Global Dynamics of Higher-Order Transcendental-Type Generalized Beverton–Holt Equations

We investigate generalized Beverton–Holt difference equations of order k

An Efficient Threshold Access-Structure for RLWE-Based Multiparty Homomorphic Encryption

We propose and implement a multiparty homomorphic encryption (MHE) scheme with a $t$-out-of-$N$-threshold access-structure that is efficient and does not require a trusted dealer in the common random-string model. We construct this scheme from the ring-learning-with-error (RLWE) assumptions, and as an extension of the MHE scheme of Mouchet et al. (PETS 21). By means of a specially adapted share re-sharing procedure, this extension can be used to relax the $N$-out-of-$N$-threshold access structure of the original scheme into a $t$-out-of-$N$-threshold one. This procedure introduces only a single round of communication during the setup phase, after which any set of at least $t$ parties can compute a $t$-out-of-$t$ additive sharing of the secret key with no interaction; this new sharing can be used directly in the scheme of Mouchet et al. We show that, by performing Shamir re-sharing over the MHE ciphertext-space ring with a carefully chosen exceptional set, this reconstruction procedure can be made secure and has negligible overhead. Moreover, it only requires the parties to store a constant-size state after its setup phase. Hence, in addition to fault tolerance, lowering the corruption threshold also yields considerable efficiency benefits, by enabling the distribution of batched secret-key operations among the online parties. We implemented and open-sourced our scheme in the Lattigo library

Active noise control over adaptive distributed networks

© 2015. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/This paper presents the implementation of Active Noise Control (ANC) systems over a network of distributed acoustic nodes. For this purpose we define a general acoustic node consisting of one or several microphones and one or several loudspeakers together with a unique processor with communication capabilities. ANC systems can use a wide range of adaptive algorithms, but we have considered specifically the Multiple Error Filtered-x Least Mean Square (MEFxLMS), which has been proved to perform very well for ANC systems with multiple microphones and loudspeakers, and centralized processing. We present a new formulation to introduce the distributed version of the MEFxLMS together with an incremental collaborative strategy in the network. We demonstrate that the distributed MEFxLMS exhibits the same performance as the centralized one when there are no communication constraints in the network. Then, we re-formulate the distributed MEFxLMS to include parameters related to its implementation on an acoustic sensor network: latency of the network, computational capacity of the nodes, and trustworthiness of the signals measured at each node. Simulation results in realistic scenarios show the ability of the proposed distributed algorithms to achieve good performance when proper values of these parameters are chosen. (C) 2014 Elsevier B.V. All rights reserved.This work has been supported by European Union ERDF and Spanish Government through TEC2012-38142-C04 Project, and Generalitat Valenciana through PROMETEOII/2014/003 Project.Ferrer Contreras, M.; Diego Antón, MD.; Piñero Sipán, MG.; González Salvador, A. (2015). Active noise control over adaptive distributed networks. Signal Processing. 107:82-95. https://doi.org/10.1016/j.sigpro.2014.07.026S829510

T. brucei cathepsin-L increases arrhythmogenic sarcoplasmic reticulum-mediated calcium release in rat cardiomyocytes

Aims: African trypanosomiasis, caused by Trypanosoma brucei species, leads to both neurological and cardiac dysfunction and can be fatal if untreated. While the neurological-related pathogenesis is well studied, the cardiac pathogenesis remains unknown. The current study exposed isolated ventricular cardiomyocytes and adult rat hearts to T. brucei to test whether trypanosomes can alter cardiac function independent of a systemic inflammatory/immune response. Methods and results: Using confocal imaging, T. brucei and T. brucei culture media (supernatant) caused an increased frequency of arrhythmogenic spontaneous diastolic sarcoplasmic reticulum (SR)-mediated Ca2+ release (Ca2+ waves) in isolated adult rat ventricular cardiomyocytes. Studies utilising inhibitors, recombinant protein and RNAi all demonstrated that this altered SR function was due to T. brucei cathepsin-L (TbCatL). Separate experiments revealed that TbCatL induced a 10–15% increase of SERCA activity but reduced SR Ca2+ content, suggesting a concomitant increased SR-mediated Ca2+ leak. This conclusion was supported by data demonstrating that TbCatL increased Ca2+ wave frequency. These effects were abolished by autocamtide-2-related inhibitory peptide, highlighting a role for CaMKII in the TbCatL action on SR function. Isolated Langendorff perfused whole heart experiments confirmed that supernatant caused an increased number of arrhythmic events. Conclusion: These data demonstrate for the first time that African trypanosomes alter cardiac function independent of a systemic immune response, via a mechanism involving extracellular cathepsin-L-mediated changes in SR function

Management of Delayed Onset Postoperative Hemorrhage after Anastomotic Urethroplasty

