WorldWideScience

Sample records for quantum registers based

  1. Novel Quantum Encryption Algorithm Based on Multiqubit Quantum Shift Register and Hill Cipher

    International Nuclear Information System (INIS)

    Khalaf, Rifaat Zaidan; Abdullah, Alharith Abdulkareem

    2014-01-01

    Based on a quantum shift register, a novel quantum block cryptographic algorithm that can be used to encrypt classical messages is proposed. The message is encoded and decoded by using a code generated by the quantum shift register. The security of this algorithm is analysed in detail. It is shown that, in the quantum block cryptographic algorithm, two keys can be used. One of them is the classical key that is used in the Hill cipher algorithm where Alice and Bob use the authenticated Diffie Hellman key exchange algorithm using the concept of digital signature for the authentication of the two communicating parties and so eliminate the man-in-the-middle attack. The other key is generated by the quantum shift register and used for the coding of the encryption message, where Alice and Bob share the key by using the BB84 protocol. The novel algorithm can prevent a quantum attack strategy as well as a classical attack strategy. The problem of key management is discussed and circuits for the encryption and the decryption are suggested

  2. Quantum logic between remote quantum registers

    Science.gov (United States)

    Yao, N. Y.; Gong, Z.-X.; Laumann, C. R.; Bennett, S. D.; Duan, L.-M.; Lukin, M. D.; Jiang, L.; Gorshkov, A. V.

    2013-02-01

    We consider two approaches to dark-spin-mediated quantum computing in hybrid solid-state spin architectures. First, we review the notion of eigenmode-mediated unpolarized spin-chain state transfer and extend the analysis to various experimentally relevant imperfections: quenched disorder, dynamical decoherence, and uncompensated long-range coupling. In finite-length chains, the interplay between disorder-induced localization and decoherence yields a natural optimal channel fidelity, which we calculate. Long-range dipolar couplings induce a finite intrinsic lifetime for the mediating eigenmode; extensive numerical simulations of dipolar chains of lengths up to L=12 show remarkably high fidelity despite these decay processes. We further briefly consider the extension of the protocol to bosonic systems of coupled oscillators. Second, we introduce a quantum mirror based architecture for universal quantum computing that exploits all of the dark spins in the system as potential qubits. While this dramatically increases the number of qubits available, the composite operations required to manipulate dark-spin qubits significantly raise the error threshold for robust operation. Finally, we demonstrate that eigenmode-mediated state transfer can enable robust long-range logic between spatially separated nitrogen-vacancy registers in diamond; disorder-averaged numerics confirm that high-fidelity gates are achievable even in the presence of moderate disorder.

  3. Wavefunctions for topological quantum registers

    International Nuclear Information System (INIS)

    Ardonne, E.; Schoutens, K.

    2007-01-01

    We present explicit wavefunctions for quasi-hole excitations over a variety of non-abelian quantum Hall states: the Read-Rezayi states with k ≥ 3 clustering properties and a paired spin-singlet quantum Hall state. Quasi-holes over these states constitute a topological quantum register, which can be addressed by braiding quasi-holes. We obtain the braid properties by direct inspection of the quasi-hole wavefunctions. We establish that the braid properties for the paired spin-singlet state are those of 'Fibonacci anyons', and thus suitable for universal quantum computation. Our derivations in this paper rely on explicit computations in the parafermionic conformal field theories that underly these particular quantum Hall states

  4. Decoherence in large NMR quantum registers

    International Nuclear Information System (INIS)

    Krojanski, Hans Georg; Suter, Dieter

    2006-01-01

    Decoherence causes the decay of the quantum information that is stored in highly correlated states during quantum computation. It is thus a limiting factor for all implementations of a quantum computer. Because a scalable quantum computer with hundreds or thousands of qubits is not available yet, experimental data about decoherence rates was restricted to small quantum registers. With solid state nuclear magnetic resonance we create highly correlated multiqubit states that serve as a model quantum register and measure their decay. By measuring the decay as a function of the system size, we determined the scaling of the decoherence rate with the number of qubits. Using the same system, we also used decoupling techniques to reduce the coupling between system and environment and thereby the decoherence rate by more than an order of magnitude, independent of the system size. For the free decay as well as for the decoupled case, we found a relatively weak scaling with system size, which could be fitted to a power law ∝K p with an exponent p≅1/2. This raises the prospect for large-scale quantum computation

  5. A small trapped-ion quantum register

    International Nuclear Information System (INIS)

    Kielpinski, D

    2003-01-01

    We review experiments performed at the National Institute of Standards and Technology on entanglement, Bell's inequality and decoherence-free subspaces (DFSs) in a quantum register of trapped 9 Be + ions. The group of Dr David Wineland has demonstrated entanglement of up to four ions using the technique of Molmer and Sorensen. This method produces the state (|↓↓> + |↑↑>)/√2 for two ions and the state (|↓↓↓↓> + |↑↑↑↑>)/√2 for four ions. The entanglement was generated deterministically in each shot of the experiment. Measurements on the two-ion entangled state violate Bell's inequality at the 8σ level. Because of the high detector efficiency of the apparatus, this experiment closes the detector loophole for Bell's inequality measurements for the first time. This measurement is also the first violation of Bell's inequality by massive particles that does not implicitly assume results from quantum mechanics. The group also demonstrated measurement of an interferometric phase with precision better than the shot-noise limit using a two-ion entangled state. A large-scale version of this scheme could improve the signal-to-noise ratio of atomic clocks by orders of magnitude. Further experiments demonstrated reversible encoding of an arbitrary qubit, originally contained in one ion, into a DFS of two ions. The DFS-encoded qubit resists applied collective dephasing noise and retains coherence under ambient conditions 3.6 times longer than does an unencoded qubit. The encoding method, which uses single-ion gates and the two-ion entangling gate, demonstrates all the elements required for two-qubit universal quantum logic. Finally, we describe an architecture for a large-scale ion trap quantum computer. By performing logic gates on small numbers of ions trapped in separate regions of the array, we take advantage of existing techniques for manipulating small trapped-ion quantum registers while enabling massively parallel gate operation. Encoding the

  6. High-fidelity projective read-out of a solid-state spin quantum register.

    Science.gov (United States)

    Robledo, Lucio; Childress, Lilian; Bernien, Hannes; Hensen, Bas; Alkemade, Paul F A; Hanson, Ronald

    2011-09-21

    Initialization and read-out of coupled quantum systems are essential ingredients for the implementation of quantum algorithms. Single-shot read-out of the state of a multi-quantum-bit (multi-qubit) register would allow direct investigation of quantum correlations (entanglement), and would give access to further key resources such as quantum error correction and deterministic quantum teleportation. Although spins in solids are attractive candidates for scalable quantum information processing, their single-shot detection has been achieved only for isolated qubits. Here we demonstrate the preparation and measurement of a multi-spin quantum register in a low-temperature solid-state system by implementing resonant optical excitation techniques originally developed in atomic physics. We achieve high-fidelity read-out of the electronic spin associated with a single nitrogen-vacancy centre in diamond, and use this read-out to project up to three nearby nuclear spin qubits onto a well-defined state. Conversely, we can distinguish the state of the nuclear spins in a single shot by mapping it onto, and subsequently measuring, the electronic spin. Finally, we show compatibility with qubit control: we demonstrate initialization, coherent manipulation and single-shot read-out in a single experiment on a two-qubit register, using techniques suitable for extension to larger registers. These results pave the way for a test of Bell's inequalities on solid-state spins and the implementation of measurement-based quantum information protocols. © 2011 Macmillan Publishers Limited. All rights reserved

  7. Register-based studies of healthcare costs

    DEFF Research Database (Denmark)

    Kruse, Marie; Christiansen, Terkel

    2011-01-01

    Introduction: The aim of this paper is to provide an overview and a few examples of how national registers are used in analyses of healthcare costs in Denmark. Research topics: The paper focuses on health economic analyses based on register data. For the sake of simplicity, the studies are divided...... into three main categories: economic evaluations of healthcare interventions, cost-of-illness analyses, and other analyses such as assessments of healthcare productivity. Conclusion: We examined a number of studies using register-based data on healthcare costs. Use of register-based data renders...

  8. Universal shift register implementation using quantum dot cellular automata

    Directory of Open Access Journals (Sweden)

    Tamoghna Purkayastha

    2018-06-01

    Full Text Available Quantum-dot Cellular Automata (QCA demands to be a promising alternative of CMOS in ultra large scale circuit integration. Arithmetic and logic unit designs using QCA are of high research interest. A layout of four and eight bit universal shift register (USR has been proposed. Initially QCA layouts of D flip-flop with clear and 4 to 1 multiplexer are designed, which are extended to design 4 and 8-bit parallel in parallel out (PIPO shift register. Finally the PIPO is utilized to design 4-bit and 8-bit USR. By the comparative analysis it is observed that the proposed D Flip-flop achieved 40% clock delay improvement, whereas the modified layout of 4 to 1 multiplexer achieved 30% cell count reduction and 17% clock delay reduction from the previous works. This results in 31% reduction in cell count, 45% reduction in area and 55% reduction in clock cycle delay in 8 bit USR layout.

  9. Register-based research on twins

    DEFF Research Database (Denmark)

    Christensen, Kaare; Ohm Kyvik, Kirsten; Holm, Niels V

    2011-01-01

    Introduction: The Danish Twin Registry (DTR) has for more than 50 years been based on surveys and clinical investigations and over the two last decades also on register linkage. Currently these two approaches are merged within Statistics Denmark. Research topics: Here we report on three major...... groups of register-based research in the DTR that used the uniqueness of twinning. First, we focus on the ''long-term prognosis'' of being a twin compared with being a singleton and show that Danish twins have health trajectories in adulthood similar to singletons, which is a result of interest for twins...... illustrate how the co-twin control method in a register setting can be used to control for the effect of rearing environment and genetic factors in studies of the association between exposures and health. CONCLUSION: The spectrum of register-based twin studies is very wide and have changed in accordance...

  10. Register-based studies of cardiovascular disease

    DEFF Research Database (Denmark)

    Abildstrøm, Steen Z; Torp-Pedersen, Christian; Madsen, Mette

    2011-01-01

    Introduction: The use of the unique personal identification number in the Nordic database systems enables the researchers to link the registers at the individual level. The registers can be used for both defining specific patient populations and to identify later events during follow-up. This rev...... the hospitalisation rate and treatment of cardiovascular disease. The risk of unmeasured factors affecting the results calls for cautious interpretation of the results.......-up. This review gives three examples within cardiovascular epidemiology to illustrate the use of the national administrative registers available to all researchers upon request. Research topics: The hospitalisation rate of acute myocardial infarction (AMI) was expected to be increased and case-fatality rate......-based treatment increased significantly over time and adherence to treatment was high. Finally, use of specific nonsteroidal antiinflammatory drugs by healthy subjects was associated with a dose-dependent increase in cardiovascular risk. CONCLUSION: The nationwide registers have proven very useful in monitoring...

  11. Memory-built-in quantum cloning in a hybrid solid-state spin register

    Science.gov (United States)

    Wang, W.-B.; Zu, C.; He, L.; Zhang, W.-G.; Duan, L.-M.

    2015-07-01

    As a way to circumvent the quantum no-cloning theorem, approximate quantum cloning protocols have received wide attention with remarkable applications. Copying of quantum states to memory qubits provides an important strategy for eavesdropping in quantum cryptography. We report an experiment that realizes cloning of quantum states from an electron spin to a nuclear spin in a hybrid solid-state spin register with near-optimal fidelity. The nuclear spin provides an ideal memory qubit at room temperature, which stores the cloned quantum states for a millisecond under ambient conditions, exceeding the lifetime of the original quantum state carried by the electron spin by orders of magnitude. The realization of a cloning machine with built-in quantum memory provides a key step for application of quantum cloning in quantum information science.

  12. Register-based studies on migration, ethnicity, and health

    DEFF Research Database (Denmark)

    Norredam, Marie; Kastrup, Marianne; Helweg-Larsen, Karin

    2011-01-01

    INTRODUCTION: Researchers in Denmark have unique possibilities of register-based research in relation to migration, ethnicity, and health. This review article outlines how these opportunities have been used, so far, by presenting a series of examples. RESEARCH TOPICS: We selected six registers...... it discriminatory. Although, we do not register ethnicity in relation to use of health care in Denmark, our possibilities of linkage between population registers and registers on diseases and healthcare utilisation appear to render the same potentials....... to highlight the process of how migrant study populations have been established and studied in relation to different registers: The Danish Cancer Registry, the Danish Central Psychiatric Research Register, the Danish National Patient Register, the Danish National Health Service Register, the Danish Injury...

  13. Universal Verification Methodology Based Register Test Automation Flow.

    Science.gov (United States)

    Woo, Jae Hun; Cho, Yong Kwan; Park, Sun Kyu

    2016-05-01

    In today's SoC design, the number of registers has been increased along with complexity of hardware blocks. Register validation is a time-consuming and error-pron task. Therefore, we need an efficient way to perform verification with less effort in shorter time. In this work, we suggest register test automation flow based UVM (Universal Verification Methodology). UVM provides a standard methodology, called a register model, to facilitate stimulus generation and functional checking of registers. However, it is not easy for designers to create register models for their functional blocks or integrate models in test-bench environment because it requires knowledge of SystemVerilog and UVM libraries. For the creation of register models, many commercial tools support a register model generation from register specification described in IP-XACT, but it is time-consuming to describe register specification in IP-XACT format. For easy creation of register model, we propose spreadsheet-based register template which is translated to IP-XACT description, from which register models can be easily generated using commercial tools. On the other hand, we also automate all the steps involved integrating test-bench and generating test-cases, so that designers may use register model without detailed knowledge of UVM or SystemVerilog. This automation flow involves generating and connecting test-bench components (e.g., driver, checker, bus adaptor, etc.) and writing test sequence for each type of register test-case. With the proposed flow, designers can save considerable amount of time to verify functionality of registers.

  14. Catalog of 199 register-based definitions of chronic conditions

    DEFF Research Database (Denmark)

    Hvidberg, Michael F; Johnsen, Søren P; Glümer, Charlotte

    2016-01-01

    INTRODUCTION: The aim of the current study was to present and discuss a broad range of register-based definitions of chronic conditions for use in register research, as well as the challenges and pitfalls when defining chronic conditions by the use of registers. MATERIALS AND METHODS: The definit......INTRODUCTION: The aim of the current study was to present and discuss a broad range of register-based definitions of chronic conditions for use in register research, as well as the challenges and pitfalls when defining chronic conditions by the use of registers. MATERIALS AND METHODS......: The definitions were defined based on information from nationwide Danish public healthcare registers. Medical and epidemiological specialists identified and grouped relevant diagnosis codes that covered chronic conditions, using the International Classification System version 10 (ICD-10). Where relevant...... definitions were proposed based on record linkage between multiple registers, including registers of prescribed drugs and use of general practitioners' services. CONCLUSIONS THIS STUDY PROVIDED A CATALOG OF REGISTER-BASED DEFINITIONS FOR CHRONIC CONDITIONS FOR USE IN HEALTHCARE PLANNING AND RESEARCH, WHICH IS...

  15. Identifying victims of violence using register-based data

    DEFF Research Database (Denmark)

    Kruse, Marie; Sørensen, Jan; Brønnum-Hansen, Henrik

    2010-01-01

    AIMS: The aim of this study was twofold. Firstly we identified victims of violence in national registers and discussed strengths and weaknesses of this approach. Secondly we assessed the magnitude of violence and the characteristics of the victims using register-based data. METHODS: We used three...... nationwide registers to identify victims of violence: The National Patient Register, the Victim Statistics, and the Causes of Death Register. We merged these data and assessed the degree of overlap between data sources. We identified a reference population by selecting all individuals in Denmark over 15....... RESULTS: In 2006, 22,000 individuals were registered as having been exposed to violence. About 70% of these victims were men. Most victims were identified from emergency room contacts and police records, and few from the Causes of Death Register. There was some overlap between the two large data sources...

  16. Studies based on the Danish Adoption Register

    DEFF Research Database (Denmark)

    Petersen, Liselotte; Sørensen, Thorkild I A

    2011-01-01

    biological relatives to adoptees without schizophrenia. Clear trends in body mass index of biological relatives and the weight of adoptees were found in several settings. A genetic influence on smoking habits were found within a generation. A moderate genetic influence on the mortality rate has been found....... CONCLUSION: The Danish Adoption Register has contributed to the knowledge about environmental and genetic influence in various fields. Genetic influence on the risk of schizophrenia, body fatness, smoking habits, and on the mortality rate has been found........ RESEARCH TOPICS: To illustrate the adoption study approach in research, we present results achieved in schizophrenia, body fatness, smoking, and mortality. Significantly higher prevalence of schizophrenia and related conditions were found in biological relatives to adoptees with schizophrenia than among...

  17. Register-based statistics statistical methods for administrative data

    CERN Document Server

    Wallgren, Anders

    2014-01-01

    This book provides a comprehensive and up to date treatment of  theory and practical implementation in Register-based statistics. It begins by defining the area, before explaining how to structure such systems, as well as detailing alternative approaches. It explains how to create statistical registers, how to implement quality assurance, and the use of IT systems for register-based statistics. Further to this, clear details are given about the practicalities of implementing such statistical methods, such as protection of privacy and the coordination and coherence of such an undertaking. Thi

  18. Validation of hospital register-based diagnosis of Parkinson's disease

    DEFF Research Database (Denmark)

    Wermuth, Lene; Lassen, Christina Funch; Himmerslev, Liselotte

    2012-01-01

    Denmark has a long-standing tradition of maintaining one of the world's largest health science specialized register data bases as the National Hospital Register (NHR). To estimate the prevalence and incidence of diseases, the correctness of the diagnoses recorded is critical. Parkinson's disease...... (PD) is a neurodegenerative disorder and only 75-80% of patients with parkinsonism will have idiopathic PD (iPD). It is necessary to follow patients in order to determine if some of them will develop other neurodegenerative diseases and a one-time-only diagnostic code for iPD reported in the register...

  19. Register-based studies of cancer screening effects

    DEFF Research Database (Denmark)

    Von Euler-Chelpin, My; Lynge, Elsebeth; Rebolj, Matejka

    2011-01-01

    INTRODUCTION: There are two organised cancer screening programmes in Denmark, against cervical and breast cancers. The aim with this study was to give an overview of the available register-based research regarding these two programmes, to demonstrate the usefulness of data from the national regis...

  20. A quantum search algorithm of two entangled registers to realize quantum discrete Fourier transform of signal processing

    International Nuclear Information System (INIS)

    Pang Chaoyang; Hu Benqiong

    2008-01-01

    The discrete Fourier transform (DFT) is the base of modern signal processing. 1-dimensional fast Fourier transform (ID FFT) and 2D FFT have time complexity O (N log N) and O (N 2 log N) respectively. Since 1965, there has been no more essential breakthrough for the design of fast DFT algorithm. DFT has two properties. One property is that DFT is energy conservation transform. The other property is that many DFT coefficients are close to zero. The basic idea of this paper is that the generalized Grover's iteration can perform the computation of DFT which acts on the entangled states to search the big DFT coefficients until these big coefficients contain nearly all energy. One-dimensional quantum DFT (ID QDFT) and two-dimensional quantum DFT (2D QDFT) are presented in this paper. The quantum algorithm for convolution estimation is also presented in this paper. Compared with FFT, ID and 2D QDFT have time complexity O(√N) and O (N) respectively. QDFT and quantum convolution demonstrate that quantum computation to process classical signal is possible. (general)

  1. Isotope-based quantum information

    International Nuclear Information System (INIS)

    Plekhanov, Vladimir G.

    2012-01-01

    The present book provides to the main ideas and techniques of the rapid progressing field of quantum information and quantum computation using isotope - mixed materials. It starts with an introduction to the isotope physics and then describes of the isotope - based quantum information and quantum computation. The ability to manipulate and control electron and/or nucleus spin in semiconductor devices provides a new route to expand the capabilities of inorganic semiconductor-based electronics and to design innovative devices with potential application in quantum computing. One of the major challenges towards these objectives is to develop semiconductor-based systems and architectures in which the spatial distribution of spins and their properties can be controlled. For instance, to eliminate electron spin decoherence resulting from hyperfine interaction due to nuclear spin background, isotopically controlled devices are needed (i.e., nuclear spin-depleted). In other emerging concepts, the control of the spatial distribution of isotopes with nuclear spins is a prerequisite to implement the quantum bits (or qbits). Therefore, stable semiconductor isotopes are important elements in the development of solid-state quantum information. There are not only different algorithms of quantum computation discussed but also the different models of quantum computers are presented. With numerous illustrations this small book is of great interest for undergraduate students taking courses in mesoscopic physics or nanoelectronics as well as quantum information, and academic and industrial researches working in this field.

  2. Quantum signature scheme based on a quantum search algorithm

    International Nuclear Information System (INIS)

    Yoon, Chun Seok; Kang, Min Sung; Lim, Jong In; Yang, Hyung Jin

    2015-01-01

    We present a quantum signature scheme based on a two-qubit quantum search algorithm. For secure transmission of signatures, we use a quantum search algorithm that has not been used in previous quantum signature schemes. A two-step protocol secures the quantum channel, and a trusted center guarantees non-repudiation that is similar to other quantum signature schemes. We discuss the security of our protocol. (paper)

  3. Spin texture readout of a Moore-Read topological quantum register

    NARCIS (Netherlands)

    Romers, J.C.; Schoutens, K.

    2012-01-01

    We study the composite charged spin texture (CST) over the Moore-Read quantum Hall state that arises when a collection of elementary CSTs is moved to the same location. Following an algebraic approach based on the characteristic pair correlations of the Moore-Read state, we find that the spin

  4. Isotope-based quantum information

    CERN Document Server

    G Plekhanov, Vladimir

    2012-01-01

    The present book provides to the main ideas and techniques of the rapid progressing field of quantum information and quantum computation using isotope - mixed materials. It starts with an introduction to the isotope physics and then describes of the isotope - based quantum information and quantum computation. The ability to manipulate and control electron and/or nucleus spin in semiconductor devices provides a new route to expand the capabilities of inorganic semiconductor-based electronics and to design innovative devices with potential application in quantum computing. One of the major challenges towards these objectives is to develop semiconductor-based systems and architectures in which the spatial distribution of spins and their properties can be controlled. For instance, to eliminate electron spin decoherence resulting from hyperfine interaction due to nuclear spin background, isotopically controlled devices are needed (i.e., nuclear spin-depleted). In other emerging concepts, the control of the spatial...

  5. Quantum measurement and real-time feedback with a spin-register in diamond

    NARCIS (Netherlands)

    Blok, M.S.

    2015-01-01

    Gaining precise control over quantum systems is crucial for applications in quantum information processing and quantum sensing and to perform experimental tests of quantum mechanics. The experiments presented in this thesis implement quantum measurements and real-time feedback protocols that can

  6. Novel Quantum Secret Sharing and Controlled Communication Schemes Based on Einstein–Podolsky–Rosen Correlations

    International Nuclear Information System (INIS)

    Yuan, Li; Gui-Hua, Zeng

    2009-01-01

    Employing quantum registers, we first proposed a novel (2, 3) quantum threshold scheme based on Einstein–Podolsky–Rosen (EPR) correlations in this letter. Motivated by the present threshold scheme, we also propose a controlled communication scheme to transmit the secret message with a controller. In the communication protocol, the encoded quantum message carried by particles sequence, is transmitted by legitimate communicators

  7. Spin-based quantum computation in multielectron quantum dots

    OpenAIRE

    Hu, Xuedong; Sarma, S. Das

    2001-01-01

    In a quantum computer the hardware and software are intrinsically connected because the quantum Hamiltonian (or more precisely its time development) is the code that runs the computer. We demonstrate this subtle and crucial relationship by considering the example of electron-spin-based solid state quantum computer in semiconductor quantum dots. We show that multielectron quantum dots with one valence electron in the outermost shell do not behave simply as an effective single spin system unles...

  8. Nanophotonic quantum computer based on atomic quantum transistor

    International Nuclear Information System (INIS)

    Andrianov, S N; Moiseev, S A

    2015-01-01

    We propose a scheme of a quantum computer based on nanophotonic elements: two buses in the form of nanowaveguide resonators, two nanosized units of multiatom multiqubit quantum memory and a set of nanoprocessors in the form of photonic quantum transistors, each containing a pair of nanowaveguide ring resonators coupled via a quantum dot. The operation modes of nanoprocessor photonic quantum transistors are theoretically studied and the execution of main logical operations by means of them is demonstrated. We also discuss the prospects of the proposed nanophotonic quantum computer for operating in high-speed optical fibre networks. (quantum computations)

  9. Nanophotonic quantum computer based on atomic quantum transistor

    Energy Technology Data Exchange (ETDEWEB)

    Andrianov, S N [Institute of Advanced Research, Academy of Sciences of the Republic of Tatarstan, Kazan (Russian Federation); Moiseev, S A [Kazan E. K. Zavoisky Physical-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, Kazan (Russian Federation)

    2015-10-31

    We propose a scheme of a quantum computer based on nanophotonic elements: two buses in the form of nanowaveguide resonators, two nanosized units of multiatom multiqubit quantum memory and a set of nanoprocessors in the form of photonic quantum transistors, each containing a pair of nanowaveguide ring resonators coupled via a quantum dot. The operation modes of nanoprocessor photonic quantum transistors are theoretically studied and the execution of main logical operations by means of them is demonstrated. We also discuss the prospects of the proposed nanophotonic quantum computer for operating in high-speed optical fibre networks. (quantum computations)

  10. A molecular shift register based on electron transfer

    Science.gov (United States)

    Hopfield, J. J.; Onuchic, Josenelson; Beratan, David N.

    1988-01-01

    An electronic shift-register memory at the molecular level is described. The memory elements are based on a chain of electron-transfer molecules and the information is shifted by photoinduced electron-transfer reactions. This device integrates designed electronic molecules onto a very large scale integrated (silicon microelectronic) substrate, providing an example of a 'molecular electronic device' that could actually be made. The design requirements for such a device and possible synthetic strategies are discussed. Devices along these lines should have lower energy usage and enhanced storage density.

  11. Control, measurement and entanglement of remote quantum spin registers in diamond

    NARCIS (Netherlands)

    Bernien, H.

    2014-01-01

    A quantum network is the essential resource for distributed quantum computation and the enabling technology for secure quantum communication over large distances. Setting up such a network would require establishing quantum connections between local nodes which are capable of generating, processing

  12. Quantum cost optimized design of 4-bit reversible universal shift register using reduced number of logic gate

    Science.gov (United States)

    Maity, H.; Biswas, A.; Bhattacharjee, A. K.; Pal, A.

    In this paper, we have proposed the design of quantum cost (QC) optimized 4-bit reversible universal shift register (RUSR) using reduced number of reversible logic gates. The proposed design is very useful in quantum computing due to its low QC, less no. of reversible logic gate and less delay. The QC, no. of gates, garbage outputs (GOs) are respectively 64, 8 and 16 for proposed work. The improvement of proposed work is also presented. The QC is 5.88% to 70.9% improved, no. of gate is 60% to 83.33% improved with compared to latest reported result.

  13. Graphene based quantum dots.

    Science.gov (United States)

    Zhang, H G; Hu, H; Pan, Y; Mao, J H; Gao, M; Guo, H M; Du, S X; Greber, T; Gao, H-J

    2010-08-04

    Laterally localized electronic states are identified on a single layer of graphene on ruthenium by low temperature scanning tunneling spectroscopy (STS). The individual states are separated by 3 nm and comprise regions of about 90 carbon atoms. This constitutes a highly regular quantum dot-array with molecular precision. It is evidenced by quantum well resonances (QWRs) with energies that relate to the corrugation of the graphene layer. The dI/dV conductance spectra are modeled by a layer height dependent potential-well with a delta-function potential that describes the barrier for electron penetration into graphene. The resulting QWRs are strongest and lowest in energy on the isolated 'hill' regions with a diameter of 2 nm, where the graphene is decoupled from the surface.

  14. Determining registered nurses' readiness for evidence-based practice.

    Science.gov (United States)

    Thiel, Linda; Ghosh, Yashowanto

    2008-01-01

    As health care systems worldwide move toward instituting evidence-based practice (EBP), its implementation can be challenging. Conducting a baseline assessment to determine nurses' readiness for EBP presents opportunities to plan strategies before implementation. Although a growing body of research literature is focused on implementing EBP, little attention has been paid to assessing nurses' readiness for EBP. The purpose of this study was to assess registered nurses' readiness for EBP in a moderate-sized acute care hospital in the Midwestern United States before implementation of a hospital-wide nursing EBP initiative. A descriptive cross-sectional survey design was used; 121 registered nurses completed the survey. The participants (n= 121) completed the 64-item Nurses' Readiness for Evidence-Based Practice Survey that allowed measurement of information needs, knowledge and skills, culture, and attitudes. Data were analyzed using descriptive statistics and a post hoc analysis. The majority (72.5%) of respondents indicated that when they needed information, they consulted colleagues and peers rather than using journals and books; 24% of nurses surveyed used the health database, Cumulative Index to Nursing & Allied Health Literature (CINAHL). The respondents perceived their EBP knowledge level as moderate. Cultural EBP scores were moderate, with unit scores being higher than organizational scores. The nurses' attitudes toward EBP were positive. The post hoc analysis showed many significant correlations. Nurses have access to technological resources and perceive that they have the ability to engage in basic information gathering but not in higher level evidence gathering. The elements important to EBP such as a workplace culture and positive attitudes are present and can be built upon. A "site-specific" baseline assessment provides direction in planning EBP initiatives. The Nurses' Readiness for EBP Survey is a streamlined tool with established reliability and

  15. Gender-based wage differentials among registered dietitians.

    Science.gov (United States)

    Pollard, Prudence; Taylor, Maxine; Daher, Noha

    2007-01-01

    The debate on compensation equity is broad-based, addressing many organizational, personal, and outcome factors. Central to compensation philosophy is the issue of gender equity. Health care, like many other industries, remains fraught with gender inequity in compensation. This inequity is partially explained by choice of practice area. However, much remains unexplained. Health care is a female-dominated industry with most of the women working in the allied health professions (eg, nurses, dietitians, etc). Registered dietitians (RD) may experience wage discrimination, similar to registered nurses, but prior to the present study, the assumption was not tested. Using data from the first comprehensive study of RD compensation, we examined gender equity in total cash compensation to RDs. Data were collected on total cash compensation, and questions focused on career progression and work outcomes. For purposes of our study, we analyzed data on 5,477 full-time RDs. Ninety-six percent were women, the median age was 43, and median total cash compensation for RDs employed in the position for at least 1 year was $45,500.00. Women earned $45,285.00 and men earned $50,250.00. A median wage gap of $4,965.00 between women and men was observed. Variability in total cash compensation to women was best explained by size of budget, years of experience, work setting, and educational level. Variability for men was explained by size of budget, years of experience, educational level, and employer status. Conclusions suggest that given the wage discrimination that female RDs experience, work organizations should evaluate their pay plans to monitor pay equity. Factors that women can manage to receive compensation that is equal to that of the men include size of budgets they manage, years of experience in the field, employer status, work setting, and educational level attained. Findings are useful for career advisers, human resource specialists, compensation specialists, supervisors, RDs

  16. Critical points based register-concurrency autotuning for GPUs

    NARCIS (Netherlands)

    Li, A.; Song, S.L.; Kumar, A.; Zhang, E.Z.; Chavarría-Miranda, D.; Corporaal, H.

    2016-01-01

    The unprecedented prevalence of GPGPU is largely attributed to its abundant on-chip register resources, which allow massively concurrent threads and extremely fast context switch. However, due to internal memory size constraints, there is a tradeoff between the per-thread register usage and the

  17. Becoming a web-based learner: registered nurses' experiences.

    Science.gov (United States)

    Atack, Lynda

    2003-11-01

    The purpose of the study was to describe Registered Nurses' experiences when taking a web-based course from either the workplace or home, and the impact of their learning on clinical practice. Little is known about the web-based learners' experience, particularly when courses are accessed from the nursing practice setting. Even less is known about whether nurses transfer their web-based learning to clinical practice. A qualitative design employing focus group interviews was used. Participants included hospital and community nurses from three Canadian provinces and one territory. Data were collected at three points over a 6-month period and analysed using a thematic analysis process. These findings emanate from a larger study using survey method and focus group interviews. The focus group interviews captured the hurdles nurses faced during the first weeks when they struggled with technology, re-framed their views of teaching and adjusted to web-based learning from home and work. These first stressful weeks were followed by a period during which nurses developed relationships with the teacher and peers that enabled them to focus on learning and prevented attrition. Most nurses reported the web course was convenient and that they would be interested and comfortable using technology for learning and work purposes in the future. Six weeks after the course was completed, nurses articulated a number of ways the course had improved their practice. Initial weeks in a web-based course can be very challenging for novice Internet users, however, most nurses who completed the course reported a positive learning experience. Nurses, employers and educators should evaluate computer skills, computer access and the learning environment when preparing for web-based learning.

  18. Obesity research based on the Copenhagen School Health Records Register

    DEFF Research Database (Denmark)

    Baker, Jennifer L; Sørensen, Thorkild I A

    2011-01-01

    INTRODUCTION: To summarise key findings from research performed using data from the Copenhagen School Health Records Register over the last 30 years with a main focus on obesity-related research. The register contains computerised anthropometric information on 372,636 schoolchildren from the capi......INTRODUCTION: To summarise key findings from research performed using data from the Copenhagen School Health Records Register over the last 30 years with a main focus on obesity-related research. The register contains computerised anthropometric information on 372,636 schoolchildren from...... the capital city of Denmark. Additional information on the cohort members has been obtained via linkages with population studies and national registers. RESEARCH TOPICS: Studies using data from the register have made important contributions in the areas of the aetiology of obesity, the development...... of the obesity epidemic, and the long-term health consequences of birth weight as well as body size and growth in childhood. CONCLUSION: Research using this unique register is ongoing, and its contributions to the study of obesity as well as other topics will continue for years to come....

  19. Quantum networks based on cavity QED

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, Stephan; Bochmann, Joerg; Figueroa, Eden; Hahn, Carolin; Kalb, Norbert; Muecke, Martin; Neuzner, Andreas; Noelleke, Christian; Reiserer, Andreas; Uphoff, Manuel; Rempe, Gerhard [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching (Germany)

    2014-07-01

    Quantum repeaters require an efficient interface between stationary quantum memories and flying photons. Single atoms in optical cavities are ideally suited as universal quantum network nodes that are capable of sending, storing, retrieving, and even processing quantum information. We demonstrate this by presenting an elementary version of a quantum network based on two identical nodes in remote, independent laboratories. The reversible exchange of quantum information and the creation of remote entanglement are achieved by exchange of a single photon. Quantum teleportation is implemented using a time-resolved photonic Bell-state measurement. Quantum control over all degrees of freedom of the single atom also allows for the nondestructive detection of flying photons and the implementation of a quantum gate between the spin state of the atom and the polarization of a photon upon its reflection from the cavity. Our approach to quantum networking offers a clear perspective for scalability and provides the essential components for the realization of a quantum repeater.

  20. Ammonia-based quantum computer

    International Nuclear Information System (INIS)

    Ferguson, Andrew J.; Cain, Paul A.; Williams, David A.; Briggs, G. Andrew D.

    2002-01-01

    We propose a scheme for quantum computation using two eigenstates of ammonia or similar molecules. Individual ammonia molecules are confined inside fullerenes and used as two-level qubit systems. Interaction between these ammonia qubits takes place via the electric dipole moments, and in particular we show how a controlled-NOT gate could be implemented. After computation the qubit is measured with a single-electron electrometer sensitive enough to differentiate between the dipole moments of different states. We also discuss a possible implementation based on a quantum cellular automaton

  1. Validity of a hospital-based obstetric register using medical records as reference

    DEFF Research Database (Denmark)

    Brixval, Carina Sjöberg; Thygesen, Lau Caspar; Johansen, Nanna Roed

    2015-01-01

    BACKGROUND: Data from hospital-based registers and medical records offer valuable sources of information for clinical and epidemiological research purposes. However, conducting high-quality epidemiological research requires valid and complete data sources. OBJECTIVE: To assess completeness...... and validity of a hospital-based clinical register - the Obstetric Database - using a national register and medical records as references. METHODS: We assessed completeness of a hospital-based clinical register - the Obstetric Database - by linking data from all women registered in the Obstetric Database...... Database therefore offers a valuable source for examining clinical, administrative, and research questions....

  2. Reveal quantum correlation in complementary bases

    OpenAIRE

    Shengjun Wu; Zhihao Ma; Zhihua Chen; Sixia Yu

    2014-01-01

    An essential feature of genuine quantum correlation is the simultaneous existence of correlation in complementary bases. We reveal this feature of quantum correlation by defining measures based on invariance under a basis change. For a bipartite quantum state, the classical correlation is the maximal correlation present in a certain optimum basis, while the quantum correlation is characterized as a series of residual correlations in the mutually unbiased bases. Compared with other approaches ...

  3. Building a population-based diabetes register: an Italian experience.

    Science.gov (United States)

    Ballotari, Paola; Chiatamone Ranieri, Sofia; Vicentini, Massimo; Caroli, Stefania; Gardini, Andrea; Rodolfi, Rossella; Crucco, Roberto; Greci, Marina; Manicardi, Valeria; Giorgi Rossi, Paolo

    2014-01-01

    To describe the methodology used to set up the Reggio Emilia (northern Italy) Diabetes Register. The prevalence estimates on December 31st, 2009 are also provided. The Diabetes Register covers all residents in the Reggio Emilia province. The register was created by deterministic linkage of six routinely collected data sources through a definite algorithm able to ascertain cases and to distinguish type of diabetes and model of care: Hospital Discharge, Drug Dispensation, Biochemistry Laboratory, Disease-specific Exemption, Diabetes Outpatient Clinics, and Mortality databases. Using these data, we estimated crude prevalence on December 31st, 2009 by sex, age groups, and type of diabetes. There were 25,425 ascertained prevalent cases on December 31st, 2009. Drug Dispensation and Exemption databases made the greatest contribution to prevalence. Analyzing overlapping sources, more than 80% of cases were reported by at least two sources. Crude prevalence was 4.8% and 5.9% for the whole population and for people aged 18 years and over, respectively. Males accounted for 53.6%. Type 1 diabetes accounted for 3.8% of cases, while people with Type 2 diabetes were the overriding majority (91.2%), and Diabetes Outpatient Clinics treated 75.4% of people with Type 2 diabetes. The Register is able to quantify the burden of disease, the first step in planning, implementing, and monitoring appropriate interventions. All data sources contributed to completeness and/or accuracy of the Register. Although all cases are identified by deterministic record linkage, manual revision and General Practitioner involvement are still necessary when information is insufficient or conflicting. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Benchmarking gate-based quantum computers

    Science.gov (United States)

    Michielsen, Kristel; Nocon, Madita; Willsch, Dennis; Jin, Fengping; Lippert, Thomas; De Raedt, Hans

    2017-11-01

    With the advent of public access to small gate-based quantum processors, it becomes necessary to develop a benchmarking methodology such that independent researchers can validate the operation of these processors. We explore the usefulness of a number of simple quantum circuits as benchmarks for gate-based quantum computing devices and show that circuits performing identity operations are very simple, scalable and sensitive to gate errors and are therefore very well suited for this task. We illustrate the procedure by presenting benchmark results for the IBM Quantum Experience, a cloud-based platform for gate-based quantum computing.

  5. Rough set classification based on quantum logic

    Science.gov (United States)

    Hassan, Yasser F.

    2017-11-01

    By combining the advantages of quantum computing and soft computing, the paper shows that rough sets can be used with quantum logic for classification and recognition systems. We suggest the new definition of rough set theory as quantum logic theory. Rough approximations are essential elements in rough set theory, the quantum rough set model for set-valued data directly construct set approximation based on a kind of quantum similarity relation which is presented here. Theoretical analyses demonstrate that the new model for quantum rough sets has new type of decision rule with less redundancy which can be used to give accurate classification using principles of quantum superposition and non-linear quantum relations. To our knowledge, this is the first attempt aiming to define rough sets in representation of a quantum rather than logic or sets. The experiments on data-sets have demonstrated that the proposed model is more accuracy than the traditional rough sets in terms of finding optimal classifications.

  6. Quantum election scheme based on anonymous quantum key distribution

    International Nuclear Information System (INIS)

    Zhou Rui-Rui; Yang Li

    2012-01-01

    An unconditionally secure authority-certified anonymous quantum key distribution scheme using conjugate coding is presented, based on which we construct a quantum election scheme without the help of an entanglement state. We show that this election scheme ensures the completeness, soundness, privacy, eligibility, unreusability, fairness, and verifiability of a large-scale election in which the administrator and counter are semi-honest. This election scheme can work even if there exist loss and errors in quantum channels. In addition, any irregularity in this scheme is sensible. (general)

  7. A register-based study of variations in services received among dental care attenders

    DEFF Research Database (Denmark)

    Rosing, Kasper; Hede, Børge; Christensen, Lisa Bøge

    2016-01-01

    . Materials and methods . This retrospective register-based study followed two Danish cohorts, aged 25 and 40, with a dental examination in 2009 (n = 32,351). The dental service data were registered during 2005–2009. The number of dental examinations, individual preventive services (IPS), tooth extractions...

  8. Reflections on Distributive Leadership for Work-Based Mobile Learning of Canadian Registered Nurses

    Science.gov (United States)

    Fahlman, Dorothy

    2017-01-01

    The ubiquity, flexibility, and accessibility of mobile devices can transform how registered nurses in Canada learn beyond the confines of traditional education/training boundaries in their work settings. Many Canadian registered nurses have actively embraced mobile technologies for their work-based learning to meet their competency requirements…

  9. Ultrafast quantum random number generation based on quantum phase fluctuations.

    Science.gov (United States)

    Xu, Feihu; Qi, Bing; Ma, Xiongfeng; Xu, He; Zheng, Haoxuan; Lo, Hoi-Kwong

    2012-05-21

    A quantum random number generator (QRNG) can generate true randomness by exploiting the fundamental indeterminism of quantum mechanics. Most approaches to QRNG employ single-photon detection technologies and are limited in speed. Here, we experimentally demonstrate an ultrafast QRNG at a rate over 6 Gbits/s based on the quantum phase fluctuations of a laser operating near threshold. Moreover, we consider a potential adversary who has partial knowledge on the raw data and discuss how one can rigorously remove such partial knowledge with postprocessing. We quantify the quantum randomness through min-entropy by modeling our system and employ two randomness extractors--Trevisan's extractor and Toeplitz-hashing--to distill the randomness, which is information-theoretically provable. The simplicity and high-speed of our experimental setup show the feasibility of a robust, low-cost, high-speed QRNG.

  10. A New Quantum Watermarking Based on Quantum Wavelet Transforms

    International Nuclear Information System (INIS)

    Heidari, Shahrokh; Pourarian, Mohammad Rasoul; Naseri, Mosayeb; Gheibi, Reza; Baghfalaki, Masoud; Farouk, Ahmed

    2017-01-01

    Quantum watermarking is a technique to embed specific information, usually the owner’s identification, into quantum cover data such for copyright protection purposes. In this paper, a new scheme for quantum watermarking based on quantum wavelet transforms is proposed which includes scrambling, embedding and extracting procedures. The invisibility and robustness performances of the proposed watermarking method is confirmed by simulation technique. The invisibility of the scheme is examined by the peak-signal-to-noise ratio (PSNR) and the histogram calculation. Furthermore the robustness of the scheme is analyzed by the Bit Error Rate (BER) and the Correlation Two-Dimensional (Corr 2-D) calculation. The simulation results indicate that the proposed watermarking scheme indicate not only acceptable visual quality but also a good resistance against different types of attack. (paper)

  11. Quantum chemistry literature data base

    International Nuclear Information System (INIS)

    Ohno, Kimio; Morokuma, Keiji

    1982-01-01

    Ab initio computations of atomic and molecular electronic structure now appear in so many journals that it is very difficult for interested scientistics to locate proper and comprehensive references. This book is designed to help them and contains more than 2500 references to the literature published in the years 1978-1980. These have been gathered from nineteen well-known international core journals by quantum chemists themselves and the result is a thorough bibliography. Each entry is a full reference consisting of the following items: (1) authors, (2) journal name, volume, page and year, (3) compounds, (4) methods of calculation, (5) basis sets, (6) calculated properties, and (7) comments. For easy access to the references, the reader can consult the compound and author indexes. A short article on the reliability of ab initio calculations is included as an appendix; this gives a rough idea about the accuracy of the calculated results reported. As the book has been complied using the resources of a computer data base of quantum chemistry literature, it is particularly up to date and the authors will be able to provide supplements regularly. This bibliography will be an asset to large departments of chemistry and all university libraries. (orig.)

  12. A Performance Survey on Stack-based and Register-based Virtual Machines

    OpenAIRE

    Fang, Ruijie; Liu, Siqi

    2016-01-01

    Virtual machines have been widely adapted for high-level programming language implementations and for providing a degree of platform neutrality. As the overall use and adaptation of virtual machines grow, the overall performance of virtual machines has become a widely-discussed topic. In this paper, we present a survey on the performance differences of the two most widely adapted types of virtual machines - the stack-based virtual machine and the register-based virtual machine - using various...

  13. LSB Based Quantum Image Steganography Algorithm

    Science.gov (United States)

    Jiang, Nan; Zhao, Na; Wang, Luo

    2016-01-01

    Quantum steganography is the technique which hides a secret message into quantum covers such as quantum images. In this paper, two blind LSB steganography algorithms in the form of quantum circuits are proposed based on the novel enhanced quantum representation (NEQR) for quantum images. One algorithm is plain LSB which uses the message bits to substitute for the pixels' LSB directly. The other is block LSB which embeds a message bit into a number of pixels that belong to one image block. The extracting circuits can regain the secret message only according to the stego cover. Analysis and simulation-based experimental results demonstrate that the invisibility is good, and the balance between the capacity and the robustness can be adjusted according to the needs of applications.

  14. Register-based estimates of parents' coresidence in Sweden, 1969-2007

    Directory of Open Access Journals (Sweden)

    Elizabeth Thomson

    2013-12-01

    Full Text Available Background: Many of the dramatic changes in family formation and dissolution observed in wealthy countries over the past 60 years are tracked through vital statistics or censuses. The signature change in family behavior -- non-marital cohabitation -- is not, however, registered in most settings. Objective: We evaluate the quality of new register-based estimates of parents' union status at birth and of separation during the childrearing years. Methods: Parents of a common child are identified through the Multi-Generation Register that links each child to each parent and therefore each parent to each other. The Total Population Register identifies the property at which each parent is registered at the end of each year. We use the five-year censuses 1960-1990 as one standard of comparison because the censuses identify the dwelling unit for each parent on the census date. Results: Property-based estimates of parents' coresidence compare very well to census reports. Register-based estimates are virtually identical with those produced from the 1992 Swedish Fertility and Family Survey; differences between register estimates and those produced from the 1991 and 2000 Level of Living Survey can be explained by differences in measurement of marriage and cohabitation. Conclusions: Estimates of parents' cohabitation based on annual, property-level registration are of sufficient quality for their use in substantive analyses of union status at birth and parents' separation in Sweden. Comments: Although register-based estimates of parents' coresidence at a child's birth or afterwards can be generated only for a select group of countries, their use can be fruitful for understanding more general processes of family change. Centralized administrative registers exist in many countries but have not been made fully available for research therefore losing much of the potential value.

  15. Cardiovascular disease in patients with osteogenesis imperfecta — a nationwide, register-based cohort study

    OpenAIRE

    Folkestad, Lars; Hald, Jannie Dahl; Gram, Jeppe; Langdahl, Bente L.; Hermann, Anne Pernille; Diederichsen, Axel CP; Abrahamsen, Bo; Brixen, Kim

    2016-01-01

    BACKGROUND: Osteogenesis imperfecta (OI) is a hereditary connective tissue disease often due to mutations in genes coding for type 1 collagen. Collagen type 1 is important in the development of the heart and vasculature. Little is known about the risk of cardiovascular disease (CVD) in OI.OBJECTIVE: To investigate the risk of symptomatic CVD in OI.DESIGN: A Danish nationwide, population-based and register-based longitudinal open cohort study.PARTICIPANTS: All patients registered with the diag...

  16. Opinion dynamics model based on quantum formalism

    Energy Technology Data Exchange (ETDEWEB)

    Artawan, I. Nengah, E-mail: nengahartawan@gmail.com [Theoretical Physics Division, Department of Physics, Udayana University (Indonesia); Trisnawati, N. L. P., E-mail: nlptrisnawati@gmail.com [Biophysics, Department of Physics, Udayana University (Indonesia)

    2016-03-11

    Opinion dynamics model based on quantum formalism is proposed. The core of the quantum formalism is on the half spin dynamics system. In this research the implicit time evolution operators are derived. The analogy between the model with Deffuant dan Sznajd models is discussed.

  17. Towards quantum-based privacy and voting

    International Nuclear Information System (INIS)

    Hillery, Mark; Ziman, Mario; Buzek, Vladimir; Bielikova, Martina

    2006-01-01

    The privacy of communicating participants is often of paramount importance, but in some situations it is an essential condition. A typical example is a fair (secret) voting. We analyze in detail communication privacy based on quantum resources, and we propose new quantum protocols. Possible generalizations that would lead to voting schemes are discussed

  18. Deterministic and efficient quantum cryptography based on Bell's theorem

    International Nuclear Information System (INIS)

    Chen Zengbing; Pan Jianwei; Zhang Qiang; Bao Xiaohui; Schmiedmayer, Joerg

    2006-01-01

    We propose a double-entanglement-based quantum cryptography protocol that is both efficient and deterministic. The proposal uses photon pairs with entanglement both in polarization and in time degrees of freedom; each measurement in which both of the two communicating parties register a photon can establish one and only one perfect correlation, and thus deterministically create a key bit. Eavesdropping can be detected by violation of local realism. A variation of the protocol shows a higher security, similar to the six-state protocol, under individual attacks. Our scheme allows a robust implementation under the current technology

  19. Deterministic and efficient quantum cryptography based on Bell's theorem

    International Nuclear Information System (INIS)

    Chen, Z.-B.; Zhang, Q.; Bao, X.-H.; Schmiedmayer, J.; Pan, J.-W.

    2005-01-01

    Full text: We propose a novel double-entanglement-based quantum cryptography protocol that is both efficient and deterministic. The proposal uses photon pairs with entanglement both in polarization and in time degrees of freedom; each measurement in which both of the two communicating parties register a photon can establish a key bit with the help of classical communications. Eavesdropping can be detected by checking the violation of local realism for the detected events. We also show that our protocol allows a robust implementation under current technology. (author)

  20. Implementation of anaphylaxis management guidelines: a register-based study.

    Directory of Open Access Journals (Sweden)

    Linus Grabenhenrich

    Full Text Available BACKGROUND: Anaphylaxis management guidelines recommend the use of intramuscular adrenaline in severe reactions, complemented by antihistamines and corticoids; secondary prevention includes allergen avoidance and provision of self-applicable first aid drugs. Gaps between recommendations and their implementation have been reported, but only in confined settings. Hence, we analysed nation-wide data on the management of anaphylaxis, evaluating the implementation of guidelines. METHODS: Within the anaphylaxis registry, allergy referral centres across Germany, Austria and Switzerland provided data on severe anaphylaxis cases. Based on patient records, details on reaction circumstances, diagnostic workup and treatment were collected via online questionnaire. Report of anaphylaxis through emergency physicians allowed for validation of registry data. RESULTS: 2114 severe anaphylaxis patients from 58 centres were included. 8% received adrenaline intravenously, 4% intramuscularly; 50% antihistamines, and 51% corticoids. Validation data indicated moderate underreporting of first aid drugs in the Registry. 20% received specific instructions at the time of the reaction; 81% were provided with prophylactic first aid drugs at any time. CONCLUSION: There is a distinct discrepancy between current anaphylaxis management guidelines and their implementation. To improve patient care, a revised approach for medical education and training on the management of severe anaphylaxis is warranted.

  1. Children with hemodynamically significant congenital heart disease can be identified through population-based registers

    DEFF Research Database (Denmark)

    Bergman, Gunnar; Hærskjold, Ann; Stensballe, Lone Graff

    2015-01-01

    BACKGROUND: Epidemiological research is facilitated in Sweden by a history of national health care registers, making large unselected national cohort studies possible. However, for complex clinical populations, such as children with congenital heart disease (CHD), register-based studies...... are challenged by registration limitations. For example, the diagnostic code system International Classification of Diseases, 10th version (ICD-10) does not indicate the clinical significance of abnormalities, therefore may be of limited use if used as the sole parameter in epidemiological research. Palivizumab...

  2. Corrosion behavior of Haynes {sup registered} 230 {sup registered} nickel-based super-alloys for integrated coal gasification combined cycle syngas plants. A plant exposure study

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sungkyu; Lee, Jieun; Kang, Suk-Hwan; Lee, Seung-Jong; Yun, Yongseung [Institute for Advanced Engineering (IAE), Gyeonggi-do (Korea, Republic of). Plant Engineering Center; Kim, Min Jung [Sungkyunkwan Univ, Gyeonggi-do (Korea, Republic of). Advanced Materials Technology Research Center

    2015-07-01

    The corrosion behavior of commercially available Haynes {sup registered} 230 {sup registered} nickel-based alloy samples was investigated by exposure to coal-gasifying integrated coal gasification combined cycle pilot plant facilities affiliated with the Institute for Advanced Engineering (2.005 MPa and 160-300 C). The morphological and microstructural analyses of the exposed samples were conducted using scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis on the external surface of the recovered corrosion test samples to obtain information of the corrosion scale. These analyses based on the pre- and post-exposure corrosion test samples combined with thermodynamic Ellingham-Pourbaix stability diagrams provided preliminary insight into the mechanism of the observed corrosion behavior prevailing in the piping materials that connected the particulate removal unit and water scrubber of the integrated coal gasification combined cycle pilot plant. Uniform material wastage was observed after 46 hours of operation, and a preliminary corrosion mechanism was suggested: the observed material waste and corrosion behavior of the Haynes {sup registered} 230 {sup registered} nickel-based alloy samples cut off from the coal syngas integrated coal gasification combined cycle plant were explained by the formation of discontinuous (complex) oxide phases and subsequent chlorine-induced active oxidation under the predominantly reducing environment encountered. This contribution continues the already published studies of the Fe-Ni-Cr-Co alloy Haynes {sup registered} 556 {sup registered}.

  3. Corrosion behavior of Haynes registered 230 registered nickel-based super-alloys for integrated coal gasification combined cycle syngas plants. A plant exposure study

    International Nuclear Information System (INIS)

    Lee, Sungkyu; Lee, Jieun; Kang, Suk-Hwan; Lee, Seung-Jong; Yun, Yongseung; Kim, Min Jung

    2015-01-01

    The corrosion behavior of commercially available Haynes registered 230 registered nickel-based alloy samples was investigated by exposure to coal-gasifying integrated coal gasification combined cycle pilot plant facilities affiliated with the Institute for Advanced Engineering (2.005 MPa and 160-300 C). The morphological and microstructural analyses of the exposed samples were conducted using scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis on the external surface of the recovered corrosion test samples to obtain information of the corrosion scale. These analyses based on the pre- and post-exposure corrosion test samples combined with thermodynamic Ellingham-Pourbaix stability diagrams provided preliminary insight into the mechanism of the observed corrosion behavior prevailing in the piping materials that connected the particulate removal unit and water scrubber of the integrated coal gasification combined cycle pilot plant. Uniform material wastage was observed after 46 hours of operation, and a preliminary corrosion mechanism was suggested: the observed material waste and corrosion behavior of the Haynes registered 230 registered nickel-based alloy samples cut off from the coal syngas integrated coal gasification combined cycle plant were explained by the formation of discontinuous (complex) oxide phases and subsequent chlorine-induced active oxidation under the predominantly reducing environment encountered. This contribution continues the already published studies of the Fe-Ni-Cr-Co alloy Haynes registered 556 registered .

  4. Time-to-event methodology improved statistical evaluation in register-based health services research.

    Science.gov (United States)

    Bluhmki, Tobias; Bramlage, Peter; Volk, Michael; Kaltheuner, Matthias; Danne, Thomas; Rathmann, Wolfgang; Beyersmann, Jan

    2017-02-01

    Complex longitudinal sampling and the observational structure of patient registers in health services research are associated with methodological challenges regarding data management and statistical evaluation. We exemplify common pitfalls and want to stimulate discussions on the design, development, and deployment of future longitudinal patient registers and register-based studies. For illustrative purposes, we use data from the prospective, observational, German DIabetes Versorgungs-Evaluation register. One aim was to explore predictors for the initiation of a basal insulin supported therapy in patients with type 2 diabetes initially prescribed to glucose-lowering drugs alone. Major challenges are missing mortality information, time-dependent outcomes, delayed study entries, different follow-up times, and competing events. We show that time-to-event methodology is a valuable tool for improved statistical evaluation of register data and should be preferred to simple case-control approaches. Patient registers provide rich data sources for health services research. Analyses are accompanied with the trade-off between data availability, clinical plausibility, and statistical feasibility. Cox' proportional hazards model allows for the evaluation of the outcome-specific hazards, but prediction of outcome probabilities is compromised by missing mortality information. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Creating Very True Quantum Algorithms for Quantum Energy Based Computing

    Science.gov (United States)

    Nagata, Koji; Nakamura, Tadao; Geurdes, Han; Batle, Josep; Abdalla, Soliman; Farouk, Ahmed; Diep, Do Ngoc

    2018-04-01

    An interpretation of quantum mechanics is discussed. It is assumed that quantum is energy. An algorithm by means of the energy interpretation is discussed. An algorithm, based on the energy interpretation, for fast determining a homogeneous linear function f( x) := s. x = s 1 x 1 + s 2 x 2 + ⋯ + s N x N is proposed. Here x = ( x 1, … , x N ), x j ∈ R and the coefficients s = ( s 1, … , s N ), s j ∈ N. Given the interpolation values (f(1), f(2),...,f(N))=ěc {y}, the unknown coefficients s = (s1(ěc {y}),\\dots , sN(ěc {y})) of the linear function shall be determined, simultaneously. The speed of determining the values is shown to outperform the classical case by a factor of N. Our method is based on the generalized Bernstein-Vazirani algorithm to qudit systems. Next, by using M parallel quantum systems, M homogeneous linear functions are determined, simultaneously. The speed of obtaining the set of M homogeneous linear functions is shown to outperform the classical case by a factor of N × M.

  6. State-Transition-Aware Spilling Heuristic for MLC STT-RAM-Based Registers

    Directory of Open Access Journals (Sweden)

    Yuanhui Ni

    2017-01-01

    Full Text Available Multilevel Cell Spin-Transfer Torque Random Access Memory (MLC STT-RAM is a promising nonvolatile memory technology to build registers for its natural immunity to electromagnetic radiation in rad-hard space environment. Unlike traditional SRAM-based registers, MLC STT-RAM exhibits unbalanced write state transitions due to the fact that the magnetization directions of hard and soft domains cannot be flipped independently. This feature leads to nonuniform costs of write states in terms of latency and energy. However, current SRAM-targeting register allocations do not have a clear understanding of the impact of the different write state-transition costs. As a result, those approaches heuristically select variables to be spilled without considering the spilling priority imposed by MLC STT-RAM. Aiming to address this limitation, this paper proposes a state-transition-aware spilling cost minimization (SSCM policy, to save power when MLC STT-RAM is employed in register design. Specifically, the spilling cost model is first constructed according to the linear combination of different state-transition frequencies. Directed by the proposed cost model, the compiler picks up spilling candidates to achieve lower power and higher performance. Experimental results show that the proposed SSCM technique can save energy by 19.4% and improve the lifetime by 23.2% of MLC STT-RAM-based register design.

  7. Epilepsy in Individuals with a History of Asperger's Syndrome: A Danish Nationwide Register-Based Cohort Study

    Science.gov (United States)

    Mouridsen, Svend Erik; Rich, Bente; Isager, Torben

    2013-01-01

    We performed a nationwide, register-based retrospective follow-up study of epilepsy in all people who were born between January 1, 1980 and June 29, 2006 and registered in the Danish Psychiatric Central Register with Asperger's syndrome on February 7, 2011. All 4,180 identified cases with AS (3,431 males and 749 females) were screened through the…

  8. Silicon based quantum dot hybrid qubits

    Science.gov (United States)

    Kim, Dohun

    2015-03-01

    The charge and spin degrees of freedom of an electron constitute natural bases for constructing quantum two level systems, or qubits, in semiconductor quantum dots. The quantum dot charge qubit offers a simple architecture and high-speed operation, but generally suffers from fast dephasing due to strong coupling of the environment to the electron's charge. On the other hand, quantum dot spin qubits have demonstrated long coherence times, but their manipulation is often slower than desired for important future applications. This talk will present experimental progress of a `hybrid' qubit, formed by three electrons in a Si/SiGe double quantum dot, which combines desirable characteristics (speed and coherence) in the past found separately in qubits based on either charge or spin degrees of freedom. Using resonant microwaves, we first discuss qubit operations near the `sweet spot' for charge qubit operation. Along with fast (>GHz) manipulation rates for any rotation axis on the Bloch sphere, we implement two independent tomographic characterization schemes in the charge qubit regime: traditional quantum process tomography (QPT) and gate set tomography (GST). We also present resonant qubit operations of the hybrid qubit performed on the same device, DC pulsed gate operations of which were recently demonstrated. We demonstrate three-axis control and the implementation of dynamic decoupling pulse sequences. Performing QPT on the hybrid qubit, we show that AC gating yields π rotation process fidelities higher than 93% for X-axis and 96% for Z-axis rotations, which demonstrates efficient quantum control of semiconductor qubits using resonant microwaves. We discuss a path forward for achieving fidelities better than the threshold for quantum error correction using surface codes. This work was supported in part by ARO (W911NF-12-0607), NSF (PHY-1104660), DOE (DE-FG02-03ER46028), and by the Laboratory Directed Research and Development program at Sandia National Laboratories

  9. Operative Complications During Pregnancy After Gastric Bypass—a Register-Based Cohort Study

    DEFF Research Database (Denmark)

    Andreasen, Lisbeth A; Nilas, Lisbeth; Kjær, Mette M

    2014-01-01

    the puerperium. CONCLUSIONS: The incidence of internal herniation during pregnancy was 1 % in our study. Internal herniation may be a serious complication in pregnant women, and both the diagnosis and treatment requires handling by experienced obstetrical, radiological, and surgical staff....... during pregnancy in a national cohort of women with a history of gastric bypass surgery. METHODS: A national, register-based cohort study of all Danish women with a history of gastric bypass surgery who had given birth from 2004 to 2010 was conducted. Surgical codes registered during pregnancy and until...... 120 days postpartum were identified in national registers, and the individual charts were reviewed in relevant cases. RESULTS: Of 286 women giving birth, fourteen women underwent procedures that might be related to the earlier gastric bypass surgery. Three women were operated on suspicion of internal...

  10. Epidemiology of valvular heart disease in a Swedish nationwide hospital-based register study

    DEFF Research Database (Denmark)

    Andell, Pontus; Li, Xinjun; Martinsson, Andreas

    2017-01-01

    OBJECTIVE: Transitions in the spectrum of valvular heart diseases (VHDs) in developed countries over the 20th century have been reported from clinical case series, but large, contemporary population-based studies are lacking. METHODS: We used nationwide registers to identify all patients...

