, despite over 600 studies across a diverse array of taxa, the critical assumptions of this hypothesis have remained collectively untested, owing to several confounding problems in real predator-prey systems. To solve this, we manipulated the domains of danger of Cape fur seal (Arctocephalus pusillus pusillus) decoys to provide evidence that a selfish reduction in a seals' domain of danger results in a proportional reduction in its predation risk from ambush shark attacks. This behaviour confers a survival advantage to individual seals within a group and explains the evolution of selfish herds in a prey species. These findings empirically elevate Hamilton's selfish herd hypothesis to more than a 'theoretical curiosity'.

  7. Constraining distance and inclination angle of V4641 Sgr using ${\\it SWIFT}$ and ${\\it NuSTAR}$ observations during low soft spectral state

    CERN Document Server

    Pahari, Mayukh; Dewangan, Gulab C; Pawar, Pramod

    2015-01-01

    We present results from ${\\it NuSTAR}$ and ${\\it SWIFT}$/XRT joint spectral analysis of V4641 Sgr during a disk dominated or soft state as well as a powerlaw dominated or hard state. The soft state spectrum is well modeled by a relativistically blurred disk emission, a powerlaw, a broad Iron line, two narrow emission lines and two edges. The Markov Chain Monte Carlo simulation technique and the relativistic effects seen in the disk and broad Iron line allow us to self-consistently constrain the inner disk radius, disk inclination angle and distance to the source at 2.43$^{+0.39}_{-0.17}$ R$_g$ (GM/c$^2$), 69.5$^{+12.8}_{-4.2}$ degrees and 10.8$^{+1.6}_{-2.5}$ kpc respectively. For the hard state, the spectrum is a power-law with a weakly broad Iron line and an edge. The distance estimate gives a measure of the Eddington fraction, $L_{2.0 - 80.0 keV}/L_{Edd}$, to be $\\sim$1.3 $\\times$ 10$^{-2}$ and $\\sim$1.9 $\\times$ 10$^{-3}$ for the soft and hard states respectively. Unlike many other typical black hole syst...

  8. Modeling, Simulation, and Analysis of a Decoy State Enabled Quantum Key Distribution System

    Science.gov (United States)

    2015-03-26

    needs and required functionality early in the development cycle, documenting requirements, then proceeding with design synthesis and system validation...is an open source IDE that supports software project development in Java, C, C++, PHP , and other languages. The Eclipse IDE supports version

  9. Nuclear factor-kappa B decoy suppresses nerve injury and improves mechanical allodynia and thermal hyperalgesia in a rat lumbar disc herniation model.

    Science.gov (United States)

    Suzuki, Munetaka; Inoue, Gen; Gemba, Takefumi; Watanabe, Tomoko; Ito, Toshinori; Koshi, Takana; Yamauchi, Kazuyo; Yamashita, Masaomi; Orita, Sumihisa; Eguchi, Yawara; Ochiai, Nobuyasu; Kishida, Shunji; Takaso, Masashi; Aoki, Yasuchika; Takahashi, Kazuhisa; Ohtori, Seiji

    2009-07-01

    Nuclear factor-kappa B (NF-kappaB) is a gene transcriptional regulator of inflammatory cytokines. We investigated the transduction efficiency of NF-kappaB decoy to dorsal root ganglion (DRG), as well as the decrease in nerve injury, mechanical allodynia, and thermal hyperalgesia in a rat lumbar disc herniation model. Forty rats were used in this study. NF-kappaB decoy-fluorescein isothiocyanate (FITC) was injected intrathecally at the L5 level in five rats, and its transduction efficiency into DRG measured. In another 30 rats, mechanical pressure was placed on the DRG at the L5 level and nucleus pulposus harvested from the rat coccygeal disc was transplanted on the DRG. Rats were classified into three groups of ten animals each: a herniation + decoy group, a herniation + oligo group, and a herniation only group. For behavioral testing, mechanical allodynia and thermal hyperalgesia were evaluated. In 15 of the herniation rats, their left L5 DRGs were resected, and the expression of activating transcription factor 3 (ATF-3) and calcitonin gene-related peptide (CGRP) was evaluated immunohistochemically compared to five controls. The total transduction efficiency of NF-kappaB decoy-FITC in DRG neurons was 10.8% in vivo. The expression of CGRP and ATF-3 was significantly lower in the herniation + decoy group than in the other herniation groups. Mechanical allodynia and thermal hyperalgesia were significantly suppressed in the herniation + decoy group. NF-kappaB decoy was transduced into DRGs in vivo. NF-kappaB decoy may be useful as a target for clarifying the mechanism of sciatica caused by lumbar disc herniation.

  10. Solar short-distance heat. State of projects in Germany; Solare Nahwaerme. Stand der Projekte in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Fisch, M.N. [Technische Univ. Braunschweig (Germany). Inst. fuer Gebaeude- und Solartechnik, Inter-Governmental Maritime Consultative Organization, Steinbeis Transferzentrum Energie-, Gebaeude- und Solartechnik (STZ-EGS), Stuttgart (Germany)

    1999-10-01

    After the successful testing of smaller solar-assisted short-distance heat projects during the first half of the 90s in Germany (e.g., Ravensburg, Koengen, Neckarsulm, Schwaebisch-Gmuend), the first large-scale solar plants with long-term thermal energy stores went operational in Hamburg and Friedrichshafen in late 1996. So, a goal was attained that had seemed Utopian for many years: to heat buildings in winter with solar energy stored during summer. (orig.) [Deutsch] Nach der erfolgreichen Erprobung von kleineren solarunterstuetzten Nahwaermeprojekten in der ersten Haelfte der neunziger Jahre in Deutschland (z.B. Ravensburg, Koengen, Neckarsulm, Schwaebisch-Gmuend) gingen Ende 1996 in Hamburg und Friedrichshafen die ersten solaren Grossanlagen mit Langzeit-Waermespeicher in Betrieb. Damit wurde ein Ziel erreicht, das ueber viele Jahre hinweg utopisch erschienen war - mit der Sonnenenergie aus dem Sommer im Winter die Gebaeude zu beheizen. (orig.)

  11. Up-regulation of NKX3.1 Expression and Inhibition of LNCaP Cell Proliferation Induced by an Inhibitory Element Decoy

    Institute of Scientific and Technical Information of China (English)

    An-Li JIANG; Xiao-Yan HU; Peng-Ju ZHANG; Mei-Lan HE; Feng KONG; Zhi-Fang LIU; Hui-Qing YUAN; Jian-Ye ZHANG

    2005-01-01

    NKX3.1 is an androgen-regulated prostate-specific homeobox gene that is thought to play an important role in prostate development and cancerogenesis. NKX3.1 acts as a tumor suppressor gene specifically in the prostate. Up-regulation of NKX3.1 gene offers a promising gene therapy for prostate cancer. The decoy strategy has been developed and is considered a useful tool for regulating gene expression and gene therapy. In our previous studies, we identified a 20 bp inhibitory element upstream of the NKX3.1 promoter.In this study, we focused on using the 20 bp inhibitory element decoy to block negative regulation of the NKX3.1 gene and to up-regulate NKX3.1 expression using synthetic double-stranded oligodeoxynucleotides of the 20 bp inhibitory element. We found in an electrophoretic mobility shift assay experiment that the 20 bp inhibitory decoy presented competitive binding to a specific binding protein of the 20 bp inhibitory element in prostate cancer cell line LNCaP. In luciferase reporter gene assays, we found that the 20 bp inhibitory decoy could enhance NKX3.1 promoter activity, and RT-PCR and Western blot analysis revealed that NKX3.1expression was up-regulated effectively by the transfection with the 20 bp inhibitory decoy. Furthermore,cell proliferation was inhibited by up-regulated NKX3.1 expression induced by the 20 bp inhibitory decoy.

  12. Discriminating the native structure from decoys using scoring functions based on the residue packing in globular proteins.

    Science.gov (United States)

    Bahadur, Ranjit Prasad; Chakrabarti, Pinak

    2009-12-28

    Setting the rules for the identification of a stable conformation of a protein is of utmost importance for the efficient generation of structures in computer simulation. For structure prediction, a considerable number of possible models are generated from which the best model has to be selected. Two scoring functions, Rs and Rp, based on the consideration of packing of residues, which indicate if the conformation of an amino acid sequence is native-like, are presented. These are defined using the solvent accessible surface area (ASA) and the partner number (PN) (other residues that are within 4.5 A) of a particular residue. The two functions evaluate the deviation from the average packing properties (ASA or PN) of all residues in a polypeptide chain corresponding to a model of its three-dimensional structure. While simple in concept and computationally less intensive, both the functions are at least as efficient as any other energy functions in discriminating the native structure from decoys in a large number of standard decoy sets, as well as on models submitted for the targets of CASP7. Rs appears to be slightly more effective than Rp, as determined by the number of times the native structure possesses the minimum value for the function and its separation from the average value for the decoys. Two parameters, Rs and Rp, are discussed that can very efficiently recognize the native fold for a sequence from an ensemble of decoy structures. Unlike many other algorithms that rely on the use of composite scoring function, these are based on a single parameter, viz., the accessible surface area (or the number of residues in contact), but still able to capture the essential attribute of the native fold.

  13. G4-DNA formation in the HRAS promoter and rational design of decoy oligonucleotides for cancer therapy.

    Directory of Open Access Journals (Sweden)

    Alexandro Membrino

    Full Text Available HRAS is a proto-oncogene involved in the tumorigenesis of urinary bladder cancer. In the HRAS promoter we identified two G-rich elements, hras-1 and hras-2, that fold, respectively, into an antiparallel and a parallel quadruplex (qhras-1, qhras-2. When we introduced in sequence hras-1 or hras-2 two point mutations that block quadruplex formation, transcription increased 5-fold, but when we stabilized the G-quadruplexes by guanidinium phthalocyanines, transcription decreased to 20% of control. By ChIP we found that sequence hras-1 is bound only by MAZ, while hras-2 is bound by MAZ and Sp1: two transcription factors recognizing guanine boxes. We also discovered by EMSA that recombinant MAZ-GST binds to both HRAS quadruplexes, while Sp1-GST only binds to qhras-1. The over-expression of MAZ and Sp1 synergistically activates HRAS transcription, while silencing each gene by RNAi results in a strong down-regulation of transcription. All these data indicate that the HRAS G-quadruplexes behave as transcription repressors. Finally, we designed decoy oligonucleotides mimicking the HRAS quadruplexes, bearing (R-1-O-[4-(1-Pyrenylethynyl phenylmethyl] glycerol and LNA modifications to increase their stability and nuclease resistance (G4-decoys. The G4-decoys repressed HRAS transcription and caused a strong antiproliferative effect, mediated by apoptosis, in T24 bladder cancer cells where HRAS is mutated.

  14. Target-Decoy Approach and False Discovery Rate: When Things May Go Wrong

    Science.gov (United States)

    Gupta, Nitin; Bandeira, Nuno; Keich, Uri; Pevzner, Pavel A.

    2011-07-01

    The target-decoy approach (TDA) has done the field of proteomics a great service by filling in the need to estimate the false discovery rates (FDR) of peptide identifications. While TDA is often viewed as a universal solution to the problem of FDR evaluation, we argue that the time has come to critically re-examine TDA and to acknowledge not only its merits but also its demerits. We demonstrate that some popular MS/MS search tools are not TDA-compliant and that it is easy to develop a non-TDA compliant tool that outperforms all TDA-compliant tools. Since the distinction between TDA-compliant and non-TDA compliant tools remains elusive, we are concerned about a possible proliferation of non-TDA-compliant tools in the future (developed with the best intentions). We are also concerned that estimation of the FDR by TDA awkwardly depends on a virtual coin toss and argue that it is important to take the coin toss factor out of our estimation of the FDR. Since computing FDR via TDA suffers from various restrictions, we argue that TDA is not needed when accurate p-values of individual Peptide-Spectrum Matches are available.

  15. The murine gammaherpesvirus-68 gp150 acts as an immunogenic decoy to limit virion neutralization.

    Directory of Open Access Journals (Sweden)

    Laurent Gillet

    Full Text Available Herpesviruses maintain long-term infectivity without marked antigenic variation. They must therefore evade neutralization by other means. Immune sera block murine gammaherpesvirus-68 (MHV-68 infection of fibroblasts, but fail to block and even enhance its infection of IgG Fc receptor-bearing cells, suggesting that the antibody response to infection is actually poor at ablating virion infectivity completely. Here we analyzed this effect further by quantitating the glycoprotein-specific antibody response of MHV-68 carrier mice. Gp150 was much the commonest glycoprotein target and played a predominant role in driving Fc receptor-dependent infection: when gp150-specific antibodies were boosted, Fc receptor-dependent infection increased; and when gp150-specific antibodies were removed, Fc receptor-dependent infection was largely lost. Neither gp150-specific monoclonal antibodies nor gp150-specific polyclonal sera gave significant virion neutralization. Gp150 therefore acts as an immunogenic decoy, distorting the MHV-68-specific antibody response to promote Fc receptor-dependent infection and so compromise virion neutralization. This immune evasion mechanism may be common to many non-essential herpesvirus glycoproteins.

  16. Predictive value of decoy receptor 3 in postoperative nosocomial bacterial meningitis.

    Science.gov (United States)

    Liu, Yong-Juan; Shao, Li-Hua; Wang, Qian; Zhang, Jian; Ma, Rui-Ping; Liu, Hai-Hong; Dong, Xiao-Meng; Ma, Li-Xian

    2014-11-03

    Nosocomial bacterial meningitis requires timely treatment, but what is difficult is the prompt and accurate diagnosis of this disease. The aim of this study was to assess the potential role of decoy receptor 3 (DcR3) levels in the differentiation of bacterial meningitis from non-bacterial meningitis. A total of 123 patients were recruited in this study, among them 80 patients being with bacterial meningitis and 43 patients with non-bacterial meningitis. Bacterial meningitis was confirmed by bacterial culture of cerebrospinal fluid (CSF) culture and enzyme-linked immunosorbent assay (ELISA) was used to detect the level of DcR3 in CSF. CSF levels of DcR3 were statistically significant between patients with bacterial meningitis and those with non-bacterial meningitis (pbacterial meningitis received antibiotic>24 h before CSF sampling, which was much higher than that of non-bacterial meningitis. CSF leucocyte count yielded the highest diagnostic value, with an area under the receiver operating characteristic curve (ROC) of 0.928, followed by DcR3. At a critical value of 0.201 ng/mL for DcR3, the sensitivity and specificity were 78.75% and 81.40% respectively. DcR3 in CSF may be a valuable predictor for differentiating patients with bacterial meningitis from those with non-bacterial meningitis. Further studies are needed for the validation of this study.

  17. Induction of antagonistic soluble decoy receptor tyrosine kinases by intronic polyA activation.

    Science.gov (United States)

    Vorlová, Sandra; Rocco, Gina; Lefave, Clare V; Jodelka, Francine M; Hess, Ken; Hastings, Michelle L; Henke, Erik; Cartegni, Luca

    2011-09-16

    Alternative intronic polyadenylation (IPA) can generate truncated protein isoforms with significantly altered functions. Here, we describe 31 dominant-negative, secreted variant isoforms of receptor tyrosine kinases (RTKs) that are produced by activation of intronic poly(A) sites. We show that blocking U1-snRNP can activate IPA, indicating a larger role for U1-snRNP in RNA surveillance. Moreover, we report the development of an antisense-based method to effectively and specifically activate expression of individual soluble decoy RTKs (sdRTKs) to alter signaling, with potential therapeutic implications. In particular, a quantitative switch from signal transducing full-length vascular endothelial growth factor receptor-2 (VEGFR2/KDR) to a dominant-negative sKDR results in a strong antiangiogenic effect both on directly targeted cells and on naive cells exposed to conditioned media, suggesting a role for this approach in interfering with angiogenic paracrine and autocrine loops. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Early growth response gene-1 decoy oligonucleotides inhibit vascular smooth muscle cell proliferation and neointimal hyperplasia of autogenous vein graft in rabbits.

    Science.gov (United States)

    Wang, Xisheng; Mei, Yunqing; Ji, Qiang; Feng, Jing; Cai, Jianzhi; Xie, Shiliang

    2015-07-01

    The excess proliferation of vascular smooth muscle cells (VSMCs) and the development of intimal hyperplasia is a hallmark of vein graft failure. This study aimed to verify that a single intraoperative transfection of early growth response gene-1 (Egr-1) decoy oligonucleotide (ODN) can suppress vein graft proliferation of VSMCs and intimal hyperplasia. In a rabbit model, jugular veins were treated with Egr-1 decoy ODN, scrambled decoy ODN, Fugene6, or were left untreated, then grafted to the carotid artery. The vein graft samples were obtained 48 h, 1, 2 or 3 weeks after surgery. The thickness of the intima and intima/media ratio in the grafts was analysed by haematoxylin-eosin (HE) staining. The expression of the Egr-1 decoy ODN transfected in the vein was analysed using fluorescent microscopy. Egr-1 mRNA was measured using reverse transcription-polymerase chain reaction. The expression of Egr-1 protein was analysed by Western blot and immunohistochemistry. Transfection efficiency of the ODN was confirmed by 4', 6-diamidino-2-phenylindole staining. In the grafts treated with Egr-1 decoy ODN, our study achieved statistically significant inhibition of intimal hyperplasia by ∼58% at 3 weeks. Transfection of Egr-1 decoy ODNs decreased the protein expression of Egr-1 and Egr-1 mRNA. We confirmed that gene therapy using in vivo transfection of an Egr-1 decoy ODN significantly inhibits proliferation of VSMC and intimal hyperplasia of vein grafts in a rabbit model. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  19. Prospect of Distance Learning

    Science.gov (United States)

    Rahman, Monsurur; Karim, Reza; Byramjee, Framarz

    2015-01-01

    Many educational institutions in the United States are currently offering programs through distance learning, and that trend is rising. In almost all spheres of education a developing country like Bangladesh needs to make available the expertise of the most qualified faculty to her distant people. But the fundamental question remains as to whether…

  20. Human Milk Contains Novel Glycans That Are Potential Decoy Receptors for Neonatal Rotaviruses*

    Science.gov (United States)

    Yu, Ying; Lasanajak, Yi; Song, Xuezheng; Hu, Liya; Ramani, Sasirekha; Mickum, Megan L.; Ashline, David J.; Prasad, B. V. Venkataram; Estes, Mary K.; Reinhold, Vernon N.; Cummings, Richard D.; Smith, David F.

    2014-01-01

    Human milk contains a rich set of soluble, reducing glycans whose functions and bioactivities are not well understood. Because human milk glycans (HMGs) have been implicated as receptors for various pathogens, we explored the functional glycome of human milk using shotgun glycomics. The free glycans from pooled milk samples of donors with mixed Lewis and Secretor phenotypes were labeled with a fluorescent tag and separated via multidimensional HPLC to generate a tagged glycan library containing 247 HMG targets that were printed to generate the HMG shotgun glycan microarray (SGM). To investigate the potential role of HMGs as decoy receptors for rotavirus (RV), a leading cause of severe gastroenteritis in children, we interrogated the HMG SGM with recombinant forms of VP8* domains of the RV outer capsid spike protein VP4 from human neonatal strains N155(G10P[11]) and RV3(G3P[6]) and a bovine strain, B223(G10P[11]). Glycans that were bound by RV attachment proteins were selected for detailed structural analyses using metadata-assisted glycan sequencing, which compiles data on each glycan based on its binding by antibodies and lectins before and after exo- and endo-glycosidase digestion of the SGM, coupled with independent MSn analyses. These complementary structural approaches resulted in the identification of 32 glycans based on RV VP8* binding, many of which are novel HMGs, whose detailed structural assignments by MSn are described in a companion report. Although sialic acid has been thought to be important as a surface receptor for RVs, our studies indicated that sialic acid is not required for binding of glycans to individual VP8* domains. Remarkably, each VP8* recognized specific glycan determinants within a unique subset of related glycan structures where specificity differences arise from subtle differences in glycan structures. PMID:25048705

  1. Expression, Purification, and Biophysical Characterization of a Secreted Anthrax Decoy Fusion Protein in Nicotiana benthamiana

    Science.gov (United States)

    Karuppanan, Kalimuthu; Duhra-Gill, Sifti; Kailemia, Muchena J.; Phu, My L.; Lebrilla, Carlito B.; Dandekar, Abhaya M.; Rodriguez, Raymond L.; Nandi, Somen; McDonald, Karen A.

    2017-01-01

    Anthrax toxin receptor-mediated drug development for blocking anthrax toxin action has received much attention in recent decades. In this study, we produced a secreted anthrax decoy fusion protein comprised of a portion of the human capillary morphogenesis gene-2 (CMG2) protein fused via a linker to the fragment crystallizable (Fc) domain of human immunoglobulin G1 in Nicotiana benthamiana plants using a transient expression system. Using the Cauliflower Mosaic Virus (CaMV) 35S promoter and co-expression with the p19 gene silencing suppressor, we were able to achieve a high level of recombinant CMG2-Fc-Apo (rCMG2-Fc-Apo) protein accumulation. Production kinetics were observed up to eight days post-infiltration, and maximum production of 826 mg/kg fresh leaf weight was observed on day six. Protein A affinity chromatography purification of the rCMG2-Fc-Apo protein from whole leaf extract and apoplast wash fluid showed the homodimeric form under non-reducing gel electrophoresis and mass spectrometry analysis confirmed the molecular integrity of the secreted protein. The N-glycosylation pattern of purified rCMG2-Fc-Apo protein was analysed; the major portion of N-glycans consists of complex type structures in both protein samples. The most abundant (>50%) N-glycan structure was GlcNAc2(Xyl)Man3(Fuc)GlcNAc2 in rCMG2-Fc-Apo recovered from whole leaf extract and apoplast wash fluid. High mannose N-glycan structures were not detected in the apoplast wash fluid preparation, which confirmed the protein secretion. Altogether, these findings demonstrate that high-level production of rCMG2-Fc-Apo can be achieved by transient production in Nicotiana benthamiana plants with apoplast targeting. PMID:28054967

  2. Expression, Purification, and Biophysical Characterization of a Secreted Anthrax Decoy Fusion Protein in Nicotiana benthamiana.

    Science.gov (United States)

    Karuppanan, Kalimuthu; Duhra-Gill, Sifti; Kailemia, Muchena J; Phu, My L; Lebrilla, Carlito B; Dandekar, Abhaya M; Rodriguez, Raymond L; Nandi, Somen; McDonald, Karen A

    2017-01-04

    Anthrax toxin receptor-mediated drug development for blocking anthrax toxin action has received much attention in recent decades. In this study, we produced a secreted anthrax decoy fusion protein comprised of a portion of the human capillary morphogenesis gene-2 (CMG2) protein fused via a linker to the fragment crystallizable (Fc) domain of human immunoglobulin G1 in Nicotiana benthamiana plants using a transient expression system. Using the Cauliflower Mosaic Virus (CaMV) 35S promoter and co-expression with the p19 gene silencing suppressor, we were able to achieve a high level of recombinant CMG2-Fc-Apo (rCMG2-Fc-Apo) protein accumulation. Production kinetics were observed up to eight days post-infiltration, and maximum production of 826 mg/kg fresh leaf weight was observed on day six. Protein A affinity chromatography purification of the rCMG2-Fc-Apo protein from whole leaf extract and apoplast wash fluid showed the homodimeric form under non-reducing gel electrophoresis and mass spectrometry analysis confirmed the molecular integrity of the secreted protein. The N-glycosylation pattern of purified rCMG2-Fc-Apo protein was analysed; the major portion of N-glycans consists of complex type structures in both protein samples. The most abundant (>50%) N-glycan structure was GlcNAc₂(Xyl)Man₃(Fuc)GlcNAc₂ in rCMG2-Fc-Apo recovered from whole leaf extract and apoplast wash fluid. High mannose N-glycan structures were not detected in the apoplast wash fluid preparation, which confirmed the protein secretion. Altogether, these findings demonstrate that high-level production of rCMG2-Fc-Apo can be achieved by transient production in Nicotiana benthamiana plants with apoplast targeting.

  3. Predictive Value of Decoy Receptor 3 in Postoperative Nosocomial Bacterial Meningitis

    Directory of Open Access Journals (Sweden)

    Yong-Juan Liu

    2014-11-01

    Full Text Available Nosocomial bacterial meningitis requires timely treatment, but what is difficult is the prompt and accurate diagnosis of this disease. The aim of this study was to assess the potential role of decoy receptor 3 (DcR3 levels in the differentiation of bacterial meningitis from non-bacterial meningitis. A total of 123 patients were recruited in this study, among them 80 patients being with bacterial meningitis and 43 patients with non-bacterial meningitis. Bacterial meningitis was confirmed by bacterial culture of cerebrospinal fluid (CSF culture and enzyme-linked immunosorbent assay (ELISA was used to detect the level of DcR3 in CSF. CSF levels of DcR3 were statistically significant between patients with bacterial meningitis and those with non-bacterial meningitis (p < 0.001. A total of 48.75% of patients with bacterial meningitis received antibiotic >24 h before CSF sampling, which was much higher than that of non-bacterial meningitis. CSF leucocyte count yielded the highest diagnostic value, with an area under the receiver operating characteristic curve (ROC of 0.928, followed by DcR3. At a critical value of 0.201 ng/mL for DcR3, the sensitivity and specificity were 78.75% and 81.40% respectively. DcR3 in CSF may be a valuable predictor for differentiating patients with bacterial meningitis from those with non-bacterial meningitis. Further studies are needed for the validation of this study.

  4. Empowerment and continuous improvement in the United States, Mexico, Poland, and India: predicting fit on the basis of the dimensions of power distance and individualism.

    Science.gov (United States)

    Robert, C; Probst, T M; Martocchio, J J; Drasgow, F; Lawler, J J

    2000-10-01

    Although variations in national cultures predominate as explanation for the belief that universal approaches to management do not exist, there have been few reports of systematic studies. Data from employees of a single firm with operations in the United States, Mexico, Poland, and India were used to test the fit of empowerment and continuous improvement practices with national culture. Using the theoretical constructs of individualism-collectivism and power distance, the authors predicted that the practices would be more congruent in some cultures than in others and that value congruence would result in job satisfaction. Using structural equations modeling, the authors found that empowerment was negatively associated with satisfaction in India but positively associated in the other 3 samples. Continuous improvement was positively associated with satisfaction in all samples. Substantive, theoretical, and methodological implications are discussed.

  5. Structure-based rational design of a Toll-like receptor 4 (TLR4 decoy receptor with high binding affinity for a target protein.

    Directory of Open Access Journals (Sweden)

    Jieun Han

    Full Text Available Repeat proteins are increasingly attracting much attention as alternative scaffolds to immunoglobulin antibodies due to their unique structural features. Nonetheless, engineering interaction interface and understanding molecular basis for affinity maturation of repeat proteins still remain a challenge. Here, we present a structure-based rational design of a repeat protein with high binding affinity for a target protein. As a model repeat protein, a Toll-like receptor4 (TLR4 decoy receptor composed of leucine-rich repeat (LRR modules was used, and its interaction interface was rationally engineered to increase the binding affinity for myeloid differentiation protein 2 (MD2. Based on the complex crystal structure of the decoy receptor with MD2, we first designed single amino acid substitutions in the decoy receptor, and obtained three variants showing a binding affinity (K(D one-order of magnitude higher than the wild-type decoy receptor. The interacting modes and contributions of individual residues were elucidated by analyzing the crystal structures of the single variants. To further increase the binding affinity, single positive mutations were combined, and two double mutants were shown to have about 3000- and 565-fold higher binding affinities than the wild-type decoy receptor. Molecular dynamics simulations and energetic analysis indicate that an additive effect by two mutations occurring at nearby modules was the major contributor to the remarkable increase in the binding affinities.

  6. Inhibition of cyclic AMP response element-directed transcription by decoy oligonucleotides enhances tumor-specific radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Park, Serk In, E-mail: serkin@korea.edu [Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul (Korea, Republic of); The BK21 Plus Program for Biomedical Sciences, Korea University College of Medicine, Seoul (Korea, Republic of); Department of Medicine and Center for Bone Biology, Vanderbilt University School of Medicine, Nashville, TN (United States); Park, Sung-Jun [Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul (Korea, Republic of); Laboratory of Obesity and Aging Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Lee, Junghan; Kim, Hye Eun; Park, Su Jin; Sohn, Jeong-Won [Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul (Korea, Republic of); Park, Yun Gyu, E-mail: parkyg@korea.ac.kr [Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul (Korea, Republic of)

    2016-01-15

    The radiation stress induces cytotoxic responses of cell death as well as cytoprotective responses of cell survival. Understanding exact cellular mechanism and signal transduction pathways is important in improving cancer radiotherapy. Increasing evidence suggests that cyclic AMP response element binding protein (CREB)/activating transcription factor (ATF) family proteins act as a survival factor and a signaling molecule in response to stress. We postulated that CREB inhibition via CRE decoy oligonucleotide increases tumor cell sensitization to γ-irradiation-induced cytotoxic stress. In the present study, we demonstrate that CREB phosphorylation and CREB DNA-protein complex formation increased in time- and radiation dose-dependent manners, while there was no significant change in total protein level of CREB. In addition, CREB was phosphorylated in response to γ-irradiation through p38 MAPK pathway. Further investigation revealed that CREB blockade by decoy oligonucleotides functionally inhibited transactivation of CREB, and significantly increased radiosensitivity of multiple human cancer cell lines including TP53- and/or RB-mutated cells with minimal effects on normal cells. We also demonstrate that tumor cells ectopically expressing dominant negative mutant CREB (KCREB) and the cells treated with p38 MAPK inhibitors were more sensitive to γ-irradiation than wild type parental cells or control-treated cells. Taken together, we conclude that CREB protects tumor cells from γ-irradiation, and combination of CREB inhibition plus ionizing radiation will be a promising radiotherapeutic approach. - Highlights: • γ-Irradiation induced CREB phosphorylation and CRE-directed transcription in tumor. • γ-Irradiation-induced transcriptional activation of CREB was via p38 MAPK pathway. • CRE blockade increased radiosensitivity of tumor cells but not of normal cells. • CRE decoy oligonucleotides or p38 MAPK inhibitors can be used as radiosensitizers.

  7. Distance Education Use in Rural Schools

    Science.gov (United States)

    Hannum, Wallace H.; Irvin, Matthew J.; Banks, Jonathan B.; Farmer, Thomas W.

    2009-01-01

    A national survey of rural school systems in the United States was conducted to determine the extent to which distance education is being utilized by rural schools, the technologies used, the curriculum areas impacted, the perceived needs for distance education, their satisfaction with distance education, and the barriers to distance education…

  8. Monitoring of West Nile virus, Usutu virus and Meaban virus in waterfowl used as decoys and wild raptors in southern Spain.

    Science.gov (United States)

    Jurado-Tarifa, E; Napp, S; Lecollinet, S; Arenas, A; Beck, C; Cerdà-Cuéllar, M; Fernández-Morente, M; García-Bocanegra, I

    2016-12-01

    In the last decade, the number of emerging flaviviruses described worldwide has increased considerably, with wild birds acting as the main reservoir hosts of these viruses. We carried out an epidemiological survey to determine the seroprevalence of antigenically related flaviviruses, particularly West Nile virus (WNV), Usutu virus (USUV) and Meaban virus (MBV), in waterfowl used as decoys and wild raptors in Andalusia (southern Spain), the region considered to have the highest risk of flaviviruses circulation in Spain. The overall flaviviruses seroprevalence according to bELISA was 13.0% in both in decoys (n=1052) and wild raptors (n=123). Specific antibodies against WNV, USUV and MBV were confirmed by micro virus neutralization tests in 12, 38 and 4 of the seropositive decoys, respectively. This is the first study on WNV and USUV infections in decoys and the first report of MBV infections in waterfowl and raptors. Moreover we report the first description of WNV infections in short-toed snake eagle (Circaetus gallicus) and Montagu's harrier (Circus pygargus). The seropositivity obtained indicates widespread but not homogeneous distribution of WNV and USUV in Andalusia. The results also confirm endemic circulation of WNV, USUV and MBV in both decoys and wild raptors in southern Spain. Our results highlight the need to implement surveillance and control programs not only for WNV but also for other related flaviviruses. Further research is needed to determine the eco-epidemiological role that waterfowl and wild raptors play in the transmission of emerging flaviviruses, especially in decoys, given their close interactions with humans.

  9. Comparison and analysis on test methods of infrared radiant intensity of infrared decoy

    Science.gov (United States)

    Chen, Chunsheng; Dai, Mengyan; Liu, Haifeng; Fang, Guofeng; Xie, Changyou; Zhang, Tong

    2014-11-01

    The research on infrared radiant characteristics of typical target is important for the detection and recognition of target, infrared simulation calculation and design of electro-optical countermeasures. Thus it is essential to select appropriate test method and optimal calculation method to improve the test accuracy and reliability of infrared radiant intensity. In this paper, three instruments including SR5000 spectroradiometer (CI, MigdalHaEmek, Israel), remote sensing interferometer spectrometer Tensor37 (Bruker, Germany) and Image IR8325 (InfraTec Ltd, Germany) mid-infrared thermal imager were applied to test the infrared radiant (1μm-3μm - 3μm-5μm) intensity of decoy samples. Three methods were designed based on two operational principles including direct test and indirect test. The SR5000 spectroradiometer which is able to obtain the value of radian intensity immediately is regard as direct test. The other two instruments which deduce and calculate infrared radiant intensity according to Planck's law and Lambert's cosine law with some preliminary tested parameters such as the response voltage - the distribution of infrared radiant temperature of flaming samples and calibrated data by blackbody, however, are regard as indirect test. Reasons for the diversity of experiment results were provided through analysis on the concrete measurement theory and detailed calculation methods. Moreover, some rules and suggestions were put forward to improve the test accuracy and reliability of infrared radiant intensity when different methods were adopted. It is shown from experiment results that the average mid-infrared radiant intensity obtained from SR5000 was about 903W/Sr in near-infrared band - whereas Tensor 37 and Image IR8325 was about 834W/Sr and 547 W/Sr respectively. It was proved that maximum relative of calculated results from remote sensing interferometer spectrometer Tensor37 and results measured with SR5000 spectroradiometer is below 13%, which meet the

  10. TRAM-Derived Decoy Peptides inhibits the inflammatory response in mouse mammary epithelial cells and a mastitis model in mice.

    Science.gov (United States)

    Hu, Xiaoyu; Tian, Yuan; Wang, Tiancheng; Zhang, Wenlong; Wang, Wei; Gao, Xuejiao; Qu, Shihui; Cao, Yongguo; Zhang, Naisheng

    2015-10-05

    It has been proved that TRAM-Derived Decoy peptides have anti-inflammatory properties. In this study, we synthesized a TRAM-Derived decoy peptide (TM6), belongs to TRAM TIR domain, of which sequence is "N"-RQIKIWFQNRRMKWK, KENFLRDTWCNFQFY-"C" and evaluated the effects of TM6 on lipopolysaccharide-induced mastitis in mice. In vivo, LPS-induced mice mastitis model was established by injection of LPS through the duct of mammary gland. TM6 was injected 1h before or after LPS treatment. In vitro, primary mouse mammary epithelial cells were used to investigate the effects of TM6 on LPS-induced inflammatory responses. The results showed that TM6 inhibited LPS-induced mammary gland histopathologic changes, MPO activity, and TNF-α, IL-1β and IL-6 production in mice. In vitro, TM6 significantly inhibited LPS-induced TNF-α and IL-6 production, as well as NF-κB and MAPKs activation. In conclusion, this study demonstrated that TM6 had protective effects on LPS-mastitis and may be a promising therapeutic reagent for mastitis treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. An overview on distance and pseudo distance functions and their applications

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiangyang; DING Han; ZHONG Binglin; XIONG Youlun

    2003-01-01

    The fast and accurate collision detection and distance calculation between geometric models is fundamental in robotics, manufacturing and computer-simulated environments. This paper surveys the state of the art in the theory and algorithms of distance and pseudo distance functions between convex sets. An overview on the existing results, including fast algorithms for distance calculation, definitions and properties of various pseudo distance functions (the J-function, the growth distance, and the pseudo minimum translational distance), is presented. The distance and pseudo distance functions are versatile in a wide range of areas. Their applications in robot motion planning, grasp analysis/synthesis, form error evaluation, and engineering optimization is demonstrated.

  12. Doctoral education from a distance.

    Science.gov (United States)

    Effken, Judith A

    2008-12-01

    This article describes the environmental factors that have contributed to the recent rapid growth of nursing doctoral education at a distance. Early and recent efforts to deliver distance doctoral education are discussed, using The University of Arizona College of Nursing experience as the key exemplar. The Community of Inquiry model is introduced as an appropriate model for doctoral education and then used as a framework to evaluate the current state of the art in distance doctoral nursing education. Successes and challenges in delivering doctoral education from a distance are described.