Excision with primary anastomosis (EPA) urethroplasty is generally the preferred method for short strictures in the bulbar urethra, given its high success rate and low complication rate compared to other surgical interventions. Bleeding is a presumed risk factor for any surgical procedure but perioperative hemorrhage after an EPA requiring hospitalization and/or reintervention is unreported with no known consensus on the best course for management. Through our experience with three separate cases of significant postoperative urethral hemorrhage after EPA, we developed an algorithm for treatment beginning with conservative management and progressing through endoscopic and open techniques, as well as consideration of embolization by interventional radiology. All the three of these cases were managed successfully though they did require multiple interventions. We theorize that younger patients with more robust corpus spongiosum and more vigorous spontaneous erections, patients that have undergone fewer prior urethral procedures and therefore have more prominent vasculature, and those patients managed with a two-layer closure of the ventral urethra without ligation of the transected bulbar arteries are at a higher risk for this complication

Journalism ethics in a digital environment: How journalistic codes of ethics have been adapted to the Internet and ICTs in countries around the world

Journalism is facing new ethical issues because of the emergence of the Internet and Information and Communication Technologies (ICTs). In this article, we examine how journalistic codes of ethics have been updated to address this new reality. Three research questions are explored through a systematic analysis of 99 codes from around the world. Results show that, of the 99 codes analyzed, only 9 include references to the Internet and ICTs. We conclude with proposals for changes in the codes that would help journalists resolve these new moral issues

Structure of strontium tellurite glass, anti-glass and crystalline phases by high-energy X-ray diffraction, reverse Monte Carlo and Rietveld analysis

The structures of xSrO–(100 _ x)TeO2 (x = 5, 7.5, 8.5 and 10 mol.%) glass, antiglass and crystalline samples were studied by high-energy X-ray diffraction (HEXRD), reverse Monte Carlo (RMC) simulations, atomic pair distribution function analysis and Fullprof Rietveld refinement. The atomic pair distributions show the first peak at 1.90 A ˚ due to the Te—O equatorial bonds and the Te—O peak is asymmetrical due to the range of Te—O bond lengths in glass, anti-glass and crystalline samples. The short-range structural properties of glasses such as Te—O bond lengths, Te–O speciation, Te–Te distances and O— Te—O bond angle distributions were determined by RMC simulations. The average Te–O coordination number (NTe–O) for 5SrO–95TeO2 glass is 3.93 which decreases to 3.59 on increasing the SrO concentration to 10 mol.%. The changes in NTe–O revealed that the glass network predominantly contains TeO4 units with a small amount of TeO3 units and there is a structural transformation TeO4 ! TeO3 with an increase in SrO concentration. The O—Te—O bond angle distributions have a peak at 79_ and reveal that the Oequatorial—Te—Oequatorial bonds are the most abundant linkages in the tellurite network. Two glass samples containing 7.5 and 8.5 mol.% of SrO were annealed at 350_C for 1 h to produce anti-glass phases; they were further annealed at 450_C for 4 h to transform them into crystalline phases. The anti-glass samples are disordered cubic SrTe5O11 and the disordered monoclinic SrTeO3 phases, whereas the crystalline samples contain monoclinic SrTeO3 and the orthorhombic TeO2 phases. The unit-cell parameters of the anti-glass and crystalline structures were determined by Fullprof Rietveld refinement. Thermal studies found that the glass transition temperature increases with an increase in SrO mol.% and the results on the short-range structure of glasses from Raman spectroscopy are in agreement with the RMC findings.Funding for this research was provided by: Inter University Accelerator Centre, New Delhi, UGC-DAE Consortium for Scientific Research, University Grants Commission, Mumbai. Financial support by the Department of Science and Technology (Government of India) provided within the framework of the India @DESY collaboration is gratefully acknowledged

Results of the MAJORANA DEMONSTRATOR's Search for Double-Beta Decay of 76Ge to Excited States of 76Se

The MAJORANA DEMONSTRATOR is searching for double-beta decay of 76Ge to excited states (E.S.) in 76Se using a modular array of high purity Germanium detectors. 76Ge can decay into three E.S.s of 76Se. The E.S. decays have a clear event signature consisting of a ββ-decay with the prompt emission of one or two γ-rays, resulting in with high probability in a multi-site event. The granularity of the DEMONSTRATOR detector array enables powerful discrimination of this event signature from backgrounds. Using 21.3 kg-y of isotopic exposure, the DEMONSTRATOR has set world leading limits for each E.S. decay, with 90% CL lower half-life limits in the range of (0.56 2.1) ⋅ 1024 y. In particular, for the 2v transition to the first 0+ E.S. of 76Se, a lower half-life limit of 0.68 ⋅ 1024 at 90% CL was achieved

ADC Nonlinearity Correction for the Majorana Demonstrator

Imperfections in analog-to-digital conversion (ADC) cannot be ignored when signal digitization requirements demand both wide dynamic range and high resolution, as is the case for the Majorana Demonstrator 76Ge neutrinoless double-beta decay search. Enabling the experiment's high-resolution spectral analysis and efficient pulse shape discrimination required careful measurement and correction of ADC nonlinearities. A simple measurement protocol was developed that did not require sophisticated equipment or lengthy data-taking campaigns. A slope-dependent hysteresis was observed and characterized. A correction applied to digitized waveforms prior to signal processing reduced the differential and integral nonlinearities by an order of magnitude, eliminating these as dominant contributions to the systematic energy uncertainty at the double-beta decay Q value