  11. Quantum secret sharing based on quantum error-correcting codes

    International Nuclear Information System (INIS)

    Zhang Zu-Rong; Liu Wei-Tao; Li Cheng-Zu

    2011-01-01

    Quantum secret sharing(QSS) is a procedure of sharing classical information or quantum information by using quantum states. This paper presents how to use a [2k − 1, 1, k] quantum error-correcting code (QECC) to implement a quantum (k, 2k − 1) threshold scheme. It also takes advantage of classical enhancement of the [2k − 1, 1, k] QECC to establish a QSS scheme which can share classical information and quantum information simultaneously. Because information is encoded into QECC, these schemes can prevent intercept-resend attacks and be implemented on some noisy channels. (general)

  12. The Austrian breast implant register: recent trends in implant-based breast surgery.

    Science.gov (United States)

    Wurzer, Paul; Rappl, Thomas; Friedl, Herwig; Kamolz, Lars-Peter; Spendel, Stephan; Hoflehner, Helmut; Parvizi, Daryousch

    2014-12-01

    Due to the fact that the number of breast implant surgeries for cosmetic and medical purposes is rising yearly, a discussion about the quality of service for both patients and physicians is more important than ever. To this end, we reviewed the Austrian Breast Implant Register with one specific question in mind: What are the trends? In the statistical analysis of the Austrian Breast Implant Register, we were able to identify 13,112 registered breast implants between 2004 and 2012. The whole dataset was then divided into medical and cosmetic groups. We focused on device size, surface characteristics, filling material, device placement and incision site. All factors were considered for all examined years. In summary, the most used device had a textured surface (97 %) and silicone gel as the filling material (93 %). The mean size of implants for the cosmetic group was 240 cc, placement was submuscular (58 %) and the incision site was inframammary (67 %). In the medical group, the mean size was 250 cc. Yearly registrations had their peak in 2008 (1,898 registered devices); from this year on, registrations decreased annually. A slight trend away from subglandular placement in the cosmetic group was noted. Also, the usage of implants with polyurethane surface characteristics has increased since 2008. The smooth surface implants had a peak usage in 2006 and their usage decreased steadily from then on whereas the textured surface was steady over the years. Keeping the problems related to the quality of breast implants in mind, we could recommend an obligatory national register. Organisations of surgeons and governments should develop and establish these registers. Furthermore, an all-encompassing international register should be established by the European Union and the American FDA (Food and Drug Administration); this might be useful in comparing the individual country registers and also would help in delivering "evidence based" medicine in cosmetic and medical procedures

  13. Distance Ranging Based on Quantum Entanglement

    International Nuclear Information System (INIS)

    Xiao Jun-Jun; Han Xiao-Chun; Zeng Gui-Hua; Fang Chen; Zhao Jian-Kang

    2013-01-01

    In the quantum metrology, applications of quantum techniques based on entanglement bring in some better performances than conventional approaches. We experimentally investigate an application of entanglement in accurate ranging based on the second-order coherence in the time domain. By a fitting algorithm in the data processing, the optimization results show a precision of ±200 μm at a distance of 1043.3m. In addition, the influence of jamming noise on the ranging scheme is studied. With some different fitting parameters, the result shows that the proposed scheme has a powerful anti-jamming capability for white noise

  14. Opportunistic quantum network coding based on quantum teleportation

    Science.gov (United States)

    Shang, Tao; Du, Gang; Liu, Jian-wei

    2016-04-01

    It seems impossible to endow opportunistic characteristic to quantum network on the basis that quantum channel cannot be overheard without disturbance. In this paper, we propose an opportunistic quantum network coding scheme by taking full advantage of channel characteristic of quantum teleportation. Concretely, it utilizes quantum channel for secure transmission of quantum states and can detect eavesdroppers by means of quantum channel verification. What is more, it utilizes classical channel for both opportunistic listening to neighbor states and opportunistic coding by broadcasting measurement outcome. Analysis results show that our scheme can reduce the times of transmissions over classical channels for relay nodes and can effectively defend against classical passive attack and quantum active attack.

  15. High-Capacity Quantum Secure Direct Communication Based on Quantum Hyperdense Coding with Hyperentanglement

    International Nuclear Information System (INIS)

    Wang Tie-Jun; Li Tao; Du Fang-Fang; Deng Fu-Guo

    2011-01-01

    We present a quantum hyperdense coding protocol with hyperentanglement in polarization and spatial-mode degrees of freedom of photons first and then give the details for a quantum secure direct communication (QSDC) protocol based on this quantum hyperdense coding protocol. This QSDC protocol has the advantage of having a higher capacity than the quantum communication protocols with a qubit system. Compared with the QSDC protocol based on superdense coding with d-dimensional systems, this QSDC protocol is more feasible as the preparation of a high-dimension quantum system is more difficult than that of a two-level quantum system at present. (general)

  16. Quantum Effects in Molecule-Based Nanomagnets

    Science.gov (United States)

    Hill, Stephen

    2005-11-01

    Research into molecule-based-magnets has made immense strides in recent years, with the discoveries of all organic molecular magnets, room temperature 3D ordered permanent magnets, and single-molecule magnets (SMMs), the latter exhibiting a host of spectacular quantum phenomena; for a review, see ref. [1]. SMMs represent a molecular approach to nanoscale and sub-nanoscale magnetic particles. They offer all of the advantages of molecular chemistry as well as displaying the superparamagnetic properties of mesoscale magnetic particles of much larger dimensions. They also straddle the interface between classical and quantum behavior; for example, they exhibit quantum tunneling of their magnetization. I will give a general introduction to this area of research, followed by an overview of recent results obtained using high-frequency (40-800 GHz) electron paramagnetic resonance techniques developed at the University of Florida. These results include: an elucidation of the role of molecular symmetry in the magnetic quantum tunneling phenomenon [2]; and the observation of quantum entanglement between pairs of nanomagnets within a supramolecular dimer [3]. 1. D. Gatteschi and R. Sessoli, Angew. Chem. 42, 268 (2003). 2. E. del Barco et al., J. Low Temp. Phys. 140, 119-174 (2005). 3. S. Hill et al., Science 302, 1015 (2003).

  17. Group representations, error bases and quantum codes

    Energy Technology Data Exchange (ETDEWEB)

    Knill, E

    1996-01-01

    This report continues the discussion of unitary error bases and quantum codes. Nice error bases are characterized in terms of the existence of certain characters in a group. A general construction for error bases which are non-abelian over the center is given. The method for obtaining codes due to Calderbank et al. is generalized and expressed purely in representation theoretic terms. The significance of the inertia subgroup both for constructing codes and obtaining the set of transversally implementable operations is demonstrated.

  18. Quantum Watermarking Scheme Based on INEQR

    Science.gov (United States)

    Zhou, Ri-Gui; Zhou, Yang; Zhu, Changming; Wei, Lai; Zhang, Xiafen; Ian, Hou

    2018-04-01

    Quantum watermarking technology protects copyright by embedding invisible quantum signal in quantum multimedia data. In this paper, a watermarking scheme based on INEQR was presented. Firstly, the watermark image is extended to achieve the requirement of embedding carrier image. Secondly, the swap and XOR operation is used on the processed pixels. Since there is only one bit per pixel, XOR operation can achieve the effect of simple encryption. Thirdly, both the watermark image extraction and embedding operations are described, where the key image, swap operation and LSB algorithm are used. When the embedding is made, the binary image key is changed. It means that the watermark has been embedded. Of course, if the watermark image is extracted, the key's state need detected. When key's state is |1>, this extraction operation is carried out. Finally, for validation of the proposed scheme, both the Signal-to-noise ratio (PSNR) and the security of the scheme are analyzed.

  19. Quantum walks based on an interferometric analogy

    International Nuclear Information System (INIS)

    Hillery, Mark; Bergou, Janos; Feldman, Edgar

    2003-01-01

    There are presently two models for quantum walks on graphs. The ''coined'' walk uses discrete-time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the particle will move. The continuous walk operates with continuous time. Here a third model for quantum walks is proposed, which is based on an analogy to optical interferometers. It is a discrete-time model, and the unitary operator that advances the walk one step depends only on the local structure of the graph on which the walk is taking place. This type of walk also allows us to introduce elements, such as phase shifters, that have no counterpart in classical random walks. Several examples are discussed

  20. Towards a fullerene-based quantum computer

    International Nuclear Information System (INIS)

    Benjamin, Simon C; Ardavan, Arzhang; Briggs, G Andrew D; Britz, David A; Gunlycke, Daniel; Jefferson, John; Jones, Mark A G; Leigh, David F; Lovett, Brendon W; Khlobystov, Andrei N; Lyon, S A; Morton, John J L; Porfyrakis, Kyriakos; Sambrook, Mark R; Tyryshkin, Alexei M

    2006-01-01

    Molecular structures appear to be natural candidates for a quantum technology: individual atoms can support quantum superpositions for long periods, and such atoms can in principle be embedded in a permanent molecular scaffolding to form an array. This would be true nanotechnology, with dimensions of order of a nanometre. However, the challenges of realizing such a vision are immense. One must identify a suitable elementary unit and demonstrate its merits for qubit storage and manipulation, including input/output. These units must then be formed into large arrays corresponding to an functional quantum architecture, including a mechanism for gate operations. Here we report our efforts, both experimental and theoretical, to create such a technology based on endohedral fullerenes or 'buckyballs'. We describe our successes with respect to these criteria, along with the obstacles we are currently facing and the questions that remain to be addressed

  1. Dementia and Traffic Accidents: A Danish Register-Based Cohort Study.

    Science.gov (United States)

    Petersen, Jindong Ding; Siersma, Volkert; Nielsen, Connie Thurøe; Vass, Mikkel; Waldorff, Frans Boch

    2016-09-27

    As a consequence of a rapid growth of an ageing population, more people with dementia are expected on the roads. Little is known about whether these people are at increased risk of road traffic-related accidents. Our study aims to investigate the risk of road traffic-related accidents for people aged 65 years or older with a diagnosis of dementia in Denmark. We will conduct a nationwide population-based cohort study consisting of Danish people aged 65 or older living in Denmark as of January 1, 2008. The cohort is followed for 7 years (2008-2014). Individual's personal data are available in Danish registers and can be linked using a unique personal identification number. A person is identified with dementia if the person meets at least one of the following criteria: (1) a diagnosis of the disease in the Danish National Patient Register or in the Danish Psychiatric Central Research Register, and/or (2) at least one dementia diagnosis-related drug prescription registration in the Danish National Prescription Registry. Police-, hospital-, and emergency room-reported road traffic-related accidents occurred within the study follow-up are defined as the study outcome. Cox proportional hazard regression models are used for the main analysis. Our study protocol has 3 phases including data collection, data analysis, and reporting. The first phase of register-based data collection of 853,228 individual's personal information was completed in August, 2016. The next phase is data analysis, which is expected to be finished before December 2016, and thereafter writing publications based on the findings. The study started in January 2016 and will end in December 2018. This study covers the entire elderly population of Denmark, and thereby will avoid selection bias due to nonparticipation and loss to follow-up. Furthermore, this ensures that the study results are reliable and generalizable. However, underreporting of traffic-related accidents may occur, which will limit estimation

  2. Semihierarchical quantum repeaters based on moderate lifetime quantum memories

    Science.gov (United States)

    Liu, Xiao; Zhou, Zong-Quan; Hua, Yi-Lin; Li, Chuan-Feng; Guo, Guang-Can

    2017-01-01

    The construction of large-scale quantum networks relies on the development of practical quantum repeaters. Many approaches have been proposed with the goal of outperforming the direct transmission of photons, but most of them are inefficient or difficult to implement with current technology. Here, we present a protocol that uses a semihierarchical structure to improve the entanglement distribution rate while reducing the requirement of memory time to a range of tens of milliseconds. This protocol can be implemented with a fixed distance of elementary links and fixed requirements on quantum memories, which are independent of the total distance. This configuration is especially suitable for scalable applications in large-scale quantum networks.

  3. Incidence and prevalence of mental disorders among immigrants and native Finns: a register-based study.

    Science.gov (United States)

    Markkula, Niina; Lehti, Venla; Gissler, Mika; Suvisaari, Jaana

    2017-12-01

    Migrants appear to have a higher risk of mental disorders, but findings vary across country settings and migrant groups. We aimed to assess incidence and prevalence of mental disorders among immigrants and Finnish-born controls in a register-based cohort study. A register-based cohort study of 184.806 immigrants and 185.184 Finnish-born controls (1.412.117 person-years) was conducted. Information on mental disorders according to ICD-10 was retrieved from the Hospital Discharge Register, which covers all public health care use. The incidence of any mental disorder was lower among male (adjusted HR 0.82, 95% CI 0.77-0.87) and female (aHR 0.76, 95% CI 0.72-0.81) immigrants, being lowest among Asian and highest among North African and Middle Eastern immigrants. The incidence of bipolar, depressive and alcohol use disorders was lower among immigrants. Incidence of psychotic disorders was lower among female and not higher among male immigrants, compared with native Finns. Incidence of PTSD was higher among male immigrants (aHR 4.88, 95% CI 3.38-7.05). The risk of mental disorders varies significantly across migrant groups and disorders and is generally lower among immigrants than native Finns.

  4. Electronic shift register memory based on molecular electron-transfer reactions

    Science.gov (United States)

    Hopfield, J. J.; Onuchic, Jose Nelson; Beratan, David N.

    1989-01-01

    The design of a shift register memory at the molecular level is described in detail. The memory elements are based on a chain of electron-transfer molecules incorporated on a very large scale integrated (VLSI) substrate, and the information is shifted by photoinduced electron-transfer reactions. The design requirements for such a system are discussed, and several realistic strategies for synthesizing these systems are presented. The immediate advantage of such a hybrid molecular/VLSI device would arise from the possible information storage density. The prospect of considerable savings of energy per bit processed also exists. This molecular shift register memory element design solves the conceptual problems associated with integrating molecular size components with larger (micron) size features on a chip.

  5. Breech at term--mode of delivery? A register-based study

    DEFF Research Database (Denmark)

    Krebs, L; Langhoff-Roos, J; Weber, Tom

    1995-01-01

    . Register-based cohort study of all (n = 15718) singleton term breech deliveries of non-malformed infants in Denmark 1982-1990. Process and outcome measures: mode of delivery, gestational age, birth weight, congenital malformations, intrapartum death, Apgar scores and early neonatal death. RESULTS. A total...... of 3247 (20.7%) term infants were delivered vaginally, 7106 (45.3%) by elective and 5356 (34.1%) by emergency cesarean section. Infants delivered vaginally and by emergency cesarean section had significantly higher rates of mortality (intrapartum and early neonatal death) and morbidity (low Apgar scores......) when compared to those delivered by elective cesarean section. In vaginal deliveries, parity was not correlated with outcome, but infants with a birth weight above 4000 grams had significantly higher rates of low Apgar scores. CONCLUSIONS. Register data on singleton term breech deliveries imply...

  6. Breech at term--mode of delivery? A register-based study

    DEFF Research Database (Denmark)

    Krebs, L; Langhoff-Roos, J; Weber, Tom

    1995-01-01

    ) when compared to those delivered by elective cesarean section. In vaginal deliveries, parity was not correlated with outcome, but infants with a birth weight above 4000 grams had significantly higher rates of low Apgar scores. CONCLUSIONS. Register data on singleton term breech deliveries imply......BACKGROUND. The present study was designed to determine neonatal mortality and morbidity in non-malformed singleton term infants delivered in breech presentation and identify a possible correlation between outcome on the one hand and mode of delivery, parity and birth weight on the other. METHODS....... Register-based cohort study of all (n = 15718) singleton term breech deliveries of non-malformed infants in Denmark 1982-1990. Process and outcome measures: mode of delivery, gestational age, birth weight, congenital malformations, intrapartum death, Apgar scores and early neonatal death. RESULTS. A total...

  7. Improved land use classification from Landsat and Seasat satellite imagery registered to a common map base

    Science.gov (United States)

    Clark, J.

    1981-01-01

    In the case of Landsat Multispectral Scanner System (MSS) data, ambiguities in spectral signature can arise in urban areas. A study was initiated in the belief that Seasat digital SAR could help provide the spectral separability needed for a more accurate urban land use classification. A description is presented of the results of land use classifications performed on Landsat and preprocessed Seasat imagery that were registered to a common map base. The process of registering imagery and training site boundary coordinates to a common map has been reported by Clark (1980). It is found that preprocessed Seasat imagery provides signatures for urban land uses which are spectrally separable from Landsat signatures. This development appears to significantly improve land use classifications in an urban setting for class 12 (Commercial and Services), class 13 (Industrial), and class 14 (Transportation, Communications, and Utilities).

  8. Dynamics in the quantum/classical limit based on selective use of the quantum potential

    International Nuclear Information System (INIS)

    Garashchuk, Sophya; Dell’Angelo, David; Rassolov, Vitaly A.

    2014-01-01

    A classical limit of quantum dynamics can be defined by compensation of the quantum potential in the time-dependent Schrödinger equation. The quantum potential is a non-local quantity, defined in the trajectory-based form of the Schrödinger equation, due to Madelung, de Broglie, and Bohm, which formally generates the quantum-mechanical features in dynamics. Selective inclusion of the quantum potential for the degrees of freedom deemed “quantum,” defines a hybrid quantum/classical dynamics, appropriate for molecular systems comprised of light and heavy nuclei. The wavefunction is associated with all of the nuclei, and the Ehrenfest, or mean-field, averaging of the force acting on the classical degrees of freedom, typical of the mixed quantum/classical methods, is avoided. The hybrid approach is used to examine evolution of light/heavy systems in the harmonic and double-well potentials, using conventional grid-based and approximate quantum-trajectory time propagation. The approximate quantum force is defined on spatial domains, which removes unphysical coupling of the wavefunction fragments corresponding to distinct classical channels or configurations. The quantum potential, associated with the quantum particle, generates forces acting on both quantum and classical particles to describe the backreaction

  9. Dynamics in the quantum/classical limit based on selective use of the quantum potential

    Energy Technology Data Exchange (ETDEWEB)

    Garashchuk, Sophya, E-mail: garashchuk@sc.edu; Dell’Angelo, David; Rassolov, Vitaly A. [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208 (United States)

    2014-12-21

    A classical limit of quantum dynamics can be defined by compensation of the quantum potential in the time-dependent Schrödinger equation. The quantum potential is a non-local quantity, defined in the trajectory-based form of the Schrödinger equation, due to Madelung, de Broglie, and Bohm, which formally generates the quantum-mechanical features in dynamics. Selective inclusion of the quantum potential for the degrees of freedom deemed “quantum,” defines a hybrid quantum/classical dynamics, appropriate for molecular systems comprised of light and heavy nuclei. The wavefunction is associated with all of the nuclei, and the Ehrenfest, or mean-field, averaging of the force acting on the classical degrees of freedom, typical of the mixed quantum/classical methods, is avoided. The hybrid approach is used to examine evolution of light/heavy systems in the harmonic and double-well potentials, using conventional grid-based and approximate quantum-trajectory time propagation. The approximate quantum force is defined on spatial domains, which removes unphysical coupling of the wavefunction fragments corresponding to distinct classical channels or configurations. The quantum potential, associated with the quantum particle, generates forces acting on both quantum and classical particles to describe the backreaction.

  10. A Quantum Proxy Weak Blind Signature Scheme Based on Controlled Quantum Teleportation

    Science.gov (United States)

    Cao, Hai-Jing; Yu, Yao-Feng; Song, Qin; Gao, Lan-Xiang

    2015-04-01

    Proxy blind signature is applied to the electronic paying system, electronic voting system, mobile agent system, security of internet, etc. A quantum proxy weak blind signature scheme is proposed in this paper. It is based on controlled quantum teleportation. Five-qubit entangled state functions as quantum channel. The scheme uses the physical characteristics of quantum mechanics to implement message blinding, so it could guarantee not only the unconditional security of the scheme but also the anonymity of the messages owner.

  11. Quantum logic gates based on coherent electron transport in quantum wires.

    Science.gov (United States)

    Bertoni, A; Bordone, P; Brunetti, R; Jacoboni, C; Reggiani, S

    2000-06-19

    It is shown that the universal set of quantum logic gates can be realized using solid-state quantum bits based on coherent electron transport in quantum wires. The elementary quantum bits are realized with a proper design of two quantum wires coupled through a potential barrier. Numerical simulations show that (a) a proper design of the coupling barrier allows one to realize any one-qbit rotation and (b) Coulomb interaction between two qbits of this kind allows the implementation of the CNOT gate. These systems are based on a mature technology and seem to be integrable with conventional electronics.

  12. Transitionless quantum driving based wireless power transfer

    OpenAIRE

    Paul, Koushik; Sarma, Amarendra K.

    2017-01-01

    Shortcut to adiabaticity (STA) techniques have the potential to drive a system beyond the adiabatic limits. Here, we present a robust and efficient method for wireless power transfer (WPT) between two coils based on the so-called transitionless quantum driving (TQD) algorithm. We show that it is possible to transfer power between the coils significantly fast compared to its adiabatic counterpart. The scheme is fairly robust against the variations in the coupling strength and the coupling dist...

  13. Quantum size effect and thermal stability of carbon-nanotube-based quantum dot

    International Nuclear Information System (INIS)

    Huang, N.Y.; Peng, J.; Liang, S.D.; Li, Z.B.; Xu, N.S.

    2004-01-01

    Full text: Based on semi-experience quantum chemical calculation, we have investigated the quantum size effect and thermal stability of open-end carbon nanotube (5, 5) quantum dots of 20 to 400 atoms. It was found that there is a gap in the energy band of all carbon nanotube (5, 5) quantum dots although a (5, 5) carbon nanotube is metallic. The energy gap of quantum dots is much dependent of the number of atoms in a dot, as a result of the quantization rules imposed by the finite scales in both radial and axial directions of a carbon nanotube quantum dot. Also, the heat of formation of carbon nanotube quantum dots is dependent of the size of a quantum dot. (author)

  14. Quantum process reconstruction based on mutually unbiased basis

    International Nuclear Information System (INIS)

    Fernandez-Perez, A.; Saavedra, C.; Klimov, A. B.

    2011-01-01

    We study a quantum process reconstruction based on the use of mutually unbiased projectors (MUB projectors) as input states for a D-dimensional quantum system, with D being a power of a prime number. This approach connects the results of quantum-state tomography using mutually unbiased bases with the coefficients of a quantum process, expanded in terms of MUB projectors. We also study the performance of the reconstruction scheme against random errors when measuring probabilities at the MUB projectors.

  15. Quantum Ensemble Classification: A Sampling-Based Learning Control Approach.

    Science.gov (United States)

    Chen, Chunlin; Dong, Daoyi; Qi, Bo; Petersen, Ian R; Rabitz, Herschel

    2017-06-01

    Quantum ensemble classification (QEC) has significant applications in discrimination of atoms (or molecules), separation of isotopes, and quantum information extraction. However, quantum mechanics forbids deterministic discrimination among nonorthogonal states. The classification of inhomogeneous quantum ensembles is very challenging, since there exist variations in the parameters characterizing the members within different classes. In this paper, we recast QEC as a supervised quantum learning problem. A systematic classification methodology is presented by using a sampling-based learning control (SLC) approach for quantum discrimination. The classification task is accomplished via simultaneously steering members belonging to different classes to their corresponding target states (e.g., mutually orthogonal states). First, a new discrimination method is proposed for two similar quantum systems. Then, an SLC method is presented for QEC. Numerical results demonstrate the effectiveness of the proposed approach for the binary classification of two-level quantum ensembles and the multiclass classification of multilevel quantum ensembles.

  16. Migration and health: exploring the role of migrant status through register-based studies.

    Science.gov (United States)

    Nørredam, Marie

    2015-04-01

    This thesis aims to explore migrant status as a determinant in register-based studies on migrant health. It is based on eight studies that investigate the following three main issues: 1) What is the importance of migrant status for morbidity patterns among migrants compared with Native Danes? 2) Do migrant status and ethnicity affect clinical indicators of access among migrants compared with native Danes? 3) What is the importance of migrant status for mortality patterns among migrants compared with Native Danes? The thesis builds on a register-based historical prospective cohort design. Through Statistics Denmark, all refugees (n = 29,174) and family reunification immigrants (n = 33,287) who received residence permits in Denmark from 1 January 1993 to 31 December 1999 were included and matched 4:1 on age and sex with Native Danes. Register linkage was obtained twice during follow-ups in 2004 and 2008 respectively. Personal identification numbers were cross-linked to the Danish Psychiatric Central Register, the National Patient Registry, the Registry of Coercive Measures in Psychiatric Treatment, the Register of Causes of Death, and the Danish Cancer Registry. Migrant status defined by legal grounds for obtaining a residence permit was dichotomised into refugees and family reunification immigrants and used as the determinant in most studies. Analyses involved both Poisson and Cox regression analysis. Most analyses were stratified by ethnicity and adjusted for age and sex. Some were also stratified for individual income. Three sub-themes were investigated: morbidity, clinical indicators of access, and mortality. The first sub-theme (Papers I-III) showed that refugees had a consistently higher morbidity from several mental health disorders in contrast to family reunification immigrants, whose morbidity from mental disorders was lower than or similar to native Danes. The cancer incidence study did not find an effect of migrant status but found, rather, that migrants

  17. Non-hospital based registered nurses and the risk of bloodborne pathogen exposure.

    Science.gov (United States)

    Gershon, Robyn R M; Qureshi, Kristine A; Pogorzelska, Monika; Rosen, Jonathan; Gebbie, Kristine M; Brandt-Rauf, Paul W; Sherman, Martin F

    2007-10-01

    The aim of this study was to assess the risk of blood and body fluid exposure among non-hospital based registered nurses (RNs) employed in New York State. The study population was mainly unionized public sector workers, employed in state institutions. A self-administered questionnaire was completed by a random stratified sample of members of the New York State Nurses Association and registered nurse members of the New York State Public Employees Federation. Results were reviewed by participatory action research (PAR) teams to identify opportunities for improvement. Nine percent of respondents reported at least one needlestick injury in the 12-month period prior to the study. The percutaneous injury (PI) rate was 13.8 per 100 person years. Under-reporting was common; 49% of all PIs were never formally reported and 70% never received any post-exposure care. Primary reasons for not reporting included: time constraints, fear, and lack of information on reporting. Significant correlates of needlestick injuries included tenure, patient load, hours worked, lack of compliance with standard precautions, handling needles and other sharps, poor safety climate, and inadequate training and availability of safety devices (prisk reduction strategies, with an emphasis on safety devices. Non-hospital based RNs are at risk for bloodborne exposure at rates comparable to hospital based RNs; underreporting is an important obstacle to infection prevention, and primary and secondary risk management strategies appeared to be poorly implemented. Intervention research is warranted to evaluate improved risk reduction practices tailored to this population of RNs.

  18. Decoherence and Entanglement Simulation in a Model of Quantum Neural Network Based on Quantum Dots

    Directory of Open Access Journals (Sweden)

    Altaisky Mikhail V.

    2016-01-01

    Full Text Available We present the results of the simulation of a quantum neural network based on quantum dots using numerical method of path integral calculation. In the proposed implementation of the quantum neural network using an array of single-electron quantum dots with dipole-dipole interaction, the coherence is shown to survive up to 0.1 nanosecond in time and up to the liquid nitrogen temperature of 77K.We study the quantum correlations between the quantum dots by means of calculation of the entanglement of formation in a pair of quantum dots on the GaAs based substrate with dot size of 100 ÷ 101 nanometer and interdot distance of 101 ÷ 102 nanometers order.

  19. Quantum networks based on spins in diamond

    International Nuclear Information System (INIS)

    Ronald Hanson

    2014-01-01

    Entanglement of spatially separated objects is one of the most intriguing phenomena that can occur in physics. Besides being of fundamental interest, entanglement is also a valuable resource in quantum information technology enabling secure quantum communication networks and distributed quantum computing. Here we present our most recent results towards the realization of scalable quantum networks with solid-state qubits. (author)

  20. Bright infrared LEDs based on colloidal quantum-dots

    KAUST Repository

    Sun, Liangfeng; Choi, Joshua J.; Stachnik, David; Bartnik, Adam C.; Hyun, Byung-Ryool; Malliaras, George G.; Hanrath, Tobias; Wise, Frank W.

    2013-01-01

    Record-brightness infrared LEDs based on colloidal quantum-dots have been achieved through control of the spacing between adjacent quantum-dots. By tuning the size of quantum-dots, the emission wavelengths can be tuned between 900nm and 1650nm. © 2013 Materials Research Society.

  1. Multiparty secret sharing of quantum information based on entanglement swapping

    International Nuclear Information System (INIS)

    Li Yongmin; Zhang Kuanshou; Peng Kunchi

    2004-01-01

    A protocol of multiparty secret sharing of quantum information based on entanglement swapping is analyzed. In this protocol, Bell states are needed in order to realize the quantum information secret sharing and it is convenient to realize the quantum secret sharing among the members of any subset of users

  2. Efficient multiuser quantum cryptography network based on entanglement.

    Science.gov (United States)

    Xue, Peng; Wang, Kunkun; Wang, Xiaoping

    2017-04-04

    We present an efficient quantum key distribution protocol with a certain entangled state to solve a special cryptographic task. Also, we provide a proof of security of this protocol by generalizing the proof of modified of Lo-Chau scheme. Based on this two-user scheme, a quantum cryptography network protocol is proposed without any quantum memory.

  3. Position-based quantum cryptography and catalytic computation

    NARCIS (Netherlands)

    Speelman, F.

    2016-01-01

    In this thesis, we present several results along two different lines of research. The first part concerns the study of position-based quantum cryptography, a topic in quantum cryptography. By combining quantum mechanics with special relativity theory, new cryptographic tasks can be developed that

  4. The Register-based Census in Germany: Historical Context and Relevance for Population Research

    Directory of Open Access Journals (Sweden)

    Rembrandt Scholz

    2016-08-01

    Full Text Available In 2011, Germany carried out its first census after a 20-year break. In light of the United Nations’ recommendations that countries initiate a population census at least every 10 years, the census was long overdue. Moreover, demographers had for some time been demanding a new enumeration that would enable them to place the calculation of demographic indicators on a reliable basis. With the 2011 census, Germany not only met the demand for a current population census, but also broke new ground by using a register-based approach. Unlike the Scandinavian countries, which have a long tradition of performing register-based data analyses, the linking of administrative data in Germany is restricted by the country’s legal framework. Thus, the 2011 census was an ambitious project. After contextualising the 2011 census historically, we discuss in this contribution the census’ relevance for generating central demographic data. Specifically, we compare the updated population estimates of the 1987 census to the results of the 2011 census in order to identify possible systematic sources of error that distort demographic indicators and analyses.

  5. High agreement between the new Mongolian electronic immunization register and written immunization records: a health centre based audit

    Directory of Open Access Journals (Sweden)

    Jocelyn Chan

    2017-09-01

    Full Text Available Introduction: Monitoring of vaccination coverage is vital for the prevention and control of vaccine-preventable diseases. Electronic immunization registers have been increasingly adopted to assist with the monitoring of vaccine coverage; however, there is limited literature about the use of electronic registers in low- and middle-income countries such as Mongolia. We aimed to determine the accuracy and completeness of the newly introduced electronic immunization register for calculating vaccination coverage and determining vaccine effectiveness within two districts in Mongolia in comparison to written health provider records. Methods: We conducted a cross-sectional record review among children 2–23 months of age vaccinated at immunization clinics within the two districts. We linked data from written records with the electronic immunization register using the national identification number to determine the completeness and accuracy of the electronic register. Results: Both completeness (90.9%; 95% CI: 88.4–93.4 and accuracy (93.3%; 95% CI: 84.1–97.4 of the electronic immunization register were high when compared to written records. The increase in completeness over time indicated a delay in data entry. Conclusion: Through this audit, we have demonstrated concordance between a newly introduced electronic register and health provider records in a middle-income country setting. Based on this experience, we recommend that electronic registers be accompanied by routine quality assurance procedures for the monitoring of vaccination programmes in such settings.

  6. Cohort Profile: the National Prostate Cancer Register of Sweden and Prostate Cancer data Base Sweden 2.0.

    Science.gov (United States)

    Van Hemelrijck, Mieke; Wigertz, Annette; Sandin, Fredrik; Garmo, Hans; Hellström, Karin; Fransson, Per; Widmark, Anders; Lambe, Mats; Adolfsson, Jan; Varenhorst, Eberhard; Johansson, Jan-Erik; Stattin, Pär

    2013-08-01

    In 1987, the first Regional Prostate Cancer Register was set up in the South-East health-care region of Sweden. Other health-care regions joined and since 1998 virtually all prostate cancer (PCa) cases are registered in the National Prostate Cancer Register (NPCR) of Sweden to provide data for quality assurance, bench marking and clinical research. NPCR includes data on tumour stage, Gleason score, serum level of prostate-specific antigen (PSA) and primary treatment. In 2008, the NPCR was linked to a number of other population-based registers by use of the personal identity number. This database named Prostate Cancer data Base Sweden (PCBaSe) has now been extended with more cases, longer follow-up and a selection of two control series of men free of PCa at the time of sampling, as well as information on brothers of men diagnosed with PCa, resulting in PCBaSe 2.0. This extension allows for studies with case-control, cohort or longitudinal case-only design on aetiological factors, pharmaceutical prescriptions and assessment of long-term outcomes. The NPCR covers >96% of all incident PCa cases registered by the Swedish Cancer Register, which has an underreporting of <3.7%. The NPCR is used to assess trends in incidence, treatment and outcome of men with PCa. Since the national registers linked to PCBaSe are complete, studies from PCBaSe 2.0 are truly population based.

  7. Quantum random number generator based on quantum tunneling effect

    OpenAIRE

    Zhou, Haihan; Li, Junlin; Pan, Dong; Zhang, Weixing; Long, Guilu

    2017-01-01

    In this paper, we proposed an experimental implementation of quantum random number generator(QRNG) with inherent randomness of quantum tunneling effect of electrons. We exploited InGaAs/InP diodes, whose valance band and conduction band shared a quasi-constant energy barrier. We applied a bias voltage on the InGaAs/InP avalanche diode, which made the diode works under Geiger mode, and triggered the tunneling events with a periodic pulse. Finally, after data collection and post-processing, our...

  8. Indicators of fetal growth and bipolar disorder: a Danish national register-based study

    DEFF Research Database (Denmark)

    Øgendahl, Bettina; Agerbo, Esben; Byrne, Majella

    2006-01-01

    contradictory. The aim of this study was to investigate whether the risk of bipolar disorder is associated with exposure to indicators of fetal growth.Method. A national population nested case-control study based on Danish longitudinal register databases was carried out. Conditional logistic regression was used......, controlling for potential confounding factors such as parental age at birth, socio-economic indicators and psychiatric history. We identified 196 cases, and each case was time-, age- and sex-matched with 25 normal population-based controls. All cases were between the ages of 12 and 26 years at the time......Background. Several studies have found an association between indicators of fetal growth and/or obstetric complications and schizophrenia but only a few studies have investigated the possible association between these factors and bipolar disorder. Furthermore, the results of these studies have been...

  9. Orthonormal Wavelet Bases for Quantum Molecular Dynamics

    International Nuclear Information System (INIS)

    Tymczak, C.; Wang, X.

    1997-01-01

    We report on the use of compactly supported, orthonormal wavelet bases for quantum molecular-dynamics (Car-Parrinello) algorithms. A wavelet selection scheme is developed and tested for prototypical problems, such as the three-dimensional harmonic oscillator, the hydrogen atom, and the local density approximation to atomic and molecular systems. Our method shows systematic convergence with increased grid size, along with improvement on compression rates, thereby yielding an optimal grid for self-consistent electronic structure calculations. copyright 1997 The American Physical Society

  10. Threshold quantum cryptograph based on Grover's algorithm

    International Nuclear Information System (INIS)

    Du Jianzhong; Qin Sujuan; Wen Qiaoyan; Zhu Fuchen

    2007-01-01

    We propose a threshold quantum protocol based on Grover's operator and permutation operator on one two-qubit signal. The protocol is secure because the dishonest parties can only extract 2 bits from 3 bits information of operation on one two-qubit signal while they have to introduce error probability 3/8. The protocol includes a detection scheme to resist Trojan horse attack. With probability 1/2, the detection scheme can detect a multi-qubit signal that is used to replace a single-qubit signal, while it makes every legitimate qubit invariant

  11. Wavelet-Based Quantum Field Theory

    Directory of Open Access Journals (Sweden)

    Mikhail V. Altaisky

    2007-11-01

    Full Text Available The Euclidean quantum field theory for the fields $phi_{Delta x}(x$, which depend on both the position $x$ and the resolution $Delta x$, constructed in SIGMA 2 (2006, 046, on the base of the continuous wavelet transform, is considered. The Feynman diagrams in such a theory become finite under the assumption there should be no scales in internal lines smaller than the minimal of scales of external lines. This regularisation agrees with the existing calculations of radiative corrections to the electron magnetic moment. The transition from the newly constructed theory to a standard Euclidean field theory is achieved by integration over the scale arguments.

  12. Quantum BCH Codes Based on Spectral Techniques

    International Nuclear Information System (INIS)

    Guo Ying; Zeng Guihua

    2006-01-01

    When the time variable in quantum signal processing is discrete, the Fourier transform exists on the vector space of n-tuples over the Galois field F 2 , which plays an important role in the investigation of quantum signals. By using Fourier transforms, the idea of quantum coding theory can be described in a setting that is much different from that seen that far. Quantum BCH codes can be defined as codes whose quantum states have certain specified consecutive spectral components equal to zero and the error-correcting ability is also described by the number of the consecutive zeros. Moreover, the decoding of quantum codes can be described spectrally with more efficiency.

  13. Quantum computing based on space states without charge transfer

    International Nuclear Information System (INIS)

    Vyurkov, V.; Filippov, S.; Gorelik, L.

    2010-01-01

    An implementation of a quantum computer based on space states in double quantum dots is discussed. There is no charge transfer in qubits during a calculation, therefore, uncontrolled entanglement between qubits due to long-range Coulomb interaction is suppressed. Encoding and processing of quantum information is merely performed on symmetric and antisymmetric states of the electron in double quantum dots. Other plausible sources of decoherence caused by interaction with phonons and gates could be substantially suppressed in the structure as well. We also demonstrate how all necessary quantum logic operations, initialization, writing, and read-out could be carried out in the computer.

  14. Fertility treatment and risk of childhood and adolescent mental disorders: register based cohort study.

    Science.gov (United States)

    Bay, Bjørn; Mortensen, Erik Lykke; Hvidtjørn, Dorte; Kesmodel, Ulrik Schiøler

    2013-07-05

    To assess the mental health of children born after fertility treatment by comparing their risk of mental disorders with that of spontaneously conceived children. Prospective register based cohort study. Nationwide register based information from Danish National Health Registers cross linked by a unique personal identification number assigned to all citizens in Denmark. All children born in Denmark in 1995-2003 with follow-up in 2012 when the children were aged 8-17; 33,139 children were conceived after fertility treatment and 555,828 children were born after spontaneous conception. Absolute risks and hazard ratios for overall and specific mental disorders estimated with adjustment for potential confounding variables. Estimated association between the risk of mental disorders and subtypes of procedures, hormone treatments, gamete types, and cause of infertility. The risk of mental disorders in children born after in vitro fertilisation or intracytoplasmic sperm injection was low, and was no higher than in spontaneously conceived children, except for a borderline significant increased risk of tic disorders (hazard ratio 1.40, 95% confidence interval 1.01 to 1.95; absolute risk 0.3%). In contrast, children born after ovulation induction with or without insemination had low but significantly increased risks of any mental disorder (1.20, 1.11 to 1.31; absolute risk 4.1%), autism spectrum disorders (1.20, 1.05 to 1.37; 1.5%), hyperkinetic disorders (1.23, 1.08 to 1.40; 1.7%), conduct, emotional, or social disorder (1.21, 1.02 to 1.45; 0.8%), and tic disorders (1.51, 1.16 to 1.96; 0.4%). There was no risk systematically related to any specific type of hormone drug treatment. There was a small increase in the incidence of mental disorders in children born after ovulation induction/intrauterine insemination. Children born after in vitro fertilisation/intracytoplasmic sperm injection were found to have overall risk comparable with children conceived spontaneously.

  15. Night work, long work weeks, and risk of accidental injuries. A register-based study

    DEFF Research Database (Denmark)

    Larsen, Ann D; Hannerz, Harald; Møller, Simone V

    2017-01-01

    of the European Labour Force Survey from 1999-2013. The current study was based on 150 438 participants (53% men and 47% women). Data on accidental injuries were obtained at individual level from national health registers. We included all 20-59-year-old employees working ≥32 hours a week at the time...... of the interview. We used Poisson regression to estimate the relative rates (RR) of accidental injuries as a function of night work or long work weeks (>40 hours per week) adjusted for year of interview, sex, age, socioeconomic status (SES), industry, and weekly working hours or night work. Age, sex and SES were....... No associations were found between long work weeks (>40 hours) and accidental injuries. Conclusion: We found a modest increased risk of accidental injuries when reporting night work. No associations between long work weeks and risk of accidental injuries were observed. Age, sex and SES showed no trends when...

  16. Obstetric conditions and risk of first admission with schizophrenia: A Danish national register based study

    DEFF Research Database (Denmark)

    Byrne, Majella; Agerbo, Esben; Bennedsen, Birgit

    2007-01-01

    and 24, 826 individually matched controls. Adjusting for the other obstetric factors, family psychiatric history, and socio-economic and demographic factors, risk of schizophrenia was associated with maternal non-attendance at antenatal appointments (Incidence Rate Ratio (IRR) 2.08, 95% CI: 1.0, 4...... (IRR 2.15, 95% CI: 1.1, 4.4), and maternal sepsis of childbirth and the puerperium (IRR 2.91, 95% CI: 1.1, 7.9). There was no significant interaction between the obstetric factors and either sex or family psychiatric history. The data suggest a modest association between prematurity, indicators......-control study based on Danish longitudinal registers was conducted to investigate the risk of schizophrenia associated with exposure to a range of obstetric events. The sample included 1039 first admissions to, or contacts with Danish psychiatric services with an ICD-8 or ICD-10 diagnosis of schizophrenia...

  17. Greenlandic adoptees' psychiatric inpatient contact. A comparative register-based study

    DEFF Research Database (Denmark)

    Laubjerg, Merete; Petersson, Birgit

    2010-01-01

      The aim is to highlight adoptees' and stepchildren's psychiatric contact and diagnoses compared to non-adoptees. The setting is Greenland and the methodology is a comparative in-ward patient register-based study. The background is the Greenlandic tradition for adoption and community child care...... and international research stressing that adoptees demonstrate reverse health outcomes. The cohort is in-ward patients (> 24 hours), born between 1973 and 2005. Correlation between various dependent and independent variables are analysed. The research makes different comparative statements of psychiatric admissions...... and diagnoses related to adoptees and stepchildren compared to non-adoptees with respect to demographic and socio-economic indicators. The psychiatric data material is collected from 1992 to 2008 and the socio-economic indicators are included from 1996. The findings show, contrary to findings related...

  18. Twin-singleton differences in intelligence: a register-based birth cohort study of Norwegian males.

    Science.gov (United States)

    Eriksen, Willy; Sundet, Jon M; Tambs, Kristian

    2012-10-01

    The aim was to determine the difference in intelligence between singletons and twins in young adulthood. Data from the Medical Birth Register of Norway were linked with register data from the Norwegian National Conscript Service. The study base consisted of data on the 445,463 males who were born alive in either single or twin births in Norway during 1967-1984 and who were examined at the time of the mandatory military conscription (age 18-20). Within this study base, there were data on 1,653 sibships of full brothers that included at least one man born in single birth and at least one man born in twin birth (4,307 persons, including 2,378 twins and 1,929 singletons). The intelligence scores of the singletons were 11% (95% confidence interval [CI]: 9-14%) of a standard deviation higher than those of the twins, after adjustment for birth year, birth order, parental ages at delivery, parental education levels, and other factors. The adjusted within-family difference was also 11% (95 % CI: 6-16%) of a standard deviation, indicating that unmeasured factors shared by siblings (e.g., maternal body height) have not influenced the estimate in important ways. When gestational age at birth was added to the model, the estimate for the difference in intelligence score was approximately the same. Including birth weight in the model strongly reduced the estimate. In conclusion, twins born in Norway during 1967-1984 had slightly lower intelligence in early adulthood compared with the singletons.

  19. Upconversion-based receivers for quantum hacking-resistant quantum key distribution

    Science.gov (United States)

    Jain, Nitin; Kanter, Gregory S.

    2016-07-01

    We propose a novel upconversion (sum frequency generation)-based quantum-optical system design that can be employed as a receiver (Bob) in practical quantum key distribution systems. The pump governing the upconversion process is produced and utilized inside the physical receiver, making its access or control unrealistic for an external adversary (Eve). This pump facilitates several properties which permit Bob to define and control the modes that can participate in the quantum measurement. Furthermore, by manipulating and monitoring the characteristics of the pump pulses, Bob can detect a wide range of quantum hacking attacks launched by Eve.

  20. Quantum physics an introduction based on photons

    CERN Document Server

    Lvovsky, A I

    2018-01-01

    This textbook is intended to accompany a two-semester course on quantum mechanics for physics students. Along with the traditional material covered in such a course (states, operators, Schrödinger equation, hydrogen atom), it offers in-depth discussion of the Hilbert space, the nature of measurement, entanglement, and decoherence – concepts that are crucial for the understanding of quantum physics and its relation to the macroscopic world, but rarely covered in entry-level textbooks. The book uses a mathematically simple physical system – photon polarization – as the visualization tool, permitting the student to see the entangled beauty of the quantum world from the very first pages. The formal concepts of quantum physics are illustrated by examples from the forefront of modern quantum research, such as quantum communication, teleportation and nonlocality. The author adopts a Socratic pedagogy: The student is guided to develop the machinery of quantum physics independently by solving sets of carefully ...

  1. Experimental quantum ratchets based on nanostructures

    International Nuclear Information System (INIS)

    Linke, H.; Loefgren, A.; Sheng, W.; Xu, H.; Svensson, A.; Omling, P.; Lindelof, P.E.

    1999-01-01

    Full text: A number of biological processes, for instance muscular contraction and intracellular transport, are based on a fascinating physical principle: In periodic, asymmetric potentials, so-called ratchets, the random motion of Brownian particles can be put to use by extracting energy from nonequilibrium fluctuations. These findings have recently revived interest in physics to explore the general principles of ratchet effects. So far, most ratchet systems studied assumed or used classical systems. In extension of this previous work, highly interesting and new physics can also be expected from ratchet mechanisms that rely on quantum processes. In this contribution, the requirements for experimental studies of quantum ratchet effects will be discussed, and it will be pointed out that these prerequisites are ideally fulfilled in semiconductor- and metal-nanostructures. As an example, experimental and theoretical results will be presented showing that phase-coherent, asymmetric (triangular) electron cavities can partially rectify an applied AC voltage. Using this effect, which is related to electron wave interference, an electron current can be generated without applied net field

  2. Quantum cosmology based on discrete Feynman paths

    International Nuclear Information System (INIS)

    Chew, Geoffrey F.

    2002-01-01

    Although the rules for interpreting local quantum theory imply discretization of process, Lorentz covariance is usually regarded as precluding time quantization. Nevertheless a time-discretized quantum representation of redshifting spatially-homogeneous universe may be based on discrete-step Feynman paths carrying causal Lorentz-invariant action--paths that not only propagate the wave function but provide a phenomenologically-promising elementary-particle Hilbert-space basis. In a model under development, local path steps are at Planck scale while, at a much larger ''wave-function scale'', global steps separate successive wave-functions. Wave-function spacetime is but a tiny fraction of path spacetime. Electromagnetic and gravitational actions are ''at a distance'' in Wheeler-Feynman sense while strong (color) and weak (isospin) actions, as well as action of particle motion, are ''local'' in a sense paralleling the action of local field theory. ''Nonmaterial'' path segments and ''trivial events'' collaborate to define energy and gravity. Photons coupled to conserved electric charge enjoy privileged model status among elementary fermions and vector bosons. Although real path parameters provide no immediate meaning for ''measurement'', the phase of the complex wave function allows significance for ''information'' accumulated through ''gentle'' electromagnetic events involving charged matter and ''soft'' photons. Through its soft-photon content the wave function is an ''information reservoir''

  3. Registered partnerships

    CERN Multimedia

    Staff Association

    2015-01-01

    In recent decades, family patterns have changed significantly. National laws have taken these changes into account, recognizing new forms of unions, different to heterosexual marriage. Indeed, recently some countries have given the possibility to same-sex couples to enter into various forms of unions. Staff regulations of international organizations are not directly affected by national laws, but in the context of diversity policies, the lack of recognition of these new forms of unions, may appear to discriminate based on sexual orientation and to limit the freedom of choosing marital status. A study by the International Service for Remunerations and Pensions (iSRP) of the OECD in January 2015 (PROS Report (1015) 04) shows that in comparison with other international organizations, CERN offers the least favorable social conditions for its Staff with in a registered partnership. As part of the Five-year review in 2015, it is important that CERN aligns itself with the practice of these other organizations...

  4. A register-based study of the antimicrobial usage in Danish veal calves and young bulls

    DEFF Research Database (Denmark)

    Fertner, Mette Ely; Toft, Nils; Martin, Henrik Læssøe

    2016-01-01

    High antimicrobial usage and multidrug resistance have been reported in veal calves in Europe. This may be attributed to a high risk of disease as veal calves are often purchased from numerous dairy herds, exposed to stress related to the transport and commingling of new animals, and fed a new...... ration. In this study, we used national register data to characterize the use of antimicrobials registered for large Danish veal calf and young bull producing herds in 2014. A total of 325 herds with veal calf and potentially young bull production were identified from the Danish Cattle database....... According to the national Danish database on drugs for veterinary use (VetStat), a total of 537,399 Animal Daily Doses (ADD200) were registered for these 325 herds during 2014. The amount of antimicrobials registered in 2014 varied throughout the year, with the highest amounts registered in autumn...

  5. Blind topological measurement-based quantum computation.

    Science.gov (United States)

    Morimae, Tomoyuki; Fujii, Keisuke

    2012-01-01

    Blind quantum computation is a novel secure quantum-computing protocol that enables Alice, who does not have sufficient quantum technology at her disposal, to delegate her quantum computation to Bob, who has a fully fledged quantum computer, in such a way that Bob cannot learn anything about Alice's input, output and algorithm. A recent proof-of-principle experiment demonstrating blind quantum computation in an optical system has raised new challenges regarding the scalability of blind quantum computation in realistic noisy conditions. Here we show that fault-tolerant blind quantum computation is possible in a topologically protected manner using the Raussendorf-Harrington-Goyal scheme. The error threshold of our scheme is 4.3 × 10(-3), which is comparable to that (7.5 × 10(-3)) of non-blind topological quantum computation. As the error per gate of the order 10(-3) was already achieved in some experimental systems, our result implies that secure cloud quantum computation is within reach.

  6. Quantum multi-signature protocol based on teleportation

    International Nuclear Information System (INIS)

    Wen Xiao-jun; Liu Yun; Sun Yu

    2007-01-01

    In this paper, a protocol which can be used in multi-user quantum signature is proposed. The scheme of signature and verification is based on the correlation of Greenberger-Horne-Zeilinger (GHZ) states and the controlled quantum teleportation. Different from the digital signatures, which are based on computational complexity, the proposed protocol has perfect security in the noiseless quantum channels. Compared to previous quantum signature schemes, this protocol can verify the signature independent of an arbitrator as well as realize multi-user signature together. (orig.)

  7. A Novel Quantum Video Steganography Protocol with Large Payload Based on MCQI Quantum Video

    Science.gov (United States)

    Qu, Zhiguo; Chen, Siyi; Ji, Sai

    2017-11-01

    As one of important multimedia forms in quantum network, quantum video attracts more and more attention of experts and scholars in the world. A secure quantum video steganography protocol with large payload based on the video strip encoding method called as MCQI (Multi-Channel Quantum Images) is proposed in this paper. The new protocol randomly embeds the secret information with the form of quantum video into quantum carrier video on the basis of unique features of video frames. It exploits to embed quantum video as secret information for covert communication. As a result, its capacity are greatly expanded compared with the previous quantum steganography achievements. Meanwhile, the new protocol also achieves good security and imperceptibility by virtue of the randomization of embedding positions and efficient use of redundant frames. Furthermore, the receiver enables to extract secret information from stego video without retaining the original carrier video, and restore the original quantum video as a follow. The simulation and experiment results prove that the algorithm not only has good imperceptibility, high security, but also has large payload.

  8. Bit-commitment-based quantum coin flipping

    International Nuclear Information System (INIS)

    Nayak, Ashwin; Shor, Peter

    2003-01-01

    In this paper we focus on a special framework for quantum coin-flipping protocols, bit-commitment-based protocols, within which almost all known protocols fit. We show a lower bound of 1/16 for the bias in any such protocol. We also analyze a sequence of multiround protocols that tries to overcome the drawbacks of the previously proposed protocols in order to lower the bias. We show an intricate cheating strategy for this sequence, which leads to a bias of 1/4. This indicates that a bias of 1/4 might be optimal in such protocols, and also demonstrates that a more clever proof technique may be required to show this optimality

  9. Balanced Bipartite Graph Based Register Allocation for Network Processors in Mobile and Wireless Networks

    Directory of Open Access Journals (Sweden)

    Feilong Tang

    2010-01-01

    Full Text Available Mobile and wireless networks are the integrant infrastructure of mobile and pervasive computing that aims at providing transparent and preferred information and services for people anytime anywhere. In such environments, end-to-end network bandwidth is crucial to improve user's transparent experience when providing on-demand services such as mobile video playing. As a result, powerful computing power is required for networked nodes, especially for routers. General-purpose processors cannot meet such requirements due to their limited processing ability, and poor programmability and scalability. Intel's network processor IXP is specially designed for fast packet processing to achieve a broad bandwidth. IXP provides a large number of registers to reduce the number of memory accesses. Registers in an IXP are physically partitioned as two banks so that two source operands in an instruction have to come from the two banks respectively, which makes the IXP register allocation tricky and different from conventional ones. In this paper, we investigate an approach for efficiently generating balanced bipartite graph and register allocation algorithms for the dual-bank register allocation in IXPs. The paper presents a graph uniform 2-way partition algorithm (FPT, which provides an optimal solution to the graph partition, and a heuristic algorithm for generating balanced bipartite graph. Finally, we design a framework for IXP register allocation. Experimental results demonstrate the framework and the algorithms are efficient in register allocation for IXP network processors.

  10. Quantum random number generator based on quantum nature of vacuum fluctuations

    Science.gov (United States)

    Ivanova, A. E.; Chivilikhin, S. A.; Gleim, A. V.

    2017-11-01

    Quantum random number generator (QRNG) allows obtaining true random bit sequences. In QRNG based on quantum nature of vacuum, optical beam splitter with two inputs and two outputs is normally used. We compare mathematical descriptions of spatial beam splitter and fiber Y-splitter in the quantum model for QRNG, based on homodyne detection. These descriptions were identical, that allows to use fiber Y-splitters in practical QRNG schemes, simplifying the setup. Also we receive relations between the input radiation and the resulting differential current in homodyne detector. We experimentally demonstrate possibility of true random bits generation by using QRNG based on homodyne detection with Y-splitter.

  11. Color encryption scheme based on adapted quantum logistic map

    Science.gov (United States)

    Zaghloul, Alaa; Zhang, Tiejun; Amin, Mohamed; Abd El-Latif, Ahmed A.

    2014-04-01

    This paper presents a new color image encryption scheme based on quantum chaotic system. In this scheme, a new encryption scheme is accomplished by generating an intermediate chaotic key stream with the help of quantum chaotic logistic map. Then, each pixel is encrypted by the cipher value of the previous pixel and the adapted quantum logistic map. The results show that the proposed scheme has adequate security for the confidentiality of color images.

  12. Ground test of satellite constellation based quantum communication

    OpenAIRE

    Liao, Sheng-Kai; Yong, Hai-Lin; Liu, Chang; Shentu, Guo-Liang; Li, Dong-Dong; Lin, Jin; Dai, Hui; Zhao, Shuang-Qiang; Li, Bo; Guan, Jian-Yu; Chen, Wei; Gong, Yun-Hong; Li, Yang; Lin, Ze-Hong; Pan, Ge-Sheng

    2016-01-01

    Satellite based quantum communication has been proven as a feasible way to achieve global scale quantum communication network. Very recently, a low-Earth-orbit (LEO) satellite has been launched for this purpose. However, with a single satellite, it takes an inefficient 3-day period to provide the worldwide connectivity. On the other hand, similar to how the Iridium system functions in classic communication, satellite constellation (SC) composed of many quantum satellites, could provide global...

  13. A descriptive study of registered nurses' experiences with web-based learning.

    Science.gov (United States)

    Atack, Lynda; Rankin, James

    2002-11-01

    To describe the experiences of registered nurses (RNs) who enrolled in a web-based course from either their home or the workplace. In order to maintain competency in rapidly changing health care systems, and meet the challenge of overcoming traditional barriers to continuing education, RNs need access to innovative educational delivery methods. As yet, little is known about the web-based learners' experience, particularly when courses are accessed from the nursing practice setting. The article focuses on the results from questionnaires conducted with 57 RNs enrolled in a web-based, postdiploma course. These findings emanate from a larger study using survey method and focus group interviews. Nurses' experiences were measured using the Online Learner Support Instrument which was developed and tested for use in the study. Most nurses found the course highly satisfactory. Not all experiences were positive however, and a number of challenges were faced. Access to the course from home was reported as very satisfactory for the majority, while work users encountered a number of serious barriers such as insufficient time and limited computer access. The RNs made significant gains in their learning with e-mail, Internet, keyboarding and word processing skills during the 16-week course. Lack of computer skills, erroneous perceptions of course workload and inadequate preparation for web learning were largely responsible for the majority of withdrawals. Web-based learning can be an effective mode of delivery for nursing education. Advance preparation by educational institutions, employers and prospective students is essential. Teachers, peers, technology, course design and the learning environment are key variables that influence the learners' experience and success.

  14. Compact Interconnection Networks Based on Quantum Dots

    Science.gov (United States)

    Fijany, Amir; Toomarian, Nikzad; Modarress, Katayoon; Spotnitz, Matthew

    2003-01-01

    Architectures that would exploit the distinct characteristics of quantum-dot cellular automata (QCA) have been proposed for digital communication networks that connect advanced digital computing circuits. In comparison with networks of wires in conventional very-large-scale integrated (VLSI) circuitry, the networks according to the proposed architectures would be more compact. The proposed architectures would make it possible to implement complex interconnection schemes that are required for some advanced parallel-computing algorithms and that are difficult (and in many cases impractical) to implement in VLSI circuitry. The difficulty of implementation in VLSI and the major potential advantage afforded by QCA were described previously in Implementing Permutation Matrices by Use of Quantum Dots (NPO-20801), NASA Tech Briefs, Vol. 25, No. 10 (October 2001), page 42. To recapitulate: Wherever two wires in a conventional VLSI circuit cross each other and are required not to be in electrical contact with each other, there must be a layer of electrical insulation between them. This, in turn, makes it necessary to resort to a noncoplanar and possibly a multilayer design, which can be complex, expensive, and even impractical. As a result, much of the cost of designing VLSI circuits is associated with minimization of data routing and assignment of layers to minimize crossing of wires. Heretofore, these considerations have impeded the development of VLSI circuitry to implement complex, advanced interconnection schemes. On the other hand, with suitable design and under suitable operating conditions, QCA-based signal paths can be allowed to cross each other in the same plane without adverse effect. In principle, this characteristic could be exploited to design compact, coplanar, simple (relative to VLSI) QCA-based networks to implement complex, advanced interconnection schemes. The proposed architectures require two advances in QCA-based circuitry beyond basic QCA-based binary

  15. Suicide among immigrant population in Norway: a national register-based study.

    Science.gov (United States)

    Puzo, Q; Mehlum, L; Qin, P

    2017-06-01

    To investigate differences in suicide risk among immigrant population in Norway compared with native Norwegians, with respect to associated country group of origin. Based on the entire national population, a nested case-control design was adopted using Norwegian national longitudinal registers to obtain 23 073 suicide cases having occurred in 1969-2012 and 373 178 controls. Odds ratios (ORs) for suicide were estimated using conditional logistic regression analysis adjusting for socio-economic factors. Compared with native Norwegians, suicide risk was significantly lower in first- and second-generation immigrants but higher in Norwegian-born with one foreign-born parent and foreign-born individuals with at least one Norwegian-born parent. When stratifying data by country group of origin, first-generation immigrants had lower ORs in most of the strata. Subjects born in Asia and in Central and South America with at least one Norwegian-born parent had a significantly higher risk of suicide. The observed results remained mostly unchanged in the analyses controlled for socio-economic status. Suicide risk is lower in first- and second-generation immigrants but higher in subjects born in Norway with one foreign-born parent and those born abroad with at least one Norwegian-born parent, with notable differences by country group of origin. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Experimental eavesdropping based on optimal quantum cloning

    Czech Academy of Sciences Publication Activity Database

    Bartkiewicz, K.; Lemr, K.; Černoch, Antonín; Soubusta, Jan; Miranowicz, A.

    2013-01-01

    Roč. 110, č. 17 (2013), "173601-1"-"173601-5" ISSN 0031-9007 R&D Projects: GA ČR GAP205/12/0382 Institutional support: RVO:68378271 Keywords : quantum cryptography * qubits * eavesdropping * quantum cloning Subject RIV: BH - Optics, Masers, Lasers Impact factor: 7.728, year: 2013

  17. Inequity of access to ACE inhibitors in Swedish heart failure patients: a register-based study

    Science.gov (United States)

    Lindahl, Bertil; Hanning, Marianne; Westerling, Ragnar

    2016-01-01

    Background Several international studies suggest inequity in access to evidence-based heart failure (HF) care. Specifically, studies of ACE inhibitors (ACEIs) point to reduced ACEI access related to female sex, old age and socioeconomic position. Thus far, most studies have either been rather small, lacking diagnostic data, or lacking the possibility to account for several individual-based sociodemographic factors. Our aim was to investigate differences, which could reflect inequity in access to ACEIs based on sex, age, socioeconomic status or immigration status in Swedish patients with HF. Methods Individually linked register data for all Swedish adults hospitalised for HF in 2005–2010 (n=93 258) were analysed by multivariate regression models to assess the independent risk of female sex, high age, low employment status, low income level, low educational level or foreign country of birth, associated with lack of an ACEI dispensation within 1 year of hospitalisation. Adjustment for possible confounding was made for age, comorbidity, Angiotensin receptor blocker therapy, period and follow-up time. Results Analysis revealed an adjusted OR for no ACEI dispensation for women of 1.31 (95% CI 1.27 to 1.35); for the oldest patients of 2.71 (95% CI 2.53 to 2.91); and for unemployed patients of 1.59 (95% CI 1.46 to 1.73). Conclusions Access to ACEI treatment was reduced in women, older patients and unemployed patients. We conclude that access to ACEIs is inequitable among Swedish patients with HF. Future studies should include clinical data, as well as mortality outcomes in different groups. PMID:26261264

  18. Quantum Image Encryption Algorithm Based on Image Correlation Decomposition

    Science.gov (United States)

    Hua, Tianxiang; Chen, Jiamin; Pei, Dongju; Zhang, Wenquan; Zhou, Nanrun

    2015-02-01

    A novel quantum gray-level image encryption and decryption algorithm based on image correlation decomposition is proposed. The correlation among image pixels is established by utilizing the superposition and measurement principle of quantum states. And a whole quantum image is divided into a series of sub-images. These sub-images are stored into a complete binary tree array constructed previously and then randomly performed by one of the operations of quantum random-phase gate, quantum revolving gate and Hadamard transform. The encrypted image can be obtained by superimposing the resulting sub-images with the superposition principle of quantum states. For the encryption algorithm, the keys are the parameters of random phase gate, rotation angle, binary sequence and orthonormal basis states. The security and the computational complexity of the proposed algorithm are analyzed. The proposed encryption algorithm can resist brute force attack due to its very large key space and has lower computational complexity than its classical counterparts.

  19. A novel clustering algorithm based on quantum games

    International Nuclear Information System (INIS)

    Li Qiang; He Yan; Jiang Jingping

    2009-01-01

    Enormous successes have been made by quantum algorithms during the last decade. In this paper, we combine the quantum game with the problem of data clustering, and then develop a quantum-game-based clustering algorithm, in which data points in a dataset are considered as players who can make decisions and implement quantum strategies in quantum games. After each round of a quantum game, each player's expected payoff is calculated. Later, he uses a link-removing-and-rewiring (LRR) function to change his neighbors and adjust the strength of links connecting to them in order to maximize his payoff. Further, algorithms are discussed and analyzed in two cases of strategies, two payoff matrixes and two LRR functions. Consequently, the simulation results have demonstrated that data points in datasets are clustered reasonably and efficiently, and the clustering algorithms have fast rates of convergence. Moreover, the comparison with other algorithms also provides an indication of the effectiveness of the proposed approach.