  13. Distance, Borders, and Time

    DEFF Research Database (Denmark)

    Skillicorn, David; Walther, Olivier; Zheng, Quan

    is a combination of the physical geography of the target environment, and the mental and physical cost of following a seemingly random pattern of attacks. Focusing on the distance and time between attacks and taking into consideration the transaction costs that state boundaries impose, we wish to understand what......” of North and West Africa that depicts the permeability to violence. A better understanding of how location, time, and borders condition attacks enables planning, prepositioning, and response....

  14. The Regulation of Technology-Assisted Distance Counseling and Supervision in the United States: An Analysis of Current Extent, Trends, and Implications

    Science.gov (United States)

    McAdams, Charles R.; Wyatt, Kristi Lee

    2010-01-01

    Counseling licensure boards report emerging needs to regulate technology-assisted distance counseling and supervision. An analysis of published regulations and telephone interviews with board administrators nationwide suggests that boards agree generally on 7 aspects of technology-assisted distance practice that need to be regulated. Nevertheless,…

  15. Assessment of topographic and drainage network controls on debris-flow travel distance along the west coast of the United States

    Science.gov (United States)

    Coe, Jeffrey A.; Reid, Mark E.; Brien, Dainne L.; Michael, John A.

    2011-01-01

    To better understand controls on debris-flow entrainment and travel distance, we examined topographic and drainage network characteristics of initiation locations in two separate debris-flow prone areas located 700 km apart along the west coast of the U.S. One area was located in northern California, the other in southern Oregon. In both areas, debris flows mobilized from slides during large storms, but, when stratified by number of contributing initiation locations, median debris-flow travel distances in Oregon were 5 to 8 times longer than median distances in California. Debris flows in Oregon readily entrained channel material; entrainment in California was minimal. To elucidate this difference, we registered initiation locations to high-resolution airborne LiDAR, and then examined travel distances with respect to values of slope, upslope contributing area, planform curvature, distance from initiation locations to the drainage network, and number of initiation areas that contributed to flows. Results show distinct differences in the topographic and drainage network characteristics of debris-flow initiation locations between the two study areas. Slope and planform curvature of initiation locations (landslide headscarps), commonly used to predict landslide-prone areas, were not useful for predicting debris-flow travel distances. However, a positive, power-law relation exists between median debris-flow travel distance and the number of contributing debris-flow initiation locations. Moreover, contributing area and the proximity of the initiation locations to the drainage network both influenced travel distances, but proximity to the drainage network was the better predictor of travel distance. In both study areas, flows that interacted with the drainage network flowed significantly farther than those that did not. In California, initiation sites within 60 m of the network were likely to reach the network and generate longtraveled flows; in Oregon, the threshold was

  16. Potential use of fucose-appended dendrimer/α-cyclodextrin conjugates as NF-κB decoy carriers for the treatment of lipopolysaccharide-induced fulminant hepatitis in mice.

    Science.gov (United States)

    Akao, Chiho; Tanaka, Takahiro; Onodera, Risako; Ohyama, Ayumu; Sato, Nana; Motoyama, Keiichi; Higashi, Taishi; Arima, Hidetoshi

    2014-11-10

    The purpose of the present study is to treat lipopolysaccharide (LPS)-induced fulminant hepatitis by NF-κB decoy complex with fucose-appended dendrimer (generation 2; G2) conjugate with α-cyclodextrin (Fuc-S-α-CDE (G2)). Fuc-S-α-CDE (G2, average degree of substitution of fucose (DSF2))/NF-κB decoy complex significantly suppressed nitric oxide and tumor necrosis factor-α (TNF-α) production from LPS-stimulated NR8383 cells, a rat alveolar macrophage cell line, by adequate physicochemical properties and fucose receptor-mediated cellular uptake. Intravenous injection of Fuc-S-α-CDE (G2, DSF2)/NF-κB decoy complex extended the survival of LPS-induced fulminant hepatitis model mice. In addition, Fuc-S-α-CDE (G2, DSF2)/NF-κB decoy complex administered intravenously highly accumulated in the liver, compared to naked NF-κB decoy alone. Furthermore, the liver accumulation of Fuc-S-α-CDE (G2, DSF2)/NF-κB decoy complex was inhibited by the pretreatment with GdCl3, a specific inhibitor of Kupffer cell uptake. Also, the serum aspartate aminotransferase, alanine aminotransferase and TNF-α levels in LPS-induced fulminant hepatitis model mice were significantly attenuated by the treatment with Fuc-S-α-CDE (G2, DSF2)/NF-κB decoy complex, compared with naked NF-κB decoy alone. Taken together, these results suggest that Fuc-S-α-CDE (G2, DSF2) has the potential for a novel Kupffer cell-selective NF-κB decoy carrier for the treatment of LPS-induced fulminant hepatitis in mice.

  17. The Distance Field Model and Distance Constrained MAP Adaptation Algorithm

    Institute of Scientific and Technical Information of China (English)

    YUPeng; WANGZuoying

    2003-01-01

    Spatial structure information, i.e., the rel-ative position information of phonetic states in the feature space, is long to be carefully researched yet. In this pa-per, a new model named “Distance Field” is proposed to describe the spatial structure information. Based on this model, a modified MAP adaptation algorithm named dis-tance constrained maximum a poateriori (DCMAP) is in-troduced. The distance field model gives large penalty when the spatial structure is destroyed. As a result the DCMAP reserves the spatial structure information in adaptation process. Experiments show the Distance Field Model improves the performance of MAP adapta-tion. Further results show DCMAP has strong cross-state estimation ability, which is used to train a well-performed speaker-dependent model by data from only part of pho-

  18. Distance spectra and Distance energy of Integral Circulant Graphs

    CERN Document Server

    c, Aleksandar Ili\\'

    2011-01-01

    The distance energy of a graph $G$ is a recently developed energy-type invariant, defined as the sum of absolute values of the eigenvalues of the distance matrix of $G$. There was a vast research for the pairs and families of non-cospectral graphs having equal distance energy, and most of these constructions were based on the join of graphs. A graph is called circulant if it is Cayley graph on the circulant group, i.e. its adjacency matrix is circulant. A graph is called integral if all eigenvalues of its adjacency matrix are integers. Integral circulant graphs play an important role in modeling quantum spin networks supporting the perfect state transfer. In this paper, we characterize the distance spectra of integral circulant graphs and prove that these graphs have integral eigenvalues of distance matrix $D$. Furthermore, we calculate the distance spectra and distance energy of unitary Cayley graphs. In conclusion, we present two families of pairs $(G_1, G_2)$ of integral circulant graphs with equal distanc...

  19. Distance education: turf and technology.

    Science.gov (United States)

    Pickard, M R

    1992-07-01

    Distance learning fits with the mission and strategic plan of the University of Texas at Arlington. We believe these educational opportunities in nursing are highly desirable. The Board of Nurse Examiners for the State of Texas has approved this project and the Texas Higher Education Coordinating Board has approved it as a pilot project. The school will continue evaluation and creative problem-solving in the use of distance education.

  20. Perspectives of Research on Distance Education.

    Science.gov (United States)

    Holmberg, Borje

    The history of research on distance education was studied. Major research done on distance education in such diverse areas as the United States, Venezuela, and Europe was analyzed. It was discovered that the earliest attempts to develop theories of distance education were mainly concerned with identifying its very concept. Like most educational…

  1. Deterministic Secure Quantum Communication with Cluster State and Bell-Basis Measurements

    Institute of Scientific and Technical Information of China (English)

    YUAN Hao; HE Qin; HU Xiao-Yuan; HOU Kui; HAN Lian-Fang; SHI Shou-Hua

    2008-01-01

    We present a novel protocol for deterministic secure quantum communication by using the four-qubit cluster state as quantum channel. It is shown that two legitimate users can directly transmit the secret messages based on Bell-basis measurements and classical communication. The present protocol makes use of the ideas of block transmission and decoy particle checking technique. It has a high capacity as each cluster state can carry two bits of information, and has a high intrinsic efficiency because almost all the instances except the decoy checking particles (its number is negligible) are useful. Furthermore, this protocol is feasible with present-day technique.

  2. Encyclopedia of distances

    CERN Document Server

    Deza, Michel Marie

    2016-01-01

    This 4th edition of the leading reference volume on distance metrics is characterized by updated and rewritten sections on some items suggested by experts and readers, as well a general streamlining of content and the addition of essential new topics. Though the structure remains unchanged, the new edition also explores recent advances in the use of distances and metrics for e.g. generalized distances, probability theory, graph theory, coding theory, data analysis. New topics in the purely mathematical sections include e.g. the Vitanyi multiset-metric, algebraic point-conic distance, triangular ratio metric, Rossi-Hamming metric, Taneja distance, spectral semimetric between graphs, channel metrization, and Maryland bridge distance. The multidisciplinary sections have also been supplemented with new topics, including: dynamic time wrapping distance, memory distance, allometry, atmospheric depth, elliptic orbit distance, VLBI distance measurements, the astronomical system of units, and walkability distance. Lea...

  3. I can do perfectly well without a car! An exploration of stated preferences for middle-distance travel using Q-methodology

    NARCIS (Netherlands)

    Exel, N.J.A.; Graaf, de G.; Rietveld, P.

    2011-01-01

    This article presents the results of a study exploring travellers' preferences for middle-distance travel using Q-methodology. Respondents rank-ordered 42 opinion statements regarding travel choice and motivations for travel in general and for car and public transport as alternative travel modes.

  4. MAZ-binding G4-decoy with locked nucleic acid and twisted intercalating nucleic acid modifications suppresses KRAS in pancreatic cancer cells and delays tumor growth in mice

    DEFF Research Database (Denmark)

    Cogoi, Susanna; Zorzet, Sonia; Rapozzi, Valentina;

    2013-01-01

    KRAS mutations are primary genetic lesions leading to pancreatic cancer. The promoter of human KRAS contains a nuclease-hypersensitive element (NHE) that can fold in G4-DNA structures binding to nuclear proteins, including MAZ (myc-associated zinc-finger). Here, we report that MAZ activates KRAS...... transcription. To knockdown oncogenic KRAS in pancreatic cancer cells, we designed oligonucleotides that mimic one of the G-quadruplexes formed by NHE (G4-decoys). To increase their nuclease resistance, two locked nucleic acid (LNA) modifications were introduced at the 3'-end, whereas to enhance the folding...... the Kaplan-Meier median survival time by 70%. Together, our data show that MAZ-specific G4-decoys mimicking a KRAS quadruplex are promising for pancreatic cancer therapy....

  5. Distance Education Council.

    Science.gov (United States)

    Indira Gandhi National Open University, New Delhi (India). Distance Education Council.

    Since its inception in India in 1962, distance education has grown in popularity. The Distance Education Council (DEC) directs distance learning within India's higher education system. The DEC's promotion, coordination, and maintenance of standards for distance education are its three major roles. Its initiatives include grants, support for…

  6. Training for Distance Teaching through Distance Learning.

    Science.gov (United States)

    Cadorath, Jill; Harris, Simon; Encinas, Fatima

    2002-01-01

    Describes a mixed-mode bachelor degree course in English language teaching at the Universidad Autonoma de Puebla (Mexico) that was designed to help practicing teachers write appropriate distance education materials by giving them the experience of being distance students. Includes a course outline and results of a course evaluation. (Author/LRW)

  7. Iterative Knowledge-Based Scoring Functions Derived from Rigid and Flexible Decoy Structures: Evaluation with the 2013 and 2014 CSAR Benchmarks.

    Science.gov (United States)

    Yan, Chengfei; Grinter, Sam Z; Merideth, Benjamin Ryan; Ma, Zhiwei; Zou, Xiaoqin

    2016-06-27

    In this study, we developed two iterative knowledge-based scoring functions, ITScore_pdbbind(rigid) and ITScore_pdbbind(flex), using rigid decoy structures and flexible decoy structures, respectively, that were generated from the protein-ligand complexes in the refined set of PDBbind 2012. These two scoring functions were evaluated using the 2013 and 2014 CSAR benchmarks. The results were compared with the results of two other scoring functions, the Vina scoring function and ITScore, the scoring function that we previously developed from rigid decoy structures for a smaller set of protein-ligand complexes. A graph-based method was developed to evaluate the root-mean-square deviation between two conformations of the same ligand with different atom names and orders due to different file preparations, and the program is freely available. Our study showed that the two new scoring functions developed from the larger training set yielded significantly improved performance in binding mode predictions. For binding affinity predictions, all four scoring functions showed protein-dependent performance. We suggest the development of protein-family-dependent scoring functions for accurate binding affinity prediction.

  8. Structure determination of uniformly {sup 13}C, {sup 15}N labeled protein using qualitative distance restraints from MAS solid-state {sup 13}C-NMR observed paramagnetic relaxation enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Tamaki, Hajime [Hokkaido University, Graduate School of Life Science (Japan); Egawa, Ayako [Osaka University, Institute for Protein Research (Japan); Kido, Kouki [Hokkaido University, Graduate School of Life Science (Japan); Kameda, Tomoshi [National Institute of Advanced Industrial Science and Technology, Biotechnology Research Institute for Drug Discovery (Japan); Kamiya, Masakatsu; Kikukawa, Takashi; Aizawa, Tomoyasu [Hokkaido University, Faculty of Advanced Life Science (Japan); Fujiwara, Toshimichi [Osaka University, Institute for Protein Research (Japan); Demura, Makoto, E-mail: demura@sci.hokudai.ac.jp [Hokkaido University, Faculty of Advanced Life Science (Japan)

    2016-01-15

    Magic angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) is a powerful method for structure determination of insoluble biomolecules. However, structure determination by MAS solid-state NMR remains challenging because it is difficult to obtain a sufficient amount of distance restraints owing to spectral complexity. Collection of distance restraints from paramagnetic relaxation enhancement (PRE) is a promising approach to alleviate this barrier. However, the precision of distance restraints provided by PRE is limited in solid-state NMR because of incomplete averaged interactions and intermolecular PREs. In this report, the backbone structure of the B1 domain of streptococcal protein G (GB1) has been successfully determined by combining the CS-Rosetta protocol and qualitative PRE restraints. The derived structure has a Cα RMSD of 1.49 Å relative to the X-ray structure. It is noteworthy that our protocol can determine the correct structure from only three cysteine-EDTA-Mn{sup 2+} mutants because this number of PRE sites is insufficient when using a conventional structure calculation method based on restrained molecular dynamics and simulated annealing. This study shows that qualitative PRE restraints can be employed effectively for protein structure determination from a limited conformational sampling space using a protein fragment library.

  9. Provision of educational service with the use of distance technologies for disabled persons (case study: the state of Alaska and Nothern regions of the Russian Federation

    Directory of Open Access Journals (Sweden)

    V. A. Lipatov

    2016-01-01

    Full Text Available The distance education contributes to the solution of educational problems of disabled persons. The study of foreign experience is extremely important. North American universities saved up a wide experience in this sphere. Unlike self-made software products created by many Russian universities, Blackboard is the leading educational software package that professionally helps to solve educational problems of disabled persons. The international University of the Arctic has a growing interest in the use of information communication technologies and open educational resources and networks. In 2008 the subject network of University of the Arctic on distance education and e-learning began to function. The Internet and distance learning creates a new opportunity for disabled persons. Main goal: Whether distance education on Alaska and in Northern and Siberian regions of the Russian Federation promotes the solution of educational problems of the North for disabled persons. Main research problems: to reveal modern educational Arctic problems for disabled persons; to analyse specifics of remote education; to analyse a question of distance training of the circumpolar North; to carry out the comparative analysis of distance training on Alaska and in Russian northern and the Siberian regions; to analyse a contribution of distance training to wider problems of the Arctic policy and management. Relevance of work: The Arctic Human Development Report I specifi es that there are very few circumpolar researches in the fi eld of education, including for disabled persons. This article can begin initial discussion of a subject which can be in addition studied in future works. An emerging trend for Arctic education is its increasing accessibility. Accessibility is about students being able to take classes and fulfi ll their potential, that is, it concerns their possibilities for attending school, both physically and culturally. Even though this

  10. Provision of educational service with the use of distance technologies for disabled persons (case study: the state of Alaska and Nothern regions of the Russian Federation)

    OpenAIRE

    V. A. Lipatov

    2016-01-01

    The distance education contributes to the solution of educational problems of disabled persons. The study of foreign experience is extremely important. North American universities saved up a wide experience in this sphere. Unlike self-made software products created by many Russian universities, Blackboard is the leading educational software package that professionally helps to solve educational problems of disabled persons. The international University of the Arctic has a growing interest in ...

  11. Encyclopedia of distances

    CERN Document Server

    Deza, Michel Marie

    2014-01-01

    This updated and revised third edition of the leading reference volume on distance metrics includes new items from very active research areas in the use of distances and metrics such as geometry, graph theory, probability theory and analysis. Among the new topics included are, for example, polyhedral metric space, nearness matrix problems, distances between belief assignments, distance-related animal settings, diamond-cutting distances, natural units of length, Heidegger’s de-severance distance, and brain distances. The publication of this volume coincides with intensifying research efforts into metric spaces and especially distance design for applications. Accurate metrics have become a crucial goal in computational biology, image analysis, speech recognition and information retrieval. Leaving aside the practical questions that arise during the selection of a ‘good’ distance function, this work focuses on providing the research community with an invaluable comprehensive listing of the main available di...

  12. Reducing the distance in distance-caregiving by technology innovation

    Directory of Open Access Journals (Sweden)

    Lazelle E Benefield

    2007-07-01

    Full Text Available Lazelle E Benefield1, Cornelia Beck21College of Nursing, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA; 2Pat & Willard Walker Family Memory Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USAAbstract: Family caregivers are responsible for the home care of over 34 million older adults in the United States. For many, the elder family member lives more than an hour’s distance away. Distance caregiving is a growing alternative to more familiar models where: 1 the elder and the family caregiver(s may reside in the same household; or 2 the family caregiver may live nearby but not in the same household as the elder. The distance caregiving model involves elders and their family caregivers who live at some distance, defined as more than a 60-minute commute, from one another. Evidence suggests that distance caregiving is a distinct phenomenon, differs substantially from on-site family caregiving, and requires additional assistance to support the physical, social, and contextual dimensions of the caregiving process. Technology-based assists could virtually connect the caregiver and elder and provide strong support that addresses the elder’s physical, social, cognitive, and/or sensory impairments. Therefore, in today’s era of high technology, it is surprising that so few affordable innovations are being marketed for distance caregiving. This article addresses distance caregiving, proposes the use of technology innovation to support caregiving, and suggests a research agenda to better inform policy decisions related to the unique needs of this situation.Keywords: caregiving, family, distance, technology, elders

  13. Novel VEGF decoy receptor fusion protein conbercept targeting multiple VEGF isoforms provide remarkable anti-angiogenesis effect in vivo.

    Directory of Open Access Journals (Sweden)

    Qin Wang

    Full Text Available VEGF family factors are known to be the principal stimulators of abnormal angiogenesis, which play a fundamental role in tumor and various ocular diseases. Inhibition of VEGF is widely applied in antiangiogenic therapy. Conbercept is a novel decoy receptor protein constructed by fusing VEGF receptor 1 and VEGF receptor 2 extracellular domains with the Fc region of human immunoglobulin. In this study, we systematically evaluated the binding affinity of conbercept with VEGF isoforms and PlGF by using anti-VEGF antibody (Avastin as reference. BIACORE and ELISA assay results indicated that conbercept could bind different VEGF-A isoforms with higher affinity than reference. Furthermore, conbercept could also bind VEGF-B and PlGF, whereas Avastin showed no binding. Oxygen-induced retinopathy model showed that conbercept could inhibit the formation of neovasularizations. In tumor-bearing nude mice, conbercept could also suppress tumor growth very effectively in vivo. Overall, our study have demonstrated that conbercept could bind with high affinity to multiple VEGF isoforms and consequently provide remarkable anti-angiogenic effect, suggesting the possibility to treat angiogenesis-related diseases such as cancer and wet AMD etc.

  14. Decoy receptor 3 suppresses B cell functions and has a negative correlation with disease activity in rheumatoid arthritis.

    Science.gov (United States)

    Chen, Ming-Han; Liu, Po-Chun; Chang, Chien-Wen; Chen, Yi-Ann; Chen, Ming-Huang; Liu, Chun-Yu; Leu, Chuen-Miin; Lin, Hsiao-Yi

    2014-01-01

    The decoy receptor 3 (DcR3) is a member of the tumour necrosis factor (TNF) receptor superfamily and may regulate inflammation. The aim of this study was to investigate the role of DcR3 in B cell functions and its correlation to disease activity in patients with rheumatoid arthritis (RA). The concentrations of DcR3 and TNF-α were measured by ELISA. B cell proliferation was assessed by quantification of 3H-thymidine uptake. Staphylococcus aureus Cowan (SAC) strain were used to stimulate B cell proliferation and TNF-α production. Compared to the osteoarthritis (OA) patients, the RA group had higher synovial DcR3 levels (3273.6±1623.2 vs. 1594.8±1190.0 pg/ml, p=0.003), which were negatively correlated with the serum erythrocyte sedimentation rate and Disease Activity Score using 28 joint counts (DAS28) scores (r=-0.560, p=0.002; r=-0.579, pnegative correlation between DcR3 level and disease activity in RA patients. Our findings imply that DcR3 may be used as a biomarker for disease activity and a potential therapeutic agent in the treatment of RA.

  15. Continuity Properties of Distances for Markov Processes

    DEFF Research Database (Denmark)

    Jaeger, Manfred; Mao, Hua; Larsen, Kim Guldstrand

    2014-01-01

    In this paper we investigate distance functions on finite state Markov processes that measure the behavioural similarity of non-bisimilar processes. We consider both probabilistic bisimilarity metrics, and trace-based distances derived from standard Lp and Kullback-Leibler distances. Two desirable...... continuity properties for such distances are identified. We then establish a number of results that show that these two properties are in conflict, and not simultaneously fulfilled by any of our candidate natural distance functions. An impossibility result is derived that explains to some extent...

  16. Distance Education Instructional Model Applications.

    Science.gov (United States)

    Jackman, Diane H.; Swan, Michael K.

    1995-01-01

    A survey of graduate students involved in distance education on North Dakota State University's Interactive Video Network included 80 on campus and 13 off. The instructional models rated most effective were role playing, simulation, jurisprudential (Socratic method), memorization, synectics, and inquiry. Direct instruction was rated least…

  17. Distances from Planetary Nebulae

    CERN Document Server

    Ciardullo, R

    2003-01-01

    The [O III] 5007 planetary nebula luminosity function (PNLF) occupies an important place on the extragalactic distance ladder. Since it is the only method that is applicable to all the large galaxies of the Local Supercluster, it is uniquely useful for cross-checking results and linking the Population I and Population II distance scales. We review the physics underlying the method, demonstrate its precision, and illustrate its value by comparing its distances to distances obtained from Cepheids and the Surface Brightness Fluctuation (SBF) method. We use the Cepheid and PNLF distances to 13 galaxies to show that the metallicity dependence of the PNLF cutoff is in excellent agreement with that predicted from theory, and that no additional systematic corrections are needed for either method. However, when we compare the Cepheid-calibrated PNLF distance scale with the Cepheid-calibrated SBF distance scale, we find a significant offset: although the relative distances of both methods are in excellent agreement, th...

  18. A generalized evidence distance

    Institute of Scientific and Technical Information of China (English)

    Hongming Mo; Xi Lu; Yong Deng

    2016-01-01

    How to efficiently measure the distance between two basic probability assignments (BPAs) is an open issue. In this paper, a new method to measure the distance between two BPAs is proposed, based on two existing measures of evidence distance. The new proposed method is comprehen-sive and generalized. Numerical examples are used to ilus-trate the effectiveness of the proposed method.

  19. Center—Distance Continuous Probability Models and the Distance Measure

    Institute of Scientific and Technical Information of China (English)

    郑方; 吴文虎; 等

    1998-01-01

    In this paper,a new statistic model named Center-Distance Continuous Probability Model(CDCPM)for speech recognition is described,which is based on Center-Distance Normal(CDN)distribution.In a CDCPM,the probability transition matrix is omitted,and the observation probability density function(PDF)in each state is in the form of embedded multiple-model(EMM)based on the Nearest Neighbour rule.The experimental results on two giant real-world Chinese speech databases and a real-world continuous-manner 2000 phrase system show that this model is a powerful one.Also,a distance measure for CDPMs is proposed which is based on the Bayesian minimum classification error(MCE) discrimination.

  20. Tourists consuming distance

    DEFF Research Database (Denmark)

    Larsen, Gunvor Riber

    The environmental impact of tourism mobility is linked to the distances travelled in order to reach a holiday destination, and with tourists travelling more and further than previously, an understanding of how the tourists view the distance they travel across becomes relevant. Based on interviews...... contribute to an understanding of how it is possible to change tourism travel behaviour towards becoming more sustainable. How tourists 'consume distance' is discussed, from the practical level of actually driving the car or sitting in the air plane, to the symbolic consumption of distance that occurs when...... travelling on holiday becomes part of a lifestyle and a social positioning game. Further, different types of tourist distance consumers are identified, ranging from the reluctant to the deliberate and nonchalant distance consumers, who display very differing attitudes towards the distance they all travel...

  1. Learning string edit distance

    CERN Document Server

    Ristad, E S; Ristad, Eric Sven; Yianilos, Peter N.

    1996-01-01

    In many applications, it is necessary to determine the similarity of two strings. A widely-used notion of string similarity is the edit distance: the minimum number of insertions, deletions, and substitutions required to transform one string into the other. In this report, we provide a stochastic model for string edit distance. Our stochastic model allows us to learn a string edit distance function from a corpus of examples. We illustrate the utility of our approach by applying it to the difficult problem of learning the pronunciation of words in conversational speech. In this application, we learn a string edit distance with one fourth the error rate of the untrained Levenshtein distance. Our approach is applicable to any string classification problem that may be solved using a similarity function against a database of labeled prototypes. Keywords: string edit distance, Levenshtein distance, stochastic transduction, syntactic pattern recognition, prototype dictionary, spelling correction, string correction, ...

  2. Interface Simulation Distances

    Directory of Open Access Journals (Sweden)

    Pavol Černý

    2012-10-01

    Full Text Available The classical (boolean notion of refinement for behavioral interfaces of system components is the alternating refinement preorder. In this paper, we define a distance for interfaces, called interface simulation distance. It makes the alternating refinement preorder quantitative by, intuitively, tolerating errors (while counting them in the alternating simulation game. We show that the interface simulation distance satisfies the triangle inequality, that the distance between two interfaces does not increase under parallel composition with a third interface, and that the distance between two interfaces can be bounded from above and below by distances between abstractions of the two interfaces. We illustrate the framework, and the properties of the distances under composition of interfaces, with two case studies.

  3. Distance Education in Technological Age

    Directory of Open Access Journals (Sweden)

    R .C. SHARMA

    2005-04-01

    Full Text Available Distance Education in Technological AgeRomesh Verma (Editor, New Delhi: Anmol Publications, 2005, ISBN 81-261-2210-2, pp. 419 Reviewed by R C SHARMARegional DirectorIndira Gandhi National Open University-INDIA The advancements in information and communication technologies have brought significant changes in the way the open and distance learning are provided to the learners. The impact of such changes is quite visible in both developed and developing countries. Switching over to online mode, joining hands with private initiatives and making a presence in foreign waters, are some of the hallmarks of the open and distance education (ODE institutions in developing countries. The compilation of twenty six essays on themes as applicable to ODE has resulted in the book, “Distance Education in Technological Age”. These essays follow a progressive style of narration, starting from describing conceptual framework of distance education, how the distance education was emerged on the global scene and in India, and then goes on to discuss emergence of online distance education and research aspects in ODE. The initial four chapters provide a detailed account of historical development and growth of distance education in India and State Open University and National Open University Model in India . Student support services are pivot to any distance education and much of its success depends on how well the support services are provided. These are discussed from national and international perspective. The issues of collaborative learning, learning on demand, life long learning, learning-unlearning and re-learning model and strategic alliances have also given due space by the authors. An assortment of technologies like communication technology, domestic technology, information technology, mass media and entertainment technology, media technology and educational technology give an idea of how these technologies are being adopted in the open universities. The study

  4. Elevated Serum Levels of the Antiapoptotic Protein Decoy-Receptor 3 Are Associated with Advanced Liver Disease

    Directory of Open Access Journals (Sweden)

    Giorgos Bamias

    2016-01-01

    Full Text Available Background. Decoy-receptor 3 (DcR3 exerts antiapoptotic and immunomodulatory function and is overexpressed in neoplastic and inflammatory conditions. Serum DcR3 (sDcR3 levels during the chronic hepatitis/cirrhosis/hepatocellular carcinoma (HCC sequence have not been explored. Objective. To assess the levels and significance of sDcR3 protein in various stages of chronic liver disease. Methods. We compared sDcR3 levels between healthy controls and patients with chronic viral hepatitis (CVH, decompensated cirrhosis (DC, and HCC. Correlations between sDcR3 levels and various patient- and disease-related factors were analyzed. Results. sDcR3 levels were significantly higher in patients with CVH than in controls (P<0.01. sDcR3 levels were elevated in DC and HCC, being significantly higher compared not only to controls (P<0.001 for both but to CVH patients as well (P<0.001 for both. In addition, DcR3 protein was detected in large quantities in the ascitic fluid of cirrhotics. In patients with CVH, sDcR3 significantly correlated to fibrosis severity, as estimated by Ishak score (P=0.019 or by liver stiffness measured with elastography (Spearman r=0.698, P<0.001. In cirrhotic patients, significant positive correlations were observed between sDcR3 levels and markers of severity of hepatic impairment, including MELD score (r=0.653, P<0.001. Conclusions. Circulating levels of DcR3 are elevated during chronic liver disease and correlate with severity of liver damage. sDcR3 may serve as marker for liver fibrosis severity and progression to end-stage liver disease.

  5. Enhanced expression of the decoy receptor IL-13Rα2 in macrophages of Schistosoma japonicum-infected mice

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; SHEN Yu-xian; LI Jing; ZHANG Shi-hai; LUO Qing-li; ZHONG Zhen-rong; JIANG Zuo-jun; SHEN Ji-long

    2009-01-01

    Background Type 2 cytokine interleukin (IL)-13 and its decoy receptor, IL-13 receptor (R)α2 appear to play a major role in tissue fibrosis of schistosomiasis and asthma. IL-13 is a key regulator of the extracellular matrix (ECM). It is known to signal to cells by binding to the IL-13Ra1, which then heterodimerizes with IL-4Rα. In contrast, IL-13Rα2 binds IL-13 with high affinity but does not signal. IL-13Rα2 is known to down-regulate granulomatous inflammation and prolong host survival in Schistosoma mansoni (S. Mansoni) infection, but little is known about the location and expression level of IL-13Ra2 in the context of S. Japonicum infection. Methods We established S. Japonicum-infected mouse models. Kinetic serum levels of IL-13Rα2 were examined with ELISA. IL-13Rα2 mRNA and protein of liver tissues were determined by PCR and immunoblotting analysis, respectively. Detection of IL-13Rα2 expression and location in macrophages was performed by TaqMan PCR and fluorescent immunocytochemistry technique, respectively. Results A marked elevation of mRNA and protein expression of IL-13Rα2 was observed in mice during S. Japonicum infection. An enhanced expression of IL-13Rg2 was further demonstrated in primary macrophages of murine schistosomiasis. Conclusions IL-13Rα2 in macrophages may be a critical contributor to pathogenesis of schistosomiasis. The data highlight the potential importance of cell signaling and antifibrotic gene therapeutics in T helper 2 cell (Th2)-mediated diseases.

  6. Use of a molecular decoy to segregate transport from antigenicity in the FrpB iron transporter from Neisseria meningitidis.

    Directory of Open Access Journals (Sweden)

    Muhammad Saleem

    Full Text Available FrpB is an outer membrane transporter from Neisseria meningitidis, the causative agent of meningococcal meningitis. It is a member of the TonB-dependent transporter (TBDT family and is responsible for iron uptake into the periplasm. FrpB is subject to a high degree of antigenic variation, principally through a region of hypervariable sequence exposed at the cell surface. From the crystal structures of two FrpB antigenic variants, we identify a bound ferric ion within the structure which induces structural changes on binding which are consistent with it being the transported substrate. Binding experiments, followed by elemental analysis, verified that FrpB binds Fe(3+ with high affinity. EPR spectra of the bound Fe(3+ ion confirmed that its chemical environment was consistent with that observed in the crystal structure. Fe(3+ binding was reduced or abolished on mutation of the Fe(3+-chelating residues. FrpB orthologs were identified in other Gram-negative bacteria which showed absolute conservation of the coordinating residues, suggesting the existence of a specific TBDT sub-family dedicated to the transport of Fe(3+. The region of antigenic hypervariability lies in a separate, external sub-domain, whose structure is conserved in both the F3-3 and F5-1 variants, despite their sequence divergence. We conclude that the antigenic sub-domain has arisen separately as a result of immune selection pressure to distract the immune response from the primary transport function. This would enable FrpB to function as a transporter independently of antibody binding, by using the antigenic sub-domain as a 'molecular decoy' to distract immune surveillance.

  7. Computing Distances between Probabilistic Automata

    Directory of Open Access Journals (Sweden)

    Mathieu Tracol

    2011-07-01

    Full Text Available We present relaxed notions of simulation and bisimulation on Probabilistic Automata (PA, that allow some error epsilon. When epsilon is zero we retrieve the usual notions of bisimulation and simulation on PAs. We give logical characterisations of these notions by choosing suitable logics which differ from the elementary ones, L with negation and L without negation, by the modal operator. Using flow networks, we show how to compute the relations in PTIME. This allows the definition of an efficiently computable non-discounted distance between the states of a PA. A natural modification of this distance is introduced, to obtain a discounted distance, which weakens the influence of long term transitions. We compare our notions of distance to others previously defined and illustrate our approach on various examples. We also show that our distance is not expansive with respect to process algebra operators. Although L without negation is a suitable logic to characterise epsilon-(bisimulation on deterministic PAs, it is not for general PAs; interestingly, we prove that it does characterise weaker notions, called a priori epsilon-(bisimulation, which we prove to be NP-difficult to decide.

  8. Measuring Norwegian dialect distances using acoustic features

    NARCIS (Netherlands)

    Heeringa, Wilbert; Johnson, Keith; Gooskens, Charlotte

    2009-01-01

    Levenshtein distance has become a popular tool for measuring linguistic dialect distances, and has been applied to Irish Gaelic, Dutch, German and other dialect groups. The method, in the current state of the art, depends upon phonetic transcriptions, even when acoustic differences are used the numb

  9. Measuring Norwegian dialect distances using acoustic features

    NARCIS (Netherlands)

    Heeringa, Wilbert; Johnson, Keith; Gooskens, Charlotte

    Levenshtein distance has become a popular tool for measuring linguistic dialect distances, and has been applied to Irish Gaelic, Dutch, German and other dialect groups. The method, in the current state of the art, depends upon phonetic transcriptions, even when acoustic differences are used the

  10. Lentiviral transduction of Tar Decoy and CCR5 ribozyme into CD34+ progenitor cells and derivation of HIV-1 resistant T cells and macrophages

    Directory of Open Access Journals (Sweden)

    Rossi John

    2004-12-01

    Full Text Available Abstract Background RNA based antiviral approaches against HIV-1 are among the most promising for long-term gene therapy. These include ribozymes, aptamers (decoys, and small interfering RNAs (siRNAs. Lentiviral vectors are ideal for transduction of such inhibitory RNAs into hematopoietic stem cells due to their ability to transduce non-dividing cells and their relative refractiveness to gene silencing. The objective of this study is to introduce an HIV-1 Tar aptamer either alone or in combination with an anti-CCR5 ribozyme into CD34+ hematopoietic progenitor cells via an HIV-based lentiviral vector to derive viral resistant progeny T cells and macrophages. Results High efficiency and sustained gene transfer into CD34+ cells were achieved with lentiviral vector constructs harboring either Tar decoy or Tar decoy in combination with CCR5 ribozyme. Cells transduced with these constructs differentiated normally into T-lymphocytes in vivo in thy/liv grafts of SCID-hu mice, and into macrophages in vitro in the presence of appropriate growth factors. When challenged in vitro, the differentiated T lymphocytes and macrophages showed marked resistance against HIV-1 infection. Conclusions Viral resistant transgenic T cells and macrophages that express HIV-1 Tar aptamer either alone or in combination with an anti-CCR5 ribozyme could be obtained by lentiviral gene transduction of CD34+ progenitor cells. These results showed for the first time that expression of these anti-HIV-1 transgenes in combination do not interfere with normal thymopoiesis and thus have set the stage for their application in stem cell based gene therapy for HIV/AIDS.

  11. Therapeutic effect of intra-articular injection of ribbon-type decoy oligonucleotides for hypoxia inducible factor-1 on joint contracture in an immobilized knee animal model.