  20. Quantum key distribution over multicore fiber based on silicon photonics

    DEFF Research Database (Denmark)

    Ding, Yunhong; Bacco, Davide; Dalgaard, Kjeld

    on quantum physics. In order to exchange secure information between users, quantum key distribution (QKD), a branch of Quantum Communications (QCs), provides good prospects for ultimate security based on the laws of quantum mechanics [2–7]. Most of QKD systems are implemented in a point-to-point link using...... generations, to HD-entanglement distribution. Furthermore, MCFs are expected as a good candidate for overcoming the capacity limit of a current optical communication system, as example the record capacity of 661 Tbits/s was obtained last year with a 30-cores fiber [8]. Proof of concept experiment has already...... requirements in terms of key generation are needed. A solution may be represented by new technologies applied to quantum world. In particular multicore fiber (MCF) open a new scenario for quantum communications, from high-dimensional (HD) spatial entanglement generation, to HD QKD and multi-user key...

  1. Silicon CMOS architecture for a spin-based quantum computer.

    Science.gov (United States)

    Veldhorst, M; Eenink, H G J; Yang, C H; Dzurak, A S

    2017-12-15

    Recent advances in quantum error correction codes for fault-tolerant quantum computing and physical realizations of high-fidelity qubits in multiple platforms give promise for the construction of a quantum computer based on millions of interacting qubits. However, the classical-quantum interface remains a nascent field of exploration. Here, we propose an architecture for a silicon-based quantum computer processor based on complementary metal-oxide-semiconductor (CMOS) technology. We show how a transistor-based control circuit together with charge-storage electrodes can be used to operate a dense and scalable two-dimensional qubit system. The qubits are defined by the spin state of a single electron confined in quantum dots, coupled via exchange interactions, controlled using a microwave cavity, and measured via gate-based dispersive readout. We implement a spin qubit surface code, showing the prospects for universal quantum computation. We discuss the challenges and focus areas that need to be addressed, providing a path for large-scale quantum computing.

  2. Das sprachliche Register (Speech Registers)

    Science.gov (United States)

    Hess-Luttich, Ernest W. B.

    1974-01-01

    The linguistic behavior of a given individual varies; he will on different occasions speak (or write) differently according to what may be roughly described as different social situations: he will use a number of different registers. The application of such registers both in the field of text analysis and in the preparation of teaching materials…

  3. Simulation of quantum computation : A deterministic event-based approach

    NARCIS (Netherlands)

    Michielsen, K; De Raedt, K; De Raedt, H

    We demonstrate that locally connected networks of machines that have primitive learning capabilities can be used to perform a deterministic, event-based simulation of quantum computation. We present simulation results for basic quantum operations such as the Hadamard and the controlled-NOT gate, and

  4. Simulation of Quantum Computation : A Deterministic Event-Based Approach

    NARCIS (Netherlands)

    Michielsen, K.; Raedt, K. De; Raedt, H. De

    2005-01-01

    We demonstrate that locally connected networks of machines that have primitive learning capabilities can be used to perform a deterministic, event-based simulation of quantum computation. We present simulation results for basic quantum operations such as the Hadamard and the controlled-NOT gate, and

  5. Night work, long work weeks, and risk of accidental injuries. A register-based study.

    Science.gov (United States)

    Larsen, Ann D; Hannerz, Harald; Møller, Simone V; Dyreborg, Johnny; Bonde, Jens Peter; Hansen, Johnni; Kolstad, Henrik A; Hansen, Åse Marie; Garde, Anne Helene

    2017-11-01

    Objectives The aims of this study were to (i) investigate the association between night work or long work weeks and the risk of accidental injuries and (ii) test if the association is affected by age, sex or socioeconomic status. Methods The study population was drawn from the Danish version of the European Labour Force Survey from 1999-2013. The current study was based on 150 438 participants (53% men and 47% women). Data on accidental injuries were obtained at individual level from national health registers. We included all 20-59-year-old employees working ≥32 hours a week at the time of the interview. We used Poisson regression to estimate the relative rates (RR) of accidental injuries as a function of night work or long work weeks (>40 hours per week) adjusted for year of interview, sex, age, socioeconomic status (SES), industry, and weekly working hours or night work. Age, sex and SES were included as two-way interactions. Results We observed 23 495 cases of accidental injuries based on 273 700 person years at risk. Exposure to night work was statistically significantly associated with accidental injuries (RR 1.11, 99% CI 1.06-1.17) compared to participants with no recent night work. No associations were found between long work weeks (>40 hours) and accidental injuries. Conclusion We found a modest increased risk of accidental injuries when reporting night work. No associations between long work weeks and risk of accidental injuries were observed. Age, sex and SES showed no trends when included as two-way interactions.

  6. Norwegian GPs' participation in multidisciplinary meetings: A register-based study from 2007

    Directory of Open Access Journals (Sweden)

    Gjesdal Sturla

    2010-11-01

    Full Text Available Abstract Background An increasing number of patients with chronic disorders and a more complex health service demand greater interdisciplinary collaboration in Primary Health Care. The aim of this study was therefore to identify factors related to general practitioners (GPs, their list populations and practice municipalities associated with a high rate of GP participation in multidisciplinary meetings (MDMs. Methods A national cross-sectional register-based study of Norwegian general practice was conducted, including data on all GPs in the Regular GP Scheme in 2007 (N = 3179. GPs were grouped into quartiles based on the annual number of MDMs per patient on their list, and the groups were compared using one-way analysis of variance. Binary logistic regression was used to analyse associations between high rates of participation and characteristics of the GP, their list population and practice municipality. Results On average, GPs attended 30 MDMs per year. The majority of the meetings concerned patients in the age groups 20-59 years. Psychological disorders were the motivation for 53% of the meetings. In a multivariate logistic regression model, the following characteristics predicted a high rate of MDM attendance: younger age of the GP, with an OR of 1.6 (95% CI 1.2-2.1 for GPs Conclusions Psychological problems including substance addiction gave grounds for the majority of MDMs. GPs with a high proportion of consultations with such problems also participated more frequently in MDMs. List size was negatively associated with the rate of MDMs, while a more disadvantaged list population was positively associated. Working in smaller organisational units seemed to facilitate cooperation between different professionals. There may be a generation shift towards more frequent participation in interdisciplinary work among younger GPs.

  7. Chemical sensors based on quantum cascade lasers

    Science.gov (United States)

    Tittel, Frank K.; Kosterev, Anatoliy A.; Rochat, Michel; Beck, Mattias; Faist, Jerome

    2002-09-01

    There is an increasing need in many chemical sensing applications ranging from industrial process control to environmental science and medical diagnostics for fast, sensitive, and selective gas detection based on laser spectroscopy. The recent availability of novel pulsed and cw quantum cascade distributed feedback (QC-DFB) lasers as mid-infrared spectroscopic sources address this need. A number of spectroscopic techniques have been demonstrated. For example, the authors have employed QC-DFB lasers for the monitoring and quantification of several trace gases and isotopic species in ambient air at ppmv and ppbv levels by means of direct absorption, wavelength modulation, cavity enhanced and cavity ringdown spectroscopy. In this work, pulsed thermoelectrically cooled QC-DFB lasers operating at ~15.6 μm were characterized for spectroscopic gas sensing applications. A new method for wavelength scanning based on the repetition rate modulation was developed. A non-wavelength-selective pyroelectric detector was incorporated in the gas sensor giving an advantage of room-temperature operation and low cost. Absorption lines of CO2 and H2O were observed in ambient air providing information about the concentration of these species.

  8. Applied research of quantum information based on linear optics

    International Nuclear Information System (INIS)

    Xu, Xiao-Ye

    2016-01-01

    This thesis reports on outstanding work in two main subfields of quantum information science: one involves the quantum measurement problem, and the other concerns quantum simulation. The thesis proposes using a polarization-based displaced Sagnac-type interferometer to achieve partial collapse measurement and its reversal, and presents the first experimental verification of the nonlocality of the partial collapse measurement and its reversal. All of the experiments are carried out in the linear optical system, one of the earliest experimental systems to employ quantum communication and quantum information processing. The thesis argues that quantum measurement can yield quantum entanglement recovery, which is demonstrated by using the frequency freedom to simulate the environment. Based on the weak measurement theory, the author proposes that white light can be used to precisely estimate phase, and effectively demonstrates that the imaginary part of the weak value can be introduced by means of weak measurement evolution. Lastly, a nine-order polarization-based displaced Sagnac-type interferometer employing bulk optics is constructed to perform quantum simulation of the Landau-Zener evolution, and by tuning the system Hamiltonian, the first experiment to research the Kibble-Zurek mechanism in non-equilibrium kinetics processes is carried out in the linear optical system.

  9. A Quantum Cryptography Communication Network Based on Software Defined Network

    Directory of Open Access Journals (Sweden)

    Zhang Hongliang

    2018-01-01

    Full Text Available With the development of the Internet, information security has attracted great attention in today’s society, and quantum cryptography communication network based on quantum key distribution (QKD is a very important part of this field, since the quantum key distribution combined with one-time-pad encryption scheme can guarantee the unconditional security of the information. The secret key generated by quantum key distribution protocols is a very valuable resource, so making full use of key resources is particularly important. Software definition network (SDN is a new type of network architecture, and it separates the control plane and the data plane of network devices through OpenFlow technology, thus it realizes the flexible control of the network resources. In this paper, a quantum cryptography communication network model based on SDN is proposed to realize the flexible control of quantum key resources in the whole cryptography communication network. Moreover, we propose a routing algorithm which takes into account both the hops and the end-to-end availible keys, so that the secret key generated by QKD can be used effectively. We also simulate this quantum cryptography communication network, and the result shows that based on SDN and the proposed routing algorithm the performance of this network is improved since the effective use of the quantum key resources.

  10. Applied research of quantum information based on linear optics

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xiao-Ye

    2016-08-01

    This thesis reports on outstanding work in two main subfields of quantum information science: one involves the quantum measurement problem, and the other concerns quantum simulation. The thesis proposes using a polarization-based displaced Sagnac-type interferometer to achieve partial collapse measurement and its reversal, and presents the first experimental verification of the nonlocality of the partial collapse measurement and its reversal. All of the experiments are carried out in the linear optical system, one of the earliest experimental systems to employ quantum communication and quantum information processing. The thesis argues that quantum measurement can yield quantum entanglement recovery, which is demonstrated by using the frequency freedom to simulate the environment. Based on the weak measurement theory, the author proposes that white light can be used to precisely estimate phase, and effectively demonstrates that the imaginary part of the weak value can be introduced by means of weak measurement evolution. Lastly, a nine-order polarization-based displaced Sagnac-type interferometer employing bulk optics is constructed to perform quantum simulation of the Landau-Zener evolution, and by tuning the system Hamiltonian, the first experiment to research the Kibble-Zurek mechanism in non-equilibrium kinetics processes is carried out in the linear optical system.

  11. Hepatitis C prevalence in Denmark -an estimate based on multiple national registers

    DEFF Research Database (Denmark)

    Christensen, Peer Brehm; Hay, Gordon; Jepsen, Peter

    2012-01-01

    ABSTRACT: BACKGROUND: A national survey for chronic hepatitis C has not been performed in Denmark and the prevalence is unknown. Our aim was to estimate the prevalence of chronic hepatitis C from public registers and the proportion of these patients who received specialized healthcare. METHODS...... by capture-recapture analysis. The population with undiagnosed hepatitis C was derived from the national register of drug users by comparing diagnosed and tested persons. RESULTS: A total of 6,935 patients diagnosed with chronic hepatitis C were identified in the four registers and the estimated population.......37-0.42) of the population over 15 years of age. CONCLUSIONS: The estimated prevalence of chronic hepatitis C in Denmark was 0.38%. Less than half of the patients with chronic hepatitis C in Denmark have been identified and among these patients, one in three has attended specialised care....

  12. Young people’s risk of suicide attempts in relation to parental death: A population-based register study

    DEFF Research Database (Denmark)

    Christiansen, Erik; Jakobsen, Ida Skytte

    2011-01-01

    Background:  The objective of this study was to examine the association between the death of a biological parent and subsequent suicide attempts by young people (aged 10–22 years), and to explore sociodemographic factors as modifying factors in the process. Methods:  The study used a nested case......–control design. The full study population was obtained from the Danish longitudinal registers and included all individuals born between 1983 and 1989 (n = 403,431 individuals). The 3,465 registered suicide attempters from that group were matched with 75,300 population-based control subjects. Potentially...

  13. Arbitrated Quantum Signature with Hamiltonian Algorithm Based on Blind Quantum Computation

    Science.gov (United States)

    Shi, Ronghua; Ding, Wanting; Shi, Jinjing

    2018-03-01

    A novel arbitrated quantum signature (AQS) scheme is proposed motivated by the Hamiltonian algorithm (HA) and blind quantum computation (BQC). The generation and verification of signature algorithm is designed based on HA, which enables the scheme to rely less on computational complexity. It is unnecessary to recover original messages when verifying signatures since the blind quantum computation is applied, which can improve the simplicity and operability of our scheme. It is proved that the scheme can be deployed securely, and the extended AQS has some extensive applications in E-payment system, E-government, E-business, etc.

  14. Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study.

    Science.gov (United States)

    Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

    2014-05-14

    To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Register-based cohort study. Estonia. An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. Birth order and mortality in two ethno-linguistic groups: Register-based evidence from Finland.

    Science.gov (United States)

    Saarela, Jan; Cederström, Agneta; Rostila, Mikael

    2016-06-01

    Previous research has documented an association between birth order and suicide, although no study has examined whether it depends on the cultural context. Our aim was to study the association between birth order and cause-specific mortality in Finland, and whether it varies by ethno-linguistic affiliation. We used data from the Finnish population register, representing a 5% random sample of all Finnish speakers and a 20% random sample of Swedish speakers, who lived in Finland in any year 1987-2011. For each person, there was a link to all children who were alive in 1987. In total, there were 254,059 siblings in 96,387 sibling groups, and 9797 deaths. We used Cox regressions stratified by each siblings group and estimated all-cause and cause-specific mortality risks during the period 1987-2011. In line with previous research from Sweden, deaths from suicide were significantly associated with birth order. As compared to first-born, second-born had a suicide risk of 1.27, third-born of 1.35, and fourth- or higher-born of 1.72, while other causes of death did not display an evident and consistent birth-order pattern. Results for the Finnish-speaking siblings groups were almost identical to those based on both ethno-linguistic groups. In the Swedish-speaking siblings groups, there was no increase in the suicide risk by birth order, but a statistically not significant tendency towards an association with other external causes of death and deaths from cardiovascular diseases. Our findings provided evidence for an association between birth order and suicide among Finnish speakers in Finland, while no such association was found for Swedish speakers, suggesting that the birth order effect might depend on the cultural context. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Disability pension after coronary revascularization: a prospective nationwide register-based Swedish cohort study.

    Science.gov (United States)

    Zetterström, Katharina; Vaez, Marjan; Alexanderson, Kristina; Ivert, Torbjörn; Pehrsson, Kenneth; Hammar, Niklas; Voss, Margaretha

    2015-03-01

    Scientific knowledge on disability pension (DP) after revascularization by coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) is scarce. The aim was to study the incidence of and risk factors for being granted DP in the 5 years following a first CABG or PCI, accounting for socio-demographic and medical factors. This is a nationwide population-based study using Swedish registers including all patients 30-63 years of age (n = 34,643, 16.4% women) who had a first CABG (n = 14,107) or PCI (n = 20,536) during 1994-2003. All were alive and without reintervention 30 days after the procedure and were not on DP or old-age pension. Multivariable adjusted Cox proportional hazard ratios (HR) for DP were estimated with 95% confidence intervals (CI). In 5 years following revascularization, 32.4% had been granted DP and the hazard ratio (HR) was higher in women (HR 1.55, 95% CI 1.48-1.62), and in CABG patients compared with PCI patients (HR 1.35, 95% CI 1.30-1.40). Long-term sick leave in the year before intervention was the strongest predictor for DP following revascularization. After adjustments for socio-demographic factors and sick-leave days in the 12 months before revascularization, HR remained high in all patients with diabetes mellitus regardless of type of revascularization. DP after coronary revascularization was common, especially among women and CABG patients. Most studied medical covariates, including mental and musculoskeletal disorders, were risk factors for future DP, especially long-term sickness absence. © The European Society of Cardiology 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  17. Epidemiology of valvular heart disease in a Swedish nationwide hospital-based register study.

    Science.gov (United States)

    Andell, Pontus; Li, Xinjun; Martinsson, Andreas; Andersson, Charlotte; Stagmo, Martin; Zöller, Bengt; Sundquist, Kristina; Smith, J Gustav

    2017-11-01

    Transitions in the spectrum of valvular heart diseases (VHDs) in developed countries over the 20th century have been reported from clinical case series, but large, contemporary population-based studies are lacking. We used nationwide registers to identify all patients with a first diagnosis of VHD at Swedish hospitals between 2003 and 2010. Age-stratified and sex-stratified incidence of each VHD and adjusted comorbidity profiles were assessed. In the Swedish population (n=10 164 211), the incidence of VHD was 63.9 per 100 000 person-years, with aortic stenosis (AS; 47.2%), mitral regurgitation (MR; 24.2%) and aortic regurgitation (AR; 18.0%) contributing most of the VHD diagnoses. The majority of VHDs were diagnosed in the elderly (68.9% in subjects aged ≥65 years), but pulmonary valve disease incidence peaked in newborns. Incidences of AR, AS and MR were higher in men who were also more frequently diagnosed at an earlier age. Mitral stenosis (MS) incidence was higher in women. Rheumatic fever was rare. Half of AS cases had concomitant atherosclerotic vascular disease (48.4%), whereas concomitant heart failure and atrial fibrillation were common in mitral valve disease and tricuspid regurgitation. Other common comorbidities were thoracic aortic aneurysms in AR (10.3%), autoimmune disorders in MS (24.5%) and abdominal hernias or prolapse in MR (10.7%) and TR (10.3%). Clinically diagnosed VHD was primarily a disease of the elderly. Rheumatic fever was rare in Sweden, but specific VHDs showed a range of different comorbidity profiles . Pronounced sex-specific patterns were observed for AR and MS, for which the mechanisms remain incompletely understood. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Professional Supervision as Storied Experience: Narrative Analysis Findings for Australian-Based Registered Music Therapists.

    Science.gov (United States)

    Kennelly, Jeanette D; Baker, Felicity A; Daveson, Barbara A

    2017-03-01

    Limited research exists to inform a music therapist's supervision story from their pre-professional training to their practice as a professional. Evidence is needed to understand the complex nature of supervision experiences and their impact on professional practice. This qualitative study explored the supervisory experiences of Australian-based Registered Music Therapists, according to the: 1) themes that characterize their experiences, 2) influences of the supervisor's professional background, 3) outcomes of supervision, and 4) roles of the employer, the professional music therapy association, and the university in supervision standards and practice. Seven professionals were interviewed for this study. Five stages of narrative analysis were used to create their supervision stories: a life course graph, narrative psychological analysis, component story framework and narrative analysis, analysis of narratives, and final integration of the seven narrative summaries. Findings revealed that supervision practice is influenced by a supervisee's personal and professional needs. A range of supervision models or approaches is recommended, including the access of supervisors from different professional backgrounds to support each stage of learning and development. A quality supervisory experience facilitates shifts in awareness and insight, which results in improved or increased skills, confidence, and accountability of practice. Participants' concern about stakeholders included a limited understanding of the role of the supervisor, a lack of clarity about accountability of supervisory practice, and minimal guidelines, which monitor professional competencies. The benefits of supervision in music therapy depend on the quality of the supervision provided, and clarity about the roles of those involved. Research and guidelines are recommended to target these areas. © the American Music Therapy Association 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  19. Patterns of Contact with Hospital for Children with an Autism Spectrum Disorder: A Danish Register-Based Study

    Science.gov (United States)

    Atladottir, Hjordis Osk; Schendel, Diana E.; Lauritsen, Marlene B.; Henriksen, Tine Brink; Parner, Erik T.

    2012-01-01

    The aim of this study was to study patterns of contact with hospital for children with autism spectrum disorder (ASD) using Danish population based register data. We included all children born in Denmark from 1994 through 2002. We found that children diagnosed with ASD had an increased rate of contact with hospital, almost regardless of the cause…

  20. Low but Increasing Prevalence of Autism Spectrum Disorders in a French Area from Register-Based Data

    Science.gov (United States)

    van Bakel, Marit Maria; Delobel-Ayoub, Malika; Cans, Christine; Assouline, Brigitte; Jouk, Pierre-Simon; Raynaud, Jean-Philippe; Arnaud, Catherine

    2015-01-01

    Register-based prevalence rates of childhood autism (CA), Asperger's syndrome (AS) and other autism spectrum disorders (ASD) were calculated among children aged 7 years old of the 1997-2003 birth cohorts, living in four counties in France. The proportion of children presenting comorbidities was reported. 1123 children with ASD were recorded (M/F…

  1. Quantum uncertainty relation based on the mean deviation

    OpenAIRE

    Sharma, Gautam; Mukhopadhyay, Chiranjib; Sazim, Sk; Pati, Arun Kumar

    2018-01-01

    Traditional forms of quantum uncertainty relations are invariably based on the standard deviation. This can be understood in the historical context of simultaneous development of quantum theory and mathematical statistics. Here, we present alternative forms of uncertainty relations, in both state dependent and state independent forms, based on the mean deviation. We illustrate the robustness of this formulation in situations where the standard deviation based uncertainty relation is inapplica...

  2. Special features of health services and register based trials – experiences from a randomized trial of childbirth classes

    Directory of Open Access Journals (Sweden)

    Sevón Tiina

    2008-06-01

    Full Text Available Abstract Background Evaluating complex interventions in health services faces various difficulties, such as making practice changes and costs. Ways to increase research capacity and decrease costs include making research an integral part of health services and using routine data to judge outcomes. The purpose of this article is to report the feasibility of a pilot trial relying solely on routinely collected register data and being based on ordinary health services. Methods The example intervention was education to public health nurses (PHN (childbirth classes to reduce caesarean section rates via pre-delivery considerations of pregnant women. 20 maternity health centers (MHC were paired and of each 10 pairs, one MHC was randomly allocated to an intervention group and the other to a control; 8 pairs with successful intervention were used in the analyses (1601 mothers. The women visiting to the study maternity centers were identified from the Customer Register of Helsinki City. A list of the study women was made using the mother's personal identification number, visit date, the maternity center code, birth date and gestation length. The mode of delivery and health outcomes were retrieved from the Finnish Medical Birth Register (MBR. Process data of the intervention are based on observations, written feedback and questionnaires from PHNs, and project correspondence. Results It took almost two years to establish how to obtain permissions and to actually obtain it for the trial. Obtaining permissions for the customer and outcome data and register linkages was unproblematic and the cluster randomization provided comparable groups. The intervention did not succeed well. Had the main aim of the trial been to cause a change in PHNs behavior, we would have very likely intensified the intervention during the trial. Conclusion Our experiences encourage the use of trials that obtain their outcomes from registers. Changing the behavior of ordinary health

  3. A Corpus-Based Approach to the Register Awareness of Asian Learners of English

    Science.gov (United States)

    Kobayashi, Yuichiro; Abe, Mariko

    2016-01-01

    The purpose of the present study is to investigate the impact of learners' L1s and proficiency levels on their written production. This study also examined the influence of speech upon their writing. The following research questions were explored: (a) How do L1 and proficiency levels of learners affect their degrees of register awareness? (b)…

  4. Psychosocial correlates of police-registered youth crime. A Finnish population-based study.

    Science.gov (United States)

    Elonheimo, Henrik; Sourander, Andre; Niemelä, Solja; Nuutila, Ari-Matti; Helenius, Hans; Sillanmäki, Lauri; Ristkari, Terja; Parkkola, Kai

    2009-01-01

    This study is focused on psychosocial correlates of youth crime in a sample of 2330 Finnish boys born in 1981. Two kinds of data were combined: questionnaires completed by the boys at call-up in 1999 and crime registered in the Finnish National Police Register between 1998 and 2001. One-fifth of the boys were registered to offending during the 4-year period in late adolescence; 14% were registered for one or two offences, 4% for three to five offences, and 3% for more than five offences. Crime accumulated heavily in those with more than five offences, as they accounted for 68% of all crime. Independent correlates of crime were living in a small community, parents' low educational level and divorce, having a regular relationship, self-reported delinquency, daily smoking, and weekly drunkenness, whereas anxious-depressiveness was reversely associated with crime. Most psychosocial problems covaried linearly with offending frequency, being particularly manifested by multiple recidivists. However, recidivists had very rarely used mental health services. The results indicate that offending and various psychosocial problems accumulate in a small minority of boys not reached by mental health services.

  5. Toward efficient fiber-based quantum interface (Conference Presentation)

    Science.gov (United States)

    Soshenko, Vladimir; Vorobyov, Vadim V.; Bolshedvorsky, Stepan; Lebedev, Nikolay; Akimov, Alexey V.; Sorokin, Vadim; Smolyaninov, Andrey

    2016-04-01

    NV center in diamond is attracting a lot of attention in quantum information processing community [1]. Been spin system in clean and well-controlled environment of diamond it shows outstanding performance as quantum memory even at room temperature, spin control with single shot optical readout and possibility to build up quantum registers even on single NV center. Moreover, NV centers could be used as high-resolution sensitive elements of detectors of magnetic or electric field, temperature, tension, force or rotation. For all of these applications collection of the light emitted by NV center is crucial point. There were number of approaches suggested to address this issue, proposing use of surface plasmoms [2], manufacturing structures in diamond [3] etc. One of the key feature of any practically important interface is compatibility with the fiber technology. Several groups attacking this problem using various approaches. One of them is placing of nanodiamonds in the holes of photonic crystal fiber [4], another is utilization of AFM to pick and place nanodiamond on the tapered fiber[5]. We have developed a novel technique of placing a nanodiamond with single NV center on the tapered fiber by controlled transfer of a nanodiamond from one "donor" tapered fiber to the "target" clean tapered fiber. We verify our ability to transfer only single color centers by means of measurement of second order correlation function. With this technique, we were able to double collection efficiency of confocal microscope. The majority of the factors limiting the collection of photons via optical fiber are technical and may be removed allowing order of magnitude improved in collection. We also discuss number of extensions of this technique to all fiber excitation and integration with nanostructures. References: [1] Marcus W. Doherty, Neil B. Manson, Paul Delaney, Fedor Jelezko, Jörg Wrachtrup, Lloyd C.L. Hollenberg , " The nitrogen-vacancy colour centre in diamond," Physics Reports

  6. Towards minimal resources of measurement-based quantum computation

    International Nuclear Information System (INIS)

    Perdrix, Simon

    2007-01-01

    We improve the upper bound on the minimal resources required for measurement-only quantum computation (M A Nielsen 2003 Phys. Rev. A 308 96-100; D W Leung 2004 Int. J. Quantum Inform. 2 33; S Perdrix 2005 Int. J. Quantum Inform. 3 219-23). Minimizing the resources required for this model is a key issue for experimental realization of a quantum computer based on projective measurements. This new upper bound also allows one to reply in the negative to the open question presented by Perdrix (2004 Proc. Quantum Communication Measurement and Computing) about the existence of a trade-off between observable and ancillary qubits in measurement-only QC

  7. Experimental quantum ratchets based on solid state nanostructures

    International Nuclear Information System (INIS)

    Linke, H.

    1999-01-01

    Ratchets are spatially asymmetric devices in which particles can move on average in one direction in the absence of external net forces or gradients. This is made possible by the rectification of fluctuations, which also provide the energy for the process. Interest in the physics of ratchets was revived in recent years when it emerged that the ratchet principle may be a suitable physical model for 'molecular motors', which are central to many fundamental biological processes, such as intracellular transport or muscle contraction. Most ratchets studied so far have relied on classical effects, but recently 'quantum ratchets', involving quantum effects, have also been studied. In the present article it is pointed out that semiconductor or metal nanostructures are very suitable systems for the realisation of experimental quantum ratchets. Recent experimental studies of a quantum ratchet based on an asymmetric quantum dot are reviewed. Copyright (1999) CSIRO Australia

  8. Critical components for diamond-based quantum coherent devices

    International Nuclear Information System (INIS)

    Greentree, Andrew D; Olivero, Paolo; Draganski, Martin; Trajkov, Elizabeth; Rabeau, James R; Reichart, Patrick; Gibson, Brant C; Rubanov, Sergey; Huntington, Shane T; Jamieson, David N; Prawer, Steven

    2006-01-01

    The necessary elements for practical devices exploiting quantum coherence in diamond materials are summarized, and progress towards their realization documented. A brief review of future prospects for diamond-based devices is also provided

  9. Relativistic supersymmetric quantum mechanics based on Klein-Gordon equation

    International Nuclear Information System (INIS)

    Znojil, Miloslav

    2004-01-01

    Witten's the non-relativistic formalism of supersymmetric quantum mechanics was based on a factorization and partnership between Schroedinger equations. We show how it accommodates a transition to the partnership between relativistic Klein-Gordon equations

  10. Bases in Lie and quantum algebras

    International Nuclear Information System (INIS)

    Ballesteros, A; Celeghini, E; Olmo, M A del

    2008-01-01

    Applications of algebras in physics are related to the connection of measurable observables to relevant elements of the algebras, usually the generators. However, in the determination of the generators in Lie algebras there is place for some arbitrary conventions. The situation is much more involved in the context of quantum algebras, where inside the quantum universal enveloping algebra, we have not enough primitive elements that allow for a privileged set of generators and all basic sets are equivalent. In this paper we discuss how the Drinfeld double structure underlying every simple Lie bialgebra characterizes uniquely a particular basis without any freedom, completing the Cartan program on simple algebras. By means of a perturbative construction, a distinguished deformed basis (we call it the analytical basis) is obtained for every quantum group as the analytical prolongation of the above defined Lie basis of the corresponding Lie bialgebra. It turns out that the whole construction is unique, so to each quantum universal enveloping algebra is associated one and only one bialgebra. In this way the problem of the classification of quantum algebras is moved to the classification of bialgebras. In order to make this procedure more clear, we discuss in detail the simple cases of su(2) and su q (2).

  11. Electron-longitudinal-acoustic-phonon scattering in double-quantum-dot based quantum gates

    International Nuclear Information System (INIS)

    Zhao Peiji; Woolard, Dwight L.

    2008-01-01

    We propose a nanostructure design which can significantly suppress longitudinal-acoustic-phonon-electron scattering in double-quantum-dot based quantum gates for quantum computing. The calculated relaxation rates vs. bias voltage exhibit a double-peak feature with a minimum approaching 10 5 s -1 . In this matter, the energy conservation law prohibits scattering contributions from phonons with large momenta; furthermore, increasing the barrier height between the double quantum dots reduces coupling strength between the dots. Hence, the joint action of the energy conservation law and the decoupling greatly reduces the scattering rates. The degrading effects of temperatures can be reduced simply by increasing the height of the barrier between the dots

  12. Quantum logic gates based on ballistic transport in graphene

    Energy Technology Data Exchange (ETDEWEB)

    Dragoman, Daniela [Faculty of Physics, University of Bucharest, P.O. Box MG-11, 077125 Bucharest (Romania); Academy of Romanian Scientists, Splaiul Independentei 54, 050094 Bucharest (Romania); Dragoman, Mircea, E-mail: mircea.dragoman@imt.ro [National Institute for Research and Development in Microtechnology (IMT), P.O. Box 38-160, 023573 Bucharest (Romania)

    2016-03-07

    The paper presents various configurations for the implementation of graphene-based Hadamard, C-phase, controlled-NOT, and Toffoli gates working at room temperature. These logic gates, essential for any quantum computing algorithm, involve ballistic graphene devices for qubit generation and processing and can be fabricated using existing nanolithographical techniques. All quantum gate configurations are based on the very large mean-free-paths of carriers in graphene at room temperature.

  13. A quantum computer based on recombination processes in microelectronic devices

    International Nuclear Information System (INIS)

    Theodoropoulos, K; Ntalaperas, D; Petras, I; Konofaos, N

    2005-01-01

    In this paper a quantum computer based on the recombination processes happening in semiconductor devices is presented. A 'data element' and a 'computational element' are derived based on Schokley-Read-Hall statistics and they can later be used to manifest a simple and known quantum computing process. Such a paradigm is shown by the application of the proposed computer onto a well known physical system involving traps in semiconductor devices

  14. An open-access mobile compatible electronic patient register for rheumatic heart disease (‘eRegister’) based on the World Heart Federation’s framework for patient registers

    Science.gov (United States)

    van Dam, Joris; Tadmor, Brigitta; Spector, Jonathan; Musuku, John; Zühlke, Liesl J; Zühlke, Liesl J; Engel, Mark E; Mayosi, Bongani M; Nestle, Nick

    2015-01-01

    Summary Background Rheumatic heart disease (RHD) remains a major disease burden in low-resource settings globally. Patient registers have long been recognised to be an essential instrument in RHD control and elimination programmes, yet to date rely heavily on paper-based data collection and non-networked data-management systems, which limit their functionality. Objectives To assess the feasibility and potential benefits of producing an electronic RHD patient register. Methods We developed an eRegister based on the World Heart Federation’s framework for RHD patient registers using CommCare, an open-source, cloud-based software for health programmes that supports the development of customised data capture using mobile devices. Results The resulting eRegistry application allows for simultaneous data collection and entry by field workers using mobile devices, and by providers using computer terminals in clinics and hospitals. Data are extracted from CommCare and are securely uploaded into a cloud-based database that matches the criteria established by the WHF framework. The application can easily be tailored to local needs by modifying existing variables or adding new ones. Compared with traditional paper-based data-collection systems, the eRegister reduces the risk of data error, synchronises in real-time, improves clinical operations and supports management of field team operations. Conclusions The user-friendly eRegister is a low-cost, mobile, compatible platform for RHD treatment and prevention programmes based on materials sanctioned by the World Heart Federation. Readily adaptable to local needs, this paperless RHD patient register program presents many practical benefits. PMID:26444995

  15. Nutritional rickets in Norway: a nationwide register-based cohort study.

    Science.gov (United States)

    Meyer, Haakon E; Skram, Kristina; Berge, Ingvill Almås; Madar, Ahmed A; Bjørndalen, Hilde Johanne

    2017-05-29

    Poor vitamin D status has been reported to be highly prevalent in many non-western immigrant groups living in Norway and other western countries. However, data on rickets are scarce, and the aim of the current study was to identify new cases of nutritional rickets in Norway in the period 2008-2012 among children under the age of 5 years. Register-based cohort study. The Norwegian population from 2008 to 2012. Children with nutritional rickets under the age of 5 years. Nutritional rickets. Patients with ICD10 (International Statistical Classification of Diseases and Related Health Problems, 10th revision) diagnosis code E55.0 (active rickets) treated at all Norwegian hospitals were identified in the Norwegian Patient Registry. We were able to review 85% of the medical records for diagnosis confirmation. In addition, we identified patients with the diagnoses E55.9, E64.3 and E83.3 to identify individuals with rickets who had been given other diagnoses. Nutritional rickets was confirmed in 39 children aged 0-4 years with the diagnosis of E55.0. In addition, three patients with the diagnosis of unspecified vitamin D deficiency (E55.9) were classified as having nutritional rickets, giving a total of 42 patients. Mean age at diagnosis was 1.40 years (range 0.1-3.5 years), and 93% had a non-western immigrant background. The incidence rate of rickets was estimated to be 0.3 per 10 000 person-years in the total Norwegian child population under the age of 5 years and 3.1 per 10 000 person-years in those with an immigrant background from Asia or Africa. The number of children with nutritional rickets in Norway remained low in the period 2008-2012. Nearly all children had a non-western immigrant background. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Mortality following unemployment during an economic downturn: Swedish register-based cohort study.

    Science.gov (United States)

    Montgomery, Scott; Udumyan, Ruzan; Magnuson, Anders; Osika, Walter; Sundin, Per-Ola; Blane, David

    2013-01-01

    To investigate if unemployment during an economic downturn is associated with mortality, even among men with markers of better health (higher cognitive function scores and qualifications), and to assess whether the associations vary by age at unemployment. Longitudinal register-based cohort study. Study entry was in 1990 and 2001 when Sweden was entering periods of significant economic contraction. A representative sample of men from the general population (n=234 782) born between 1952 and 1956 who participated in military conscription examinations. Men in receipt of disability or sickness benefit at study entry were excluded. All-cause mortality. Unemployment compared with employment in 1991 (ages 34-38 years) produced adjusted HRs (with 95% CIs) for all-cause mortality (3651 deaths) during follow-up to 2001 and after stratification by education of 2.35 (1.99 to 2.76) for compulsory education, 2.25 (1.97 to 2.58) for up to 3 years postcompulsory education and 1.90 (1.40 to 2.57) for more than 3 years postcompulsory education. When unemployment was compared with employment in 2001 (ages 45-49 years) with follow-up to 2010, the pattern of mortality risk (4271 deaths) stratified by education was reversed, producing adjusted HRs of 2.81 (2.47 to 3.21) for compulsory education, 2.87 (2.58 to 3.19) for up to 3 years postcompulsory education and 3.44 (2.78 to 4.25) for more than 3 years postcompulsory education. Interaction testing confirmed effect modification by age/period (p=0.003). The degree of gradient reversal was slightly less pronounced after stratification by cognitive function but produced a similar pattern of results (p=0.004). Unemployment at older ages is associated with greater mortality risk than at younger ages, with the greatest relative increase in risk among men with markers of better health, suggesting the greater vulnerability of all older workers to unemployment-associated exposures.

  17. Quantum gambling based on Nash-equilibrium

    Science.gov (United States)

    Zhang, Pei; Zhou, Xiao-Qi; Wang, Yun-Long; Liu, Bi-Heng; Shadbolt, Pete; Zhang, Yong-Sheng; Gao, Hong; Li, Fu-Li; O'Brien, Jeremy L.

    2017-06-01

    The problem of establishing a fair bet between spatially separated gambler and casino can only be solved in the classical regime by relying on a trusted third party. By combining Nash-equilibrium theory with quantum game theory, we show that a secure, remote, two-party game can be played using a quantum gambling machine which has no classical counterpart. Specifically, by modifying the Nash-equilibrium point we can construct games with arbitrary amount of bias, including a game that is demonstrably fair to both parties. We also report a proof-of-principle experimental demonstration using linear optics.

  18. Quantum teleportation. New wave of applications of quantum mechanics based on quantum entanglement: non-trivial transfer of quantum information

    International Nuclear Information System (INIS)

    Andrej, L.; Bednar, M.; Cernansky, M.

    1999-01-01

    The phenomenon of quantum teleportation is discussed with emphasis on its physical aspects. A brief introduction into the Einstein-Podolsky-Rosen (EPR) paradox is followed by Bohm's reformulation of the EPR paradox for the case of a physical system of two spins in the singlet state. A description of Bell's entangled spin states of two-particle systems of standard fermions as well as polarized photons is also given. In view of the fact that quantum teleportation has been realized experimentally mainly on photons, the next part of the paper is devoted to problems of generation and detection of two-photon Bell's entangled states. A detailed description of the process of quantum teleportation exploiting quantum entangled states follows. A classical formulation of the EPR paradox is given in the Appendix. (Z.J.)

  19. Psychosocial outcomes in adult men born with hypospadias: A register-based study.

    Directory of Open Access Journals (Sweden)

    Anna Skarin Nordenvall

    Full Text Available In this nationwide matched cohort study, we have investigated whether being born with hypospadias affect subsequent psychosocial outcomes in adulthood. We analyzed prospectively collected data from national Swedish registers. Data on the diagnoses were collected from the National Patient Register and the Medical Birth Register. Data on psychosocial outcomes such as educational and income level, marital status and disability pension were collected from Statistics Sweden. The effects of covariates, such as age, county of birth, presence of other malformations and psychiatric illness, were taken into account. The associations between hypospadias and psychosocial outcomes were calculated using conditional logistic regression and expressed as odds ratios (OR and 95% confidence intervals (CI. We included 4378 men diagnosed with hypospadias, born between 1969 and 1993 in Sweden. Patients with hypospadias were matched with unaffected men by year of birth and birth county. We did not detect any differences in educational or income level. The probability of entering marriage (OR 1.02, 95% CI 0.90-1.14 did not differ, regardless of phenotype. We did, however, detect a 40% increased probability of receiving a disability pension, (OR 1.39, 95% CI 1.20-1.61. In conclusion, men born with hypospadias in Sweden do not differ from unaffected men with respect to the majority of psychosocial outcomes studied. They are, however, at increased risk of receiving a disability pension, which motivates further investigations.

  20. Scalable quantum computing based on stationary spin qubits in coupled quantum dots inside double-sided optical microcavities.

    Science.gov (United States)

    Wei, Hai-Rui; Deng, Fu-Guo

    2014-12-18

    Quantum logic gates are the key elements in quantum computing. Here we investigate the possibility of achieving a scalable and compact quantum computing based on stationary electron-spin qubits, by using the giant optical circular birefringence induced by quantum-dot spins in double-sided optical microcavities as a result of cavity quantum electrodynamics. We design the compact quantum circuits for implementing universal and deterministic quantum gates for electron-spin systems, including the two-qubit CNOT gate and the three-qubit Toffoli gate. They are compact and economic, and they do not require additional electron-spin qubits. Moreover, our devices have good scalability and are attractive as they both are based on solid-state quantum systems and the qubits are stationary. They are feasible with the current experimental technology, and both high fidelity and high efficiency can be achieved when the ratio of the side leakage to the cavity decay is low.

  1. Evaluating the use and limitations of the Danish National Patient Register in register-based research using an example of multiple sclerosis.

    Science.gov (United States)

    Mason, K; Thygesen, L C; Stenager, E; Brønnum-Hansen, H; Koch-Henriksen, N

    2012-03-01

    The Danish National Patient Register, Landspatientregistret (LPR), is a register of all hospital discharges and outpatient treatments in Denmark. It is increasingly used in research so it is important to understand to what extent this can be used as an accurate source of information. Virtually all patients in Denmark with multiple sclerosis (MS) are reported to the Combined MS Registry (DMSR), so this was used as the standard which the LPR was compared against. All residents of Denmark are assigned a unique Civil Register (CPR) number; this was used to compare data between registers. The LPR completeness was estimated by the proportion of cases from the DMSR that could be retrieved from the LPR. The LPR validity was estimated by the proportion of cases, listed in the LPR and DMSR, in whom the MS diagnosis could be confirmed as definite/probable/possible by the DMSR. We found that 86.9% of those who were DMSR listed with an approved MS diagnosis were also listed in the LPR with a MS diagnosis. The diagnosis was valid in 96.3% of patients listed in the LPR when compared against the DMSR. The low completeness reduces the usefulness of the LPR in epidemiological MS research, in particular incidence studies. The study also found that the completeness of the LPR could be increased to 92.8% by including LPR records from other departments in addition, but this reduced the validity of the LPR to 95.1%. However, these results cannot uncritically be applied to registration of other diseases in the LPR. © 2011 John Wiley & Sons A/S.

  2. Quantum circuit implementation of cyclic mutually unbiased bases

    Energy Technology Data Exchange (ETDEWEB)

    Seyfarth, Ulrich; Dittmann, Niklas; Alber, Gernot [Institut fuer Angewandte Physik, Technische Universitaet Darmstadt, 64289 Darmstadt (Germany)

    2013-07-01

    Complete sets of mutually unbiased bases (MUBs) play an important role in the areas of quantum state tomography and quantum cryptography. Sets which can be generated cyclically may eliminate certain side-channel attacks. To profit from the advantages of these MUBs we propose a method for deriving a quantum circuit that implements the generator of a set into an experimental setup. For some dimensions this circuit is minimal. The presented method is in principle applicable for a larger set of operations and generalizes recently published results.

  3. One Step Quantum Key Distribution Based on EPR Entanglement.

    Science.gov (United States)

    Li, Jian; Li, Na; Li, Lei-Lei; Wang, Tao

    2016-06-30

    A novel quantum key distribution protocol is presented, based on entanglement and dense coding and allowing asymptotically secure key distribution. Considering the storage time limit of quantum bits, a grouping quantum key distribution protocol is proposed, which overcomes the vulnerability of first protocol and improves the maneuverability. Moreover, a security analysis is given and a simple type of eavesdropper's attack would introduce at least an error rate of 46.875%. Compared with the "Ping-pong" protocol involving two steps, the proposed protocol does not need to store the qubit and only involves one step.

  4. Quantum computing based on semiconductor nanowires

    NARCIS (Netherlands)

    Frolov, S.M.; Plissard, S.R.; Nadj-Perge, S.; Kouwenhoven, L.P.; Bakkers, E.P.A.M.

    2013-01-01

    A quantum computer will have computational power beyond that of conventional computers, which can be exploited for solving important and complex problems, such as predicting the conformations of large biological molecules. Materials play a major role in this emerging technology, as they can enable

  5. Could one make a diamond-based quantum computer?

    International Nuclear Information System (INIS)

    Stoneham, A Marshall; Harker, A H; Morley, Gavin W

    2009-01-01

    We assess routes to a diamond-based quantum computer, where we specifically look towards scalable devices, with at least 10 linked quantum gates. Such a computer should satisfy the deVincenzo rules and might be used at convenient temperatures. The specific examples that we examine are based on the optical control of electron spins. For some such devices, nuclear spins give additional advantages. Since there have already been demonstrations of basic initialization and readout, our emphasis is on routes to two-qubit quantum gate operations and the linking of perhaps 10-20 such gates. We analyse the dopant properties necessary, especially centres containing N and P, and give results using simple scoping calculations for the key interactions determining gate performance. Our conclusions are cautiously optimistic: it may be possible to develop a useful quantum information processor that works above cryogenic temperatures.

  6. Solid-State Quantum Computer Based on Scanning Tunneling Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Berman, G. P.; Brown, G. W.; Hawley, M. E.; Tsifrinovich, V. I.

    2001-08-27

    We propose a solid-state nuclear-spin quantum computer based on application of scanning tunneling microscopy (STM) and well-developed silicon technology. It requires the measurement of tunneling-current modulation caused by the Larmor precession of a single electron spin. Our envisioned STM quantum computer would operate at the high magnetic field ({approx}10 T) and at low temperature {approx}1 K .

  7. Solid-State Quantum Computer Based on Scanning Tunneling Microscopy

    International Nuclear Information System (INIS)

    Berman, G. P.; Brown, G. W.; Hawley, M. E.; Tsifrinovich, V. I.

    2001-01-01

    We propose a solid-state nuclear-spin quantum computer based on application of scanning tunneling microscopy (STM) and well-developed silicon technology. It requires the measurement of tunneling-current modulation caused by the Larmor precession of a single electron spin. Our envisioned STM quantum computer would operate at the high magnetic field (∼10 T) and at low temperature ∼1 K

  8. Hospital-based prevalence of chronic kidney disease among the newly registered patients with diabetes

    Directory of Open Access Journals (Sweden)

    P A Khanam

    2016-01-01

    Full Text Available Chronic kidney disease (CKD is proved to be a major public health issue worldwide and an important contributor to the overall non-communicable disease burden. It increases risk of mortality, end-stage renal disease and accelerated cardiovascular disease (CVD. Diabetes is the biggest contributor to CKD and end stage renal disease (ESRD. In Bangladesh, very few data on CKD is available. This study aimed to estimate the prevalence of CKD among the newly registered diabetic patients at BIRDEM (Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders, a referral center for diabetes in Bangladesh. Methods: The study included all diabetic patients aged 18 - 80 years and were registered in the year 2012. Socio-demographic (age, sex, residence, income, literacy, clinical (obesity, blood pressure and biochemical (blood glucose, lipids, eGFR information were collected from the BIRDEM registry. CKD was defined according to the K/ DOQI guidelines. Results: A total of 1317 type 2 diabetic patients of age 18 to 80 years were studied. Of them, men and women were 54.7% and 45.3%, respectively. The overall prevalence of CKD (eGFR ≤60 (ml/min/m2 was 13.9%. The prevalence was significantly higher in women than men (21.3 v. 7.8%, p50y, higher sBP (≥140mmHg and taking oral hypoglycemic agent (OHA were significant. Conclusions: Thus, the study concludes that the prevalence of CKD among the newly registered diabetic patients is quite high in Bangladesh. The female diabetic patients with older age and with higher SBP bear the brunt of CKD. Considering high prevalence of CKD with severe lifelong complications it is of utmost importance for early detection and intervention at the primary health care (PHC level.

  9. Hysterectomy on benign indication in Denmark 1988-1998. A register based trend analysis

    DEFF Research Database (Denmark)

    Gimbel, H; Settnes, A; Tabor, A

    2001-01-01

    BACKGROUND: The aims of the study were to describe the trends in Danish hysterectomy rates from 1988 to 1998 for operations done on benign indication. METHODS: Data from all women (n=67,096) undergoing hysterectomy from 1988 to 1998 were obtained from the Danish National Patient Register. Data...... by 14%. During the study period the number of total abdominal hysterectomies has decreased by 38%, the number of subtotal abdominal hysterectomies has increased by 458%, the number of vaginal hysterectomies has increased by 107% and two new methods of surgical treatment for benign diseases of the uterus...

  10. A Synoptic of Software Implementation for Shift Registers Based on 16th Degree Primitive Polynomials

    Directory of Open Access Journals (Sweden)

    Mirella Amelia Mioc

    2016-08-01

    Full Text Available Almost all of the major applications in the specific Fields of Communication used a well-known device called Linear Feedback Shift Register. Usually LFSR functions in a Galois Field GF(2n, meaning that all the operations are done with arithmetic modulo n degree Irreducible  and especially  Primitive Polynomials. Storing data in Galois Fields allows effective and manageable manipulation, mainly in computer cryptographic applications. The analysis of functioning for Primitive Polynomials of 16th degree shows that almost all the obtained results are in the same time distribution.

  11. Relational coordination is associated with productivity in general practice: a survey and register based study

    DEFF Research Database (Denmark)

    Lundstrøm, Sanne Lykke; Edwards, Kasper; Reventlow, Susanne

    2014-01-01

    In this paper we investigate the association between relational coordination among the practice team in general practice and number of consultations performed in a general practice per staff, i.e. a proxy of productivity. We measured relational coordination using the Relational Coordination Survey...... and combined the results with register data. We found that relational coordination was statistically significant associated with number of consultation per staff per year. We later divided consultations in to three types: Face-to-face, Email and phone consultations. We found a statistically significant...... associating between relational coordination and with number of face-to-face consultation per staff per year....

  12. Analysis of risk factors for schizophrenia with two different case definitions: a nationwide register-based external validation study.

    Science.gov (United States)

    Sørensen, Holger J; Larsen, Janne T; Mors, Ole; Nordentoft, Merete; Mortensen, Preben B; Petersen, Liselotte

    2015-03-01

    Different case definitions of schizophrenia have been used in register based research. However, no previous study has externally validated two different case definitions of schizophrenia against a wide range of risk factors for schizophrenia. We investigated hazard ratios (HRs) for a wide range of risk factors for ICD-10 DCR schizophrenia using a nationwide Danish sample of 2,772,144 residents born in 1955-1997. We compared one contact only (OCO) (the case definition of schizophrenia used in Danish register based studies) with two or more contacts (TMC) (a case definition of at least 2 inpatient contacts with schizophrenia). During the follow-up, the OCO definition included 15,074 and the TMC 7562 cases; i.e. half as many. The TMC case definition appeared to select for a worse illness course. A wide range of risk factors were uniformly associated with both case definitions and only slightly higher risk estimates were found for the TMC definition. Choosing at least 2 inpatient contacts with schizophrenia (TMC) instead of the currently used case definition would result in almost similar risk estimates for many well-established risk factors. However, this would also introduce selection and include considerably fewer cases and reduce power of e.g. genetic studies based on register-diagnosed cases only. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. IT Risk register

    OpenAIRE

    Kohout, Karel

    2011-01-01

    The theoretical part of the thesis analyzes several selected methodologies and best-practices related to information technology risks management, with focus on documents and guidance developed by ISACA. It builds a set of ideas and basic requirements for effective model of an IT risk register. Strong emphasis is placed on mapping CobiT 4.1 based Risk IT to COBIT 5. The practical part describes implementation of an exploratory web-based IT risk register in Python programming language utilizing...

  14. Autonomous quantum Maxwell's demon based on two exchange-coupled quantum dots

    Science.gov (United States)

    Ptaszyński, Krzysztof

    2018-01-01

    I study an autonomous quantum Maxwell's demon based on two exchange-coupled quantum dots attached to the spin-polarized leads. The principle of operation of the demon is based on the coherent oscillations between the spin states of the system which act as a quantum iSWAP gate. Due to the operation of the iSWAP gate, one of the dots acts as a feedback controller which blocks the transport with the bias in the other dot, thus inducing the electron pumping against the bias; this leads to the locally negative entropy production. Operation of the demon is associated with the information transfer between the dots, which is studied quantitatively by mapping the analyzed setup onto the thermodynamically equivalent auxiliary system. The calculated entropy production in a single subsystem and information flow between the subsystems are shown to obey a local form of the second law of thermodynamics, similar to the one previously derived for classical bipartite systems.

  15. FAST TRACK COMMUNICATION: Graphene based quantum dots

    Science.gov (United States)

    Zhang, H. G.; Hu, H.; Pan, Y.; Mao, J. H.; Gao, M.; Guo, H. M.; Du, S. X.; Greber, T.; Gao, H.-J.

    2010-08-01

    Laterally localized electronic states are identified on a single layer of graphene on ruthenium by low temperature scanning tunneling spectroscopy (STS). The individual states are separated by 3 nm and comprise regions of about 90 carbon atoms. This constitutes a highly regular quantum dot-array with molecular precision. It is evidenced by quantum well resonances (QWRs) with energies that relate to the corrugation of the graphene layer. The dI/dV conductance spectra are modeled by a layer height dependent potential-well with a delta-function potential that describes the barrier for electron penetration into graphene. The resulting QWRs are strongest and lowest in energy on the isolated 'hill' regions with a diameter of 2 nm, where the graphene is decoupled from the surface.

  16. Quantum Secure Direct Communication Based on Authentication

    International Nuclear Information System (INIS)

    Min-Jie, Wang; Wei, Pan

    2008-01-01

    We propose two schemes of quantum secure direct communication (QSDC) combined ideas of user authentication [Phys. Rev. A 73 (2006) 042305] and direct communication with dense coding [Phys. Rev. A. 68 (2003) 042317]. In these protocols, the privacy of authentication keys and the properties of the EPR pairs not only ensure the realization of identity authentication but also further improve the security of communication, and no secret messages are leaked even if the messages were broken. (general)

  17. Initialization Errors in Quantum Data Base Recall

    OpenAIRE

    Natu, Kalyani

    2016-01-01

    This paper analyzes the relationship between initialization error and recall of a specific memory in the Grover algorithm for quantum database search. It is shown that the correct memory is obtained with high probability even when the initial state is far removed from the correct one. The analysis is done by relating the variance of error in the initial state to the recovery of the correct memory and the surprising result is obtained that the relationship between the two is essentially linear.

  18. Combining variational and model-based techniques to register PET and MR images in hand osteoarthritis

    International Nuclear Information System (INIS)

    Magee, Derek; Tanner, Steven F; Jeavons, Alan P; Waller, Michael; Tan, Ai Lyn; McGonagle, Dennis

    2010-01-01

    Co-registration of clinical images acquired using different imaging modalities and equipment is finding increasing use in patient studies. Here we present a method for registering high-resolution positron emission tomography (PET) data of the hand acquired using high-density avalanche chambers with magnetic resonance (MR) images of the finger obtained using a 'microscopy coil'. This allows the identification of the anatomical location of the PET radiotracer and thereby locates areas of active bone metabolism/'turnover'. Image fusion involving data acquired from the hand is demanding because rigid-body transformations cannot be employed to accurately register the images. The non-rigid registration technique that has been implemented in this study uses a variational approach to maximize the mutual information between images acquired using these different imaging modalities. A piecewise model of the fingers is employed to ensure that the methodology is robust and that it generates an accurate registration. Evaluation of the accuracy of the technique is tested using both synthetic data and PET and MR images acquired from patients with osteoarthritis. The method outperforms some established non-rigid registration techniques and results in a mean registration error that is less than approximately 1.5 mm in the vicinity of the finger joints.

  19. Epilepsy in Sweden: health care costs and loss of productivity--a register-based approach.

    Science.gov (United States)

    Bolin, Kristian; Lundgren, Anders; Berggren, Fredrik; Källén, Kristina

    2012-12-01

    The objective was to estimate health care costs and productivity losses due to epilepsy in Sweden and to compare these estimates to previously published estimates. Register data on health care utilisation, pharmaceutical sales, permanent disability and mortality were used to calculate health care costs and costs that accrue due to productivity losses. By linkage of register information, we were able to distinguish pharmaceuticals prescribed against epilepsy from prescriptions that were prompted by other indications. The estimated total cost of epilepsy in Sweden in 2009 was 441 million, which corresponds to an annual per-patient cost of 8,275. Health care accounted for about 16% of the estimated total cost, and drug costs accounted for about 7% of the total cost. The estimated health care cost corresponded to about 0.2% of the total health care cost in Sweden in 2009. Indirect costs were estimated at 370 million, 84% of which was due to sickness absenteeism. Costs resulting from epilepsy-attributable premature deaths or permanent disability to work accounted for about 1% of the total indirect cost in Sweden in 2009. The per-patient cost of epilepsy is substantial. Thus, even though the prevalence of the illness is relatively small, the aggregated cost that epilepsy incurs on society is significant.

  20. Diamond-based Fabry-Perot microcavities for quantum networks

    NARCIS (Netherlands)

    Bogdanovic, S.

    2017-01-01

    A quantumnetwork would allow the distribution of a quantum state over many spatially separated quantum nodes which individually possess the ability to generate, process and store quantum information. Connecting these nodes through quantum communication channels would enable sending quantum

  1. Quantum game theory based on the Schmidt decomposition

    International Nuclear Information System (INIS)

    Ichikawa, Tsubasa; Tsutsui, Izumi; Cheon, Taksu

    2008-01-01

    We present a novel formulation of quantum game theory based on the Schmidt decomposition, which has the merit that the entanglement of quantum strategies is manifestly quantified. We apply this formulation to 2-player, 2-strategy symmetric games and obtain a complete set of quantum Nash equilibria. Apart from those available with the maximal entanglement, these quantum Nash equilibria are extensions of the Nash equilibria in classical game theory. The phase structure of the equilibria is determined for all values of entanglement, and thereby the possibility of resolving the dilemmas by entanglement in the game of Chicken, the Battle of the Sexes, the Prisoners' Dilemma, and the Stag Hunt, is examined. We find that entanglement transforms these dilemmas with each other but cannot resolve them, except in the Stag Hunt game where the dilemma can be alleviated to a certain degree

  2. Self-guaranteed measurement-based quantum computation

    Science.gov (United States)

    Hayashi, Masahito; Hajdušek, Michal

    2018-05-01

    In order to guarantee the output of a quantum computation, we usually assume that the component devices are trusted. However, when the total computation process is large, it is not easy to guarantee the whole system when we have scaling effects, unexpected noise, or unaccounted for correlations between several subsystems. If we do not trust the measurement basis or the prepared entangled state, we do need to be worried about such uncertainties. To this end, we propose a self-guaranteed protocol for verification of quantum computation under the scheme of measurement-based quantum computation where no prior-trusted devices (measurement basis or entangled state) are needed. The approach we present enables the implementation of verifiable quantum computation using the measurement-based model in the context of a particular instance of delegated quantum computation where the server prepares the initial computational resource and sends it to the client, who drives the computation by single-qubit measurements. Applying self-testing procedures, we are able to verify the initial resource as well as the operation of the quantum devices and hence the computation itself. The overhead of our protocol scales with the size of the initial resource state to the power of 4 times the natural logarithm of the initial state's size.

  3. Quantum-classical interface based on single flux quantum digital logic

    Science.gov (United States)

    McDermott, R.; Vavilov, M. G.; Plourde, B. L. T.; Wilhelm, F. K.; Liebermann, P. J.; Mukhanov, O. A.; Ohki, T. A.

    2018-04-01

    We describe an approach to the integrated control and measurement of a large-scale superconducting multiqubit array comprising up to 108 physical qubits using a proximal coprocessor based on the Single Flux Quantum (SFQ) digital logic family. Coherent control is realized by irradiating the qubits directly with classical bitstreams derived from optimal control theory. Qubit measurement is performed by a Josephson photon counter, which provides access to the classical result of projective quantum measurement at the millikelvin stage. We analyze the power budget and physical footprint of the SFQ coprocessor and discuss challenges and opportunities associated with this approach.

  4. Non-binary unitary error bases and quantum codes

    Energy Technology Data Exchange (ETDEWEB)

    Knill, E.

    1996-06-01

    Error operator bases for systems of any dimension are defined and natural generalizations of the bit-flip/ sign-change error basis for qubits are given. These bases allow generalizing the construction of quantum codes based on eigenspaces of Abelian groups. As a consequence, quantum codes can be constructed form linear codes over {ital Z}{sub {ital n}} for any {ital n}. The generalization of the punctured code construction leads to many codes which permit transversal (i.e. fault tolerant) implementations of certain operations compatible with the error basis.

  5. Dementia and traffic accidents: a Danish register-based cohort study

    DEFF Research Database (Denmark)

    Petersen, Jindong Ding; Siersma, Volkert Dirk; Nielsen, CT

    2016-01-01

    BACKGROUND: As a consequence of a rapid growth of an ageing population, more people with dementia are expected on the roads. Little is known about whether these people are at increased risk of road traffic-related accidents. OBJECTIVE: Our study aims to investigate the risk of road traffic...... Central Research Register, and/or (2) at least one dementia diagnosis-related drug prescription registration in the Danish National Prescription Registry. Police-, hospital-, and emergency room-reported road traffic-related accidents occurred within the study follow-up are defined as the study outcome...... selection bias due to nonparticipation and loss to follow-up. Furthermore, this ensures that the study results are reliable and generalizable. However, underreporting of traffic-related accidents may occur, which will limit estimation of absolute risks....

  6. Danish register-based study on the association between specific cardiovascular drugs and fragility fractures

    DEFF Research Database (Denmark)

    Torstensson, Maia; Hansen, Annette Højmann; Leth-Møller, Katja

    2015-01-01

    OBJECTIVE: To determine whether drugs used in treatment of cardiovascular diseases (CVD-drugs), including hypertension, increase the risk of fragility fractures in individuals above the age of 65 years. DESIGN: Retrospective nationwide cohort study. SETTING: Danish nationwide national registers...... and statins) was determined by prescription claims from pharmacies. The association between use of specific CVD-drugs and fragility fractures was assessed using multivariable Poisson regression models, and adjusted incidence rate ratios (IRRs) were calculated. RESULTS: Overall, 1 586 554 persons were included......, of these 16.1% experienced a fall-related fracture. The multivariable Poisson regression analysis showed positive associations between fracture and treatment with furosemide, thiazide and digoxin. IRRs during the first 14 days of treatment were for furosemide IRR 1.74 (95% CI 1.61 to 1.89) and for thiazides...

  7. Health Care Use by Patients with Somatoform Disorders A Register-Based Follow-Up Study*

    DEFF Research Database (Denmark)

    Andersen, Nadia Lyhne Trærup; Eplov, Lene Falgaard; Andersen, Jon Trærup

    2012-01-01

    the background population. Data from the Danish National Registers were used to assess health care use in both primary and secondary care. RESULTS: Somatoform patients incurred 2.11 (2.09-2.12) times the primary care visits of controls. They had 3.12 (3.08-3.16) times as many somatic bed-days than controls and 3.......94 (3.91-3.97) as many psychiatric bed-days. Primary care use remained stable 3 years after diagnosis (p = 0.14) and the award of disability pension (p = 0.82). However, the number of somatic admissions decreased from 5.64 to 2.76 (p = 0.0004) 3 years after diagnosis. Somatization had an independent...... of somatic health care was independent of psychiatric comorbidity. Primary care use and disability pension award were not influenced by proper diagnosing of somatoform disorders whereas number of somatic admissions were halved....