    Science.gov (United States)

    Sotobayashi, Daisuke; Kawahata, Hirohisa; Anada, Natsuki; Ogihara, Toshio; Morishita, Ryuichi; Aoki, Motokuni

    2016-08-01

    Limited range of motion (ROM) as a result of joint contracture in treatment associated with joint immobilization or motor paralysis is a critical issue. However, its molecular mechanism has not been fully clarified and a therapeutic approach is not yet established. In the present study, we investigated its molecular mechanism, focusing on the role of a transcription factor, hypoxia inducible factor-1 (HIF-1), which regulates the expression of connective tissue growth factor (CTGF) and vascular endothelial growth factor (VEGF), and evaluated the possibility of molecular therapy to inhibit HIF-1 activation by ribbon-type decoy oligonucleotides (ODNs) for HIF-1 using immobilized knee animal models. In a mouse model, ROM of the immobilized knee significantly decreased in a time-dependent manner, accompanied by synovial hypertrophy. Immunohistochemical studies suggested that CTGF and VEGF are implicated in synovial hypertrophy with fibrosis. CTGF and VEGF were up-regulated at both the mRNA and protein levels at 1 and 2 weeks after immobilization, subsequent to up-regulation of HIF-1 mRNA and transcriptional activation of HIF-1. Of importance, intra-articular transfection of decoy ODNs for HIF-1 in a rat model successfully inhibited transcriptional activation of HIF-1, followed by suppression of expression of CTGF and VEGF, resulting in attenuation of restricted ROM, whereas transfection of scrambled decoy ODNs did not. The present study demonstrates the important role of HIF-1 in the initial progression of immobilization-induced joint contracture, and indicates the possibility of molecular treatment to prevent the progression of joint contracture prior to intervention with physical therapy. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Keeping Your Distance

    Directory of Open Access Journals (Sweden)

    Glen Gatin

    2013-06-01

    Full Text Available This analysis began with inquiries into the substantive area of distance education using the classic grounded theory method. Analysis revealed a pattern of problemsolving behavior, from which the theory Keeping Your Distance emerged. The theory is an integrated set of concepts referring to the conscious and unconscious strategiesthat people use to regulate distance, physical and representative, in their everyday lives. Strategies are used to control physical, emotional, and psychological realities and to conserve personal energy in interactions with individuals and/or institutions.For all social interactions, people use a personalized algorithm of engagement that mitigates conditions and consequences and preserves optimal distance. Keeping Your Distance provides a theoretical starting point for considerations of the changing notions of distance. In part, these changes have been brought about bydevelopments in the fields of Information and Communication Technology (ICT and online social networking.

  13. Are Toll-Like Receptors and Decoy Receptors Involved in the Immunopathogenesis of Systemic Lupus Erythematosus and Lupus-Like Syndromes?

    Directory of Open Access Journals (Sweden)

    Giuliana Guggino

    2012-01-01

    Full Text Available In this paper we focus our attention on the role of two families of receptors, Toll-like receptors (TLR and decoy receptors (DcR involved in the generation of systemic lupus erythematosus (SLE and lupus-like syndromes in human and mouse models. To date, these molecules were described in several autoimmune disorders such as rheumatoid arthritis, antiphospholipids syndrome, bowel inflammation, and SLE. Here, we summarize the findings of recent investigations on TLR and DcR and their role in the immunopathogenesis of the SLE.

  14. Differentiation of AmpC beta-lactamase binders vs. decoys using classification kNN QSAR modeling and application of the QSAR classifier to virtual screening

    Science.gov (United States)

    Hsieh, Jui-Hua; Wang, Xiang S.; Teotico, Denise; Golbraikh, Alexander; Tropsha, Alexander

    2008-09-01

    The use of inaccurate scoring functions in docking algorithms may result in the selection of compounds with high predicted binding affinity that nevertheless are known experimentally not to bind to the target receptor. Such falsely predicted binders have been termed `binding decoys'. We posed a question as to whether true binders and decoys could be distinguished based only on their structural chemical descriptors using approaches commonly used in ligand based drug design. We have applied the k-Nearest Neighbor ( kNN) classification QSAR approach to a dataset of compounds characterized as binders or binding decoys of AmpC beta-lactamase. Models were subjected to rigorous internal and external validation as part of our standard workflow and a special QSAR modeling scheme was employed that took into account the imbalanced ratio of inhibitors to non-binders (1:4) in this dataset. 342 predictive models were obtained with correct classification rate (CCR) for both training and test sets as high as 0.90 or higher. The prediction accuracy was as high as 100% (CCR = 1.00) for the external validation set composed of 10 compounds (5 true binders and 5 decoys) selected randomly from the original dataset. For an additional external set of 50 known non-binders, we have achieved the CCR of 0.87 using very conservative model applicability domain threshold. The validated binary kNN QSAR models were further employed for mining the NCGC AmpC screening dataset (69653 compounds). The consensus prediction of 64 compounds identified as screening hits in the AmpC PubChem assay disagreed with their annotation in PubChem but was in agreement with the results of secondary assays. At the same time, 15 compounds were identified as potential binders contrary to their annotation in PubChem. Five of them were tested experimentally and showed inhibitory activities in millimolar range with the highest binding constant Ki of 135 μM. Our studies suggest that validated QSAR models could complement

  15. Numerical distance protection

    CERN Document Server

    Ziegler, Gerhard

    2011-01-01

    Distance protection provides the basis for network protection in transmission systems and meshed distribution systems. This book covers the fundamentals of distance protection and the special features of numerical technology. The emphasis is placed on the application of numerical distance relays in distribution and transmission systems.This book is aimed at students and engineers who wish to familiarise themselves with the subject of power system protection, as well as the experienced user, entering the area of numerical distance protection. Furthermore it serves as a reference guide for s

  16. Distance probes of dark energy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, A. G.; Padmanabhan, N.; Aldering, G.; Allen, S. W.; Baltay, C.; Cahn, R. N.; D’Andrea, C. B.; Dalal, N.; Dawson, K. S.; Denney, K. D.; Eisenstein, D. J.; Finley, D. A.; Freedman, W. L.; Ho, S.; Holz, D. E.; Kasen, D.; Kent, S. M.; Kessler, R.; Kuhlmann, S.; Linder, E. V.; Martini, P.; Nugent, P. E.; Perlmutter, S.; Peterson, B. M.; Riess, A. G.; Rubin, D.; Sako, M.; Suntzeff, N. V.; Suzuki, N.; Thomas, R. C.; Wood-Vasey, W. M.; Woosley, S. E.

    2015-03-01

    This document presents the results from the Distances subgroup of the Cosmic Frontier Community Planning Study (Snowmass 2013). We summarize the current state of the field as well as future prospects and challenges. In addition to the established probes using Type Ia supernovae and baryon acoustic oscillations, we also consider prospective methods based on clusters, active galactic nuclei, gravitational wave sirens and strong lensing time delays.

  17. Distance Probes of Dark Energy

    CERN Document Server

    Kim, A; Aldering, G; Allen, S; Baltay, C; Cahn, R; D'Andrea, C; Dalal, N; Dawson, K; Denney, K; Eisenstein, D; Finley, D; Freedman, W; Ho, S; Holz, D; Kent, A; Kasen, D; Kessler, R; Kuhlmann, S; Linder, E; Martini, P; Nugent, P; Perlmutter, S; Peterson, B; Riess, A; Rubin, D; Sako, M; Suntzeff, N; Suzuki, N; Thomas, R; Wood-Vasey, W M; Woosley, S

    2013-01-01

    This document presents the results from the Distances subgroup of the Cosmic Frontier Community Planning Study (Snowmass 2013). We summarize the current state of the field as well as future prospects and challenges. In addition to the established probes using Type IA supernovae and baryon acoustic oscillations, we also consider prospective methods based on clusters, active galactic nuclei, gravitational wave sirens and strong lensing time delays.

  18. Kilohertz QPOs, spectral state transitions and the distance to the neutron star X-ray transient IGR J17473-2721

    DEFF Research Database (Denmark)

    Altamirano, D.; Galloway, D.; Chenevez, Jérôme

    2008-01-01

    We report on RXTE monitoring observations of the transient X-ray binary IGR J17473-2721 since the beginning of its latest outburst on March 26th, 2008 (see ATEL #1445, #1459, #1460, #1461 and #1468). IGR J17473-2721 reached a maximum unabsorbed flux of ~1.30E-8 ergs cm-2 s-1 (2-10 keV, assuming n......H=3.8e22cm-2, ATEL #1459) on June 22nd, and has been steadily decreasing since. The X-ray spectral state (based on the X-ray colors in the 2-16 keV band) has switched from hard to soft and back to hard. These state changes are also evident from the Swift/BAT Hard X-ray monitoring light curves. During...

  19. Normalized information distance

    NARCIS (Netherlands)

    Vitányi, P.M.B.; Balbach, F.J.; Cilibrasi, R.L.; Li, M.; Emmert-Streib, F.; Dehmer, M.

    2009-01-01

    The normalized information distance is a universal distance measure for objects of all kinds. It is based on Kolmogorov complexity and thus uncomputable, but there are ways to utilize it. First, compression algorithms can be used to approximate the Kolmogorov complexity if the objects have a string

  20. Normalized information distance

    NARCIS (Netherlands)

    Vitányi, P.M.B.; Balbach, F.J.; Cilibrasi, R.L.; Li, M.

    2008-01-01

    The normalized information distance is a universal distance measure for objects of all kinds. It is based on Kolmogorov complexity and thus uncomputable, but there are ways to utilize it. First, compression algorithms can be used to approximate the Kolmogorov complexity if the objects have a string

  1. Incremental Distance Transforms (IDT)

    NARCIS (Netherlands)

    Schouten, Theo E.; van den Broek, Egon; Erçil, A.; Çetin, M.; Boyer, K.; Lee, S.-W.

    2010-01-01

    A new generic scheme for incremental implementations of distance transforms (DT) is presented: Incremental Distance Transforms (IDT). This scheme is applied on the cityblock, Chamfer, and three recent exact Euclidean DT (E2DT). A benchmark shows that for all five DT, the incremental implementation r

  2. ORDERED WEIGHTED DISTANCE MEASURE

    Institute of Scientific and Technical Information of China (English)

    Zeshui XU; Jian CHEN

    2008-01-01

    The aim of this paper is to develop an ordered weighted distance (OWD) measure, which is thegeneralization of some widely used distance measures, including the normalized Hamming distance, the normalized Euclidean distance, the normalized geometric distance, the max distance, the median distance and the min distance, etc. Moreover, the ordered weighted averaging operator, the generalized ordered weighted aggregation operator, the ordered weighted geometric operator, the averaging operator, the geometric mean operator, the ordered weighted square root operator, the square root operator, the max operator, the median operator and the min operator axe also the special cases of the OWD measure. Some methods depending on the input arguments are given to determine the weights associated with the OWD measure. The prominent characteristic of the OWD measure is that it can relieve (or intensify) the influence of unduly large or unduly small deviations on the aggregation results by assigning them low (or high) weights. This desirable characteristic makes the OWD measure very suitable to be used in many actual fields, including group decision making, medical diagnosis, data mining, and pattern recognition, etc. Finally, based on the OWD measure, we develop a group decision making approach, and illustrate it with a numerical example.

  3. Duty and Distance

    NARCIS (Netherlands)

    C. Binder (C.); C. Heilmann (Conrad)

    2017-01-01

    markdownabstractEver since the publication of Peter Singer’s article ‘‘Famine, Affluence, and Morality’’ has the question of whether the (geographical) distance to people in need affects our moral duties towards them been a hotly debated issue. Does geographical distance affect our moral duties?

  4. Biomechanics of Distance Running.

    Science.gov (United States)

    Cavanagh, Peter R., Ed.

    Contributions from researchers in the field of running mechanics are included in the 13 chapters of this book. The following topics are covered: (1) "The Mechanics of Distance Running: A Historical Perspective" (Peter Cavanagh); (2) "Stride Length in Distance Running: Velocity, Body Dimensions, and Added Mass Effects" (Peter Cavanagh, Rodger…

  5. Distance Learning Environment Demonstration.

    Science.gov (United States)

    1996-11-01

    The Distance Learning Environment Demonstration (DLED) was a comparative study of distributed multimedia computer-based training using low cost high...measurement. The DLED project provides baseline research in the effective use of distance learning and multimedia communications over a wide area ATM/SONET

  6. Duty and Distance

    NARCIS (Netherlands)

    C. Binder (C.); C. Heilmann (Conrad)

    2017-01-01

    markdownabstractEver since the publication of Peter Singer’s article ‘‘Famine, Affluence, and Morality’’ has the question of whether the (geographical) distance to people in need affects our moral duties towards them been a hotly debated issue. Does geographical distance affect our moral

  7. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states.

    Directory of Open Access Journals (Sweden)

    Leslie A Reperant

    likelihood of migratory take-off, this may favor the spread of HPAIV H5N1 by migratory birds over long distances.

  8. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states.

    Science.gov (United States)

    Reperant, Leslie A; van de Bildt, Marco W G; van Amerongen, Geert; Buehler, Debbie M; Osterhaus, Albert D M E; Jenni-Eiermann, Susi; Piersma, Theunis; Kuiken, Thijs

    2011-01-01

    migratory take-off, this may favor the spread of HPAIV H5N1 by migratory birds over long distances.

  9. Estimating distances from parallaxes

    Science.gov (United States)

    Astraatmadja, Tri L.; Bailer-Jones, Coryn

    2017-01-01

    In astrometric surveys such as Gaia and LSST, parallaxes will be measured for about a billion stars, but zero distances will be measured. Distances must be inferred from the parallaxes, and the common inference practice is by inverting the parallax. This, however, is only appropriate when there is no noise present. As noise will always be present and most stars in future surveys will have non-negligible fractional parallax uncertainties, we must treat distance estimation as an inference problem. The usage of prior assumptions become unavoidable. In this talk I will present a method on how to infer distances using Bayesian inference. Three minimalists, isotropic priors are used, as well an anisotropic prior derived from the observability of stars in a Milky Way model. The performance of these priors are investigated using a simulated Gaia-like catalogue. Recent results of distance estimation using the parallaxes of 2 million Gaia DR1 stars will also be discussed.

  10. Normalized Information Distance

    CERN Document Server

    Vitanyi, Paul M B; Cilibrasi, Rudi L; Li, Ming

    2008-01-01

    The normalized information distance is a universal distance measure for objects of all kinds. It is based on Kolmogorov complexity and thus uncomputable, but there are ways to utilize it. First, compression algorithms can be used to approximate the Kolmogorov complexity if the objects have a string representation. Second, for names and abstract concepts, page count statistics from the World Wide Web can be used. These practical realizations of the normalized information distance can then be applied to machine learning tasks, expecially clustering, to perform feature-free and parameter-free data mining. This chapter discusses the theoretical foundations of the normalized information distance and both practical realizations. It presents numerous examples of successful real-world applications based on these distance measures, ranging from bioinformatics to music clustering to machine translation.

  11. Knockdown of Decoy Receptor 3 Impairs Growth and Invasiveness of Hepatocellular Carcinoma Cell Line of HepG2

    Institute of Scientific and Technical Information of China (English)

    Xiao-Na Zhou; Guang-Ming Li; Ying-Chen Xu; Tuan-Jie Zhao; Ji-Xiang Wu

    2016-01-01

    Background:Decoy receptor 3 (DcR3) binds to Fas ligand (FasL) and inhibits FasL-induced apoptosis.The receptor is overexpressed in hepatocellular carcinoma (HCC),and it is associated with the growth and metastatic spread of tumors.DcR3 holds promises as a new target for the treatment of HCC,but little is known regarding the molecular mechanisms underlying the oncogenic properties of DcR3.The present work,therefore,examined the role of DcR3 in regulating the growth and invasive property of liver cancer cell HepG2.Methods:HepG2 cells were stably transfected with lentivirus-based short hairpin RNA vector targeting DcR3.After the knockdown of DcR3 was confirmed,cell proliferation,clone formation,ability of migrating across transwell membrane,and wound healing were assessed in vitro.Matrix metalloproteinase-9 (MMP 9) and vascular epithelial growth factor (VEGF)-C and D expressions of the DcR3 knockdown were also studied.Comparisons between multiple groups were done using one-way analysis of variance (ANOVA),while pairwise comparisons were performed using Student's t test.P < 0.05 was regarded statistically significant.Results:DcR3 was overexpressed in HepG2 compared to other HCC cell lines and normal hepatocyte Lo-2.Stable knockdown of DcR3 slowed down the growth of HepG2 (P < 0.05) and reduced the number of clones formed by 50% compared to those without DcR3 knockdown (P < 0.05).The knockdown also reduced the migration of HepG2 across transwell matrix membrane by five folds compared to the control (P < 0.05) and suppressed the closure of scratch wound (P < 0.05).In addition,the messenger RNA levels of MMP 9,VEGF-C,and VEGF-D were significantly suppressed by DcR3 knockdown by 90% when compared with the mock control (P < 0.05).Conclusions:Loss of DcR3 impaired the growth and invasive property of HCC cell line of HepG2.Targeting DcR3 may be a potential therapeutic approach for the treatment of HCC.

  12. Decoy receptor 3 suppresses FasL-induced apoptosis via ERK1/2 activation in pancreatic cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yi; Li, Dechun; Zhao, Xin; Song, Shiduo; Zhang, Lifeng; Zhu, Dongming [Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Wang, Zhenxin [Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Chen, Xiaochen [Department of Pathology, The Obstetrics & Gynecology Hospital of Fudan University, Shanghai 200090 (China); Zhou, Jian, E-mail: zhoujian20150602@126.com [Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China)

    2015-08-07

    Resistance to Fas Ligand (FasL) mediated apoptosis plays an important role in tumorigenesis. Decoy receptor 3 (DcR3) is reported to interact with FasL and is overexpressed in some malignant tumors. We sought to investigate the role of DcR3 in resistance to FasL in pancreatic cancer. We compared expression of apoptosis related genes between FasL-resistant SW1990 and FasL-sensitive Patu8988 pancreatic cell lines by microarray analysis. We explored the impact of siRNA knockdown of, or exogenous supplementation with, DcR3 on FasL-induced cell growth inhibition in pancreatic cancer cell lines and expression of proteins involved in apoptotic signaling. We assessed the level of DcR3 protein and ERK1/2 phosphorylation in tumor and non-tumor tissue samples of 66 patients with pancreatic carcinoma. RNAi knockdown of DcR3 expression in SW1990 cells reduced resistance to FasL-induced apoptosis, and supplementation of Patu8988 with rDcR3 had the opposite effect. RNAi knockdown of DcR3 in SW1990 cells elevated expression of caspase 3, 8 and 9, and reduced ERK1/2 phosphorylation (P < 0.05), but did not alter phosphorylated-Akt expression. 47 tumor tissue specimens, but only 15 matched non-tumor specimens stained for DcR3 (χ{sup 2} = 31.1447, P < 0.001). The proliferation index of DcR3 positive specimens (14.26  ±  2.67%) was significantly higher than that of DcR3 negative specimens (43.58  ±  7.88%, P < 0.01). DcR3 expression positively correlated with p-ERK1/2 expression in pancreatic cancer tissues (r = 0.607, P < 0.001). DcR3 enhances ERK1/2 phosphorylation and opposes FasL signaling in pancreatic cancer cells. - Highlights: • We investigated the role of DcR3 in FasL resistance in pancreatic cancer. • Knockdown of DcR3 in SW1990 cells reduced resistance to FasL-induced apoptosis. • DcR3 knockdown also elevated caspase expression, and reduced ERK1/2 phosphorylation. • Tumor and non-tumor tissues were collected from 66 pancreatic carcinoma patients

  13. A tissue microarray study of toll-like receptor 4, decoy receptor 3, and external signal regulated kinase 1/2 expressions in astrocytoma.

    Science.gov (United States)

    Lin, Chih-Kung; Ting, Chun-Chieh; Tsai, Wen-Chiuan; Chen, Yuan-Wu; Hueng, Dueng-Yuan

    2016-01-01

    Decoy receptor 3 (DcR3) functions as a death decoy inhibiting apoptosis mediated by the tumor necrosis factor receptor family. It is highly expressed in many tumors and its expression can be regulated by the MAPK/ERK signaling pathway and ERK is a vital member of this pathway. Toll-like receptor 4 (TLR4) is expressed on immune cells. Increased TLR4 expression has been associated with various types of cancers. The study was conducted to investigate the expression of DcR3, ERK1/2, and TLR4 in astrocytomas and evaluate if they are validating markers for discriminating glioblastoma from anaplastic astrocytoma in limited surgical specimen. Expression of DcR3, ERK1/2, and TLR4 was determined by immunohistochemical staining of tissue microarray from 48 paraffin-embedded tissues. A binary logistic regression method was used to generate functions that discriminate between anaplastic astrocytomas and glioblastomas. The expression of TLR4 and DcR3 was significantly higher in glioblastomas than in anaplastic astrocytomas. DcR3 could discriminate anaplastic astrocytomas from glioblastomas with high sensitivity (93.8%), specificity (90%), and accuracy (92.3%). Our results suggest that DcR3 may be a useful marker for discriminating anaplastic astrocytomas from glioblastomas.

  14. HIV infection enhances TRAIL-induced cell death in macrophage by down-regulating decoy receptor expression and generation of reactive oxygen species.

    Directory of Open Access Journals (Sweden)

    Dan-Ming Zhu

    Full Text Available BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL could induce apoptosis of HIV-1-infected monocyte-derived macrophage (MDM, but the molecular mechanisms are not well understood. METHODOLOGY/PRINCIPAL FINDINGS: By using an HIV-1 Env-pseudotyped virus (HIV-1 PV-infected MDM cell model we demonstrate that HIV-1 PV infection down-regulates the expression of TRAIL decoy receptor 1 (DcR1 and 2 (DcR2, and cellular FLICE-inhibitory protein (c-FLIP, but dose not affect the expression of death receptor 4 and 5 (DR4, DR5, and Bcl-2 family members in MDM cells. Furthermore, recombinant soluble TRAIL and an agonistic anti-DR5 antibody, AD5-10, treatment stimulates reactive oxygen species (ROS generation and JNK phosphorylation. CONCLUSIONS/SIGNIFICANCE: HIV infection facilitates TRIAL-induced cell death in MDM by down-regulating the expression of TRAIL decoy receptors and intracellular c-FLIP. Meanwhile, the agonistic anti-DR5 antibody, AD5-10, induces apoptosis synergistically with TRAIL in HIV-1-infected cells. ROS generation and JNK phosphorylation are involved in this process. These findings potentiate clinical usage of the combination of TRAIL and AD5-10 in eradication of HIV-infected macrophage and AIDS.

  15. Estimating distances from parallaxes

    CERN Document Server

    Bailer-Jones, C A L

    2015-01-01

    Astrometric surveys such as Gaia and LSST will measure parallaxes for hundreds of millions of stars. Yet they will not measure a single distance. Rather, a distance must be estimated from a parallax. In this didactic article, I show that doing this is not trivial once the fractional parallax error is larger than about 20%, which will be the case for about 80% of stars in the Gaia catalogue. Estimating distances is an inference problem in which the use of prior assumptions is unavoidable. I investigate the properties and performance of various priors and examine their implications. A supposed uninformative uniform prior in distance is shown to give very poor distance estimates (large bias and variance). Any prior with a sharp cut-off at some distance has similar problems. The choice of prior depends on the information one has available - and is willing to use - concerning, for example, the survey and the Galaxy. I demonstrate that a simple prior which decreases asymptotically to zero at infinite distance has g...

  16. Distance software: design and analysis of distance sampling surveys for estimating population size.

    Science.gov (United States)

    Thomas, Len; Buckland, Stephen T; Rexstad, Eric A; Laake, Jeff L; Strindberg, Samantha; Hedley, Sharon L; Bishop, Jon Rb; Marques, Tiago A; Burnham, Kenneth P

    2010-02-01

    1.Distance sampling is a widely used technique for estimating the size or density of biological populations. Many distance sampling designs and most analyses use the software Distance.2.We briefly review distance sampling and its assumptions, outline the history, structure and capabilities of Distance, and provide hints on its use.3.Good survey design is a crucial prerequisite for obtaining reliable results. Distance has a survey design engine, with a built-in geographic information system, that allows properties of different proposed designs to be examined via simulation, and survey plans to be generated.4.A first step in analysis of distance sampling data is modelling the probability of detection. Distance contains three increasingly sophisticated analysis engines for this: conventional distance sampling, which models detection probability as a function of distance from the transect and assumes all objects at zero distance are detected; multiple-covariate distance sampling, which allows covariates in addition to distance; and mark-recapture distance sampling, which relaxes the assumption of certain detection at zero distance.5.All three engines allow estimation of density or abundance, stratified if required, with associated measures of precision calculated either analytically or via the bootstrap.6.Advanced analysis topics covered include the use of multipliers to allow analysis of indirect surveys (such as dung or nest surveys), the density surface modelling analysis engine for spatial and habitat modelling, and information about accessing the analysis engines directly from other software.7.Synthesis and applications. Distance sampling is a key method for producing abundance and density estimates in challenging field conditions. The theory underlying the methods continues to expand to cope with realistic estimation situations. In step with theoretical developments, state-of-the-art software that implements these methods is described that makes the methods

  17. MOTIVATION FOR DISTANCE EDUCATION

    Directory of Open Access Journals (Sweden)

    R zvan TEF NESCU

    2009-10-01

    Full Text Available Beginning with the 1980’s the new information, communication and computer based technologies stimulated the development of the distance education. In Romania the universities adapted rapidly to this type of learning that became an important financing source for most of them. In this article we approach the causes of attraction for the distance education. For this purpose we use an investigation we did on a group of students at Distance Education including interviews regarding their reasons for choosing this type of learning.

  18. Camouflage, Concealment, and Decoys

    Science.gov (United States)

    2010-11-26

    normal unit supply channels (see appendix E). The LCSS reduces a vehicle’s visual and radar signatures. Stainless steel fibers in the LCSS material...components and the instructions for assembling LCSS structures for different sizes of equipment.) VEGETATION 3-65. Use branches and vines to temporarily...same shape and thermal signature as the target it is meant to conceal.  Ensure that the lines between support poles are gently sloped so that the

  19. Distance learning perspectives.

    Science.gov (United States)

    Pandza, Haris; Masic, Izet

    2013-01-01

    The development of modern technology and the Internet has enabled the explosive growth of distance learning. distance learning is a process that is increasingly present in the world. This is the field of education focused on educating students who are not physically present in the traditional classrooms or student's campus. described as a process where the source of information is separated from the students in space and time. If there are situations that require the physical presence of students, such as when a student is required to physically attend the exam, this is called a hybrid form of distance learning. This technology is increasingly used worldwide. The Internet has become the main communication channel for the development of distance learning.

  20. Learning Pullback HMM Distances.

    Science.gov (United States)

    Cuzzolin, Fabio; Sapienza, Michael

    2014-07-01

    Recent work in action recognition has exposed the limitations of methods which directly classify local features extracted from spatio-temporal video volumes. In opposition, encoding the actions' dynamics via generative dynamical models has a number of attractive features: however, using all-purpose distances for their classification does not necessarily deliver good results. We propose a general framework for learning distance functions for generative dynamical models, given a training set of labelled videos. The optimal distance function is selected among a family of pullback ones, induced by a parametrised automorphism of the space of models. We focus here on hidden Markov models and their model space, and design an appropriate automorphism there. Experimental results are presented which show how pullback learning greatly improves action recognition performances with respect to base distances.

  1. Deciphering the Distance between Distance Education and Working Professionals in Difficult Geographies

    Science.gov (United States)

    Pandey, Jatin; Singh, Manjari

    2015-01-01

    This study investigates the factors that draw working professionals towards distance education programs, and the factors that sustain their distance education experience. The study is conducted in difficult terrains of Uttarakhand, a hilly state in India which helps us investigate the phenomenon in difficult geographies. Through interviews of ten…

  2. Presence at a distance.

    Science.gov (United States)

    Haddouk, Lise

    2015-01-01

    Nowadays in the context of the cyberculture, computer-mediated inter-subjective relationships are part of our everyday lives, in both the professional and personal spheres, and for all age groups. In the clinical field, many applications have been developed to facilitate the exchange of informations and mediate the relationship between patient and therapist. In psychology, more or less immersive technologies are used, to encourage the feeling of presence among the users, and to trigger certain psychological processes. In our research, we have explored the remote clinical interview through videoconferencing, with the development and utilisation of the iPSY platform, totally focused on this objective. In this context, we have considered the notion of intersubjectivity, despite the physical absence. This research is leading us today to envision the notions of distance and presence, and possibly to redefine them. Thus, can we still oppose physical distance to psychological distance? Can we still affirm that the physical absence does not permit a psychological co-presence in certain interactions, like this observed in video interviews? The results show that the psychological processes, activated in this context, are similar to those observed in "traditional" clinical consults between the patient and the therapist. However, certain specifics have led us to consider the concept of distance, here influenced by the framework, and to observe its effects. This distance could possibly constitute a therapeutic lever for some patients, notably for those who have difficulties establishing the right psychological distance in their relationships with others. According to these results, can "distance" still be opposed to "presence", or could it be re-defined? This also opens up questions on the more general concept of digital relationships, and the definition of their specificities.

  3. Distance learning for similarity estimation

    NARCIS (Netherlands)

    Yu, J.; Amores, J.; Sebe, N.; Radeva, P.; Tian, Q.

    2008-01-01

    In this paper, we present a general guideline to find a better distance measure for similarity estimation based on statistical analysis of distribution models and distance functions. A new set of distance measures are derived from the harmonic distance, the geometric distance, and their generalized

  4. Hybrid Long-Distance Entanglement Distribution Protocol

    DEFF Research Database (Denmark)

    Brask, J.B.; Rigas, I.; Polzik, E.S.;

    2010-01-01

    We propose a hybrid (continuous-discrete variable) quantum repeater protocol for long-distance entanglement distribution. Starting from states created by single-photon detection, we show how entangled coherent state superpositions can be generated by means of homodyne detection. We show that near...

  5. Stereoscopic distance perception

    Science.gov (United States)

    Foley, John M.

    1989-01-01

    Limited cue, open-loop tasks in which a human observer indicates distances or relations among distances are discussed. By open-loop tasks, it is meant tasks in which the observer gets no feedback as to the accuracy of the responses. What happens when cues are added and when the loop is closed are considered. The implications of this research for the effectiveness of visual displays is discussed. Errors in visual distance tasks do not necessarily mean that the percept is in error. The error could arise in transformations that intervene between the percept and the response. It is argued that the percept is in error. It is also argued that there exist post-perceptual transformations that may contribute to the error or be modified by feedback to correct for the error.

  6. Distances to Dark Clouds: Comparing Extinction Distances to Maser Parallax Distances

    CERN Document Server

    Foster, Jonathan B; Benjamin, Robert A; Hoare, Melvin G; Jackson, James M

    2012-01-01

    We test two different methods of using near-infrared extinction to estimate distances to dark clouds in the first quadrant of the Galaxy using large near infrared (2MASS and UKIDSS) surveys. VLBI parallax measurements of masers around massive young stars provide the most direct and bias-free measurement of the distance to these dark clouds. We compare the extinction distance estimates to these maser parallax distances. We also compare these distances to kinematic distances, including recent re-calibrations of the Galactic rotation curve. The extinction distance methods agree with the maser parallax distances (within the errors) between 66% and 100% of the time (depending on method and input survey) and between 85% and 100% of the time outside of the crowded Galactic center. Although the sample size is small, extinction distance methods reproduce maser parallax distances better than kinematic distances; furthermore, extinction distance methods do not suffer from the kinematic distance ambiguity. This validatio...

  7. Sets avoiding integral distances

    CERN Document Server

    Kurz, Sascha

    2012-01-01

    We study open point sets in Euclidean spaces $\\mathbb{R}^d$ without a pair of points an integral distance apart. By a result of Furstenberg, Katznelson, and Weiss such sets must be of Lebesgue upper density zero. We are interested in how large such sets can be in $d$-dimensional volume. We determine the lower and upper bounds for the volumes of the sets in terms of the number of their connected components and dimension, and also give some exact values. Our problem can be viewed as a kind of inverse to known problems on sets with pairwise rational or integral distances.

  8. Distance Teaching on Bornholm

    DEFF Research Database (Denmark)

    Hansen, Finn J. S.; Clausen, Christian

    2001-01-01

    The case study represents an example of a top-down introduction of distance teaching as part of Danish trials with the introduction of multimedia in education. The study is concerned with the background, aim and context of the trial as well as the role and working of the technology and the organi......The case study represents an example of a top-down introduction of distance teaching as part of Danish trials with the introduction of multimedia in education. The study is concerned with the background, aim and context of the trial as well as the role and working of the technology...

  9. 磁力床垫对中长跑运动员心境状态和睡眠质量的影响%Effect of Magnetic Mattress on Mental State and Sleep Quality of Middle and Long Distance Runners

    Institute of Scientific and Technical Information of China (English)

    徐文泉; 王智; 冯玲

    2012-01-01

    为检测磁力床垫对中长跑运动员心境状态和睡眠质量的影响,采用文献资料法、实验比较法、问卷调查法和数理统计法,以现役29名中长跑运动员为研究对象,其中15名为实验组(使用磁力床垫)、14名为对照组(使用普通床垫),对他们大运动量训练后的心境状态和睡眠质量展开调查,结果表明:(1)使用磁力床垫的实验组在调节心境状态方面明显优于使用普通床垫的对照组,它能够明显缓解运动员疲劳、恢复精力、抚平慌乱情绪和有效处理纷乱情绪;(2)磁力床垫在中长跑运动员提高睡眠质量方面,主要体现在能够延长睡眠的有效时间。%In order to test the effect of magnetic mattress on mental state and sleep quality of middle and long distance runners, the authors surveyed the athletes' mental state and sleep quality after intensive training by the methods of literature study, experimental comparison, questionnaire and statistics. 29 middle-distance runners were chosen as the subjects, among whom 15 were put into experiment group (using magnetic mattress) and 14 in control group (using ordinary mattress). The result shows that the mental state adjustment of the experiment group is obviously better than that of the control group. Magnetic mattress can help athletes to alleviate fatigue, recover energy and ease their mood. In terms of sleep quality improvement, magnetic mattress may effectively prolong the athletes' sleep time.

  10. Distances to star forming regions

    CERN Document Server

    Loinard, Laurent

    2014-01-01

    The determination of accurate distances to star-forming regions are discussed in the broader historical context of astronomical distance measurements. We summarize recent results for regions within 1 kpc and present perspectives for the near and more distance future.

  11. Signaling Over Distances.

    Science.gov (United States)

    Saito, Atsushi; Cavalli, Valeria

    2016-02-01

    Neurons are extremely polarized cells. Axon lengths often exceed the dimension of the neuronal cell body by several orders of magnitude. These extreme axonal lengths imply that neurons have mastered efficient mechanisms for long distance signaling between soma and synaptic terminal. These elaborate mechanisms are required for neuronal development and maintenance of the nervous system. Neurons can fine-tune long distance signaling through calcium wave propagation and bidirectional transport of proteins, vesicles, and mRNAs along microtubules. The signal transmission over extreme lengths also ensures that information about axon injury is communicated to the soma and allows for repair mechanisms to be engaged. This review focuses on the different mechanisms employed by neurons to signal over long axonal distances and how signals are interpreted in the soma, with an emphasis on proteomic studies. We also discuss how proteomic approaches could help further deciphering the signaling mechanisms operating over long distance in axons. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Weighted Feature Distance

    DEFF Research Database (Denmark)

    Ortiz-Arroyo, Daniel; Yazdani, Hossein

    2017-01-01

    The accuracy of machine learning methods for clustering depends on the optimal selection of similarity functions. Conventional distance functions for the vector space might cause an algorithm to being affected by some dominant features that may skew its final results. This paper introduces a flexib...

  13. Encyclopedia of Distance Learning

    Science.gov (United States)

    Howard, Caroline, Ed.; Boettecher, Judith, Ed.; Justice, Lorraine, Ed.; Schenk, Karen, Ed.; Rogers, Patricia, Ed.; Berg, Gary, Ed.

    2005-01-01

    The innovations in computer and communications technologies combined with on-going needs to deliver educational programs to students regardless of their physical locations, have lead to the innovation of distance education programs and technologies. To keep up with recent developments in both areas of technologies and techniques related to…

  14. Accreditation of Distance Learning

    Science.gov (United States)

    Demirel, Ergün

    2016-01-01

    The higher education institutes aspire to gain reputation of quality having accreditation from internationally recognized awarding bodies. The accreditation leads and provides quality assurance for education. Although distance learning becomes a significant part of the education system in the 21st century, there is still a common opinion that the…

  15. Rapport in Distance Education

    Science.gov (United States)

    Murphy, Elizabeth; Rodriguez-Manzanares, Maria A.

    2012-01-01

    Rapport has been recognized as important in learning in general but little is known about its importance in distance education (DE). The study we report on in this paper provides insights into the importance of rapport in DE as well as challenges to and indicators of rapport-building in DE. The study relied on interviews with 42 Canadian…

  16. Misconceptions of Astronomical Distances

    Science.gov (United States)

    Miller, Brian W.; Brewer, William F.