  8. An observational nationwide register based cohort study on lamotrigine versus lithium in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Hellmund, Gunnar; Andersen, Per Kragh

    2012-01-01

    It is not clear whether the effectiveness of lamotrigine versus lithium differs for patients with bipolar disorder treated in clinical practice. We compared rates of switch to, or add on of, another psychotropic, and rates of psychiatric hospitalization for patients treated with lamotrigine...... or lithium in clinical practice. Using linkage of nationwide Danish registers we identified 730 patients who received lamotrigine and 3518 patients received lithium subsequent to a diagnosis of bipolar disorder in psychiatric hospital settings during a period from 1995 to 2006. The overall rate of switch...... to or add on of another psychotropic (the opposite drug of interest (lithium or lamotrigine), antidepressants, antipsychotics or other anticonvulsants than lamotrigine) was increased for lamotrigine compared with lithium (HR = 2.60, 95% CI: 2.23-3.04), regardless of whether the index episode was depressive...

  9. An observational nationwide register based cohort study on lamotrigine versus lithium in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Hellmund, Gunnar; Andersen, Per Kragh

    2011-01-01

    It is not clear whether the effectiveness of lamotrigine versus lithium differs for patients with bipolar disorder treated in clinical practice. We compared rates of switch to, or add on of, another psychotropic, and rates of psychiatric hospitalization for patients treated with lamotrigine...... or lithium in clinical practice. Using linkage of nationwide Danish registers we identified 730 patients who received lamotrigine and 3518 patients received lithium subsequent to a diagnosis of bipolar disorder in psychiatric hospital settings during a period from 1995 to 2006. The overall rate of switch...... to or add on of another psychotropic (the opposite drug of interest (lithium or lamotrigine), antidepressants, antipsychotics or other anticonvulsants than lamotrigine) was increased for lamotrigine compared with lithium (HR = 2.60, 95% CI: 2.23-3.04), regardless of whether the index episode was depressive...

  10. Increased Risk of Developing Affective Disorder in Patients with Hypothyroidism: A Register-Based Study

    DEFF Research Database (Denmark)

    Thomsen, Anders F.; Kvist, Tine Kajsa; Andersen, Per Kragh

    2005-01-01

    BACKGROUND: Links between thyroid function and depression have been noted in many contexts. We assessed whether hospitalization with hypothyroidism was a risk factor for developing affective disorder. METHODS: We conducted a prospective cohort study using historical data from Danish registers....... The observational period was 1977-1999. Three study cohorts were identified: all patients with a first hospital admittance with the resulting index discharge diagnoses hypothyroidism, osteoarthritis, or nontoxic goiter. A later hospitalization with a resulting discharge diagnosis of affective disorder was used...... as event of interest, and rates of readmission were estimated and compared using competing risk models in survival analyses. FINDINGS: We identified 165,307 patients discharged with an index diagnosis. In the observational period, 1041 events occurred. An index diagnosis of hypothyroidism was associated...

  11. Resource allocation of in vitro fertilization: a nationwide register-based cohort study

    Directory of Open Access Journals (Sweden)

    Sevón Tiina

    2007-12-01

    Full Text Available Abstract Background Infertility is common and in vitro fertilization (IVF is a widely used treatment. In IVF the need increases and the effectiveness and appropriateness decrease by age. The purpose of this study was to describe allocation of resources for IVF by women's age, socioeconomic position, area of residence and treatment sector (public vs. private and to discuss how fairly the IVF resources are allocated in Finland. Methods Women who received IVF between 1996 and 1998 (N = 9175 were identified from the reimbursement records of the Social Insurance Institution (SII. Information on IVF women's background characteristics came from the Central Population Register and the SII, on treatment costs from IVF clinics and the SII, and on births from the Medical Birth Register. The main outcome measures were success of IVF by number of cycles and treated women, expenditures per IVF cycles, per women, per live-birth, and per treatment sector, and private and public expenditures. Expenditures were estimated from health care visits and costs. Results During a mean period of 1.5 years, older women (women aged 40 or older received 1.4 times more IVF treatment cycles than younger women (women aged below 30. The success rate decreased by age: from 22 live births per 100 cycles among younger women to 6 per 100 among older women. The mean cost of a live birth increased by age: compared to younger women, costs per born live birth of older women were 3-fold. Calculated by population, public expenditure was allocated most to young women and women from the highest socioeconomic position. Regional differences were not remarkable. Conclusion Children of older infertile women involve more expense due to the lower success rates of IVF. Socioeconomic differences suggest unfair resource allocation in Finland.

  12. Resource allocation of in vitro fertilization: a nationwide register-based cohort study

    Science.gov (United States)

    Klemetti, Reija; Gissler, Mika; Sevón, Tiina; Hemminki, Elina

    2007-01-01

    Background Infertility is common and in vitro fertilization (IVF) is a widely used treatment. In IVF the need increases and the effectiveness and appropriateness decrease by age. The purpose of this study was to describe allocation of resources for IVF by women's age, socioeconomic position, area of residence and treatment sector (public vs. private) and to discuss how fairly the IVF resources are allocated in Finland. Methods Women who received IVF between 1996 and 1998 (N = 9175) were identified from the reimbursement records of the Social Insurance Institution (SII). Information on IVF women's background characteristics came from the Central Population Register and the SII, on treatment costs from IVF clinics and the SII, and on births from the Medical Birth Register. The main outcome measures were success of IVF by number of cycles and treated women, expenditures per IVF cycles, per women, per live-birth, and per treatment sector, and private and public expenditures. Expenditures were estimated from health care visits and costs. Results During a mean period of 1.5 years, older women (women aged 40 or older) received 1.4 times more IVF treatment cycles than younger women (women aged below 30). The success rate decreased by age: from 22 live births per 100 cycles among younger women to 6 per 100 among older women. The mean cost of a live birth increased by age: compared to younger women, costs per born live birth of older women were 3-fold. Calculated by population, public expenditure was allocated most to young women and women from the highest socioeconomic position. Regional differences were not remarkable. Conclusion Children of older infertile women involve more expense due to the lower success rates of IVF. Socioeconomic differences suggest unfair resource allocation in Finland. PMID:18154645

  13. Resource allocation of in vitro fertilization: a nationwide register-based cohort study.

    Science.gov (United States)

    Klemetti, Reija; Gissler, Mika; Sevón, Tiina; Hemminki, Elina

    2007-12-21

    Infertility is common and in vitro fertilization (IVF) is a widely used treatment. In IVF the need increases and the effectiveness and appropriateness decrease by age. The purpose of this study was to describe allocation of resources for IVF by women's age, socioeconomic position, area of residence and treatment sector (public vs. private) and to discuss how fairly the IVF resources are allocated in Finland. Women who received IVF between 1996 and 1998 (N = 9175) were identified from the reimbursement records of the Social Insurance Institution (SII). Information on IVF women's background characteristics came from the Central Population Register and the SII, on treatment costs from IVF clinics and the SII, and on births from the Medical Birth Register. The main outcome measures were success of IVF by number of cycles and treated women, expenditures per IVF cycles, per women, per live-birth, and per treatment sector, and private and public expenditures. Expenditures were estimated from health care visits and costs. During a mean period of 1.5 years, older women (women aged 40 or older) received 1.4 times more IVF treatment cycles than younger women (women aged below 30). The success rate decreased by age: from 22 live births per 100 cycles among younger women to 6 per 100 among older women. The mean cost of a live birth increased by age: compared to younger women, costs per born live birth of older women were 3-fold. Calculated by population, public expenditure was allocated most to young women and women from the highest socioeconomic position. Regional differences were not remarkable. Children of older infertile women involve more expense due to the lower success rates of IVF. Socioeconomic differences suggest unfair resource allocation in Finland.

  14. Quantum Color Image Encryption Algorithm Based on A Hyper-Chaotic System and Quantum Fourier Transform

    Science.gov (United States)

    Tan, Ru-Chao; Lei, Tong; Zhao, Qing-Min; Gong, Li-Hua; Zhou, Zhi-Hong

    2016-12-01

    To improve the slow processing speed of the classical image encryption algorithms and enhance the security of the private color images, a new quantum color image encryption algorithm based on a hyper-chaotic system is proposed, in which the sequences generated by the Chen's hyper-chaotic system are scrambled and diffused with three components of the original color image. Sequentially, the quantum Fourier transform is exploited to fulfill the encryption. Numerical simulations show that the presented quantum color image encryption algorithm possesses large key space to resist illegal attacks, sensitive dependence on initial keys, uniform distribution of gray values for the encrypted image and weak correlation between two adjacent pixels in the cipher-image.

  15. Secure multi-party quantum summation based on quantum Fourier transform

    Science.gov (United States)

    Yang, Hui-Yi; Ye, Tian-Yu

    2018-06-01

    In this paper, we propose a novel secure multi-party quantum summation protocol based on quantum Fourier transform, where the traveling particles are transmitted in a tree-type mode. The party who prepares the initial quantum states is assumed to be semi-honest, which means that she may misbehave on her own but will not conspire with anyone. The proposed protocol can resist both the outside attacks and the participant attacks. Especially, one party cannot obtain other parties' private integer strings; and it is secure for the colluding attack performed by at most n - 2 parties, where n is the number of parties. In addition, the proposed protocol calculates the addition of modulo d and implements the calculation of addition in a secret-by-secret way rather than a bit-by-bit way.

  16. Quantum probability ranking principle for ligand-based virtual screening

    Science.gov (United States)

    Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal

    2017-04-01

    Chemical libraries contain thousands of compounds that need screening, which increases the need for computational methods that can rank or prioritize compounds. The tools of virtual screening are widely exploited to enhance the cost effectiveness of lead drug discovery programs by ranking chemical compounds databases in decreasing probability of biological activity based upon probability ranking principle (PRP). In this paper, we developed a novel ranking approach for molecular compounds inspired by quantum mechanics, called quantum probability ranking principle (QPRP). The QPRP ranking criteria would make an attempt to draw an analogy between the physical experiment and molecular structure ranking process for 2D fingerprints in ligand based virtual screening (LBVS). The development of QPRP criteria in LBVS has employed the concepts of quantum at three different levels, firstly at representation level, this model makes an effort to develop a new framework of molecular representation by connecting the molecular compounds with mathematical quantum space. Secondly, estimate the similarity between chemical libraries and references based on quantum-based similarity searching method. Finally, rank the molecules using QPRP approach. Simulated virtual screening experiments with MDL drug data report (MDDR) data sets showed that QPRP outperformed the classical ranking principle (PRP) for molecular chemical compounds.

  17. Quantum probability ranking principle for ligand-based virtual screening.

    Science.gov (United States)

    Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal

    2017-04-01

    Chemical libraries contain thousands of compounds that need screening, which increases the need for computational methods that can rank or prioritize compounds. The tools of virtual screening are widely exploited to enhance the cost effectiveness of lead drug discovery programs by ranking chemical compounds databases in decreasing probability of biological activity based upon probability ranking principle (PRP). In this paper, we developed a novel ranking approach for molecular compounds inspired by quantum mechanics, called quantum probability ranking principle (QPRP). The QPRP ranking criteria would make an attempt to draw an analogy between the physical experiment and molecular structure ranking process for 2D fingerprints in ligand based virtual screening (LBVS). The development of QPRP criteria in LBVS has employed the concepts of quantum at three different levels, firstly at representation level, this model makes an effort to develop a new framework of molecular representation by connecting the molecular compounds with mathematical quantum space. Secondly, estimate the similarity between chemical libraries and references based on quantum-based similarity searching method. Finally, rank the molecules using QPRP approach. Simulated virtual screening experiments with MDL drug data report (MDDR) data sets showed that QPRP outperformed the classical ranking principle (PRP) for molecular chemical compounds.

  18. Pseudo random number generator based on quantum chaotic map

    Science.gov (United States)

    Akhshani, A.; Akhavan, A.; Mobaraki, A.; Lim, S.-C.; Hassan, Z.

    2014-01-01

    For many years dissipative quantum maps were widely used as informative models of quantum chaos. In this paper, a new scheme for generating good pseudo-random numbers (PRNG), based on quantum logistic map is proposed. Note that the PRNG merely relies on the equations used in the quantum chaotic map. The algorithm is not complex, which does not impose high requirement on computer hardware and thus computation speed is fast. In order to face the challenge of using the proposed PRNG in quantum cryptography and other practical applications, the proposed PRNG is subjected to statistical tests using well-known test suites such as NIST, DIEHARD, ENT and TestU01. The results of the statistical tests were promising, as the proposed PRNG successfully passed all these tests. Moreover, the degree of non-periodicity of the chaotic sequences of the quantum map is investigated through the Scale index technique. The obtained result shows that, the sequence is more non-periodic. From these results it can be concluded that, the new scheme can generate a high percentage of usable pseudo-random numbers for simulation and other applications in scientific computing.

  19. Quantum information generation, storage and transmission based on nuclear spins

    Science.gov (United States)

    Zaharov, V. V.; Makarov, V. I.

    2018-05-01

    A new approach to quantum information generation, storage and transmission is proposed. It is shown that quantum information generation and storage using an ensemble of N electron spins encounter unresolvable implementation problems (at least at the present time). As an alternative implementation we discuss two promising radical systems, one with N equivalent nuclear spins and another with N nonequivalent nuclear spins. Detailed analysis shows that only the radical system containing N nonequivalent nuclei is perfectly matched for quantum information generation, storage and transmission. We develop a procedure based on pulsed electron paramagnetic resonance (EPR) and we apply it to the radical system with the set of nonequivalent nuclei. The resulting EPR spectrum contains 2N transition lines, where N is the number of the atoms with the nuclear spin 1/2, and each of these lines may be encoded with a determined qudit sequence. For encoding the EPR lines we propose to submit the radical system to two magnetic pulses in the direction perpendicular to the z axis of the reference frame. As a result, the radical system impulse response may be measured, stored and transmitted through the communications channel. Confirming our development, the ab initio analysis of the system with three anion radicals was done showing matching between the simulations and the theoretical predictions. The developed method may be easily adapted for quantum information generation, storage, processing and transmission in quantum computing and quantum communications applications.

  20. Quantum spacetime operationally based on propagators for extended test particles

    International Nuclear Information System (INIS)

    Prugovecki, E.

    1981-01-01

    By taking into account the quantum aspects intrinsic to any operational definition of spatio-temporal relationships, a stochastic concept of spacetime emerges. In relation to its classical counterpart is realized as a stochastic mean around which quantum fluctuations become negligible only in the limit of macroscopic spacetime intervals. The test-particle propagators used in the proposed quantum concept of spacetime are derived by solving in a consistent manner the localizability problem for relativistic particles. This is achieved in the framework of the stochastic phase space formulation of quantum mechanics, which in the nonrelativistic context is shown to result from systems of imprimitivity related to phase space conserved probability currents derivable from bona fide convariant probability densities in stochastic phase spaces of one particle systems, which can be interpreted as due to measurements performed with extended rather than pointlike test particles. The associated particle propagators can be therefore consistently related to coordinate probability densities measurable by the exchange of photons in between test particles from a chosen standard. Quantum spacetime is defined as the family of propagators corresponding to all conceivable coherent flows of test particles. This family of free-fall propagators has to satisfy certain self-consistency conditions as well as consistent laws of motion which inplicitly determine the stochastic geometro-dynamics of quantum space-time. Field theory on quantum spacetime retains many of the formal features of conventional quantum field theory. On a fundamental epistemological level stochastic geometries emerge as essential prerequisites in the construction of spacetime models that would be operationally based and yet consistent with the relativity principle as well as with the uncertinty principle

  1. Epidemiology of cardiovascular malformations among newborns in Monchegorsk (north-west Russia: a register-based study

    Directory of Open Access Journals (Sweden)

    Vitaly A. Postoev

    2014-08-01

    Full Text Available Background. Cardiovascular malformations (CVM are one of the most prevalent groups of birth defects. Knowledge about the prevalence, distribution and survival in Russia has been limited. The aim of our study was to assess the perinatal prevalence, structure and risk factors for CVM among newborns in Monchegorsk (Murmansk Oblast, Russia and the mortality among the affected newborns in the period 1973-2008. Design and methods. A register-based study on data from the Kola and Murmansk County Birth Registers. The study included 28,511 births. Results. The registered perinatal prevalence was 3.0 per 1000 newborns, with septal defects as the most prevalent. CVM was twenty times more prevalent among stillborn than live born, and one-third of the live born with a CVM died during the first week of life. The perinatal mortality rate with CVM was 442 per 1000 newborns. This indicator decreased over time. The mothers of newborns with a CVM were ten times more likely to have stillbirth in their anamnesis. The adjusted odds ratio between maternal smoking during pregnancy and CVM was 4.09 [95% confidence interval: 1.75-9.53]. Conclusions. The diagnosed perinatal prevalence was relatively low. A previous stillbirth by the mother was highly associated with being born with a CVM. An adjusted elevated risk was also observed among smoking mothers. Perinatal survival increased over time, but varied to a large extent between the different types of CVM.

  2. Molecular Electronic Shift Registers

    Science.gov (United States)

    Beratan, David N.; Onuchic, Jose N.

    1990-01-01

    Molecular-scale shift registers eventually constructed as parts of high-density integrated memory circuits. In principle, variety of organic molecules makes possible large number of different configurations and modes of operation for such shift-register devices. Several classes of devices and implementations in some specific types of molecules proposed. All based on transfer of electrons or holes along chains of repeating molecular units.

  3. Milestones Toward Majorana-Based Quantum Computing

    Directory of Open Access Journals (Sweden)

    David Aasen

    2016-08-01

    Full Text Available We introduce a scheme for preparation, manipulation, and read out of Majorana zero modes in semiconducting wires with mesoscopic superconducting islands. Our approach synthesizes recent advances in materials growth with tools commonly used in quantum-dot experiments, including gate control of tunnel barriers and Coulomb effects, charge sensing, and charge pumping. We outline a sequence of milestones interpolating between zero-mode detection and quantum computing that includes (1 detection of fusion rules for non-Abelian anyons using either proximal charge sensors or pumped current, (2 validation of a prototype topological qubit, and (3 demonstration of non-Abelian statistics by braiding in a branched geometry. The first two milestones require only a single wire with two islands, and additionally enable sensitive measurements of the system’s excitation gap, quasiparticle poisoning rates, residual Majorana zero-mode splittings, and topological-qubit coherence times. These pre-braiding experiments can be adapted to other manipulation and read out schemes as well.

  4. The epidemiological transition in Antananarivo, Madagascar: an assessment based on death registers (1900–2012

    Directory of Open Access Journals (Sweden)

    Bruno Masquelier

    2014-05-01

    Full Text Available Background: Madagascar today has one of the highest life expectancies in sub-Saharan Africa, despite being among the poorest countries in the continent. There are relatively few detailed accounts of the epidemiological transition in this country due to the lack of a comprehensive death registration system at the national level. However, in Madagascar's capital city, death registration was established around the start of the 20th century and is now considered virtually complete. Objective: We provide an overview of trends in all-cause and cause-specific mortality in Antananarivo to document the timing and pace of the mortality decline and the changes in the cause-of-death structure. Design: Death registers covering the period 1976–2012 were digitized and the population at risk of dying was estimated from available censuses and surveys. Trends for the period 1900–1976 were partly reconstructed from published sources. Results: The crude death rate stagnated around 30‰ until the 1940s in Antananarivo. Mortality declined rapidly after the World War II and then resurged again in the 1980s as a result of the re-emergence of malaria and the collapse of Madagascar's economy. Over the past 30 years, impressive gains in life expectancy have been registered thanks to the unabated decline in child mortality, despite political instability, a lasting economic crisis and the persistence of high rates of chronic malnutrition. Progress in adult survival has been more modest because reductions in infectious diseases and diseases of the respiratory system have been partly offset by increases in cardiovascular diseases, neoplasms, and other diseases, particularly at age 50 years and over. Conclusions: The transition in Antananarivo has been protracted and largely dependent on anti-microbial and anti-parasitic medicine. The capital city now faces a double burden of communicable and non-communicable diseases. The ongoing registration of deaths in the capital

  5. Morbidity before and after the Diagnosis of Hyperthyroidism: A Nationwide Register-Based Study

    Science.gov (United States)

    Brandt, Frans; Thvilum, Marianne; Almind, Dorthe; Christensen, Kaare; Green, Anders; Hegedüs, Laszlo; Brix, Thomas Heiberg

    2013-01-01

    Background Hyperthyroidism has been linked with different morbidities, like atrial fibrillation, stroke and diabetes mellitus. However, our knowledge regarding the extent and temporal relation between hyperthyroidism and other diseases is fragmented. Here, we aimed at evaluating various morbidities before and after the diagnosis of hyperthyroidism. Methods Observational cohort study. From nationwide Danish health registers 2631 hyperthyroid singletons and 375 twin pairs discordant for hyperthyroidism were identified and followed for an average of 6 years (range 0–13). Data on the occurrence of cardiovascular diseases, lung diseases, diabetes mellitus, rheumatic diseases and malignant diseases was obtained by person-to-person record linkage with the National Danish Patient Register and/or the Danish National Prescription Registry (lung diseases and diabetes mellitus). Logistic and Cox regression models were used to assess the risk of morbidity before and after the diagnosis of hyperthyroidism, respectively. All Cox regression analyses were adjusted for the degree of co-morbidity preceding the diagnosis of hyperthyroidism, using the Charlson score. Results Hyperthyroid individuals had a significantly higher risk of being diagnosed with cardiovascular diseases (odds ratio (OR) 1.65; 95% confidence interval (CI): 1.45–1.87), lung diseases (OR 1.53; 95% CI: 1.29–1.60), and diabetes mellitus (OR 1.43, 95% CI: 1.20–1.72), but not with malignant diseases (OR 1.16, 95% CI: 0.99–1.36) prior to the diagnosis of hyperthyroidism. After the diagnosis of hyperthyroidism, subjects had a significantly higher risk of being diagnosed with cardiovascular diseases (hazard ratio (HR) 1.34; 95% CI: 1.15–1.56), lung diseases (HR 1.28; 95% CI: 1.10–1.49), and diabetes mellitus (HR 1.46; 95% CI: 1.16–1.84), but not with rheumatic diseases (HR 1.39, 95% CI: 0.92–2.09) or malignant diseases (HR 1.18, 95% CI 0.97–1.42). Conclusions We demonstrate a significantly increased

  6. Local field effects and metamaterials based on colloidal quantum dots

    International Nuclear Information System (INIS)

    Porvatkina, O V; Tishchenko, A A; Strikhanov, M N

    2015-01-01

    Metamaterials are composite structures that exhibit interesting and unusual properties, e.g. negative refractive index. In this article we consider metamaterials based on colloidal quantum dots (CQDs). We investigate these structures taking into account the local field effects and theoretically analyze expressions for permittivity and permeability of metamaterials based on CdSe CQDs. We obtain inequality describing the conditions when material with definite concentration of CQDs is metamaterial. Also we investigate how the values of dielectric polarizability and magnetic polarizability of CQDs depend on the dots radius and properties the material the quantum dots are made of. (paper)

  7. Ranking REACH registered neutral, ionizable and ionic organic chemicals based on their aquatic persistency and mobility.

    Science.gov (United States)

    Arp, H P H; Brown, T N; Berger, U; Hale, S E

    2017-07-19

    The contaminants that have the greatest chances of appearing in drinking water are those that are mobile enough in the aquatic environment to enter drinking water sources and persistent enough to survive treatment processes. Herein a screening procedure to rank neutral, ionizable and ionic organic compounds for being persistent and mobile organic compounds (PMOCs) is presented and applied to the list of industrial substances registered under the EU REACH legislation as of December 2014. This comprised 5155 identifiable, unique organic structures. The minimum cut-off criteria considered for PMOC classification herein are a freshwater half-life >40 days, which is consistent with the REACH definition of freshwater persistency, and a log D oc water distribution coefficient). Experimental data were given the highest priority, followed by data from an array of available quantitative structure-activity relationships (QSARs), and as a third resort, an original Iterative Fragment Selection (IFS) QSAR. In total, 52% of the unique REACH structures made the minimum criteria to be considered a PMOC, and 21% achieved the highest PMOC ranking (half-life > 40 days, log D oc freshwater persistency, which was also the parameter that QSARs performed the most poorly at predicting. Several prioritized drinking water contaminants in the EU and USA, and other contaminants of concern, were identified as PMOCs. This identification and ranking procedure for PMOCs can be part of a strategy to better identify contaminants that pose a threat to drinking water sources.

  8. Umbilical cord length in singleton gestations: a Finnish population-based retrospective register study.

    Science.gov (United States)

    Georgiadis, L; Keski-Nisula, L; Harju, M; Räisänen, S; Georgiadis, S; Hannila, M-L; Heinonen, S

    2014-04-01

    Many complications of pregnancy and delivery are associated with umbilical cord length. It is important to examine the variation in length, in order to identify normal and abnormal conditions. Moreover, the factors influencing cord growth and development are not precisely known. The main objectives were to provide updated reference charts for umbilical cord length in singleton pregnancies and to evaluate potential factors affecting cord length. Birth register data of 47,284 singleton pregnant women delivering in Kuopio University Hospital, Finland was collected prospectively. Gender-specific centile charts for cord length from 22 to 44 gestational weeks were obtained using generalized additive models for location, scale, and shape (GAMLSS). Gestational, fetal, and maternal factors were studied for their potential influence on cord length with single variable analysis and stepwise multiple linear regression analysis. Cord length increased according to gestational age, while the growth decelerated post-term. Birth weight, placental weight, pregravid maternal body mass index, parity, and maternal age correlated to cord length. Gestational diabetes and previous miscarriages were associated with longer cords, while female gender and placental abruption were associated with shorter cords. Girls had shorter cords throughout gestation although there was substantial variation in length in both genders. Cord length associated significantly with birth weight, placental weight, and gestational age. Significantly shorter cords were found in women with placental abruption. This important finding requires further investigation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. An Improved Quantum Information Hiding Protocol Based on Entanglement Swapping of χ-type Quantum States

    International Nuclear Information System (INIS)

    Xu Shu-Jiang; Wang Lian-Hai; Ding Qing-Yan; Zhang Shu-Hui; Chen Xiu-Bo

    2016-01-01

    In 2011, Qu et al. proposed a quantum information hiding protocol based on the entanglement swapping of χ-type quantum states. Because a χ-type state can be described by the 4-particle cat states which have good symmetry, the possible output results of the entanglement swapping between a given χ-type state and all of the 16 χ-type states are divided into 8 groups instead of 16 groups of different results when the global phase is not considered. So it is difficult to read out the secret messages since each result occurs twice in each line (column) of the secret messages encoding rule for the original protocol. In fact, a 3-bit instead of a 4-bit secret message can be encoded by performing two unitary transformations on 2 particles of a χ-type quantum state in the original protocol. To overcome this defect, we propose an improved quantum information hiding protocol based on the general term formulas of the entanglement swapping among χ-type states. (paper)

  10. Quantum Cryptography Based on the Deutsch-Jozsa Algorithm

    Science.gov (United States)

    Nagata, Koji; Nakamura, Tadao; Farouk, Ahmed

    2017-09-01

    Recently, secure quantum key distribution based on Deutsch's algorithm using the Bell state is reported (Nagata and Nakamura, Int. J. Theor. Phys. doi: 10.1007/s10773-017-3352-4, 2017). Our aim is of extending the result to a multipartite system. In this paper, we propose a highly speedy key distribution protocol. We present sequre quantum key distribution based on a special Deutsch-Jozsa algorithm using Greenberger-Horne-Zeilinger states. Bob has promised to use a function f which is of one of two kinds; either the value of f( x) is constant for all values of x, or else the value of f( x) is balanced, that is, equal to 1 for exactly half of the possible x, and 0 for the other half. Here, we introduce an additional condition to the function when it is balanced. Our quantum key distribution overcomes a classical counterpart by a factor O(2 N ).

  11. Social capital and frequent attenders in general practice: a register-based cohort study.

    Science.gov (United States)

    Pasgaard, Alexander A; Mæhlisen, Maiken H; Overgaard, Charlotte; Ejlskov, Linda; Torp-Pedersen, Christian; Bøggild, Henrik

    2018-03-02

    Frequent attendance to primary care constitutes a large use of resources for the health care system. The association between frequent attendance and illness-related factors has been examined in several studies, but little is known about the association between frequent attendance and individual social capital. The aim of this study is to explore this association. The analysis is conducted on responders to the North Denmark Region Health Profile 2010 (n = 23,384), individually linked with information from administrative registers. Social capital is operationalized at the individual level, and includes cognitive (interpersonal trust and norms of reciprocity) as well as structural (social network and civic engagement) dimensions. Frequent attendance is defined as the upper-quartile of the total number of measured consultations with a general practitioner over a period of 148 weeks. Using multiple logistic regression, we found that frequent attendance was associated with a lower score in interpersonal trust [OR 0.86 (0.79-0.94)] and social network [OR 0.88 (0.79-0.98)] for women, when adjusted for age, education, income and SF12 health scores. Norms of reciprocity and civic engagement were not significantly associated with frequent attendance for women [OR 1.05 (0.99-1.11) and OR 1.01 (0.92-1.11) respectively]. None of the associations were statistically significant for men. This study suggests that for women, some aspects of social capital are associated with frequent attendance in general practice, and the statistically significant dimensions belonged to both cognitive and structural aspects of social capital. This association was not seen for men. This indicates a multifaceted and heterogeneous relationship between social capital and frequent attendance among genders.

  12. Risk factors of coercion among psychiatric inpatients: a nationwide register-based cohort study.

    Science.gov (United States)

    Thomsen, Christoffer; Starkopf, Liis; Hastrup, Lene Halling; Andersen, Per Kragh; Nordentoft, Merete; Benros, Michael Eriksen

    2017-08-01

    Reducing the use of coercion among patients with mental disorders has long been a political priority. However, risk factors for coercive measures have primarily been investigated in smaller studies. To reduce the use of coercion, it is crucial to identify people at risk which we aim to do in this first large-scale study. A cohort study was conducted among all psychiatric inpatients in Denmark, following 112,233 individuals during 1999-2014. Data from Danish registers were analysed using logistic regression for repeated measures. 24,594 inpatients were exposed to a coercive measure (21.9%). Clinical characteristics were the foremost predictors of coercion and patients with organic mental disorder had the highest increased risk of being subjected to a coercive measure (OR = 5.56; 95% CI = 5.04, 6.14). The risk of coercion was the highest in the first admission and decreased with the number of admissions (all p < 0.001). The following socioeconomic variables were associated with an increased risk of coercion: male sex, unemployment, lower social class and immigrants from low and middle income countries (all p < 0.001). Early retirement and social relations, such as being married and having children, reduced the risk of being subjected to coercive measure (all p < 0.05). From our nationwide data, we identified a broad range of risk factors associated with coercive measures. Our findings can assist researchers in identifying patients at risk of coercion and thereby help targeting new coercion reduction programs.

  13. A register based epidemiological description of risk factors and outcomes for major psychiatric disorders, focusing on a comparison between bipolar affective disorder and schizophrenia

    DEFF Research Database (Denmark)

    Laursen, Thomas Munk

    2006-01-01

    of schizophrenia and bipolar affective disorder. The studies were based on four Danish registers: the Psychiatric Central Register, the Danish Civil Registration System, the Cause of Death Register, and the Danish Medical Birth Register. From the registers, large population based cohorts were identified...... and followed over several decades. Survival analysis techniques were applied to identify risk factors and mortality rates. The results demonstrated an overlap in risk factors for schizophrenia and bipolar affective disorder. Excess mortality (compared to persons never admitted with a psychiatric disorder......), and environmental factors act (or interact) with this predisposition. However, large differences in gender distribution and age at onset are present, and differences and similarities between the disorders should be further examined before the Kraepelinian dichotomization can be disregarded....

  14. An Online Banking System Based on Quantum Cryptography Communication

    Science.gov (United States)

    Zhou, Ri-gui; Li, Wei; Huan, Tian-tian; Shen, Chen-yi; Li, Hai-sheng

    2014-07-01

    In this paper, an online banking system has been built. Based on quantum cryptography communication, this system is proved unconditional secure. Two sets of GHZ states are applied, which can ensure the safety of purchase and payment, respectively. In another word, three trading participants in each triplet state group form an interdependent and interactive relationship. In the meantime, trading authorization and blind signature is introduced by means of controllable quantum teleportation. Thus, an effective monitor is practiced on the premise that the privacy of trading partners is guaranteed. If there is a dispute or deceptive behavior, the system will find out the deceiver immediately according to the relationship mentioned above.

  15. Universal Quantum Transducers Based on Surface Acoustic Waves

    NARCIS (Netherlands)

    Schuetz, M.J.A.; Kessler, E.M.; Giedke, G.; Vandersypen, L.M.K.; Lukin, M.D.; Cirac, J.I.

    2015-01-01

    We propose a universal, on-chip quantum transducer based on surface acoustic waves in piezoactive materials. Because of the intrinsic piezoelectric (and/or magnetostrictive) properties of the material, our approach provides a universal platform capable of coherently linking a broad array of qubits,

  16. Quantum

    CERN Document Server

    Al-Khalili, Jim

    2003-01-01

    In this lively look at quantum science, a physicist takes you on an entertaining and enlightening journey through the basics of subatomic physics. Along the way, he examines the paradox of quantum mechanics--beautifully mathematical in theory but confoundingly unpredictable in the real world. Marvel at the Dual Slit experiment as a tiny atom passes through two separate openings at the same time. Ponder the peculiar communication of quantum particles, which can remain in touch no matter how far apart. Join the genius jewel thief as he carries out a quantum measurement on a diamond without ever touching the object in question. Baffle yourself with the bizzareness of quantum tunneling, the equivalent of traveling partway up a hill, only to disappear then reappear traveling down the opposite side. With its clean, colorful layout and conversational tone, this text will hook you into the conundrum that is quantum mechanics.

  17. Multimorbidity and Its Patterns according to Immigrant Origin. A Nationwide Register-Based Study in Norway.

    Directory of Open Access Journals (Sweden)

    Esperanza Diaz

    Full Text Available As the flows of immigrant populations increase worldwide, their heterogeneity becomes apparent with respect to the differences in the prevalence of chronic physical and mental disease. Multimorbidity provides a new framework in understanding chronic diseases holistically as the consequence of environmental, social, and personal risks that contribute to increased vulnerability to a wide variety of illnesses. There is a lack of studies on multimorbidity among immigrants compared to native-born populations.This nationwide multi-register study in Norway enabled us i to study the associations between multimorbidity and immigrant origin, accounting for other known risk factors for multimorbidity such as gender, age and socioeconomic levels using logistic regression analyses, and ii to identify patterns of multimorbidity in Norway for immigrants and Norwegian-born by means of exploratory factor analysis technique.Multimorbidity rates were lower for immigrants compared to Norwegian-born individuals, with unadjusted odds ratios (OR and 95% confidence intervals 0.38 (0.37-0.39 for Eastern Europe, 0.58 (0.57-0.59 for Asia, Africa and Latin America, and 0.67 (0.66-0.68 for Western Europe and North America. Results remained significant after adjusting for socioeconomic factors. Similar multimorbidity disease patterns were observed among Norwegian-born and immigrants, in particular between Norwegian-born and those from Western European and North American countries. However, the complexity of patterns that emerged for the other immigrant groups was greater. Despite differences observed in the development of patterns with age, such as ischemic heart disease among immigrant women, we were unable to detect the systematic development of the multimorbidity patterns among immigrants at younger ages.Our study confirms that migrants have lower multimorbidity levels compared to Norwegian-born. The greater complexity of multimorbidity patterns for some immigrant groups

  18. Quantum gyroscope based on Berry phase of spins in diamond

    Science.gov (United States)

    Song, Xuerui; Wang, Liujun; Diao, Wenting; Duan, Chongdi

    2018-02-01

    Gyroscope is the crucial sensor of the inertial navigation system, there is always high demand to improve the sensitivity and reduce the size of the gyroscopes. Using the NV center electronic spin and nuclear spin qubits in diamond, we introduce the research of new types of quantum gyroscopes based on the Berry phase shifts of the spin states during the rotation of the sensor systems. Compared with the performance of the traditional MEMS gyroscope, the sensitivity of the new types of quantum gyroscopes was highly improved and the spatial resolution was reduced to nano-scale. With the help of micro-manufacturing technology in the semiconductor industry, the quantum gyroscopes introduced here can be further integrated into chip-scale sensors.

  19. Multiple exciton generation in quantum dot-based solar cells

    Science.gov (United States)

    Goodwin, Heather; Jellicoe, Tom C.; Davis, Nathaniel J. L. K.; Böhm, Marcus L.

    2018-01-01

    Multiple exciton generation (MEG) in quantum-confined semiconductors is the process by which multiple bound charge-carrier pairs are generated after absorption of a single high-energy photon. Such charge-carrier multiplication effects have been highlighted as particularly beneficial for solar cells where they have the potential to increase the photocurrent significantly. Indeed, recent research efforts have proved that more than one charge-carrier pair per incident solar photon can be extracted in photovoltaic devices incorporating quantum-confined semiconductors. While these proof-of-concept applications underline the potential of MEG in solar cells, the impact of the carrier multiplication effect on the device performance remains rather low. This review covers recent advancements in the understanding and application of MEG as a photocurrent-enhancing mechanism in quantum dot-based photovoltaics.

  20. Quantum synchronization in an optomechanical system based on Lyapunov control.

    Science.gov (United States)

    Li, Wenlin; Li, Chong; Song, Heshan

    2016-06-01

    We extend the concepts of quantum complete synchronization and phase synchronization, which were proposed in A. Mari et al., Phys. Rev. Lett. 111, 103605 (2013)PRLTAO0031-900710.1103/PhysRevLett.111.103605, to more widespread quantum generalized synchronization. Generalized synchronization can be considered a necessary condition or a more flexible derivative of complete synchronization, and its criterion and synchronization measure are proposed and analyzed in this paper. As examples, we consider two typical generalized synchronizations in a designed optomechanical system. Unlike the effort to construct a special coupling synchronization system, we purposefully design extra control fields based on Lyapunov control theory. We find that the Lyapunov function can adapt to more flexible control objectives, which is more suitable for generalized synchronization control, and the control fields can be achieved simply with a time-variant voltage. Finally, the existence of quantum entanglement in different generalized synchronizations is also discussed.

  1. Experimental bit commitment based on quantum communication and special relativity.

    Science.gov (United States)

    Lunghi, T; Kaniewski, J; Bussières, F; Houlmann, R; Tomamichel, M; Kent, A; Gisin, N; Wehner, S; Zbinden, H

    2013-11-01

    Bit commitment is a fundamental cryptographic primitive in which Bob wishes to commit a secret bit to Alice. Perfectly secure bit commitment between two mistrustful parties is impossible through asynchronous exchange of quantum information. Perfect security is however possible when Alice and Bob split into several agents exchanging classical and quantum information at times and locations suitably chosen to satisfy specific relativistic constraints. Here we report on an implementation of a bit commitment protocol using quantum communication and special relativity. Our protocol is based on [A. Kent, Phys. Rev. Lett. 109, 130501 (2012)] and has the advantage that it is practically feasible with arbitrary large separations between the agents in order to maximize the commitment time. By positioning agents in Geneva and Singapore, we obtain a commitment time of 15 ms. A security analysis considering experimental imperfections and finite statistics is presented.

  2. Towards non-conventional methods of designing register-based epidemiological studies: An application to pediatric research.

    Science.gov (United States)

    Gong, Tong; Brew, Bronwyn; Sjölander, Arvid; Almqvist, Catarina

    2017-07-01

    Various epidemiological designs have been applied to investigate the causes and consequences of fetal growth restriction in register-based observational studies. This review seeks to provide an overview of several conventional designs, including cohort, case-control and more recently applied non-conventional designs such as family-based designs. We also discuss some practical points regarding the application and interpretation of family-based designs. Definitions of each design, the study population, the exposure and the outcome measures are briefly summarised. Examples of study designs are taken from the field of low birth-weight research for illustrative purposes. Also examined are relative advantages and disadvantages of each design in terms of assumptions, potential selection and information bias, confounding and generalisability. Kinship data linkage, statistical models and result interpretation are discussed specific to family-based designs. When all information is retrieved from registers, there is no evident preference of the case-control design over the cohort design to estimate odds ratios. All conventional designs included in the review are prone to bias, particularly due to residual confounding. Family-based designs are able to reduce such bias and strengthen causal inference. In the field of low birth-weight research, family-based designs have been able to confirm a negative association not confounded by genetic or shared environmental factors between low birth weight and the risk of asthma. We conclude that there is a broader need for family-based design in observational research as evidenced by the meaningful contributions to the understanding of the potential causal association between low birth weight and subsequent outcomes.

  3. Quantum Instantons and Quantum Chaos

    OpenAIRE

    Jirari, H.; Kröger, H.; Luo, X. Q.; Moriarty, K. J. M.; Rubin, S. G.

    1999-01-01

    Based on a closed form expression for the path integral of quantum transition amplitudes, we suggest rigorous definitions of both, quantum instantons and quantum chaos. As an example we compute the quantum instanton of the double well potential.

  4. Graphene-based superconducting quantum point contacts

    International Nuclear Information System (INIS)

    Moghaddam, A.G.; Zareyan, M.

    2007-01-01

    We investigate the Josephson effect in the graphene nanoribbons of length L smaller than the superconducting coherence length and an arbitrary width W. We find that in contrast to an ordinary superconducting quantum point contact (SQPC), the critical supercurrent I c is not quantized for the nanoribbons with smooth and armchair edges. For a low concentration of the carriers, I c decreases monotonically with lowering W/L and tends to a constant minimum for a narrow nanoribbon with W c is zero for the smooth edges but eΔ 0 /ℎ for the armchair edges. At higher concentrations of the carriers this monotonic variation acquires a series of peaks. Further analysis of the current-phase relation and the Josephson coupling strength I c R N in terms of W/L and the concentration of carriers revels significant differences with those of an ordinary SQPC. On the other hand for a zigzag nanoribbon, we find that, similar to an ordinary SQPC, I c is quantized but to the half-integer values (n+1/2)4eΔ 0 /ℎ. (orig.)

  5. Factors Associated with Enhanced Gross Motor Progress in Children with Cerebral Palsy: A Register-Based Study.

    Science.gov (United States)

    Størvold, Gunfrid V; Jahnsen, Reidun B; Evensen, Kari Anne I; Romild, Ulla K; Bratberg, Grete H

    2018-05-01

    To examine associations between interventions and child characteristics; and enhanced gross motor progress in children with cerebral palsy (CP). Prospective cohort study based on 2048 assessments of 442 children (256 boys, 186 girls) aged 2-12 years registered in the Cerebral Palsy Follow-up Program and the Cerebral Palsy Register of Norway. Gross motor progress estimates were based on repeated measures of reference percentiles for the Gross Motor Function Measure (GMFM-66) in a linear mixed model. Mean follow-up time: 2.9 years. Intensive training was the only intervention factor associated with enhanced gross motor progress (mean 3.3 percentiles, 95% CI: 1.0, 5.5 per period of ≥3 sessions per week and/or participation in an intensive program). Gross motor function was on average 24.2 percentiles (95% CI: 15.2, 33.2) lower in children with intellectual disability compared with others. Except for eating problems (-10.5 percentiles 95% CI: -18.5, -2.4) and ankle contractures by age (-1.9 percentiles 95% CI: -3.6, -0.2) no other factors examined were associated with long-term gross motor progress. Intensive training was associated with enhanced gross motor progress over an average of 2.9 years in children with CP. Intellectual disability was a strong negative prognostic factor. Preventing ankle contractures appears important for gross motor progress.

  6. Differences in cervical cancer screening between immigrants and nonimmigrants in Norway: a primary healthcare register-based study.

    Science.gov (United States)

    Møen, Kathy A; Kumar, Bernadette; Qureshi, Samera; Diaz, Esperanza

    2017-11-01

    The prevalence of cervical cancer is high among some groups of immigrants. Although there is evidence of low participation in cervical cancer screening programs among immigrants, studies have been subject to selection bias and accounted for few immigrant groups. The aim of this study was to compare the proportion of several groups of immigrants versus nonimmigrants attending the cervical cancer-screening program in Norway. In addition, we aimed to study predictors for attendance to the screening program. Register-based study using merged data from four national registries. All Norwegian-born women (1 168 832) and immigrant women (152 800) of screening age for cervical cancer (25-69 years) registered in Norway in 2008 were included. We grouped the immigrants by world's geographic region and carried out descriptive analyses and constructed several logistic regression models. The main outcome variable was whether the woman was registered with a Pap smear in 2008 or not. Immigrants had lower rates of participation compared with Norwegian-born women; Western Europe [adjusted odds ratio (OR), 95% confidence interval (CI): 0.84, 0.81-0.88], Eastern Europe (OR 0.64, 95% CI: 0.60-0.67), Asia (OR 0.74, 95% CI: 0.71-0.77), Africa (OR 0.61, 95% CI: 0.56-0.67) and South America (OR 0.87, 95% CI: 0.79-0.96). Younger age, higher income, residence in rural areas, and having a female general practitioner (GP) were associated with Pap smear. Longer residential time in Norway and having a nonimmigrant GP were associated with screening for some immigrant groups. Appropriate interventions targeting both immigrants and GPs need to be developed and evaluated.

  7. Early-onset inguinal hernia as risk factor for schizophrenia or related psychosis: a nationwide register-based cohort study.

    Science.gov (United States)

    Melkersson, Kristina; Wernroth, Mona-Lisa

    2017-10-01

    In an earlier interview study, we found that more men with familial schizophrenia had undergone inguinal hernia operation, than men with sporadic schizophrenia. However, there are no other studies published specifically on inguinal hernia and schizophrenia. Therefore, the aim of this study was to carry out a Swedish register-based cohort study on the association between inguinal hernia and schizophrenia or related psychosis. Data from the Total Population- and Medical Birth-Registers were used to create a cohort of all individuals born in Sweden 1987-1999 (n=1 406 168). The cohort individuals were linked with the In- and Out-patient Registers and followed from birth to 2015 to identify onset of schizophrenia, schizoaffective disorder and inguinal hernia. Cox proportional hazards regression models were used to assess the association between inguinal hernia before age 13 and risk of developing schizophrenia or schizoaffective disorder during a follow-up from age 13. Inguinal hernia before age 13 was identified in 21 095 individuals, and during the follow-up in total 1314 individuals developed schizophrenia or schizoaffective disorder. The risk of schizophrenia or schizoaffective disorder was higher among individuals with inguinal hernia before age 13, than among individuals without such a diagnosis, especially among the men [adjusted hazard ratio (95% confidence interval); all: 1.44 (1.01-2.06), p=0.0452, men: 1.46 (1.01-2.12), p=0.0460, women: 0.56 (0.14-2.27), p=0.4173]. This study shows that early-onset inguinal hernia is associated with increased risk of developing schizophrenia or schizoaffective disorder, especially in men. Such an association may point to a common biological basis for the development of inguinal hernia and schizophrenia or related psychosis.

  8. An endohedral fullerene-based nuclear spin quantum computer

    International Nuclear Information System (INIS)

    Ju Chenyong; Suter, Dieter; Du Jiangfeng

    2011-01-01

    We propose a new scalable quantum computer architecture based on endohedral fullerene molecules. Qubits are encoded in the nuclear spins of the endohedral atoms, which posses even longer coherence times than the electron spins which are used as the qubits in previous proposals. To address the individual qubits, we use the hyperfine interaction, which distinguishes two modes (active and passive) of the nuclear spin. Two-qubit quantum gates are effectively implemented by employing the electronic dipolar interaction between adjacent molecules. The electron spins also assist in the qubit initialization and readout. Our architecture should be significantly easier to implement than earlier proposals for spin-based quantum computers, such as the concept of Kane [B.E. Kane, Nature 393 (1998) 133]. - Research highlights: → We propose an endohedral fullerene-based scalable quantum computer architecture. → Qubits are encoded on nuclear spins, while electron spins serve as auxiliaries. → Nuclear spins are individually addressed using the hyperfine interaction. → Two-qubit gates are implemented through the medium of electron spins.

  9. Optimal attacks on qubit-based Quantum Key Recycling

    Science.gov (United States)

    Leermakers, Daan; Škorić, Boris

    2018-03-01

    Quantum Key Recycling (QKR) is a quantum cryptographic primitive that allows one to reuse keys in an unconditionally secure way. By removing the need to repeatedly generate new keys, it improves communication efficiency. Škorić and de Vries recently proposed a QKR scheme based on 8-state encoding (four bases). It does not require quantum computers for encryption/decryption but only single-qubit operations. We provide a missing ingredient in the security analysis of this scheme in the case of noisy channels: accurate upper bounds on the required amount of privacy amplification. We determine optimal attacks against the message and against the key, for 8-state encoding as well as 4-state and 6-state conjugate coding. We provide results in terms of min-entropy loss as well as accessible (Shannon) information. We show that the Shannon entropy analysis for 8-state encoding reduces to the analysis of quantum key distribution, whereas 4-state and 6-state suffer from additional leaks that make them less effective. From the optimal attacks we compute the required amount of privacy amplification and hence the achievable communication rate (useful information per qubit) of qubit-based QKR. Overall, 8-state encoding yields the highest communication rates.

  10. Higher-dimensional orbital-angular-momentum-based quantum key distribution with mutually unbiased bases

    CSIR Research Space (South Africa)

    Mafu, M

    2013-09-01

    Full Text Available We present an experimental study of higher-dimensional quantum key distribution protocols based on mutually unbiased bases, implemented by means of photons carrying orbital angular momentum. We perform (d + 1) mutually unbiased measurements in a...

  11. Status and prospects of radioecological data base for State register of individuals exposed to radiation as a result of ChNPP accident

    International Nuclear Information System (INIS)

    Tsyb, A.F.; Pitkevich, V.A.; Duba, V.V.; Ivanov, V.K.

    1992-01-01

    Radiation ecology register for radioecological data base is being elaborated. The basic components of register are as follows: the basis of the initial documents according to districts and inhabitated localities; software for the data analysis and processing; software for implementation of physical models of radionuclide behaviour in the environment and absorbed dose formation; radioecological certificates (passports) for inhabitated localities and regions; software for evaluating the individual radiation loads induced by various radiation factors according to the requirements made by the Russian State medico-dosimetric register; data base. 2 refs.; 3 figs

  12. Differences in primary health care use among sub-Saharan African immigrants in Norway: a register-based study.

    Science.gov (United States)

    Diaz, Esperanza; Mbanya, Vivian N; Gele, Abdi A; Kumar, Bernadette

    2017-07-28

    Immigrants' utilization of primary health care (PHC) services differs from that of the host populations. However, immigrants are often classified in broad groups by continent of origin, and the heterogeneity within the same continent may hide variation in use among immigrant groups at a national level. Differences in utilization of PHC between sub-Saharan African immigrants have not received much attention. Registry-based study using merged data from the National Population Register and the Norwegian Health Economics Administration. African immigrants and their descendants registered in Norway in 2008 (36,366 persons) where included in this study. Using χ 2 test and logistic regression models, we assessed the differences in the use of PHC, including general practitioner (GP) and emergency room (ER) services, and the distribution of morbidity burden for immigrants from Somalia, Ethiopia, Eritrea, and Gambia. For the analyses, we used the number of visits and medical diagnoses from each consultation registered by the physician. Among the total studied population, 66.1% visited PHC within 1 year. The diagnoses registered were similar for all four immigrants groups, regardless of country of origin. Compared to immigrants from Somalia, the age and sex adjusted odds ratios (OR) for use of GP were significantly lower for Ethiopians (OR 0.91; 0.86-0.97), Eritreans (OR 0.85; 0.79-0.91), and Gambians (OR 0.88; 0.80-0.97). Similarly, we also observed lower use of ER among Ethiopians (OR 0.88; 0.81-0.95), Eritreans (OR 0.56; 0.51-0.62) and Gambians (OR 0.81; 0.71-0.92). However, immigrants from Somalia reduced their use of PHC with longer duration of stay in Norway. Differences between groups persisted after further adjustment for employment status. Despite the similarities in diagnoses among the sub-Saharan African immigrant groups in Norway, their use of PHC services differs by country of origin and length of stay. It is important to assess the reasons for the differences

  13. Quantum key distribution using card, base station and trusted authority

    Energy Technology Data Exchange (ETDEWEB)

    Nordholt, Jane E.; Hughes, Richard John; Newell, Raymond Thorson; Peterson, Charles Glen; Rosenberg, Danna; McCabe, Kevin Peter; Tyagi, Kush T.; Dallmann, Nicholas

    2017-06-14

    Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trust authority. The keys can be used to set up secure communication, for authentication, for access control, or for other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.

  14. Quantum key distribution using card, base station and trusted authority

    Science.gov (United States)

    Nordholt, Jane Elizabeth; Hughes, Richard John; Newell, Raymond Thorson; Peterson, Charles Glen; Rosenberg, Danna; McCabe, Kevin Peter; Tyagi, Kush T; Dallman, Nicholas

    2015-04-07

    Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trusted authority. The keys can be used to set up secure communication, for authentication, for access control, or for other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.

  15. A Method to Estimate Energy Demand in Existing Buildings Based on the Danish Building and Dwellings Register (BBR)

    DEFF Research Database (Denmark)

    Nielsen, Anker; Bertelsen, Niels Haldor; Wittchen, Kim Bjarne

    2013-01-01

    an energy label. The Danish Building Research Institute has described a method that can be used to estimate the energy demand in buildings specially dwellings. This is based on the information in the Danish Building and Dwelling Register (BBR) and information on building regulations at construction year......The Energy Performance Directive requires energy certifications for buildings. This is implemented in Denmark so that houses that are sold must have an energy performance label based on an evaluation from a visit to the building. The result is that only a small part of the existing houses has...... for the house. The result is an estimate for energy demand in each building with a variation. This makes it possible to make an automatic classification of all buildings. Then it is possible to find houses in need for thermal improvements. This method is tested for single family houses and flats. The paper...

  16. Family history of psychiatric illness as a risk factor for schizoaffective disorder: a Danish register-based cohort study

    DEFF Research Database (Denmark)

    Laursen, Thomas Munk; Labouriau, Rodrigo; Licht, Rasmus W

    2005-01-01

    BACKGROUND: Schizoaffective disorder may be related to both schizophrenia and bipolar disorders, but no population-based studies, to our knowledge, have investigated this association in families. OBJECTIVES: To determine whether a psychiatric history of schizoaffective disorder, bipolar disorder......, or schizophrenia among parents and siblings is a risk factor for developing a schizoaffective disorder, and whether a specific pattern of family history of psychiatric illness exists in persons with schizoaffective disorder compared with persons with bipolar disorder or schizophrenia. DESIGN: Register-based cohort...... study. SETTING: Denmark. COHORT: The 2.4 million persons born in Denmark after 1952. MAIN OUTCOME MEASURES: Relative risks of the 3 illnesses estimated by Poisson regression. RESULTS: In total, 1925 persons had a schizoaffective disorder, 3721 had a bipolar disorder, and 12 501 had schizophrenia...

  17. Hypothyroidism is a predictor of disability pension and loss of labor market income: a Danish register-based study.

    Science.gov (United States)

    Thvilum, Marianne; Brandt, Frans; Brix, Thomas Heiberg; Hegedüs, Laszlo

    2014-09-01

    Hypothyroidism is associated with an increased somatic and psychiatric disease burden. Whether there are any socioeconomic consequences of hypothyroidism, such as early retirement or loss of income, remains unclarified. Our aim was to examine, compared with a matched control group, the risk of receiving disability pension (before the age of 60) and the effect on labor market income in patients diagnosed with hypothyroidism. This was an observational register-based cohort study. By record linkage between different Danish health registers, 1745 hypothyroid singletons diagnosed before the age of 60 were each matched with 4 non-hypothyroid controls and followed for a mean of 5 (range 1-31) years. Additionally, we included 277 same-sex twin pairs discordant for hypothyroidism. The risk of disability pension was evaluated by the Cox regression analysis. Changes in labor market income progression over 5 years were evaluated using a difference in difference model. With a hazard ratio of 2.24 (95% confidence interval = 1.73-2.89), individuals diagnosed with hypothyroidism had a significantly increased risk of disability pension. This remained significant when adjusting for educational level and comorbidity (hazard ratio = 1.89; 95% confidence interval = 1.42-2.51). In an analysis of labor market income, 2 years before compared with 2 years after the diagnosis of hypothyroidism, the hypothyroid individuals had on average a €1605 poorer increase than their euthyroid controls (P pension.

  18. Multi-strategy based quantum cost reduction of linear nearest-neighbor quantum circuit

    Science.gov (United States)

    Tan, Ying-ying; Cheng, Xue-yun; Guan, Zhi-jin; Liu, Yang; Ma, Haiying

    2018-03-01

    With the development of reversible and quantum computing, study of reversible and quantum circuits has also developed rapidly. Due to physical constraints, most quantum circuits require quantum gates to interact on adjacent quantum bits. However, many existing quantum circuits nearest-neighbor have large quantum cost. Therefore, how to effectively reduce quantum cost is becoming a popular research topic. In this paper, we proposed multiple optimization strategies to reduce the quantum cost of the circuit, that is, we reduce quantum cost from MCT gates decomposition, nearest neighbor and circuit simplification, respectively. The experimental results show that the proposed strategies can effectively reduce the quantum cost, and the maximum optimization rate is 30.61% compared to the corresponding results.

  19. A novel quantum LSB-based steganography method using the Gray code for colored quantum images

    Science.gov (United States)

    Heidari, Shahrokh; Farzadnia, Ehsan

    2017-10-01

    As one of the prevalent data-hiding techniques, steganography is defined as the act of concealing secret information in a cover multimedia encompassing text, image, video and audio, imperceptibly, in order to perform interaction between the sender and the receiver in which nobody except the receiver can figure out the secret data. In this approach a quantum LSB-based steganography method utilizing the Gray code for quantum RGB images is investigated. This method uses the Gray code to accommodate two secret qubits in 3 LSBs of each pixel simultaneously according to reference tables. Experimental consequences which are analyzed in MATLAB environment, exhibit that the present schema shows good performance and also it is more secure and applicable than the previous one currently found in the literature.

  20. Strengths and weaknesses of Problem Based Learning from the professional perspective of registered nurses

    Directory of Open Access Journals (Sweden)

    María Cónsul-Giribet

    2014-10-01

    Full Text Available OBJECTIVE: to identify competency strengths and weaknesses as perceived by nursing professionals who graduated with a integrated curriculum and competency-based through Problem Based Learning in small groups.METHOD: an intrinsic case study method was used, which analyzes this innovation through former students (from the first class with three years of professional experience. The data were collected through a questionnaire and discussion groups.RESULTS: the results show that their competency level is valued in a very satisfactory manner. This level paradoxically contrasts with the lack of theoretical knowledge they perceived at the end of their education, when they started working in clinical practice.CONCLUSIONS: the teaching strategy was key to motivate an in-depth study and arouse the desire to know. In addition, Problem Based Learning favors and reinforces the decision to learn, which is that necessary in the course of professional life.

  1. Indicators of fetal growth and bipolar disorder: a Danish national register-based study

    DEFF Research Database (Denmark)

    Øgendahl, Bettina; Agerbo, Esben; Byrne, Majella

    2006-01-01

    , controlling for potential confounding factors such as parental age at birth, socio-economic indicators and psychiatric history. We identified 196 cases, and each case was time-, age- and sex-matched with 25 normal population-based controls. All cases were between the ages of 12 and 26 years at the time...

  2. Registered nurses' perception of self-efficacy and competence in smoking cessation after participating in a web-based learning activity.

    Science.gov (United States)

    Rosvall, Annica; Carlson, Elisabeth

    2017-12-01

    To describe how registered nurses having undergone a web-based learning activity perceive their self-efficacy and competence to support patients with smoking cessation in connection with surgery. Smoking cessation in connection with surgery reduces postoperative complications, and the support patients get from registered nurses may be important in helping them become smoke-free in connection with their surgery. Therefore, registered nurses are in need of enhanced understanding about which kind of counselling is the most effective for smoking cessation. Educating large groups of registered nurses in a digital environment appears to be a flexible and cost-effective way. A convergent mixed-method design with data collection was done using questionnaires (n = 47) and semistructured interviews (n = 11). Inclusion criteria were registered nurses in surgical wards. The samples were nonprobability and modified nested. Descriptive statistics and content analysis were used for data analysis. After completing the web-based learning activity, the registered nurses perception was that of good self-efficacy and increased competence in supporting patients with smoking cessation in connection with surgery. They improved their understanding of how to talk about smoking cessation with patients in dialogue using open-ended questions. Nevertheless, the registered nurses requested opportunities for dialogue and interaction with colleagues or topic experts. The results indicate that registered nurses can enhance their competence in supporting patients to embrace smoking cessation by learning in a digital environment. Self-efficacy and understanding of the topic seems to motivate registered nurses to counsel patients about smoking cessation. Findings from this study will be of particular interest to educators in healthcare settings who can devise further development of web-based learning activities. © 2017 John Wiley & Sons Ltd.

  3. Danish registers on aspects of reproduction

    DEFF Research Database (Denmark)

    Blenstrup, Lene Tølbøll; Knudsen, Lisbeth B.

    2011-01-01

    Introduction: The establishing of three Danish population based registers, namely the Fertility Database, the Register of Legally Induced Abortions and the In Vitro Fertilisation register aimed at providing data for surveying of reproductive outcome. Content: The registers include information...... on births, abortions and assisted reproduction as well as selected characteristics of the women (and men) involved. Validity and Coverage: Both the validity and coverage of each register is considered of high quality. Conclusions: These registers provide, both individually and in combination, unique...

  4. Tribological Performance of Some Pennzane(Registered Trademark) Based Greases for Vacuum Applications

    Science.gov (United States)

    Marchetti, Mario; Jones, William R., Jr.; Street, Kenneth W.; Wheeler, Donald; Dixon, Duane; Jansen, Mark J.; Kimura, Hiroshi

    2002-01-01

    Commercial greases for space applications usually fulfill the requirements imposed by the severe conditions of use. The main requirement is their ability to create an EHL film, boundary film, or both under speed, load and temperature conditions that the mechanisms will operate. Three greases, all based on a multiply alkylated cyclopentane (Pennzan(R)) base oil, were studied. The thickeners were an n-octadecylterephthalamate soap, a lithium soap, and a urea derivative. A Four-Ball Tribometer and a Spiral Orbit Tribometer were employed to evaluate the greases under ultrahigh vacuum. Results indicated that all three greases yielded very low wear rates and extended lifetimes. In addition, routine physical property data is reported for each grease.

  5. MITK-based segmentation of co-registered MRI for subject-related regional anesthesia simulation

    Science.gov (United States)

    Teich, Christian; Liao, Wei; Ullrich, Sebastian; Kuhlen, Torsten; Ntouba, Alexandre; Rossaint, Rolf; Ullisch, Marcus; Deserno, Thomas M.

    2008-03-01

    With a steadily increasing indication, regional anesthesia is still trained directly on the patient. To develop a virtual reality (VR)-based simulation, a patient model is needed containing several tissues, which have to be extracted from individual magnet resonance imaging (MRI) volume datasets. Due to the given modality and the different characteristics of the single tissues, an adequate segmentation can only be achieved by using a combination of segmentation algorithms. In this paper, we present a framework for creating an individual model from MRI scans of the patient. Our work splits in two parts. At first, an easy-to-use and extensible tool for handling the segmentation task on arbitrary datasets is provided. The key idea is to let the user create a segmentation for the given subject by running different processing steps in a purposive order and store them in a segmentation script for reuse on new datasets. For data handling and visualization, we utilize the Medical Imaging Interaction Toolkit (MITK), which is based on the Visualization Toolkit (VTK) and the Insight Segmentation and Registration Toolkit (ITK). The second part is to find suitable segmentation algorithms and respectively parameters for differentiating the tissues required by the RA simulation. For this purpose, a fuzzy c-means clustering algorithm combined with mathematical morphology operators and a geometric active contour-based approach is chosen. The segmentation process itself aims at operating with minimal user interaction, and the gained model fits the requirements of the simulation. First results are shown for both, male and female MRI of the pelvis.