    2010-01-01

    Previous empirical studies using multiple-choice procedures have suggested that there are misconceptions about the scale of astronomical distances. The present study provides a quantitative estimate of the nature of this misconception among US university students by asking them, in an open-ended response format, to make estimates of the distances…

  17. On Properties of the Generalized Wasserstein Distance

    Science.gov (United States)

    Piccoli, Benedetto; Rossi, Francesco

    2016-12-01

    The Wasserstein distances W p ( p {≥q} 1), defined in terms of a solution to the Monge-Kantorovich problem, are known to be a useful tool to investigate transport equations. In particular, the Benamou-Brenier formula characterizes the square of the Wasserstein distance W 2 as the infimum of the kinetic energy, or action functional, of all vector fields transporting one measure to the other. Another important property of the Wasserstein distances is the Kantorovich-Rubinstein duality, stating the equality between the distance W 1( μ, ν) of two probability measures μ, ν and the supremum of the integrals in d( μ - ν) of Lipschitz continuous functions with Lipschitz constant bounded by one. An intrinsic limitation of Wasserstein distances is the fact that they are defined only between measures having the same mass. To overcome such a limitation, we recently introduced the generalized Wasserstein distances {W_p^{a,b}}, defined in terms of both the classical Wasserstein distance W p and the total variation (or L 1) distance, see (Piccoli and Rossi in Archive for Rational Mechanics and Analysis 211(1):335-358, 2014). Here p plays the same role as for the classic Wasserstein distance, while a and b are weights for the transport and the total variation term. In this paper we prove two important properties of the generalized Wasserstein distances: (1) a generalized Benamou-Brenier formula providing the equality between {W_2^{a,b}} and the supremum of an action functional, which includes a transport term (kinetic energy) and a source term; (2) a duality à la Kantorovich-Rubinstein establishing the equality between {W_1^{1,1}} and the flat metric.

  18. Measurement-device-independent quantum key distribution with source state errors and statistical fluctuation

    Science.gov (United States)

    Jiang, Cong; Yu, Zong-Wen; Wang, Xiang-Bin

    2017-03-01

    We show how to calculate the secure final key rate in the four-intensity decoy-state measurement-device-independent quantum key distribution protocol with both source errors and statistical fluctuations with a certain failure probability. Our results rely only on the range of only a few parameters in the source state. All imperfections in this protocol have been taken into consideration without assuming any specific error patterns of the source.

  19. Fuzzy clustering with Minkowski distance

    NARCIS (Netherlands)

    P.J.F. Groenen (Patrick); U. Kaymak (Uzay); J.M. van Rosmalen (Joost)

    2006-01-01

    textabstractDistances in the well known fuzzy c-means algorithm of Bezdek (1973) are measured by the squared Euclidean distance. Other distances have been used as well in fuzzy clustering. For example, Jajuga (1991) proposed to use the L_1-distance and Bobrowski and Bezdek (1991) also used the L_inf

  20. The sound of distance.

    Science.gov (United States)

    Rabaglia, Cristina D; Maglio, Sam J; Krehm, Madelaine; Seok, Jin H; Trope, Yaacov

    2016-07-01

    Human languages may be more than completely arbitrary symbolic systems. A growing literature supports sound symbolism, or the existence of consistent, intuitive relationships between speech sounds and specific concepts. Prior work establishes that these sound-to-meaning mappings can shape language-related judgments and decisions, but do their effects generalize beyond merely the linguistic and truly color how we navigate our environment? We examine this possibility, relating a predominant sound symbolic distinction (vowel frontness) to a novel associate (spatial proximity) in five studies. We show that changing one vowel in a label can influence estimations of distance, impacting judgment, perception, and action. The results (1) provide the first experimental support for a relationship between vowels and spatial distance and (2) demonstrate that sound-to-meaning mappings have outcomes that extend beyond just language and can - through a single sound - influence how we perceive and behave toward objects in the world. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Tolman's Luminosity-Distance, Poincare's Light-Distance and Cayley-Klein's Hyperbolic Distance

    CERN Document Server

    Pierseaux, Yves

    2009-01-01

    We deduce Tolman's formula of luminosity-distance in Cosmology from Poincare's definition of light-distance with Lorentz Transformation (LT).In Minkowskian metric, if distance is proper time (as it is often argued) then light-distance must be also the shortest distance, like proper duration (unlike Einstein's longest length within rest system). By introducing Poincare's proper light-distance in Einstein's basic synchronization we deduce a dilated distance between observer and receding mirror (with relativistic Doppler factor). Such a distance corresponds not to an Euclidean distance (Einstein's rigid rod) but to an Hyperbolic distance (Cayley-Klein) with a Lobatchevskian Horizon. From a basic proportionality hyperbolic distance-velocity, we deduce the law of Hubble. By following Penrose's Lobatchevskian representation of LT, we transform Special Relativity (SR) into an Hyperbolic Cosmological Relativity (HCR). by using only the LT but the whole LT. In Hyperbolic Rotation motion (basic active LT or Einstein's ...

  2. Application of Distance of Information-state Transition Theory on Usability Testing of University Portal%信息距离理论在高校门户网站易用性测度中的应用

    Institute of Scientific and Technical Information of China (English)

    袁红; 陈舒

    2012-01-01

    This paper firstly introduced the theory of website usability and the Distance of Information-state Transition (DIT) and constructed the website usability model on basis of DIT, then carried on the web usability testing on 14 universities. This study will provide a theoretical reference for enhancing the usability of university portal and the optimization of network information resources.%在阐述网站易用性和信息距离基本理论的基础上,建立基于信息距离的网站易用性测度模型,运用该模型对国内14所高校门户网站进行易用性测度。研究结论或可为提升高校门户网站的易用性及网络信息资源的优化提供理论参考。

  3. The DDO IVC Distance Project

    CERN Document Server

    Gladders, M D; Burns, C R; Attard, A; Casey, M P; Hamilton, D; Mallén-Ornelas, G; Karr, J L; Poirier, S M; Sawicki, M; Barrientos, F; Barkhouse, W A; Brodwin, M; Clark, J; McNaughton, R; Ruetalo-Pacheco, M; Mochnacki, S W; Gladders, Michael D.; Clarke, Tracy E.; Burns, Christopher R.; Attard, Allen; Casey, Michael P.; Hamilton, Devon; Mallen-Ornelas, Gabriela; Karr, Jennifer L.; Poirier, Sara M.; Sawicki, Marcin; Barrientos, Felipe; Barkhouse, Wayne; Brodwin, Mark; Clark, Jason; Naughton, Rosemary Mc; Ruetalo-Pacheco, Marcelo; Mochnacki, Stefan W.

    1998-01-01

    We present the first set of distance limits from the David Dunlap Observatory Intermediate Velocity Cloud (DDO IVC) distance project. Such distance measures are crucial to understanding the origins and dynamics of IVCs, as the distances set most of the basic physical parameters for the clouds. Currently there are very few IVCs with reliably known distances. This paper describes in some detail the basic techniques used to measure distances, with particular emphasis on the the analysis of interstellar absorption line data, which forms the basis of our distance determinations. As an example, we provide a detailed description of our distance determination for the Draco Cloud. Preliminary distance limits for a total of eleven clouds are provided.

  4. Advanced hierarchical distance sampling

    Science.gov (United States)

    Royle, Andy

    2016-01-01

    In this chapter, we cover a number of important extensions of the basic hierarchical distance-sampling (HDS) framework from Chapter 8. First, we discuss the inclusion of “individual covariates,” such as group size, in the HDS model. This is important in many surveys where animals form natural groups that are the primary observation unit, with the size of the group expected to have some influence on detectability. We also discuss HDS integrated with time-removal and double-observer or capture-recapture sampling. These “combined protocols” can be formulated as HDS models with individual covariates, and thus they have a commonality with HDS models involving group structure (group size being just another individual covariate). We cover several varieties of open-population HDS models that accommodate population dynamics. On one end of the spectrum, we cover models that allow replicate distance sampling surveys within a year, which estimate abundance relative to availability and temporary emigration through time. We consider a robust design version of that model. We then consider models with explicit dynamics based on the Dail and Madsen (2011) model and the work of Sollmann et al. (2015). The final major theme of this chapter is relatively newly developed spatial distance sampling models that accommodate explicit models describing the spatial distribution of individuals known as Point Process models. We provide novel formulations of spatial DS and HDS models in this chapter, including implementations of those models in the unmarked package using a hack of the pcount function for N-mixture models.

  5. Distance Metric Tracking

    Science.gov (United States)

    2016-03-02

    520, 2004. 16 [12] E.C. Hall and R.M. Willett. Online convex optimization in dynamic environ- ments. Selected Topics in Signal Processing, IEEE Journal...Conference on Machine Learning, pages 1160–1167. ACM, 2008. [25] Eric P Xing, Michael I Jordan, Stuart Russell, and Andrew Y Ng. Distance metric...whereBψ is any Bregman divergence and ηt is the learning rate parameter. From ( Hall & Willett, 2015) we have: Theorem 1. G` = max θ∈Θ,`∈L ‖∇f(θ)‖ φmax = 1

  6. Long distance tunneling

    CERN Document Server

    Ivlev, B I

    2005-01-01

    Quantum tunneling between two potential wells in a magnetic field can be strongly increased when the potential barrier varies in the direction perpendicular to the line connecting the two wells and remains constant along this line. A periodic structure of the wave function is formed in the direction joining the wells. The resulting motion can be coherent like motion in a conventional narrow band periodic structure. A particle penetrates the barrier over a long distance which strongly contrasts to WKB-like tunneling. The whole problem is stationary. The coherent process can be influenced by dissipation.

  7. Distances on Lozenge Tilings

    CERN Document Server

    Bodini, Olivier; Fernique, Thomas

    2009-01-01

    In this paper, a structural property of the set of lozenge tilings of a 2n-gon is highlighted. We introduce a simple combinatorial value called Hamming-distance, which is a lower bound for the flipdistance (i.e. the number of necessary local transformations involving three lozenges) between two given tilings. It is here proven that, for n5, We show that there is some deficient pairs of tilings for which the flip connection needs more flips than the combinatorial lower bound indicates.

  8. Distance Teaching on Bornholm

    DEFF Research Database (Denmark)

    Hansen, Finn J. S.; Clausen, Christian

    2001-01-01

    and the organisational set-up. It is debated which kind of social learning that has taken place. The innovation process was based on the implementation of an inflexible video-conference system without any proactive considerations of organisational change or pedagocical development. User appropriation of the technology......The case study represents an example of a top-down introduction of distance teaching as part of Danish trials with the introduction of multimedia in education. The study is concerned with the background, aim and context of the trial as well as the role and working of the technology...

  9. A Behavioral Distance for Fuzzy-Transition Systems

    CERN Document Server

    Cao, Yongzhi; Sun, Sherry X; Chen, Guoqing

    2011-01-01

    In contrast to the existing approaches to bisimulation for fuzzy systems, we introduce a behavioral distance to measure the behavioral similarity of states in a nondeterministic fuzzy-transition system. This behavioral distance is defined as the greatest fixed point of a suitable monotonic function and provides a quantitative analogue of bisimilarity. The behavioral distance has the important property that two states are at zero distance if and only if they are bisimilar. Moreover, for any given threshold, we find that states with behavioral distances bounded by the threshold are equivalent. In addition, we show that two system combinators---parallel composition and product---are non-expansive with respect to our behavioral distance, which makes compositional verification possible.

  10. Distance Learning. Volume I: Distance Learning Analysis Study.

    Science.gov (United States)

    1998-09-01

    The primary focus of this project is the determination of the feasibility and cost effectiveness of applying Distance Learning strategies to 22...selected PPSCP courses and development of a Distance Learning Analysis Procedures Manual.

  11. PERBANDINGAN EUCLIDEAN DISTANCE DENGAN CANBERRA DISTANCE PADA FACE RECOGNITION

    Directory of Open Access Journals (Sweden)

    Sendhy Rachmat Wurdianarto

    2014-08-01

    Full Text Available Perkembangan ilmu pada dunia komputer sangatlah pesat. Salah satu yang menandai hal ini adalah ilmu komputer telah merambah pada dunia biometrik. Arti biometrik sendiri adalah karakter-karakter manusia yang dapat digunakan untuk membedakan antara orang yang satu dengan yang lainnya. Salah satu pemanfaatan karakter / organ tubuh pada setiap manusia yang digunakan untuk identifikasi (pengenalan adalah dengan memanfaatkan wajah. Dari permasalahan diatas dalam pengenalan lebih tentang aplikasi Matlab pada Face Recognation menggunakan metode Euclidean Distance dan Canberra Distance. Model pengembangan aplikasi yang digunakan adalah model waterfall. Model waterfall beriisi rangkaian aktivitas proses yang disajikan dalam proses analisa kebutuhan, desain menggunakan UML (Unified Modeling Language, inputan objek gambar diproses menggunakan Euclidean Distance dan Canberra Distance. Kesimpulan yang dapat ditarik adalah aplikasi face Recognation menggunakan metode euclidean Distance dan Canverra Distance terdapat kelebihan dan kekurangan masing-masing. Untuk kedepannya aplikasi tersebut dapat dikembangkan dengan menggunakan objek berupa video ataupun objek lainnya.   Kata kunci : Euclidean Distance, Face Recognition, Biometrik, Canberra Distance

  12. Time delay and distance measurement

    Science.gov (United States)

    Abshire, James B. (Inventor); Sun, Xiaoli (Inventor)

    2011-01-01

    A method for measuring time delay and distance may include providing an electromagnetic radiation carrier frequency and modulating one or more of amplitude, phase, frequency, polarization, and pointing angle of the carrier frequency with a return to zero (RZ) pseudo random noise (PN) code. The RZ PN code may have a constant bit period and a pulse duration that is less than the bit period. A receiver may detect the electromagnetic radiation and calculate the scattering profile versus time (or range) by computing a cross correlation function between the recorded received signal and a three-state RZ PN code kernel in the receiver. The method also may be used for pulse delay time (i.e., PPM) communications.

  13. Minimal distances between SCFTs

    Energy Technology Data Exchange (ETDEWEB)

    Buican, Matthew [Department of Physics and Astronomy, Rutgers University,Piscataway, NJ 08854 (United States)

    2014-01-28

    We study lower bounds on the minimal distance in theory space between four-dimensional superconformal field theories (SCFTs) connected via broad classes of renormalization group (RG) flows preserving various amounts of supersymmetry (SUSY). For N=1 RG flows, the ultraviolet (UV) and infrared (IR) endpoints of the flow can be parametrically close. On the other hand, for RG flows emanating from a maximally supersymmetric SCFT, the distance to the IR theory cannot be arbitrarily small regardless of the amount of (non-trivial) SUSY preserved along the flow. The case of RG flows from N=2 UV SCFTs is more subtle. We argue that for RG flows preserving the full N=2 SUSY, there are various obstructions to finding examples with parametrically close UV and IR endpoints. Under reasonable assumptions, these obstructions include: unitarity, known bounds on the c central charge derived from associativity of the operator product expansion, and the central charge bounds of Hofman and Maldacena. On the other hand, for RG flows that break N=2→N=1, it is possible to find IR fixed points that are parametrically close to the UV ones. In this case, we argue that if the UV SCFT possesses a single stress tensor, then such RG flows excite of order all the degrees of freedom of the UV theory. Furthermore, if the UV theory has some flavor symmetry, we argue that the UV central charges should not be too large relative to certain parameters in the theory.

  14. On distance variation effects on graphene bilayers

    Science.gov (United States)

    Naji, S.; Bhihi, M.; Labrim, H.; Belhaj, A.; Benyoussef, A.; El Kenz, A.; Loulidi, M.

    2014-06-01

    The opening of the energy gap and the total energy of the graphene-like bilayers are investigated using ab initio calculations. The studied model consists of a static single layer of graphene interacting with an extra dynamic one placed at a varying vertical distance d in the (AB) stacking arrangement. The effects of the vertical distance variation on the energy gap and the total energy of the system are discussed first. Starting from a distance around the van der Waals length, the energy gap does not depend on the vertical distance variation and the system exhibits graphene-like properties with minor deformations in the lattice size parameter and the energy dispersion behaviour around K points. However, it has been shown that the diagonal distance variation of the graphene-like bilayer modifies the electronic structure properties. This modification depends on an intermediate stacking arrangement between the (AA) and the (AB) configurations. It has been shown that the diagonal distance variation has an influence on the states of pz electrons in the (AB) arrangement and it can be explored to open the energy gap.

  15. The Distance to M51

    CERN Document Server

    McQuinn, Kristen B W; Dolphin, Andrew E; Berg, Danielle; Kennicutt, Robert

    2016-01-01

    Great investments of observing time have been dedicated to the study of nearby spiral galaxies with diverse goals ranging from understanding the star formation process to characterizing their dark matter distributions. Accurate distances are fundamental to interpreting observations of these galaxies, yet many of the best studied nearby galaxies have distances based on methods with relatively large uncertainties. We have started a program to derive accurate distances to these galaxies. Here we measure the distance to M51 - the Whirlpool galaxy - from newly obtained Hubble Space Telescope optical imaging using the tip of the red giant branch method. We measure the distance modulus to be 8.58+/-0.10 Mpc (statistical), corresponding to a distance modulus of 29.67+/-0.02 mag. Our distance is an improvement over previous results as we use a well-calibrated, stable distance indicator, precision photometry in a optimally selected field of view, and a Bayesian Maximum Likelihood technique that reduces measurement unce...

  16. Improved directional-distance filter

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper proposes a new spatial-distance weighting function.By combining the weighting function and the traditional directional-distance filter (DDF) in a novel way,a new vector filter-the adaptive distance-weighted directional-distance filter (ADWDDF)-is presented.The experimental results show that the proposed solution provides better filtering performance and preserves better image chromaticity and edge or detail information compared with the traditional DDF and some other typical vector filters.

  17. Isolation by distance, web service

    OpenAIRE

    Bohonak Andrew J; Jensen Jeffrey L; Kelley Scott T

    2005-01-01

    Abstract Background The population genetic pattern known as "isolation by distance" results from spatially limited gene flow and is a commonly observed phenomenon in natural populations. However, few software programs exist for estimating the degree of isolation by distance among populations, and they tend not to be user-friendly. Results We have created Isolation by Distance Web Service (IBDWS) a user-friendly web interface for determining patterns of isolation by distance. Using this site, ...

  18. Reconsidering Moore's Transactional Distance Theory

    Science.gov (United States)

    Giossos, Yiannis; Koutsouba, Maria; Lionarakis, Antonis; Skavantzos, Kosmas

    2009-01-01

    One of the core theories of distance education is Michael Graham Moore's "Theory of Transactional Distance" that provides the broad framework of the pedagogy of distance education and allows the generation of almost infinite number of hypotheses for research. However, the review of the existing studies relating to the theory showed the use of a…

  19. Contextual Distance Refining for Image Retrieval

    KAUST Repository

    Islam, Almasri

    2014-09-16

    Recently, a number of methods have been proposed to improve image retrieval accuracy by capturing context information. These methods try to compensate for the fact that a visually less similar image might be more relevant because it depicts the same object. We propose a new quick method for refining any pairwise distance metric, it works by iteratively discovering the object in the image from the most similar images, and then refine the distance metric accordingly. Test show that our technique improves over the state of art in terms of accuracy over the MPEG7 dataset.

  20. Preintegration HIV-1 inhibition by a combination lentiviral vector containing a chimeric TRIM5 alpha protein, a CCR5 shRNA, and a TAR decoy.

    Science.gov (United States)

    Anderson, Joseph S; Javien, John; Nolta, Jan A; Bauer, Gerhard

    2009-12-01

    Human immunodeficiency virus (HIV) gene therapy offers a promising alternative approach to current antiretroviral treatments to inhibit HIV-1 infection. Various stages of the HIV life cycle including pre-entry, preintegration, and postintegration can be targeted by gene therapy to block viral infection and replication. By combining multiple highly potent anti-HIV transgenes in a single gene therapy vector, HIV-1 resistance can be achieved in transduced cells while prohibiting the generation of escape mutants. Here, we describe a combination lentiviral vector that encodes three highly effective anti-HIV genes functioning at separate stages of the viral life cycle including a CCR5 short hairpin RNA (shRNA) (pre-entry), a human/rhesus macaque chimeric TRIM5 alpha (postentry/preintegration), and a transactivation response element (TAR) decoy (postintegration). The major focus on designing this anti-HIV vector was to block productive infection of HIV-1 and to inhibit any formation of provirus that would maintain the viral reservoir. Upon viral challenge, potent preintegration inhibition of HIV-1 infection was achieved in combination vector-transduced cells in both cultured and primary CD34(+) hematopoietic progenitor cell (HPC)-derived macrophages. The generation of escape mutants was also blocked as evaluated by long-term culture of challenged cells. The ability of this combination anti-HIV lentiviral vector to prevent HIV-1 infection, in vitro, warrants further evaluation of its in vivo efficacy.

  1. PEI-engineered respirable particles delivering a decoy oligonucleotide to NF-κB: inhibiting MUC2 expression in LPS-stimulated airway epithelial cells.

    Directory of Open Access Journals (Sweden)

    Francesca Ungaro

    Full Text Available A specific and promising approach to limit inflammation and mucin iperproduction in chronic lung diseases relies on specific inhibition of nuclear Factor-κB (NF-κB by a decoy oligonucleotide (dec-ODN. To fulfill the requirements dictated by translation of dec-ODN therapy in humans, inhalable dry powders were designed on a rational basis to provide drug protection, sustained release and to optimize pharmacological response. To this end, large porous particles (LPP for dec-ODN delivery made of a sustained release biomaterial (poly(lactic-co-glycolic acid, PLGA and an "adjuvant" hydrophilic polymer (polyethylenimine, PEI were developed and their effects on LPS-stimulated human airway epithelial cells evaluated. The composite PLGA/PEI particles containing dec-ODN (i.e., LPP(PEI were successfully engineered for widespread deposition in the lung and prolonged release of intact dec-ODN in vitro. LPP(PEI caused a prolonged inhibition of IL-8 and MUC2 expression in CF human bronchial epithelial cells and human epithelial pulmonary NCI-H292 cells, respectively, as compared to naked dec-ODN. Nonetheless, as compared to previously developed LPP, the presence of PEI was essential to construct a dec-ODN delivery system able to act in mucoepidermoid lung epithelial cells. In perspective, engineering LPP with PEI may become a key factor for tuning carrier properties, controlling lung inflammation and mucin production which, in turn, can foster in vivo translation of dec-ODN therapy.

  2. Decoy Receptor DcR1 Is Induced in a p50/Bcl3-Dependent Manner and Attenuates the Efficacy of Temozolomide.

    Science.gov (United States)

    Mansour, Nassir M; Bernal, Giovanna M; Wu, Longtao; Crawley, Clayton D; Cahill, Kirk E; Voce, David J; Balyasnikova, Irina V; Zhang, Wei; Spretz, Ruben; Nunez, Luis; Larsen, Gustavo F; Weichselbaum, Ralph R; Yamini, Bakhtiar

    2015-05-15

    Temozolomide is used widely to treat malignant glioma, but the overall response to this agent is generally poor. Resistance to DNA-damaging drugs such as temozolomide has been related to the induction of antiapoptotic proteins. Specifically, the transcription factor NF-κB has been suggested to participate in promoting the survival of cells exposed to chemotherapy. To identify factors that modulate cytotoxicity in the setting of DNA damage, we used an unbiased strategy to examine the NF-κB-dependent expression profile induced by temozolomide. By this route, we defined the decoy receptor DcR1 as a temozolomide response gene induced by a mechanism relying upon p50/NF-κB1. A conserved NF-κB-binding sequence (κB-site) was identified in the proximal promoter and was demonstrated to be required for DcR1 induction by temozolomide. Loss-of-function and gain-of-function studies reveal that the atypical IκB protein, Bcl3, is also required for induction of DcR1 by temozolomide. Mechanistically, DcR1 attenuates temozolomide efficacy by blunting activation of the Fas receptor pathway in p53(+/+) glioma cells. Intracranial xenograft studies show that DcR1 depletion in glioma cells enhances the efficacy of temozolomide. Taken together, our results show how DcR1 upregulation mediates temozolomide resistance and provide a rationale for DcR1 targeting as a strategy to sensitize gliomas to this widely used chemotherapy.

  3. The Antiangiogenic Effects of a Vascular Endothelial Growth Factor Decoy Receptor Can Be Monitored in Vivo Using Contrast-Enhanced Ultrasound Imaging

    Directory of Open Access Journals (Sweden)

    Flemming Forsberg

    2014-03-01

    Full Text Available The development of antiangiogenic therapies has stimulated interest in noninvasive imaging methods to monitor response. We investigated whether the effects of a vascular endothelial growth factor decoy receptor (VEGF Trap, Regeneron Pharmaceuticals, Tarrytown, NY could be monitored in vivo using contrast-enhanced ultrasonography (CEUS. Twenty nude mice (in two groups were implanted with a human melanoma cell line (DB-1. The active group received VEGF Trap (4 × 25 mg/kg over 2 weeks, whereas the control group received an inactive protein. An ultrasound contrast agent was injected followed by power Doppler imaging (PDI and pulse inversion harmonic imaging (PIHI; regular and intermittent. Specimens were sectioned in the same planes as the images and stained for endothelial cells (CD31, cyclooxygenase-2 (COX-2, VEGF, and hypoxia (Glut1. Measures of tumor vascularity obtained with the different imaging modes were compared to immunohistochemical markers of angiogenesis. Mean tumor volume was smaller in the active group than in the control group (656 ± 225 vs 1,160 ± 605 mm3. Overall, PDI and VEGF correlated (r = .34; p = .037. Vascularity decreased from control to treated mice with intermittent PIHI, as did the expression of CD31 and COX-2 (p # .02, whereas VEGF increased (p = .05. CEUS appears to allow in vivo monitoring of the antiangiogenic effects of VEGF Trap in the DB-1 human melanoma xenograft model.

  4. Keeping Your Distance is Hard

    OpenAIRE

    Burke, Kyle; Heubach, Silvia; Huggan, Melissa; Huntemann, Svenja

    2016-01-01

    We study the computational complexity of distance games, a class of combinatorial games played on graphs. A move consists of colouring an uncoloured vertex subject to it not being at certain distances determined by two sets, D and S. D is the set of forbidden distances for colouring vertices in different colors, while S is the set of forbidden distances for the same colour. The last player to move wins. Well-known examples of distance games are Node-Kayles, Snort, and Col, whose complexities ...

  5. Distance learning and perioperative nursing.

    Science.gov (United States)

    Gruendemann, Barbara J

    2007-03-01

    Distance learning in nursing education is arriving with unprecedented speed, which has led to much uncertainty among educators. This article provides an overview of distance learning and its application to perioperative nursing. Lack of face-to-face interaction is of foremost concern in distance learning, and educators must develop new teaching strategies to address this problem. Models for assessing outcomes and effectiveness are important tools to use when implementing a distance learning program. Basic perioperative nursing concepts, skills, procedures, and recommended practices can be introduced effectively with online distance learning modalities and then reinforced through a clinical component.

  6. New distances to RAVE stars

    CERN Document Server

    Binney, James; Kordopatis, Georges; McMillan, Paul J; Sharma, Sanjib; Zwitter, Tomaz; Bienayme, Olivier; Bland-Hawthorn, Joss; Steinmetz, Matthias; Gilmore, Gerry; Williams, Mary E K; Navarro, Julio; Grebel, Eva K; Helmi, Amina; Parker, Quentin; Reid, Warren A; Seabroke, George; Watson, Fred; Wyse, Rosie F G

    2013-01-01

    Probability density functions are determined from new stellar parameters for the distance moduli of stars for which the RAdial Velocity Experiment (RAVE) has obtained spectra with S/N>=10. The expectation value of distance is larger than the distance implied by the expectation of distance modulus; the latter is itself larger than the distance implied by the expectation value of the parallax. Our parallaxes of Hipparcos stars agree well with the values measured by Hipparcos, so the expectation of parallax is the most reliable distance indicator. The latter are improved by taking extinction into account. We provide one- two- or three-Gaussian fits to the distance pdfs. The effective temperature absolute-magnitude diagram of our stars is significantly improved when these pdfs are used to make the diagram. We use the method of kinematic corrections devised by Schoenrich, Binney & Asplund to check for systematic errors in our estimators for ordinary stars and confirm the conclusion reached from the Hipparcos s...

  7. Length and distance on a quantum space

    CERN Document Server

    Martinetti, Pierre

    2012-01-01

    This contribution is an introduction to the metric aspect of noncommutative geometry, with emphasize on the Moyal plane. Starting by questioning "how to define a standard meter in a space whose coordinates no longer commute?", we list several recent results regarding Connes's spectral distance calculated between eigenstates of the quantum harmonic oscillator arXiv:0912.0906, as well as between coherent states arXiv:1110.6164. We also question the difference (which remains hidden in the commutative case) between the spectral distance and the notion of quantum length inherited from the length operator defined in various models of noncommutative space-time (DFR and \\theta-Minkowski). We recall that a standard procedure in noncommutative geometry, consisting in doubling the spectral triple, allows to fruitfully confront the spectral distance with the quantum length. Finally we refine the idea of discrete vs. continuous geodesics in the Moyal plane, introduced in arXiv:1106.0261.

  8. The social distance theory of power.

    Science.gov (United States)

    Magee, Joe C; Smith, Pamela K

    2013-05-01

    We propose that asymmetric dependence between individuals (i.e., power) produces asymmetric social distance, with high-power individuals feeling more distant than low-power individuals. From this insight, we articulate predictions about how power affects (a) social comparison, (b) susceptibility to influence, (c) mental state inference and responsiveness, and (d) emotions. We then explain how high-power individuals' greater experienced social distance leads them to engage in more abstract mental representation. This mediating process of construal level generates predictions about how power affects (a) goal selection and pursuit, (b) attention to desirability and feasibility concerns, (c) subjective certainty, (d) value-behavior correspondence, (e) self-control, and (f) person perception. We also reassess the approach/inhibition theory of power, noting limitations both in what it can predict and in the evidence directly supporting its proposed mechanisms. Finally, we discuss moderators and methodological recommendations for the study of power from a social distance perspective.

  9. Fast computation of distance estimators

    Directory of Open Access Journals (Sweden)

    Lagergren Jens

    2007-03-01

    Full Text Available Abstract Background Some distance methods are among the most commonly used methods for reconstructing phylogenetic trees from sequence data. The input to a distance method is a distance matrix, containing estimated pairwise distances between all pairs of taxa. Distance methods themselves are often fast, e.g., the famous and popular Neighbor Joining (NJ algorithm reconstructs a phylogeny of n taxa in time O(n3. Unfortunately, the fastest practical algorithms known for Computing the distance matrix, from n sequences of length l, takes time proportional to l·n2. Since the sequence length typically is much larger than the number of taxa, the distance estimation is the bottleneck in phylogeny reconstruction. This bottleneck is especially apparent in reconstruction of large phylogenies or in applications where many trees have to be reconstructed, e.g., bootstrapping and genome wide applications. Results We give an advanced algorithm for Computing the number of mutational events between DNA sequences which is significantly faster than both Phylip and Paup. Moreover, we give a new method for estimating pairwise distances between sequences which contain ambiguity Symbols. This new method is shown to be more accurate as well as faster than earlier methods. Conclusion Our novel algorithm for Computing distance estimators provides a valuable tool in phylogeny reconstruction. Since the running time of our distance estimation algorithm is comparable to that of most distance methods, the previous bottleneck is removed. All distance methods, such as NJ, require a distance matrix as input and, hence, our novel algorithm significantly improves the overall running time of all distance methods. In particular, we show for real world biological applications how the running time of phylogeny reconstruction using NJ is improved from a matter of hours to a matter of seconds.

  10. Trends and Issues in Distance Education: International Perspectives

    OpenAIRE

    2006-01-01

    Trends and Issues in Distance Education: International Perspectives Edited by Yusra Laila Visser, Lya Visser, Michael Simonsın, & Ray Amirault, 2005, United States of America: Information Age Publishing, Inc. pp. 315. ISBN 1-59311-212-2 Reviewed by Dr. Erhan EROGLU Anadolu University Eskisehir, TURKEY In this book, the terms of “distance education” has been discussed from different perspectives. The term “distance education” conjures up in many minds the image of modern, computer-enabled t...

  11. Planning with Reachable Distances

    KAUST Repository

    Tang, Xinyu

    2009-01-01

    Motion planning for spatially constrained robots is difficult due to additional constraints placed on the robot, such as closure constraints for closed chains or requirements on end effector placement for articulated linkages. It is usually computationally too expensive to apply sampling-based planners to these problems since it is difficult to generate valid configurations. We overcome this challenge by redefining the robot\\'s degrees of freedom and constraints into a new set of parameters, called reachable distance space (RD-space), in which all configurations lie in the set of constraint-satisfying subspaces. This enables us to directly sample the constrained subspaces with complexity linear in the robot\\'s number of degrees of freedom. In addition to supporting efficient sampling, we show that the RD-space formulation naturally supports planning, and in particular, we design a local planner suitable for use by sampling-based planners. We demonstrate the effectiveness and efficiency of our approach for several systems including closed chain planning with multiple loops, restricted end effector sampling, and on-line planning for drawing/sculpting. We can sample single-loop closed chain systems with 1000 links in time comparable to open chain sampling, and we can generate samples for 1000-link multi-loop systems of varying topology in less than a second. © 2009 Springer-Verlag.

  12. Trends and Issues in Distance Education: International Perspectives

    Directory of Open Access Journals (Sweden)

    Erhan EROGLU

    2006-04-01

    Full Text Available Trends and Issues in Distance Education: International Perspectives Edited by Yusra Laila Visser, Lya Visser, Michael Simonsın, & Ray Amirault, 2005, United States of America: Information Age Publishing, Inc. pp. 315. ISBN 1-59311-212-2 Reviewed by Dr. Erhan EROGLU Anadolu University Eskisehir, TURKEY In this book, the terms of “distance education” has been discussed from different perspectives. The term “distance education” conjures up in many minds the image of modern, computer-enabled technology that has blossomed in only the last twenty years. Many of the lessons learned over the last century of distance education research and practice have been implemented in a wide variety of distance education programs worldwide, from higher education online learning programs in the United States to rural, radio-based instructional programs in developing countries. Distance education is truly international discipline. While it is true that the term “distance education” has a universal definiton, local distance ducation experiences are often quite idiosyncratic. This idiosyncratic nature emerges from the need to integrate distance education within the constraints, oppurtunities, and realities of spesific cultural and geographic contexts. From these local distance education experiences, educators are developing new understandings of the broader field of distance education, including the trends and issues present in the field. ORGANIZATION OF THE SECTIONS This book has been organized by thematic content into four main sections. Each of these sections represents a unique level of analysis for trends and issues in distance education. Part I presents five distinct perspectives on the state of distance education and the trends and issues of the field. First perspective of five distinct perpectives is “a survey of progressive and conservative trends in education with implications for distance education practice.” Second perspective is

  13. Constraining the Correlation Distance in Quantum Measurements

    CERN Document Server

    Schneider, Jean

    2010-01-01

    Standard Quantum Physics states that the outcome of measurements for some distant entangled subsystems are instantaneously statistically correlated, whatever their mutual distance. This correlation presents itself as if there were a correlation at a distance with infinite speed. It is expressed by the Bell Theorem. It has been experimentally verified over distances up to 18 km with a time resolution of a few picosecond, which can be translated into an apparent effective correlation speed larger than 10^7 c. The purpose of the present White Paper is to discuss the scientific interest and the feasibility to extend the correlation distance up to the Earth-Moon distance, i.e. 2 10^4 times larger than in present experiments. We are thus led to propose to install on the Moon a polarimter and a high performance photon detector with a high temporal resolution. Such an exploratory experiment would provide new tests of Quantum Physics and could perhaps discriminate between standard Quantum Physics and for instance the ...

  14. Distance learning for similarity estimation.

    Science.gov (United States)

    Yu, Jie; Amores, Jaume; Sebe, Nicu; Radeva, Petia; Tian, Qi

    2008-03-01

    In this paper, we present a general guideline to find a better distance measure for similarity estimation based on statistical analysis of distribution models and distance functions. A new set of distance measures are derived from the harmonic distance, the geometric distance, and their generalized variants according to the Maximum Likelihood theory. These measures can provide a more accurate feature model than the classical Euclidean and Manhattan distances. We also find that the feature elements are often from heterogeneous sources that may have different influence on similarity estimation. Therefore, the assumption of single isotropic distribution model is often inappropriate. To alleviate this problem, we use a boosted distance measure framework that finds multiple distance measures which fit the distribution of selected feature elements best for accurate similarity estimation. The new distance measures for similarity estimation are tested on two applications: stereo matching and motion tracking in video sequences. The performance of boosted distance measure is further evaluated on several benchmark data sets from the UCI repository and two image retrieval applications. In all the experiments, robust results are obtained based on the proposed methods.

  15. Distance Education and Foreign Languages. NFLC Occasional Paper [Number 9].

    Science.gov (United States)

    Lambert, Richard D.

    Distance education in second languages in the United States has grown in a piecemeal, uncoordinated fashion, and it remains marginal to both distance education more generally and to the bulk of foreign language instruction throughout the country. One handicap, arising from very limited demand in business for foreign language skills, is lack of…

  16. On distances between phylogenetic trees

    Energy Technology Data Exchange (ETDEWEB)

    DasGupta, B. [Rutgers Univ., Camden, NJ (United States); He, X. [SUNY, Buffalo, NY (United States); Jiang, T. [McMaster Univ., Hamilton, Ontario (Canada)] [and others

    1997-06-01

    Different phylogenetic trees for the same group of species are often produced either by procedures that use diverse optimality criteria or from different genes in the study of molecular evolution. Comparing these trees to find their similarities and dissimilarities, i.e. distance, is thus an important issue in computational molecular biology. The nearest neighbor interchange distance and the subtree-transfer distance are two major distance metrics that have been proposed and extensively studied for different reasons. Despite their many appealing aspects such as simplicity and sensitivity to tree topologies, computing these distances has remained very challenging. This article studies the complexity and efficient approximation algorithms for computing the nni distance and a natural extension of the subtree-transfer distance, called the linear-cost subtree-transfer distance. The linear-cost subtree-transfer model is more logical than the subtree-transfer model and in fact coincides with the nni model under certain conditions. The following results have been obtained as part of our project of building a comprehensive software package for computing distances between phylogenies. (1) Computing the nni distance is NP-complete. This solves a 25 year old open question appearing again and again in, for example, under the complexity-theoretic assumption of P {ne} NP. We also answer an open question regarding the nni distance between unlabeled trees for which an erroneous proof appeared in. We give an algorithm to compute the optimal nni sequence in time O(n{sup 2} logn + n {circ} 2{sup O(d)}), where the nni distance is at most d. (2) Biological applications require us to extend the nni and linear-cost subtree-transfer models to weighted phylogenies, where edge weights indicate the length of evolution along each edge. We present a logarithmic ratio approximation algorithm for nni and a ratio 2 approximation algorithm for linear-cost subtree-transfer, on weighted trees.

  17. DISTANCE EDUCATOR: A Multiskill Personality

    Directory of Open Access Journals (Sweden)

    Sangeeta MALIK

    2013-01-01

    Full Text Available When we talk about a distance educator and a conventional educator the difference we found nd about both of them is that, a distance educator needs to play multiple roles as compared to a conventional educator. They require more skills and knowledge cater to the needs of the learner. In this article we will cover all the responsible areas of a distance educator & why we should consider them as a multiskill personality?

  18. Splitting statistical potentials into meaningful scoring functions: Testing the prediction of near-native structures from decoy conformations

    Directory of Open Access Journals (Sweden)

    Oliva Baldo

    2009-11-01

    Full Text Available Abstract Background Recent advances on high-throughput technologies have produced a vast amount of protein sequences, while the number of high-resolution structures has seen a limited increase. This has impelled the production of many strategies to built protein structures from its sequence, generating a considerable amount of alternative models. The selection of the closest model to the native conformation has thus become crucial for structure prediction. Several methods have been developed to score protein models by energies, knowledge-based potentials and combination of both. Results Here, we present and demonstrate a theory to split the knowledge-based potentials in scoring terms biologically meaningful and to combine them in new scores to predict near-native structures. Our strategy allows circumventing the problem of defining the reference state. In this approach we give the proof for a simple and linear application that can be further improved by optimizing the combination of Zscores. Using the simplest composite score ( we obtained predictions similar to state-of-the-art methods. Besides, our approach has the advantage of identifying the most relevant terms involved in the stability of the protein structure. Finally, we also use the composite Zscores to assess the conformation of models and to detect local errors. Conclusion We have introduced a method to split knowledge-based potentials and to solve the problem of defining a reference state. The new scores have detected near-native structures as accurately as state-of-art methods and have been successful to identify wrongly modeled regions of many near-native conformations.

  19. The Extended Edit Distance Metric

    CERN Document Server

    Fuad, Muhammad Marwan Muhammad

    2007-01-01

    Similarity search is an important problem in information retrieval. This similarity is based on a distance. Symbolic representation of time series has attracted many researchers recently, since it reduces the dimensionality of these high dimensional data objects. We propose a new distance metric that is applied to symbolic data objects and we test it on time series data bases in a classification task. We compare it to other distances that are well known in the literature for symbolic data objects. We also prove, mathematically, that our distance is metric.

  20. Transactional Distance and Autonomy in a Distance Learning Environment

    Science.gov (United States)

    Vasiloudis, G.; Koutsouba, M.; Giossos, Y.; Mavroidis, I.

    2015-01-01

    This paper studies the transactional distance between the students and the tutor as well as the autonomy of students in a postgraduate course of the Hellenic Open University (HOU). The aim of the paper is to examine how the relation between autonomy and transactional distance evolves during an academic year and how this relation is affected by…

  1. An Improved Minimum Distance Method Based on Artificial Neural Networks

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    MDM (minimum distance method) is a very popular algorithm in state recognition. But it has a presupposition, that is, the distance within one class must be shorter enough than the distance between classes. When this presupposition is not satisfied, the method is no longer valid. In order to overcome the shortcomings of MDM, an improved mi nimum distance method (IMDM) based on ANN (artificial neural networks) is presented. The simulation results demonstrate that IMDM has two advantages, that is, the rate of recognition is faster and the accuracy of recognition is higher compared with MDM.

  2. Decoy Receptor 3 (DcR3) as a Biomarker of Tumor Deterioration in Female Reproductive Cancers: A Meta-Analysis.

    Science.gov (United States)

    Jiang, Mengtong; Lin, Xiaomiao; He, Rongquan; Lin, Xinggu; Liang, Lu; Tang, Ruixue; Xiong, Dandan; Wei, Kanglai; Dang, Yiwu; Feng, Zhenbo; Chen, Gang

    2016-06-01

    BACKGROUND DcR3 (decoy receptor 3) has been proposed be involved in development and prognosis of female reproductive cancers, including cervical cancer, ovarian cancer, and breast cancer. The purpose of this meta-analysis was to explore the evidence for the correlation between DcR3 and the clinicopathological characteristics, as well as the overall survival time, in female reproductive cancers. MATERIAL AND METHODS Relevant studies were searched for in PubMed, Wiley Online Library, Web of Science, Science Direct, Cochrane Central Register of Controlled Trials, Google Scholar, EMBASE, Ovid, LILACS, Chinese CNKI, Chong Qing VIP, Wan Fang, and China Biology Medicine disc up to 30 September 2015. Data on the relationship between DcR3 expression and TNM stage, differentiation, lymph node metastasis, age, and overall survival time were extracted. Pooled odds ratios (ORs) and 95% CIs (confidence intervals) were estimated by forest plot. RESULTS Twelve studies with 1127 patients met the inclusion criteria for this meta-analysis. Overexpression of DcR3 was significantly related to the risk of female reproductive cancers (OR=10.69, 95% CI: 6.33-18.05), TNM stage (OR=5.51, 95% CI: 2.83-10.71), differentiation (OR=4.16, 95% CI: 2.28-7.60), lymph node metastasis (OR=5.89, 95% CI: 3.16-10.9), age (OR=0.85, 95% CI: 0.51-1.44), and overall survival time (OR=1.84, 95% CI: 0.58-5.83). Subgroup analyses showed that overexpression of DcR3 in cervical, ovarian, and breast cancer all had similar relationships with these clinicopathological parameters. CONCLUSIONS Our meta-analysis suggests that overexpression of DcR3 may play vital roles in the tumorigenesis and deterioration of female reproductive cancers. However, the relationship between DcR3 expression and prognosis needs further investigation.

  3. Deletion of Chromosomal Region 8p21 Confers Resistance to Bortezomib and Is Associated with Upregulated Decoy TRAIL Receptor Expression in Patients with Multiple Myeloma.

    Directory of Open Access Journals (Sweden)

    Adil Doganay Duru

    Full Text Available Loss of the chromosomal region 8p21 negatively effects survival in patients with multiple myeloma (MM that undergo autologous stem cell transplantation (ASCT. In this study, we aimed to identify the immunological and molecular consequences of del(8(p21 with regards to treatment response and bortezomib resistance. In patients receiving bortezomib as a single first line agent without any high-dose therapy, we have observed that patients with del(8(p21 responded poorly to bortezomib with 50% showing no response while patients without the deletion had a response rate of 90%. In vitro analysis revealed a higher resistance to bortezomib possibly due to an altered gene expression profile caused by del(8(p21 including genes such as TRAIL-R4, CCDC25, RHOBTB2, PTK2B, SCARA3, MYC, BCL2 and TP53. Furthermore, while bortezomib sensitized MM cells without del(8(p21 to TRAIL/APO2L mediated apoptosis, in cells with del(8(p21 bortezomib failed to upregulate the pro-apoptotic death receptors TRAIL-R1 and TRAIL-R2 which are located on the 8p21 region. Also expressing higher levels of the decoy death receptor TRAIL-R4, these cells were largely resistant to TRAIL/APO2L mediated apoptosis. Corroborating the clinical outcome of the patients, our data provides a potential explanation regarding the poor response of MM patients with del(8(p21 to bortezomib treatment. Furthermore, our clinical analysis suggests that including immunomodulatory agents such as Lenalidomide in the treatment regimen may help to overcome this negative effect, providing an alternative consideration in treatment planning of MM patients with del(8(p21.

  4. Molecular decoy to the Y-box binding protein-1 suppresses the growth of breast and prostate cancer cells whilst sparing normal cell viability.

    Directory of Open Access Journals (Sweden)

    Jennifer H Law

    Full Text Available The Y-box binding protein-1 (YB-1 is an oncogenic transcription/translation factor that is activated by phosphorylation at S102 whereby it induces the expression of growth promoting genes such as EGFR and HER-2. We recently illustrated by an in vitro kinase assay that a novel peptide to YB-1 was highly phosphorylated by the serine/threonine p90 S6 kinases RSK-1 and RSK-2, and to a lesser degree PKCα and AKT. Herein, we sought to develop this decoy cell permeable peptide (CPP as a cancer therapeutic. This 9-mer was designed as an interference peptide that would prevent endogenous YB-1(S102 phosphorylation based on molecular docking. In cancer cells, the CPP blocked P-YB-1(S102 and down-regulated both HER-2 and EGFR transcript level and protein expression. Further, the CPP prevented YB-1 from binding to the EGFR promoter in a gel shift assay. Notably, the growth of breast (SUM149, MDA-MB-453, AU565 and prostate (PC3, LNCap cancer cells was inhibited by ∼90% with the CPP. Further, treatment with this peptide enhanced sensitivity and overcame resistance to trastuzumab in cells expressing amplified HER-2. By contrast, the CPP had no inhibitory effect on the growth of normal immortalized breast epithelial (184htert cells, primary breast epithelial cells, nor did it inhibit differentiation of hematopoietic progenitors. These data collectively suggest that the CPP is a novel approach to suppressing the growth of cancer cells while sparing normal cells and thereby establishes a proof-of-concept that blocking YB-1 activation is a new course of cancer therapeutics.

  5. Enhancing the secure key rate in a quantum-key-distribution system using discrete-variable, high-dimensional, time-frequency states

    Science.gov (United States)

    Islam, Nurul T.; Cahall, Clinton; Aragoneses, Andrés.; Lim, Charles Ci Wen; Allman, Michael S.; Verma, Varun; Nam, Sae Woo; Kim, Jungsang; Gauthier, Daniel J.

    2016-10-01

    High-dimensional (dimension d > 2) quantum key distribution (QKD) protocols that encode information in the temporal degree of freedom promise to overcome some of the challenges of qubit-based (d = 2) QKD systems. In particular, the long recovery time of single-photon detectors and large channel noise at long distance both limit the rate at which a final secure key can be generated in a low-dimension QKD system. We propose and demonstrate a practical discrete-variable time-frequency protocol with d = 4 at a wavelength of 1550 nm, where the temporal states are secured by transmitting and detecting their dual states under Fourier transformation, known as the frequency-basis states, augmented by a decoy-state protocol. We show that the discrete temporal and frequency states can be generated and detected using commercially-available equipment with high timing and spectral efficiency. In our initial experiments, we only have access to detectors that have low efficiency (1%) at 1550 nm. Together with other component losses, our system is equivalent to a QKD system with ideal components and a 50-km-long optical-fiber quantum channel. We find that our system maintains a spectral visibility of over 99.0% with a quantum bit error rate of 2.3%, which is largely due to the finite extinction ratio of the intensity modulators used in the transmitter. The estimated secure key rate of this system is 7.7×104 KHz, which should improve drastically when we use detectors optimized for 1550 nm.

  6. Virtual Bioinformatics Distance Learning Suite

    Science.gov (United States)

    Tolvanen, Martti; Vihinen, Mauno

    2004-01-01

    Distance learning as a computer-aided concept allows students to take courses from anywhere at any time. In bioinformatics, computers are needed to collect, store, process, and analyze massive amounts of biological and biomedical data. We have applied the concept of distance learning in virtual bioinformatics to provide university course material…

  7. The Psychology of Psychic Distance

    DEFF Research Database (Denmark)

    Håkanson, Lars; Ambos, Björn; Schuster, Anja

    2016-01-01

    and their theoretical underpinnings assume psychic distances to be symmetric. Building on insights from psychology and sociology, this paper demonstrates how national factors and cognitive processes interact in the formation of asymmetric distance perceptions. The results suggest that exposure to other countries...

  8. The Distance to M104

    Science.gov (United States)

    McQuinn, Kristen. B. W.; Skillman, Evan D.; Dolphin, Andrew E.; Berg, Danielle; Kennicutt, Robert

    2016-11-01

    M104 (NGC 4594; the Sombrero galaxy) is a nearby, well-studied elliptical galaxy included in scores of surveys focused on understanding the details of galaxy evolution. Despite the importance of observations of M104, a consensus distance has not yet been established. Here, we use newly obtained Hubble Space Telescope optical imaging to measure the distance to M104 based on the tip of the red giant branch (TRGB) method. Our measurement yields the distance to M104 to be 9.55 ± 0.13 ± 0.31 Mpc equivalent to a distance modulus of 29.90 ± 0.03 ± 0.07 mag. Our distance is an improvement over previous results as we use a well-calibrated, stable distance indicator, precision photometry in a optimally selected field of view, and a Bayesian maximum likelihood technique that reduces measurement uncertainties. The most discrepant previous results are due to Tully-Fisher method distances, which are likely inappropriate for M104 given its peculiar morphology and structure. Our results are part of a larger program to measure accurate distances to a sample of well-known spiral galaxies (including M51, M74, and M63) using the TRGB method. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  9. The Distance to M51

    Science.gov (United States)

    McQuinn, Kristen. B. W.; Skillman, Evan D.; Dolphin, Andrew E.; Berg, Danielle; Kennicutt, Robert

    2016-07-01

    Great investments of observing time have been dedicated to the study of nearby spiral galaxies with diverse goals ranging from understanding the star formation process to characterizing their dark matter distributions. Accurate distances are fundamental to interpreting observations of these galaxies, yet many of the best studied nearby galaxies have distances based on methods with relatively large uncertainties. We have started a program to derive accurate distances to these galaxies. Here we measure the distance to M51—the Whirlpool galaxy—from newly obtained Hubble Space Telescope optical imaging using the tip of the red giant branch method. We measure the distance modulus to be 8.58 ± 0.10 Mpc (statistical), corresponding to a distance modulus of 29.67 ± 0.02 mag. Our distance is an improvement over previous results as we use a well-calibrated, stable distance indicator, precision photometry in a optimally selected field of view, and a Bayesian Maximum Likelihood technique that reduces measurement uncertainties. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  10. Quality Content in Distance Education

    Science.gov (United States)

    Yildiz, Ezgi Pelin; Isman, Aytekin

    2016-01-01

    In parallel with technological advances in today's world of education activities can be conducted without the constraints of time and space. One of the most important of these activities is distance education. The success of the distance education is possible with content quality. The proliferation of e-learning environment has brought a need for…

  11. Virtual Bioinformatics Distance Learning Suite

    Science.gov (United States)

    Tolvanen, Martti; Vihinen, Mauno

    2004-01-01

    Distance learning as a computer-aided concept allows students to take courses from anywhere at any time. In bioinformatics, computers are needed to collect, store, process, and analyze massive amounts of biological and biomedical data. We have applied the concept of distance learning in virtual bioinformatics to provide university course material…

  12. Distance labeling schemes for trees

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Gørtz, Inge Li; Bistrup Halvorsen, Esben;

    2016-01-01

    We consider distance labeling schemes for trees: given a tree with n nodes, label the nodes with binary strings such that, given the labels of any two nodes, one can determine, by looking only at the labels, the distance in the tree between the two nodes. A lower bound by Gavoille et al. [Gavoill...

  13. New distances to RAVE stars

    NARCIS (Netherlands)

    Binney, J.; Burnett, B.; Kordopatis, G.; McMillan, P. J.; Sharma, S.; Zwitter, T.; Bienayme, O.; Bland-Hawthorn, J.; Steinmetz, M.; Gilmore, G.; Williams, M. E. K.; Navarro, J.; Grebel, E. K.; Helmi, A.; Parker, Q.; Reid, W. A.; Seabroke, G.; Watson, F.; Wyse, R. F. G.

    Probability density functions (pdfs) are determined from new stellar parameters for the distance moduli of stars for which the RAdial Velocity Experiment (RAVE) has obtained spectra with S/N >= 10. Single-Gaussian fits to the pdf in distance modulus suffice for roughly half the stars, with most of

  14. Distance labeling schemes for trees

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Gørtz, Inge Li; Bistrup Halvorsen, Esben

    2016-01-01

    variants such as, for example, small distances in trees [Alstrup et al., SODA, 2003]. We improve the known upper and lower bounds of exact distance labeling by showing that 1/4 log2(n) bits are needed and that 1/2 log2(n) bits are sufficient. We also give (1 + ε)-stretch labeling schemes using Theta...

  15. Faculty Attitudes about Distance Education

    Science.gov (United States)

    Smidt, Esther; McDyre, Brian; Bunk, Jennifer; Li, Rui; Gatenby, Tanya

    2014-01-01

    In recent years, there has been a dramatic increase in distance learning in higher education. Given this, it is extremely important to understand faculty attitudes about distance education, not only because they can vary widely, but also because it is the faculty, through their design and implementation of online courses, that will shape the…

  16. Distance-constrained grid colouring

    Directory of Open Access Journals (Sweden)

    Aszalós László

    2016-06-01

    Full Text Available Distance-constrained colouring is a mathematical model of the frequency assignment problem. This colouring can be treated as an optimization problem so we can use the toolbar of the optimization to solve concrete problems. In this paper, we show performance of distance-constrained grid colouring for two methods which are good in map colouring.

  17. Kinetic distance and kinetic maps from molecular dynamics simulation

    CERN Document Server

    Noe, Frank

    2015-01-01

    Characterizing macromolecular kinetics from molecular dynamics (MD) simulations requires a distance metric that can distinguish slowly-interconverting states. Here we build upon diffusion map theory and define a kinetic distance for irreducible Markov processes that quantifies how slowly molecular conformations interconvert. The kinetic distance can be computed given a model that approximates the eigenvalues and eigenvectors (reaction coordinates) of the MD Markov operator. Here we employ the time-lagged independent component analysis (TICA). The TICA components can be scaled to provide a kinetic map in which the Euclidean distance corresponds to the kinetic distance. As a result, the question of how many TICA dimensions should be kept in a dimensionality reduction approach becomes obsolete, and one parameter less needs to be specified in the kinetic model construction. We demonstrate the approach using TICA and Markov state model (MSM) analyses for illustrative models, protein conformation dynamics in bovine...

  18. Hierarchical traits distances explain grassland Fabaceae species’ ecological niches distances

    Directory of Open Access Journals (Sweden)

    Florian eFort

    2015-02-01

    Full Text Available Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e. ecological niches. We measured a wide range of functional traits (root traits, leaf traits and whole plant traits in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species’ ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance.

  19. Distance labeling schemes for trees

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Gørtz, Inge Li; Bistrup Halvorsen, Esben

    2016-01-01

    We consider distance labeling schemes for trees: given a tree with n nodes, label the nodes with binary strings such that, given the labels of any two nodes, one can determine, by looking only at the labels, the distance in the tree between the two nodes. A lower bound by Gavoille et al. [Gavoille...... variants such as, for example, small distances in trees [Alstrup et al., SODA, 2003]. We improve the known upper and lower bounds of exact distance labeling by showing that 1/4 log2(n) bits are needed and that 1/2 log2(n) bits are sufficient. We also give (1 + ε)-stretch labeling schemes using Theta......(log(n)) bits for constant ε> 0. (1 + ε)-stretch labeling schemes with polylogarithmic label size have previously been established for doubling dimension graphs by Talwar [Talwar, STOC, 2004]. In addition, we present matching upper and lower bounds for distance labeling for caterpillars, showing that labels...

  20. A practical two-way system of quantum key distribution with untrusted source

    Institute of Scientific and Technical Information of China (English)

    Chen Ming-Juan; Liu Xiang

    2011-01-01

    The most severe problem of a two-way “plug-and-play” (p & p) quantum key distribution system is that the source can be controlled by the eavesdropper.This kind of source is defined as an “untrusted source”.This paper discusses the effects of the fluctuation of internal transmittance on the final key generation rate and the transmission distance.The security of the standard BB84 protocol,one-decoy state protocol,and weak+vacuum decoy state protocol,with untrusted sources and the fluctuation of internal transmittance are studied.It is shown that the one-decoy state is sensitive to the statistical fluctuation but weak+vacuum decoy state is only slightly affected by the fluctuation.It is also shown that both the maximum secure transmission distance and final key generation rate are reduced when Alice's laboratory transmittance fluctuation is considered.

  1. Efficient Three-Party Quantum Dialogue Protocol Based on the Continuous Variable GHZ States

    Science.gov (United States)

    Yu, Zhen-Bo; Gong, Li-Hua; Zhu, Qi-Biao; Cheng, Shan; Zhou, Nan-Run

    2016-07-01

    Based on the continuous variable GHZ entangled states, an efficient three-party quantum dialogue protocol is devised, where each legitimate communication party could simultaneously deduce the secret information of the other two parties with perfect efficiency. The security is guaranteed by the correlation of the continuous variable GHZ entangled states and the randomly selected decoy states. Furthermore, the three-party quantum dialogue protocol is directly generalized to an N-party quantum dialogue protocol by using the n-tuple continuous variable GHZ entangled states.

  2. Distance Learning For Mobile Internet Users

    Directory of Open Access Journals (Sweden)

    Beran NECAT

    2007-04-01

    Full Text Available This paper provides an overview on the current state of art in the field of Distance learning for mobile users. It mentions a large range of technologies, services and approaches that may be used to bring distance learning to mobile internet users. These technologies are supposed to considerably increase innovative e-learning solutions for the next generation. While this definitely appears to be true, I think what is not so clear are the implications for students, and lecturers etc. In this article I first evaluate distributed e-learning technologies. With some of the most vital topics, focusing on adaptive distributed e-learning for Mobile Internet Users (MIUs. I also provide a brief analysis of Broadband Network Services, Collaborative e-Learning Tools and Distributed Virtual Environments, Internet-Based Adaptive Learning Technologies and Personalised Distance Learning. I continue my discussion on to Internet Development Tools (IDTs for Distance Learning Solutions, Learning Technologies for MIUs, Semantic and Web-Based Services for Enriching Learning Interactivity, and Evaluations of Distributed Learning Technologies (DLTs.

  3. PRS前沿判别法抗三点源诱偏性能研究%Countering Performance of PRS's Pulse Leading-Edge Distinguishing Technique to Three-Source Decoy Radar System

    Institute of Scientific and Technical Information of China (English)

    许端; 董文锋; 齐秀青; 王正国; 王欢

    2013-01-01

    Aiming at the problem that the tradition passive radar seeker ( PRS) can hardly counter multi-source decoy radar system effectively,we proposed a pulse leading-edge distinguishing technique based on time discrimination technique and wavelet analysis .PRS uses fixed strobe gate to sample the pulse leading-edge,and wavelet analysis and feature extraction are made to the signals obtained .After the analysis result verifies that the sample includes only single radiation source,the PRS can measure the sample signal direction and its frequency,track the sample signal,and attack the source target .Taking three-source decoy radar system with triangular deployment as an example,the usability of this technique was simulated and analyzed .It is verified that the PRS can track the early arriving decoy signal in most position of the airspace,which verifies that this technique can effectively counter three-source decoy radar system .%针对采用传统测向方法的被动雷达导引头( PRS)对抗多点源诱偏系统效果不理想的情况,提出了一种基于时域鉴别技术和小波分析的前沿判别法。由PRS使用固定波门对辐射源脉冲前沿进行采样,对所得信号作小波分析和特征提取,当判定采样信号内为单辐射源信号时对其进行测频、测向、跟踪和打击。以正三角形布阵的三点源诱偏系统为例,仿真分析了该方法的可用性,结果表明在大部分空域中,PRS总能跟踪提前到达的诱饵信号,从而验证了该方法能够有效对抗三点源诱偏系统。

  4. The Distance to M104

    CERN Document Server

    McQuinn, Kristen B W; Dolphin, Andrew E; Berg, Danielle; Kennicutt, Robert

    2016-01-01

    M104 (NGC 4594; the Sombrero galaxy) is a nearby, well-studied elliptical galaxy included in scores of surveys focused on understanding the details of galaxy evolution. Despite the importance of observations of M104, a consensus distance has not yet been established. Here, we use newly obtained Hubble Space Telescope optical imaging to measure the distance to M104 based on the tip of the red giant branch method. Our measurement yields the distance to M104 to be 9.55 +/- 0.13 +/- 0.31 Mpc equivalent to a distance modulus of 29.90 +/- 0.03 +/- 0.07 mag. Our distance is an improvement over previous results as we use a well-calibrated, stable distance indicator, precision photometry in a optimally selected field of view, and a Bayesian Maximum Likelihood technique that reduces measurement uncertainties. The most discrepant previous results are due to Tully-Fisher method distances, which are likely inappropriate for M104 given its peculiar morphology and structure. Our results are part of a larger program to measu...

  5. Distance Learning for Special Populations

    Science.gov (United States)

    Bates, Rodger A.

    2012-01-01

    Distance education strategies for remotely deployed, highly mobile, or institutionalized populations are reviewed and critiqued. Specifically, asynchronous, offline responses for special military units, Native Americans on remote reservations, prison populations and other geographically, temporally or technologically isolated niche populations are…

  6. ECONOMICS OF DISTANCE EDUCATION RECONSIDERED

    Directory of Open Access Journals (Sweden)

    Wolfram LAASER

    2008-07-01

    Full Text Available ABSTRACT According to Gartner a certain hype of e-Learning was followed by a downturn but eLearning will continue to be an important factor in learning scenarios. However the economic viability of e-learning projects will be questioned with more scrutiny than in earlier periods. Therefore it seems to be a good opportunity to see what can be learned from past experience in costing distance learning projects and what aspects are added by current attempts to measure economic efficiency. After reviewing early research about costing distance learning some more recent approaches will be discussed, such as eLearning ROI-calculators and the concept of total cost of ownership. Furthermore some microeconomic effects referring to localization of distance learning courses are outlined. Finally several unsolved issues in costing distance education are summarized.

  7. KNOWLEDGE DISTANCE IN INFORMATION SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Yuhua QIAN; Jiye LIANG; Chuangyin DANG; Feng WANG; Wei XU

    2007-01-01

    In this paper, we first introduce the concepts of knowledge closeness and knowledge distance for measuring the sameness and the difference among knowledge in an information system, respectively.The relationship between these two concepts is a strictly mutual complement relation. We then investigate some important properties of knowledge distance and perform experimental analyses on two public data sets, which show the presented measure appears to be well suited to characterize the nature of knowledge in an information system. Finally, we establish the relationship between the knowledge distance and knowledge granulation, which shows that two variants of the knowledge distance can also be used to construct the knowledge granulation. These results will be helpful for studying uncertainty in information systems.

  8. Graph distance for complex networks

    Science.gov (United States)

    Shimada, Yutaka; Hirata, Yoshito; Ikeguchi, Tohru; Aihara, Kazuyuki

    2016-10-01

    Networks are widely used as a tool for describing diverse real complex systems and have been successfully applied to many fields. The distance between networks is one of the most fundamental concepts for properly classifying real networks, detecting temporal changes in network structures, and effectively predicting their temporal evolution. However, this distance has rarely been discussed in the theory of complex networks. Here, we propose a graph distance between networks based on a Laplacian matrix that reflects the structural and dynamical properties of networked dynamical systems. Our results indicate that the Laplacian-based graph distance effectively quantifies the structural difference between complex networks. We further show that our approach successfully elucidates the temporal properties underlying temporal networks observed in the context of face-to-face human interactions.

  9. Are contemporary tourists consuming distance?

    DEFF Research Database (Denmark)

    Larsen, Gunvor Riber

    2012. Background The background for this research, which explores how tourists represent distance and whether or not distance can be said to be consumed by contemporary tourists, is the increasing leisure mobility of people. Travelling for the purpose of visiting friends and relatives is increasing...... of understanding mobility at a conceptual level, and distance matters to people's manifest mobility: how they travel and how far they travel are central elements of their movements. Therefore leisure mobility (indeed all mobility) is the activity of relating across distance, either through actual corporeal...... that is an inherent part of manifest mobility. Numerous definitions and conceptualisations of tourism have been discussed over the years, with MacCannell (1976) pioneering studies of tourism and leisure travel through to Lash and Urry's (1994) post tourist and Jansson's (2002) hyper-tourist. These definitions...

  10. Academy Distance Learning Tools (IRIS)

    Data.gov (United States)

    Department of Transportation — IRIS is a suite of front-end web applications utilizing a centralized back-end Oracle database. The system fully supports the FAA Academy's Distance Learning Program...

  11. Distances and similarities in intuitionistic fuzzy sets

    CERN Document Server

    Szmidt, Eulalia

    2014-01-01

    This book presents the state-of-the-art in theory and practice regarding similarity and distance measures for intuitionistic fuzzy sets. Quantifying similarity and distances is crucial for many applications, e.g. data mining, machine learning, decision making, and control. The work provides readers with a comprehensive set of theoretical concepts and practical tools for both defining and determining similarity between intuitionistic fuzzy sets. It describes an automatic algorithm for deriving intuitionistic fuzzy sets from data, which can aid in the analysis of information in large databases. The book also discusses other important applications, e.g. the use of similarity measures to evaluate the extent of agreement between experts in the context of decision making.

  12. Categorical perception of tactile distance

    OpenAIRE

    Knight, F. L. C.; Longo, M. R.; Bremner, A.J.

    2014-01-01

    The tactile surface forms a continuous sheet covering the body. And yet, the perceived distance between two touches varies across stimulation sites. Perceived tactile distance is larger when stimuli cross over the wrist, compared to when both fall on either the hand or the forearm. This effect could reflect a categorical distortion of tactile space across body-part boundaries (in which stimuli crossing the wrist boundary are perceptually elongated) or may simply reflect a localised increased ...

  13. Categorical perception of tactile distance.

    Science.gov (United States)

    Knight, Frances Le Cornu; Longo, Matthew R; Bremner, Andrew J

    2014-05-01

    The tactile surface forms a continuous sheet covering the body. And yet, the perceived distance between two touches varies across stimulation sites. Perceived tactile distance is larger when stimuli cross over the wrist, compared to when both fall on either the hand or the forearm. This effect could reflect a categorical distortion of tactile space across body-part boundaries (in which stimuli crossing the wrist boundary are perceptually elongated) or may simply reflect a localised increased in acuity surrounding anatomical landmarks (in which stimuli near the wrist are perceptually elongated). We tested these two interpretations across two experiments, by comparing a well-documented bias to perceive mediolateral tactile distances across the forearm/hand as larger than proximodistal ones along the forearm/hand at three different sites (hand, wrist, and forearm). According to the 'categorical' interpretation, tactile distances should be elongated selectively in the proximodistal axis thus reducing the anisotropy. According to the 'localised acuity' interpretation, distances will be perceptually elongated in the vicinity of the wrist regardless of orientation, leading to increased overall size without affecting anisotropy. Consistent with the categorical account, we found a reduction in the magnitude of anisotropy at the wrist, with no evidence of a corresponding localised increase in precision. These findings demonstrate that we reference touch to a representation of the body that is categorically segmented into discrete parts, which consequently influences the perception of tactile distance.

  14. A STAT3-inhibitory hairpin decoy oligodeoxynucleotide discriminates between STAT1 and STAT3 and induces death in a human colon carcinoma cell line

    Directory of Open Access Journals (Sweden)

    Souissi Inès

    2012-03-01

    Full Text Available Abstract Background The Signal Transducer and Activator of Transcription 3 (STAT3 is activated in tumor cells, and STAT3-inhibitors are able to induce the death of those cells. Decoy oligodeoxynucleotides (dODNs, which bind to the DNA Binding Domain (DBD of STAT3, are efficient inhibitors. However, they also inhibit STAT1, whose activity is essential not only to resistance to pathogens, but also to cell growth inhibition and programmed cell death processes. The aim of this study was to design STAT3-specific dODNs which do not affect STAT1-mediated processes. Results New dODNs with a hairpin (hpdODNs were designed. Modifications were introduced, based on the comparison of STAT3- and STAT1-DBD interactions with DNA using 3D structural analyses. The designed hpdODNs were tested for their ability to inhibit STAT3 but not STAT1 by determining: i cell death in the active STAT3-dependent SW480 colon carcinoma cell line, ii absence of inhibition of interferon (IFN γ-dependent cell death, iii expression of STAT1 targets, and iv nuclear location of STAT3 and STAT1. One hpdODN was found to efficiently induce the death of SW480 cells without interfering with IFNγ-activated STAT1. This hpdODN was found in a complex with STAT3 but not with STAT1 using an original in-cell pull-down assay; this hpdODN also did not inhibit IFNγ-induced STAT1 phosphorylation, nor did it inhibit the expression of the STAT1-target IRF1. Furthermore, it prevented the nuclear transfer of STAT3 but not that of IFNγ-activated STAT1. Conclusions Comparative analyses at the atomic level revealed slight differences in STAT3 and STAT1 DBDs' interaction with their DNA target. These were sufficient to design a new discriminating hpdODN that inhibits STAT3 and not STAT1, thereby inducing tumor cell death without interfering with STAT1-dependent processes. Preferential interaction with STAT3 depends on oligodeoxynucleotide sequence modifications but might also result from DNA shape changes

  15. Decoy Receptor 3 (DcR3) as a Biomarker of Tumor Deterioration in Female Reproductive Cancers: A Meta-Analysis

    Science.gov (United States)

    Jiang, Mengtong; Lin, Xiaomiao; He, Rongquan; Lin, Xinggu; Liang, Lu; Tang, Ruixue; Xiong, Dandan; Wei, Kanglai; Dang, Yiwu; Feng, Zhenbo; Chen, Gang

    2016-01-01

    Background DcR3 (decoy receptor 3) has been proposed be involved in development and prognosis of female reproductive cancers, including cervical cancer, ovarian cancer, and breast cancer. The purpose of this meta-analysis was to explore the evidence for the correlation between DcR3 and the clinicopathological characteristics, as well as the overall survival time, in female reproductive cancers. Material/Methods Relevant studies were searched for in PubMed, Wiley Online Library, Web of Science, Science Direct, Cochrane Central Register of Controlled Trials, Google Scholar, EMBASE, Ovid, LILACS, Chinese CNKI, Chong Qing VIP, Wan Fang, and China Biology Medicine disc up to 30 September 2015. Data on the relationship between DcR3 expression and TNM stage, differentiation, lymph node metastasis, age, and overall survival time were extracted. Pooled odds ratios (ORs) and 95% CIs (confidence intervals) were estimated by forest plot. Results Twelve studies with 1127 patients met the inclusion criteria for this meta-analysis. Overexpression of DcR3 was significantly related to the risk of female reproductive cancers (OR=10.69, 95% CI: 6.33–18.05), TNM stage (OR=5.51, 95% CI: 2.83–10.71), differentiation (OR=4.16, 95% CI: 2.28–7.60), lymph node metastasis (OR=5.89, 95% CI: 3.16–10.9), age (OR=0.85, 95% CI: 0.51–1.44), and overall survival time (OR=1.84, 95% CI: 0.58–5.83). Subgroup analyses showed that overexpression of DcR3 in cervical, ovarian, and breast cancer all had similar relationships with these clinicopathological parameters. Conclusions Our meta-analysis suggests that overexpression of DcR3 may play vital roles in the tumorigenesis and deterioration of female reproductive cancers. However, the relationship between DcR3 expression and prognosis needs further investigation. PMID:27246752

  16. Secure Quantum Key Distribution Network with Bell States and Local Unitary Operations

    Institute of Scientific and Technical Information of China (English)

    LI Chun-Yan; ZHOU Hong-Yu; WANG Yan; DENG Fu-Guo

    2005-01-01

    @@ We propose a theoretical scheme for secure quantum key distribution network following the ideas in quantum dense coding. In this scheme, the server of the network provides the service for preparing and measuring the Bell states,and the users encode the states with local unitary operations. For preventing the server from eavesdropping, we design a decoy when the particle is transmitted between the users. The scheme has high capacity as one particle carries two bits of information and its efficiency for qubits approaches 100%. Moreover, it is unnecessary for the users to store the quantum states, which makes this scheme more convenient in applications than others.