  6. Bit-Serial Adder Based on Quantum Dots

    Science.gov (United States)

    Fijany, Amir; Toomarian, Nikzad; Modarress, Katayoon; Spotnitz, Mathew

    2003-01-01

    A proposed integrated circuit based on quantum-dot cellular automata (QCA) would function as a bit-serial adder. This circuit would serve as a prototype building block for demonstrating the feasibility of quantum-dots computing and for the further development of increasingly complex and increasingly capable quantum-dots computing circuits. QCA-based bit-serial adders would be especially useful in that they would enable the development of highly parallel and systolic processors for implementing fast Fourier, cosine, Hartley, and wavelet transforms. The proposed circuit would complement the QCA-based circuits described in "Implementing Permutation Matrices by Use of Quantum Dots" (NPO-20801), NASA Tech Briefs, Vol. 25, No. 10 (October 2001), page 42 and "Compact Interconnection Networks Based on Quantum Dots" (NPO-20855), which appears elsewhere in this issue. Those articles described the limitations of very-large-scale-integrated (VLSI) circuitry and the major potential advantage afforded by QCA. To recapitulate: In a VLSI circuit, signal paths that are required not to interact with each other must not cross in the same plane. In contrast, for reasons too complex to describe in the limited space available for this article, suitably designed and operated QCA-based signal paths that are required not to interact with each other can nevertheless be allowed to cross each other in the same plane without adverse effect. In principle, this characteristic could be exploited to design compact, coplanar, simple (relative to VLSI) QCA-based networks to implement complex, advanced interconnection schemes. To enable a meaningful description of the proposed bit-serial adder, it is necessary to further recapitulate the description of a quantum-dot cellular automation from the first-mentioned prior article: A quantum-dot cellular automaton contains four quantum dots positioned at the corners of a square cell. The cell contains two extra mobile electrons that can tunnel (in the

  7. Sensitivity analysis of the energy demand of existing buildings based on the Danish Building and Dwelling Register (BBR)

    DEFF Research Database (Denmark)

    Nielsen, Anker; Wittchen, Kim Bjarne; Bertelsen, Niels Haldor

    2014-01-01

    performance certificate. The Danish Building Research Institute has described a method that can be applied for estimating the energy demand of dwellings. This is based on the information in the Danish Building and Dwelling Register and requirements in the Danish Building Regulations from the year......The EU Directive on the Energy Performance of Buildings requires that energy certification of buildings should be implemented in Denmark so that houses that are sold or let should have an energy performance certificate. The result is that only a small part of existing houses has an energy...... of construction of the house. The result is an estimate of the energy demand of each building with a variation. This makes it possible to make an automatic classification of all buildings. The paper discusses the uncertainties and makes a sensitivity analysis to find the important parameters. The variations...

  8. Sensitivity analysis of the energy demand of existing buildings based on the Danish Building and Dwelling Register

    DEFF Research Database (Denmark)

    Nielsen, Anker; Wittchen, Kim Bjarne; Bertelsen, Niels Haldor

    2014-01-01

    performance certificate. The Danish Building Research Institute has described a method that can be applied for estimating the energy demand of dwellings. This is based on the information in the Danish Building and Dwelling Register and requirements in the Danish Building Regulations from the year......The EU Directive on the Energy Performance of Buildings requires that energy certification of buildings should be implemented in Denmark so that houses that are sold or let should have an energy performance certificate. The result is that only a small part of existing houses has an energy...... of construction of the house. The result is an estimate of the energy demand of each building with a variation. This makes it possible to make an automatic classification of all buildings. The paper discusses the uncertainties and makes a sensitivity analysis to find the important parameters. The variations...

  9. Associations between patients' risk attitude and their adherence to statin treatment - a population based questionnaire and register study

    DEFF Research Database (Denmark)

    Barfoed, Benedicte Marie Lind; Paulsen, Maja Skov; Christensen, Palle Mark

    2016-01-01

    the risk-averse patients, OR 0.80 (95 %-CI 0.68-0.95) and OR 0.83 (95 %-CI 0.71-0.98), respectively. No significant association was found between adherence and financial risk attitude. Further, patients in the youngest age group and patients with no CVD were less adherent to statin treatment. CONCLUSION......: We find some indication that risk attitude is associated with adherence to statin treatment, and that risk-neutral and risk-seeking patients may have poorer adherence than risk-averse patients. This is important for clinicians to consider when discussing optimal treatment decisions...... on the association between risk attitude and adherence. The aim of the present study was to estimate associations between patients' adherence to statin treatment and different dimensions of risk attitude, and to identify subgroups of patients with poor adherence. METHODS: Population-based questionnaire and register...

  10. The CCC2000 Birth Cohort Study of Register-Based Family History of Mental Disorders and Psychotic Experiences in Offspring

    DEFF Research Database (Denmark)

    Jeppesen, Pia; Tidselbak Larsen, Janne; Clemmensen, Lars

    2015-01-01

    in childhood was predicted by a family history of mental disorder with psychosis rather than a family history of nonpsychotic mental disorder and whether this association differed by severity of PE. The study examined data on 1632 children from a general population birth cohort assessed at age 11-12 years...... by use of a semistructured interview covering 22 psychotic symptoms. The Danish national registers were linked to describe the complete family history of hospital-based psychiatric diagnoses. Uni- and multivariable logistic regressions were used to test whether a family history of any mental disorder...... with psychosis, or of nonpsychotic mental disorder, vs no diagnoses was associated with increased risk of PE in offspring (hierarchical exposure variable). The occurrence of PE in offspring was significantly associated with a history of psychosis among the first-degree relatives (adjusted relative risk [RR] = 3...

  11. Family history of psychiatric illness as a risk factor for schizoaffective disorder: a Danish register-based cohort study

    DEFF Research Database (Denmark)

    Laursen, Thomas Munk; Labouriau, Rodrigo; Licht, Rasmus Wentzer

    2005-01-01

    , or schizophrenia among parents and siblings is a risk factor for developing a schizoaffective disorder, and whether a specific pattern of family history of psychiatric illness exists in persons with schizoaffective disorder compared with persons with bipolar disorder or schizophrenia. DESIGN: Register-based cohort...... study. SETTING: Denmark. COHORT: The 2.4 million persons born in Denmark after 1952. MAIN OUTCOME MEASURES: Relative risks of the 3 illnesses estimated by Poisson regression. RESULTS: In total, 1925 persons had a schizoaffective disorder, 3721 had a bipolar disorder, and 12 501 had schizophrenia....... The relative risk of schizoaffective disorder was 2.76 (95% confidence interval, 2.49-3.06) if a first-degree relative had a history of mental illness compared with a person with no first-degree relatives with such a history. There was an additional risk (95% confidence interval) of 2.57 (2.11-3.13), 3.23 (2...

  12. The impact of self-reported health and register-based prescription medicine purchases on re-employment chances

    DEFF Research Database (Denmark)

    Svane-petersen, Annemette Coop; Dencker-Larsen, Sofie

    2016-01-01

    In this paper, we investigate the influence of self-reported health and register-based prescription medicine purchases on re-employment chances, and whether these health indicators measure similar aspects of health in this analysis. Data came from a 2006 Danish unemployment survey among a random...... on individual prescription medicine purchases for somatic illnesses and prescription medicine purchases for mental illnesses, information on re-employment and various socio-demographic variables. We conducted binary logistic regression analyses to investigate the impact of self-reported health and prescription...... medicine purchases measured in 2006 on re-employment chances in 2007 and 2008. Our analyses show that unemployed workers with poor self-reported health and workers who had prescription medicine purchases for mental illnesses were less likely to be re-employed in 2007 and 2008. Furthermore, the impact...

  13. A cross-disciplinary introduction to quantum annealing-based algorithms

    Science.gov (United States)

    Venegas-Andraca, Salvador E.; Cruz-Santos, William; McGeoch, Catherine; Lanzagorta, Marco

    2018-04-01

    A central goal in quantum computing is the development of quantum hardware and quantum algorithms in order to analyse challenging scientific and engineering problems. Research in quantum computation involves contributions from both physics and computer science; hence this article presents a concise introduction to basic concepts from both fields that are used in annealing-based quantum computation, an alternative to the more familiar quantum gate model. We introduce some concepts from computer science required to define difficult computational problems and to realise the potential relevance of quantum algorithms to find novel solutions to those problems. We introduce the structure of quantum annealing-based algorithms as well as two examples of this kind of algorithms for solving instances of the max-SAT and Minimum Multicut problems. An overview of the quantum annealing systems manufactured by D-Wave Systems is also presented.

  14. Population-based register of acute myocardial infarction: manual of operations

    DEFF Research Database (Denmark)

    Madsen, Mette; Gudnason, Vilmundur; Pajak, Andrzej

    2007-01-01

    (including preventive strategies) and clinical decision making with correct cost-benefit assessments.A stepwise surveillance procedure based on standardized data collection, appropriate record linkage and validation methods was set up by the EUROCISS Project (EUROpean Cardiovascular Indicators Surveillance......Cardiovascular disease is the leading cause of death and hospitalization in both sexes in nearly all countries of Europe. The main forms of cardiovascular disease are ischaemic heart disease and stroke. The magnitude of the problem contrasts with the shortage, weak quality and comparability of data...... available in most European countries.Innovations in medical, invasive and biological treatments have substantially contributed to the escalating costs of health services. It is therefore urgent to obtain reliable information on the magnitude and distribution of the disease for both adequate health planning...

  15. Heritability of Schizophrenia and Schizophrenia Spectrum Based on the Nationwide Danish Twin Register

    DEFF Research Database (Denmark)

    Hilker, Rikke; Helenius, Dorte; Fagerlund, Birgitte

    2018-01-01

    sample. The estimated 79% heritability of SZ is congruent with previous reports and indicates a substantial genetic risk. The high genetic risk also applies to a broader phenotype of SZ spectrum disorders. The low concordance rate of 33% in monozygotic twins demonstrates that illness vulnerability......BACKGROUND: Twin studies have provided evidence that both genetic and environmental factors contribute to schizophrenia (SZ) risk. Heritability estimates of SZ in twin samples have varied methodologically. This study provides updated heritability estimates based on nationwide twin data...... the heritability of SZ to be 79%. When expanding illness outcome to include SZ spectrum disorders, the heritability estimate was almost similar (73%). CONCLUSIONS: The key strength of this study is the application of a novel statistical method accounting for censoring in the follow-up period to a nationwide twin...

  16. Electrochemical degradation of diuron in chloride medium using DSA Registered-Sign based anodes

    Energy Technology Data Exchange (ETDEWEB)

    Pipi, Angelo R. F.; Aquino Neto, Sidney; Andrade, Adalgisa R. de, E-mail: ardandra@ffclrp.usp.br [Departamento de Quimica, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto-SP (Brazil)

    2013-07-15

    This work presents a study of the electrochemical degradation of the herbicide diuron using Ti/Ru{sub x}Ti{sub (1-x)}O{sub 2} and Ti/Ir{sub x}Ti{sub (1-x)}O{sub 2} (x 0.3, 0.5 and 0.7) anodes. The investigation of the degradation was conducted in the presence and in the absence of chloride. The study of the herbicide removal as a function of the current density in the absence of chloride yielded 41 and 49% COD (chemical oxygen demand) removals and 10 and 14% TOC (total organic carbon) removal at 100 mA cm{sup -2}, respectively. By keeping the electrolysis time constant (4 h), Ti/Ru{sub 0.7}Ti{sub 0.3}O{sub 2} anode composition was determined as the most active for removal of diuron and its byproduct. The maximum removal value achieved after 4 h was 58%. Addition of chloride doubled the removal ratio, and 100% COD removal was obtained for Ti/Ru{sub 0.3}Ti{sub 0.7}O{sub 2} . High-performance liquid chromatography (HPLC) analysis confirmed the total removal of the herbicide in chloride medium and indicated the formation of byproducts. The generated byproducts presented as function of the applied current density and the anode composition. Ir-based anodes promoted milder oxidation and furnished more byproducts in aqueous medium. (author)

  17. Parental history of psychiatric diagnoses and unipolar depression: a Danish National Register-based cohort study.

    Science.gov (United States)

    Musliner, K L; Trabjerg, B B; Waltoft, B L; Laursen, T M; Mortensen, P B; Zandi, P P; Munk-Olsen, T

    2015-10-01

    Depression is known to run in families, but the effects of parental history of other psychiatric diagnoses on depression rates are less well studied. Few studies have examined the impact of parental psychopathology on depression rates in older age groups. We established a population-based cohort including all individuals born in Denmark after 1954 and alive on their 10th birthday (N = 29 76 264). Exposure variables were maternal and paternal history of schizophrenia, bipolar disorder, depression, anxiety or 'other' psychiatric diagnoses. Incidence rate ratios (IRRs) were estimated using Poisson regressions. Parental history of any psychiatric diagnosis increased incidence rates of outpatient (maternal: IRR 1.88, p history. IRRs for parental history of non-affective disorders remained relatively stable across age groups, while IRRs for parental affective disorders (unipolar or bipolar) decreased with age from 2.29-3.96 in the youngest age group to 1.53-1.90 in the oldest group. IRR estimates for all parental diagnoses were similar among individuals aged ⩾41 years (IRR range 1.51-1.90). Parental history of any psychiatric diagnosis is associated with increased incidence rates of unipolar depression. In younger age groups, parental history of affective diagnoses is more strongly associated with rates of unipolar depression than non-affective diagnoses; however, this distinction disappears after age 40, suggesting that parental psychopathology in general, rather than any one disorder, confers risk for depression in middle life.

  18. Decoherence and Noise in Spin-based Solid State Quantum Computers. Approximation-Free Numerical Simulations

    National Research Council Canada - National Science Library

    Harmon, Bruce N; Dobrovitski, Viatcheslav V

    2007-01-01

    ...) have also been developed and applied. Most recently, specific strategies for quantum control have been investigated for realistic systems in order to extend the coherence times for spin-based quantum computing implementations...

  19. Developing a MATLAB(registered)-Based Tool for Visualization and Transformation

    Science.gov (United States)

    Anderton, Blake J.

    2003-01-01

    An important step in the structural design and development of spacecraft is the experimental identification of a structure s modal characteristics, such as its natural frequencies and modes of vibration. These characteristics are vital to developing a representative model of any given structure or analyzing the range of input frequencies that can be handled by a particular structure. When setting up such a representative model of a structure, careful measurements using precision equipment (such as accelerometers and instrumented hammers) must be made on many individual points of the structure in question. The coordinate location of each data point is used to construct a wireframe geometric model of the structure. Response measurements obtained from the accelerometers is used to generate the modal shapes of the particular structure. Graphically, this is displayed as a combination of the ways a structure will ideally respond to a specified force input. Two types of models of the tested structure are often used in modal analysis: an analytic model showing expected behavior of the structure, and an experimental model showing measured results due to observed phenomena. To evaluate the results from the experimental model, a comparison of analytic and experimental results must be made between the two models. However, comparisons between these two models become difficult when the two coordinate orientations differ in a manner such that results are displayed in an unclear fashion. Such a problem proposes the need for a tool that not only communicates a graphical image of a structure s wireframe geometry based on various measurement locations (called nodes), but also allows for a type of transformation of the image s coordinate geometry so that a model s coordinate orientation is made to match the orientation of another model. Such a tool should also be designed so that it is able to construct coordinate geometry based on many different listings of node locations and is able

  20. Mode of delivery and the probability of subsequent childbearing: a population-based register study.

    Science.gov (United States)

    Elvander, C; Dahlberg, J; Andersson, G; Cnattingius, S

    2015-11-01

    To investigate the relationship between mode of first delivery and probability of subsequent childbearing. Population-based study. Nationwide study in Sweden. A cohort of 771 690 women who delivered their first singleton infant in Sweden between 1992 and 2010. Using Cox's proportional-hazards regression models, risks of subsequent childbearing were compared across four modes of delivery. Hazard ratios (HRs) were calculated, using 95% confidence intervals (95% CIs). Probability of having a second and third child; interpregnancy interval. Compared with women who had a spontaneous vaginal first delivery, women who delivered by vacuum extraction were less likely to have a second pregnancy (HR 0.96, 95% CI 0.95-0.97), and the probabilities of a second childbirth were substantially lower among women with a previous emergency caesarean section (HR 0.85, 95% CI 0.84-0.86) or an elective caesarean section (HR 0.82, 95% CI 0.80-0.83). There were no clinically important differences in the median time between first and second pregnancy by mode of first delivery. Compared with women younger than 30 years of age, older women were more negatively affected by a vacuum extraction with respect to the probability of having a second child. A primary vacuum extraction decreased the probability of having a third child by 4%, but having two consecutive vacuum extraction deliveries did not further alter the probability. A first delivery by vacuum extraction does not reduce the probability of subsequent childbearing to the same extent as a first delivery by emergency or elective caesarean section. © 2014 Royal College of Obstetricians and Gynaecologists.

  1. Quantum Behaved Particle Swarm Optimization Algorithm Based on Artificial Fish Swarm

    OpenAIRE

    Yumin, Dong; Li, Zhao

    2014-01-01

    Quantum behaved particle swarm algorithm is a new intelligent optimization algorithm; the algorithm has less parameters and is easily implemented. In view of the existing quantum behaved particle swarm optimization algorithm for the premature convergence problem, put forward a quantum particle swarm optimization algorithm based on artificial fish swarm. The new algorithm based on quantum behaved particle swarm algorithm, introducing the swarm and following activities, meanwhile using the a...

  2. Maternal smoking in pregnancy and risk for congenital malformations: results of a Danish register-based cohort study.

    Science.gov (United States)

    Leite, Mimmi; Albieri, Vanna; Kjaer, Susanne K; Jensen, Allan

    2014-08-01

    To examine the association between maternal smoking during pregnancy and risk for congenital malformations. Population-based prospective cohort study. Denmark. A total of 838 265 singleton liveborn babies delivered in Denmark between 1997 and 2010 and registered in the Danish Medical Birth Register containing detailed information on smoking during pregnancy and congenital malformations. Associations [odds ratios (OR) with 95% CI] between maternal smoking and risk for various groups of congenital malformations, investigated using the generalized estimating equation for binary outcomes, with adjustment for potential confounders. Groups of congenital malformations. Ever smoking during pregnancy did not increase the overall risk for congenital malformations, but increased risks were observed for multiple malformations (i.e. when two or more malformations are diagnosed in a child) (odds ratio 1.06, 95% confidence interval 1.01-1.10) and various main groups of congenital malformations including the cardiovascular system (odds ratio 1.13, 95% confidence interval 1.07-1.19), the respiratory system (odds ratio 1.25, 95% confidence interval 1.11-1.41), the digestive system (odds ratio 1.15, 95% confidence interval 1.07-1.24) and oral clefts (odds ratio 1.29, 95% confidence interval 1.14-1.46), as well as for some specific congenital malformations including cardiac septal defects, malformations of the pulmonary and tricuspid valves, malformations of the great arteries, pyloric stenosis and clubfoot. Infants of women who quit smoking during the first two trimesters had no increased risk for most groups of congenital malformations. Maternal smoking increases the risk for a number of congenital malformations. Future smoking cessation programs should focus on this adverse health aspect in order to encourage more women to quit smoking before or in early pregnancy. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

  3. An association between initiation of selective serotonin reuptake inhibitors and suicide - a nationwide register-based case-crossover study.

    Directory of Open Access Journals (Sweden)

    Charlotte Björkenstam

    Full Text Available BACKGROUND: Treatment with selective serotonin reuptake inhibitors (SSRI is one of the most common treatments for depression. It is however not clear whether or not there is an increased short-term suicide risk during initiation with SSRI. METHODS: A register-based nationwide case-crossover study including 5,866 suicides, 1,698 women and 4,168 men, from the Death Register 2007-2010 in Sweden. SSRI initiation was defined as a dispensed prescription of SSRI within 28 days prior to the date of suicide with no previous dispensed prescription of SSRI within 4 months prior that prescription. The control period took place one year earlier. Odds ratio (OR was estimated using conditional logistic regression. RESULT: During the 28 day period prior to suicide 48 women and 138 men were exposed to SSRI initiation (while not being exposed in the control period and 22 women and 43 men were exposed in the control period (while not being exposed in the case period. The OR for suicide after initiation with SSRI was 2.7 (95% CI: 1.6-44 for women, and 4.3 (95% CI: 3.0-6.1 for men. The highest OR was found 8-11 days after initiation with SSRI 9.7 (95% CI: 3.0-31.7 for women and men combined. CONCLUSION: The main limitation in this study is confounding by indication, but the descriptive question is however not confounded by indication. Together with plausible biological mechanisms and previous clinical and epidemiological observations our findings, linking initiation of SSRI to increased short-term suicide risk, deserve further attention specifically in the clinical setting.

  4. The recognition of female voice based on voice registers in singing techniques in real-time using hankel transform method and macdonald function

    Science.gov (United States)

    Meiyanti, R.; Subandi, A.; Fuqara, N.; Budiman, M. A.; Siahaan, A. P. U.

    2018-03-01

    A singer doesn’t just recite the lyrics of a song, but also with the use of particular sound techniques to make it more beautiful. In the singing technique, more female have a diverse sound registers than male. There are so many registers of the human voice, but the voice registers used while singing, among others, Chest Voice, Head Voice, Falsetto, and Vocal fry. Research of speech recognition based on the female’s voice registers in singing technique is built using Borland Delphi 7.0. Speech recognition process performed by the input recorded voice samples and also in real time. Voice input will result in weight energy values based on calculations using Hankel Transformation method and Macdonald Functions. The results showed that the accuracy of the system depends on the accuracy of sound engineering that trained and tested, and obtained an average percentage of the successful introduction of the voice registers record reached 48.75 percent, while the average percentage of the successful introduction of the voice registers in real time to reach 57 percent.

  5. No evidence of a causal relationship between hypothyroidism and glaucoma: A Danish nationwide register-based cohort study.

    Science.gov (United States)

    Thvilum, Marianne; Brandt, Frans; Brix, Thomas Heiberg; Hegedüs, Laszlo

    2018-01-01

    An interrelationship between hypothyroidism and glaucoma, due to a shared autoimmune background or based on deposition of mucopolysaccharides in the trabecular meshwork in the eye, has been suggested but is at present unsubstantiated. Therefore, our objective was to investigate, at a nationwide and population-based level, whether there is such an association. Observational cohort study using record-linkage data from nationwide Danish health registers. 121,799 individuals diagnosed with a first episode of hypothyroidism were identified and were matched with 4 non-hypothyroid controls according to age and sex. Prevalence of glaucoma was recorded and cases and controls were followed over a mean of 7.1 years (range 0-17). Logistic and Cox regression models were used to assess the risk of glaucoma before and after the diagnosis of hypothyroidism, respectively. Overall, we found a higher prevalence of glaucoma in subjects with hypothyroidism as compared to controls (4.6% vs. 4.3%, p glaucoma [1.09; 95% confidence interval (CI): 1.04-1.13]. Based on the Cox regression model, there was no increased risk of glaucoma after the diagnosis of hypothyroidism [hazard ratio (HR) 1.00; 95% CI: 0.96-1.06], and the HR decreased further after adjusting for pre-existing co-morbidity (0.88; 95% CI: 0.84-0.93). There was an increased risk of glaucoma before but not after the diagnosis of hypothyroidism, suggesting that screening for glaucoma in hypothyroid individuals is unwarranted.

  6. Unconditionally secure commitment in position-based quantum cryptography.

    Science.gov (United States)

    Nadeem, Muhammad

    2014-10-27

    A new commitment scheme based on position-verification and non-local quantum correlations is presented here for the first time in literature. The only credential for unconditional security is the position of committer and non-local correlations generated; neither receiver has any pre-shared data with the committer nor does receiver require trusted and authenticated quantum/classical channels between him and the committer. In the proposed scheme, receiver trusts the commitment only if the scheme itself verifies position of the committer and validates her commitment through non-local quantum correlations in a single round. The position-based commitment scheme bounds committer to reveal valid commitment within allocated time and guarantees that the receiver will not be able to get information about commitment unless committer reveals. The scheme works for the commitment of both bits and qubits and is equally secure against committer/receiver as well as against any third party who may have interests in destroying the commitment. Our proposed scheme is unconditionally secure in general and evades Mayers and Lo-Chau attacks in particular.

  7. Quantum Jarzynski equality of measurement-based work extraction.

    Science.gov (United States)

    Morikuni, Yohei; Tajima, Hiroyasu; Hatano, Naomichi

    2017-03-01

    Many studies of quantum-size heat engines assume that the dynamics of an internal system is unitary and that the extracted work is equal to the energy loss of the internal system. Both assumptions, however, should be under scrutiny. In the present paper, we analyze quantum-scale heat engines, employing the measurement-based formulation of the work extraction recently introduced by Hayashi and Tajima [M. Hayashi and H. Tajima, arXiv:1504.06150]. We first demonstrate the inappropriateness of the unitary time evolution of the internal system (namely, the first assumption above) using a simple two-level system; we show that the variance of the energy transferred to an external system diverges when the dynamics of the internal system is approximated to a unitary time evolution. Second, we derive the quantum Jarzynski equality based on the formulation of Hayashi and Tajima as a relation for the work measured by an external macroscopic apparatus. The right-hand side of the equality reduces to unity for "natural" cyclic processes but fluctuates wildly for noncyclic ones, exceeding unity often. This fluctuation should be detectable in experiments and provide evidence for the present formulation.

  8. Mini array of quantum Hall devices based on epitaxial graphene

    International Nuclear Information System (INIS)

    Novikov, S.; Lebedeva, N.; Hämäläinen, J.; Iisakka, I.; Immonen, P.; Manninen, A. J.; Satrapinski, A.

    2016-01-01

    Series connection of four quantum Hall effect (QHE) devices based on epitaxial graphene films was studied for realization of a quantum resistance standard with an up-scaled value. The tested devices showed quantum Hall plateaux R H,2 at a filling factor v = 2 starting from a relatively low magnetic field (between 4 T and 5 T) when the temperature was 1.5 K. The precision measurements of quantized Hall resistance of four QHE devices connected by triple series connections and external bonding wires were done at B = 7 T and T = 1.5 K using a commercial precision resistance bridge with 50 μA current through the QHE device. The results showed that the deviation of the quantized Hall resistance of the series connection of four graphene-based QHE devices from the expected value of 4×R H,2  = 2 h/e 2 was smaller than the relative standard uncertainty of the measurement (<1 × 10 −7 ) limited by the used resistance bridge.

  9. Threshold quantum secret sharing based on single qubit

    Science.gov (United States)

    Lu, Changbin; Miao, Fuyou; Meng, Keju; Yu, Yue

    2018-03-01

    Based on unitary phase shift operation on single qubit in association with Shamir's ( t, n) secret sharing, a ( t, n) threshold quantum secret sharing scheme (or ( t, n)-QSS) is proposed to share both classical information and quantum states. The scheme uses decoy photons to prevent eavesdropping and employs the secret in Shamir's scheme as the private value to guarantee the correctness of secret reconstruction. Analyses show it is resistant to typical intercept-and-resend attack, entangle-and-measure attack and participant attacks such as entanglement swapping attack. Moreover, it is easier to realize in physic and more practical in applications when compared with related ones. By the method in our scheme, new ( t, n)-QSS schemes can be easily constructed using other classical ( t, n) secret sharing.

  10. Quantum engineering of transistors based on 2D materials heterostructures

    Science.gov (United States)

    Iannaccone, Giuseppe; Bonaccorso, Francesco; Colombo, Luigi; Fiori, Gianluca

    2018-03-01

    Quantum engineering entails atom-by-atom design and fabrication of electronic devices. This innovative technology that unifies materials science and device engineering has been fostered by the recent progress in the fabrication of vertical and lateral heterostructures of two-dimensional materials and by the assessment of the technology potential via computational nanotechnology. But how close are we to the possibility of the practical realization of next-generation atomically thin transistors? In this Perspective, we analyse the outlook and the challenges of quantum-engineered transistors using heterostructures of two-dimensional materials against the benchmark of silicon technology and its foreseeable evolution in terms of potential performance and manufacturability. Transistors based on lateral heterostructures emerge as the most promising option from a performance point of view, even if heterostructure formation and control are in the initial technology development stage.

  11. A Novel Quantum Image Steganography Scheme Based on LSB

    Science.gov (United States)

    Zhou, Ri-Gui; Luo, Jia; Liu, XingAo; Zhu, Changming; Wei, Lai; Zhang, Xiafen

    2018-06-01

    Based on the NEQR representation of quantum images and least significant bit (LSB) scheme, a novel quantum image steganography scheme is proposed. The sizes of the cover image and the original information image are assumed to be 4 n × 4 n and n × n, respectively. Firstly, the bit-plane scrambling method is used to scramble the original information image. Then the scrambled information image is expanded to the same size of the cover image by using the key only known to the operator. The expanded image is scrambled to be a meaningless image with the Arnold scrambling. The embedding procedure and extracting procedure are carried out by K 1 and K 2 which are under control of the operator. For validation of the presented scheme, the peak-signal-to-noise ratio (PSNR), the capacity, the security of the images and the circuit complexity are analyzed.

  12. A quantum heat engine based on Tavis-Cummings model

    Science.gov (United States)

    Sun, Kai-Wei; Li, Ran; Zhang, Guo-Feng

    2017-09-01

    This paper will investigate a four-stroke quantum heat engine based on the Tavis-Cummings model. The cycle of the heat engine is similar to the Otto cycle in classical thermodynamics. The relationship between output power as well as cycle efficiency and external physical system parameters are given. Under this condition, the entanglement behavior of the system will be studied. The system can show considerable entanglement by strictly controlling relevant parameters. Unlike common two-level quantum heat engines, efficiency is a function of temperature, showing interesting and unexpected phenomena. Several ways to adjust engine properties by external parameters are proposed, with which the output power and efficiency can be optimized. The heat engine model exhibits high efficiency and output power with the participation of a small number of photons, and decay rapidly as the number of photons increases in entangled area but shows interesting behaviors in non-entangled area of photon numbers.

  13. Position-based quantum cryptography over untrusted networks

    International Nuclear Information System (INIS)

    Nadeem, Muhammad

    2014-01-01

    In this article, we propose quantum position verification (QPV) schemes where all the channels are untrusted except the position of the prover and distant reference stations of verifiers. We review and analyze the existing QPV schemes containing some pre-shared data between the prover and verifiers. Most of these schemes are based on non-cryptographic assumptions, i.e. quantum/classical channels between the verifiers are secure. It seems impractical in an environment fully controlled by adversaries and would lead to security compromise in practical implementations. However, our proposed formula for QPV is more robust, secure and according to the standard assumptions of cryptography. Furthermore, once the position of the prover is verified, our schemes establish secret keys in parallel and can be used for authentication and secret communication between the prover and verifiers. (paper)

  14. Partition-based discrete-time quantum walks

    Science.gov (United States)

    Konno, Norio; Portugal, Renato; Sato, Iwao; Segawa, Etsuo

    2018-04-01

    We introduce a family of discrete-time quantum walks, called two-partition model, based on two equivalence-class partitions of the computational basis, which establish the notion of local dynamics. This family encompasses most versions of unitary discrete-time quantum walks driven by two local operators studied in literature, such as the coined model, Szegedy's model, and the 2-tessellable staggered model. We also analyze the connection of those models with the two-step coined model, which is driven by the square of the evolution operator of the standard discrete-time coined walk. We prove formally that the two-step coined model, an extension of Szegedy model for multigraphs, and the two-tessellable staggered model are unitarily equivalent. Then, selecting one specific model among those families is a matter of taste not generality.

  15. Quantum engineering of transistors based on 2D materials heterostructures.

    Science.gov (United States)

    Iannaccone, Giuseppe; Bonaccorso, Francesco; Colombo, Luigi; Fiori, Gianluca

    2018-03-01

    Quantum engineering entails atom-by-atom design and fabrication of electronic devices. This innovative technology that unifies materials science and device engineering has been fostered by the recent progress in the fabrication of vertical and lateral heterostructures of two-dimensional materials and by the assessment of the technology potential via computational nanotechnology. But how close are we to the possibility of the practical realization of next-generation atomically thin transistors? In this Perspective, we analyse the outlook and the challenges of quantum-engineered transistors using heterostructures of two-dimensional materials against the benchmark of silicon technology and its foreseeable evolution in terms of potential performance and manufacturability. Transistors based on lateral heterostructures emerge as the most promising option from a performance point of view, even if heterostructure formation and control are in the initial technology development stage.

  16. Block-free optical quantum Banyan network based on quantum state fusion and fission

    International Nuclear Information System (INIS)

    Zhu Chang-Hua; Meng Yan-Hong; Quan Dong-Xiao; Zhao Nan; Pei Chang-Xing

    2014-01-01

    Optical switch fabric plays an important role in building multiple-user optical quantum communication networks. Owing to its self-routing property and low complexity, a banyan network is widely used for building switch fabric. While, there is no efficient way to remove internal blocking in a banyan network in a classical way, quantum state fusion, by which the two-dimensional internal quantum states of two photons could be combined into a four-dimensional internal state of a single photon, makes it possible to solve this problem. In this paper, we convert the output mode of quantum state fusion from spatial-polarization mode into time-polarization mode. By combining modified quantum state fusion and quantum state fission with quantum Fredkin gate, we propose a practical scheme to build an optical quantum switch unit which is block free. The scheme can be extended to building more complex units, four of which are shown in this paper. (general)

  17. Universal quantum gates for Single Cooper Pair Box based quantum computing

    Science.gov (United States)

    Echternach, P.; Williams, C. P.; Dultz, S. C.; Braunstein, S.; Dowling, J. P.

    2000-01-01

    We describe a method for achieving arbitrary 1-qubit gates and controlled-NOT gates within the context of the Single Cooper Pair Box (SCB) approach to quantum computing. Such gates are sufficient to support universal quantum computation.

  18. Case mix adjustment of health outcomes, resource use and process indicators in childbirth care: a register-based study.

    Science.gov (United States)

    Mesterton, Johan; Lindgren, Peter; Ekenberg Abreu, Anna; Ladfors, Lars; Lilja, Monica; Saltvedt, Sissel; Amer-Wåhlin, Isis

    2016-05-31

    Unwarranted variation in care practice and outcomes has gained attention and inter-hospital comparisons are increasingly being used to highlight and understand differences between hospitals. Adjustment for case mix is a prerequisite for meaningful comparisons between hospitals with different patient populations. The objective of this study was to identify and quantify maternal characteristics that impact a set of important indicators of health outcomes, resource use and care process and which could be used for case mix adjustment of comparisons between hospitals. In this register-based study, 139 756 deliveries in 2011 and 2012 were identified in regional administrative systems from seven Swedish regions, which together cover 67 % of all deliveries in Sweden. Data were linked to the Medical birth register and Statistics Sweden's population data. A number of important indicators in childbirth care were studied: Caesarean section (CS), induction of labour, length of stay, perineal tears, haemorrhage > 1000 ml and post-partum infections. Sociodemographic and clinical characteristics deemed relevant for case mix adjustment of outcomes and resource use were identified based on previous literature and based on clinical expertise. Adjustment using logistic and ordinary least squares regression analysis was performed to quantify the impact of these characteristics on the studied indicators. Almost all case mix factors analysed had an impact on CS rate, induction rate and length of stay and the effect was highly statistically significant for most factors. Maternal age, parity, fetal presentation and multiple birth were strong predictors of all these indicators but a number of additional factors such as born outside the EU, body mass index (BMI) and several complications during pregnancy were also important risk factors. A number of maternal characteristics had a noticeable impact on risk of perineal tears, while the impact of case mix factors was less pronounced for

  19. Simple security proof of quantum key distribution based on complementarity

    International Nuclear Information System (INIS)

    Koashi, M

    2009-01-01

    We present an approach to the unconditional security of quantum key distribution protocols based on a complementarity argument. The approach is applicable to, but not limited to, every case that has been treated via the argument by Shor and Preskill based on entanglement distillation, with a benefit of decoupling of the error correction from the privacy amplification. It can also treat cases with uncharacterized apparatuses. We derive a secure key rate for the Bennett-Brassard-1984 protocol with an arbitrary source characterized only by a single parameter representing the basis dependence.

  20. Minimal ancilla mediated quantum computation

    International Nuclear Information System (INIS)

    Proctor, Timothy J.; Kendon, Viv

    2014-01-01

    Schemes of universal quantum computation in which the interactions between the computational elements, in a computational register, are mediated by some ancillary system are of interest due to their relevance to the physical implementation of a quantum computer. Furthermore, reducing the level of control required over both the ancillary and register systems has the potential to simplify any experimental implementation. In this paper we consider how to minimise the control needed to implement universal quantum computation in an ancilla-mediated fashion. Considering computational schemes which require no measurements and hence evolve by unitary dynamics for the global system, we show that when employing an ancilla qubit there are certain fixed-time ancilla-register interactions which, along with ancilla initialisation in the computational basis, are universal for quantum computation with no additional control of either the ancilla or the register. We develop two distinct models based on locally inequivalent interactions and we then discuss the relationship between these unitary models and the measurement-based ancilla-mediated models known as ancilla-driven quantum computation. (orig.)

  1. Reproduction and mode of delivery in women with vaginismus or localised provoked vestibulodynia: a Swedish register-based study.

    Science.gov (United States)

    Möller, L; Josefsson, A; Bladh, M; Lilliecreutz, C; Sydsjö, G

    2015-02-01

    To compare sociodemographics, parity and mode of delivery between women diagnosed with vaginismus or localised provoked vestibulodynia (LPV) to women without a diagnosis before first pregnancy. Retrospective, population-based register study. Sweden. All women born in Sweden 1973-83 who gave birth for the first time or remained nulliparous during the years 2001-09. Nationally linked registries were used to identify the study population. Women diagnosed with vaginismus or LPV were compared to all other women. Odds ratios for parity and mode of delivery were calculated using multinominal regression analysis and logistic regression. Parity and mode of delivery. Women with vaginismus/LPV were more likely to be unmarried (P = 0.001), unemployed (P = 0.012), have a higher educational level (P vaginismus/LPV more often delivered by caesarean section (P vaginismus/LPV were more likely to suffer a perineal laceration (adjusted OR 1.87, 95% CI 1.56-2.25). Women with vaginismus/LPV are less likely to give birth and those that do are more likely to deliver by caesarean section and have a caesarean section based upon maternal request. Those women delivering vaginally are more likely to suffer perineal laceration. These findings point to the importance of not only addressing sexual function in women with vaginismus/LPV but reproductive function as well. © 2014 Royal College of Obstetricians and Gynaecologists.

  2. Entropy in quantum information theory - Communication and cryptography

    DEFF Research Database (Denmark)

    Majenz, Christian

    in quantum Shannon theory. While immensely more entanglement-consuming, the variant of port based teleportation is interesting for applications like instantaneous non-local computation and attacks on quantum position-based cryptography. Port based teleportation cannot be implemented perfectly......, for vanishing error. As a byproduct, a new lower bound for the size of the program register for an approximate universal programmable quantum processor is derived. Finally, the mix is completed with a result in quantum cryptography. While quantum key distribution is the most well-known quantum cryptographic...... protocol, there has been increased interest in extending the framework of symmetric key cryptography to quantum messages. We give a new denition for information-theoretic quantum non-malleability, strengthening the previous denition by Ambainis et al. We show that quantum non-malleability implies secrecy...

  3. Research on Palmprint Identification Method Based on Quantum Algorithms

    Directory of Open Access Journals (Sweden)

    Hui Li

    2014-01-01

    Full Text Available Quantum image recognition is a technology by using quantum algorithm to process the image information. It can obtain better effect than classical algorithm. In this paper, four different quantum algorithms are used in the three stages of palmprint recognition. First, quantum adaptive median filtering algorithm is presented in palmprint filtering processing. Quantum filtering algorithm can get a better filtering result than classical algorithm through the comparison. Next, quantum Fourier transform (QFT is used to extract pattern features by only one operation due to quantum parallelism. The proposed algorithm exhibits an exponential speed-up compared with discrete Fourier transform in the feature extraction. Finally, quantum set operations and Grover algorithm are used in palmprint matching. According to the experimental results, quantum algorithm only needs to apply square of N operations to find out the target palmprint, but the traditional method needs N times of calculation. At the same time, the matching accuracy of quantum algorithm is almost 100%.

  4. Quantum Models of Classical World

    Directory of Open Access Journals (Sweden)

    Petr Hájíček

    2013-02-01

    Full Text Available This paper is a review of our recent work on three notorious problems of non-relativistic quantum mechanics: realist interpretation, quantum theory of classical properties, and the problem of quantum measurement. A considerable progress has been achieved, based on four distinct new ideas. First, objective properties are associated with states rather than with values of observables. Second, all classical properties are selected properties of certain high entropy quantum states of macroscopic systems. Third, registration of a quantum system is strongly disturbed by systems of the same type in the environment. Fourth, detectors must be distinguished from ancillas and the states of registered systems are partially dissipated and lost in the detectors. The paper has two aims: a clear explanation of all new results and a coherent and contradiction-free account of the whole quantum mechanics including all necessary changes of its current textbook version.

  5. Quantum Dialogue with Authentication Based on Bell States

    Science.gov (United States)

    Shen, Dongsu; Ma, Wenping; Yin, Xunru; Li, Xiaoping

    2013-06-01

    We propose an authenticated quantum dialogue protocol, which is based on a shared private quantum entangled channel. In this protocol, the EPR pairs are randomly prepared in one of the four Bell states for communication. By performing four Pauli operations on the shared EPR pairs to encode their shared authentication key and secret message, two legitimate users can implement mutual identity authentication and quantum dialogue without the help from the third party authenticator. Furthermore, due to the EPR pairs which are used for secure communication are utilized to implement authentication and the whole authentication process is included in the direct secure communication process, it does not require additional particles to realize authentication in this protocol. The updated authentication key provides the counterparts with a new authentication key for the next authentication and direct communication. Compared with other secure communication with authentication protocols, this one is more secure and efficient owing to the combination of authentication and direct communication. Security analysis shows that it is secure against the eavesdropping attack, the impersonation attack and the man-in-the-middle (MITM) attack.

  6. Thermoelectric properties of an interacting quantum dot based heat engine

    Science.gov (United States)

    Erdman, Paolo Andrea; Mazza, Francesco; Bosisio, Riccardo; Benenti, Giuliano; Fazio, Rosario; Taddei, Fabio

    2017-06-01

    We study the thermoelectric properties and heat-to-work conversion performance of an interacting, multilevel quantum dot (QD) weakly coupled to electronic reservoirs. We focus on the sequential tunneling regime. The dynamics of the charge in the QD is studied by means of master equations for the probabilities of occupation. From here we compute the charge and heat currents in the linear response regime. Assuming a generic multiterminal setup, and for low temperatures (quantum limit), we obtain analytical expressions for the transport coefficients which account for the interplay between interactions (charging energy) and level quantization. In the case of systems with two and three terminals we derive formulas for the power factor Q and the figure of merit Z T for a QD-based heat engine, identifying optimal working conditions which maximize output power and efficiency of heat-to-work conversion. Beyond the linear response we concentrate on the two-terminal setup. We first study the thermoelectric nonlinear coefficients assessing the consequences of large temperature and voltage biases, focusing on the breakdown of the Onsager reciprocal relation between thermopower and Peltier coefficient. We then investigate the conditions which optimize the performance of a heat engine, finding that in the quantum limit output power and efficiency at maximum power can almost be simultaneously maximized by choosing appropriate values of electrochemical potential and bias voltage. At last we study how energy level degeneracy can increase the output power.

  7. Solid-state nuclear-spin quantum computer based on magnetic resonance force microscopy

    International Nuclear Information System (INIS)

    Berman, G. P.; Doolen, G. D.; Hammel, P. C.; Tsifrinovich, V. I.

    2000-01-01

    We propose a nuclear-spin quantum computer based on magnetic resonance force microscopy (MRFM). It is shown that an MRFM single-electron spin measurement provides three essential requirements for quantum computation in solids: (a) preparation of the ground state, (b) one- and two-qubit quantum logic gates, and (c) a measurement of the final state. The proposed quantum computer can operate at temperatures up to 1 K. (c) 2000 The American Physical Society

  8. Threshold quantum state sharing based on entanglement swapping

    Science.gov (United States)

    Qin, Huawang; Tso, Raylin

    2018-06-01

    A threshold quantum state sharing scheme is proposed. The dealer uses the quantum-controlled-not operations to expand the d-dimensional quantum state and then uses the entanglement swapping to distribute the state to a random subset of participants. The participants use the single-particle measurements and unitary operations to recover the initial quantum state. In our scheme, the dealer can share different quantum states among different subsets of participants simultaneously. So the scheme will be very flexible in practice.

  9. Genetic algorithm based on qubits and quantum gates

    International Nuclear Information System (INIS)

    Silva, Joao Batista Rosa; Ramos, Rubens Viana

    2003-01-01

    Full text: Genetic algorithm, a computational technique based on the evolution of the species, in which a possible solution of the problem is coded in a binary string, called chromosome, has been used successfully in several kinds of problems, where the search of a minimal or a maximal value is necessary, even when local minima are present. A natural generalization of a binary string is a qubit string. Hence, it is possible to use the structure of a genetic algorithm having a sequence of qubits as a chromosome and using quantum operations in the reproduction in order to find the best solution in some problems of quantum information. For example, given a unitary matrix U what is the pair of qubits that, when applied at the input, provides the output state with maximal entanglement? In order to solve this problem, a population of chromosomes of two qubits was created. The crossover was performed applying the quantum gates CNOT and SWAP at the pair of qubits, while the mutation was performed applying the quantum gates Hadamard, Z and Not in a single qubit. The result was compared with a classical genetic algorithm used to solve the same problem. A hundred simulations using the same U matrix was performed. Both algorithms, hereafter named by CGA (classical) and QGA (using qu bits), reached good results close to 1 however, the number of generations needed to find the best result was lower for the QGA. Another problem where the QGA can be useful is in the calculation of the relative entropy of entanglement. We have tested our algorithm using 100 pure states chosen randomly. The stop criterion used was the error lower than 0.01. The main advantages of QGA are its good precision, robustness and very easy implementation. The main disadvantage is its low velocity, as happen for all kind of genetic algorithms. (author)

  10. Simulation of n-qubit quantum systems. III. Quantum operations

    Science.gov (United States)

    Radtke, T.; Fritzsche, S.

    2007-05-01

    During the last decade, several quantum information protocols, such as quantum key distribution, teleportation or quantum computation, have attracted a lot of interest. Despite the recent success and research efforts in quantum information processing, however, we are just at the beginning of understanding the role of entanglement and the behavior of quantum systems in noisy environments, i.e. for nonideal implementations. Therefore, in order to facilitate the investigation of entanglement and decoherence in n-qubit quantum registers, here we present a revised version of the FEYNMAN program for working with quantum operations and their associated (Jamiołkowski) dual states. Based on the implementation of several popular decoherence models, we provide tools especially for the quantitative analysis of quantum operations. Apart from the implementation of different noise models, the current program extension may help investigate the fragility of many quantum states, one of the main obstacles in realizing quantum information protocols today. Program summaryTitle of program: Feynman Catalogue identifier: ADWE_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWE_v3_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions: None Operating systems: Any system that supports MAPLE; tested under Microsoft Windows XP, SuSe Linux 10 Program language used:MAPLE 10 Typical time and memory requirements: Most commands that act upon quantum registers with five or less qubits take ⩽10 seconds of processor time (on a Pentium 4 processor with ⩾2 GHz or equivalent) and 5-20 MB of memory. Especially when working with symbolic expressions, however, the memory and time requirements critically depend on the number of qubits in the quantum registers, owing to the exponential dimension growth of the associated Hilbert space. For example, complex (symbolic) noise models (with several Kraus operators) for multi-qubit systems

  11. A Composed Protocol of Quantum Identity Authentication Plus Quantum Key Distribution Based on Squeezed States

    International Nuclear Information System (INIS)

    Zhang Sheng; Wang Jian; Tang Chaojing; Zhang Quan

    2011-01-01

    It is established that a single quantum cryptography protocol usually cooperates with other cryptographic systems, such as an authentication system, in the real world. However, few protocols have been proposed on how to combine two or more quantum protocols. To fill this gap, we propose a composed quantum protocol, containing both quantum identity authentication and quantum key distribution, using squeezed states. Hence, not only the identity can be verified, but also a new private key can be generated by our new protocol. We also analyze the security under an optimal attack, and the efficiency, which is defined by the threshold of the tolerant error rate, using Gaussian error function. (general)

  12. Spin-based all-optical quantum computation with quantum dots: Understanding and suppressing decoherence

    International Nuclear Information System (INIS)

    Calarco, T.; Datta, A.; Fedichev, P.; Zoller, P.; Pazy, E.

    2003-01-01

    We present an all-optical implementation of quantum computation using semiconductor quantum dots. Quantum memory is represented by the spin of an excess electron stored in each dot. Two-qubit gates are realized by switching on trion-trion interactions between different dots. State selectivity is achieved via conditional laser excitation exploiting Pauli exclusion principle. Read out is performed via a quantum-jump technique. We analyze the effect on our scheme's performance of the main imperfections present in real quantum dots: exciton decay, hole mixing, and phonon decoherence. We introduce an adiabatic gate procedure that allows one to circumvent these effects and evaluate quantitatively its fidelity

  13. Quantum control mechanism analysis through field based Hamiltonian encoding

    International Nuclear Information System (INIS)

    Mitra, Abhra; Rabitz, Herschel

    2006-01-01

    Optimal control of quantum dynamics in the laboratory is proving to be increasingly successful. The control fields can be complex, and the mechanisms by which they operate have often remained obscure. Hamiltonian encoding (HE) has been proposed as a method for understanding mechanisms in quantum dynamics. In this context mechanism is defined in terms of the dominant quantum pathways leading to the final state of the controlled system. HE operates by encoding a special modulation into the Hamiltonian and decoding its signature in the dynamics to determine the dominant pathway amplitudes. Earlier work encoded the modulation directly into the Hamiltonian operators. This present work introduces the alternative scheme of field based HE, where the modulation is encoded into the control field and not directly into the Hamiltonian operators. This distinct form of modulation yields a new perspective on mechanism and is computationally faster than the earlier approach. Field based encoding is also an important step towards a laboratory based algorithm for HE as it is the only form of encoding that may be experimentally executed. HE is also extended to cover systems with noise and uncertainty and finally, a hierarchical algorithm is introduced to reveal mechanism in a stepwise fashion of ever increasing detail as desired. This new hierarchical algorithm is an improvement over earlier approaches to HE where the entire mechanism was determined in one stroke. The improvement comes from the use of less complex modulation schemes, which leads to fewer evaluations of Schroedinger's equation. A number of simulations are presented on simple systems to illustrate the new field based encoding technique for mechanism assessment

  14. Web-Based versus High-Fidelity Simulation Training for Certified Registered Nurse Anesthetists in the Management of High Risk/Low Occurrence Anesthesia Events

    Science.gov (United States)

    Kimemia, Judy

    2017-01-01

    Purpose: The purpose of this project was to compare web-based to high-fidelity simulation training in the management of high risk/low occurrence anesthesia related events, to enhance knowledge acquisition for Certified Registered Nurse Anesthetists (CRNAs). This project was designed to answer the question: Is web-based training as effective as…

  15. Bandgap Engineering of 1300 nm Quantum Dots/Quantum Well Nanostructures Based Devices

    KAUST Repository

    Alhashim, Hala H.

    2016-05-29

    The main objectives of this thesis are to develop viable process and/or device technologies for bandgap tuning of 1300-nm InGaAs/GaAs quantum-dot (QD) laser structures, and broad linewidth 1300-nm InGaAsP/InP quantum well (QW) superluminescent diode structures. The high performance bandgap-engineered QD laser structures were achieved by employing quantum-dot intermixing (QDI) based on impurity free vacancy diffusion (IFVD) technique for eventual seamless active-passive integration, and bandgap-tuned lasers. QDI using various dielectric-capping materials, such as HfO2, SrTiO3, TiO2, Al2O3 and ZnO, etc, were experimented in which the resultant emission wavelength can be blueshifted to ∼ 1100 nm ─ 1200 nm range depending on process conditions. The significant results extracted from the PL characterization were used to perform an extensive laser characterization. The InAs/GaAs quantum-dot lasers with QDs transition energies were blueshifted by ~185 nm, and lasing around ~1070 – 1190 nm was achieved. Furthermore, from the spectral analysis, a simultaneous five-state lasing in the InAs/InGaAs intermixed QD laser was experimentally demonstrated for the first time in the very important wavelength range from 1030 to 1125 nm. The QDI methodology enabled the facile formation of a plethora of devices with various emission wavelengths suitable for a wide range of applications in the infrared. In addition, the wavelength range achieved is also applicable for coherent light generation in the green – yellow – orange visible wavelength band via frequency doubling, which is a cost-effective way of producing compact devices for pico-projectors, semiconductor laser based solid state lighting, etc. [1, 2] In QW-based superluminescent diode, the problem statement lies on achieving a flat-top and ultra-wide emission bandwidth. The approach was to design an inhomogeneous active region with a comparable simultaneous emission from different transition states in the QW stacks, in

  16. A Novel Quantum Solution to Privacy-Preserving Nearest Neighbor Query in Location-Based Services

    Science.gov (United States)

    Luo, Zhen-yu; Shi, Run-hua; Xu, Min; Zhang, Shun

    2018-04-01

    We present a cheating-sensitive quantum protocol for Privacy-Preserving Nearest Neighbor Query based on Oblivious Quantum Key Distribution and Quantum Encryption. Compared with the classical related protocols, our proposed protocol has higher security, because the security of our protocol is based on basic physical principles of quantum mechanics, instead of difficulty assumptions. Especially, our protocol takes single photons as quantum resources and only needs to perform single-photon projective measurement. Therefore, it is feasible to implement this protocol with the present technologies.

  17. Differential utilization of primary health care services among older immigrants and Norwegians: a register-based comparative study in Norway.

    Science.gov (United States)

    Diaz, Esperanza; Kumar, Bernadette N

    2014-11-26

    Aging in an unfamiliar landscape can pose health challenges for the growing numbers of immigrants and their health care providers. Therefore, better understanding of how different immigrant groups use Primary Health Care (PHC), and the underlying factors that explain utilization is needed to provide adequate and appropriate public health responses. Our aim is to describe and compare the use of PHC between elderly immigrants and Norwegians. Registry-based study using merged data from the National Population Register and the Norwegian Health Economics Administration database. All 50 year old or older Norwegians with both parents from Norway (1,516,012) and immigrants with both parents from abroad (89,861) registered in Norway in 2008 were included. Descriptive analyses were carried out. Immigrants were categorised according to country of origin, reason for migration and length of stay in Norway. Binary logistic regression analyses were conducted to study the utilization of PHC comparing Norwegians and immigrants, and to assess associations between utilization and both length of stay and reason for immigration, adjusting for other socioeconomic variables. A higher proportion of Norwegians used PHC services compared to immigrants. While immigrants from high-income countries used PHC less than Norwegians disregarding age (OR from 0.65 to 0.92 depending on age group), they had similar number of diagnoses when in contact with PHC. Among immigrants from other countries, however, those 50 to 65 years old used PHC services more often (OR 1.22) than Norwegians and had higher comorbidity levels, but this pattern was reversed for older adults (OR 0.56 to 0.47 for 66-80 and 80+ years respectively). For all immigrants, utilization of PHC increased with longer stay in Norway and was higher for refugees (1.67 to 1.90) but lower for labour immigrants (0.33 to 0.45) compared to immigrants for family reunification. However, adjustment for education and income levels reduced most

  18. Levelling-out and register variation in the translations of experienced and inexperienced translators: a corpus-based study

    Directory of Open Access Journals (Sweden)

    Karien Redelinghuys

    2016-07-01

    Full Text Available Explicitation, simplification, normalisation and levelling-out, the four features of translation proposed by Baker (1996, have attracted considerable attention in translation studies. Although the first three have been studied extensively, levelling-out has been the subject of less empirical investigation. Furthermore, there are no studies to date that have investigated the extent to which levelling-out occurs in translations by experienced translators and inexperienced translators. In this study, levelling-out is operationalised in terms of register. It is hypothesised that less register variation will be apparent in translations by inexperienced translators and, in keeping with the features of translation hypothesis, it is predicted that select linguistic features will demonstrate less register variation in translations than in non-translations. A custom-built corpus was compiled to test these hypotheses. While some light is shed on how translation expertise contributes to register sensitivity and the distribution of certain features across different registers, little evidence could be found for levelling-out as register variation is evident in the translation corpora.

  19. Real-time co-registered ultrasound and photoacoustic imaging system based on FPGA and DSP architecture

    Science.gov (United States)

    Alqasemi, Umar; Li, Hai; Aguirre, Andres; Zhu, Quing

    2011-03-01

    Co-registering ultrasound (US) and photoacoustic (PA) imaging is a logical extension to conventional ultrasound because both modalities provide complementary information of tumor morphology, tumor vasculature and hypoxia for cancer detection and characterization. In addition, both modalities are capable of providing real-time images for clinical applications. In this paper, a Field Programmable Gate Array (FPGA) and Digital Signal Processor (DSP) module-based real-time US/PA imaging system is presented. The system provides real-time US/PA data acquisition and image display for up to 5 fps* using the currently implemented DSP board. It can be upgraded to 15 fps, which is the maximum pulse repetition rate of the used laser, by implementing an advanced DSP module. Additionally, the photoacoustic RF data for each frame is saved for further off-line processing. The system frontend consists of eight 16-channel modules made of commercial and customized circuits. Each 16-channel module consists of two commercial 8-channel receiving circuitry boards and one FPGA board from Analog Devices. Each receiving board contains an IC† that combines. 8-channel low-noise amplifiers, variable-gain amplifiers, anti-aliasing filters, and ADC's‡ in a single chip with sampling frequency of 40MHz. The FPGA board captures the LVDSξ Double Data Rate (DDR) digital output of the receiving board and performs data conditioning and subbeamforming. A customized 16-channel transmission circuitry is connected to the two receiving boards for US pulseecho (PE) mode data acquisition. A DSP module uses External Memory Interface (EMIF) to interface with the eight 16-channel modules through a customized adaptor board. The DSP transfers either sub-beamformed data (US pulse-echo mode or PAI imaging mode) or raw data from FPGA boards to its DDR-2 memory through the EMIF link, then it performs additional processing, after that, it transfer the data to the PC** for further image processing. The PC code

  20. Early childhood adversities and risk of eating disorders in women: A Danish register-based cohort study.

    Science.gov (United States)

    Larsen, Janne Tidselbak; Munk-Olsen, Trine; Bulik, Cynthia M; Thornton, Laura M; Koch, Susanne Vinkel; Mortensen, Preben Bo; Petersen, Liselotte

    2017-12-01

    Previous studies evaluating the association between early childhood adversities and eating disorders have yielded conflicting results. The aim of this study is to examine the association between a range of adversities and risk of anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS) in 495,244 women. In this nationwide, register-based cohort study, nine types of early childhood adversity (family disruption, residential instability, placement in out-of-home care, familial death, parental somatic illness, parental psychiatric illness, parental disability, severe parental criminality, and parental substance use disorder) were defined and exposure during the first 6 years of life was determined. Hazard ratios for eating disorders were calculated using Cox regression. Few adversities were significantly associated with AN, and for each, the presence of the adversity was associated with lower risk for AN. BN, and EDNOS were positively associated with several types of adversities. AN rates were unchanged or reduced by up to 54% by adversities, whereas rates of BN and EDNOS were unchanged or increased by adversities by up to 49 and 89%, respectively. Our findings indicate that childhood adversities appear to be associated with an increased risk of BN and in particular EDNOS, whereas they seem to be either unassociated or associated with a decreased risk of AN. © 2017 Wiley Periodicals, Inc.

  1. Hand eczema in hairdressers: a Danish register-based study of the prevalence of hand eczema and its career consequences.

    Science.gov (United States)

    Lysdal, Susan Hovmand; Søsted, Heidi; Andersen, Klaus Ejner; Johansen, Jeanne Duus

    2011-09-01

    Occupational hand eczema is common in hairdressers, owing to wet work and hairdressing chemicals. To estimate the prevalence of hand eczema and its career consequences among hairdressers in Denmark. A register-based study was conducted, comprising all graduates from hairdressing vocational schools from 1985 to 2007 (n = 7840). The participants received a self-administered postal questionnaire including questions on hand eczema, atopic dermatitis, and career change. A response rate of 67.9% (n = 5324) was obtained. Of the respondents, 44.3% no longer worked as hairdressers and had worked for an average of 8.4 years in the profession before leaving it. Hand eczema was more common among ex-hairdressers (48.4%) than among current hairdressers (37.6%) (p reason for career change. In this group, logistic regression analysis showed that chronic hand eczema contributed the most to the decision to change career (odds ratio 50.12; 95% confidence interval 18.3-137). Hairdressers work an average of 8.4 years in the profession before leaving it, and hand eczema contributes significantly to this career change. © 2011 John Wiley & Sons A/S.

  2. Positive predictive value of a register-based algorithm using the Danish National Registries to identify suicidal events

    DEFF Research Database (Denmark)

    Gasse, Christiane; Danielsen, Andreas Aalkjaer; Pedersen, Marianne Giørtz

    2018-01-01

    events overall, by gender, age groups, and calendar time. RESULTS: We retrieved medical records for 357 (75%) people. The PPV of the DK-algorithm to identify suicidal events was 51.5% (95% CI: 46.4-56.7) overall, 42.7% (95% CI: 35.2-50.5) in males, and 58.5% (95% CI: 51.6-65.1) in females. The PPV varied...... further across age groups and calendar time. After excluding cases identified via the DK-algorithm by unspecific codes of intoxications and injury, the PPV improved slightly (56.8% [95% CI: 50.0-63.4]). CONCLUSIONS: The DK-algorithm can reliably identify self-harm with suicidal intention in 52......PURPOSE: It is not possible to fully assess intention of self-harm and suicidal events using information from administrative databases. We conducted a validation study of intention of suicide attempts/self-harm contacts identified by a commonly applied Danish register-based algorithm (DK...

  3. Modelling software failures of digital I and C in probabilistic safety analyses based on the TELEPERM registered XS operating experience

    International Nuclear Information System (INIS)

    Jockenhoevel-Barttfeld, Mariana; Taurines Andre; Baeckstroem, Ola; Holmberg, Jan-Erik; Porthin, Markus; Tyrvaeinen, Tero

    2015-01-01

    Digital instrumentation and control (I and C) systems appear as upgrades in existing nuclear power plants (NPPs) and in new plant designs. In order to assess the impact of digital system failures, quantifiable reliability models are needed along with data for digital systems that are compatible with existing probabilistic safety assessments (PSA). The paper focuses on the modelling of software failures of digital I and C systems in probabilistic assessments. An analysis of software faults, failures and effects is presented to derive relevant failure modes of system and application software for the PSA. The estimations of software failure probabilities are based on an analysis of the operating experience of TELEPERM registered XS (TXS). For the assessment of application software failures the analysis combines the use of the TXS operating experience at an application function level combined with conservative engineering judgments. Failure probabilities to actuate on demand and of spurious actuation of typical reactor protection application are estimated. Moreover, the paper gives guidelines for the modelling of software failures in the PSA. The strategy presented in this paper is generic and can be applied to different software platforms and their applications.