  17. First report of gastrocotylinean post-oncomiracidia (Platyhelminthes: Monogenoidea: Heteronchoinea) on gills of flyingfish (Exocoetidae), snapper (Lutjanidae), dolphinfish (Coryphaenidae), and amberjack (Carangidae) from the Gulf of Mexico: decoy hosts and the dilution effect.

    Science.gov (United States)

    Kritsky, Delane C; Bullard, Stephen A; Bakenhaster, Micah D

    2011-09-01

    Larvae, identified as post-oncomiracidia of the suborder Gastrocotylinea (Monogenoidea), were collected from formalin-fixed gills excised from six species of marine fishes captured from the Gulf of Mexico off Mississippi and Florida: common dolphinfish, Coryphaena hippurus and pompano dolphinfish, Coryphaena equiselis (both Perciformes, Coryphaenidae); gray snapper, Lutjanus griseus (Perciformes, Lutjanidae); greater amberjack, Seriola dumerili (Perciformes, Carangidae); and Atlantic flyingfish, Cheilopogon melanurus and sailfin flyingfish, Parexocoetus hillianus (both Beloniformes and Exocoetidae). Based on a combination of diagnostic morphological features, the specimens were divided into two basic forms, each of which was further subdivided into two morphotypes. No gastrocotylinean post-oncomiracidium had been reported previously from these hosts. Of the six host species, only C. hippurus serves as a host (unconfirmed) for the adult of a gastrocotylinean species, suggesting that the recorded fishes from the Gulf of Mexico comprise dead-end hosts acting as decoys for the oncomiracidia. These comparatively non-susceptible "decoy hosts" apparently dilute the susceptible fish-host population and by intercepting infective larvae (oncomiracidia) decrease the abundance of parasites on their typical hosts.

  18. 用于新型雷达/红外无源复合诱饵的等离子体参数选择%Parameters Choice of Plasma for New Types of Passive Radar and Infrared Compound Decoy

    Institute of Scientific and Technical Information of China (English)

    汪中贤; 韩磊; 史建军; 张正武

    2012-01-01

    根据电磁波在分层介质中阻抗匹配原理,计算了非均匀非磁化等离子体平行与垂直极化波的功率反射系数。基于碱金属盐的高温电离特性,以功率反射系数为研究对象,对雷达无源诱饵用等离子体的厚度、温度和电子密度分布等参数选择进行了分析,并根据所选择的参数讨论了入射角对无源诱饵应用的影响。%According to the impedance matching mechanism when incident microwave transmit in the non-uniform substance,the total wave energy reflectance calculating method of TE wave and TM wave on the surface of plasma was introduced in this paper.The choices of the thickness,temperature and distributing of uncontrolled electron of plasma used for radar passive decoy were studied according to the total wave energy reflectance based on the ionization specialty of the compound alkali metals.And according to the parameters of plasma chosen above,the application impact of radar passive decoy was analyzed under various incidence angle of microwave.

  19. Making Distance Visible: Assembling Nearness in an Online Distance Learning Programme

    Directory of Open Access Journals (Sweden)

    Jen Ross

    2013-09-01

    Full Text Available Online distance learners are in a particularly complex relationship with the educational institutions they belong to (Bayne, Gallagher, & Lamb, 2012. For part-time distance students, arrivals and departures can be multiple and invisible as students take courses, take breaks, move into independent study phases of a programme, find work or family commitments overtaking their study time, experience personal upheaval or loss, and find alignments between their professional and academic work. These comings and goings indicate a fluid and temporary assemblage of engagement, not a permanent or stable state of either “presence” or “distance”. This paper draws from interview data from the “New Geographies of Learning” project, a research project exploring the notions of space and institution for the MSc in Digital Education at the University of Edinburgh, and from literature on distance learning and online community. The concept of nearness emerged from the data analyzing the comings and goings of students on a fully online programme. It proposes that “nearness” to a distance programme is a temporary assemblage of people, circumstances, and technologies. This state is difficult to establish and impossible to sustain in an uninterrupted way over the long period of time that many are engaged in part-time study. Interruptions and subsequent returns should therefore be seen as normal in the practice of studying as an online distance learner, and teachers and institutions should work to help students develop resilience in negotiating various states of nearness. Four strategies for increasing this resilience are proposed: recognising nearness as effortful; identifying affinities; valuing perspective shifts; and designing openings.

  20. Matrimonial distance, inbreeding coefficient and population size: Dhangar data.

    Science.gov (United States)

    Majumder, P P; Malhotra, K C

    1979-01-01

    Data on the distance between the birthplaces of spouses (matrimonial distance) were collected from 2,260 married individuals belonging to 21 endogamous castes of the Dhangar (shepherd) cast-cluster of Maharashtra, India. The general form of the distribution of matrimonial distances is one which is extremely positively skewed and leptokurtic. The percentage of intra-village marriages generally decreases from the southern areas of Maharashtra to the northern areas of the state, as does the inbreeding coefficient. This situation is in conformity with the socio-cultural norms regulating matrimonial choice in south and north India. An attempt has been made to relate the degree of inbreeding to the mean matrimonial distance and population size. The mean matrimonial distance is more useful in predicting the degree of inbreeding than population size.

  1. Conceptualizing Educational Research in Distance Education.

    Science.gov (United States)

    Watkins, Ryan; Schlosser, Charles

    2003-01-01

    Suggests a starting place for formal inquiry into distance education. Topics covered include: background on educational research and research on distance education; research paradigms that are applicable to distance education; subsystems of a distance education program; and a matrix for conceptualizing distance education research. (MES)

  2. Distance sampling methods and applications

    CERN Document Server

    Buckland, S T; Marques, T A; Oedekoven, C S

    2015-01-01

    In this book, the authors cover the basic methods and advances within distance sampling that are most valuable to practitioners and in ecology more broadly. This is the fourth book dedicated to distance sampling. In the decade since the last book published, there have been a number of new developments. The intervening years have also shown which advances are of most use. This self-contained book covers topics from the previous publications, while also including recent developments in method, software and application. Distance sampling refers to a suite of methods, including line and point transect sampling, in which animal density or abundance is estimated from a sample of distances to detected individuals. The book illustrates these methods through case studies; data sets and computer code are supplied to readers through the book’s accompanying website.  Some of the case studies use the software Distance, while others use R code. The book is in three parts.  The first part addresses basic methods, the ...

  3. Individual differences in distance perception.

    Science.gov (United States)

    Jackson, Russell E

    2009-05-07

    Distance perception is among the most pervasive mental phenomena and the oldest research topics in behavioural science. However, we do not understand well the most pervasive finding of distance perception research, that of large individual differences. There are large individual differences in acrophobia (fear of heights), which we commonly assume consists of an abnormal fear of stimuli perceived normally. Evolved navigation theory (ENT) instead suggests that acrophobia consists of a more normal fear of stimuli perceived abnormally. ENT suggests that distance perception individual differences produce major components of acrophobia. Acrophobia tested over a broad range in the present study predicted large individual differences in distance estimation of surfaces that could produce falls. This fear of heights correlated positively with distance estimates of a vertical surface-even among non-acrophobic individuals at no risk of falling and without knowledge of being tested for acrophobia. Acrophobia score predicted magnitude of the descent illusion, which is thought to reflect the risk of falling. These data hold important implications in environmental navigation, clinical aetiology and the evolution of visual systems.

  4. A possible dose-response association between distance to farmers' markets and roadside produce stands, frequency of shopping, fruit and vegetable consumption, and body mass index among customers in the Southern United States.

    Science.gov (United States)

    Jilcott Pitts, Stephanie B; Hinkley, Jedediah; Wu, Qiang; McGuirt, Jared T; Lyonnais, Mary Jane; Rafferty, Ann P; Whitt, Olivia R; Winterbauer, Nancy; Phillips, Lisa

    2017-01-11

    The association between farmers' market characteristics and consumer shopping habits remains unclear. Our objective was to examine associations among distance to farmers' markets, amenities within farmers' markets, frequency of farmers' market shopping, fruit and vegetable consumption, and body mass index (BMI). We hypothesized that the relationship between frequency of farmers' market shopping and BMI would be mediated by fruit and vegetable consumption. In 15 farmers' markets in northeastern North Carolina, July-September 2015, we conducted a cross-sectional survey among 263 farmers' market customers (199 provided complete address data) and conducted farmers' market audits. To participate, customers had to be over 18 years of age, and English speaking. Dependent variables included farmers' market shopping frequency, fruit and vegetable consumption, and BMI. Analysis of variance, adjusted multinomial logistic regression, Poisson regression, and linear regression models, adjusted for age, race, sex, and education, were used to examine associations between distance to farmers' markets, amenities within farmers' markets, frequency of farmers' market shopping, fruit and vegetable consumption, and BMI. Those who reported shopping at farmers' markets a few times per year or less reported consuming 4.4 (standard deviation = 1.7) daily servings of fruits and vegetables, and those who reported shopping 2 or more times per week reported consuming 5.5 (2.2) daily servings. There was no association between farmers' market amenities, and shopping frequency or fruit and vegetable consumption. Those who shopped 2 or more times per week had a statistically significantly lower BMI than those who shopped less frequently. There was no evidence of mediation of the relationship between frequency of shopping and BMI by fruit and vegetable consumption. More work should be done to understand factors within farmers' markets that encourage fruit and vegetable purchases.

  5. Stereo vision with distance and gradient recognition

    Science.gov (United States)

    Kim, Soo-Hyun; Kang, Suk-Bum; Yang, Tae-Kyu

    2007-12-01

    Robot vision technology is needed for the stable walking, object recognition and the movement to the target spot. By some sensors which use infrared rays and ultrasonic, robot can overcome the urgent state or dangerous time. But stereo vision of three dimensional space would make robot have powerful artificial intelligence. In this paper we consider about the stereo vision for stable and correct movement of a biped robot. When a robot confront with an inclination plane or steps, particular algorithms are needed to go on without failure. This study developed the recognition algorithm of distance and gradient of environment by stereo matching process.

  6. STRATEGIC APPLICATIONS OF DISTANCE LEARNING TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    Reviewed by Yavuz AKBULUT

    2008-10-01

    Full Text Available The book is edited by Mahbubur Rahman Syed from Minnesota State University in Mankato, USA. It is published by Information Science Reference, which is an imprint of IGI Global, an international publishing company specialized in research publications inthe fields of technology, management and information science.The book is consisted of 354 pages covering 18 chapters. Topics covered can be listed as adaptive QOS, agent-based architecture, algorithm education, asynchronous learning environments, collaborative education model, distance learning, e-Learning, hypermedia,lecture video contents, lecture video player, multicast applications and SEAMAN .

  7. Satellite Communication and Long Distance Education

    Directory of Open Access Journals (Sweden)

    Hafied Cangara

    2016-02-01

    Full Text Available Since Indonesia introduced communication satellite for telecommunication network, the satellite has brought a number of advantages for national development in various areas, such as telephone network, mass media development, business, education, politics, security and national defence as well as regional and international cooperation. In education, satellite communication could be used for long-distance learning as implemented by 13 state universities in eastern parts of Indonesia. It is also possible to develop the Open University System in teaching and learning process, particularly since the internet technology has been intensively used

  8. Flow Distances on Open Flow Networks

    CERN Document Server

    Guo, Liangzhu; Shi, Peiteng; Wang, Jun; Huang, Xiaohan; Zhang, Jiang

    2015-01-01

    Open flow network is a weighted directed graph with a source and a sink, depicting flux distributions on networks in the steady state of an open flow system. Energetic food webs, economic input-output networks, and international trade networks, are open flow network models of energy flows between species, money or value flows between industrial sectors, and goods flows between countries, respectively. Flow distances (first-passage or total) between any given two nodes $i$ and $j$ are defined as the average number of transition steps of a random walker along the network from $i$ to $j$ under some conditions. They apparently deviate from the conventional random walk distance on a closed directed graph because they consider the openness of the flow network. Flow distances are explicitly expressed by underlying Markov matrix of a flow system in this paper. With this novel theoretical conception, we can visualize open flow networks, calculating centrality of each node, and clustering nodes into groups. We apply fl...

  9. Asymmetric distances for binary embeddings.

    Science.gov (United States)

    Gordo, Albert; Perronnin, Florent; Gong, Yunchao; Lazebnik, Svetlana

    2014-01-01

    In large-scale query-by-example retrieval, embedding image signatures in a binary space offers two benefits: data compression and search efficiency. While most embedding algorithms binarize both query and database signatures, it has been noted that this is not strictly a requirement. Indeed, asymmetric schemes that binarize the database signatures but not the query still enjoy the same two benefits but may provide superior accuracy. In this work, we propose two general asymmetric distances that are applicable to a wide variety of embedding techniques including locality sensitive hashing (LSH), locality sensitive binary codes (LSBC), spectral hashing (SH), PCA embedding (PCAE), PCAE with random rotations (PCAE-RR), and PCAE with iterative quantization (PCAE-ITQ). We experiment on four public benchmarks containing up to 1M images and show that the proposed asymmetric distances consistently lead to large improvements over the symmetric Hamming distance for all binary embedding techniques.

  10. Ghost imaging with broad distance

    Institute of Scientific and Technical Information of China (English)

    段德洋; 张路; 杜少将; 夏云杰

    2015-01-01

    We present a scheme that is able to achieve the ghost imaging with broad distance. The physical nature of our scheme is that the different wavelength beams are separated in free space by an optical media according to the slow light or dispersion principle. Meanwhile, the equality of the optical distance of the two light arms is not violated. The photon correlation is achieved by the rotating ground glass plate (RGGP) and spatial light modulator (SLM), respectively. Our work shows that a monochromic ghost image can be obtained in the case of RGGP. More importantly, the position (or distance) of the object can be ascertained by the color of the image. Thus, the imaging and ranging processes are combined as one process for the first time to the best of our knowledge. In the case of SLM, we can obtain a colored image regardless of where the object is.

  11. Euclidean distance geometry an introduction

    CERN Document Server

    Liberti, Leo

    2017-01-01

    This textbook, the first of its kind, presents the fundamentals of distance geometry:  theory, useful methodologies for obtaining solutions, and real world applications. Concise proofs are given and step-by-step algorithms for solving fundamental problems efficiently and precisely are presented in Mathematica®, enabling the reader to experiment with concepts and methods as they are introduced. Descriptive graphics, examples, and problems, accompany the real gems of the text, namely the applications in visualization of graphs, localization of sensor networks, protein conformation from distance data, clock synchronization protocols, robotics, and control of unmanned underwater vehicles, to name several.  Aimed at intermediate undergraduates, beginning graduate students, researchers, and practitioners, the reader with a basic knowledge of linear algebra will gain an understanding of the basic theories of distance geometry and why they work in real life.

  12. Virtual bioinformatics distance learning suite*.

    Science.gov (United States)

    Tolvanen, Martti; Vihinen, Mauno

    2004-05-01

    Distance learning as a computer-aided concept allows students to take courses from anywhere at any time. In bioinformatics, computers are needed to collect, store, process, and analyze massive amounts of biological and biomedical data. We have applied the concept of distance learning in virtual bioinformatics to provide university course material over the Internet. Currently, we provide two fully computer-based courses, "Introduction to Bioinformatics" and "Bioinformatics in Functional Genomics." Here we will discuss the application of distance learning in bioinformatics training and our experiences gained during the 3 years that we have run the courses, with about 400 students from a number of universities. The courses are available at bioinf.uta.fi.

  13. The Distance Geometry of Music

    CERN Document Server

    Demaine, Erik D; Meijer, Henk; Rappaport, David; Taslakian, Perouz; Toussaint, Godfried T; Winograd, Terry; Wood, David R

    2007-01-01

    We demonstrate relationships between the classic Euclidean algorithm and many other fields of study, particularly in the context of music and distance geometry. Specifically, we show how the structure of the Euclidean algorithm defines a family of rhythms which encompass over forty timelines (\\emph{ostinatos}) from traditional world music. We prove that these \\emph{Euclidean rhythms} have the mathematical property that their onset patterns are distributed as evenly as possible: they maximize the sum of the Euclidean distances between all pairs of onsets, viewing onsets as points on a circle. Indeed, Euclidean rhythms are the unique rhythms that maximize this notion of \\emph{evenness}. We also show that essentially all Euclidean rhythms are \\emph{deep}: each distinct distance between onsets occurs with a unique multiplicity, and these multiplicies form an interval $1,2,...,k-1$. Finally, we characterize all deep rhythms, showing that they form a subclass of generated rhythms, which in turn proves a useful prop...

  14. Servant Leadership Through Distance Learning: A Case Study

    OpenAIRE

    RUSSELL, Eric James

    2013-01-01

    This qualitative study explored the influence a distance learning servant leadership course had on the emergency service students’ understanding of leadership. The research study utilized a case study design in order to tell the story of the lived experiences of the participants. The setting for the study was a state university in Utah, with the six participants being declared, undergraduate emergency services majors that underwent a 15-week distance learning servant leadership class. The d...

  15. Servant Leadership Through Distance Learning: A Case Study

    OpenAIRE

    Eric James RUSSELL

    2013-01-01

    This qualitative study explored the influence a distance learning servant leadership course had on the emergency service students’ understanding of leadership. The research study utilized a case study design in order to tell the story of the lived experiences of the participants. The setting for the study was a state university in Utah, with the six participants being declared, undergraduate emergency services majors that underwent a 15-week distance learning servant leadership class. The d...

  16. The Foundations of Technology Distance Education: A Review of the Literature to 2001

    Science.gov (United States)

    Schulte, Marthann

    2011-01-01

    Distance education is a very popular and intriguing area in the present realm of education. Institutions of higher learning throughout the United States and around the world are quickly embracing distance education to serve thousands of students. This literature review of the foundations of technology distance education culminates in the year…

  17. ACTS for distance education in developing countries

    Science.gov (United States)

    Kalu, A; Ventre, G.

    1995-01-01

    The need for electrical energy supply in the rural communities of developing countries has been well documented. Equally well known is the potential for photovoltaic in cost effectively meeting this need. A major impediment to fulfilling the need is the lack of indigenous personnel with a knowledgeof photovoltaic systems, and the associated infrastructure required to implement project. Various delivery schemes for providing the needed training to developing countries personnel have been investigated. Various train methods and programs that have been employed to remedy the problem have had significant drawbacks in terms of cost, consistency, impact, reach, and sustainability. The hypothesis to be tested in this project posits that satellite-based distance education using ACTS technologies can overcome these impediments. The purpose of the project is to investigate the applicability of the ACTS satellite in providing distance education in photovoltaic systems to developing countries and rural communities. An evaluation of the cost effectiveness of using ACTS unique technologies to overcome identified problems shall be done. The limitations of ACTS in surmounting distance education problems in developing countries shall be investigated. This project will, furthermore, provide training to Savannah State College faculty in photovoltaic (PV) systems and in distance education configurations and models. It will also produce training materials adequate for use in PV training programs via distance education. Savannah State College will, as a consequence become well equipped to play a leading role in the training of minority populations in photovoltaic systems and other renewables through its Center for Advanced Water Technology and Energy Systems. This communication provides the project outline including the specific issues that will be investigated during the project. Also presented i the project design which covers the participations of the various components of a network

  18. Adaptive Distance Protection for Microgrids

    DEFF Research Database (Denmark)

    Lin, Hengwei; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

    2015-01-01

    Due to the increasing penetration of distributed generation resources, more and more microgrids can be found in distribution systems. This paper proposes a phasor measurement unit based distance protection strategy for microgrids in distribution system. At the same time, transfer tripping scheme...... is adopted to accelerate the tripping speed of the relays on the weak lines. The protection methodology is tested on a mid-voltage microgrid network in Aalborg, Denmark. The results show that the adaptive distance protection methodology has good selectivity and sensitivity. What is more, this system also has...

  19. Fast Exact Euclidean Distance (FEED) Transformation

    NARCIS (Netherlands)

    Schouten, Theo; Broek, van den Egon; Kittler, J.; Petrou, M.; Nixon, M.

    2004-01-01

    Fast Exact Euclidean Distance (FEED) transformation is introduced, starting from the inverse of the distance transformation. The prohibitive computational cost of a naive implementation of traditional Euclidean Distance Transformation, is tackled by three operations: restriction of both the number o

  20. The Future of Distance Education.

    Science.gov (United States)

    Saba, Farhad

    2000-01-01

    Examines factors that will influence how distance education is practiced in the first few decades of this new century. Discusses developments in digital technology; the exponential growth of knowledge about the brain, as well as physiology, chemistry, and psychology of learning; the system relationship between individual learners and instructors;…

  1. Using Podcasts in Distance Education

    Science.gov (United States)

    Koppelman, Herman

    2013-01-01

    This paper discusses three possible ways of applying podcasts in distance education: podcasts of recordings of virtual classes, podcasts produced for specific pedagogical aims, and podcasts produced by external organizations. Through a survey we gained insight in the (until now limited) experiences of our distant students with podcasts, and also…

  2. Distance, Lending Relationships, and Competition

    NARCIS (Netherlands)

    Degryse, H.A.; Ongena, S.

    2003-01-01

    A recent string of theoretical papers has highlighted the importance of geographical distance in explaining loan rates for small firms.Lenders located in the vicinity of small firms face significantly lower transportation and monitoring costs, and hence wield considerable market power, if competing

  3. Favourite distances in high dimensions

    CERN Document Server

    Swanepoel, Konrad J

    2011-01-01

    Let $S$ be a set of $n$ points in $d$-dimensional Euclidean space. Assign to each $x\\in S$ an arbitrary distance $r(x)>0$. Let $e_r(x,S)$ denote the number of points in $S$ at distance $r(x)$ from $x$. Avis, Erd\\"os and Pach (1988) introduced the extremal quantity $f_d(n)=\\max\\sum_{x\\in S}e_r(x,S)$, where the maximum is taken over all $n$-point sets $S$ in $d$-dimensional space and all assignments $r\\colon S\\to(0,\\infty)$ of distances. We give a quick derivation of the asymptotics of the error term of $f_d(n)$ using only the analogous asymptotics of the maximum number of unit distance pairs in a set of $n$ points, which improves on previous results of Avis, Erd\\"os and Pach (1988) and Erd\\"os and Pach (1990). Then we prove a stability result for $d\\geq 4$, asserting that if $(S,r)$ with $|S|=n$ satisfies $e_r(S)=f_d(n)-o(n^2)$, then, up to $o(n)$ points, $S$ is a Lenz construction with $r$ constant. Finally we use stability to show that for $n$ sufficiently large (depending on $d$) the pairs $(S,r)$ that atta...

  4. Lessons in Developing Distance Learning.

    Science.gov (United States)

    Gant, Lenora Peters

    1996-01-01

    Describes the use of video teletraining (VTT) for distance learning in the Department of Defense. Topics include planning and organizing the VTT facility, staff development, site facilitators, the necessity of protocol, instructional design and development strategies, student involvement and interactivity, and evaluation and assessment. (LRW)

  5. Communication Barriers in Distance Education

    Science.gov (United States)

    Isman, Aytekin; Dabaj, Fahme; Altinay, Fahriye; Altinay, Zehra

    2003-01-01

    Communication is a key concept as being the major tool for people in order to satisfy their needs. It is an activity which refers as process and effective communication requires qualified communication with the elimination of communication barriers. As it is known, distance education is a new trend by following contemporary facilities and tools…

  6. Distance Learning: Untried and Untrue

    Science.gov (United States)

    Halfond, Jay A.

    2010-01-01

    G. K. Chesterton famously once said: "Christianity has not been tried and found wanting; it has been found difficult and not tried." This, the author believes, applies to distance learning as well. There is far too much self-congratulatory hyperbole about the growth and pervasiveness of online learning--which exaggerates reality and overlooks the…

  7. Curriculum Control in Distance Education.

    Science.gov (United States)

    Chesterton, Paul

    1985-01-01

    The nature of distance education is to shift the locus of curriculum control toward the institution and its staff and away from the students. This imposes a responsibility on the institution to examine and evaluate the values and assumptions underlying the decision-making and the implications of the patterns of control that emerge. (Author/MSE)

  8. Distance, Lending Relationships and Competition

    NARCIS (Netherlands)

    Degryse, H.A.; Ongena, S.

    2002-01-01

    A recent string of theoretical papers highlights the importance of geographical distance in explaining pricing and availability of loans to small firms.Lenders located in the vicinity of small firms have significantly lower monitoring and transaction costs, and hence considerable market power if com

  9. On Maximum Lee Distance Codes

    OpenAIRE

    Alderson, Tim L.; Svenja Huntemann

    2013-01-01

    Singleton-type upper bounds on the minimum Lee distance of general (not necessarily linear) Lee codes over ℤq are discussed. Two bounds known for linear codes are shown to also hold in the general case, and several new bounds are established. Codes meeting these bounds are investigated and in some cases characterised.

  10. Video Surveillance using Distance Maps

    NARCIS (Netherlands)

    Schouten, Theo E.; Kuppens, Harco C.; Broek, van den Egon L.; Kehtarnavaz, Nasser; Laplante, Phillip A.

    2006-01-01

    Human vigilance is limited; hence, automatic motion and distance detection is one of the central issues in video surveillance. Hereby, many aspects are of importance, this paper specially addresses: efficiency, achieving real-time performance, accuracy, and robustness against various noise factors.

  11. Gesture Interaction at a Distance

    NARCIS (Netherlands)

    Fikkert, F.W.

    2010-01-01

    The aim of this work is to explore, from a perspective of human behavior, which gestures are suited to control large display surfaces from a short distance away; why that is so; and, equally important, how such an interface can be made a reality. A well-known example of the type of interface that is

  12. The Perception of Ideological Distance

    NARCIS (Netherlands)

    Granberg, Donald; Brown, Thad A.

    1992-01-01

    Data from national election studies in Britain, the Netherlands, Sweden, and the U.S. were analyzed to test hypotheses concerning the perception of ideological distance between parties and candidates. The first hypothesis, derived from Sherif's social judgment theory and Heider's balance theory, was

  13. Isolation by distance, web service

    Directory of Open Access Journals (Sweden)

    Bohonak Andrew J

    2005-03-01

    Full Text Available Abstract Background The population genetic pattern known as "isolation by distance" results from spatially limited gene flow and is a commonly observed phenomenon in natural populations. However, few software programs exist for estimating the degree of isolation by distance among populations, and they tend not to be user-friendly. Results We have created Isolation by Distance Web Service (IBDWS a user-friendly web interface for determining patterns of isolation by distance. Using this site, population geneticists can perform a variety of powerful statistical tests including Mantel tests, Reduced Major Axis (RMA regression analysis, as well as calculate FST between all pairs of populations and perform basic summary statistics (e.g., heterozygosity. All statistical results, including publication-quality scatter plots in Postscript format, are returned rapidly to the user and can be easily downloaded. Conclusion IBDWS population genetics analysis software is hosted at http://phage.sdsu.edu/~jensen/ and documentation is available at http://www.bio.sdsu.edu/pub/andy/IBD.html. The source code has been made available on Source Forge at http://sourceforge.net/projects/ibdws/.

  14. Video surveillance using distance maps

    NARCIS (Netherlands)

    Schouten, Theo E.; Kuppens, Harco C.; van den Broek, Egon; Kehtarnavaz, Nasser; Laplante, Phillip A,

    2006-01-01

    Human vigilance is limited; hence, automatic motion and distance detection is one of the central issues in video surveillance. Hereby, many aspects are of importance, this paper specially addresses: efficiency, achieving real-time performance, accuracy, and robustness against various noise factors.

  15. Effect of nuclear factor-kappa B decoy oligodeoxynncleotides on respiratory function and cytokine expression after severe lung contusion in rabbits%NF-kB双链寡脱氧核苷酸圈套对严重肺挫伤兔呼吸功能及炎性因子表达的影响

    Institute of Scientific and Technical Information of China (English)

    方丹青; 于涛; 万丽

    2010-01-01

    Objective To explore the effect of nuclear factor-kappa B (NF-κB) decoy oligode-oxynucleotides (ODN) on respiratory function and expressions of IL-1β and IL-13 in serum following se-vere lung contusion in rabbits. Methods A total of 40 New-Zealand rabbits were randomly divided into four groups, ie, severe lung contusion group (Group A, n=12), severe lung contusion with NF-κB scrambled decoy ODN intervention group (Group B, n=12), severe lung contusion with sense NF- B de-coy ODN intervention group (Group C, n=12) and normal control group (Group D, n =4). After the contusion model was set up, the sense and scrambled NF-κB decoy ODN were infused into the rabbits via the jugular veins in different groups, with 20 g per experimental rabbit. After contusion, respiratory fre-quency, tidal volume, airway pressure, respiration flow rate curve and end expiration nitric oxide concen-tration were detected at 1, 2, 3 and 4 hours. The expressions of IL-1β and IL-13 in serum were observed by means of ELISA. Results After sense NF-κB decoy ODN intervention, alveolar ventilation, arteri-al PO_2 and pulmonary compliance were improved, compared with Group A and Group B, with statistical difference (P0.01).血清炎性因子IL-1β在挫伤后1 h升至高峰,并持续至实验结束,IL-13的表达在肺挫伤后1 h下降,4 h降至最低值.经正链decoy ODN治疗后可使挫伤后显著升高的IL-1β明显降低,而IL-13的表达维持于高水平,与挫伤组、杂链组比较,差异有统计学意义(P<0.01).结论 在严重胸外伤肺挫伤早期呼吸功能出现损害时给予NF-κB正链decoy ODN治疗,对挫伤肺通气功能、换气功能、呼吸力学有明显的保护作用,且血清炎性因子IL-1β的表达减少,IL-13表达升高.

  16. Joint Parameter Estimation of the Target and Decoy within the Radar Beam Based on Improved MCMC%基于改进MCMC的波束内目标与诱饵联合参数估计

    Institute of Scientific and Technical Information of China (English)

    宋志勇; 肖怀铁; 祝依龙; 卢再奇

    2012-01-01

    波束内目标与诱饵的参数估计是导引头正确实现目标分选、完成波束指向调整与精确跟踪的必要条件.目标与诱饵的“紧密接近”导致接收回波混叠,使得常规参数测量与估计方法失效.基于实际采样处理中目标回波能量会“溢出”到相邻匹配滤波采样点这一信号模型,通过贝叶斯原理从观测的条件似然以及未知参数的先验分布获取待估计参数的后验概率分布,采用Markov Chain Monte Carlo (MCMC)方法中的Metropolis-Hastings (M-H)抽样算法联合估计目标与诱饵的相关参数,并根据拖曳式诱饵干扰对抗的特点对M-H抽样进行了改进.各种典型干扰条件及动态攻击场景下的仿真试验表明了本文方法的有效性.%The parameter estimation of the target and towed radar active decoy (TRAD) within the radar beam is the necessary condition for radar seeker to realize target selection and achieve the boresight steering adjust and accurate tracking. The "closely spaced" target and decoy make radar echoes abased and the traditional method for parameter measurement and estimation fail. Based on the signal model, that the energy of single target will spill over to adjacent matched filter sampling points when the output of matched filter of radar seeker is sampled actually. Bayesian theory is adopted to obtain the posterior probability density function of estimated parameters from the conditional likelihood function of the observation and the prior distribution of unknown parameters in this paper. Then the Metropolis-Hastings (M-H) sampling algorithm belonged to Markov Chain Monte Carlo (MCMC) is utilized to estimate parameters of target and decoy jointly. At the same time, based on the jamming model and characteristics of TRAD, the M-H sampling is improved. The simulation results under different jamming conditions and dynamic attack scenarios illustrate the performance of proposed method.

  17. A Streaming Distance Transform Algorithm for Neighborhood-Sequence Distances

    Directory of Open Access Journals (Sweden)

    Nicolas Normand

    2014-09-01

    Full Text Available We describe an algorithm that computes a “translated” 2D Neighborhood-Sequence Distance Transform (DT using a look up table approach. It requires a single raster scan of the input image and produces one line of output for every line of input. The neighborhood sequence is specified either by providing one period of some integer periodic sequence or by providing the rate of appearance of neighborhoods. The full algorithm optionally derives the regular (centered DT from the “translated” DT, providing the result image on-the-fly, with a minimal delay, before the input image is fully processed. Its efficiency can benefit all applications that use neighborhood- sequence distances, particularly when pipelined processing architectures are involved, or when the size of objects in the source image is limited.

  18. DEMANDING NEED OF GROWING TECHNOLOGIES IN DISTANCE LEARNING SYSTEM

    Directory of Open Access Journals (Sweden)

    Amtul HAFEEZ

    2014-10-01

    Full Text Available In distance education system use of different media enable the learners to start the course of study independently. The appearance of the internet and the expansion of web have now changed distance learning from a broadcasting way to an interactive way, and allowed connecting the learners and instructors who are geographically divided. Technological advances have created a paradigm shift in education and the definition of distance learning, as described by James Morrison (1996, who states that telecommunications, software, and the Internet eliminate walls and boundaries. In addition, he states that an increasing number of students want and need non-traditional, flexible schedules. Main findings of the study revealed that majority of the distance learners need growing technologies to interact with the tutors and peers for academic guidance and use of latest technologies make distance learners more up to date and helpful for better academic achievements. Majority of the students agreed that without any training distance learner cannot use growing technologies. It was recommended that AIOU may take steps to organize a specific website for the MS/M.phil and Ph.D scholars so that they can easily interact with peers and tutors. A comprehensive training programme may be launched to enable the tutors for using growing technologies so that they can facilitate the learners by using latest methods of teaching. Virtual classrooms can be started along with the workshops. Students and academicians of education department may use latest technologies and internet softwares which can be helpful for academic purpose.

  19. Effective Teaching in Distance Education. ERIC Digest.

    Science.gov (United States)

    Mielke, Dan

    Distance education is an alternative method for delivering academic course work to students unable to attend traditional campus-based classes. This Digest presents information on the many forms of distance education and keys to successful teaching with distance education. Distance education is a method of education in which the learner is…

  20. The intractability of computing the Hamming distance

    NARCIS (Netherlands)

    Manthey, Bodo; Reischuk, Rüdiger

    2005-01-01

    Given a string x and a language L, the Hamming distance of x to L is the minimum Hamming distance of x to any string in L. The edit distance of a string to a language is analogously defined. First, we prove that there is a language in $AC^0$ such that both Hamming and edit distance to this language

  1. History and Heritage in Distance Education

    Science.gov (United States)

    Anderson, Bill; Simpson, Mary

    2012-01-01

    Distance education's history is a tremendous resource for all involved in distance education. Some aspects of that history provide enduring touchstones for present distance educators, creating a heritage that should not be overlooked as distance education continues to develop and expand. In this article we draw on the concept of generational…

  2. Determining distances using asteroseismic methods

    CERN Document Server

    Aguirre, V Silva; Basu, S; Campante, T L; Chaplin, W J; Huber, D; Miglio, A; Serenelli, A M; WG#1, KASC

    2012-01-01

    Asteroseismology has been extremely successful in determining the properties of stars in different evolutionary stages with a remarkable level of precision. However, to fully exploit its potential, robust methods for estimating stellar parameters are required and independent verification of the results is needed. In this talk, I present a new technique developed to obtain stellar properties by coupling asteroseismic analysis with the InfraRed Flux Method. Using two global seismic observables and multi-band photometry, the technique determines masses, radii, effective temperatures, bolometric fluxes, and thus distances for field stars in a self-consistent manner. Applying our method to a sample of solar-like oscillators in the {\\it Kepler} field that have accurate {\\it Hipparcos} parallaxes, we find agreement in our distance determinations to better than 5%. Comparison with measurements of spectroscopic effective temperatures and interferometric radii also validate our results, and show that our technique can ...

  3. Managerial Distance and Virtual Ownership

    DEFF Research Database (Denmark)

    Hansmann, Henry; Thomsen, Steen

    Industrial foundations are autonomous nonprofit entities that own and control one or more conventional business firms. These foundations are common in Northern Europe, where they own a number of internationally prominent companies. Previous studies have indicated, surprisingly, that companies con......, but corporate governance and fiduciary behavior more generally....... on differences among the industrial foundations themselves. We work with a rich data set comprising 113 foundation-owned Danish companies over the period 2003-2008. We focus in particular on a composite structural factor that we term “managerial distance.” We propose this as a measure of the extent to which......-seeking outside owners of the company. Consistent with this hypothesis, our empirical analysis shows a positive, significant, and robust association between managerial distance and the economic performance of foundation owned companies. The findings appear to illuminate not just foundation governance...