  4. Does International Migration Pay Off? The Labor Market Situation of Finnish Return Migrants Based on Longitudinal Register Data

    Directory of Open Access Journals (Sweden)

    Saara Koikkalainen

    2016-12-01

    Full Text Available International mobility is a form of flexible labor market adaptation available for young Nordic nationals who have the privilege of relatively easy return if life abroad does not work out. The article considers mobility as a labor market transition and examines the pre- and post-migration situation of two Finnish return migrant groups—those who lived abroad in 1999 and in 2004—based on longitudinal register data. It considers the consequences of return for an individual migrant: is it a form of failure in labor market integration in the country of destination or rather a sign of success whereby the skills, resources, and experiences gained abroad are brought back to the country of origin. Migrants who leave Finland nowadays often opt to move to other Nordic countries and are younger, more educated, and have a better socio-economic status than previous migrant generations. The article demonstrates that international migration does not deteriorate the returnees’ labor market status. While re-entry into the Finnish labor market may take some time and flexibility, mobility seems to pay off and have beneficial consequences: return migrants earn higher taxable incomes and have lower unemployment rates than their peers who only stayed in the national labor markets..

  5. Long term sickness absence and diabetes: a Danish register-based longitudinal study with up to 17 years of followup

    DEFF Research Database (Denmark)

    Nexø, Mette Andersen; Carlsen, Kathrine; Pedersen, Jacob

    Background and aims: The number of individuals with diabetes mellitus within the working age range is expected to rise. Type 1 and type 2 diabetes mellitus (diabetes) can have work related consequences such as decreased productivity, increased risks of sickness absence and early retirement...... year of diagnosis and in subsequent years. Materials and methods: The study was based on registers with up to 17 years of follow-up. In a working population (n=102.746) individuals with the diagnoses of type 1 or type 2 diabetes (n=3.325: women, n=1.987, men=1338) and individuals without diabetes (n=99.......421: women, n=73.332, men=26.089) were identified by Danish national registries of diagnosis (ICD-10 codes: E10.0-10.9, E11.0-E11.9, E12-E14) and prescribed medicine (ATC codes: A10A, A10B, A10BA02), in the period 1994 to 2011. We estimated the hazard ratios of transitions from work to LTSA (>3 consecutive...

  6. Cohort profile: The Swedish National Register of Urinary Bladder Cancer (SNRUBC) and the Bladder Cancer Data Base Sweden (BladderBaSe)

    Science.gov (United States)

    Häggström, Christel; Liedberg, Fredrik; Hagberg, Oskar; Aljabery, Firas; Ströck, Viveka; Hosseini, Abolfazl; Gårdmark, Truls; Sherif, Amir; Malmström, Per-Uno; Garmo, Hans; Jahnson, Staffan; Holmberg, Lars

    2017-01-01

    Purpose To monitor the quality of bladder cancer care, the Swedish National Register of Urinary Bladder Cancer (SNRUBC) was initiated in 1997. During 2015, in order to study trends in incidence, effects of treatment and survival of men and women with bladder cancer, we linked the SNRUBC to other national healthcare and demographic registers and constructed the Bladder Cancer Data Base Sweden (BladderBaSe). Participants The SNRUBC is a nationwide register with detailed information on 97% of bladder cancer cases in Sweden as compared with the Swedish Cancer Register. Participants in the SNRUBC have registered data on tumour characteristics at diagnosis, and for 98% of these treatment data have been captured. From 2009, the SNRUBC holds data on 88% of eligible participants for follow-up 5 years after diagnosis of non-muscle invasive bladder cancer, and from 2011, data on surgery details and complications for 85% of participants treated with radical cystectomy. The BladderBaSe includes all data in the SNRUBC from 1997 to 2014, and additional covariates and follow-up data from linked national register sources on comorbidity, socioeconomic factors, detailed information on readmissions and treatment side effects, and causes of death. Findings to date Studies based on data in the SNRUBC have shown inequalities in survival and treatment indication by gender, regions and hospital volume. The BladderBaSe includes 38 658 participants registered in SNRUBC with bladder cancer diagnosed from 1 January 1997 to 31 December 2014. The BladderBaSe initiators are currently in collaboration with researchers from the SNRUBC investigating different aspects of bladder cancer survival. Future plans The SNRUBC and the BladderBaSe project are open for collaborations with national and international research teams. Collaborators can submit proposals for studies and study files can be uploaded to servers for remote access and analysis. For more information, please contact the corresponding

  7. Infant and childhood neurodevelopmental outcomes following prenatal exposure to selective serotonin reuptake inhibitors: overview and design of a Finnish Register-Based Study (FinESSI

    Directory of Open Access Journals (Sweden)

    Malm Heli

    2012-12-01

    Full Text Available Abstract Background Experimental animal studies and one population-based study have suggested an increased risk for adverse neurodevelopmental outcome after prenatal exposure to SSRIs. We describe the methods and design of a population-based study examining the association between prenatal SSRI exposure and neurodevelopment until age 14. Methods and design This is a cohort study of national registers in Finland: the Medical Birth Register, the Register of Congenital Malformations, the Hospital Discharge Register including inpatient and outpatient data, the Drug Reimbursement Register, and the Population Register. The total study population includes 845,345 women and their live-born, singleton offspring aged 14 or younger and born during Jan 1st 1996-Dec 31st 2010. We will compare the prevalence of psychiatric and neurodevelopmental outcomes in offspring exposed prenatally to SSRIs to offspring exposed to prenatal depression and unexposed to SSRIs. Associations between exposure and outcome are assessed by statistical methods including specific modeling to account for correlated outcomes within families and differences in duration of follow-up between the exposure groups. Descriptive results. Of all pregnant women with pregnancy ending in delivery (n = 859,359, 1.9% used SSRIs. The prevalence of diagnosed depression and depression-related psychiatric disorders within one year before or during pregnancy was 1.7%. The cumulative incidence of registered psychiatric or neurodevelopmental disorders was 6.9% in 2010 among all offspring born during the study period (age range 0–14 years. Discussion The study has the potential for significant public health importance in providing information on prenatal exposure to SSRIs and long-term neurodevelopment.

  8. No evidence of a causal relationship between hypothyroidism and glaucoma: A Danish nationwide register-based cohort study

    Science.gov (United States)

    2018-01-01

    Background An interrelationship between hypothyroidism and glaucoma, due to a shared autoimmune background or based on deposition of mucopolysaccharides in the trabecular meshwork in the eye, has been suggested but is at present unsubstantiated. Therefore, our objective was to investigate, at a nationwide and population-based level, whether there is such an association. Subjects and methods Observational cohort study using record-linkage data from nationwide Danish health registers. 121,799 individuals diagnosed with a first episode of hypothyroidism were identified and were matched with 4 non-hypothyroid controls according to age and sex. Prevalence of glaucoma was recorded and cases and controls were followed over a mean of 7.1 years (range 0–17). Logistic and Cox regression models were used to assess the risk of glaucoma before and after the diagnosis of hypothyroidism, respectively. Results Overall, we found a higher prevalence of glaucoma in subjects with hypothyroidism as compared to controls (4.6% vs. 4.3%, p hypothyroidism, the odds ratio (OR) was significantly increased for glaucoma [1.09; 95% confidence interval (CI): 1.04–1.13]. Based on the Cox regression model, there was no increased risk of glaucoma after the diagnosis of hypothyroidism [hazard ratio (HR) 1.00; 95% CI: 0.96–1.06], and the HR decreased further after adjusting for pre-existing co-morbidity (0.88; 95% CI: 0.84–0.93). Conclusions There was an increased risk of glaucoma before but not after the diagnosis of hypothyroidism, suggesting that screening for glaucoma in hypothyroid individuals is unwarranted. PMID:29444121

  9. Fuzzy Matching Based on Gray-scale Difference for Quantum Images

    Science.gov (United States)

    Luo, GaoFeng; Zhou, Ri-Gui; Liu, XingAo; Hu, WenWen; Luo, Jia

    2018-05-01

    Quantum image processing has recently emerged as an essential problem in practical tasks, e.g. real-time image matching. Previous studies have shown that the superposition and entanglement of quantum can greatly improve the efficiency of complex image processing. In this paper, a fuzzy quantum image matching scheme based on gray-scale difference is proposed to find out the target region in a reference image, which is very similar to the template image. Firstly, we employ the proposed enhanced quantum representation (NEQR) to store digital images. Then some certain quantum operations are used to evaluate the gray-scale difference between two quantum images by thresholding. If all of the obtained gray-scale differences are not greater than the threshold value, it indicates a successful fuzzy matching of quantum images. Theoretical analysis and experiments show that the proposed scheme performs fuzzy matching at a low cost and also enables exponentially significant speedup via quantum parallel computation.

  10. Quantum secret sharing based on Smolin states alone

    International Nuclear Information System (INIS)

    He Guangping; Wang, Z D; Bai, Yankui

    2008-01-01

    It was indicated (Yu 2007 Phys. Rev. A 75 066301) that a previously proposed quantum secret sharing (QSS) protocol based on Smolin states (Augusiak 2006 Phys. Rev. A 73 012318) is insecure against an internal cheater. Here we build a different QSS protocol with Smolin states alone, and prove it to be secure against known cheating strategies. Thus we open a promising venue for building secure QSS using merely Smolin states, which is a typical kind of bound entangled states. We also propose a feasible scheme to implement the protocol experimentally

  11. A group signature scheme based on quantum teleportation

    International Nuclear Information System (INIS)

    Wen Xiaojun; Tian Yuan; Ji Liping; Niu Xiamu

    2010-01-01

    In this paper, we present a group signature scheme using quantum teleportation. Different from classical group signature and current quantum signature schemes, which could only deliver either group signature or unconditional security, our scheme guarantees both by adopting quantum key preparation, quantum encryption algorithm and quantum teleportation. Security analysis proved that our scheme has the characteristics of group signature, non-counterfeit, non-disavowal, blindness and traceability. Our quantum group signature scheme has a foreseeable application in the e-payment system, e-government, e-business, etc.

  12. A group signature scheme based on quantum teleportation

    Energy Technology Data Exchange (ETDEWEB)

    Wen Xiaojun; Tian Yuan; Ji Liping; Niu Xiamu, E-mail: wxjun36@gmail.co [Information Countermeasure Technique Research Institute, Harbin Institute of Technology, Harbin 150001 (China)

    2010-05-01

    In this paper, we present a group signature scheme using quantum teleportation. Different from classical group signature and current quantum signature schemes, which could only deliver either group signature or unconditional security, our scheme guarantees both by adopting quantum key preparation, quantum encryption algorithm and quantum teleportation. Security analysis proved that our scheme has the characteristics of group signature, non-counterfeit, non-disavowal, blindness and traceability. Our quantum group signature scheme has a foreseeable application in the e-payment system, e-government, e-business, etc.

  13. Optimal diabatic dynamics of Majorana-based quantum gates

    Science.gov (United States)

    Rahmani, Armin; Seradjeh, Babak; Franz, Marcel

    2017-08-01

    In topological quantum computing, unitary operations on qubits are performed by adiabatic braiding of non-Abelian quasiparticles, such as Majorana zero modes, and are protected from local environmental perturbations. In the adiabatic regime, with timescales set by the inverse gap of the system, the errors can be made arbitrarily small by performing the process more slowly. To enhance the performance of quantum information processing with Majorana zero modes, we apply the theory of optimal control to the diabatic dynamics of Majorana-based qubits. While we sacrifice complete topological protection, we impose constraints on the optimal protocol to take advantage of the nonlocal nature of topological information and increase the robustness of our gates. By using the Pontryagin's maximum principle, we show that robust equivalent gates to perfect adiabatic braiding can be implemented in finite times through optimal pulses. In our implementation, modifications to the device Hamiltonian are avoided. Focusing on thermally isolated systems, we study the effects of calibration errors and external white and 1 /f (pink) noise on Majorana-based gates. While a noise-induced antiadiabatic behavior, where a slower process creates more diabatic excitations, prohibits indefinite enhancement of the robustness of the adiabatic scheme, our fast optimal protocols exhibit remarkable stability to noise and have the potential to significantly enhance the practical performance of Majorana-based information processing.

  14. A register-based case-control study of health care utilization and costs in binge-eating disorder.

    Science.gov (United States)

    Watson, Hunna J; Jangmo, Andreas; Smith, Tosha; Thornton, Laura M; von Hausswolff-Juhlin, Yvonne; Madhoo, Manisha; Norring, Claes; Welch, Elisabeth; Wiklund, Camilla; Larsson, Henrik; Bulik, Cynthia M

    2018-05-01

    Capturing trends in healthcare utilization may help to improve efficiencies in the detection and diagnosis of illness, to plan service delivery, and to forecast future health expenditures. For binge-eating disorder (BED), issues include lengthy delays in detection and diagnosis, missed opportunities for recognition and treatment, and morbidity. The study objective was to compare healthcare utilization and expenditure in people with and without BED. A case-control design and nationwide registers were used. All individuals diagnosed with BED at eating disorder clinics in Sweden between 2005 and 2009 were included (N = 319, 97% female, M age = 22 years). Ten controls (N = 3190) were matched to each case on age-, sex-, and location of birth. Inpatient, hospital-based outpatient, and prescription medication utilization and expenditure were analyzed up to eight years before and four years after the index date (i.e., date of diagnosis of the BED case). Cases had significantly higher inpatient, hospital-based outpatient, and prescription medication utilization and expenditure compared with controls many years prior to and after diagnosis of BED. Utilization and expenditure for controls was relatively stable over time, but for cases followed an inverted U-shape and peaked at the index year. Care for somatic conditions normalized after the index year, but care for psychiatric conditions remained significantly higher. Individuals with BED had substantially higher healthcare utilization and costs in the years prior to and after diagnosis of BED. Since previous research shows a delay in diagnosis, findings indicate clear opportunities for earlier detection and clinical management. Training of providers in detection, diagnosis, and management may help curtail morbidity. A reduction in healthcare utilization was observed after BED diagnosis. This suggests that earlier diagnosis and treatment could improve long-term health outcomes and reduce the economic burden

  15. Registered nurses' perceptions of their professional work in nursing homes and home-based care: a focus group study.

    Science.gov (United States)

    Carlson, Elisabeth; Rämgård, Margareta; Bolmsjö, Ingrid; Bengtsson, Mariette

    2014-05-01

    In Sweden, as well as in most industrialised countries, an increasing older population is expected to create a growing demand for health care staff. Previous studies have pointed to lack of proficient medical and nursing staff specialised in geriatric care, which poses serious threats to the care of a vulnerable population. At the same time, there are studies describing elderly care as a low-status career choice, attracting neither nurses nor student nurses. Judging from previous research it was deemed important to explore how nurses in elderly care perceive their work, thus possibly provide vital knowledge that can guide nurse educators and unit managers as a means to promote a career in elderly care. The aim of the present study was to illuminate how nurses, working in nursing homes and home-based care, perceived their professional work. This was a qualitative study using focus groups. 30 registered nurses in seven focus groups were interviewed. The participants worked in nursing homes and home-based care for the elderly in rural areas and in a larger city in southern Sweden. The interviews were analysed in line with the tradition of naturalistic inquiry. Our findings illustrate how nurses working in elderly care perceived their professional work as holistic and respectful nursing. Three categories of professional work emerged during analysis: (1) establishing long-term relationships, (2) nursing beyond technical skills, and (3) balancing independence and a sense of loneliness. The findings are important as they represent positive alternatives to the somewhat prevailing view on elderly care as depressing and undemanding. Nurse educators might use the key aspects as good examples, thus influencing student nurses' attitudes towards elderly care in a positive way. Elderly care agencies might find them helpful when recruiting and retaining nurses to a much needed area. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Maternal and fetal characteristics affect discrepancies between pregnancy-dating methods: a population-based cross-sectional register study.

    Science.gov (United States)

    Kullinger, Merit; Wesström, Jan; Kieler, Helle; Skalkidou, Alkistis

    2017-01-01

    Gestational age is estimated by ultrasound using fetal size as a proxy for age, although variance in early growth affects reliability. The aim of this study was to identify characteristics associated with discrepancies between last menstrual period-based (EDD-LMP) and ultrasound-based (EDD-US) estimated delivery dates. We identified all singleton births (n = 1 201 679) recorded in the Swedish Medical Birth Register in 1995-2010, to assess the association between maternal/fetal characteristics and large negative and large positive discrepancies (EDD-LMP earlier than EDD-US and 10th percentile in the discrepancy distribution vs. EDD-LMP later than EDD-US and 90th percentile). Analyses were adjusted for age, parity, height, body mass index, smoking, and employment status. Women with a body mass index >40 kg/m 2 had the highest odds for large negative discrepancies (-9 to -20 days) [odds ratio (OR) 2.16, 95% CI 2.01-2.33]. Other factors associated with large negative discrepancies were: diabetes, young maternal age, multiparity, body mass index between 30 and 39.9 kg/m 2 or +1 SD), and unemployment. Several maternal and fetal characteristics were associated with discrepancies between dating methods. Systematic associations of discrepancies with maternal height, fetal sex, and partly obesity, may reflect an influence on the precision of the ultrasound estimate due to variance in early growth. © 2016 The Authors. Acta Obstetricia et Gynecologica Scandinavica published by John Wiley & Sons Ltd on behalf of Nordic Federation of Societies of Obstetrics and Gynecology (NFOG).

  17. Positive predictive value of a register-based algorithm using the Danish National Registries to identify suicidal events.

    Science.gov (United States)

    Gasse, Christiane; Danielsen, Andreas Aalkjaer; Pedersen, Marianne Giørtz; Pedersen, Carsten Bøcker; Mors, Ole; Christensen, Jakob

    2018-04-17

    It is not possible to fully assess intention of self-harm and suicidal events using information from administrative databases. We conducted a validation study of intention of suicide attempts/self-harm contacts identified by a commonly applied Danish register-based algorithm (DK-algorithm) based on hospital discharge diagnosis and emergency room contacts. Of all 101 530 people identified with an incident suicide attempt/self-harm contact at Danish hospitals between 1995 and 2012 using the DK-algorithm, we selected a random sample of 475 people. We validated the DK-algorithm against medical records applying the definitions and terminology of the Columbia Classification Algorithm of Suicide Assessment of suicidal events, nonsuicidal events, and indeterminate or potentially suicidal events. We calculated positive predictive values (PPVs) of the DK-algorithm to identify suicidal events overall, by gender, age groups, and calendar time. We retrieved medical records for 357 (75%) people. The PPV of the DK-algorithm to identify suicidal events was 51.5% (95% CI: 46.4-56.7) overall, 42.7% (95% CI: 35.2-50.5) in males, and 58.5% (95% CI: 51.6-65.1) in females. The PPV varied further across age groups and calendar time. After excluding cases identified via the DK-algorithm by unspecific codes of intoxications and injury, the PPV improved slightly (56.8% [95% CI: 50.0-63.4]). The DK-algorithm can reliably identify self-harm with suicidal intention in 52% of the identified cases of suicide attempts/self-harm. The PPVs could be used for quantitative bias analysis and implemented as weights in future studies to estimate the proportion of suicidal events among cases identified via the DK-algorithm. Copyright © 2018 John Wiley & Sons, Ltd.

  18. Quantum transport in nanowire-based hybrid devices

    Energy Technology Data Exchange (ETDEWEB)

    Guenel, Haci Yusuf

    2013-05-08

    We have studied the low-temperature transport properties of nanowires contacted by a normal metal as well as by superconducting electrodes. As a consequence of quantum coherence, we have demonstrated the electron interference effect in different aspects. The mesoscopic phase coherent transport properties were studied by contacting the semiconductor InAs and InSb nanowires with normal metal electrodes. Moreover, we explored the interaction of the microscopic quantum coherence of the nanowires with the macroscopic quantum coherence of the superconductors. In superconducting Nb contacted InAs nanowire junctions, we have investigated the effect of temperature, magnetic field and electric field on the supercurrent. Owing to relatively high critical temperature of superconducting Nb (T{sub c} ∝ 9 K), we have observed the supercurrent up to 4 K for highly doped nanowire-based junctions, while for low doped nanowire-based junctions a full control of the supercurrent was achieved. Due to low transversal dimension of the nanowires, we have found a monotonous decay of the critical current in magnetic field dependent measurements. The experimental results were analyzed within narrow junction model which has been developed recently. At high bias voltages, we have observed subharmonic energy gap structures as a consequence of multiple Andreev reflection. Some of the nanowires were etched, such that the superconducting Nb electrodes are connected to both ends of the nanowire rather than covering the surface of the nanowire. As a result of well defined nanowire-superconductor interfaces, we have examined quasiparticle interference effect in magnetotransport measurements. Furthermore, we have developed a new junction geometry, such that one of the superconducting Nb electrodes is replaced by a superconducting Al. Owing to the smaller critical magnetic field of superconducting Al (B{sub c} ∝ 15-50,mT), compared to superconducting Nb (B{sub c} ∝ 3 T), we were able to studied

  19. Quantum Image Steganography and Steganalysis Based On LSQu-Blocks Image Information Concealing Algorithm

    Science.gov (United States)

    A. AL-Salhi, Yahya E.; Lu, Songfeng

    2016-08-01

    Quantum steganography can solve some problems that are considered inefficient in image information concealing. It researches on Quantum image information concealing to have been widely exploited in recent years. Quantum image information concealing can be categorized into quantum image digital blocking, quantum image stereography, anonymity and other branches. Least significant bit (LSB) information concealing plays vital roles in the classical world because many image information concealing algorithms are designed based on it. Firstly, based on the novel enhanced quantum representation (NEQR), image uniform blocks clustering around the concrete the least significant Qu-block (LSQB) information concealing algorithm for quantum image steganography is presented. Secondly, a clustering algorithm is proposed to optimize the concealment of important data. Finally, we used Con-Steg algorithm to conceal the clustered image blocks. Information concealing located on the Fourier domain of an image can achieve the security of image information, thus we further discuss the Fourier domain LSQu-block information concealing algorithm for quantum image based on Quantum Fourier Transforms. In our algorithms, the corresponding unitary Transformations are designed to realize the aim of concealing the secret information to the least significant Qu-block representing color of the quantum cover image. Finally, the procedures of extracting the secret information are illustrated. Quantum image LSQu-block image information concealing algorithm can be applied in many fields according to different needs.

  20. Novel Schemes for Measurement-Based Quantum Computation

    International Nuclear Information System (INIS)

    Gross, D.; Eisert, J.

    2007-01-01

    We establish a framework which allows one to construct novel schemes for measurement-based quantum computation. The technique develops tools from many-body physics--based on finitely correlated or projected entangled pair states--to go beyond the cluster-state based one-way computer. We identify resource states radically different from the cluster state, in that they exhibit nonvanishing correlations, can be prepared using nonmaximally entangling gates, or have very different local entanglement properties. In the computational models, randomness is compensated in a different manner. It is shown that there exist resource states which are locally arbitrarily close to a pure state. We comment on the possibility of tailoring computational models to specific physical systems

  1. Novel schemes for measurement-based quantum computation.

    Science.gov (United States)

    Gross, D; Eisert, J

    2007-06-01

    We establish a framework which allows one to construct novel schemes for measurement-based quantum computation. The technique develops tools from many-body physics-based on finitely correlated or projected entangled pair states-to go beyond the cluster-state based one-way computer. We identify resource states radically different from the cluster state, in that they exhibit nonvanishing correlations, can be prepared using nonmaximally entangling gates, or have very different local entanglement properties. In the computational models, randomness is compensated in a different manner. It is shown that there exist resource states which are locally arbitrarily close to a pure state. We comment on the possibility of tailoring computational models to specific physical systems.

  2. Entanglement-based Free Space Quantum Cryptography in Daylight

    Science.gov (United States)

    Gerhardt, Ilja; Peloso, Matthew P.; Ho, Caleb; Lamas-Linares, Antia; Kurtsiefer, Christian

    2009-05-01

    In quantum key distribution (QKD) two families of protocols are established: One, based on preparing and sending approximations of single photons, the other based on measurements on entangled photon pairs, which allow to establish a secret key using less assumptions on the size of a Hilbert space. The larger optical bandwidth of photon pairs in comparison with light used for the first family makes establishing a free space link challenging. We present a complete entanglement based QKD system following the BBM92 protocol, which generates a secure key continuously 24 hours a day between distant parties. Spectral, spatial and temporal filtering schemes were introduced to a previous setup, suppressing more than 30,B of background. We are able to establish the link during daytime, and have developed an algorithm to start and maintain time synchronization with simple crystal oscillators.

  3. A highly efficient single-photon source based on a quantum dot in a photonic nanowire

    DEFF Research Database (Denmark)

    Claudon, Julien; Bleuse, Joel; Malik, Nitin Singh

    2010-01-01

    –4 or a semiconductor quantum dot5–7. Achieving a high extraction efficiency has long been recognized as a major issue, and both classical solutions8 and cavity quantum electrodynamics effects have been applied1,9–12. We adopt a different approach, based on an InAs quantum dot embedded in a GaAs photonic nanowire......The development of efficient solid-state sources of single photons is a major challenge in the context of quantum communication,optical quantum information processing and metrology1. Such a source must enable the implementation of a stable, single-photon emitter, like a colour centre in diamond2...

  4. The impact of ART on union dissolution: a register-based study in Denmark 1994-2010.

    Science.gov (United States)

    Martins, Mariana Veloso; Vassard, Ditte; Hougaard, Charlotte Ørsted; Schmidt, Lone

    2018-01-23

    Are couples initiating ART treatment at higher risk for future union dissolution compared to other couples? There is no effect of ART treatments in future marital dissolution over a period of 16 years when adjusting for all confounders. Findings regarding marital stability and infertility treatments have been sparse and controversial. While there is data showing higher divorce rates among women who go through infertility treatments, there is also some evidence of this experience bringing couples closer by forcing them to communicate more and to deal with the surrounding stigma. Using a population-based study and couple-level data, we investigated the extent to which ART treatment increases the risk for divorce/marital dissolution during up to 16 years of follow-up. Register-based national cohort study including all women registered with ART treatment in Denmark between 1 January 1994 and 30 September 2009 (n = 42 845). Marital/cohabiting status was confirmed by matching these women to partners who they were married to or shared an address with. To account for having a significant relationship at baseline (2 years), marital/cohabiting status was confirmed by accessing this variable before the establishment of the cohort back to 1 January 1992. A comparison group from the background population including five controls per case and matched to female age at baseline was prospectively sampled. Participants could change status during follow-up if they entered ART. The final sample had 148 972 couples, followed until marital dissolution, death of self/spouse, migration or until 31 December 2010. We used Cox regression models adjusting for female and male age, education, marriage, common child at baseline and live-born child during follow-up. At baseline, the majority of couples were married (69%). More non-ART couples opted for marriage (70% versus 64%; P status and having a common child at baseline (adj HR 0.83, 95% CI 0.80-0.86). However, when subsequent common children

  5. The Risk of Offspring Developing Substance Use Disorders when Exposed to One versus Two Parents with Alcohol Use Disorder: A Register-based Prospective Cohort Study

    DEFF Research Database (Denmark)

    Mellentin, Angelina Isabella; Brink, M; Bjerregaard, Lene Berit Skov

    2014-01-01

    .32-3.08) in the hazard ratios of SUD. Conclusion: Offspring’s of AUD parents had increased risks of SUD, with an additive parental risk of their offspring developing a SUD. This knowledge could have conceptual as well as practical implications in the clinical assessment, interventions and management of offspring exposed......-bases: the Civil Registration System, the Psychiatric Central Research Register, the National Patient Registry, the National Prescription Registry, the Fertility Database, and the Cause of Death Register. Adjusted hazard ratios (AHR) were calculated using multivariate Cox-regression models. Results: In all, 10...

  6. Proposal for a transmon-based quantum router

    NARCIS (Netherlands)

    Sala, Arnau; Blaauboer, M.

    2016-01-01

    We propose an implementation of a quantum router for microwave photons in a superconducting qubit architecture consisting of a transmon qubit, SQUIDs and a nonlinear capacitor. We model and analyze the dynamics of operation of the quantum switch using quantum Langevin equations in a scattering

  7. Quantum Illumination-Based Target Detection and Discrimination

    Science.gov (United States)

    2014-06-30

    photodiode with an estimated quantum efficiency of 85% and an ultralow-noise transimpedance amplifier . Compared with to our initial QI measurements...demonstrated high signal-to-noise ratio (SNR) quantum-illumination target detection in a lossy, noisy environment using an optical parametric amplifier ...Research Triangle Park, NC 27709-2211 quantum communication, target detection, entanglement, parametric downconversion, optical parametric amplifiers

  8. Depression, anxiety and quality of life in long-term survivors of malignant melanoma: a register-based cohort study.

    Directory of Open Access Journals (Sweden)

    Manfred E Beutel

    Full Text Available The purpose of the study was to determine anxiety and depression, quality of life, and their determinants in long-term survivors of malignant melanoma.In a state cancer registry a cohort of survivors of malignant melanoma was contacted via the physician registered. Of 1302 contactable patients, 689 (52.2% completed a questionnaire including the Patient Health Questionnaire with generalized anxiety (GAD-7 and depression (PHQ-9 and the EORTC Quality of Life Questionnaire (EORTC QLQ 30. Based on multiple regression analysis, predictors of quality of life and distress were identified. Comparison data were assessed in two waves of representative face-to-face household surveys of the adult German population.An average of 8.4 (5.7 to 12.2 years after diagnosis, distress was higher in women compared to men and in middle adulthood (vs. older patients. Symptoms were higher in women than in men, and there was a decline of functioning and increase of symptoms across the age range of both genders. Compared to the general population, there were slightly increased depression and anxiety (only women, but no impaired global quality of life. Yet, survivors evidenced functional decline and more physical symptoms. Distress and reduced quality of life were consistently predicted by lack of social support, fear of recurrence, pessimism and self-blame. Distress was increased by a family history of melanoma, and additional mental and somatic diseases.Overall, long-term survivors have adjusted well achieving a global quality of life comparable to the general population. Yet, compromised functional dimensions, physical symptoms and distress indicate the need for integrating psychooncological screening into oncological follow-up, which might be guided by predictors such as family history or social support. Further prospective study is needed to determine the course of adaptation to the disease and corroborate the risk factors identified.

  9. Pattern and predictors of sick leave among users of antidepressants: a Danish retrospective register-based cohort study.

    Science.gov (United States)

    Gasse, Christiane; Petersen, Liselotte; Chollet, Julien; Saragoussi, Delphine

    2013-12-01

    Depression is associated with work absenteeism, reduced productivity, and significant personal and societal economic burden. We describe patterns and determinants of sick leave among working Danish antidepressant users. Persons starting antidepressant treatment (January 1, 2004 through December 31, 2005) were identified from a representative 25% sample of the Danish population by linking Danish national registries. Inclusion criteria were age 18-64 years, being in the workforce the week prior to the first antidepressant prescription (index prescription, IP), and no antidepressant prescription in the year prior to the IP. Only sick leaves >2 weeks are centrally registered in Denmark and could be assessed. Cox regression analyses identified predictors of sick leave during the year following the IP, based on previous history of sick leave and clinical and socio-demographic baseline characteristics. In the cohort of 25,908 (59.7% women), sick leave prevalence increased from 37.5% (year prior to IP) to 45.3% (year after the IP); 30.7% were on sick leave for >8 weeks. Incidence peaked (35.5% of individuals) the week after the IP. Of persons with sick leave in the year before the IP, 62.7% were on sick leave the first week after the IP, vs 5.7% of those without previous sick leave. Predictors associated with increased risk of sick leave among those without previous sick leave were unemployment, female gender, age 25-54 years, couples with children, and vocational and higher intermediate education (including e.g. teachers and nurses). Reasons for sick leave, sick leaves of less than 14 days and the indications for antidepressant treatment were unknown. Sick leave was prevalent in persons starting new antidepressant use, often lasting >8 weeks. Previous sick leave was the strongest predictor of subsequent sick leave. © 2013 Elsevier B.V. All rights reserved.

  10. Over- and Under-Treatment of Hypothyroidism Is Associated with Excess Mortality: A Register-Based Cohort Study.

    Science.gov (United States)

    Lillevang-Johansen, Mads; Abrahamsen, Bo; Jørgensen, Henrik Løvendahl; Brix, Thomas Heiberg; Hegedüs, Laszlo

    2018-05-01

    This study investigated the association between hypothyroidism and mortality in both treated and untreated hypothyroid patients, and the consequences of over- and under-treatment with respect to mortality. This was a register-based cohort study of 235,168 individuals who had at least one serum thyrotropin (TSH) during 1995-2011 (median follow-up 7.2 years). Hypothyroidism was defined as at least two measurements of TSH >4.0 mIU/L within a half year spaced by at least 14 days, or one measurement of TSH >4.0 mIU/L and two filled prescriptions of levothyroxine the following year. All-cause mortality rates were calculated using multivariable Cox regression analysis adjusted for age, sex, and comorbidities using the Charlson Comorbidity Index. Mortality was increased in untreated hypothyroid individuals (n = 673; hazard ratio [HR] = 1.46 [confidence interval (CI) 1.26-1.69]; p 4.0 mIU/L and ≤10 mIU/L; p hypothyroidism (TSH >10 mIU/L; p = 0.002). Mortality was increased in both treated and untreated hypothyroid individuals for each six months a patient had increased TSH (HR = 1.05 [CI 1.02-1.07], p hypothyroidism) and age (older and younger than 65 years). Mortality was increased in untreated but not in treated hypothyroid individuals, independently of age and severity of hypothyroidism. Duration of decreased TSH in treated individuals had a greater impact on mortality than did duration of elevated TSH. These results stress the need for close monitoring of treatment in individuals receiving thyroid hormone replacement therapy.

  11. Depression and Anxiety in the Postpartum Period and Risk of Bipolar Disorder: A Danish Nationwide Register-Based Cohort Study.

    Science.gov (United States)

    Liu, Xiaoqin; Agerbo, Esben; Li, Jiong; Meltzer-Brody, Samantha; Bergink, Veerle; Munk-Olsen, Trine

    2017-05-01

    The first-onset affective episode requiring inpatient treatment in the postpartum period can be a marker of bipolar disorder, but it is unknown whether milder postpartum affective episodes are also indicators of underlying bipolarity. Therefore, we aimed to study whether women with a nonpsychotic postpartum affective episode treated with antidepressants have an increased risk of bipolar disorder. A register-based cohort study was conducted in Denmark of 122,622 parous women without psychiatric history who received a first-time antidepressant prescription during 1997-2012. We compared women with a first-time antidepressant prescription, which was our indicator of a first-onset affective disorder, within 1 year postpartum to women with a first-time antidepressant prescription outside the postpartum period. Our outcome was psychiatric contact for bipolar disorder (ICD-10 criteria) during follow-up, and we estimated hazard ratios using Cox regressions. The risk of bipolar disorder among women with a postpartum affective episode was higher than that in women with an affective episode outside the postpartum period. The risk of bipolar disorder was 1.66 (95% CI, 1.12-2.48) for postpartum antidepressant monotherapy and 10.15 (95% CI, 7.13-14.46) for postpartum antidepressant therapy plus a subsequent prescription for anxiolytics when these therapies were compared to antidepressant monotherapy outside the postpartum period. First-onset nonpsychotic postpartum affective disorder can be a marker of underlying bipolarity. Women who fill an antidepressant prescription following childbirth should be asked about hypomanic or manic symptoms and monitored long term. Clinically, when antidepressant monotherapy is ineffective or the individual woman experiences persistent and concerning symptoms, health professionals should consider a possible bipolar spectrum disorder. © Copyright 2017 Physicians Postgraduate Press, Inc.

  12. Comorbidity of autoimmune thyroid disorders and psychiatric disorders during the postpartum period: a Danish nationwide register-based cohort study.

    Science.gov (United States)

    Bergink, V; Pop, V J M; Nielsen, P R; Agerbo, E; Munk-Olsen, T; Liu, X

    2018-06-01

    The postpartum period is well-known risk period for the first onset of autoimmune thyroid disorders (AITDs) as well as first onset of psychiatric disorders. These two disorders are some of the most prevalent medical conditions postpartum, often misdiagnosed and disabling if left untreated. Our study was designed to explore the possible bidirectional association between AITDs and psychiatric disorders during the postpartum period. A population-based cohort study through linkage of Danish national registers, which comprised 312 779 women who gave birth to their first child during 1997-2010. We conducted Poisson regression analysis to estimate the incidence rate ratio (IRR) of psychiatric disorders among women with first-onset AITDs, the IRR of AITDs among women with first-onset psychiatric disorders as well as the overlap between these disorders using a comorbidity index. Women with first-onset AITDs postpartum were more likely to have first-onset psychiatric disorders than women who did not have postpartum AITDs (IRR = 1.88, 95% confidence interval (CI): 1.25-2.81). Women with first-onset postpartum psychiatric disorders had a higher risk of AITDs than women with no psychiatric disorders (IRR = 2.16, 95% CI: 1.45-3.20). The comorbidity index 2 years after delivery was 2.26 (95% CI: 1.61-2.90), indicating a comorbidity between first-onset AITDs and psychiatric disorders. First-onset AITDs and psychiatric disorders co-occur in the postpartum period, which has relevance to further studies on the etiologies of these disorders and why childbirth in particular triggers the onset.

  13. Physical activity behaviour in men with inflammatory joint disease: a cross-sectional register-based study.

    Science.gov (United States)

    Hammer, Nanna Maria; Midtgaard, Julie; Hetland, Merete Lund; Krogh, Niels Steen; Esbensen, Bente Appel

    2018-05-01

    Physical activity is recommended as an essential part of the non-pharmacological management of inflammatory joint disease, but previous research in this area has predominantly included women. The aim of this study was to examine physical activity behaviour in men with inflammatory joint disease. The study was conducted as a cross-sectional register-based study. Data on physical activity behaviour in men with RA, PsA and AS were matched with sociodemographic and clinical variables extracted from the DANBIO registry. Logistic regression analyses using multiple imputations were performed to investigate demographic and clinical variables associated with regular engagement in physical activity (moderate-vigorous ⩾2 h/week). Descriptive statistics were applied to explore motivation, barriers and preferences for physical activity. A total of 325 men were included of whom 129 (40%) engaged in regular physical activity. In univariate analyses, higher age, visual analogue scale (VAS) for pain, VAS fatigue, VAS patient's global, CRP level, disease activity, functional disability and current smoking were negatively associated with regular engagement in physical activity. In the final multivariable regression model only a high VAS fatigue score (⩾61 mm) (OR = 0.228; CI: 0.119, 0.436) remained significantly independently associated with regular physical activity. A majority of men with inflammatory joint disease do not meet the recommendations of regular physical activity. Both sociodemographic and clinical parameters were associated with engagement in physical activity, and fatigue especially seems to play a pivotal role in explaining suboptimal physical activity behaviour in this patient group.

  14. Comorbidities, treatment patterns and cost-of-illness of acromegaly in Sweden: a register-linkage population-based study.

    Science.gov (United States)

    Lesén, Eva; Granfeldt, Daniel; Houchard, Aude; Dinet, Jérôme; Berthon, Anthony; Olsson, Daniel S; Björholt, Ingela; Johannsson, Gudmundur

    2017-02-01

    Acromegaly is a complex endocrine disease with multiple comorbidities. Treatment to obtain biochemical remission includes surgery, medical therapy and radiation. We aimed to describe comorbidities, treatment patterns and cost-of-illness in patients with acromegaly in Sweden. A nationwide population-based study. Patients with acromegaly were identified and followed in national registers in Sweden. Longitudinal treatment patterns were assessed in patients diagnosed between July 2005 and December 2013. The cost-of-illness during 2013 was estimated from a societal perspective among patients diagnosed between 1987 and 2013. Among 358 patients with acromegaly (48% men, mean age at diagnosis 50.0 (s.d. 15.3) years) at least one comorbidity was reported in 81% (n = 290). The most common comorbidities were hypertension (40%, n = 142), neoplasms outside the pituitary (30%, n = 109), hypopituitarism (22%, n = 80) and diabetes mellitus (17%, n = 61). Acromegaly treatment was initiated on average 3.7 (s.d. 6.9) months after diagnosis. Among the 301 treated patients, the most common first-line treatments were surgery (60%, n = 180), somatostatin analogues (21%, n = 64) and dopamine agonists (14%, n = 41). After primary surgery, 24% (n = 44) received somatostatin analogues. The annual per-patient cost was €12 000; this was €8700 and €16 000 if diagnosed before or after July 2005, respectively. The cost-of-illness for acromegaly and its comorbidities was 77% from direct costs and 23% from production loss. The prevalence of comorbidity is high in patients with acromegaly. The most common first-line treatment in acromegalic patients was surgery followed by somatostatin analogues. The annual per-patient cost of acromegaly and its comorbidities was €12 000. © 2017 European Society of Endocrinology.

  15. Autoimmune diseases and severe infections as risk factors for schizophrenia: a 30-year population-based register study.

    Science.gov (United States)

    Benros, Michael E; Nielsen, Philip R; Nordentoft, Merete; Eaton, William W; Dalton, Susanne O; Mortensen, Preben B

    2011-12-01

    Autoimmune diseases have been associated with an increased risk of schizophrenia. It has been suggested that brain-reactive autoantibodies are part of the mechanisms behind this association. Furthermore, an increased permeability of the blood-brain barrier has been observed during periods of infection and inflammation. The authors therefore investigated whether autoimmune diseases combined with exposures to severe infections may increase the risk of schizophrenia Nationwide population-based registers in Denmark were linked, and the data were analyzed in a cohort study using survival analysis. All analyses were adjusted for calendar year, age, and sex. Incidence rate ratios and accompanying 95% confidence intervals (CIs) as measures of relative risk were used. A prior autoimmune disease increased the risk of schizophrenia by 29% (incidence rate ratio=1.29; 95% CI=1.18-1.41). Any history of hospitalization with infection increased the risk of schizophrenia by 60% (incidence rate ratio=1.60; 95% CI=1.56-1.64). When the two risk factors were combined, the risk of schizophrenia was increased even further (incidence rate ratio=2.25; 95% CI=2.04-2.46). The risk of schizophrenia was increased in a dose-response relationship, where three or more infections and an autoimmune disease were associated with an incidence rate ratio of 3.40 (95% CI=2.91-3.94). The results remained significant after adjusting for substance use disorders and family history of psychiatric disorders. Hospital contact with infection occurred in nearly 24% of individuals prior to a schizophrenia diagnosis. Autoimmune disease and the number of infections requiring hospitalization are risk factors for schizophrenia. The increased risk is compatible with an immunological hypothesis in subgroups of schizophrenia patients.

  16. Impact of preexisting depression on length of stay and discharge destination among patients hospitalized for acute stroke - Linked register-based study

    NARCIS (Netherlands)

    Nuyen, Jasper; Spreeuwenberg, Peter M.; Groenewegen, Peter P.; van den Bos, Geertrudis A. M.; Schellevis, Francois G.

    2008-01-01

    Background and Purpose-There exists limited knowledge regarding the relation between depression and healthcare utilization in stroke patients. The objective of this register-based study was to examine the impact of having preexisting depression at the time of hospital admission for acute stroke on

  17. Impact of Preexisting Depression on Length of Stay and Discharge Destination Among Patients Hospitalized for Acute Stroke : Linked Register-Based Study

    NARCIS (Netherlands)

    Nuyen, Jasper; Spreeuwenberg, Peter M.; Groenewegen, Peter P.; Bos, Geertrudis A.M. van den; Schellevis, Francois G.

    2008-01-01

    Background and Purpose—There exists limited knowledge regarding the relation between depression and healthcare utilization in stroke patients. The objective of this register-based study was to examine the impact of having preexisting depression at the time of hospital admission for acute stroke on

  18. Impact of preexisting depression on length of stay and discharge destination among patients hospitalized for acute stroke: linked register-based study.

    NARCIS (Netherlands)

    Nuyen, J.; Spreeuwenberg, P.; Groenewegen, P.P.; Bos, G.A.M. van den; Schellevis, F.G.

    2008-01-01

    Background and Purpose: There exists limited knowledge regarding the relation between depression and healthcare utilization in stroke patients. The objective of this register-based study was to examine the impact of having preexisting depression at the time of hospital admission for acute stroke on

  19. A probabilistic approach to quantum mechanics based on 'tomograms'

    International Nuclear Information System (INIS)

    Caponigro, M.; Mancini, S.; Man'ko, V.I.

    2006-01-01

    It is usually believed that a picture of Quantum Mechanics in terms of true probabilities cannot be given due to the uncertainty relations. Here we discuss a tomographic approach to quantum states that leads to a probability representation of quantum states. This can be regarded as a classical-like formulation of quantum mechanics which avoids the counterintuitive concepts of wave function and density operator. The relevant concepts of quantum mechanics are then reconsidered and the epistemological implications of such approach discussed. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  20. Quantum neural network based machine translator for Hindi to English.

    Science.gov (United States)

    Narayan, Ravi; Singh, V P; Chakraverty, S

    2014-01-01

    This paper presents the machine learning based machine translation system for Hindi to English, which learns the semantically correct corpus. The quantum neural based pattern recognizer is used to recognize and learn the pattern of corpus, using the information of part of speech of individual word in the corpus, like a human. The system performs the machine translation using its knowledge gained during the learning by inputting the pair of sentences of Devnagri-Hindi and English. To analyze the effectiveness of the proposed approach, 2600 sentences have been evaluated during simulation and evaluation. The accuracy achieved on BLEU score is 0.7502, on NIST score is 6.5773, on ROUGE-L score is 0.9233, and on METEOR score is 0.5456, which is significantly higher in comparison with Google Translation and Bing Translation for Hindi to English Machine Translation.

  1. The uniqueness of elderly care: registered nurses' experience as preceptors during clinical practice in nursing homes and home-based care.

    Science.gov (United States)

    Carlson, Elisabeth; Bengtsson, Mariette

    2014-04-01

    The expected shortage of registered nurses with an advanced degree as specialists in geriatric care or gerontology is imminent. Previous studies report that clinical practice where student nurses are supervised by registered nurses has a direct impact on how students perceive nursing as a profession and future career choice. Considering the anticipated need for well-educated and specialised nurses it is therefore, relevant as well as necessary to describe clinical learning with a focus on preceptorship in geriatric nursing care. This paper is a report of a study describing registered nurses' experience of precepting undergraduate student nurses during clinical practice in nursing homes and home-based care. A qualitative design, based on seven focus group interviews, was employed with 30 registered nurses with preceptor experience from nursing homes and home-based care for the elderly. Our findings present three precepting strategies that are unique to elderly care: preparing students for end of life care, facilitating a respectful approach to the older person and promoting creativity and independent work. The findings are discussed using a socio-cultural perspective and illustrate how communities of elderly practice can be valuable learning environments. © 2013.

  2. Model of a programmable quantum processing unit based on a quantum transistor effect

    Science.gov (United States)

    Ablayev, Farid; Andrianov, Sergey; Fetisov, Danila; Moiseev, Sergey; Terentyev, Alexandr; Urmanchev, Andrey; Vasiliev, Alexander

    2018-02-01

    In this paper we propose a model of a programmable quantum processing device realizable with existing nano-photonic technologies. It can be viewed as a basis for new high performance hardware architectures. Protocols for physical implementation of device on the controlled photon transfer and atomic transitions are presented. These protocols are designed for executing basic single-qubit and multi-qubit gates forming a universal set. We analyze the possible operation of this quantum computer scheme. Then we formalize the physical architecture by a mathematical model of a Quantum Processing Unit (QPU), which we use as a basis for the Quantum Programming Framework. This framework makes it possible to perform universal quantum computations in a multitasking environment.

  3. Comorbidity and temporal ordering of alcohol use disorders and other psychiatric disorders: results from a Danish register-based study

    DEFF Research Database (Denmark)

    Flensborg-Madsen, Trine; Mortensen, Erik Lykke; Knop, Joachim

    2009-01-01

    AUD in individuals who were already registered with another psychiatric disorder; these differences in risk were especially noticeable for anxiety disorders, personality disorders, and drug abuse. CONCLUSIONS: AUD is frequently comorbid with other psychiatric disorders, and it is likely that AUD...

  4. Novel artefact removal algorithms for co-registered EEG/fMRI based on selective averaging and subtraction

    NARCIS (Netherlands)

    de Munck, J.C.; van Houdt, P.J.; Goncalves, S.I.; van Wegen, E.E.H.; Ossenblok, P.P.W.

    2013-01-01

    Co-registered EEG and functional MRI (EEG/fMRI) is a potential clinical tool for planning invasive EEG in patients with epilepsy. In addition, the analysis of EEG/fMRI data provides a fundamental insight into the precise physiological meaning of both fMRI and EEG data. Routine application of

  5. Fractures in Individuals with and without a History of Infantile Autism. A Danish Register Study Based on Hospital Discharge Diagnoses

    Science.gov (United States)

    Mouridsen, Svend Erik; Rich, Bente; Isager, Torben

    2012-01-01

    We compared the prevalence and types of fractures in a clinical sample of 118 individuals diagnosed as children with infantile autism (IA) with 336 matched controls from the general population. All participants were screened through the nationwide Danish National Hospital Register. The average observation time was 30.3 years (range 27.3-30.4…

  6. Delusional disorder in old age and the risk of developing dementia: a nationwide register-based study

    DEFF Research Database (Denmark)

    Kørner, Alex; Lopez, Ana G; Lauritzen, Lise

    2008-01-01

    OBJECTIVE: To examine whether very late first-contact delusional disorder carries a risk for later development of dementia. METHODS: By linkage of the psychiatric and the somatic nationwide registers of all out- and in-patients with hospital contact in Denmark, we included all 60+ patients with f...

  7. The Impact and Evaluation of Two School-Based Interventions on Intention to Register an Organ Donation Preference

    Science.gov (United States)

    Reubsaet, A.; Brug, J.; Kitslaar, J.; Van Hooff, J. P.; van den Borne, H. W.

    2004-01-01

    The present paper describes the impact and evaluation of two intervention components--a video with group discussion and an interactive computer-tailored program--in order to encourage adolescents to register their organ donation preference. Studies were conducted in school during regular school hours. The video with group discussion in class had a…

  8. Realization of quantum Fourier transform over ZN

    International Nuclear Information System (INIS)

    Fu Xiang-Qun; Bao Wan-Su; Li Fa-Da; Zhang Yu-Chao

    2014-01-01

    Since the difficulty in preparing the equal superposition state of amplitude is 1/√N, we construct a quantile transform of quantum Fourier transform (QFT) over Z N based on the elementary transforms, such as Hadamard transform and Pauli transform. The QFT over Z N can then be realized by the quantile transform, and used to further design its quantum circuit and analyze the requirements for the quantum register and quantum gates. However, the transform needs considerable quantum computational resources and it is difficult to construct a high-dimensional quantum register. Hence, we investigate the design of t-bit quantile transform, and introduce the definition of t-bit semiclassical QFT over Z N . According to probability amplitude, we prove that the transform can be used to realize QFT over Z N and further design its quantum circuit. For this transform, the requirements for the quantum register, the one-qubit gate, and two-qubit gate reduce obviously when compared with those for the QFT over Z N . (general)

  9. Quantum information density scaling and qubit operation time constraints of CMOS silicon-based quantum computer architectures

    Science.gov (United States)

    Rotta, Davide; Sebastiano, Fabio; Charbon, Edoardo; Prati, Enrico

    2017-06-01

    Even the quantum simulation of an apparently simple molecule such as Fe2S2 requires a considerable number of qubits of the order of 106, while more complex molecules such as alanine (C3H7NO2) require about a hundred times more. In order to assess such a multimillion scale of identical qubits and control lines, the silicon platform seems to be one of the most indicated routes as it naturally provides, together with qubit functionalities, the capability of nanometric, serial, and industrial-quality fabrication. The scaling trend of microelectronic devices predicting that computing power would double every 2 years, known as Moore's law, according to the new slope set after the 32-nm node of 2009, suggests that the technology roadmap will achieve the 3-nm manufacturability limit proposed by Kelly around 2020. Today, circuital quantum information processing architectures are predicted to take advantage from the scalability ensured by silicon technology. However, the maximum amount of quantum information per unit surface that can be stored in silicon-based qubits and the consequent space constraints on qubit operations have never been addressed so far. This represents one of the key parameters toward the implementation of quantum error correction for fault-tolerant quantum information processing and its dependence on the features of the technology node. The maximum quantum information per unit surface virtually storable and controllable in the compact exchange-only silicon double quantum dot qubit architecture is expressed as a function of the complementary metal-oxide-semiconductor technology node, so the size scale optimizing both physical qubit operation time and quantum error correction requirements is assessed by reviewing the physical and technological constraints. According to the requirements imposed by the quantum error correction method and the constraints given by the typical strength of the exchange coupling, we determine the workable operation frequency

  10. Unwanted sexual attention at work and long-term sickness absence: a follow-up register-based study.

    Science.gov (United States)

    Hogh, Annie; Conway, Paul Maurice; Clausen, Thomas; Madsen, Ida Elisabeth Huitfeldt; Burr, Hermann

    2016-07-30

    The current understanding of the relationship between unwanted sexual attention at work and long-term sickness absence (LTSA) is limited for three reasons: 1) the under-researched role of unwanted sexual attention perpetrated by individuals outside the work organization; 2) a widespread use of self-reported measures of sickness absence, with an unclear identification of sickness absence episodes of long duration; 3) the cross-sectional design of most existing studies. The aim of this study was therefore to investigate the relationship between self-reported unwanted sexual attention at work and subsequent LTSA (≥3 weeks), stratifying by gender and source of exposure (i.e., colleagues, managers and/or subordinates vs. clients/customers/patients). This prospective study is based on a pooled sample of 14,605 employees from three Danish surveys conducted in 2000, 2004 and 2005, providing a total of 19,366 observations. A single questionnaire-based item was used to assess exposure to unwanted sexual attention. The pooled dataset was merged with Danish register data on LTSA. The risk of first-onset episode of LTSA (up to 18 months after baseline) in connection with unwanted sexual attention was examined using Cox proportional hazards models. We estimated Hazard ratios (HR) and 95 % confidence intervals (95 % CI) adjusted for age, influence at work, work pace, occupational group and mode of data collection. We also adjusted for repeated measures from individual respondents by stratifying the Cox models by wave of survey. Unwanted sexual attention from colleagues, managers and/or subordinates predicted LTSA among men (HR 2.66; 95 % CI 1.42-5.00). Among women, an elevated but non-statistically significant risk of LTSA (HR 1.18; 95 % CI 0.65-2.14) was found. Unwanted sexual attention from clients/customers/patients did not predict LTSA, neither among men nor among women. The findings indicate a significantly elevated risk of LTSA, among men only, in relation to

  11. Unwanted sexual attention at work and long-term sickness absence: a follow-up register-based study

    Directory of Open Access Journals (Sweden)

    Annie Hogh

    2016-07-01

    Full Text Available Abstract Background The current understanding of the relationship between unwanted sexual attention at work and long-term sickness absence (LTSA is limited for three reasons: 1 the under-researched role of unwanted sexual attention perpetrated by individuals outside the work organization; 2 a widespread use of self-reported measures of sickness absence, with an unclear identification of sickness absence episodes of long duration; 3 the cross-sectional design of most existing studies. The aim of this study was therefore to investigate the relationship between self-reported unwanted sexual attention at work and subsequent LTSA (≥3 weeks, stratifying by gender and source of exposure (i.e., colleagues, managers and/or subordinates vs. clients/customers/patients. Methods This prospective study is based on a pooled sample of 14,605 employees from three Danish surveys conducted in 2000, 2004 and 2005, providing a total of 19,366 observations. A single questionnaire-based item was used to assess exposure to unwanted sexual attention. The pooled dataset was merged with Danish register data on LTSA. The risk of first-onset episode of LTSA (up to 18 months after baseline in connection with unwanted sexual attention was examined using Cox proportional hazards models. We estimated Hazard ratios (HR and 95 % confidence intervals (95 % CI adjusted for age, influence at work, work pace, occupational group and mode of data collection. We also adjusted for repeated measures from individual respondents by stratifying the Cox models by wave of survey. Results Unwanted sexual attention from colleagues, managers and/or subordinates predicted LTSA among men (HR 2.66; 95 % CI 1.42-5.00. Among women, an elevated but non-statistically significant risk of LTSA (HR 1.18; 95 % CI 0.65-2.14 was found. Unwanted sexual attention from clients/customers/patients did not predict LTSA, neither among men nor among women. Conclusions The findings indicate a significantly

  12. Disease burden of herpes zoster in Sweden - predominance in the elderly and in women - a register based study

    Science.gov (United States)

    2013-01-01

    Background The herpes zoster burden of disease in Sweden is not well investigated. There is no Swedish immunization program to prevent varicella zoster virus infections. A vaccine against herpes zoster and its complications is now available. The aim of this study was to estimate the herpes zoster burden of disease and to establish a pre-vaccination baseline of the minimum incidence of herpes zoster. Methods Data were collected from the Swedish National Health Data Registers including the Patient Register, the Pharmacy Register, and the Cause of Death Register. The herpes zoster burden of disease in Sweden was estimated by analyzing the overall, and age and gender differences in the antiviral prescriptions, hospitalizations and complications during 2006-2010 and mortality during 2006-2009. Results Annually, 270 per 100,000 persons received antiviral treatment for herpes zoster, and the prescription rate increased with age. It was approximately 50% higher in females than in males in the age 50+ population (rate ratio 1.39; 95% CI, 1.22 to 1.58). The overall hospitalization rate for herpes zoster was 6.9/100,000 with an approximately three-fold increase for patients over 80 years of age compared to the age 70-79 group. A gender difference in hospitalization rates was observed: 8.1/100,000 in females and 5.6/100,000 in males. Herpes zoster, with a registered complication, was found in about one third of the hospitalized patients and the most common complications involved the peripheral and central nervous systems. Death due to herpes zoster was a rare event. Conclusions The results of this study demonstrate the significant burden of herpes zoster disease in the pre-zoster vaccination era. A strong correlation with age in the herpes zoster- related incidence, hospitalization, complications, and mortality rates was found. In addition, the study provides further evidence of the female predominance in herpes zoster disease. PMID:24330510

  13. Countrywise results of total hip replacement An analysis of 438,733 hips based on the Nordic Arthroplasty Register Association database

    DEFF Research Database (Denmark)

    Makela, K. T.; Matilainen, M.; Pulkkinen, P.

    2014-01-01

    Background and purpose An earlier Nordic Arthroplasty Register Association (NARA) report on 280,201 total hip replacements (THRs) based on data from 1995-2006, from Sweden, Norway, and Denmark, was published in 2009. The present study assessed THR survival according to country, based on the NARA.......36-0.98) year of follow-up. Interpretation The differences in THR survival rates were considerable, with inferior results in Finland. Brand-level comparison of THRs in Nordic countries will be required....

  14. Does a Caesarean section increase the time to a second live birth? A register-based cohort study.

    Science.gov (United States)

    O'Neill, Sinéad M; Khashan, Ali S; Henriksen, Tine B; Kenny, Louise C; Kearney, Patricia M; Mortensen, Preben B; Greene, Richard A; Agerbo, Esben

    2014-11-01

    Does a primary Caesarean section influence the rate of, and time to, subsequent live birth compared with vaginal delivery? Caesarean section was associated with a reduction in the rate of subsequent live birth, particularly among elective and maternal-requested Caesareans indicating maternal choice plays a role. Several studies have examined the relationship between Caesarean section and subsequent birth rate with conflicting results primarily due to poor epidemiological methods. This Danish population register-based cohort study covered the period from 1982 to 2010 (N = 832 996). All women with index live births were followed until their subsequent live birth or censored (maternal death, emigration or study end) using Cox regression models. In all 577 830 (69%) women had a subsequent live birth. Women with any type of Caesarean had a reduced rate of subsequent live birth (hazard ratio [HR] 0.86, 95% confidence intervals [CI] 0.85, 0.87) compared with spontaneous vaginal delivery. This effect was consistent when analyses were stratified by type of Caesarean: emergency (HR 0.87, 95% CI 0.86, 0.88), elective (HR 0.83, 95% CI 0.82, 0.84) and maternal-requested (HR 0.61, 95% CI 0.57, 0.66) and in the extensive sub-analyses performed. Lack of biological data to measure a woman's fertility is a major limitation of the current study. Unmeasured confounding and limited availability of data (maternal BMI, smoking, access to fertility services and maternal-requested Caesarean section) as well as changes in maternity care over time may also influence the findings. This is the largest study to date and shows that Caesarean section is most likely not causally related to a reduction in fertility. Maternal choice to delay or avoid childbirth is the most plausible explanation. Our findings are generalizable to other middle- to high-income countries; however, cross country variations in Caesarean section rates and social or cultural differences are acknowledged. Funding was

  15. Simulation of quantum dynamics based on the quantum stochastic differential equation.

    Science.gov (United States)

    Li, Ming

    2013-01-01

    The quantum stochastic differential equation derived from the Lindblad form quantum master equation is investigated. The general formulation in terms of environment operators representing the quantum state diffusion is given. The numerical simulation algorithm of stochastic process of direct photodetection of a driven two-level system for the predictions of the dynamical behavior is proposed. The effectiveness and superiority of the algorithm are verified by the performance analysis of the accuracy and the computational cost in comparison with the classical Runge-Kutta algorithm.

  16. Can the impact of gender equality on health be measured? a cross-sectional study comparing measures based on register data with individual survey-based data

    Directory of Open Access Journals (Sweden)

    Sörlin Ann

    2012-09-01

    Full Text Available Abstract Background The aim of this study was to investigate potential associations between gender equality at work and self-rated health. Methods 2861 employees in 21 companies were invited to participate in a survey. The mean response rate was 49.2%. The questionnaire contained 65 questions, mainly on gender equality and health. Two logistic regression analyses were conducted to assess associations between (i self-rated health and a register-based company gender equality index (OGGI, and (ii self-rated health and self-rated gender equality at work. Results Even though no association was found between the OGGI and health, women who rated their company as “completely equal” or “quite equal” had higher odds of reporting “good health” compared to women who perceived their company as “not equal” (OR = 2.8, 95% confidence interval = 1.4 – 5.5 and OR = 2.73, 95% CI = 1.6-4.6. Although not statistically significant, we observed the same trends in men. The results were adjusted for age, highest education level, income, full or part-time employment, and type of company based on the OGGI. Conclusions No association was found between gender equality in companies, measured by register-based index (OGGI, and health. However, perceived gender equality at work positively affected women’s self-rated health but not men’s. Further investigations are necessary to determine whether the results are fully credible given the contemporary health patterns and positions in the labour market of women and men or whether the results are driven by selection patterns.

  17. Can the impact of gender equality on health be measured? A cross-sectional study comparing measures based on register data with individual survey-based data.

    Science.gov (United States)

    Sörlin, Ann; Öhman, Ann; Ng, Nawi; Lindholm, Lars

    2012-09-17

    The aim of this study was to investigate potential associations between gender equality at work and self-rated health. 2861 employees in 21 companies were invited to participate in a survey. The mean response rate was 49.2%. The questionnaire contained 65 questions, mainly on gender equality and health. Two logistic regression analyses were conducted to assess associations between (i) self-rated health and a register-based company gender equality index (OGGI), and (ii) self-rated health and self-rated gender equality at work. Even though no association was found between the OGGI and health, women who rated their company as "completely equal" or "quite equal" had higher odds of reporting "good health" compared to women who perceived their company as "not equal" (OR = 2.8, 95% confidence interval = 1.4 - 5.5 and OR = 2.73, 95% CI = 1.6-4.6). Although not statistically significant, we observed the same trends in men. The results were adjusted for age, highest education level, income, full or part-time employment, and type of company based on the OGGI. No association was found between gender equality in companies, measured by register-based index (OGGI), and health. However, perceived gender equality at work positively affected women's self-rated health but not men's. Further investigations are necessary to determine whether the results are fully credible given the contemporary health patterns and positions in the labour market of women and men or whether the results are driven by selection patterns.

  18. Quantum-Secret-Sharing Scheme Based on Local Distinguishability of Orthogonal Seven-Qudit Entangled States

    Science.gov (United States)

    Liu, Cheng-Ji; Li, Zhi-Hui; Bai, Chen-Ming; Si, Meng-Meng

    2018-02-01

    The concept of judgment space was proposed by Wang et al. (Phys. Rev. A 95, 022320, 2017), which was used to study some important properties of quantum entangled states based on local distinguishability. In this study, we construct 15 kinds of seven-qudit quantum entangled states in the sense of permutation, calculate their judgment space and propose a distinguishability rule to make the judgment space more clearly. Based on this rule, we study the local distinguishability of the 15 kinds of seven-qudit quantum entangled states and then propose a ( k, n) threshold quantum secret sharing scheme. Finally, we analyze the security of the scheme.