  4. Theological Librarianship from a Distance

    Directory of Open Access Journals (Sweden)

    Melody Diehl Detar

    2015-08-01

    Full Text Available This essay examines distance theological librarianship and the field’s suitability for remote librarians. A brief introduction to the landscape of online programs in theological education is followed by an overview of virtual librarianship and how theological librarians may serve students while working from a distance themselves. The essay then describes a method for initiating a remote librarian position in a theological library context, and then reviews the steps of determining whether remote work is feasible and desirable at an institution, approaching leadership with a plan, setting up a trial remote work period, and assessing its success. Particular emphasis is given to communication expectations, modes of virtual reference and instruction, campus committee service and meaningful ways of remaining part of the campus community.

  5. Moral distance in dictator games

    Directory of Open Access Journals (Sweden)

    Fernando Aguiar

    2008-04-01

    Full Text Available We perform an experimental investigation using a dictator game in which individuals must make a moral decision --- to give or not to give an amount of money to poor people in the Third World. A questionnaire in which the subjects are asked about the reasons for their decision shows that, at least in this case, moral motivations carry a heavy weight in the decision: the majority of dictators give the money for reasons of a consequentialist nature. Based on the results presented here and of other analogous experiments, we conclude that dicator behavior can be understood in terms of moral distance rather than social distance and that it systematically deviates from the egoism assumption in economic models and game theory. %extit{JEL}: A13, C72, C91

  6. Students’ Role in Distance Learning

    OpenAIRE

    Beers Fägersten, Kristy

    2008-01-01

    1. IntroductionMuch of the support that students have in a traditional classroom is absent in a distance learning course. In the traditional classroom, the learner is together with his or her classmates and the teacher; learning is socially embedded. Students can talk to each other and may learn from each other as they go through the learning process together. They also witness the teacher’s expression of the knowledge firsthand. The class participants communicate to each other not ...

  7. Hardware Euclidean Distance Transform Implementation

    Institute of Scientific and Technical Information of China (English)

    XIE Ying-hua; ZENG Pei-feng; TANG Li-ping

    2004-01-01

    Based on an efficient algorithm of Euclidean distance transform for binary images, a circuit of O(N2) size is proposed. With in-place calculation, both the intermediate data storing and the result output use the same memory with the input data. This reduces the amount of memory largely. By replacing multipliers with counters, comparators, and adders, the circuit size is further reduced and its calculation speed is improved also.

  8. Distance effects in electrochemical micromachining

    OpenAIRE

    2016-01-01

    Considering exponential dependence of currents on double-layer voltage and the feedback effect of the electrolyte resistance, a distance effect in electrochemical micromachining is found, namely that both time constant and double-layer voltage depend on the separation of electrodes. The double-layer voltage is the real voltage used in processing. Under DC voltage, the apparent voltages between two electrodes are constant for different separations, but the real voltages change with the separat...

  9. The Magnetotail at Lunar Distance

    Science.gov (United States)

    Sibeck, D. G.

    2015-12-01

    This presentation reviews some of the single-point observations of the magnetotail at lunar distances made by ALSEP, Explorer 33, 35, ISEE-3, and Geotail that form the framework for interpreting more recent dual-spacecraft ARTEMIS observations. Earth's distant magnetotail flaps, twists, and flattens in response to variations in the solar wind flow direction and interplanetary magnetic field (IMF) orientation. It may even disappear leaving nothing more than a wake during strongly northward IMF orientations. Standing slow mode expansion fans provide for a gradual transition between magnetotail lobe and magnetosheath plasma and magnetic field parameters. The distant neutral line may at times reside at lunar distances, creating jets of sunward-streaming plasma within the cislunar plasma sheet and layers of streaming energetic particles on its boundaries. Reconnection at near-Earth neutral lines releases antisunward-moving plasmoids that transit lunar distances, briefly expanding the diameter of the plasma sheet and magnetotail. Taken as a whole, the distant magnetotail is a fascinating plasma laboratory and a region of great important to the magnetosphere.

  10. Support Services for Distance Education

    Directory of Open Access Journals (Sweden)

    Sandra Frieden

    1999-01-01

    Full Text Available The creation and operation of a distance education support infrastructure requires the collaboration of virtually all administrative departments whose activities deal with students and faculty, and all participating academic departments. Implementation can build on where the institution is and design service-oriented strategies that strengthen institutional support and commitment. Issues to address include planning, faculty issues and concerns, policies and guidelines, approval processes, scheduling, training, publicity, information-line operations, informational materials, orientation and registration processes, class coordination and support, testing, evaluations, receive site management, partnerships, budgets, staffing, library and e-mail support, and different delivery modes (microwave, compressed video, radio, satellite, public television/cable, video tape and online. The process is ongoing and increasingly participative as various groups on campus begin to get involved with distance education activities. The distance education unit must continuously examine and revise its processes and procedures to maintain the academic integrity and service excellence of its programs. It’s a daunting prospect to revise the way things have been done for many years, but each department has an opportunity to respond to new ways of serving and reaching students.

  11. Fingerprinting with Minimum Distance Decoding

    CERN Document Server

    Lin, Shih-Chun; Gamal, Hesham El

    2007-01-01

    This work adopts an information theoretic framework for the design of collusion-resistant coding/decoding schemes for digital fingerprinting. More specifically, the minimum distance decision rule is used to identify 1 out of t pirates. Achievable rates, under this detection rule, are characterized in two distinct scenarios. First, we consider the averaging attack where a random coding argument is used to show that the rate 1/2 is achievable with t=2 pirates. Our study is then extended to the general case of arbitrary $t$ highlighting the underlying complexity-performance tradeoff. Overall, these results establish the significant performance gains offered by minimum distance decoding as compared to other approaches based on orthogonal codes and correlation detectors. In the second scenario, we characterize the achievable rates, with minimum distance decoding, under any collusion attack that satisfies the marking assumption. For t=2 pirates, we show that the rate $1-H(0.25)\\approx 0.188$ is achievable using an ...

  12. Platelet function and fibrinolytic activity following distance running.

    Science.gov (United States)

    Knudsen, J B; Brodthagen, U; Gormsen, J; Jordal, R; Nørregaard-Hansen, K; Paulev, P E

    1982-11-01

    6 long distance runners from the Danish marathon elite and 6 non-runners completed test runs of 28 and 12 km, respectively. Distance runners and non-runners showed the same responses in platelet function. We found a significant decrease in ADP induced platelet aggregability, a decreased serotonin release induced by ADP and collagen and an increase in platelet factor 4 immediately following the run. The antithrombin III levels remained constant. Euglobulin lysis time was shortened (by approximately 50%) and the plasminogen levels significantly increased. The last 2 findings indicate an equal increase in fibrinolytic activity during distance running in both groups. While short term, strenuous exercise induces platelet hyperaggregation, long term distance running induces a state of exhaustion of platelet aggregation capacity.

  13. Editorial ~ Global Diversity of Distance Education

    OpenAIRE

    2001-01-01

    In a panel presentation at the recent International Council for Open and Distance Education (ICDE) world conference in Dusseldorf, Germany, I had the opportunity to explain the unique role and mission of International Review of Research in Open and Distance Learning (IRRODL) vis – vis our more established sister journals: Open Praxis, Open Learning, Journal of Distance Education, Distance Education, and American Journal of Distance Education. Although all of these journals share a common comm...

  14. Distance caregiving a family member with cancer: A review of the literature on distance caregiving and recommendations for future research.

    Science.gov (United States)

    Douglas, Sara L; Mazanec, Polly; Lipson, Amy; Leuchtag, Mary

    2016-04-10

    Distance caregivers (DCGs) are a growing phenomenon in the United States Family members are struggling to provide care to loved ones with chronic illnesses such as cancer, from a distance. Unlike local caregiving research, distance caregiving research is limited and inconsistent definitions of distance make it difficult to compare studies. To date, DCGs have not been afforded the opportunities for educational and emotional support that local caregivers have received from the health care teams. Because they are not usually present at medical appointments, DCGs do not receive first-hand information from the health care team about the patient's condition, disease progression, and/or treatment options. These caregivers report feeling left out of important family discussions. They experience anxiety related to the uncertainty of the family members' well-being and guilt related to not being available to help local caregivers more. The challenges of distance caregiving are especially evident when the distance caregiver has a parent with advanced cancer. Family-centered care, attending to the needs of the whole family regardless of their geographic location is critical for quality cancer care. In this manuscript, the sparse literature on distance caregiving is reviewed. Recommendations for future research and for the development of creative technologically advanced interventions for this underserved caregiving population are suggested.

  15. Time-delay Cosmography: Increased Leverage with Angular Diameter Distances

    CERN Document Server

    Jee, Inh; Suyu, Sherry H; Huterer, Dragan

    2015-01-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the cosmic microwave background data of Planck improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat $\\Lambda$CDM model by a factor of two. Therefore, previous forec...

  16. Time-delay cosmography: increased leverage with angular diameter distances

    Science.gov (United States)

    Jee, I.; Komatsu, E.; Suyu, S. H.; Huterer, D.

    2016-04-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used in forecasting cosmographic constraints. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the Planck's measurements of the cosmic microwave background anisotropies improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat ΛCDM model by a factor of two. Therefore, previous forecasts for the statistical power of time-delay systems were overly pessimistic, i.e., time-delay systems are more powerful than previously appreciated.

  17. Radio and distance learning in Pakistan.

    Science.gov (United States)

    Abbas, R

    1987-01-01

    Radio is a powerful communication vehicle in Pakistan able to reach 3/4 of urban and 2/3 of rural households. Until 1974, most radio broadcasts of the Pakistan Broadcasting Corporation, a state monopoly, were in the categories of music, drama, and features; news and current affairs; and religious broadcasts. The Allama Iqbal Open University (AIOU), a distance learning educational institution, was established through an act of the Pakistan Parliament in 1974 and is the only institution in the country to use radio broadcasts for its curriculum. Also established in 1974 within the AIOU was the Institute of Educational Technology (IET). The IET channels the transmission and flow of well-designed educational messages and lessons from the teachers to the students by employing distance teaching methodology that seeks to reinforce students' weekly lessons. IET closely integrates its activities within the University's academic departments. IET staff members not only participate in the development of course curriculum and syllabi, but also help to identify course content needing reinforcement through radio. While the teachers at AIOU convert the course curricula into distance-learning self-study activity-oriented correspondence texts, IET producers transcribe these scripts into actual production scripts. Feedback from students and findings of the University's Research and Statistical Cell are used to make revisions in the scripts. The AIOU enrolls an average of 100,000 students each year. Expansion is being limited only by the costs of purchasing time from the Pakistan Broadcasting Corporation (Rs 2000 for a 15-minute lesson) and the availability of appropriate time slots.

  18. Distance learning through synchronous interactive television.

    Science.gov (United States)

    Hall, Janis L

    2007-01-01

    The advent and popularity of asynchronous online learning has somewhat obscured a standby technology developed over the last two decades. Interactive videoconferencing, sometimes called "interactive television," though not as glamorous and popular a topic at distance-learning conferences, is still alive and well at many institutions. Three or four years ago, many of us were led to believe that interactive television would go the way of the dinosaurs-everything would soon be in an asynchronous format or on individual desktops. There would no longer be any need for elaborately designed classrooms, networks, and operations staff. To date, this prediction has not come true. In fact, synchronous interactive television has experienced significant growth as newer, easier, and cheaper technologies allow institutions to reach more students with less resource investment. Faculty and students, while appreciating the convenience of asynchronous delivery, still express a need for synchronous communication. This article explores the issues involved in synchronous distance education, the current technologies and proposed future developments, and best practices in terms of classroom design, faculty use, and operational issues. It is not a research article but an anecdotal case study based on Washington State University's experiences over the last 20 years in developing and adapting to new synchronous technologies and creating the support and technical infrastructure to best deliver academic courses through this medium.

  19. Max–min distance nonnegative matrix factorization

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-10-26

    Nonnegative Matrix Factorization (NMF) has been a popular representation method for pattern classification problems. It tries to decompose a nonnegative matrix of data samples as the product of a nonnegative basis matrix and a nonnegative coefficient matrix. The columns of the coefficient matrix can be used as new representations of these data samples. However, traditional NMF methods ignore class labels of the data samples. In this paper, we propose a novel supervised NMF algorithm to improve the discriminative ability of the new representation by using the class labels. Using the class labels, we separate all the data sample pairs into within-class pairs and between-class pairs. To improve the discriminative ability of the new NMF representations, we propose to minimize the maximum distance of the within-class pairs in the new NMF space, and meanwhile to maximize the minimum distance of the between-class pairs. With this criterion, we construct an objective function and optimize it with regard to basis and coefficient matrices, and slack variables alternatively, resulting in an iterative algorithm. The proposed algorithm is evaluated on three pattern classification problems and experiment results show that it outperforms the state-of-the-art supervised NMF methods.

  20. Mattig's relation and dynamical distance indicators

    CERN Document Server

    Teerikorpi, Pekka

    2016-01-01

    We discuss how the redshift (Mattig) method in Friedmann cosmology relates to dynamical distance indicators based on Newton's gravity (Teerikorpi 2011). It belongs to the class of indicators where the relevant length inside the system is the distance itself (in this case the proper metric distance). As the Friedmann model has Newtonian analogy, its use to infer distances has instructive similarities to classical dynamical distance indicators. In view of the theoretical exact linear distance-velocity law, we emphasize that it is conceptually correct to derive the cosmological distance via the route: redshift (primarily observed) --> space expansion velocity (not directly observed) --> metric distance (physical length in "cm"). Important properties of the proper metric distance are summarized.

  1. Distance Measurement Solves Astrophysical Mysteries

    Science.gov (United States)

    2003-08-01

    Location, location, and location. The old real-estate adage about what's really important proved applicable to astrophysics as astronomers used the sharp radio "vision" of the National Science Foundation's Very Long Baseline Array (VLBA) to pinpoint the distance to a pulsar. Their accurate distance measurement then resolved a dispute over the pulsar's birthplace, allowed the astronomers to determine the size of its neutron star and possibly solve a mystery about cosmic rays. "Getting an accurate distance to this pulsar gave us a real bonanza," said Walter Brisken, of the National Radio Astronomy Observatory (NRAO) in Socorro, NM. Monogem Ring The Monogem Ring, in X-Ray Image by ROSAT satellite CREDIT: Max-Planck Institute, American Astronomical Society (Click on Image for Larger Version) The pulsar, called PSR B0656+14, is in the constellation Gemini, and appears to be near the center of a circular supernova remnant that straddles Gemini and its neighboring constellation, Monoceros, and is thus called the Monogem Ring. Since pulsars are superdense, spinning neutron stars left over when a massive star explodes as a supernova, it was logical to assume that the Monogem Ring, the shell of debris from a supernova explosion, was the remnant of the blast that created the pulsar. However, astronomers using indirect methods of determining the distance to the pulsar had concluded that it was nearly 2500 light-years from Earth. On the other hand, the supernova remnant was determined to be only about 1000 light-years from Earth. It seemed unlikely that the two were related, but instead appeared nearby in the sky purely by a chance juxtaposition. Brisken and his colleagues used the VLBA to make precise measurements of the sky position of PSR B0656+14 from 2000 to 2002. They were able to detect the slight offset in the object's apparent position when viewed from opposite sides of Earth's orbit around the Sun. This effect, called parallax, provides a direct measurement of

  2. Variable Distance Angular Symbology Reader

    Science.gov (United States)

    Schramm, Harry F., Jr. (Inventor); Corder, Eric L. (Inventor)

    2006-01-01

    A variable distance angular symbology, reader utilizes at least one light source to direct light through a beam splitter and onto a target. A target may be angled relative to the impinging light beam up to and maybe even greater than 45deg. A reflected beam from the target passes through the beam splitter and is preferably directed 90deg relative to the light source through a telecentric lens to a scanner which records an image of the target such as a direct part marking code.

  3. Anxiety and Resistance in Distance Learning

    Directory of Open Access Journals (Sweden)

    Nazime Tuncay

    2010-06-01

    Full Text Available The purpose of this study was to investigate students' anxiety and resistance towards learning through distance education.Specifically, the study sought answers to the following questions: -What are the reasons of students not choosing distancelearning courses? -Which symptoms of anxiety, if any, do distance learner’s exhibit towards distance learning? Does genderhave any significant relationships with distance learners' perception of factors that affect their anxiety and resistance? A totalof 120 distance education students in Near East University were observed and 96 of them were interviewed. Computer anxiety,language anxiety, social anxiety were observed to be among the reasons of students’ resistance to distance learning.

  4. A note on the path interval distance.

    Science.gov (United States)

    Coons, Jane Ivy; Rusinko, Joseph

    2016-06-01

    The path interval distance accounts for global congruence between locally incongruent trees. We show that the path interval distance provides a lower bound for the nearest neighbor interchange distance. In contrast to the Robinson-Foulds distance, random pairs of trees are unlikely to be maximally distant from one another under the path interval distance. These features indicate that the path interval distance should play a role in phylogenomics where the comparison of trees on a fixed set of taxa is becoming increasingly important.

  5. Lightweight Distance Bounding Protocol against Relay Attacks

    Science.gov (United States)

    Kim, Jin Seok; Cho, Kookrae; Yum, Dae Hyun; Hong, Sung Je; Lee, Pil Joong

    Traditional authentication protocols are based on cryptographic techniques to achieve identity verification. Distance bounding protocols are an enhanced type of authentication protocol built upon both signal traversal time measurement and cryptographic techniques to accomplish distance verification as well as identity verification. A distance bounding protocol is usually designed to defend against the relay attack and the distance fraud attack. As there are applications to which the distance fraud attack is not a serious threat, we propose a streamlined distance bounding protocol that focuses on the relay attack. The proposed protocol is more efficient than previous protocols and has a low false acceptance rate under the relay attack.

  6. Factors Related to Rural School Administrators' Satisfaction with Distance Education

    Science.gov (United States)

    Irvin, Matthew J.; Hannum, Wallace H.; de la Varre, Claire; Farmer, Thomas W.; Keane, Julie

    2012-01-01

    The purpose of this study was to examine rural school district administrators' satisfaction with distance education in the United States and to identify factors that may contribute to their satisfaction. Telephone interviews were conducted with administrators in randomly selected rural districts across the country. Analyses revealed that students'…

  7. The Euclidean distance degree of an algebraic variety

    NARCIS (Netherlands)

    J. Draisma (Jan); Horobeţ, E. (Emil); Ottaviani, G. (Giorgio); B. Sturmfels; R.R. Thomas (Rekha)

    2016-01-01

    textabstractThe nearest point map of a real algebraic variety with respect to Euclidean distance is an algebraic function. For instance, for varieties of low-rank matrices, the Eckart–Young Theorem states that this map is given by the singular value decomposition. This article develops a theory of

  8. Servant Leadership through Distance Learning: A Case Study

    Science.gov (United States)

    Russell, Eric James

    2013-01-01

    This qualitative study explored the influence a distance learning servant leadership course had on the emergency service students' understanding of leadership. The research study utilized a case study design in order to tell the story of the lived experiences of the participants. The setting for the study was a state university in Utah, with the…

  9. Kinetic distance and kinetic maps from molecular dynamics simulation.

    Science.gov (United States)

    Noé, Frank; Clementi, Cecilia

    2015-10-13

    Characterizing macromolecular kinetics from molecular dynamics (MD) simulations requires a distance metric that can distinguish slowly interconverting states. Here, we build upon diffusion map theory and define a kinetic distance metric for irreducible Markov processes that quantifies how slowly molecular conformations interconvert. The kinetic distance can be computed given a model that approximates the eigenvalues and eigenvectors (reaction coordinates) of the MD Markov operator. Here, we employ the time-lagged independent component analysis (TICA). The TICA components can be scaled to provide a kinetic map in which the Euclidean distance corresponds to the kinetic distance. As a result, the question of how many TICA dimensions should be kept in a dimensionality reduction approach becomes obsolete, and one parameter less needs to be specified in the kinetic model construction. We demonstrate the approach using TICA and Markov state model (MSM) analyses for illustrative models, protein conformation dynamics in bovine pancreatic trypsin inhibitor and protein-inhibitor association in trypsin and benzamidine. We find that the total kinetic variance (TKV) is an excellent indicator of model quality and can be used to rank different input feature sets.

  10. Three-Distance Sequences with Three Symbols

    OpenAIRE

    SAKAMOTO, Kuniko

    2003-01-01

    We will show that every $3$ dimensional cutting sequence is a three-distance sequence, and there are uncountable many periodic or aperiodic three-distance sequences (with $3$-symbols) which are not $3$ dimensional cutting sequences.

  11. A Cognitively Grounded Measure of Pronunciation Distance

    NARCIS (Netherlands)

    Wieling, M.; Nerbonne, J.; Bloem, J.; Gooskens, C.; Heeringa, W.; Baayen, R.H.

    2014-01-01

    In this study we develop pronunciation distances based on naive discriminative learning (NDL). Measures of pronunciation distance are used in several subfields of linguistics, including psycholinguistics, dialectology and typology. In contrast to the commonly used Levenshtein algorithm, NDL is groun

  12. Economics of Distance and Online Learning Theory, Practice and Research

    Directory of Open Access Journals (Sweden)

    reviewed by TOJDE

    2009-10-01

    Full Text Available Economics of Distance and Online LearningTheory, Practice and ResearchBy William Bramble & Santosh PandaPrice: $125.00ISBN: 978-0-415-96388-6, Binding: Hardback, Publishedby: Routledge, New York, Publication Date: March 2008, Pages: 312TOJDEABOUT THE BOOKThis book provides a comprehensive overview of theorganizational models of distance and online learning froman international perspective and from the point of view ofeconomic planning, costing and management decisionmaking.The book points to directions for the further research anddevelopment in this area, and will promote furtherunderstanding and critical reflection on the part ofadministrators, practitioners and researchers of distanceeducation.The experiences and perspectives in distance education inthe US are balanced with those in other areas of the world.Table of ContentsPrefaceSECTION ONE: INTRODUCTIONChapter 1: Organizational and Cost Structures for Distanceand Online Learning, William J. Bramble and Santosh PandaSECTION TWO: PLANNING AND MANAGEMENTChapter 2: Changing Distance Education andChanging Organizational Issues, D. Randy Garrison and Heather KanukaChapter 3: Online Learning and the University, Chris Curran217Chapter 4: Virtual Schooling and Basic Education, Thomas ClarkChapter 5: Historical Perspectives on Distance Education in the United States, Paul J.Edelson and Von PittmanSECTION THREE: FUNDINGChapter 6: Funding of Distance and Online Learning in the United States, Mark J. Smithand William J. BrambleChapter 7: Funding Distance Education: A Regional Perspective, Santosh Panda andAshok GabaSECTION FOUR: COST STRUCTURES AND MODELSChapter 8: Costs and Quality of Online Learning, Alistair InglisChapter 9: Costing Virtual University Education, Insung JungChapter 10: Cost-Benefit of Student Retention Policies and Practices, Ormond SimpsonSECTION FIVE: DISTANCE TRAININGChapter 11: Cost Benefit of Online Learning, Zane Berge and Charlotte DonaldsonChapter 12: Transforming Workplace

  13. THE INFLUENCE OF WOMEN ON DISTANCE EDUCATION

    OpenAIRE

    2014-01-01

    The impact of distance education on women has been significant. Distance education has been a viable means for helping women reach their educational ambitions. Over the last 40 years distance education has increased the ease of access and control over study time. With geographical and time barriers removed, women in particular were able to add the role of student to their list of responsibilities. Women have defeated educational barriers through educational opportunities presented by distance...

  14. Distance-based classification of keystroke dynamics

    Science.gov (United States)

    Tran Nguyen, Ngoc

    2016-07-01

    This paper uses the keystroke dynamics in user authentication. The relationship between the distance metrics and the data template, for the first time, was analyzed and new distance based algorithm for keystroke dynamics classification was proposed. The results of the experiments on the CMU keystroke dynamics benchmark dataset1 were evaluated with an equal error rate of 0.0614. The classifiers using the proposed distance metric outperform existing top performing keystroke dynamics classifiers which use traditional distance metrics.

  15. Distance effects in electrochemical micromachining

    Science.gov (United States)

    Xu, Lizhong; Pan, Yue; Zhao, Chuanjun

    2016-09-01

    Considering exponential dependence of currents on double-layer voltage and the feedback effect of the electrolyte resistance, a distance effect in electrochemical micromachining is found, namely that both time constant and double-layer voltage depend on the separation of electrodes. The double-layer voltage is the real voltage used in processing. Under DC voltage, the apparent voltages between two electrodes are constant for different separations, but the real voltages change with the separations. Small separations exert substantial effects on the real voltages. Accordingly, a DC-voltage small-separation electrochemical micromachining technique was proposed. The double-layer voltage drops sharply as the small separation increases. Thus, the electrochemical reactions are confined to electrode regions in very close proximity even under DC voltage. The machining precision can be significantly enhanced by reducing the voltage and separation between electrodes. With this technique, the machining of conducting materials with submicrometre precision was achieved.

  16. Normalized Compression Distance of Multiples

    CERN Document Server

    Cohen, Andrew R

    2012-01-01

    Normalized compression distance (NCD) is a parameter-free similarity measure based on compression. The NCD between pairs of objects is not sufficient for all applications. We propose an NCD of finite multisets (multiples) of objacts that is metric and is better for many applications. Previously, attempts to obtain such an NCD failed. We use the theoretical notion of Kolmogorov complexity that for practical purposes is approximated from above by the length of the compressed version of the file involved, using a real-world compression program. We applied the new NCD for multiples to retinal progenitor cell questions that were earlier treated with the pairwise NCD. Here we get significantly better results. We also applied the NCD for multiples to synthetic time sequence data. The preliminary results are as good as nearest neighbor Euclidean classifier.

  17. Elasticity of Long Distance Travelling

    DEFF Research Database (Denmark)

    Knudsen, Mette Aagaard

    2011-01-01

    With data from the Danish expenditure survey for 12 years 1996 through 2007, this study analyses household expenditures for long distance travelling. Household expenditures are examined at two levels of aggregation having the general expenditures on transportation and leisure relative to five other...... aggregated commodities at the highest level, and the specific expenditures on plane tickets and travel packages at the lowest level. The Almost Ideal Demand System is applied to determine the relationship between expenditures on transportation and leisure and all other purchased non-durables within...... packages has higher income elasticity of demand than plane tickets but also higher than transportation and leisure in general. The findings within price sensitiveness are not as sufficient estimated, but the model results indicate that travel packages is far more price elastic than plane tickets which...

  18. Rough Way for Academics: Distance Education

    Science.gov (United States)

    Gursul, Fatih

    2010-01-01

    This study aims to compare the academics' perceptions about face to face and distance education, beside finding out the contributions of distance education to them, difficulties they experience in synchronous and asynchronous distance education environments and suggestions for possible solutions of the existing problems. The sample consists of 52…

  19. Global continuation for distance geometry problems

    Energy Technology Data Exchange (ETDEWEB)

    More, J.J.; Wu, Zhijun

    1995-03-01

    Distance geometry problems arise in the interpretation of NMR data and in the determination of protein structure. The authors formulate the distance geometry problem as a global minimization problem with special structure, and show the global smoothing techniques and a continuation approach for global optimization can be used to determine solutions of distance geometry problems with a nearly 100% probability of success.

  20. Analysing designed experiments in distance sampling

    Science.gov (United States)

    Stephen T. Buckland; Robin E. Russell; Brett G. Dickson; Victoria A. Saab; Donal N. Gorman; William M. Block

    2009-01-01

    Distance sampling is a survey technique for estimating the abundance or density of wild animal populations. Detection probabilities of animals inherently differ by species, age class, habitats, or sex. By incorporating the change in an observer's ability to detect a particular class of animals as a function of distance, distance sampling leads to density estimates...

  1. Pattern recognition of quantum information based on pattern-distance

    Institute of Scientific and Technical Information of China (English)

    Dong Daoyi; Chen Zonghai; Jiang Shengxiang

    2005-01-01

    Looking upon every encoding state of quantum information systems as a quantum information pattern, A kind of pattern-distance between different patterns as a measurement of comparability of quantum information patterns is defined, and two kinds of recognition algorithms based on pattern-distance for quantum information are proposed. They can respectively recognize quantum information with known objective pattern and unknown objective pattern. In the two algorithms, the phases and occurrence probabilities of different eigenpatterns of quantum information are sufficiently considered. Two examples demonstrate the feasibility and effectiveness of the two recognition methods. These algorithms point out a new and important path for applications of quantum information and pattern recognition.

  2. On the Total Variation Distance of Semi-Markov Chains

    DEFF Research Database (Denmark)

    Bacci, Giorgio; Bacci, Giovanni; Larsen, Kim Guldstrand

    2015-01-01

    linear real-time specifications. Specifically, we prove that the total variation between two SMCs coincides with the maximal difference w.r.t. the likelihood of satisfying arbitrary MTL formulas or omega-languages recognized by timed automata. Computing this distance (i.e., solving its threshold problem......Semi-Markov chains (SMCs) are continuous-time probabilistic transition systems where the residence time on states is governed by generic distributions on the positive real line. This paper shows the tight relation between the total variation distance on SMCs and their model checking problem over...

  3. From language identification to language distance

    Science.gov (United States)

    Gamallo, Pablo; Pichel, José Ramom; Alegria, Iñaki

    2017-10-01

    In this paper, we define two quantitative distances to measure how far apart two languages are. The distance measure that we have identified as more accurate is based on the perplexity of n-gram models extracted from text corpora. An experiment to compare forty-four European languages has been performed. For this purpose, we computed the distances for all the possible language pairs and built a network whose nodes are languages and edges are distances. The network we have built on the basis of linguistic distances represents the current map of similarities and divergences among the main languages of Europe.

  4. Kinematic Distance of Galactic Planetary Nebulae

    CERN Document Server

    Yang, A Y; Zhu, H; Leahy, D A; Wu, D

    2016-01-01

    We construct \\HI~absorption spectra for 18 planetary nebulae (PNe) and their background sources using the data from the International Galactic Plane Survey. We estimate the kinematic distances of these PNe, among which 15 objects' kinematic distances are obtained for the first time. The distance uncertainties of 13 PNe range from 10% to 50%, which is a significant improvement with uncertainties of a factor two or three smaller than most of previous distance measurements. We confirm that PN G030.2-00.1 is not a PN because of its large distance found here.

  5. ICT USAGE BY DISTANCE LEARNERS IN INDIA

    Directory of Open Access Journals (Sweden)

    Ashish Kumar AWADHIYA

    2014-07-01

    Full Text Available Open Universities across the world are embracing ICT based teaching and learning process to disseminate quality education to their learners spread across the globe. In India availability and access of ICT and learner characteristics are uneven and vary from state to state. Hence it is important to establish the facts about ICT access among learners, their ICT usage patterns and their readiness to use ICT for educational purpose. In view of this, a study was conducted with the objective to find out the access level of ICT among distance learners. The analysis indicates that maximum learners have desktop/laptops and most of them are accessing internet very frequently from their home. The analysis also indicates that maximum respondents are browsing social networking sites followed by educational and e-mail service providing websites. Findings suggest that there is a need to generate ICT based tutorials complemented with social networking tools and mobile applications. Study also shows that learners are equipped with mobile phones and they are browsing internet through it and also availing support services offered by the university. Hence possibility of integrating mobile phone services may be used for providing learner support services and content delivery.

  6. Learner characteristics involved in distance learning

    Energy Technology Data Exchange (ETDEWEB)

    Cernicek, A.T.; Hahn, H.A.

    1991-01-01

    Distance learning represents a strategy for leveraging resources to solve educational and training needs. Although many distance learning programs have been developed, lessons learned regarding differences between distance learning and traditional education with respect to learner characteristics have not been well documented. Therefore, we conducted a survey of 20 distance learning professionals. The questionnaire was distributed to experts attending the second Distance Learning Conference sponsored by Los Alamos National Laboratory. This survey not only acquired demographic information from each of the respondents but also identified important distance learning student characteristics. Significant distance learner characteristics, which were revealed statistically and which influence the effectiveness of distance learning, include the following: reading level, student autonomy, and self-motivation. Distance learning cannot become a more useful and effective method of instruction without identifying and recognizing learner characteristics. It will be important to consider these characteristics when designing all distance learning courses. This paper will report specific survey findings and their implications for developing distance learning courses. 9 refs., 6 tabs.

  7. Critical Points in Distance Learning System

    Directory of Open Access Journals (Sweden)

    Airina Savickaitė

    2013-08-01

    Full Text Available Purpose – This article presents the results of distance learning system analysis, i.e. the critical elements of the distance learning system. The critical points of distance learning are a part of distance education online environment interactivity/community process model. The most important is the fact that the critical point is associated with distance learning participants. Design/methodology/approach – Comparative review of articles and analysis of distance learning module. Findings – A modern man is a lifelong learner and distance learning is a way to be a modern person. The focus on a learner and feedback is the most important thing of learning distance system. Also, attention should be paid to the lecture-appropriate knowledge and ability to convey information. Distance system adaptation is the way to improve the learner’s learning outcomes. Research limitations/implications – Different learning disciplines and learning methods may have different critical points. Practical implications – The information of analysis could be important for both lecturers and students, who studies distance education systems. There are familiar critical points which may deteriorate the quality of learning. Originality/value – The study sought to develop remote systems for applications in order to improve the quality of knowledge. Keywords: distance learning, process model, critical points. Research type: review of literature and general overview.

  8. Distance Education at Silesian University of Technology

    Directory of Open Access Journals (Sweden)

    Piotr Klosowski

    2008-12-01

    Full Text Available This paper presents Distance Learning Platform used by Silesian University of Technology. Distance Learning Platform is based on modular object-oriented dynamic learning environment, represents LMS (Learning Management Systems technology, a software package designed to help educators create quality online courses. Currently on Distance Learning Platform at Silesian University of Technology are available over 520 online courses created for students of twelve University's faculties. Number of Distance Learning Platform users exceeds 12000. Distance Learning Platform works as typically asynchronous e-learning service, but in the future more synchronous e-learning services will be added. Distance Learning Platform has great potential to create a successful elearning experience by providing a plethora of excellent tools that can be used to enhance conventional classroom instruction, in hybrid courses, or any distance learning arrangements.

  9. Distance Education at Silesian University of Technology

    Directory of Open Access Journals (Sweden)

    Piotr Klosowski

    2008-12-01

    Full Text Available This paper presents Distance Learning Platform used by Silesian University of Technology. Distance Learning Platform is based on modular object-oriented dynamic learning environment, represents LMS (Learning Management Systems technology, a software package designed to help educators create quality online courses. Currently on Distance Learning Platform at Silesian University of Technology are available over 520 online courses created for students of twelve University's faculties. Number of Distance Learning Platform users exceeds 12000. Distance Learning Platform works as typically asynchronous e-learning service, but in the future more synchronous e-learning services will be added. Distance Learning Platform has great potential to create a successful elearning experience by providing a plethora of excellent tools that can be used to enhance conventional classroom instruction, in hybrid courses, or any distance learning arrangements.

  10. Modeling of Car-Following Required Safe Distance Based on Molecular Dynamics

    OpenAIRE

    Dayi Qu; Xiufeng Chen; Wansan Yang; Xiaohua Bian

    2014-01-01

    In car-following procedure, some distances are reserved between the vehicles, through which drivers can avoid collisions with vehicles before and after them in the same lane and keep a reasonable clearance with lateral vehicles. This paper investigates characters of vehicle operating safety in car following state based on required safe distance. To tackle this problem, we probe into required safe distance and car-following model using molecular dynamics, covering longitudinal and lateral safe...

  11. Open and Distance Learning Today. Routledge Studies in Distance Education Series.

    Science.gov (United States)

    Lockwood, Fred, Ed.

    This book contains the following papers on open and distance learning today: "Preface" (Daniel); "Big Bang Theory in Distance Education" (Hawkridge); "Practical Agenda for Theorists of Distance Education" (Perraton); "Trends, Directions and Needs: A View from Developing Countries" (Koul); "American Distance Education" (Moore); "Creating the…

  12. Long-Distance Free Fall

    Science.gov (United States)

    Gallant, Joseph

    1999-04-01

    One of the goals of physics education is to instill a sense of wonder in our students. We hope our natural curiosity will rub off on them and that they will apply the critical thinking skills we teach them to other aspects of their lives outside the classroom. As an example of this, consider the situation described in Milton's epic poem ``Paradise Lost''. Milton wrote that when the devil was cast out of heaven, he fell for nine days before landing in hell. In Milton's universe, hell is a separate place from Earth, but many people place hell at the center of the Earth. Based on these ideas, we can apply Newton's laws of motion to calculate the distance from heaven to Earth. This exercise is an example of the kind of intellectual exercise a physicist (or a physics student) might carry out when confronted with such information. We apply the basic principles of physics to a situation described in work of literature while making no attempt to validate or refute any philosophy, theology or ideology.