  19. Proposed Robust Entanglement-Based Magnetic Field Sensor Beyond the Standard Quantum Limit.

    Science.gov (United States)

    Tanaka, Tohru; Knott, Paul; Matsuzaki, Yuichiro; Dooley, Shane; Yamaguchi, Hiroshi; Munro, William J; Saito, Shiro

    2015-10-23

    Recently, there have been significant developments in entanglement-based quantum metrology. However, entanglement is fragile against experimental imperfections, and quantum sensing to beat the standard quantum limit in scaling has not yet been achieved in realistic systems. Here, we show that it is possible to overcome such restrictions so that one can sense a magnetic field with an accuracy beyond the standard quantum limit even under the effect of decoherence, by using a realistic entangled state that can be easily created even with current technology. Our scheme could pave the way for the realizations of practical entanglement-based magnetic field sensors.

  20. Quantum-based Atomistic Simulation of Transition Metals

    International Nuclear Information System (INIS)

    Moriarty, J A; Benedict, L X; Glosli, J N; Hood, R Q; Orlikowski, D A; Patel, M V; Soderlind, P; Streitz, F H; Tang, M; Yang, L H

    2005-01-01

    First-principles generalized pseudopotential theory (GPT) provides a fundamental basis for transferable multi-ion interatomic potentials in d-electron transition metals within density-functional quantum mechanics. In mid-period bcc metals, where multi-ion angular forces are important to structural properties, simplified model GPT or MGPT potentials have been developed based on canonical d bands to allow analytic forms and large-scale atomistic simulations. Robust, advanced-generation MGPT potentials have now been obtained for Ta and Mo and successfully applied to a wide range of structural, thermodynamic, defect and mechanical properties at both ambient and extreme conditions of pressure and temperature. Recent algorithm improvements have also led to a more general matrix representation of MGPT beyond canonical bands allowing increased accuracy and extension to f-electron actinide metals, an order of magnitude increase in computational speed, and the current development of temperature-dependent potentials

  1. Free-space communication based on quantum cascade laser

    International Nuclear Information System (INIS)

    Liu Chuanwei; Zhai Shenqiang; Zhang Jinchuan; Zhou Yuhong; Jia Zhiwei; Liu Fengqi; Wang Zhanguo

    2015-01-01

    A free-space communication based on a mid-infrared quantum cascade laser (QCL) is presented. A room-temperature continuous-wave distributed-feedback (DFB) QCL combined with a mid-infrared detector comprise the basic unit of the communication system. Sinusoidal signals at a highest frequency of 40 MHz and modulated video signals with a carrier frequency of 30 MHz were successfully transmitted with this experimental setup. Our research has provided a proof-of-concept demonstration of space optical communication application with QCL. The highest operation frequency of our setup was determined by the circuit-limited modulation bandwidth. A high performance communication system can be obtained with improved modulation circuit system. (paper)

  2. Scintillation properties of quantum-dot doped styrene based plastic scintillators

    International Nuclear Information System (INIS)

    Park, J.M.; Kim, H.J.; Hwang, Y.S.; Kim, D.H.; Park, H.W.

    2014-01-01

    We fabricated quantum-dot doped plastic scintillators in order to control the emission wavelength. We studied the characterization of the quantum-dots (CdSe/ZnS) and PPO (2, 5-diphenyloxazole) doped styrene based plastic scintillators. PPO is usually used as a dopant to enhance the scintillation properties of organic scintillators with a maximum emission wavelength of 380 nm. In order to study the scintillation properties of the quantum-dots doped plastic scintillators, the samples were irradiated with X-ray, photon, and 45 MeV proton beams. We observed that only PPO doped plastic scintillators shows a luminescence peak around 380 nm. However, both the quantum-dots and PPO doped plastic scintillators shows luminescence peaks around 380 nm and 520 nm. Addition of quantum-dots had shifted the luminescence spectrum from 380 nm (PPO) toward the region of 520 nm (Quantum-dots). Emissions with wavelength controllable plastic scintillators can be matched to various kinds of photosensors such as photomultiplier tubes, photo-diodes, avalanche photo-diodes, and CCDs, etc. Also quantum-dots doped plastic scintillator, which is irradiated 45 MeV proton beams, shows that the light yield of quantum-dots doped plastic scintillator is increases as quantum-dots doping concentration increases at 520 nm. And also the plastic scintillators were irradiated with Cs-137 γ-ray for measuring fluorescence decay time. -- Highlights: • Quantum-dot doped plastic scintillator is grown by the thermal polymerization method. • Quantum-dot doped plastic scintillators can control the emission wavelength to match with photo-sensor. • Quantum-dots and PPO doped plastic scintillators emitted luminescence peaks around 380 nm and 520 nm. • We observed the energy transfer from PPO to quantum-dot in the quantum-dot doped plastic scintillator

  3. Scintillation properties of quantum-dot doped styrene based plastic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Park, J.M.; Kim, H.J., E-mail: hongjooknu@gmail.com; Hwang, Y.S.; Kim, D.H.; Park, H.W.

    2014-02-15

    We fabricated quantum-dot doped plastic scintillators in order to control the emission wavelength. We studied the characterization of the quantum-dots (CdSe/ZnS) and PPO (2, 5-diphenyloxazole) doped styrene based plastic scintillators. PPO is usually used as a dopant to enhance the scintillation properties of organic scintillators with a maximum emission wavelength of 380 nm. In order to study the scintillation properties of the quantum-dots doped plastic scintillators, the samples were irradiated with X-ray, photon, and 45 MeV proton beams. We observed that only PPO doped plastic scintillators shows a luminescence peak around 380 nm. However, both the quantum-dots and PPO doped plastic scintillators shows luminescence peaks around 380 nm and 520 nm. Addition of quantum-dots had shifted the luminescence spectrum from 380 nm (PPO) toward the region of 520 nm (Quantum-dots). Emissions with wavelength controllable plastic scintillators can be matched to various kinds of photosensors such as photomultiplier tubes, photo-diodes, avalanche photo-diodes, and CCDs, etc. Also quantum-dots doped plastic scintillator, which is irradiated 45 MeV proton beams, shows that the light yield of quantum-dots doped plastic scintillator is increases as quantum-dots doping concentration increases at 520 nm. And also the plastic scintillators were irradiated with Cs-137 γ-ray for measuring fluorescence decay time. -- Highlights: • Quantum-dot doped plastic scintillator is grown by the thermal polymerization method. • Quantum-dot doped plastic scintillators can control the emission wavelength to match with photo-sensor. • Quantum-dots and PPO doped plastic scintillators emitted luminescence peaks around 380 nm and 520 nm. • We observed the energy transfer from PPO to quantum-dot in the quantum-dot doped plastic scintillator.

  4. Quantum image pseudocolor coding based on the density-stratified method

    Science.gov (United States)

    Jiang, Nan; Wu, Wenya; Wang, Luo; Zhao, Na

    2015-05-01

    Pseudocolor processing is a branch of image enhancement. It dyes grayscale images to color images to make the images more beautiful or to highlight some parts on the images. This paper proposes a quantum image pseudocolor coding scheme based on the density-stratified method which defines a colormap and changes the density value from gray to color parallel according to the colormap. Firstly, two data structures: quantum image GQIR and quantum colormap QCR are reviewed or proposed. Then, the quantum density-stratified algorithm is presented. Based on them, the quantum realization in the form of circuits is given. The main advantages of the quantum version for pseudocolor processing over the classical approach are that it needs less memory and can speed up the computation. Two kinds of examples help us to describe the scheme further. Finally, the future work are analyzed.

  5. Comment on ‘Authenticated quantum secret sharing with quantum dialogue based on Bell states’

    Science.gov (United States)

    Gao, Gan; Wang, Yue; Wang, Dong; Ye, Liu

    2018-02-01

    In the paper (2016 Phys. Scr. 91 085101), Abulkasim et al proposed a authenticated quantum secret sharing scheme. We study the security of the multiparty case in the proposed scheme and find that it is not secure.

  6. National Register Historic Districts

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The National Register Historic District layer is a shape file showing the boundaries of Historic Districts that are listed on the National Register of Historic Places.

  7. Recent advances in exciton-based quantum information processing in quantum dot nanostructures

    International Nuclear Information System (INIS)

    Krenner, Hubert J; Stufler, Stefan; Sabathil, Matthias; Clark, Emily C; Ester, Patrick; Bichler, Max; Abstreiter, Gerhard; Finley, Jonathan J; Zrenner, Artur

    2005-01-01

    Recent experimental developments in the field of semiconductor quantum dot (QD) spectroscopy are discussed. Firstly, we report about single QD exciton two-level systems and their coherent properties in terms of single-qubit manipulations. In the second part, we report on coherent quantum coupling in a prototype 'two-qubit' system consisting of a vertically stacked pair of QDs. The interaction can be tuned in such QD molecule devices using an applied voltage as external parameter

  8. A secure quantum group signature scheme based on Bell states

    International Nuclear Information System (INIS)

    Zhang Kejia; Song Tingting; Zuo Huijuan; Zhang Weiwei

    2013-01-01

    In this paper, we propose a new secure quantum group signature with Bell states, which may have applications in e-payment system, e-government, e-business, etc. Compared with the recent quantum group signature protocols, our scheme is focused on the most general situation in practice, i.e. only the arbitrator is trusted and no intermediate information needs to be stored in the signing phase to ensure the security. Furthermore, our scheme has achieved all the characteristics of group signature—anonymity, verifiability, traceability, unforgetability and undeniability, by using some current developed quantum and classical technologies. Finally, a feasible security analysis model for quantum group signature is presented. (paper)

  9. Transitions in the computational power of thermal states for measurement-based quantum computation

    International Nuclear Information System (INIS)

    Barrett, Sean D.; Bartlett, Stephen D.; Jennings, David; Doherty, Andrew C.; Rudolph, Terry

    2009-01-01

    We show that the usefulness of the thermal state of a specific spin-lattice model for measurement-based quantum computing exhibits a transition between two distinct 'phases' - one in which every state is a universal resource for quantum computation, and another in which any local measurement sequence can be simulated efficiently on a classical computer. Remarkably, this transition in computational power does not coincide with any phase transition, classical, or quantum in the underlying spin-lattice model.

  10. Cohort profile: The Swedish National Register of Urinary Bladder Cancer (SNRUBC) and the Bladder Cancer Data Base Sweden (BladderBaSe).

    Science.gov (United States)

    Häggström, Christel; Liedberg, Fredrik; Hagberg, Oskar; Aljabery, Firas; Ströck, Viveka; Hosseini, Abolfazl; Gårdmark, Truls; Sherif, Amir; Malmström, Per-Uno; Garmo, Hans; Jahnson, Staffan; Holmberg, Lars

    2017-09-27

    To monitor the quality of bladder cancer care, the Swedish National Register of Urinary Bladder Cancer (SNRUBC) was initiated in 1997. During 2015, in order to study trends in incidence, effects of treatment and survival of men and women with bladder cancer, we linked the SNRUBC to other national healthcare and demographic registers and constructed the Bladder Cancer Data Base Sweden (BladderBaSe). The SNRUBC is a nationwide register with detailed information on 97% of bladder cancer cases in Sweden as compared with the Swedish Cancer Register. Participants in the SNRUBC have registered data on tumour characteristics at diagnosis, and for 98% of these treatment data have been captured. From 2009, the SNRUBC holds data on 88% of eligible participants for follow-up 5 years after diagnosis of non-muscle invasive bladder cancer, and from 2011, data on surgery details and complications for 85% of participants treated with radical cystectomy. The BladderBaSe includes all data in the SNRUBC from 1997 to 2014, and additional covariates and follow-up data from linked national register sources on comorbidity, socioeconomic factors, detailed information on readmissions and treatment side effects, and causes of death. Studies based on data in the SNRUBC have shown inequalities in survival and treatment indication by gender, regions and hospital volume. The BladderBaSe includes 38 658 participants registered in SNRUBC with bladder cancer diagnosed from 1 January 1997 to 31 December 2014. The BladderBaSe initiators are currently in collaboration with researchers from the SNRUBC investigating different aspects of bladder cancer survival. The SNRUBC and the BladderBaSe project are open for collaborations with national and international research teams. Collaborators can submit proposals for studies and study files can be uploaded to servers for remote access and analysis. For more information, please contact the corresponding author. © Article author(s) (or their employer

  11. On the photonic implementation of universal quantum gates, bell states preparation circuit and quantum LDPC encoders and decoders based on directional couplers and HNLF.

    Science.gov (United States)

    Djordjevic, Ivan B

    2010-04-12

    The Bell states preparation circuit is a basic circuit required in quantum teleportation. We describe how to implement it in all-fiber technology. The basic building blocks for its implementation are directional couplers and highly nonlinear optical fiber (HNLF). Because the quantum information processing is based on delicate superposition states, it is sensitive to quantum errors. In order to enable fault-tolerant quantum computing the use of quantum error correction is unavoidable. We show how to implement in all-fiber technology encoders and decoders for sparse-graph quantum codes, and provide an illustrative example to demonstrate this implementation. We also show that arbitrary set of universal quantum gates can be implemented based on directional couplers and HNLFs.

  12. Quantum dot infrared photodetectors based on indium phosphide

    International Nuclear Information System (INIS)

    Gebhard, T.

    2011-01-01

    The subject of this work is a systematic study of quantum dot infrared photodetectors based on indium-phosphide substrate by means of various spectroscopic and electronic measurement methods in order to understand the physical and technological processes. This enables a concise definition of strategies in order to realize next generation devices in this material system and to gain overall progress in the research field of quantum dot infrared photodetectors. The interpretation of the experimental results is supported by analytical and numerical simulations. The samples, grown by collaboration partners, were characterized using differential transmission and fast Fourier transform infrared spectroscopy, with a special emphasis on the latter one. Therefore, samples both in wedged waveguide geometry and samples with gold coated mesa structures have been processed. A large part of the discussion is dedicated to the current voltage characteristic of the devices, due to its large importance for device optimization, i.e. the reduction of the dark current plays a crucial role in the research field of high temperature infrared photon-detection. Further, results of photoluminescence measurements, performed by collaboration partners, have been used in order to attain a more complete picture of the samples' electronic band structure and in order to obtain complementary information with respect to other measurement methods applied within the experimental work and the simulation of the structures. In agreement to the simulations, a photocurrent response was observed at 6 and at 12 μm up to a temperature of 80 K, depending on the samples' design. The principle of parameter scaling was applied to the samples, in order to assign physical effects either to details in the samples' design or to technological quality aspects, i.e. the doping level and the thickness of the capping layer was varied. In addition to that a quantum well was introduced within a series of samples in order to

  13. Recruiting former melanoma patients via hospitals in comparison to office-based dermatologists in a register-based cohort study that required indirect contact

    Directory of Open Access Journals (Sweden)

    S. R. Zeissig

    2017-11-01

    Full Text Available Abstract Background There are detailed reviews about different recruitment strategies, but not with regard to differences between recruitment of hospital-based versus office-based physicians. Within this study, the two different recruitment schemes are compared. Advantages and disadvantages of different ways of recruitment in registry-based studies are discussed. Methods In a cross-sectional cancer-registry-based study, long-term melanoma patients were contacted by dermatologists rather than directly by the registry on the basis of the legal situation. Logistic regression models and generalized estimating equations were used to assess effects of various patient and physician characteristics on participation and data quality. Especially differences between hospital-based versus office-based dermatologists are evaluated. Results Seventy two out of 112 contacted dermatologists took part in the study (64.3%. The cooperation proportion was 52.2% (689 participants/1320 contacted patients. Participants and non-participants differed regarding age and sex, but not regarding other social demographic factors and cancer stage. We did not observe a difference in patient participation between hospital-based versus office-based dermatologists (OR 1.08 [CI 0.84–1.39]; p = 0.57. However, medical data provided by the cancer registry were better for participants registered and recruited by hospitals. Conclusions In cohort studies with epidemiological cancer registries, recruitment via physicians has potential disadvantages and is more complex. If this indirect way of contact is mandatory, we recommend recruitment procedures including hospital-based rather than office-based physicians. However, physician characteristics were not associated with outcome.

  14. Short-Term Load Forecasting Model Based on Quantum Elman Neural Networks

    Directory of Open Access Journals (Sweden)

    Zhisheng Zhang

    2016-01-01

    Full Text Available Short-term load forecasting model based on quantum Elman neural networks was constructed in this paper. The quantum computation and Elman feedback mechanism were integrated into quantum Elman neural networks. Quantum computation can effectively improve the approximation capability and the information processing ability of the neural networks. Quantum Elman neural networks have not only the feedforward connection but also the feedback connection. The feedback connection between the hidden nodes and the context nodes belongs to the state feedback in the internal system, which has formed specific dynamic memory performance. Phase space reconstruction theory is the theoretical basis of constructing the forecasting model. The training samples are formed by means of K-nearest neighbor approach. Through the example simulation, the testing results show that the model based on quantum Elman neural networks is better than the model based on the quantum feedforward neural network, the model based on the conventional Elman neural network, and the model based on the conventional feedforward neural network. So the proposed model can effectively improve the prediction accuracy. The research in the paper makes a theoretical foundation for the practical engineering application of the short-term load forecasting model based on quantum Elman neural networks.

  15. Reduced colon cancer incidence and mortality in postmenopausal women treated with an oral bisphosphonate-Danish National Register Based Cohort Study

    DEFF Research Database (Denmark)

    Pazianas, M; Abrahamsen, B; Eiken, Pia Agnete

    2012-01-01

    whether alendronate acts as chemopreventive. INTRODUCTION: When bisphosphonates are given by mouth, around 99% remains non-absorbed in the intestine. Based on their biochemical actions, we predicted that oral bisphosphonates might prevent colon cancers. METHODS: This is a Danish national register...... incidence and post-diagnosis survival in patients taking oral alendronate for osteoporosis. RESULTS: Cox proportional hazards analysis of death due to colon cancer showed lower risk in alendronate users, crude hazard ratio (HR) 0.69 (95% CI 0.59-0.81) with an adjusted HR of 0.62 (95% CI 0......In this Danish national register-based cohort study, we examined the effects of alendronate on the development of colon cancers and survival. The incidence of colon cancer and mortality rate, once colon cancer had been diagnosed, were lower in patients treated with alendronate, posing the question...

  16. Measurement-based local quantum filters and their ability to ...

    Indian Academy of Sciences (India)

    Debmalya Das

    2017-05-30

    May 30, 2017 ... Entanglement; local filters; quantum measurement. PACS No. 03.65 ... ties [4,5], it also plays a key role in quantum computing where it is ... Furthermore, we pro- vide an ..... Corresponding to each of these vectors, we can con-.

  17. Greenberger-Horne-Zeilinger states-based blind quantum computation with entanglement concentration.

    Science.gov (United States)

    Zhang, Xiaoqian; Weng, Jian; Lu, Wei; Li, Xiaochun; Luo, Weiqi; Tan, Xiaoqing

    2017-09-11

    In blind quantum computation (BQC) protocol, the quantum computability of servers are complicated and powerful, while the clients are not. It is still a challenge for clients to delegate quantum computation to servers and keep the clients' inputs, outputs and algorithms private. Unfortunately, quantum channel noise is unavoidable in the practical transmission. In this paper, a novel BQC protocol based on maximally entangled Greenberger-Horne-Zeilinger (GHZ) states is proposed which doesn't need a trusted center. The protocol includes a client and two servers, where the client only needs to own quantum channels with two servers who have full-advantage quantum computers. Two servers perform entanglement concentration used to remove the noise, where the success probability can almost reach 100% in theory. But they learn nothing in the process of concentration because of the no-signaling principle, so this BQC protocol is secure and feasible.

  18. Novel artefact removal algorithms for co-registered EEG/fMRI based on selective averaging and subtraction.

    Science.gov (United States)

    de Munck, Jan C; van Houdt, Petra J; Gonçalves, Sónia I; van Wegen, Erwin; Ossenblok, Pauly P W

    2013-01-01

    Co-registered EEG and functional MRI (EEG/fMRI) is a potential clinical tool for planning invasive EEG in patients with epilepsy. In addition, the analysis of EEG/fMRI data provides a fundamental insight into the precise physiological meaning of both fMRI and EEG data. Routine application of EEG/fMRI for localization of epileptic sources is hampered by large artefacts in the EEG, caused by switching of scanner gradients and heartbeat effects. Residuals of the ballistocardiogram (BCG) artefacts are similarly shaped as epileptic spikes, and may therefore cause false identification of spikes. In this study, new ideas and methods are presented to remove gradient artefacts and to reduce BCG artefacts of different shapes that mutually overlap in time. Gradient artefacts can be removed efficiently by subtracting an average artefact template when the EEG sampling frequency and EEG low-pass filtering are sufficient in relation to MR gradient switching (Gonçalves et al., 2007). When this is not the case, the gradient artefacts repeat themselves at time intervals that depend on the remainder between the fMRI repetition time and the closest multiple of the EEG acquisition time. These repetitions are deterministic, but difficult to predict due to the limited precision by which these timings are known. Therefore, we propose to estimate gradient artefact repetitions using a clustering algorithm, combined with selective averaging. Clustering of the gradient artefacts yields cleaner EEG for data recorded during scanning of a 3T scanner when using a sampling frequency of 2048 Hz. It even gives clean EEG when the EEG is sampled with only 256 Hz. Current BCG artefacts-reduction algorithms based on average template subtraction have the intrinsic limitation that they fail to deal properly with artefacts that overlap in time. To eliminate this constraint, the precise timings of artefact overlaps were modelled and represented in a sparse matrix. Next, the artefacts were disentangled with

  19. Cesarean Section and Rate of Subsequent Stillbirth, Miscarriage, and Ectopic Pregnancy: A Danish Register-Based Cohort Study

    Science.gov (United States)

    O'Neill, Sinéad M.; Agerbo, Esben; Kenny, Louise C.; Henriksen, Tine B.; Kearney, Patricia M.; Greene, Richard A.; Mortensen, Preben Bo; Khashan, Ali S.

    2014-01-01

    Background With cesarean section rates increasing worldwide, clarity regarding negative effects is essential. This study aimed to investigate the rate of subsequent stillbirth, miscarriage, and ectopic pregnancy following primary cesarean section, controlling for confounding by indication. Methods and Findings We performed a population-based cohort study using Danish national registry data linking various registers. The cohort included primiparous women with a live birth between January 1, 1982, and December 31, 2010 (n = 832,996), with follow-up until the next event (stillbirth, miscarriage, or ectopic pregnancy) or censoring by live birth, death, emigration, or study end. Cox regression models for all types of cesarean sections, sub-group analyses by type of cesarean, and competing risks analyses for the causes of stillbirth were performed. An increased rate of stillbirth (hazard ratio [HR] 1.14, 95% CI 1.01, 1.28) was found in women with primary cesarean section compared to spontaneous vaginal delivery, giving a theoretical absolute risk increase (ARI) of 0.03% for stillbirth, and a number needed to harm (NNH) of 3,333 women. Analyses by type of cesarean section showed similarly increased rates for emergency (HR 1.15, 95% CI 1.01, 1.31) and elective cesarean (HR 1.11, 95% CI 0.91, 1.35), although not statistically significant in the latter case. An increased rate of ectopic pregnancy was found among women with primary cesarean overall (HR 1.09, 95% CI 1.04, 1.15) and by type (emergency cesarean, HR 1.09, 95% CI 1.03, 1.15, and elective cesarean, HR 1.12, 95% CI 1.03, 1.21), yielding an ARI of 0.1% and a NNH of 1,000 women for ectopic pregnancy. No increased rate of miscarriage was found among women with primary cesarean, with maternally requested cesarean section associated with a decreased rate of miscarriage (HR 0.72, 95% CI 0.60, 0.85). Limitations include incomplete data on maternal body mass index, maternal smoking, fertility treatment, causes of

  20. A Coherence Preservation Control Strategy in Cavity QED Based on Classical Quantum Feedback

    Directory of Open Access Journals (Sweden)

    Ming Li

    2013-01-01

    Full Text Available For eliminating the unexpected decoherence effect in cavity quantum electrodynamics (cavity QED, the transfer function of Rabi oscillation is derived theoretically using optical Bloch equations. In particular, the decoherence in cavity QED from the atomic spontaneous emission is especially considered. A feedback control strategy is proposed to preserve the coherence through Rabi oscillation stabilization. In the scheme, a classical quantum feedback channel for the quantum information acquisition is constructed via the quantum tomography technology, and a compensation system based on the root locus theory is put forward to suppress the atomic spontaneous emission and the associated decoherence. The simulation results have proved its effectiveness and superiority for the coherence preservation.

  1. Strong coupling and polariton lasing in Te based microcavities embedding (Cd,Zn)Te quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Rousset, J.-G., E-mail: j-g.rousset@fuw.edu.pl; Piętka, B.; Król, M.; Mirek, R.; Lekenta, K.; Szczytko, J.; Borysiuk, J.; Suffczyński, J.; Kazimierczuk, T.; Goryca, M.; Smoleński, T.; Kossacki, P.; Nawrocki, M.; Pacuski, W. [Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, PL-02-093 Warszawa (Poland)

    2015-11-16

    We report on properties of an optical microcavity based on (Cd,Zn,Mg)Te layers and embedding (Cd,Zn)Te quantum wells. The key point of the structure design is the lattice matching of the whole structure to MgTe, which eliminates the internal strain and allows one to embed an arbitrary number of unstrained quantum wells in the microcavity. We evidence the strong light-matter coupling regime already for the structure containing a single quantum well. Embedding four unstrained quantum wells results in further enhancement of the exciton-photon coupling and the polariton lasing in the strong coupling regime.

  2. a national register-based follow-up study of 15-to 19-year-old Finnish delinquents referred for forensic psychiatric examination between 1980 and 2010

    OpenAIRE

    Lindberg, Nina; Miettunen, Jouko; Heiskala, Anni; Kaltiala-Heino, Riittakerttu

    2017-01-01

    Abstract Background: The mortality rate of young offenders is high. Furthermore, mortality in young offenders is associated with psychiatric and substance use disorders. The primary aim of this national register-based follow-up study was to investigate the mortality rate of Finnish delinquents who underwent a forensic psychiatric examination between 1980 and 2010. As delinquency is not a solid entity, we further aimed to compare the risk of premature death among different subgroups of the ...

  3. Trends in suicide risk associated with hospitalized psychiatric illness: a case-control study based on danish longitudinal registers

    DEFF Research Database (Denmark)

    Qin, Ping; Nordentoft, Merete; Hansen Høyer, Eyd

    2006-01-01

    longitudinal registers. Data were analyzed using conditional logistic regression. RESULTS: This study shows that the reduction in suicide rate is generally faster among individuals with a history of psychiatric admission than among individuals without such a history. However, this substantial reduction...... at the time of suicide or the index date, the reduction in suicide rate is relatively slower. Such trends hold for all diagnostic groups. Further analyses stratified by age indicate that the faster reduction in suicide rate associated with history of hospitalized psychiatric illness is more pronounced among...

  4. Tribological Properties of a Pennzane(Registered Trademark)-Based Liquid Lubricant (Disubstituted Alkylated Cyclopentane) for Low Temperature Space Applications

    Science.gov (United States)

    Venier, Clifford; Casserly, Edward W.; Jones, William R., Jr.; Marchetti, Mario; Jansen, Mark J.; Predmore, Roamer E.

    2002-01-01

    The tribological properties of a disubstituted alkylated cyclopentane, Pennzane (registered) Synthesized Hydrocarbon Fluid X-1000, are presented. This compound is a lower molecular weight version of the commonly used multiply alkylated cyclopentane, Pennzane X-2000, currently used in many space mechanisms. New, lower temperature applications will require liquid lubricants with lower viscosities and pour points and acceptable vapor pressures. Properties reported include: friction and wear studies and lubricated lifetime in vacuum; additionally, typical physical properties (i.e., viscosity-temperature, pour point, flash and fire point, specific gravity, refractive index, thermal properties, volatility and vapor pressure) are reported.

  5. Handheld Longwave Infrared Camera Based on Highly-Sensitive Quantum Well Infrared Photodetectors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a compact handheld longwave infrared camera based on quantum well infrared photodetector (QWIP) focal plane array (FPA) technology. Based on...

  6. Cascade quantum teleportation

    Institute of Scientific and Technical Information of China (English)

    ZHOU Nan-run; GONG Li-hua; LIU Ye

    2006-01-01

    In this letter a cascade quantum teleportation scheme is proposed. The proposed scheme needs less local quantum operations than those of quantum multi-teleportation. A quantum teleportation scheme based on entanglement swapping is presented and compared with the cascade quantum teleportation scheme. Those two schemes can effectively teleport quantum information and extend the distance of quantum communication.

  7. Routing protocol for wireless quantum multi-hop mesh backbone network based on partially entangled GHZ state

    Science.gov (United States)

    Xiong, Pei-Ying; Yu, Xu-Tao; Zhang, Zai-Chen; Zhan, Hai-Tao; Hua, Jing-Yu

    2017-08-01

    Quantum multi-hop teleportation is important in the field of quantum communication. In this study, we propose a quantum multi-hop communication model and a quantum routing protocol with multihop teleportation for wireless mesh backbone networks. Based on an analysis of quantum multi-hop protocols, a partially entangled Greenberger-Horne-Zeilinger (GHZ) state is selected as the quantum channel for the proposed protocol. Both quantum and classical wireless channels exist between two neighboring nodes along the route. With the proposed routing protocol, quantum information can be transmitted hop by hop from the source node to the destination node. Based on multi-hop teleportation based on the partially entangled GHZ state, a quantum route established with the minimum number of hops. The difference between our routing protocol and the classical one is that in the former, the processes used to find a quantum route and establish quantum channel entanglement occur simultaneously. The Bell state measurement results of each hop are piggybacked to quantum route finding information. This method reduces the total number of packets and the magnitude of air interface delay. The deduction of the establishment of a quantum channel between source and destination is also presented here. The final success probability of quantum multi-hop teleportation in wireless mesh backbone networks was simulated and analyzed. Our research shows that quantum multi-hop teleportation in wireless mesh backbone networks through a partially entangled GHZ state is feasible.

  8. Quantum Logic Network for Cloning a State Near a Given One Based on Cavity QED

    International Nuclear Information System (INIS)

    Da-Wei, Zhang; Xiao-Qiang, Shao; Ai-Dong, Zhu

    2008-01-01

    A quantum logic network is constructed to simulate a cloning machine which copies states near a given one. Meanwhile, a scheme for implementing this cloning network based on the technique of cavity quantum electrodynamics (QED) is presented. It is easy to implement this network of cloning machine in the framework of cavity QED and feasible in the experiment. (general)

  9. Proof of the insecurity of quantum secret sharing based on the Smolin bound entangled states

    International Nuclear Information System (INIS)

    Ya-Fei, Yu; Zhi-Ming, Zhang

    2009-01-01

    This paper reconsiders carefully the possibility of using the Smolin bound entangled states as the carrier for sharing quantum secret. It finds that the process of quantum secret sharing based on Smolin states has insecurity though the Smolin state was reported to violate maximally the two-setting Bell-inequality. The general proof is given. (general)

  10. Quantum dialogue using non-maximally entangled states based on entanglement swapping

    International Nuclear Information System (INIS)

    Xia Yan; Song Jie; Song Heshan

    2007-01-01

    We present a secure quantum dialogue protocol using non-maximally entangled two-particle states via entanglement swapping at first, and then discuss the requirements for a real quantum dialogue. Within the present version two authorized users can exchange their faithful secret messages securely and simultaneously based on the method of entanglement purification

  11. Fractures in Individuals With and Without a History of Infantile Autism. A Danish Register Study Based on Hospital Discharge Diagnoses

    DEFF Research Database (Denmark)

    Mouridsen, Svend-Erik; Rich, Bente; Isager, Torben

    2012-01-01

    observation time was 30.3 years (range 27.3-30.4 years), and mean age at follow-up was 42.7 years (range 27.3-57.3 years). Of the 118 individuals with IA, 14 (11.9%) were registered with at least one fracture diagnosis against 83 (24.7%) in the comparison group (p = 0.004; OR = 0.41; 95%CI 0......We compared the prevalence and types of fractures in a clinical sample of 118 individuals diagnosed as children with infantile autism (IA) with 336 matched controls from the general population. All participants were screened through the nationwide Danish National Hospital Register. The average.......22-0.76), but the nature of their fractures seems somewhat different. Epilepsy was a risk factor, but only in the comparison group. Our results lend no support to the notion that fracture is a common comorbid condition in a population of people diagnosed with IA as children....

  12. Next Generation Extended Lagrangian Quantum-based Molecular Dynamics

    Science.gov (United States)

    Negre, Christian

    2017-06-01

    A new framework for extended Lagrangian first-principles molecular dynamics simulations is presented, which overcomes shortcomings of regular, direct Born-Oppenheimer molecular dynamics, while maintaining important advantages of the unified extended Lagrangian formulation of density functional theory pioneered by Car and Parrinello three decades ago. The new framework allows, for the first time, energy conserving, linear-scaling Born-Oppenheimer molecular dynamics simulations, which is necessary to study larger and more realistic systems over longer simulation times than previously possible. Expensive, self-consinstent-field optimizations are avoided and normal integration time steps of regular, direct Born-Oppenheimer molecular dynamics can be used. Linear scaling electronic structure theory is presented using a graph-based approach that is ideal for parallel calculations on hybrid computer platforms. For the first time, quantum based Born-Oppenheimer molecular dynamics simulation is becoming a practically feasible approach in simulations of +100,000 atoms-representing a competitive alternative to classical polarizable force field methods. In collaboration with: Anders Niklasson, Los Alamos National Laboratory.

  13. A Generic Simulation Framework for Non-Entangled based Experimental Quantum Cryptography and Communication: Quantum Cryptography and Communication Simulator (QuCCs)

    Science.gov (United States)

    Buhari, Abudhahir; Zukarnain, Zuriati Ahmad; Khalid, Roszelinda; Zakir Dato', Wira Jaafar Ahmad

    2016-11-01

    The applications of quantum information science move towards bigger and better heights for the next generation technology. Especially, in the field of quantum cryptography and quantum computation, the world already witnessed various ground-breaking tangible product and promising results. Quantum cryptography is one of the mature field from quantum mechanics and already available in the markets. The current state of quantum cryptography is still under various researches in order to reach the heights of digital cryptography. The complexity of quantum cryptography is higher due to combination of hardware and software. The lack of effective simulation tool to design and analyze the quantum cryptography experiments delays the reaching distance of the success. In this paper, we propose a framework to achieve an effective non-entanglement based quantum cryptography simulation tool. We applied hybrid simulation technique i.e. discrete event, continuous event and system dynamics. We also highlight the limitations of a commercial photonic simulation tool based experiments. Finally, we discuss ideas for achieving one-stop simulation package for quantum based secure key distribution experiments. All the modules of simulation framework are viewed from the computer science perspective.

  14. Probability distributions for Markov chain based quantum walks

    Science.gov (United States)

    Balu, Radhakrishnan; Liu, Chaobin; Venegas-Andraca, Salvador E.

    2018-01-01

    We analyze the probability distributions of the quantum walks induced from Markov chains by Szegedy (2004). The first part of this paper is devoted to the quantum walks induced from finite state Markov chains. It is shown that the probability distribution on the states of the underlying Markov chain is always convergent in the Cesaro sense. In particular, we deduce that the limiting distribution is uniform if the transition matrix is symmetric. In the case of a non-symmetric Markov chain, we exemplify that the limiting distribution of the quantum walk is not necessarily identical with the stationary distribution of the underlying irreducible Markov chain. The Szegedy scheme can be extended to infinite state Markov chains (random walks). In the second part, we formulate the quantum walk induced from a lazy random walk on the line. We then obtain the weak limit of the quantum walk. It is noted that the current quantum walk appears to spread faster than its counterpart-quantum walk on the line driven by the Grover coin discussed in literature. The paper closes with an outlook on possible future directions.

  15. Association Between Prepartum Maternal Iron Deficiency and Offspring Risk of Schizophrenia: Population-Based Cohort Study With Linkage of Danish National Registers

    DEFF Research Database (Denmark)

    Sørensen, Holger J; Nielsen, Philip R; Pedersen, Carsten B

    2010-01-01

    Recent findings suggest that maternal iron deficiency may increase the risk of schizophrenia-spectrum disorder in offspring. We initiated this study to determine whether maternal prepartum anemia influences offspring risk of schizophrenia. We conducted a population-based study with individual...... a 1.60-fold (95% confidence interval = 1.16-2.15) increased risk of schizophrenia. Although the underlying mechanisms are unknown and independent replication is needed, our findings suggest that maternal iron deficiency increases offspring risk of schizophrenia....... record linkage of the Danish Civil Registration System, the Danish Psychiatric Central Register, and the Danish National Hospital Register. In a cohort of 1 115 752 Danish singleton births from 1978 to 1998, cohort members were considered as having a maternal history of anemia if the mother had received...

  16. Association Between Prepartum Maternal Iron Deficiency and Offspring Risk of Schizophrenia: Population-Based Cohort Study With Linkage of Danish National Registers

    DEFF Research Database (Denmark)

    Sørensen, Holger J; Nielsen, Philip R; Pedersen, Carsten B

    2011-01-01

    Recent findings suggest that maternal iron deficiency may increase the risk of schizophrenia-spectrum disorder in offspring. We initiated this study to determine whether maternal prepartum anemia influences offspring risk of schizophrenia. We conducted a population-based study with individual...... a 1.60-fold (95% confidence interval = 1.16-2.15) increased risk of schizophrenia. Although the underlying mechanisms are unknown and independent replication is needed, our findings suggest that maternal iron deficiency increases offspring risk of schizophrenia....... record linkage of the Danish Civil Registration System, the Danish Psychiatric Central Register, and the Danish National Hospital Register. In a cohort of 1 115 752 Danish singleton births from 1978 to 1998, cohort members were considered as having a maternal history of anemia if the mother had received...

  17. Silicon-based spin and charge quantum computation

    Directory of Open Access Journals (Sweden)

    Belita Koiller

    2005-06-01

    Full Text Available Silicon-based quantum-computer architectures have attracted attention because of their promise for scalability and their potential for synergetically utilizing the available resources associated with the existing Si technology infrastructure. Electronic and nuclear spins of shallow donors (e.g. phosphorus in Si are ideal candidates for qubits in such proposals due to the relatively long spin coherence times. For these spin qubits, donor electron charge manipulation by external gates is a key ingredient for control and read-out of single-qubit operations, while shallow donor exchange gates are frequently invoked to perform two-qubit operations. More recently, charge qubits based on tunnel coupling in P+2 substitutional molecular ions in Si have also been proposed. We discuss the feasibility of the building blocks involved in shallow donor quantum computation in silicon, taking into account the peculiarities of silicon electronic structure, in particular the six degenerate states at the conduction band edge. We show that quantum interference among these states does not significantly affect operations involving a single donor, but leads to fast oscillations in electron exchange coupling and on tunnel-coupling strength when the donor pair relative position is changed on a lattice-parameter scale. These studies illustrate the considerable potential as well as the tremendous challenges posed by donor spin and charge as candidates for qubits in silicon.Arquiteturas de computadores quânticos baseadas em silício vêm atraindo atenção devido às suas perspectivas de escalabilidade e utilização dos recursos já instalados associados à tecnologia do Si. Spins eletrônicos e nucleares de doadores rasos (por exemplo fósforo em Si são candidatos ideais para bits quânticos (qubits nestas propostas, devido aos tempos de coerência relativamente longos dos spins em matrizes de Si. Para estes qubits de spin, a manipulação da carga do elétron do doador

  18. Black hole based quantum computing in labs and in the sky

    Energy Technology Data Exchange (ETDEWEB)

    Dvali, Gia [Arnold Sommerfeld Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen (Germany); Max-Planck-Institut fuer Physik, Muenchen (Germany); Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY (United States); Panchenko, Mischa [Arnold Sommerfeld Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen (Germany)

    2016-08-15

    Analyzing some well established facts, we give a model-independent parameterization of black hole quantum computing in terms of a set of macro and micro quantities and their relations. These include the relations between the extraordinarily-small energy gap of black hole qubits and important time-scales of information-processing, such as, scrambling time and Page's time. We then show, confirming and extending previous results, that other systems of nature with identical quantum informatics features are attractive Bose-Einstein systems at the critical point of quantum phase transition. Here we establish a complete isomorphy between the quantum computational properties of these two systems. In particular, we show that the quantum hair of a critical condensate is strikingly similar to the quantum hair of a black hole. Irrespectively whether one takes the similarity between the two systems as a remarkable coincidence or as a sign of a deeper underlying connection, the following is evident. Black holes are not unique in their way of quantum information processing and we can manufacture black hole based quantum computers in labs by taking advantage of quantum criticality. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Trajectory-based understanding of the quantum-classical transition for barrier scattering

    Science.gov (United States)

    Chou, Chia-Chun

    2018-06-01

    The quantum-classical transition of wave packet barrier scattering is investigated using a hydrodynamic description in the framework of a nonlinear Schrödinger equation. The nonlinear equation provides a continuous description for the quantum-classical transition of physical systems by introducing a degree of quantumness. Based on the transition equation, the transition trajectory formalism is developed to establish the connection between classical and quantum trajectories. The quantum-classical transition is then analyzed for the scattering of a Gaussian wave packet from an Eckart barrier and the decay of a metastable state. Computational results for the evolution of the wave packet and the transmission probabilities indicate that classical results are recovered when the degree of quantumness tends to zero. Classical trajectories are in excellent agreement with the transition trajectories in the classical limit, except in some regions where transition trajectories cannot cross because of the single-valuedness of the transition wave function. As the computational results demonstrate, the process that the Planck constant tends to zero is equivalent to the gradual removal of quantum effects originating from the quantum potential. This study provides an insightful trajectory interpretation for the quantum-classical transition of wave packet barrier scattering.

  20. Black hole based quantum computing in labs and in the sky

    International Nuclear Information System (INIS)

    Dvali, Gia; Panchenko, Mischa

    2016-01-01

    Analyzing some well established facts, we give a model-independent parameterization of black hole quantum computing in terms of a set of macro and micro quantities and their relations. These include the relations between the extraordinarily-small energy gap of black hole qubits and important time-scales of information-processing, such as, scrambling time and Page's time. We then show, confirming and extending previous results, that other systems of nature with identical quantum informatics features are attractive Bose-Einstein systems at the critical point of quantum phase transition. Here we establish a complete isomorphy between the quantum computational properties of these two systems. In particular, we show that the quantum hair of a critical condensate is strikingly similar to the quantum hair of a black hole. Irrespectively whether one takes the similarity between the two systems as a remarkable coincidence or as a sign of a deeper underlying connection, the following is evident. Black holes are not unique in their way of quantum information processing and we can manufacture black hole based quantum computers in labs by taking advantage of quantum criticality. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Fidelity-Based Ant Colony Algorithm with Q-learning of Quantum System

    Science.gov (United States)

    Liao, Qin; Guo, Ying; Tu, Yifeng; Zhang, Hang

    2018-03-01

    Quantum ant colony algorithm (ACA) has potential applications in quantum information processing, such as solutions of traveling salesman problem, zero-one knapsack problem, robot route planning problem, and so on. To shorten the search time of the ACA, we suggest the fidelity-based ant colony algorithm (FACA) for the control of quantum system. Motivated by structure of the Q-learning algorithm, we demonstrate the combination of a FACA with the Q-learning algorithm and suggest the design of a fidelity-based ant colony algorithm with the Q-learning to improve the performance of the FACA in a spin-1/2 quantum system. The numeric simulation results show that the FACA with the Q-learning can efficiently avoid trapping into local optimal policies and increase the speed of convergence process of quantum system.

  2. Insecurity of position-based quantum-cryptography protocols against entanglement attacks

    International Nuclear Information System (INIS)

    Lau, Hoi-Kwan; Lo, Hoi-Kwong

    2011-01-01

    Recently, position-based quantum cryptography has been claimed to be unconditionally secure. On the contrary, here we show that the existing proposals for position-based quantum cryptography are, in fact, insecure if entanglement is shared among two adversaries. Specifically, we demonstrate how the adversaries can incorporate ideas of quantum teleportation and quantum secret sharing to compromise the security with certainty. The common flaw to all current protocols is that the Pauli operators always map a codeword to a codeword (up to an irrelevant overall phase). We propose a modified scheme lacking this property in which the same cheating strategy used to undermine the previous protocols can succeed with a rate of at most 85%. We prove the modified protocol is secure when the shared quantum resource between the adversaries is a two- or three-level system.

  3. A survey-based exploration of the impact of dyslexia on career progression of UK registered nurses.

    Science.gov (United States)

    Morris, David; Turnbull, Patricia

    2007-01-01

    To explore the effects of dyslexia on the practice and career progression of UK registered nurses (RN). Literature suggests dyslexia can have a negative impact in the workplace and may pose particular difficulties for nurses, where accuracy in information processing activities is essential for practice. A questionnaire was used to survey RNs with dyslexia (n = 116) and results analysed using content analysis. Dyslexia provided a challenge to the everyday work of RNs, which was often met successfully using a range of individualized strategies. Career progression was achievable but compared with peers, was perceived to take longer. Disclosure of dyslexia to work-colleagues was selective and dependent on the perceived benefits. Informal support mechanisms were commonly utilized with formal management support less well defined. Dyslexia appears to have a negative impact on working practices and career progression, but remains a poorly understood and often hidden disability.

  4. Perinatal and maternal complications related to postterm delivery: A national register-based study, 1978-1993

    DEFF Research Database (Denmark)

    Olesen, Annette Wind; Westergaard, Jes G.; Olsen, Jørn

    2003-01-01

    OBJECTIVE: This study was undertaken to estimate the risk of fetal and maternal complications associated with postterm delivery in Denmark. STUDY DESIGN: A cross-sectional study that used records from the Danish Medical Birth Registry from 1978 to 1993 was performed. All women with registered...... to analyze data. RESULTS: The risk of perinatal and obstetric complications was high in postterm delivery compared with term delivery (adjusted odds ratios between 1.2 and 3.1). The risk of perinatal death was 1.33 (1.05-1.68). CONCLUSION: Postterm delivery was associated with significantly increased risks...... of perinatal and maternal complications in Denmark in the period from 1978 to 1993....

  5. Quantum Distinction: Quantum Distinctiones!

    OpenAIRE

    Zeps, Dainis

    2009-01-01

    10 pages; How many distinctions, in Latin, quantum distinctiones. We suggest approach of anthropic principle based on anthropic reference system which should be applied equally both in theoretical physics and in mathematics. We come to principle that within reference system of life subject of mathematics (that of thinking) should be equated with subject of physics (that of nature). For this reason we enter notions of series of distinctions, quantum distinction, and argue that quantum distinct...

  6. Association between alcohol, cannabis, and other illicit substance abuse and risk of developing schizophrenia: a nationwide population based register study.

    Science.gov (United States)

    Nielsen, S M; Toftdahl, N G; Nordentoft, M; Hjorthøj, C

    2017-07-01

    Several studies have examined whether use of substances can cause schizophrenia. However, due to methodological limitations in the existing literature (e.g. selection bias and lack of adjustment of co-abuse) uncertainties still remain. We aimed to investigate whether substance abuse increases the risk of developing schizophrenia, addressing some of these limitations. The longitudinal, nationwide Danish registers were linked to establish a cohort of 3 133 968 individuals (105 178 673 person-years at risk), identifying 204 505 individuals diagnosed with substance abuse and 21 305 diagnosed with schizophrenia. Information regarding substance abuse was extracted from several registers and did not include psychotic symptoms caused by substance abuse in the definition. This resulted in a large, generalizable sample of exposed individuals. The data was analysed using Cox regression analyses, and adjusted for calendar year, gender, urbanicity, co-abuse, other psychiatric diagnosis, parental substance abuse, psychiatric history, immigration and socioeconomic status. A diagnosis of substance abuse increased the overall risk of developing schizophrenia [hazard ratio (HR) 6.04, 95% confidence interval (CI) 5.84-6.26]. Cannabis (HR 5.20, 95% CI 4.86-5.57) and alcohol (HR 3.38, 95% CI 3.24-3.53) presented the strongest associations. Abuse of hallucinogens (HR 1.86, 95% CI 1.43-2.41), sedatives (HR 1.68, 95% CI 1.49-1.90), and other substances (HR 2.85, 95% CI 2.58-3.15) also increased the risk significantly. The risk was found to be significant even 10-15 years subsequent to a diagnosis of substance abuse. Our results illustrate robust associations between almost any type of substance abuse and an increased risk of developing schizophrenia later in life.

  7. Modulatable optical radiators and metasurfaces based on quantum nanoantennas

    KAUST Repository

    Chen, Pai-Yen; Farhat, Mohamed

    2015-01-01

    We investigate the tunable and switchable optical radiators and metamaterials formed by metallic nanodipole antennas with submicroscopic gaps (1.2 nm), of which linear and third-order nonlinear quantum conductivities are observed due to the photon-assisted tunneling effect. The quantum conductivities induced at the nanogap are relevant to power dissipations, which can be enhanced by the strongly localized optical fields associated with the plasmonic resonance. We demonstrate that the scattering property of an individual quantum nanoantenna and the transparency of a metamasurface constituted of it can be tuned by electrostatically controlling the linear conductivity (electronic tuning) or by adjusting the irradiation intensity that varies the nonlinear quantum conductivity (all-optical tuning).

  8. Modulatable optical radiators and metasurfaces based on quantum nanoantennas

    KAUST Repository

    Chen, Pai-Yen

    2015-01-20

    We investigate the tunable and switchable optical radiators and metamaterials formed by metallic nanodipole antennas with submicroscopic gaps (1.2 nm), of which linear and third-order nonlinear quantum conductivities are observed due to the photon-assisted tunneling effect. The quantum conductivities induced at the nanogap are relevant to power dissipations, which can be enhanced by the strongly localized optical fields associated with the plasmonic resonance. We demonstrate that the scattering property of an individual quantum nanoantenna and the transparency of a metamasurface constituted of it can be tuned by electrostatically controlling the linear conductivity (electronic tuning) or by adjusting the irradiation intensity that varies the nonlinear quantum conductivity (all-optical tuning).

  9. Enhanced Materials Based on Submonolayer Type-II Quantum Dots

    Energy Technology Data Exchange (ETDEWEB)

    Tamargo, Maria C [City College of New York, NY (United States); Kuskovsky, Igor L. [City Univ. (CUNY), NY (United States) Queens College; Meriles, Carlos [City College of New York, NY (United States); Noyan, Ismail C. [Columbia Univ., New York, NY (United States)

    2017-04-15

    We have investigated a nanostructured material known as sub-monolayer type-II QDs, made from wide bandgap II-VI semiconductors. Our goal is to understand and exploit their tunable optical and electrical properties by taking advantage of the type-II band alignment and quantum confinement effects. Type-II ZnTe quantum dots (QDs) in a ZnSe host are particularly interesting because of their relatively large valence band and conduction band offsets. In the current award we have developed new materials based on sub-monolayer type-II QDs that may be advantageous for photovoltaic and spintronics applications. We have also expanded the structural characterization of these materials by refining the X-ray diffraction methodologies needed to investigate them. In particular, we have 1) demonstrated ZnCdTe/ZnCdSe type-II QDs materials that have ideal properties for the development of novel high efficiency “intermediate band solar cells”, 2) we developed a comprehensive approach to describe and model the growth of these ultra-small type-II QDs, 3) analysis of the evolution of the photoluminescence (PL) emission, combined with other characterization probes allowed us to predict the size and density of the QDs as a function of the growth conditions, 4) we developed and implemented novel sophisticated X-ray diffraction techniques from which accurate size and shape of the buried type-II QDs could be extracted, 5) a correlation of the shape anisotropy with polarization dependent PL was observed, confirming the QDs detailed shape and providing insight about the effects of this shape anisotropy on the physical properties of the type-II QD systems, and 6) a detailed “time-resolved Kerr rotation” investigation has led to the demonstration of enhanced electron spin lifetimes for the samples with large densities of type-II QDs and an understanding of the interplay between the QDs and Te-isoelectroic centers, a defect that forms in the spacer layers that separate the QDs.

  10. Semi-quantum Dialogue Based on Single Photons

    Science.gov (United States)

    Ye, Tian-Yu; Ye, Chong-Qiang

    2018-02-01

    In this paper, we propose two semi-quantum dialogue (SQD) protocols by using single photons as the quantum carriers, where one requires the classical party to possess the measurement capability and the other does not have this requirement. The security toward active attacks from an outside Eve in the first SQD protocol is guaranteed by the complete robustness of present semi-quantum key distribution (SQKD) protocols, the classical one-time pad encryption, the classical party's randomization operation and the decoy photon technology. The information leakage problem of the first SQD protocol is overcome by the classical party' classical basis measurements on the single photons carrying messages which makes him share their initial states with the quantum party. The security toward active attacks from Eve in the second SQD protocol is guaranteed by the classical party's randomization operation, the complete robustness of present SQKD protocol and the classical one-time pad encryption. The information leakage problem of the second SQD protocol is overcome by the quantum party' classical basis measurements on each two adjacent single photons carrying messages which makes her share their initial states with the classical party. Compared with the traditional information leakage resistant QD protocols, the advantage of the proposed SQD protocols lies in that they only require one party to have quantum capabilities. Compared with the existing SQD protocol, the advantage of the proposed SQD protocols lies in that they only employ single photons rather than two-photon entangled states as the quantum carriers. The proposed SQD protocols can be implemented with present quantum technologies.

  11. Quantum dot-based microfluidic biosensor for cancer detection

    Energy Technology Data Exchange (ETDEWEB)

    Ghrera, Aditya Sharma [Biomedical Instrumentation Section, CSIR-National Physical Laboratory, New Delhi-110012 (India); School of Engineering and Technology, ITM University, Gurgaon-122017 (India); Pandey, Chandra Mouli; Ali, Md. Azahar [Biomedical Instrumentation Section, CSIR-National Physical Laboratory, New Delhi-110012 (India); Malhotra, Bansi Dhar, E-mail: bansi.malhotra@gmail.com [Department of Biotechnology, Delhi Technological University, Delhi-110042 (India)

    2015-05-11

    We report results of the studies relating to fabrication of an impedimetric microfluidic–based nucleic acid sensor for quantification of DNA sequences specific to chronic myelogenous leukemia (CML). The sensor chip is prepared by patterning an indium–tin–oxide (ITO) coated glass substrate via wet chemical etching method followed by sealing with polydimethylsiloxane (PDMS) microchannel for fluid control. The fabricated microfluidic chip comprising of a patterned ITO substrate is modified by depositing cadmium selenide quantum dots (QCdSe) via Langmuir–Blodgett technique. Further, the QCdSe surface has been functionalized with specific DNA probe for CML detection. The probe DNA functionalized QCdSe integrated miniaturized system has been used to monitor target complementary DNA concentration by measuring the interfacial charge transfer resistance via hybridization. The presence of complementary DNA in buffer solution significantly results in decreased electro-conductivity of the interface due to presence of a charge barrier for transport of the redox probe ions. The microfluidic DNA biosensor exhibits improved linearity in the concentration range of 10{sup −15} M to 10{sup −11} M.

  12. Quantum dot-based microfluidic biosensor for cancer detection

    Science.gov (United States)

    Ghrera, Aditya Sharma; Pandey, Chandra Mouli; Ali, Md. Azahar; Malhotra, Bansi Dhar

    2015-05-01

    We report results of the studies relating to fabrication of an impedimetric microfluidic-based nucleic acid sensor for quantification of DNA sequences specific to chronic myelogenous leukemia (CML). The sensor chip is prepared by patterning an indium-tin-oxide (ITO) coated glass substrate via wet chemical etching method followed by sealing with polydimethylsiloxane (PDMS) microchannel for fluid control. The fabricated microfluidic chip comprising of a patterned ITO substrate is modified by depositing cadmium selenide quantum dots (QCdSe) via Langmuir-Blodgett technique. Further, the QCdSe surface has been functionalized with specific DNA probe for CML detection. The probe DNA functionalized QCdSe integrated miniaturized system has been used to monitor target complementary DNA concentration by measuring the interfacial charge transfer resistance via hybridization. The presence of complementary DNA in buffer solution significantly results in decreased electro-conductivity of the interface due to presence of a charge barrier for transport of the redox probe ions. The microfluidic DNA biosensor exhibits improved linearity in the concentration range of 10-15 M to 10-11 M.

  13. Crystal density predictions for nitramines based on quantum chemistry

    International Nuclear Information System (INIS)

    Qiu Ling; Xiao Heming; Gong Xuedong; Ju Xuehai; Zhu Weihua

    2007-01-01

    An efficient and convenient method for predicting the crystalline densities of energetic materials was established based on the quantum chemical computations. Density functional theory (DFT) with four different basis sets (6-31G**, 6-311G**, 6-31+G**, and 6-311++G**) and various semiempirical molecular orbital (MO) methods have been employed to predict the molecular volumes and densities of a series of energetic nitramines including acyclic, monocyclic, and polycyclic/cage molecules. The relationships between the calculated values and experimental data were discussed in detail, and linear correlations were suggested and compared at different levels. The calculation shows that if the selected basis set is larger, it will expend more CPU (central processing unit) time, larger molecular volume and smaller density will be obtained. And the densities predicted by the semiempirical MO methods are all systematically larger than the experimental data. In comparison with other methods, B3LYP/6-31G** is most accurate and economical to predict the solid-state densities of energetic nitramines. This may be instructive to the molecular designing and screening novel HEDMs

  14. Biomedical applications of glyconanoparticles based on quantum dots.

    Science.gov (United States)

    Cunha, C R A; Oliveira, A D P R; Firmino, T V C; Tenório, D P L A; Pereira, G; Carvalho, L B; Santos, B S; Correia, M T S; Fontes, A

    2018-03-01

    Quantum dots (QDs) are outstanding nanomaterials of great interest to life sciences. Their conjugation versatility added to unique optical properties, highlight these nanocrystals as very promising fluorescent probes. Among uncountable new nanosystems, in the last years, QDs conjugated to glycans or lectins have aroused a growing attention and their application as a tool to study biological and functional properties has increased. This review describes the strategies, reported in the literature, to conjugate QDs to lectins or carbohydrates, providing valuable information for the elaboration, improvement, and application of these nanoconjugates. It also presents the main applications of these nanosystems in glycobiology, such as their potential to study microorganisms, the development of diseases such as cancer, as well as to develop biosensors. The development of glyconanoparticles based on QDs emerged in the last decade. Many works reporting the conjugation of QDs with carbohydrates and lectins have been published, using different strategies and reagents. These bioconjugates enabled studies that are very sensitive and specific, with potential to detect and elucidate the glycocode expressed in various normal or pathologic conditions. Produce a quick reference source over the main advances reached in the glyconanotechnology using QDs as fluorescent probes. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Quantum dot-based microfluidic biosensor for cancer detection

    International Nuclear Information System (INIS)

    Ghrera, Aditya Sharma; Pandey, Chandra Mouli; Ali, Md. Azahar; Malhotra, Bansi Dhar

    2015-01-01

    We report results of the studies relating to fabrication of an impedimetric microfluidic–based nucleic acid sensor for quantification of DNA sequences specific to chronic myelogenous leukemia (CML). The sensor chip is prepared by patterning an indium–tin–oxide (ITO) coated glass substrate via wet chemical etching method followed by sealing with polydimethylsiloxane (PDMS) microchannel for fluid control. The fabricated microfluidic chip comprising of a patterned ITO substrate is modified by depositing cadmium selenide quantum dots (QCdSe) via Langmuir–Blodgett technique. Further, the QCdSe surface has been functionalized with specific DNA probe for CML detection. The probe DNA functionalized QCdSe integrated miniaturized system has been used to monitor target complementary DNA concentration by measuring the interfacial charge transfer resistance via hybridization. The presence of complementary DNA in buffer solution significantly results in decreased electro-conductivity of the interface due to presence of a charge barrier for transport of the redox probe ions. The microfluidic DNA biosensor exhibits improved linearity in the concentration range of 10 −15 M to 10 −11 M

  16. Ancilla-driven quantum computation for qudits and continuous variables

    Science.gov (United States)

    Proctor, Timothy; Giulian, Melissa; Korolkova, Natalia; Andersson, Erika; Kendon, Viv

    2017-05-01

    Although qubits are the leading candidate for the basic elements in a quantum computer, there are also a range of reasons to consider using higher-dimensional qudits or quantum continuous variables (QCVs). In this paper, we use a general "quantum variable" formalism to propose a method of quantum computation in which ancillas are used to mediate gates on a well-isolated "quantum memory" register and which may be applied to the setting of qubits, qudits (for d >2 ), or QCVs. More specifically, we present a model in which universal quantum computation may be implemented on a register using only repeated applications of a single fixed two-body ancilla-register interaction gate, ancillas prepared in a single state, and local measurements of these ancillas. In order to maintain determinism in the computation, adaptive measurements via a classical feed forward of measurement outcomes are used, with the method similar to that in measurement-based quantum computation (MBQC). We show that our model has the same hybrid quantum-classical processing advantages as MBQC, including the power to implement any Clifford circuit in essentially one layer of quantum computation. In some physical settings, high-quality measurements of the ancillas may be highly challenging or not possible, and hence we also present a globally unitary model which replaces the need for measurements of the ancillas with the requirement for ancillas to be prepared in states from a fixed orthonormal basis. Finally, we discuss settings in which these models may be of practical interest.

  17. Single-hidden-layer feed-forward quantum neural network based on Grover learning.

    Science.gov (United States)

    Liu, Cheng-Yi; Chen, Chein; Chang, Ching-Ter; Shih, Lun-Min

    2013-09-01

    In this paper, a novel single-hidden-layer feed-forward quantum neural network model is proposed based on some concepts and principles in the quantum theory. By combining the quantum mechanism with the feed-forward neural network, we defined quantum hidden neurons and connected quantum weights, and used them as the fundamental information processing unit in a single-hidden-layer feed-forward neural network. The quantum neurons make a wide range of nonlinear functions serve as the activation functions in the hidden layer of the network, and the Grover searching algorithm outstands the optimal parameter setting iteratively and thus makes very efficient neural network learning possible. The quantum neuron and weights, along with a Grover searching algorithm based learning, result in a novel and efficient neural network characteristic of reduced network, high efficient training and prospect application in future. Some simulations are taken to investigate the performance of the proposed quantum network and the result show that it can achieve accurate learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Effect of sulfonated carbon nanofiber-supported Pt on performance of Nafion {sup registered} -based self-humidifying composite membrane for proton exchange membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Hung, T.F. [Department of Chemistry and Center for Nanotechnology, Chung Yuan Christian University, 200 Chung Pei Rd., Chung-Li, 32023 (China); Department of Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 10617 (China); Liao, S.H.; Li, C.Y.; Chen-Yang, Y.W. [Department of Chemistry and Center for Nanotechnology, Chung Yuan Christian University, 200 Chung Pei Rd., Chung-Li, 32023 (China)

    2011-01-01

    In the present study, the Nafion {sup registered} -based self-humidifying composite membrane (N-SHCM) with sulfonated carbon nanofiber-supported Pt (s-Pt/CNF) catalyst, N-s-Pt/CNF, is successfully prepared using the solution-casting method. The scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) images of N-s-Pt/CNF indicate that s-Pt/CNF is well dispersed in the Nafion {sup registered} matrix due to the good compatibility between Nafion {sup registered} and s-Pt/CNF. Compared with those of the non-sulfonated Pt/CNF-containing N-SHCM, N-Pt/CNF, the properties of N-s-Pt/CNF, including electronic resistivity, ion-exchange capacity (IEC), water uptake, dimensional stability, and catalytic activity, significantly increase. The maximum power density of the proton exchange membrane fuel cell (PEMFC) fabricated with N-s-Pt/CNF operated at 50 C under dry H{sub 2}/O{sub 2} condition is about 921 mW cm{sup -2}, which is approximately 34% higher than that with N-Pt/CNF. (author)

  19. Spontaneous abortions and malformations in the offspring of nurses exposed to anaesthetic gases, cytostatic drugs, and other potential hazards in hospitals, based on registered information of outcome

    Energy Technology Data Exchange (ETDEWEB)

    Hemminki, K; Kyyroenen, P L; Lindbohm, M L

    1985-06-01

    Nurses working in selected departments of general hospitals in Finland were collected from a central register on health personnel in Finland. Using the Hospital Discharge Register and the Register of Congenital Malformations, case nurses were selected who had had a spontaneous abortion (N = 217) or a malformed child (N = 46) between the years 1973 and 1979. Controls consisted of three nurses who had had a normal birth; the control nurses were matched for age and hospital of employment. Information on exposure in the first trimester of pregnancy was sought through the head nurses of the hospitals. No significant increase in risk of spontaneous abortion or of malformation was observed after exposure to anaesthetic gases (odds ratio for spontaneous abortion 1.2), sterilizing gases and soaps, or x-rays. Handling of cytostatic drugs did not affect the frequency of spontaneous abortion but was associated with malformations in the offspring. The odds ratio, based on eight cases, was 4.7 (p = 0.02) when the logistic model was adopted. The results suggest that the exposures investigated, other than cytostatic drugs, do not cause a strong reproductive risk. Further studies are needed, particularly on cytostatic drugs.

  20. The Fraunhofer Quantum Computing Portal - www.qc.fraunhofer.de: A web-based simulator of quantum computing processes

    OpenAIRE

    Rosé, H.; Asselmeyer-Maluga, T.; Kolbe, M.; Niehörster, F.; Schramm, A.

    2004-01-01

    Fraunhofer FIRST develops a computing service and collaborative workspace providing a convenient tool for simulation and investigation of quantum algorithms. To broaden the twenty qubit limit of workstation-based simulations to the next qubit decade we provide a dedicated high memorized Linux cluster with fast Myrinet interconnection network together with a adapted parallel simulator engine. This simulation service supplemented by a collaborative workspace is usable everywhere via web interfa...

  1. Arthroplasty register for Germany

    Directory of Open Access Journals (Sweden)

    Hagen, Anja

    2009-10-01

    Full Text Available Scientific background: The annual number of joint replacement operations in Germany is high. The introduction of an arthroplasty register promises an important contribution to the improvement of the quality of patient’s care. Research questions: The presented report addresses the questions on organization and functioning, benefits and cost-benefits as well as on legal, ethical and social aspects of the arthroplasty registers. Methods: A systematic literature search was conducted in September 2008 in the medical databases MEDLINE, EMBASE etc. and was complemented with a hand search. Documents describing arthroplasty registers and/or their relevance as well as papers on legal, ethical and social aspects of such registers were included in the evaluation. The most important information was extracted and analysed. Results: Data concerning 30 arthroplasty registers in 19 countries as well as one international arthroplasty register were identified. Most of the arthroplasty registers are maintained by national orthopedic societies, others by health authorities or by their cooperation. Mostly, registries are financially supported by governments and rarely by other sources.The participation of the orthopedists in the data collection process of the arthroplasty registry is voluntary in most countries. The consent of the patients is usually required. The unique patient identification is ensured in nearly all registers.Each data set consists of patient and clinic identification numbers, data on diagnosis, the performed intervention, the operation date and implanted prostheses. The use of clinical scores, patient-reported questionnaires and radiological documentation is rare. Methods for data documentation and transfer are paper form, electronic entry as well as scanning of the data using bar codes. The data are mostly being checked for their completeness and validity. Most registers offer results of the data evaluation to the treating orthopedists and

  2. Short- and long-term risks of cardiovascular disease following radiotherapy in rectal cancer in four randomized controlled trials and a population-based register.

    Science.gov (United States)

    Chen, Lingjing; Eloranta, Sandra; Martling, Anna; Glimelius, Ingrid; Neovius, Martin; Glimelius, Bengt; Smedby, Karin E

    2018-03-01

    A population-based cohort and four randomized trials enriched with long-term register data were used to clarify if radiotherapy in combination with rectal cancer surgery is associated with increased risks of cardiovascular disease (CVD). We identified 14,901 rectal cancer patients diagnosed 1995-2009 in Swedish nationwide registers, of whom 9227 were treated with preoperative radiotherapy. Also, we investigated 2675 patients with rectal cancer previously randomized to preoperative radiotherapy or not followed by surgery in trials conducted 1980-1999. Risks of CVD overall and subtypes were estimated based on prospectively recorded hospital visits during relapse-free follow-up using multivariable Cox regression. Maximum follow-up was 18 and 33 years in the register and trials, respectively. We found no association between preoperative radiotherapy and overall CVD risk in the register (Incidence Rate Ratio, IRR = 0.99, 95% confidence interval (CI) 0.92-1.06) or in the pooled trials (IRR = 1.07, 95% CI 0.93-1.24). We noted an increased risk of venous thromboembolism among irradiated patients in both cohorts (IRR register  = 1.41, 95% CI 1.15-2.72; IRR trials  = 1.41, 95% CI 0.97-2.04), that remained during the first 6 months following surgery among patients treated 2006-2009, after the introduction of antithrombotic treatment (IRR 6 months  = 2.30, 95% CI 1.01-5.21). However, the absolute rate difference of venous thromboembolism attributed to RT was low (10 cases per 1000 patients and year). Preoperative radiotherapy did not affect rectal cancer patients' risk of CVD overall. Although an excess risk of short-term venous thromboembolism was noted, the small increase in absolute numbers does not call for general changes in routine prophylactic treatment, but might do so for patients already at high risk of venous thromboembolism. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Two-party quantum key agreement based on four-particle GHZ states

    Science.gov (United States)

    He, Ye-Feng; Ma, Wen-Ping

    2016-04-01

    Based on four-particle GHZ states, the double CNOT operation and the delayed measurement technique, a two-party quantum key agreement (QKA) protocols is proposed. The double CNOT operation makes each four-particle GHZ state collapse into two independent quantum states without any entanglement. Furthermore, one party can directly know the two quantum states and the other party can be aware of the two quantum states by using the corresponding measurement. According to the initial states of the two quantum states, two parties can extract the secret keys of each other by using the publicly announced value or by performing the delayed measurement, respectively. Then the protocol achieves the fair establishment of a shared key. The security analysis shows that the new protocol can resist against participant attacks, the Trojan horse attacks and other outsider attacks. Furthermore, the new protocol also has no information leakage problem and has high qubit efficiency.

  4. Quantum image encryption based on generalized affine transform and logistic map

    Science.gov (United States)

    Liang, Hao-Ran; Tao, Xiang-Yang; Zhou, Nan-Run

    2016-07-01

    Quantum circuits of the generalized affine transform are devised based on the novel enhanced quantum representation of digital images. A novel quantum image encryption algorithm combining the generalized affine transform with logistic map is suggested. The gray-level information of the quantum image is encrypted by the XOR operation with a key generator controlled by the logistic map, while the position information of the quantum image is encoded by the generalized affine transform. The encryption keys include the independent control parameters used in the generalized affine transform and the logistic map. Thus, the key space is large enough to frustrate the possible brute-force attack. Numerical simulations and analyses indicate that the proposed algorithm is realizable, robust and has a better performance than its classical counterpart in terms of computational complexity.

  5. Thermodynamic stability criteria for a quantum memory based on stabilizer and subsystem codes

    International Nuclear Information System (INIS)

    Chesi, Stefano; Loss, Daniel; Bravyi, Sergey; Terhal, Barbara M

    2010-01-01

    We discuss several thermodynamic criteria that have been introduced to characterize the thermal stability of a self-correcting quantum memory. We first examine the use of symmetry-breaking fields in analyzing the properties of self-correcting quantum memories in the thermodynamic limit; we show that the thermal expectation values of all logical operators vanish for any stabilizer and any subsystem code in any spatial dimension. On the positive side, we generalize the results of Alicki et al to obtain a general upper bound on the relaxation rate of a quantum memory at nonzero temperature, assuming that the quantum memory interacts via a Markovian master equation with a thermal bath. This upper bound is applicable to quantum memories based on either stabilizer or subsystem codes.

  6. Spectrally-Tunable Infrared Camera Based on Highly-Sensitive Quantum Well Infrared Photodetectors, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a SPECTRALLY-TUNABLE INFRARED CAMERA based on quantum well infrared photodetector (QWIP) focal plane array (FPA) technology. This will build on...

  7. The Danish Pathology Register

    DEFF Research Database (Denmark)

    Bjerregaard, Beth; Larsen, Ole B

    2011-01-01

    The National Board of Health, Denmark in 1997 published guidelines for reporting of pathology data and the Danish Pathology Register (DPR) was established.......The National Board of Health, Denmark in 1997 published guidelines for reporting of pathology data and the Danish Pathology Register (DPR) was established....

  8. Registered Nurse (Associate Degree).

    Science.gov (United States)

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of registered nurse (with an associate degree), lists technical competencies and competency builders for 19 units pertinent to the health technologies cluster in general and 5 units specific to the occupation of registered nurse. The following…

  9. The Danish Adoption Register

    DEFF Research Database (Denmark)

    Petersen, Liselotte; Sørensen, Thorkild I A

    2011-01-01

    The Danish Adoption Register was established in 1963-1964 to explore the genetic and environmental contribution to familial aggregation of schizophrenia.......The Danish Adoption Register was established in 1963-1964 to explore the genetic and environmental contribution to familial aggregation of schizophrenia....

  10. Biometrics-based service marketing issues: exploring acceptability and risk factors of iris scans associated with registered travel programmes.

    Science.gov (United States)

    Smith, Alan D

    2008-01-01

    The marketability and viability of biometric technologies by companies marketing their own versions of pre-approved registered travel programmes have generated a number of controversies. Data were collected and analysed to formulate graphs, run regression and correlation analyses, and use Chi-square to formally test basic research propositions on a sample of 241 professionals in the Pittsburgh area. It was found that there was a significant relationship between the respondents' familiarity with new technology (namely web-enabled and internet sophistication) and knowledge of biometrics, in particular iris scans. Participants who frequently use the internet are more comfortable with innovative technology; although individuals with higher income levels have less trust in the government, it appeared that virtually everyone is concerned about trusting the government with their personal information. Healthcare professionals need to document the safety, CRM-related factors, and provide leadership in the international collaboration of biometric-related personal identification technologies, since they will be one of the main beneficiaries of the implementation of such technologies.

  11. A model of survival following pre-hospital cardiac arrest based on the Victorian Ambulance Cardiac Arrest Register.

    Science.gov (United States)

    Fridman, Masha; Barnes, Vanessa; Whyman, Andrew; Currell, Alex; Bernard, Stephen; Walker, Tony; Smith, Karen L

    2007-11-01

    This study describes the epidemiology of sudden cardiac arrest patients in Victoria, Australia, as captured via the Victorian Ambulance Cardiac Arrest Register (VACAR). We used the VACAR data to construct a new model of out-of-hospital cardiac arrest (OHCA), which was specified in accordance with observed trends. All cases of cardiac arrest in Victoria that were attended by Victorian ambulance services during the period of 2002-2005. Overall survival to hospital discharge was 3.8% among 18,827 cases of OHCA. Survival was 15.7% among 1726 bystander witnessed, adult cardiac arrests of presumed cardiac aetiology, presenting in ventricular fibrillation or ventricular tachycardia (VF/VT), where resuscitation was attempted. In multivariate logistic regression analysis, bystander CPR, cardiac arrest (CA) location, response time, age and sex were predictors of VF/VT, which, in turn, was a strong predictor of survival. The same factors that affected VF/VT made an additional contribution to survival. However, for bystander CPR, CA location and response time this additional contribution was limited to VF/VT patients only. There was no detectable association between survival and age younger than 60 years or response time over 15min. The new model accounts for relationships among predictors of survival. These relationships indicate that interventions such as reduced response times and bystander CPR act in multiple ways to improve survival.

  12. Early life risk factors for testicular cancer: a case-cohort study based on the Copenhagen School Health Records Register.

    Science.gov (United States)

    Piltoft, Johanne Spanggaard; Larsen, Signe Benzon; Dalton, Susanne Oksbjerg; Johansen, Christoffer; Baker, Jennifer L; Cederkvist, Luise; Andersen, Ingelise

    2017-02-01

    One established risk factors for testicular cancer is cryptorchidism. However, it remains unclear whether cryptorchidism is a risk factor in itself or whether the two conditions share common causes in early life (estrogen hypothesis), such as birth weight and birth order. The objective of this study is to utilize data from the Copenhagen School Health Records Register (CSHRR) to evaluate cryptorchidism, birth weight and birth order as risk factors for testicular cancer. The study population consisted of 408 cases of testicular cancer identified by a government issued identification number linkage of the entire CSHRR with the Danish Cancer Registry and a random subsample of 4819 males from the CSHRR. The study design was case-cohort and the period of follow-up between 2 April 1968 and 31 December 2003. Cryptorchidism was significantly associated with testicular cancer in crude analyses [hazard ratio (HR) = 3.60, 95% CI 2.79-4.65]. Birth weight was inversely associated with testicular cancer and no clear association with birth order was observed. The positive association between cryptorchidism and testicular cancer was only slightly attenuated controlling for birth weight and birth order and stratified on birth cohort (HR = 3.46, 95% CI 2.67-4.48). This study confirmed the robustness of the association between cryptorchidism and testicular cancer even after adjustment for birth weight and birth order. Furthermore, the study showed an inverse association between birth weight and testicular cancer.

  13. High mortality among people suspected of drunk-driving. An 18-year register-based follow-up.

    Science.gov (United States)

    Impinen, Antti; Mäkelä, Pia; Karjalainen, Karoliina; Rahkonen, Ossi; Lintonen, Tomi; Lillsunde, Pirjo; Ostamo, Aini

    2010-07-01

    The aim of this study was to examine the overall and cause-specific mortality of DUI arrestees compared to a reference population with no history of DUI and to recognize the risk factors of premature death. The data used were a register of all DUI arrestees between April 1988 and December 2006. All drivers with drug-positive samples were excluded. DUI arrestees were compared to a reference population with no previous history of DUI. Overall and cause-specific hazard ratios were calculated and risk factors were estimated. Alcohol causes, diseases of the circulatory system and accidents constituted the most common causes of death among DUI arrestees. Suspected DUI was linked with higher mortality in every observed cause of death. The risk of death by alcohol-related or external cause was especially high. Among women DUI arrests caused sharper increase to the risk of death than increase found among male arrestees. Within the group of DUI arrestees the risk of death was affected by age, sex, marital status, education, multiple arrests as well as time and observed blood alcohol level of the arrest. Half of the suspected DUI cases and one in five of the references had alcohol as a contributing factor to death. Arrest on suspicion of drunk-driving is an indicator for elevated risk of death. Alcohol is often related to deaths of DUI arrestees. Drunk-drivers should be efficiently guided with respect to evaluations and treatments for harmful drinking. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Fundamental limits on quantum dynamics based on entropy change

    Science.gov (United States)

    Das, Siddhartha; Khatri, Sumeet; Siopsis, George; Wilde, Mark M.

    2018-01-01

    It is well known in the realm of quantum mechanics and information theory that the entropy is non-decreasing for the class of unital physical processes. However, in general, the entropy does not exhibit monotonic behavior. This has restricted the use of entropy change in characterizing evolution processes. Recently, a lower bound on the entropy change was provided in the work of Buscemi, Das, and Wilde [Phys. Rev. A 93(6), 062314 (2016)]. We explore the limit that this bound places on the physical evolution of a quantum system and discuss how these limits can be used as witnesses to characterize quantum dynamics. In particular, we derive a lower limit on the rate of entropy change for memoryless quantum dynamics, and we argue that it provides a witness of non-unitality. This limit on the rate of entropy change leads to definitions of several witnesses for testing memory effects in quantum dynamics. Furthermore, from the aforementioned lower bound on entropy change, we obtain a measure of non-unitarity for unital evolutions.

  15. Bounding quantum gate error rate based on reported average fidelity

    International Nuclear Information System (INIS)

    Sanders, Yuval R; Wallman, Joel J; Sanders, Barry C

    2016-01-01

    Remarkable experimental advances in quantum computing are exemplified by recent announcements of impressive average gate fidelities exceeding 99.9% for single-qubit gates and 99% for two-qubit gates. Although these high numbers engender optimism that fault-tolerant quantum computing is within reach, the connection of average gate fidelity with fault-tolerance requirements is not direct. Here we use reported average gate fidelity to determine an upper bound on the quantum-gate error rate, which is the appropriate metric for assessing progress towards fault-tolerant quantum computation, and we demonstrate that this bound is asymptotically tight for general noise. Although this bound is unlikely to be saturated by experimental noise, we demonstrate using explicit examples that the bound indicates a realistic deviation between the true error rate and the reported average fidelity. We introduce the Pauli distance as a measure of this deviation, and we show that knowledge of the Pauli distance enables tighter estimates of the error rate of quantum gates. (fast track communication)

  16. Heralded linear optical quantum Fredkin gate based on one auxiliary qubit and one single photon detector

    International Nuclear Information System (INIS)

    Zhu Chang-Hua; Cao Xin; Quan Dong-Xiao; Pei Chang-Xing

    2014-01-01

    Linear optical quantum Fredkin gate can be applied to quantum computing and quantum multi-user communication networks. In the existing linear optical scheme, two single photon detectors (SPDs) are used to herald the success of the quantum Fredkin gate while they have no photon count. But analysis results show that for non-perfect SPD, the lower the detector efficiency, the higher the heralded success rate by this scheme is. We propose an improved linear optical quantum Fredkin gate by designing a new heralding scheme with an auxiliary qubit and only one SPD, in which the higher the detection efficiency of the heralding detector, the higher the success rate of the gate is. The new heralding scheme can also work efficiently under a non-ideal single photon source. Based on this quantum Fredkin gate, large-scale quantum switching networks can be built. As an example, a quantum Beneš network is shown in which only one SPD is used. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  17. Josephson shift registers

    International Nuclear Information System (INIS)

    Przybysz, J.X.

    1989-01-01

    This paper gives a review of Josephson shift register circuits that were designed, fabricated, or tested, with emphasis on work in the 1980s. Operating speed is most important, since it often limits system performance. Older designs used square-wave clocks, but most modern designs use offset sine waves, with either two or three phases. Operating margins and gate bias uniformity are key concerns. The fastest measured Josephson shift register operated at 2.3 GHz, which compares well with a GaAs shift register that consumes 250 times more power. The difficulties of high-speed testing have prevented many Josephson shift registers from being operated at their highest speeds. Computer simulations suggest that 30-GHz operation is possible with current Nb/Al 2 O 3 /Nb technology. Junctions with critical current densities near 10 kA/cm 2 would make 100-GHz shift registers feasible

  18. Quantum-key-distribution protocol with pseudorandom bases

    Science.gov (United States)

    Trushechkin, A. S.; Tregubov, P. A.; Kiktenko, E. O.; Kurochkin, Y. V.; Fedorov, A. K.

    2018-01-01

    Quantum key distribution (QKD) offers a way for establishing information-theoretical secure communications. An important part of QKD technology is a high-quality random number generator for the quantum-state preparation and for post-processing procedures. In this work, we consider a class of prepare-and-measure QKD protocols, utilizing additional pseudorandomness in the preparation of quantum states. We study one of such protocols and analyze its security against the intercept-resend attack. We demonstrate that, for single-photon sources, the considered protocol gives better secret key rates than the BB84 and the asymmetric BB84 protocols. However, the protocol strongly requires single-photon sources.

  19. A trajectory-based understanding of quantum interference

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, A S; Miret-Artes, S [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones CientIficas, Serrano 123, 28006 Madrid (Spain)], E-mail: asanz@imaff.cfmac.csic.es, E-mail: s.miret@imaff.cfmac.csic.es

    2008-10-31

    Interference is one of the most fundamental features which characterizes quantum systems. Here we provide an exhaustive analysis of the interfere dynamics associated with wave-packet superpositions from both the standard quantum-mechanical perspective and the Bohmian one. From this analysis, clear and insightful pictures of the physics involved in these kind of processes are obtained, which are of general validity (i.e., regardless of the type of wave packets considered) in the understanding of more complex cases where interference is crucial (e.g., scattering problems, slit diffraction, quantum control scenarios or, even, multipartite interactions). In particular, we show how problems involving wave-packet interference can be mapped onto problems of wave packets scattered off potential barriers.

  20. Network-based Arbitrated Quantum Signature Scheme with Graph State

    Science.gov (United States)

    Ma, Hongling; Li, Fei; Mao, Ningyi; Wang, Yijun; Guo, Ying

    2017-08-01

    Implementing an arbitrated quantum signature(QAS) through complex networks is an interesting cryptography technology in the literature. In this paper, we propose an arbitrated quantum signature for the multi-user-involved networks, whose topological structures are established by the encoded graph state. The determinative transmission of the shared keys, is enabled by the appropriate stabilizers performed on the graph state. The implementation of this scheme depends on the deterministic distribution of the multi-user-shared graph state on which the encoded message can be processed in signing and verifying phases. There are four parties involved, the signatory Alice, the verifier Bob, the arbitrator Trent and Dealer who assists the legal participants in the signature generation and verification. The security is guaranteed by the entanglement of the encoded graph state which is cooperatively prepared by legal participants in complex quantum networks.

  1. N-state random switching based on quantum tunnelling

    Science.gov (United States)

    Bernardo Gavito, Ramón; Jiménez Urbanos, Fernando; Roberts, Jonathan; Sexton, James; Astbury, Benjamin; Shokeir, Hamzah; McGrath, Thomas; Noori, Yasir J.; Woodhead, Christopher S.; Missous, Mohamed; Roedig, Utz; Young, Robert J.

    2017-08-01

    In this work, we show how the hysteretic behaviour of resonant tunnelling diodes (RTDs) can be exploited for new functionalities. In particular, the RTDs exhibit a stochastic 2-state switching mechanism that could be useful for random number generation and cryptographic applications. This behaviour can be scaled to N-bit switching, by connecting various RTDs in series. The InGaAs/AlAs RTDs used in our experiments display very sharp negative differential resistance (NDR) peaks at room temperature which show hysteresis cycles that, rather than having a fixed switching threshold, show a probability distribution about a central value. We propose to use this intrinsic uncertainty emerging from the quantum nature of the RTDs as a source of randomness. We show that a combination of two RTDs in series results in devices with three-state outputs and discuss the possibility of scaling to N-state devices by subsequent series connections of RTDs, which we demonstrate for the up to the 4-state case. In this work, we suggest using that the intrinsic uncertainty in the conduction paths of resonant tunnelling diodes can behave as a source of randomness that can be integrated into current electronics to produce on-chip true random number generators. The N-shaped I-V characteristic of RTDs results in a two-level random voltage output when driven with current pulse trains. Electrical characterisation and randomness testing of the devices was conducted in order to determine the validity of the true randomness assumption. Based on the results obtained for the single RTD case, we suggest the possibility of using multi-well devices to generate N-state random switching devices for their use in random number generation or multi-valued logic devices.

  2. Influence of qubit displacements on quantum logic operations in a silicon-based quantum computer with constant interaction

    International Nuclear Information System (INIS)

    Kamenev, D. I.; Berman, G. P.; Tsifrinovich, V. I.

    2006-01-01

    The errors caused by qubit displacements from their prescribed locations in an ensemble of spin chains are estimated analytically and calculated numerically for a quantum computer based on phosphorus donors in silicon. We show that it is possible to polarize (initialize) the nuclear spins even with displaced qubits by using controlled-NOT gates between the electron and nuclear spins of the same phosphorus atom. However, a controlled-NOT gate between the displaced electron spins is implemented with large error because of the exponential dependence of exchange interaction constant on the distance between the qubits. If quantum computation is implemented on an ensemble of many spin chains, the errors can be small if the number of chains with displaced qubits is small

  3. Academic Achievement in Primary School in Offspring Born to Mothers With Type 1 Diabetes (the EPICOM Study): A Register-Based Prospective Cohort Study

    DEFF Research Database (Denmark)

    Knorr, Sine; Clausen, Tine D; Vlachová, Zuzana

    2015-01-01

    OBJECTIVE: This study examined the effect of maternal pregestational type 1 diabetes on offspring primary school performance. RESEARCH DESIGN AND METHODS: We performed a prospective combined clinical and register-based cohort study comparing primary school performance in offspring (n = 707......) of women with pregestational type 1 diabetes with matched control offspring (n = 60,341). We also examined the association between HbA1c levels during pregnancy and later school performance among offspring born to women with pregestational type 1 diabetes. RESULTS: Offspring of mothers with pregestational...

  4. Quantum-dot based nanothermometry in optical plasmonic recording media

    International Nuclear Information System (INIS)

    Maestro, Laura Martinez; Zhang, Qiming; Li, Xiangping; Gu, Min; Jaque, Daniel

    2014-01-01

    We report on the direct experimental determination of the temperature increment caused by laser irradiation in a optical recording media constituted by a polymeric film in which gold nanorods have been incorporated. The incorporation of CdSe quantum dots in the recording media allowed for single beam thermal reading of the on-focus temperature from a simple analysis of the two-photon excited fluorescence of quantum dots. Experimental results have been compared with numerical simulations revealing an excellent agreement and opening a promising avenue for further understanding and optimization of optical writing processes and media

  5. Heterogeneity in 10-Year Course Trajectories of Moderate to Severe Major Depressive Disorder: A Danish National Register-Based Study.

    Science.gov (United States)

    Musliner, Katherine L; Munk-Olsen, Trine; Laursen, Thomas M; Eaton, William W; Zandi, Peter P; Mortensen, Preben B

    2016-04-01

    Evidence suggests that long-term trajectories of major depressive disorder (MDD) are heterogeneous. The Danish Psychiatric Central Research Register (DPCRR) provides a rare opportunity to examine patterns and correlates of long-term trajectories in a large sample of patients with moderate to severe MDD. To characterize patterns and correlates of 10-year course trajectories of MDD in the DPCRR. A cohort containing 11 640 individuals born in Denmark in 1955 or later with their first recorded MDD diagnosis in the DPCRR between 1995 and 2002 was established. Patients were followed for 10 years from the date of their initial MDD diagnosis. Data were obtained from Danish civil and psychiatric national registers in June 2013 and were analyzed from April 4, 2014, to December 17, 2015. Correlates of trajectory class membership were sex, characteristics of the first recorded MDD episode (ie, age, severity, inpatient treatment, and record of suicide attempt or self-harm), and psychiatric diagnoses in parents (ie, depression, bipolar disorder, schizophrenia-spectrum disorders, substance abuse, and anxiety or somatoform disorders). The outcome variable was past-year contact at a psychiatric hospital with a main diagnosis of MDD during each of the 10 years following the initial MDD diagnosis. Trajectories were modeled using latent class growth analysis. The sample included 11 640 individuals (7493 [64.4%] women) aged 18 to 48 years (mean [SD], 31.4 [7.3]) at their first recorded MDD diagnosis. Four trajectory classes were identified: brief contact (77.0%) (characterized by low probability of contact after 2 years); prolonged initial contact (12.8%) (characterized by high decreasing probability of contact during the first 5 years); later reentry (7.1%) (characterized by moderate probability of contact during the second 5 years); and persistent contact (3.1%) (characterized by high or moderate probability of contact throughout). Female sex (odds ratio [OR] range, 1

  6. Solar Cells Based on Inks of n-Type Colloidal Quantum Dots

    KAUST Repository

    Ning, Zhijun; Dong, Haopeng; Zhang, Qiong; Voznyy, Oleksandr; Sargent, Edward H.

    2014-01-01

    © 2014 American Chemical Society. New inorganic ligands including halide anions have significantly accelerated progress in colloidal quantum dot (CQD) photovoltaics in recent years. All such device reports to date have relied on halide treatment during solid-state ligand exchanges or on co-treatment of long-aliphatic-ligand-capped nanoparticles in the solution phase. Here we report solar cells based on a colloidal quantum dot ink that is capped using halide-based ligands alone. By judicious choice of solvents and ligands, we developed a CQD ink from which a homogeneous and thick colloidal quantum dot solid is applied in a single step. The resultant films display an n-type character, making it suitable as a key component in a solar-converting device. We demonstrate two types of quantum junction devices that exploit these iodide-ligand-based inks. We achieve solar power conversion efficiencies of 6% using this class of colloids.

  7. Solar Cells Based on Inks of n-Type Colloidal Quantum Dots

    KAUST Repository

    Ning, Zhijun

    2014-10-28

    © 2014 American Chemical Society. New inorganic ligands including halide anions have significantly accelerated progress in colloidal quantum dot (CQD) photovoltaics in recent years. All such device reports to date have relied on halide treatment during solid-state ligand exchanges or on co-treatment of long-aliphatic-ligand-capped nanoparticles in the solution phase. Here we report solar cells based on a colloidal quantum dot ink that is capped using halide-based ligands alone. By judicious choice of solvents and ligands, we developed a CQD ink from which a homogeneous and thick colloidal quantum dot solid is applied in a single step. The resultant films display an n-type character, making it suitable as a key component in a solar-converting device. We demonstrate two types of quantum junction devices that exploit these iodide-ligand-based inks. We achieve solar power conversion efficiencies of 6% using this class of colloids.

  8. Labor market position after a rejection of a disability pension application: a register-based cohort study.

    Science.gov (United States)

    Laaksonen, Mikko; Gould, Raija; Liukko, Jyri

    2017-08-17

    To study labor market positions of rejected disability pension applicants and to examine which characteristics predict ending up in these positions after the rejection. Nationwide Finnish register data was used to describe employment, unemployment and disability pension trajectories of rejected applicants (n = 5740) from four years before to four years after the rejection. Demographic, occupational and health-related determinants of labor market position after the rejection were examined among those employed and not employed at the time of the rejection. The proportion of the employed steeply decreased and that of unemployed increased before the rejection of a disability pension application. Four years after the rejection, 30% of the rejected applicants were employed, 24% were unemployed and 30% received disability pension. Employment at the time of the rejection, younger age, shorter unemployment history, public sector employment and milder work disability increased future employment. Manual work, public sector employment and previous long-term unemployment predicted future unemployment. Apart from higher age, associations with receiving disability pension were relatively weak. For many rejected disability pension applicants return to work is challenging. Special efforts should be targeted to support the remaining work ability and to promote employment opportunities of the rejected applicants. Implications for Rehabilitation Employment, unemployment and receiving disability pension were equally common labor market positions four years after the rejection. Rejected DP applicants with unemployment history need special efforts to increase their employability. As a disability pension application, even if rejected, clearly indicates some degree of work ability problems, rehabilitation should be targeted at this time point to support employment.

  9. Risk of labor dystocia increases with maternal age irrespective of parity: a population-based register study.

    Science.gov (United States)

    Waldenström, Ulla; Ekéus, Cecilia

    2017-09-01

    Advanced maternal age is associated with labor dystocia (LD) in nulliparous women. This study investigates the age-related risk of LD in first, second and third births. All live singleton cephalic births at term (≥ 37 gestational weeks) recorded in the Swedish Medical Birth Register from 1999 to 2011, except elective cesarean sections and fourth births and more, in total 998 675 pregnancies, were included in the study. LD was defined by International Classification of Diseases, version 10 codes (O620, O621, O622, O629, O630, O631 and O639). In each parity group risks of LD at age 25-29 years, 30-34 years, 35-39 years and ≥ 40 years compared with age < 25 years were investigated by logistic regression analyses. Analyses were adjusted for year of delivery, education, country/region of birth, smoking in early pregnancy, maternal height, body mass index, week of gestation, fetal presentation and infant birthweight. Rates of LD were 22.5%, 6.1% and 4% in first, second and third births, respectively. Adjusted odd ratios (OR) for LD increased progressively from the youngest to the oldest age group, irrespective of parity. At age 35-39 years the adjusted OR (95% CI) was approximately doubled compared with age 25 and younger: 2.13 (2.06-2.20) in first birth; 2.05 (1.91-2.19) in second births; and 1.81 (1.49-2.21) in third births. Maternal age is an independent risk factor for LD in first, second and third births. Although age-related risks by parity are relatively similar, more nulliparous than parous women will be exposed to LD due to the higher rate. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

  10. Drug use in patients with dementia: a register-based study in the health region of Girona (Catalonia/Spain).

    Science.gov (United States)

    Avila-Castells, Pilar; Garre-Olmo, Josep; Calvó-Perxas, Laia; Turró-Garriga, Oriol; Alsina, Elisabet; Carmona, Olga; Perkal, Héctor; Roig, Anna Maria; Cuy, Josep Ma; Lozano, Manuela; Molins, Albert; Vallmajó, Natàlia; López-Pousa, Secundino

    2013-05-01

    To describe the pattern of drug consumption among patients with dementia in a geographically defined general population in Catalonia (Spain), and to determine its association with age, gender, type of dementia and severity indicators. Cross-sectional study that included 1,894 cases of dementia registered by the Registry of Dementias of Girona from 2007 to 2009. Prescribed drugs were categorized according to the Anatomical Therapeutic Chemical (ATC) classification. A descriptive analysis of drug consumption was stratified according to age, gender, dementia subtypes and dementia severity. Binary logistic regression models were adjusted to detect the association of these variables with drug consumption according to the ATC groups. The most commonly prescribed drugs were for the central nervous system (CNS) (96.4 %), cardiovascular system (79.4 %) and digestive and metabolic system categories (77.7 %). No significant differences were found between the use of nervous system drugs and age, gender, dementia subtypes or dementia severity. The use of alimentary tract and metabolism related drugs, as well as cardiovascular and blood system drugs, were positively correlated with age and secondary dementia. The prevalence of use of cardiovascular and musculoskeletal drugs was higher in women than in men (OR: 1.34; OR: 1.26 respectively). A negative association was found between the severity of dementia and the use of musculoskeletal drugs (OR: 0.71), while its use was significantly higher in the youngest patients (OR: 1.71). Almost all patients with dementia received a CNS drug, being at risk of inappropriate treatment. Treatment for comorbidities in patients with dementia should not be withheld on the basis of age or dementia severity, but rather on the benefit/risk ratio of its prescription. Further studies are needed to evaluate potentially inappropriate drug use and possible untreated conditions in this population.

  11. Determinants of duration of untreated psychosis among first-episode psychosis patients in Denmark: A nationwide register-based study.

    Science.gov (United States)

    Hastrup, Lene Halling; Haahr, Ulrik Helt; Jansen, Jens Einar; Simonsen, Erik

    2018-02-01

    Information on determinants of duration of untreated psychosis (DUP) is still needed to inform campaigns targeting people with first episode psychosis (FEP). This nation-wide study analysed the association between demographic factors (age, sex, ethnicity, marital status, and geographic area), premorbid and illness-related factors (global functional level, substance misuse, and contact to police), healthcare factors (referral source and first FEP contact) and DUP. The study population of 1266 patients aged 15-25years diagnosed with FEP (ICD10 F20.0-F20.99) was drawn from the Danish National Indicator Project during 2009-2011. The study population was combined with data from national administrative registers. A multinomial regression model was estimated to analyse the impact of demographic, premorbid and illness-related, and healthcare factors on DUP. One third of the population had a DUP below 6months. DUP longer than 12months was associated with older age at onset, being female, having cannabis misuse, and living in peripheral municipalities. Being charged by the criminal authorities during one year before FEP was associated with a DUP over 6months. DUP is related to a number of demographic, premorbid and healthcare factors. These findings suggest that future information campaigns should focus on increasing the awareness of early signs of psychosis not only among mental health professionals but also other professionals in contact with adolescents such as the police. It may also be useful to consider how to target information campaigns towards persons living in peripheral areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Towards scalable quantum communication and computation: Novel approaches and realizations

    Science.gov (United States)

    Jiang, Liang

    Quantum information science involves exploration of fundamental laws of quantum mechanics for information processing tasks. This thesis presents several new approaches towards scalable quantum information processing. First, we consider a hybrid approach to scalable quantum computation, based on an optically connected network of few-qubit quantum registers. Specifically, we develop a novel scheme for scalable quantum computation that is robust against various imperfections. To justify that nitrogen-vacancy (NV) color centers in diamond can be a promising realization of the few-qubit quantum register, we show how to isolate a few proximal nuclear spins from the rest of the environment and use them for the quantum register. We also demonstrate experimentally that the nuclear spin coherence is only weakly perturbed under optical illumination, which allows us to implement quantum logical operations that use the nuclear spins to assist the repetitive-readout of the electronic spin. Using this technique, we demonstrate more than two-fold improvement in signal-to-noise ratio. Apart from direct application to enhance the sensitivity of the NV-based nano-magnetometer, this experiment represents an important step towards the realization of robust quantum information processors using electronic and nuclear spin qubits. We then study realizations of quantum repeaters for long distance quantum communication. Specifically, we develop an efficient scheme for quantum repeaters based on atomic ensembles. We use dynamic programming to optimize various quantum repeater protocols. In addition, we propose a new protocol of quantum repeater with encoding, which efficiently uses local resources (about 100 qubits) to identify and correct errors, to achieve fast one-way quantum communication over long distances. Finally, we explore quantum systems with topological order. Such systems can exhibit remarkable phenomena such as quasiparticles with anyonic statistics and have been proposed as

  13. Bit-Oriented Quantum Public-Key Cryptosystem Based on Bell States

    Science.gov (United States)

    Wu, WanQing; Cai, QingYu; Zhang, HuanGuo; Liang, XiaoYan

    2018-06-01

    Quantum public key encryption system provides information confidentiality using quantum mechanics. This paper presents a quantum public key cryptosystem ( Q P K C) based on the Bell states. By H o l e v o' s theorem, the presented scheme provides the security of the secret key using one-wayness during the QPKC. While the QPKC scheme is information theoretic security under chosen plaintext attack ( C P A). Finally some important features of presented QPKC scheme can be compared with other QPKC scheme.

  14. Hybrid Approach To Steganography System Based On Quantum Encryption And Chaos Algorithms

    Directory of Open Access Journals (Sweden)

    ZAID A. ABOD

    2018-01-01

    Full Text Available A hybrid scheme for secretly embedding image into a dithered multilevel image is presented. This work inputs both a cover image and secret image, which are scrambling and divided into groups to embedded together based on multiple chaos algorithms (Lorenz map, Henon map and Logistic map respectively. Finally, encrypt the embedded images by using one of the quantum cryptography mechanisms, which is quantum one time pad. The experimental results show that the proposed hybrid system successfully embedded images and combine with the quantum cryptography algorithms and gives high efficiency for secure communication.

  15. A Gleason-Type Theorem for Any Dimension Based on a Gambling Formulation of Quantum Mechanics

    Science.gov (United States)

    Benavoli, Alessio; Facchini, Alessandro; Zaffalon, Marco

    2017-07-01

    Based on a gambling formulation of quantum mechanics, we derive a Gleason-type theorem that holds for any dimension n of a quantum system, and in particular for n=2. The theorem states that the only logically consistent probability assignments are exactly the ones that are definable as the trace of the product of a projector and a density matrix operator. In addition, we detail the reason why dispersion-free probabilities are actually not valid, or rational, probabilities for quantum mechanics, and hence should be excluded from consideration.

  16. Design and Fabrication of Multi Quantum well based GaN/InGaN Blue LED

    Science.gov (United States)

    Meel, K.; Mahala, P.; Singh, S.

    2018-03-01

    This paper presents the optimization of the multi-quantum well based Light Emitting Diode (LED) structure. We investigate the electrical and optical properties of the device on several factors like well width, barrier width, the number of quantum wells and then optimize the structure. The device is optimized for a well width and barrier width of 3nm and 6nm respectively, consisting of five quantum wells. Simulations were carried out using Silvaco ATLAS TCAD simulation program (Silvaco International, USA). The optimized structure was grown by MOCVD and fabricated. The I-V characteristic was also measured.

  17. High-dimensional quantum key distribution based on multicore fiber using silicon photonic integrated circuits

    DEFF Research Database (Denmark)

    Ding, Yunhong; Bacco, Davide; Dalgaard, Kjeld

    2017-01-01

    is intrinsically limited to 1 bit/photon. Here we propose and experimentally demonstrate, for the first time, a high-dimensional quantum key distribution protocol based on space division multiplexing in multicore fiber using silicon photonic integrated lightwave circuits. We successfully realized three mutually......-dimensional quantum states, and enables breaking the information efficiency limit of traditional quantum key distribution protocols. In addition, the silicon photonic circuits used in our work integrate variable optical attenuators, highly efficient multicore fiber couplers, and Mach-Zehnder interferometers, enabling...

  18. Quantum deterministic key distribution protocols based on the authenticated entanglement channel

    International Nuclear Information System (INIS)

    Zhou Nanrun; Wang Lijun; Ding Jie; Gong Lihua

    2010-01-01

    Based on the quantum entanglement channel, two secure quantum deterministic key distribution (QDKD) protocols are proposed. Unlike quantum random key distribution (QRKD) protocols, the proposed QDKD protocols can distribute the deterministic key securely, which is of significant importance in the field of key management. The security of the proposed QDKD protocols is analyzed in detail using information theory. It is shown that the proposed QDKD protocols can safely and effectively hand over the deterministic key to the specific receiver and their physical implementation is feasible with current technology.

  19. Quantum deterministic key distribution protocols based on the authenticated entanglement channel

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Nanrun; Wang Lijun; Ding Jie; Gong Lihua [Department of Electronic Information Engineering, Nanchang University, Nanchang 330031 (China)], E-mail: znr21@163.com, E-mail: znr21@hotmail.com

    2010-04-15

    Based on the quantum entanglement channel, two secure quantum deterministic key distribution (QDKD) protocols are proposed. Unlike quantum random key distribution (QRKD) protocols, the proposed QDKD protocols can distribute the deterministic key securely, which is of significant importance in the field of key management. The security of the proposed QDKD protocols is analyzed in detail using information theory. It is shown that the proposed QDKD protocols can safely and effectively hand over the deterministic key to the specific receiver and their physical implementation is feasible with current technology.

  20. An efficient deterministic secure quantum communication scheme based on cluster states and identity authentication

    International Nuclear Information System (INIS)

    Wen-Jie, Liu; Han-Wu, Chen; Zhi-Qiang, Li; Zhi-Hao, Liu; Wen-Bo, Hu; Ting-Huai, Ma

    2009-01-01

    A novel efficient deterministic secure quantum communication scheme based on four-qubit cluster states and single-photon identity authentication is proposed. In this scheme, the two authenticated users can transmit two bits of classical information per cluster state, and its efficiency of the quantum communication is 1/3, which is approximately 1.67 times that of the previous protocol presented by Wang et al [Chin. Phys. Lett. 23 (2006) 2658]. Security analysis shows the present scheme is secure against intercept-resend attack and the impersonator's attack. Furthermore, it is more economic with present-day techniques and easily processed by a one-way quantum computer. (general)

  1. A Third-Party E-Payment Protocol Based on Quantum Group Blind Signature

    Science.gov (United States)

    Zhang, Jian-Zhong; Yang, Yuan-Yuan; Xie, Shu-Cui

    2017-09-01

    A third-party E-payment protocol based on quantum group blind signature is proposed in this paper. Our E-payment protocol could protect user's anonymity as the traditional E-payment systems do, and also have unconditional security which the classical E-payment systems can not provide. To achieve that, quantum key distribution, one-time pad and quantum group blind signature are adopted in our scheme. Furthermore, if there were a dispute, the manager Trent can identify who tells a lie.

  2. Visualization of reaction mechanism by CG based on quantum ...

    African Journals Online (AJOL)

    In this work, the change in the molecular configuration in fundamental chemical reactions such as, F + HCl ¨ HF + Cl, I + H2¨ HI + H, OH- + CH3Cl ¨ CH3OH + Cl-, and esterification of acetic acid and ethyl alcohol were visualized by the quantum chemical calculation MOPAC with PM5 Hamiltonian. The CG teaching material ...

  3. Photonic emitters and circuits based on colloidal quantum dot composites

    Science.gov (United States)

    Menon, Vinod M.; Husaini, Saima; Valappil, Nikesh; Luberto, Matthew

    2009-02-01

    We discuss our work on light emitters and photonic circuits realized using colloidal quantum dot composites. Specifically we will report our recent work on flexible microcavity laser, microdisk emitters and integrated active - passive waveguides. The entire microcavity laser structure was realized using spin coating and consisted of an all-polymer distributed Bragg reflector with a poly-vinyl carbazole cavity layer embedded with InGaP/ZnS colloidal quantum dots. These microcavities can be peeled off the substrate yielding a flexible structure that can conform to any shape and whose emission spectra can be mechanically tuned. The microdisk emitters and the integrated waveguide structures were realized using soft lithography and photo-lithography, respectively and were fabricated using a composite consisting of quantum dots embedded in SU8 matrix. Finally, we will discuss the effect of the host matrix on the optical properties of the quantum dots using results of steady-state and time-resolved luminescence measurements. In addition to their specific functionalities, these novel device demonstrations and their development present a low cost alternative to the traditional photonic device fabrication techniques.

  4. Sick Leave within 5 Years of Whiplash Trauma Predicts Recovery: A Prospective Cohort and Register-Based Study.

    Science.gov (United States)

    Carstensen, Tina Birgitte Wisbech; Fink, Per; Oernboel, Eva; Kasch, Helge; Jensen, Troels Staehelin; Frostholm, Lisbeth

    2015-01-01

    10-22% of individuals sustaining whiplash trauma develop persistent symptoms resulting in reduced working ability and decreased quality of life, but it is poorly understood why some people do not recover. Various collision and post-collision risk factors have been studied, but little is known about pre-collision risk factors. In particular, the impact of sickness and socioeconomic factors before the collision on recovery is sparsely explored. The aim of this study was to examine if welfare payments received within five years pre-collision predict neck pain and negative change in provisional situation one year post-collision. 719 individuals with acute whiplash trauma consecutively recruited from emergency departments or primary care after car accidents in Denmark completed questionnaires on socio-demographic and health factors immediately after the collision. After 12 months, a visual analogue scale on neck pain intensity was completed. 3595 matched controls in the general population were sampled, and national public register data on social benefits and any other welfare payments were obtained for participants with acute whiplash trauma and controls from five years pre-collision to 15 months after. Participants with acute whiplash trauma who had received sickness benefit for more than 12 weeks pre-collision had increased odds for negative change in future provisional situation (Odds Ratio (OR) (95% Confidence Interval (CI) = 3.8 (2.1;7.1)) and future neck pain (OR (95%CI) = 3.3 (1.8;6.3)), controlling for other known risk factors. Participants with acute whiplash trauma had weaker attachment to labour market (more weeks of sick leave (χ2(2) = 36.7, p whiplash trauma raised the odds for future negative change in provisional situation (OR (95%CI) = 3.1 (2.3;4.4)) compared with controls. Sick leave before the collision strongly predicted prolonged recovery following whiplash trauma. Participants with acute whiplash trauma had weaker attachment to labour market pre

  5. Sick Leave within 5 Years of Whiplash Trauma Predicts Recovery: A Prospective Cohort and Register-Based Study

    Science.gov (United States)

    Carstensen, Tina Birgitte Wisbech; Fink, Per; Oernboel, Eva; Kasch, Helge; Jensen, Troels Staehelin; Frostholm, Lisbeth

    2015-01-01

    Background 10–22% of individuals sustaining whiplash trauma develop persistent symptoms resulting in reduced working ability and decreased quality of life, but it is poorly understood why some people do not recover. Various collision and post-collision risk factors have been studied, but little is known about pre-collision risk factors. In particular, the impact of sickness and socioeconomic factors before the collision on recovery is sparsely explored. The aim of this study was to examine if welfare payments received within five years pre-collision predict neck pain and negative change in provisional situation one year post-collision. Methods and Findings 719 individuals with acute whiplash trauma consecutively recruited from emergency departments or primary care after car accidents in Denmark completed questionnaires on socio-demographic and health factors immediately after the collision. After 12 months, a visual analogue scale on neck pain intensity was completed. 3595 matched controls in the general population were sampled, and national public register data on social benefits and any other welfare payments were obtained for participants with acute whiplash trauma and controls from five years pre-collision to 15 months after. Participants with acute whiplash trauma who had received sickness benefit for more than 12 weeks pre-collision had increased odds for negative change in future provisional situation (Odds Ratio (OR) (95% Confidence Interval (CI) = 3.8 (2.1;7.1)) and future neck pain (OR (95%CI) = 3.3 (1.8;6.3)), controlling for other known risk factors. Participants with acute whiplash trauma had weaker attachment to labour market (more weeks of sick leave (χ2(2) = 36.7, p whiplash trauma raised the odds for future negative change in provisional situation (OR (95%CI) = 3.1 (2.3;4.4)) compared with controls. Conclusions Sick leave before the collision strongly predicted prolonged recovery following whiplash trauma. Participants with acute whiplash trauma

  6. Sick Leave within 5 Years of Whiplash Trauma Predicts Recovery: A Prospective Cohort and Register-Based Study.

    Directory of Open Access Journals (Sweden)

    Tina Birgitte Wisbech Carstensen

    Full Text Available 10-22% of individuals sustaining whiplash trauma develop persistent symptoms resulting in reduced working ability and decreased quality of life, but it is poorly understood why some people do not recover. Various collision and post-collision risk factors have been studied, but little is known about pre-collision risk factors. In particular, the impact of sickness and socioeconomic factors before the collision on recovery is sparsely explored. The aim of this study was to examine if welfare payments received within five years pre-collision predict neck pain and negative change in provisional situation one year post-collision.719 individuals with acute whiplash trauma consecutively recruited from emergency departments or primary care after car accidents in Denmark completed questionnaires on socio-demographic and health factors immediately after the collision. After 12 months, a visual analogue scale on neck pain intensity was completed. 3595 matched controls in the general population were sampled, and national public register data on social benefits and any other welfare payments were obtained for participants with acute whiplash trauma and controls from five years pre-collision to 15 months after. Participants with acute whiplash trauma who had received sickness benefit for more than 12 weeks pre-collision had increased odds for negative change in future provisional situation (Odds Ratio (OR (95% Confidence Interval (CI = 3.8 (2.1;7.1 and future neck pain (OR (95%CI = 3.3 (1.8;6.3, controlling for other known risk factors. Participants with acute whiplash trauma had weaker attachment to labour market (more weeks of sick leave (χ2(2 = 36.7, p < 0.001 and unemployment (χ2(2 = 12.5, p = 0.002 pre-collision compared with controls. Experiencing a whiplash trauma raised the odds for future negative change in provisional situation (OR (95%CI = 3.1 (2.3;4.4 compared with controls.Sick leave before the collision strongly predicted prolonged recovery

  7. Authenticated quantum secret sharing with quantum dialogue based on Bell states

    International Nuclear Information System (INIS)

    Abulkasim, Hussein; Hamad, Safwat; El Bahnasy, Khalid; Rida, Saad Z

    2016-01-01

    This work proposes a scheme that combines the advantages of a quantum secret sharing procedure and quantum dialogue. The proposed scheme enables the participants to simultaneously make mutual identity authentications, in a simulated scenario where the boss, Alice, shares a secret with her two agents Bob and Charlie. The secret is protected by checking photons to keep untrustworthy agents and outer attacks from getting useful information. Before the two agents cooperate to recover Alice’s secret, they must authenticate their identity using parts of a pre-shared key. In addition, the whole pre-shared key is reused as part of recovering the secret data to avoid any leaks of information. In comparison with previous schemes, the proposed method can efficiently detect eavesdropping and it is free from information leaks. Furthermore, the proposed scheme proved to be secure against man-in-the-middle attacks, impersonation attacks, entangled-and-measure attacks, participant attacks, modification attacks and Trojan-horse attacks. (paper)

  8. Efficient fiber-coupled single-photon sources based on quantum dots

    DEFF Research Database (Denmark)

    Daveau, Raphaël Sura

    refrigeration with coupled quantum wells. Many photonic quantum information processing applications would benet from a highbrightness, ber-coupled source of triggered single photons. This thesis presents a study of such sources based on quantum dots coupled to unidirectional photonic-crystal waveguide devices.......6 %. This latter method opens a promising future for increasing the eciency and reliability of planar chip-based single-photon sources. Refrigeration of a solid-state system with light has potential applications for cooling small-scale electronic and photonic circuits. We show theoretically that two coupled...... semiconductor quantum wells are ecient cooling media because they support long-lived indirect electron-hole pairs. These pairs can be thermally excited to distinct higher-energy states with faster radiative recombination, thereby creating an ecient escape channel to remove thermal energy from the system. From...

  9. Nanoscale phosphorus atom arrays created using STM for the fabrication of a silicon based quantum computer.

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, J. L. (Jeremy L.); Schofield, S. R. (Steven R.); Simmons, M. Y. (Michelle Y.); Clark, R. G. (Robert G.); Dzurak, A. S. (Andrew S.); Curson, N. J. (Neil J.); Kane, B. E. (Bruce E.); McAlpine, N. S. (Neal S.); Hawley, M. E. (Marilyn E.); Brown, G. W. (Geoffrey W.)

    2001-01-01

    Quantum computers offer the promise of formidable computational power for certain tasks. Of the various possible physical implementations of such a device, silicon based architectures are attractive for their scalability and ease of integration with existing silicon technology. These designs use either the electron or nuclear spin state of single donor atoms to store quantum information. Here we describe a strategy to fabricate an array of single phosphorus atoms in silicon for the construction of such a silicon based quantum computer. We demonstrate the controlled placement of single phosphorus bearing molecules on a silicon surface. This has been achieved by patterning a hydrogen mono-layer 'resist' with a scanning tunneling microscope (STM) tip and exposing the patterned surface to phosphine (PH3) molecules. We also describe preliminary studies into a process to incorporate these surface phosphorus atoms into the silicon crystal at the array sites. Keywords: Quantum computing, nanotechriology scanning turincling microscopy, hydrogen lithography

  10. Prevalence, Employment Rate, and Cost of Schizophrenia in a High-Income Welfare Society: A Population-Based Study Using Comprehensive Health and Welfare Registers.

    Science.gov (United States)

    Evensen, Stig; Wisløff, Torbjørn; Lystad, June Ullevoldsæter; Bull, Helen; Ueland, Torill; Falkum, Erik

    2016-03-01

    Schizophrenia is associated with recurrent hospitalizations, need for long-term community support, poor social functioning, and low employment rates. Despite the wide- ranging financial and social burdens associated with the illness, there is great uncertainty regarding prevalence, employment rates, and the societal costs of schizophrenia. The current study investigates 12-month prevalence of patients treated for schizophrenia, employment rates, and cost of schizophrenia using a population-based top-down approach. Data were obtained from comprehensive and mandatory health and welfare registers in Norway. We identified a 12-month prevalence of 0.17% for the entire population. The employment rate among working-age individuals was 10.24%. The societal costs for the 12-month period were USD 890 million. The average cost per individual with schizophrenia was USD 106 thousand. Inpatient care and lost productivity due to high unemployment represented 33% and 29%, respectively, of the total costs. The use of mandatory health and welfare registers enabled a unique and informative analysis on true population-based datasets. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  11. Estimation of dose to the unborn child at diagnostic X-ray examinations based on data registered in RIS/PACS

    International Nuclear Information System (INIS)

    Helmrot, Ebba; Pettersson, Haakan; Sandborg, Michael; Alten, Jonas Nilsson

    2007-01-01

    The aim of this work was to determine mean absorbed doses to the unborn child in common conventional X-ray and computed tomography (CT) examinations and to find an approach for estimating foetal dose based on data registered in the Radiological Information System/Picture Archive and Communication System (RIS/PACS). The kerma-area product (KAP) and CT dose index (CTDI vol ) in common examinations were registered using a human-shaped female dosimetry phantom. Foetal doses, D f , were measured using thermoluminescent dosimeters placed inside the phantom and compared with calculated values. Measured foetal doses were given in relation to the KAP and the CTDI vol values, respectively. Conversion factor D f /KAP varies between 0.01 and 3.8 mGy/Gycm 2 , depending on primary beam position, foetus age and beam quality (tube voltage and filtration). Conversion factors D f /CTDI vol are in the range 0.02 - 1.2 mGy/mGy, in which the foetus is outside or within the primary beam. We conclude that dose conversion factors based on KAP or CTDI vol values automatically generated by the RIS/PACS system can be used for rapid estimations of foetal dose for common examination techniques. (orig.)

  12. Federal Register in XML

    Data.gov (United States)

    National Archives and Records Administration — The Federal Register is the official daily publication for rules, proposed rules, and notices of Federal agencies and organizations, as well as executive orders and...

  13. The Danish Adoption Register.

    Science.gov (United States)

    Petersen, Liselotte; Sørensen, Thorkild I A

    2011-07-01

    The Danish Adoption Register was established in 1963-1964 to explore the genetic and environmental contribution to familial aggregation of schizophrenia. The register encompass information on all 14,425 non-familial adoptions of Danish children legally granted in Denmark 1924-1947. It includes name and date of birth of each adoptee and his or her biological and adoptive parents, date of transfer to adoptive parents and date of formal adoption. The linkage to biological and adoptive parents is close to complete, even biological fathers are registered for 91.4% of the adoptees. Adoption registers are a unique source allowing disentangling of genetic and familial environmental influences on traits, risk of diseases, and mortality.

  14. The impact of self-reported health and register-based prescription medicine purchases on re-employment chances: A prospective study.

    Science.gov (United States)

    Svane-Petersen, Annemette Coop; Dencker-Larsen, Sofie

    2016-12-01

    In this paper, we investigate the influence of self-reported health and register-based prescription medicine purchases on re-employment chances, and whether these health indicators measure similar aspects of health in this analysis. Data came from a 2006 Danish unemployment survey among a random sample of unemployed individuals enriched with register data (2006-2008, N =1806). The survey participants all received unemployment benefits from the welfare system and had been unemployed for more than 20 weeks at the time of the interview in 2006. We combined these data with longitudinal register data on individual prescription medicine purchases for somatic illnesses and prescription medicine purchases for mental illnesses, information on re-employment and various socio-demographic variables. We conducted binary logistic regression analyses to investigate the impact of self-reported health and prescription medicine purchases measured in 2006 on re-employment chances in 2007 and 2008. Our analyses show that unemployed workers with poor self-reported health and workers who had prescription medicine purchases for mental illnesses were less likely to be re-employed in 2007 and 2008. Furthermore, the impact of both prescription medicine purchases for somatic illnesses and for mental illnesses increased when adding self-reported health to the model although prescription purchases for somatic illnesses became statistically insignificant. The impact of prescription medicine purchases for somatic illnesses was mediated by self-reported health, whilst prescription medicine purchases for mental illnesses was only partly mediated. Finally, SRH seemed a much stronger prediction than prescription medicines. From these results, we propose, when possible, the inclusion of both an indicator of self-reported health and an indicator of mental health in studies on re-employment.

  15. Risk adjustment of health-care performance measures in a multinational register-based study: A pragmatic approach to a complicated topic

    Directory of Open Access Journals (Sweden)

    Tron Anders Moger

    2014-03-01

    Full Text Available Objectives: Health-care performance comparisons across countries are gaining popularity. In such comparisons, the risk adjustment methodology plays a key role for meaningful comparisons. However, comparisons may be complicated by the fact that not all participating countries are allowed to share their data across borders, meaning that only simple methods are easily used for the risk adjustment. In this study, we develop a pragmatic approach using patient-level register data from Finland, Hungary, Italy, Norway, and Sweden. Methods: Data on acute myocardial infarction patients were gathered from health-care registers in several countries. In addition to unadjusted estimates, we studied the effects of adjusting for age, gender, and a number of comorbidities. The stability of estimates for 90-day mortality and length of stay of the first hospital episode following diagnosis of acute myocardial infarction is studied graphically, using different choices of reference data. Logistic regression models are used for mortality, and negative binomial models are used for length of stay. Results: Results from the sensitivity analysis show that the various models of risk adjustment give similar results for the countries, with some exceptions for Hungary and Italy. Based on the results, in Finland and Hungary, the 90-day mortality after acute myocardial infarction is higher than in Italy, Norway, and Sweden. Conclusion: Health-care registers give encouraging possibilities to performance measurement and enable the comparison of entire patient populations between countries. Risk adjustment methodology is affected by the availability of data, and thus, the building of risk adjustment methodology must be transparent, especially when doing multinational comparative research. In that case, even basic methods of risk adjustment may still be valuable.

  16. Introduction of the second-generation direct-acting antivirals (DAAs) in chronic hepatitis C: a register-based study in Sweden.

    Science.gov (United States)

    Frisk, P; Aggefors, K; Cars, T; Feltelius, N; Loov, S A; Wettermark, B; Weiland, O

    2018-07-01

    Introduction of the direct-acting antivirals (DAAs) for treatment of chronic hepatitis C (CHC) infection has been challenging in all health systems. In Sweden, a national protocol for managed introduction was developed. It was optional, but all county councils agreed to implement and follow it. The purpose of this study was to study (a) cure rates among all patients initiated on treatment in 2014-2015, (b) prescribers' adherence to the drug recommendations and treatment eligibility criteria in the protocol, and (c) introduction rate in the six Swedish healthcare regions. A cross-sectional study where national data from the Prescribed Drug Register and the quality register InfCare Hepatitis defined the study population, and clinical data from the Patient Register and InfCare Hepatitis were used to monitor outcomes. Descriptive statistics were used. A total of 3447 patients were initiated on treatment during 2014-2015. The overall cure rate, based on data from 85% of the cohort, was 96%, with variation between genotypes. Adherence to drug recommendations increased over time and varied between 43.2 and 94.2%. Adherence to the treatment eligibility criteria was initially 80% and increased to 87% when treatment restrictions were widened. The introduction rate differed initially between the regions and reached stable levels 15-18 months after the launch of the first DAA. The estimated overall cure rate was 96%, with some variations between genotypes. A high level of adherence to the introduction protocol as well as similar introduction rates in the health care regions indicate that the introduction protocol, alongside with other measures taken, contributed considerably to a rapid uptake and equal distribution of DAAs in Sweden.

  17. Code-Based Cryptography: New Security Solutions Against a Quantum Adversary

    OpenAIRE

    Sendrier , Nicolas; Tillich , Jean-Pierre

    2016-01-01

    International audience; Cryptography is one of the key tools for providing security in our quickly evolving technological society. An adversary with the ability to use a quantum computer would defeat most of the cryptographic solutions that are deployed today to secure our communications. We do not know when quantum computing will become available, but nevertheless, the cryptographic research community must get ready for it now. Code-based cryptography is among the few cryptographic technique...

  18. Electrochemical control of quantum interference in anthraquinone-based molecular switches

    DEFF Research Database (Denmark)

    Markussen, Troels; Schiøtz, Jakob; Thygesen, Kristian Sommer

    2010-01-01

    Using first-principles calculations we analyze the electronic transport properties of a recently proposed anthraquinone-based electrochemical switch. Robust conductance on/off ratios of several orders of magnitude are observed due to destructive quantum interference present in the anthraquinone...... of hopping via the localized orbitals. The topology of the tight-binding model, which is dictated by the symmetries of the molecular orbitals, determines the amount of quantum interference....

  19. Economical multiparty simultaneous quantum identity authentication based on Greenberger–Horne–Zeilinger states

    International Nuclear Information System (INIS)

    Yu-Guang, Yang; Qiao-Yan, Wen

    2009-01-01

    A multiparty simultaneous quantum identity authentication protocol based on Greenberger–Horne–Zeilinger (GHZ) states is proposed. The multi-user can be authenticated by a trusted third party (TTP) simultaneously. Compared with the scheme proposed recently (Wang et al 2006 Chin. Phys. Lett. 23(9) 2360), the proposed scheme has the advantages of consuming fewer quantum and classical resources and lessening the difficulty and intensity of necessary operations. (general)

  20. Dependence of the modulation response of quantum dot based nanocavity devices on the number of emitters

    DEFF Research Database (Denmark)

    Lorke, Michael; Nielsen, Torben Roland; Mørk, Jesper

    2011-01-01

    A microscopic theory is used to study the dynamical properties of semiconductor quantum dot based nanocavity laser systems. The carrier kinetics and photon populations are determined using a fully quantum mechanical treatment of the light‐matter coupling. In this work, we investigate the dependency...... of the modulation response in such devices on the number of emitters coupled to the cavity mode. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)...