  13. Giant Sparks at Cosmological Distances?

    CERN Document Server

    Kulkarni, S R; Neill, J D; Zheng, Z; Juric, M

    2014-01-01

    [Abridged] Millisecond duration bright radio pulses in the 1.4-GHz band and with inferred dispersion measures (DM) well in excess of Galactic values have been reported by Lorimer et al. and Thornton et al.. The all-sky rate of these events is large, ~10^4 per day above ~1 Jy. To add to the mystery there now exists "Perytons'' -- also pulsed and dispersed sources but most certainly of local (artificial or atmospheric) origin. The suggested models now range from sources originating in the Earth's atmosphere, in stellar coronae, in other galaxies and at even cosmological distances. Using a series of physically motivated assumptions combined with the observed properties of these bursts, we explore possible constraints on sites or processes that can account for such high DMs. In our analysis, we focus on the first such reported event by Lorimer et al.: a 30 Jy, 5-ms duration burst with a dispersion measure of 375 cm^-3 pc and exhibiting a steep frequency-dependent pulse width (hereafter dubbed as the Sparker). Ass...

  14. The redshift-distance relation.

    Science.gov (United States)

    Segal, I E

    1993-06-01

    Key predictions of the Hubble law are inconsistent with direct observations on equitable complete samples of extragalactic sources in the optical, infrared, and x-ray wave bands-e.g., the predicted dispersion in apparent magnitude is persistently greatly in excess of its observed value, precluding an explanation via hypothetical perturbations or irregularities. In contrast, the predictions of the Lundmark (homogeneous quadratic) law are consistent with the observations. The Lundmark law moreover predicts the deviations between Hubble law predictions and observation with statistical consistency, while the Hubble law provides no explanation for the close fit of the Lundmark law. The flux-redshift law F [symbol, see text] (1 + z)/z appears consistent with observations on equitable complete samples in the entire observed redshift range, when due account is taken of flux limits by an optimal statistical method. Under the theoretical assumption that space is a fixed sphere, as in the Einstein universe, this law implies the redshift-distance relation z = tan2(r/2R), where R is the radius of the spherical space. This relation coincides with the prediction of chronometric cosmology, which estimates R as 160 +/- 40 Mpc (1 parsec = 3.09 x 10(16) m) from the proper motion to redshift relation of superluminal sources. Tangential aspects, including statistical methodology, fundamental physical theory, bright cluster galaxy samples, and proposed luminosity evolution, are briefly considered.

  15. THE GOULD'S BELT DISTANCE SURVEY

    Directory of Open Access Journals (Sweden)

    L. Loinard

    2011-01-01

    Full Text Available Observaciones que utilizan la interferometría de muy larga línea de base (VLBI por sus siglas en ingl´es pueden proveer la posición de radiofuentes compactas con una precisión del orden de 50 micro-segundos de arco. Esto es suficiente para medir la paralaje trigonométrica y los movimientos propios de cualquier objeto localizado hasta 500 pc del Sol con una precisión mejor que unos porcientos. Por ser magnéticamente activas, las estrellas jóvenes a menudo emiten emisión radio compacta detectable usando técnicas VLBI. Aquí, mostraremos cómo observaciones VLBI ya han restringido la distancia a las regiones de formación estelar cercanas más frecuentemente estudiadas (Tauro, Ofiuco, Orión, etc. y han empezado a revelar su estructura y su cinemática interna. Luego, describiremos un gran proyecto (llamado The Gould's Belt Distance Survey diseñado para proveer una vista detallada de la formación estelar en la vecindad Solar, usando observaciones VLBI.

  16. Distance-weighted city growth.

    Science.gov (United States)

    Rybski, Diego; García Cantú Ros, Anselmo; Kropp, Jürgen P

    2013-04-01

    Urban agglomerations exhibit complex emergent features of which Zipf's law, i.e., a power-law size distribution, and fractality may be regarded as the most prominent ones. We propose a simplistic model for the generation of citylike structures which is solely based on the assumption that growth is more likely to take place close to inhabited space. The model involves one parameter which is an exponent determining how strongly the attraction decays with the distance. In addition, the model is run iteratively so that existing clusters can grow (together) and new ones can emerge. The model is capable of reproducing the size distribution and the fractality of the boundary of the largest cluster. Although the power-law distribution depends on both, the imposed exponent and the iteration, the fractality seems to be independent of the former and only depends on the latter. Analyzing land-cover data, we estimate the parameter-value γ≈2.5 for Paris and its surroundings.

  17. Distance between Quantum States and Gauge-Gravity Duality

    Science.gov (United States)

    Miyaji, Masamichi; Numasawa, Tokiro; Shiba, Noburo; Takayanagi, Tadashi; Watanabe, Kento

    2015-12-01

    We study a quantum information metric (or fidelity susceptibility) in conformal field theories with respect to a small perturbation by a primary operator. We argue that its gravity dual is approximately given by a volume of maximal time slice in an anti-de Sitter spacetime when the perturbation is exactly marginal. We confirm our claim in several examples.

  18. Avaliando as práticas de educação corporativa à distância por meio do modelo de Kirkpatrick: um estudo de caso numa empresa do ramo de energia no estado do Paraná (Evaluating the distance corporate education practices by using Kirkpatrick's model: a case study in an energy company in the state of Paraná

    Directory of Open Access Journals (Sweden)

    Mayara Cristina Ghedini Silva

    2010-01-01

    Full Text Available Resumo: As organizações adotam estratégias complexas para desenvolver a aprendizagem dentro do contexto organizacional. O presente artigo busca avaliar as práticas de Educação Corporativa à Distância por meio do modelo de Kirkpatrick: um estudo de caso numa empresa do ramo de energia no estado do Paraná. Como referencial teórico foram abordados os conceitos de Educação Corporativa, de Educação à Distância, e as formas de avaliação de programas de qualificação à distância. A metodologia utilizada foi apoiada no estudo de caso e os instrumentos empregados para coletas dos dados foram as entrevistas, questionários e a observação direta. O estudo foi efetuado tendo por base o modelo de análise de Kirkpatrick, que define os níveis de avaliação: reação, aprendizado, comportamento (aplicação e resultado. Os resultados demonstraram que a atividade desenvolvida sensibilizou os colaboradores quanto à continuação da qualificação via EaD, o método de avaliação adotado mostra as impressões dos participantes. Com os resultados da avaliação, torna-se possível efetuar ações corretivas nas qualificações disponibilizadas pela organização, assegurando o êxito do processo de aprendizagem. Abstract: Organizations adopt complex strategies to develop learning in the organizational context. The present paper aims at evaluating the Distance Corporate Education via Kirkpatrick’s model: a case study in an energy company in the state of Parana. As theoretical reference, the Corporate Education concepts were approached as well as the evaluation methods of the Distance Education programs. The case study served as basis to the chosen methodology, and interviews, questionnaires and direct observation were used to collect data. The study was based on Kirkpatrick’s model of analysis, which defines the levels of evaluation: reaction, learning, behavior (use and results. The results showed that the developed activity made the

  19. Robust quantum dialogue based on the entanglement swapping between any two logical Bell states and the shared auxiliary logical Bell state

    Science.gov (United States)

    Ye, Tian-Yu

    2015-04-01

    In this paper, using the quantum entanglement swapping technologies under the collective-dephasing noise and the collective-rotation noise, two robust quantum dialogue protocols are proposed, respectively. The logical Bell states are used as the traveling states to combat the collective noise. The auxiliary logical Bell state is shared privately between two participants through the manner of direct transmission first. After encoded with the receiver's secret messages, it swaps entanglement with its adjacent logical Bell state. In this way, the information leakage problem is avoided. Moreover, Eve's active attacks can be detected with the help of decoy photon technology. For decoding, the Bell state measurements rather than the four-qubit joint measurements are needed.

  20. Consensus of Multiagent Systems With Distance-Dependent Communication Networks.

    Science.gov (United States)

    Jing, Gangshan; Zheng, Yuanshi; Wang, Long

    2016-08-29

    In this paper, we study the consensus problem of discrete-time and continuous-time multiagent systems with distance-dependent communication networks, respectively. The communication weight between any two agents is assumed to be a nonincreasing function of their distance. First, we consider the networks with fixed connectivity. In this case, the interaction between adjacent agents always exists but the influence could possibly become negligible if the distance is long enough. We show that consensus can be reached under arbitrary initial states if the decay rate of the communication weight is less than a given bound. Second, we study the networks with distance-dependent connectivity. It is assumed that any two agents interact with each other if and only if their distance does not exceed a fixed range. With the validity of some conditions related to the property of the initial communication graph, we prove that consensus can be achieved asymptotically. Third, we present some applications of the main results to opinion consensus problems and formation control problems. Finally, several simulation examples are presented to illustrate the effectiveness of the theoretical findings.

  1. Robotic laboratory for distance education

    Science.gov (United States)

    Luciano, Sarah C.; Kost, Alan R.

    2016-09-01

    This project involves the construction of a remote-controlled laboratory experiment that can be accessed by online students. The project addresses a need to provide a laboratory experience for students who are taking online courses to be able to provide an in-class experience. The chosen task for the remote user is an optical engineering experiment, specifically aligning a spatial filter. We instrument the physical laboratory set up in Tucson, AZ at the University of Arizona. The hardware in the spatial filter experiment is augmented by motors and cameras to allow the user to remotely control the hardware. The user interacts with a software on their computer, which communicates with a server via Internet connection to the host computer in the Optics Laboratory at the University of Arizona. Our final overall system is comprised of several subsystems. These are the optical experiment set-up, which is a spatial filter experiment; the mechanical subsystem, which interfaces the motors with the micrometers to move the optical hardware; the electrical subsystem, which allows for the electrical communications from the remote computer to the host computer to the hardware; and finally the software subsystem, which is the means by which messages are communicated throughout the system. The goal of the project is to convey as much of an in-lab experience as possible by allowing the user to directly manipulate hardware and receive visual feedback in real-time. Thus, the remote user is able to learn important concepts from this particular experiment and is able to connect theory to the physical world by actually seeing the outcome of a procedure. The latter is a learning experience that is often lost with distance learning and is one that this project hopes to provide.

  2. Epidemic spread over networks with agent awareness and social distancing

    KAUST Repository

    Paarporn, Keith

    2016-04-20

    We study an SIS epidemic model over an arbitrary connected network topology when the agents receive personalized information about the current epidemic state. The agents utilize their available information to either reduce interactions with their neighbors (social distancing) when they believe the epidemic is currently prevalent or resume normal interactions when they believe there is low risk of becoming infected. The information is a weighted combination of three sources: 1) the average states of nodes in contact neighborhoods 2) the average states of nodes in an information network 3) a global broadcast of the average epidemic state of the network. A 2n-state Markov Chain is first considered to model the disease dynamics with awareness, from which a mean-field discrete-time n-state dynamical system is derived, where each state corresponds to an agent\\'s probability of being infected. The nonlinear model is a lower bound of its linearized version about the origin. Hence, global stability of the origin (the diseasefree equilibrium) in the linear model implies global stability in the nonlinear model. When the origin is not stable, we show the existence of a nontrivial fixed point in the awareness model, which obeys a strict partial order in relation to the nontrivial fixed point of the dynamics without distancing. In simulations, we define two performance metrics to understand the effectiveness agent awareness has in reducing the spread of an epidemic. © 2015 IEEE.

  3. The role of implicit and explicit feedback in learning and the implications for distance education techniques

    NARCIS (Netherlands)

    Helden, J. van der; Bekkering, H.

    2014-01-01

    In this chapter, the authors review the cognitive scientific state-of-the-art relevant for Distance Education (DE) followed by an overview of how different aspects of Distance Education relate to such cognitive mechanisms. The goal is to list and categorize the cognitive advantages and disadvantages

  4. Investigating Students' Perspectives of Foreign Language Distance Education Curriculum According to Some Variables

    Science.gov (United States)

    Orhan, Ali; Ay, Sule Çeviker

    2017-01-01

    This study was carried out to investigate the students' satisfaction levels of foreign language distance education curriculum in a state university according to some variables. In the study, it was aimed to answer these questions: "What are the students' opinions about the distance education curriculum of Foreign Language I course and do…

  5. Leadership in Distance Education: Qualities and Qualifications Sought by Higher Education Institutions

    Science.gov (United States)

    Nworie, John; Haughton, Noela; Oprandi, Stephanie

    2012-01-01

    This article presents the results of an investigation into the qualities and qualifications sought in distance education leaders by institutions of higher education in the United States. The researchers examined 191 distance education leadership position announcements posted by online sources between 1997 and 2010. Content analysis of these…

  6. Cross-Sectional Evaluation of Distance Education Students' Learning Styles and Critical Thinking Dispositions in Turkey

    Science.gov (United States)

    Yüksel, Ismail; Türkses, Ercüment

    2015-01-01

    This study aims to examine distance education students' learning styles and critical thinking dispositions. This cross sectional survey was conducted on 114 Turkish distance education students from various departments in a state university. The data of the study were collected through Grasha-Riechmann Student Learning Style Scale (GRSLSS) and…

  7. Distance Learning in Indian Country: Becoming the Spider on the Web.

    Science.gov (United States)

    Sanchez, John; Stuckey, Mary E.; Morris, Richard

    1998-01-01

    Examines potential uses of distance learning for maintaining and sustaining American-Indian tribal communities within the United States while allowing access to the information and skills needed for employment in the dominant society. Examines distance education in general, traditional education in tribal contexts, tribal uses of…

  8. Monetizing French Distance Education: A Field Enquiry on Higher Education Value(s)

    Science.gov (United States)

    Olivier, Marty

    2014-01-01

    A field enquiry in French distance education allows us to analyze the evolution of a specific institution towards new public management: Parallel to a trend of free courseware and open education, there is a paradoxical reality of distance education monetization. Whereas history shows how traditional French education is a state controlled public…

  9. Cross-Sectional Evaluation of Distance Education Students' Learning Styles and Critical Thinking Dispositions in Turkey

    Science.gov (United States)

    Yüksel, Ismail; Türkses, Ercüment

    2015-01-01

    This study aims to examine distance education students' learning styles and critical thinking dispositions. This cross sectional survey was conducted on 114 Turkish distance education students from various departments in a state university. The data of the study were collected through Grasha-Riechmann Student Learning Style Scale (GRSLSS) and…

  10. Distance and Cable Length Measurement System

    Directory of Open Access Journals (Sweden)

    Jonay Toledo

    2009-12-01

    Full Text Available A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement.

  11. Distance and Cable Length Measurement System

    Science.gov (United States)

    Hernández, Sergio Elias; Acosta, Leopoldo; Toledo, Jonay

    2009-01-01

    A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement. PMID:22303169

  12. The Distance to the Draco Cloud

    CERN Document Server

    Gladders, M D; Burns, C R; Attard, A; Casey, M P; Hamilton, D; Mallén-Ornelas, G; Karr, J L; Poirier, S M; Sawicki, M; Barrientos, L F; Mochnacki, S W; Gladders, Michael D.; Burns, Christopher R.; Hamilton, Devon; Mallén-Ornelas, Gabriela; Poirier, Sara M.; Sawicki, Marcin; Mochnacki, Stefan W.

    1998-01-01

    The understanding of the nature of intermediate and high velocity gas in the Milky Way is hampered by a paucity of distance estimates to individual clouds. A project has been started at the David Dunlap Observatory to address this lack of distance measures by observing early-type stars along the line of sight towards these clouds and searching for sodium doublet absorption at the clouds' systemic velocities. Distances to foreground stars (no absorption) and background stars (with absorption) are estimated from spectroscopic parallax, and thus the distance to the bracketed cloud is estimated. In this Letter, we present the first result from this ongoing project, a measurement of the distance to the Draco Cloud, which is the most studied of the intermediate velocity clouds. The result presented here is the first distance bracket which tightly constrains the position of the Draco Cloud. We briefly describe our target selection and observing methodology, and then demonstrate absorption at the velocity of the Drac...

  13. Long distance signaling using axionlike particles

    Science.gov (United States)

    Stancil, Daniel D.

    2007-12-01

    The possible existence of axionlike particles could lead to a new type of long-distance communication. In this work, basic antenna concepts are defined and a Friis-like equation is derived to facilitate long-distance link calculations. An example calculation is presented showing that communication over distances of 1000 km or more may be possible for ma5×10-8GeV-1.

  14. Inverse Distance Weighted Interpolation Involving Position Shading

    OpenAIRE

    Li, Zhengquan; WU Yaoxiang

    2015-01-01

    Considering the shortcomings of inverse distance weighted (IDW) interpolation in practical applications, this study improved the IDW algorithm and put forward a new spatial interpolation method that named as adjusted inverse distance weighted (AIDW). In interpolating process, the AIDW is capable of taking into account the comprehensive influence of distance and position of sample point to interpolation point, by adding a coefficient (K) into the normal IDW formula. The coefficient (K) is used...

  15. Fast Exact Euclidean Distance (FEED): A New Class of Adaptable Distance Transforms.

    Science.gov (United States)

    Schouten, Theo E; van den Broek, Egon L

    2014-11-01

    A new unique class of foldable distance transforms of digital images (DT) is introduced, baptized: Fast exact euclidean distance (FEED) transforms. FEED class algorithms calculate the DT starting-directly from the definition or rather its inverse. The principle of FEED class algorithms is introduced, followed by strategies for their efficient implementation. It is shown that FEED class algorithms unite properties of ordered propagation, raster scanning, and independent scanning DT. Moreover, FEED class algorithms shown to have a unique property: they can be tailored to the images under investigation. Benchmarks are conducted on both the Fabbri et al. data set and on a newly developed data set. Three baseline, three approximate, and three state-of-the-art DT algorithms were included, in addition to two implementations of FEED class algorithms. It illustrates that FEED class algorithms i) provide truly exact Euclidean DT; ii) do no suffer from disconnected Voronoi tiles, which is a unique feature for non-parallel but fast DT; iii) outperform any other approximate and exact Euclidean DT with its time complexity O(N), even after their optimization; and iv) are unequaled in that they can be adapted to the characteristics of the image class at hand.

  16. Sublinear distance labeling for sparse graphs

    DEFF Research Database (Denmark)

    Alstrup, Stephen; Dahlgaard, Søren; Knudsen, Mathias Bæk Tejs;

    2015-01-01

    between pairs of nodes that are at distance at least $D$ from each other. In this paper we consider distance labeling schemes for the classical case of unweighted and undirected graphs. We present the first distance labeling scheme of size $o(n)$ for sparse graphs (and hence bounded degree graphs......). This addresses an open problem by Gavoille et. al. [J. Algo. 2004], hereby separating the complexity from general graphs which require $\\Omega(n)$ size Moon [Proc. of Glasgow Math. Association 1965]. As an intermediate result we give a $O(\\frac{n}{D}\\log^2 D)$ $D$-preserving distance labeling scheme, improving...

  17. A Cognitively Grounded Measure of Pronunciation Distance

    Science.gov (United States)

    Wieling, Martijn; Nerbonne, John; Bloem, Jelke; Gooskens, Charlotte; Heeringa, Wilbert; Baayen, R. Harald

    2014-01-01

    In this study we develop pronunciation distances based on naive discriminative learning (NDL). Measures of pronunciation distance are used in several subfields of linguistics, including psycholinguistics, dialectology and typology. In contrast to the commonly used Levenshtein algorithm, NDL is grounded in cognitive theory of competitive reinforcement learning and is able to generate asymmetrical pronunciation distances. In a first study, we validated the NDL-based pronunciation distances by comparing them to a large set of native-likeness ratings given by native American English speakers when presented with accented English speech. In a second study, the NDL-based pronunciation distances were validated on the basis of perceptual dialect distances of Norwegian speakers. Results indicated that the NDL-based pronunciation distances matched perceptual distances reasonably well with correlations ranging between 0.7 and 0.8. While the correlations were comparable to those obtained using the Levenshtein distance, the NDL-based approach is more flexible as it is also able to incorporate acoustic information other than sound segments. PMID:24416119

  18. A cognitively grounded measure of pronunciation distance.

    Science.gov (United States)

    Wieling, Martijn; Nerbonne, John; Bloem, Jelke; Gooskens, Charlotte; Heeringa, Wilbert; Baayen, R Harald

    2014-01-01

    In this study we develop pronunciation distances based on naive discriminative learning (NDL). Measures of pronunciation distance are used in several subfields of linguistics, including psycholinguistics, dialectology and typology. In contrast to the commonly used Levenshtein algorithm, NDL is grounded in cognitive theory of competitive reinforcement learning and is able to generate asymmetrical pronunciation distances. In a first study, we validated the NDL-based pronunciation distances by comparing them to a large set of native-likeness ratings given by native American English speakers when presented with accented English speech. In a second study, the NDL-based pronunciation distances were validated on the basis of perceptual dialect distances of Norwegian speakers. Results indicated that the NDL-based pronunciation distances matched perceptual distances reasonably well with correlations ranging between 0.7 and 0.8. While the correlations were comparable to those obtained using the Levenshtein distance, the NDL-based approach is more flexible as it is also able to incorporate acoustic information other than sound segments.

  19. Maximum likelihood estimates of pairwise rearrangement distances.

    Science.gov (United States)

    Serdoz, Stuart; Egri-Nagy, Attila; Sumner, Jeremy; Holland, Barbara R; Jarvis, Peter D; Tanaka, Mark M; Francis, Andrew R

    2017-06-21

    Accurate estimation of evolutionary distances between taxa is important for many phylogenetic reconstruction methods. Distances can be estimated using a range of different evolutionary models, from single nucleotide polymorphisms to large-scale genome rearrangements. Corresponding corrections for genome rearrangement distances fall into 3 categories: Empirical computational studies, Bayesian/MCMC approaches, and combinatorial approaches. Here, we introduce a maximum likelihood estimator for the inversion distance between a pair of genomes, using a group-theoretic approach to modelling inversions introduced recently. This MLE functions as a corrected distance: in particular, we show that because of the way sequences of inversions interact with each other, it is quite possible for minimal distance and MLE distance to differently order the distances of two genomes from a third. The second aspect tackles the problem of accounting for the symmetries of circular arrangements. While, generally, a frame of reference is locked, and all computation made accordingly, this work incorporates the action of the dihedral group so that distance estimates are free from any a priori frame of reference. The philosophy of accounting for symmetries can be applied to any existing correction method, for which examples are offered. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. A cognitively grounded measure of pronunciation distance.

    Directory of Open Access Journals (Sweden)

    Martijn Wieling

    Full Text Available In this study we develop pronunciation distances based on naive discriminative learning (NDL. Measures of pronunciation distance are used in several subfields of linguistics, including psycholinguistics, dialectology and typology. In contrast to the commonly used Levenshtein algorithm, NDL is grounded in cognitive theory of competitive reinforcement learning and is able to generate asymmetrical pronunciation distances. In a first study, we validated the NDL-based pronunciation distances by comparing them to a large set of native-likeness ratings given by native American English speakers when presented with accented English speech. In a second study, the NDL-based pronunciation distances were validated on the basis of perceptual dialect distances of Norwegian speakers. Results indicated that the NDL-based pronunciation distances matched perceptual distances reasonably well with correlations ranging between 0.7 and 0.8. While the correlations were comparable to those obtained using the Levenshtein distance, the NDL-based approach is more flexible as it is also able to incorporate acoustic information other than sound segments.

  1. Distance and the urge of directness

    Directory of Open Access Journals (Sweden)

    Elżbieta Winiecka

    2009-01-01

    Full Text Available The article presents B. Leśmian as a poet involved in his self-imposed task of promoting a return to primeval nature, but, at the same time, somebody who is fully aware of the utopian character of thus formulated and adopted assumptions. The two contradictory approaches converge in a poetic figure of desire. This particular urge is treated as a model of the imagination of the poet, who creates his poetical world knowing that the ultimate aim is unattainable but constitutes the ideal of poetry and can only be a state of cognitive assurance and self-knowledge or, alternatively, a situation of ontological stability and fulfilment. However, to reach this utmost goal, either on the poetical plane or on the existentialist, epistemological and ontological plane, to fulfill the cherished desires, is not possible within the poetical world created by Leśmian. The raison d’etre of the self manifested by the protagonists of his poems as well as a justification of this poetry is the very striving towards the goal. The article shows the relevant dimensions of that desire as a metapoetical figure, anthropological and existentialist figures and epistemological and ontological figures. It further presents the opposition and the inner conflict within the modern views of the poet, who, consciously inscribes into his project its impracticability. The distance towards the current times and towards the idealistic assumptions of his own poetical programme constitutes the intrinsic originality of Leśmian’s poems.

  2. Non-monotonicity of trace distance under tensor products

    Energy Technology Data Exchange (ETDEWEB)

    Maziero, Jonas, E-mail: jonas.maziero@ufsm.br [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Departamento de Fisica

    2015-10-15

    The trace distance (TD) possesses several of the good properties required for a faithful distance measure in the quantum state space. Despite its importance and ubiquitous use in quantum information science, one of its questionable features, its possible non-monotonicity under taking tensor products of its arguments (NMuTP), has been hitherto unexplored. In this article, we advance analytical and numerical investigations of this issue considering different classes of states living in a discrete and finite dimensional Hilbert space. Our results reveal that although this property of TD does not show up for pure states and for some particular classes of mixed states, it is present in a non-negligible fraction of the regarded density operators. Hence, even though the percentage of quartets of states leading to the NMuTP drawback of TD and its strength decrease as the system's dimension grows, this property of TD must be taken into account before using it as a figure of merit for distinguishing mixed quantum states. (author)

  3. Modeling seed dispersal distances: implications for transgenic Pinus taeda.

    Science.gov (United States)

    Williams, Claire G; LaDeau, Shannon L; Oren, Ram; Katul, Gabriel G

    2006-02-01

    Predicting forest-tree seed dispersal across a landscape is useful for estimating gene flow from genetically engineered (GE) or transgenic trees. The question of biocontainment has yet to be resolved, although field-trial permits for transgenic forest trees are on the rise. Most current field trials in the United States occur in the Southeast where Pinus taeda L., an indigenous species, is the major timber commodity. Seed dispersal distances were simulated using a model where the major determinants were: (1) forest canopy height at seed release, (2) terminal velocity of the seeds, (3) absolute seed release, and (4) turbulent-flow statistics, all of which were measured or determined within a P. taeda plantation established from seeds collected from wild forest-tree stands at the Duke Forest near Durham, North Carolina, USA. In plantations aged 16 and 25 years our model results showed that most of the seeds fell within local-neighborhood dispersal distances, with estimates ranging from 0.05 to 0.14 km from the source. A fraction of seeds was uplifted above the forest canopy and moved via the long-distance dispersal (LDD) process as far as 11.9-33.7 km. Out of 10(5) seeds produced per hectare per year, roughly 440 seeds were predicted to be uplifted by vertical eddies above the forest canopy and transported via LDD. Of these, 70 seeds/ha traveled distances in excess of 1 km from the source, a distance too great to serve as a biocontainment zone. The probability of LDD occurrence of transgenic conifer seeds at distances exceeding 1 km approached 100%.

  4. Long distance atomic teleportation with as good success as desired

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Manoj K., E-mail: manoj.qit@gmail.com [Physics Department, University of Allahabad (India); Space Applications Centre, Indian Space Research Organization (ISRO), Ahmedabad (India); Prakash, Hari [Physics Department, University of Allahabad (India); Indian Institute of Information Technology, Allahabad (India)

    2015-09-15

    Long distance atomic teleportation (LDAT) is of prime importance in long distance quantum communication. Scheme proposed by Bose et al. (1999) in principle enables us to have LDAT using cavity decay. However it gives message state dependent fidelity and success rate. Here, using interaction of entangled coherent states with atom–cavity systems and a two-step measurement, we show how, LDAT can be achieved with unit fidelity and as good success as desired under ideal conditions. The scheme is unique in that, the first measurement predicts success or failure. If success is predicted then second measurement gives perfect teleportation. If failure is predicted the message-qubit remains conserved therefore a second attempt may be started. We found that even in presence of decoherence due to dissipation of energy our scheme gives message state independent success rate and almost perfect teleportation in single attempt with mean fidelity of teleportation equal to 0.9 at long distances. However if first attempt fails, unlike ideal case where message-qubit remains conserved with unit fidelity, in presence of decoherence the message-qubit remains conserved to some degree, therefore mean fidelity of teleportation can be increased beyond 0.9 by repeating the process.

  5. Modeling of Car-Following Required Safe Distance Based on Molecular Dynamics

    Directory of Open Access Journals (Sweden)

    Dayi Qu

    2014-01-01

    Full Text Available In car-following procedure, some distances are reserved between the vehicles, through which drivers can avoid collisions with vehicles before and after them in the same lane and keep a reasonable clearance with lateral vehicles. This paper investigates characters of vehicle operating safety in car following state based on required safe distance. To tackle this problem, we probe into required safe distance and car-following model using molecular dynamics, covering longitudinal and lateral safe distance. The model was developed and implemented to describe the relationship between longitudinal safe distance and lateral safe distance under the condition where the leader keeps uniform deceleration. The results obtained herein are deemed valuable for car-following theory and microscopic traffic simulation.

  6. National Wind Distance Learning Collaborative

    Energy Technology Data Exchange (ETDEWEB)

    Dr. James B. Beddow

    2013-03-29

    Executive Summary The energy development assumptions identified in the Department of Energy's position paper, 20% Wind Energy by 2030, projected an exploding demand for wind energy-related workforce development. These primary assumptions drove a secondary set of assumptions that early stage wind industry workforce development and training paradigms would need to undergo significant change if the workforce needs were to be met. The current training practice and culture within the wind industry is driven by a relatively small number of experts with deep field experience and knowledge. The current training methodology is dominated by face-to-face, classroom based, instructor present training. Given these assumptions and learning paradigms, the purpose of the National Wind Distance Learning Collaborative was to determine the feasibility of developing online learning strategies and products focused on training wind technicians. The initial project scope centered on (1) identifying resources that would be needed for development of subject matter and course design/delivery strategies for industry-based (non-academic) training, and (2) development of an appropriate Learning Management System (LMS). As the project unfolded, the initial scope was expanded to include development of learning products and the addition of an academic-based training partner. The core partners included two training entities, industry-based Airstreams Renewables and academic-based Lake Area Technical Institute. A third partner, Vision Video Interactive, Inc. provided technology-based learning platforms (hardware and software). The revised scope yielded an expanded set of results beyond the initial expectation. Eight learning modules were developed for the industry-based Electrical Safety course. These modules were subsequently redesigned and repurposed for test application in an academic setting. Software and hardware developments during the project's timeframe enabled redesign providing

  7. Research on Distance Education Development in China

    Science.gov (United States)

    Xin, Ding; Jian, Niu; Yanhui, Han

    2010-01-01

    Distance education is among the significant fields for the application of educational technology. Distance education in China has gone through three phases, namely: correspondence-based education, radio and TV-based education and online education. This paper was based on educational technology application, and the historical, dialectic and…

  8. Binding Principle for Long-Distance Anaphors.

    Science.gov (United States)

    Choi, Dong-Ik

    1997-01-01

    An analysis of long-distance anaphora, a binding phenomenon in which reflexives find their antecedents outside their local domain, is presented, using data from English, Chinese, Japanese, Korean, Russian, Icelandic, and Italian. It is found that no approach deals with long-distance anaphors exclusively and elegantly. The binding domain…

  9. Isolation by language and distance in Belgium.

    Science.gov (United States)

    Barrai, I; Rodriguez-Larralde, A; Manni, F; Ruggiero, V; Tartari, D; Scapoli, C

    2004-01-01

    The isonymy structure of trilingual Belgium was studied using the surname distributions for 1,118,004 private telephone users. The users were distributed in 77 Flemish, 76 French, and 3 German speaking towns, selected on a geographic basis to form an approximately regular grid over Belgium. Lasker's distance was found to be considerably higher between languages than within languages. For the whole of Belgium, irrespective of language, it was highly correlated with linear geographic distance, with r = 0.721+/-0.014, which is the highest correlation observed in European countries to date. Within Belgium and within languages, the correlation was highest among the Flemish (r = 0.878 +/- 0.007), and lowest among the French (r = 0.631+/-0.020). Isolation by distance in Belgium is the highest we have found in Europe, and as high as in Switzerland where the different languages are separated by geographical barriers. This is not the case in Belgium, so that the considerable isolating power of languages emerges clearly from the present analysis. From the comparison of Lasker's distance between (9.48) and within (8.16) languages, and from its regression over geographic distance (b = 0.01206), it was possible to establish a quantitative relationship between the isolating power of languages and that of geographic distance as (9.48-8.16)/0.01206 = 109 kilometres. This transformation of language distance into an equivalent geographic distance, given here for Belgium, can be applied to any similar geo-linguistic situation.

  10. Language Distance Learning for the Digital Generation

    Science.gov (United States)

    Duran-Cerda, Dolores

    2010-01-01

    The purpose of this article was to shed light on the potential of distance learning to overcome challenges in distance, space, time, and human and economic resources that limit access to language learning opportunities in cultural, literary, historical, geographical, and cross-cultural frames. Language and literature educators collectively have…

  11. Designing legible fonts for distance reading

    DEFF Research Database (Denmark)

    Beier, Sofie

    2016-01-01

    This chapter reviews existing knowledge on distance legibility of fonts, and finds that for optimal distance reading, letters and numbers benefit from relative wide shapes, open inner counters and a large x-height; fonts should further be widely spaced, and the weight should not be too heavy or t...

  12. Sensor Network Localization with Imprecise Distances

    NARCIS (Netherlands)

    Cao, M.; Morse, A.S.; Anderson, B.D.O.

    2006-01-01

    An approach to formulate geometric relations among distances between nodes as equality constraints is introduced in this paper to study the localization problem with imprecise distance information in sensor networks. These constraints can be further used to formulate optimization problems for distan

  13. A Survey on Distance Vector Routing Protocols

    CERN Document Server

    Tang, Linpeng

    2011-01-01

    In this paper we give a brief introduction to five different distance vector routing protocols (RIP, AODV, EIGRP, RIP-MTI and Babel) and give some of our thoughts on how to solve the count to infinity problem. Our focus is how distance vector routing protocols, based on limited information, can prevent routing loops and the count to infinity problem.

  14. Who Graduates from Irish Distance University Education?

    Science.gov (United States)

    Delaney, Lorraine

    2015-01-01

    This paper outlines results from an online survey of recent distance graduates. The study, based in Dublin City University (DCU) addresses a gap in the research on this cohort of graduates. Findings indicate that distance graduates are primarily from lower socio economic backgrounds, a group largely under-represented in full-time university…

  15. Distance Education for People with Visual Impairments

    Science.gov (United States)

    Liakou, Maria; Manousou, Evaggelia

    2015-01-01

    This paper studies the standards of higher Distance Education, focusing on the Hellenic Open University, for people who have visual impairments, so that it becomes fully accessible and thus helps reduce social exclusion. Specifically, it aims to study the operational context of Distance Education, the possibilities that modern technology provides…

  16. Audiences and Providers of Distance Education

    Science.gov (United States)

    Nazarinia Roy, R. Roudi; Schumm, Walter R.

    2011-01-01

    As noted by Moore (2007, xxiii), the fifth section of the second edition of the "Handbook of Distance Education" focused on "some of the main consumers and suppliers of distance education programs," including elementary and secondary education, community colleges, universities, the corporate sector, continuing professional…

  17. Investigating Distance Education Students' Study Skills

    Science.gov (United States)

    Poyraz, Cengiz

    2013-01-01

    Distance education, which is a planned way of teaching in which students and instructors are brought face to face in a classroom environment in several different ways by means of technology, has started to become widespread in many fields today. In distance education, students and instructors reside in different locations. Students can learn at…

  18. Applying Leadership Theories to Distance Education Leadership

    Science.gov (United States)

    Nworie, John

    2012-01-01

    The instructional delivery mode in distance education has been transitioning from the context of a physical classroom environment to a virtual learning environment or maintaining a hybrid of the two. However, most distance education programs in dual mode institutions are situated in traditional face-to-face instructional settings. Distance…

  19. Distance Education Report, 2011-2012

    Science.gov (United States)

    California Community Colleges, Chancellor's Office, 2013

    2013-01-01

    This is a report on distance education in the California Community College. This is the seventh report to the California Community Colleges Board of Governors (BOG) per BOG Standing Order 409 (b) "that evaluates the effectiveness of distance education and education technology system wide and provides analysis of data demographically (by age,…

  20. Three Generations of Distance Education Pedagogy

    Science.gov (United States)

    Anderson, Terry; Dron, Jon

    2011-01-01

    This paper defines and examines three generations of distance education pedagogy. Unlike earlier classifications of distance education based on the technology used, this analysis focuses on the pedagogy that defines the learning experiences encapsulated in the learning design. The three generations of cognitive-behaviourist, social constructivist,…