Miracle-dz/UniFAR-FTUs huggingface dataset:
Chaos-based Wireless Communication Resisting Multipath Effect

In additive white gaussian noise (AWGN) channel, chaos has been proved to be optimal coherent communication waveform in the sense of maximizing the signal-to-noise ratio (SNR). Recently, Lyapunov exponent spectrum of the chaotic signals after being transmitted through a wireless channel has also been proved to be unaltered, which paves the way for wireless communication using chaos. In wireless communication system, intersymbol interference (ISI) caused by multipath propagation is one of main obstacles to achieve high bit transmission rate and low bit error rate (BER). How to resist multipath effect is a fundamental problem in chaos-based wireless communication system (CWCS). In this paper, a CWCS is built by transmitting chaotic signals generated by a hybrid dynamical system and filtering the received signal using the corresponding matched filter to decrease noise effect and to detect binary information. We find that the multipath effect can be effectively resisted by regrouping the return map of received signal and setting the corresponding threshold using available information. We show that the optimal threshold is a function of the channel parameters and the transmitted information symbols. Practically, the channel parameters are time-variant, and the future information symbols are unavailable. In this case, a suboptimal threshold (SOT) is proposed, and the BER using the SOT is derived analytically. Numerical experimental results show that the CWCS achieves a very competitive performance even under inaccurate channel parameters.
Deep‐Level Comprehension of Science Texts: The Role of the Reader and the Text

Many students from elementary school through college encounter difficulty understanding their science textbooks, regardless of whether they have language disorders. This article discusses some of the particular difficulties associated with science text comprehension and possible remedies for facilitating and enhancing comprehension of challenging expository text materials. Specifically, we focus on the difficulties associated with generating inferences needed to comprehend science texts. The successful generation of inferences is affected by factors such as students' prior knowledge and reading strategies, and the manner in which science texts are written. Many students lack the necessary prior knowledge and reading strategies to generate inferences and thus comprehend science texts only poorly. Further, science texts are typically “low-cohesion” texts, which means that they require readers to generate many inferences and fill in conceptual gaps. Remedies for overcoming comprehension difficulties include matching texts to students' knowledge level and providing explicit instruction aimed at teaching students to use reading comprehension strategies for comprehension monitoring, paraphrasing, and elaborations. The computer-supported tool iSTART (Interactive Strategy Training for Active Reading and Thinking) is introduced as a technological support to assist students and teachers in the teaching/learning enterprise.
Coronal heating by the partial relaxation of twisted loops

Context: Relaxation theory offers a straightforward method for estimating the energy that is released when a magnetic field becomes unstable, as a result of continual convective driving. Aims: We present new results obtained from nonlinear magnetohydrodynamic (MHD) simulations of idealised coronal loops. The purpose of this work is to determine whether or not the simulation results agree with Taylor relaxation, which will require a modified version of relaxation theory applicable to unbounded field configurations. Methods: A three-dimensional (3D) MHD Lagrangian-remap code is used to simulate the evolution of a line-tied cylindrical coronal loop model. This model comprises three concentric layers surrounded by a potential envelope; hence, being twisted locally, each loop configuration is distinguished by a piecewise-constant current profile. Initially, all configurations carry zero-net-current fields and are in ideally unstable equilibrium. The simulation results are compared with the predictions of helicity conserving relaxation theory. Results: For all simulations, the change in helicity is no more than 2% of the initial value; also, the numerical helicities match the analytically-determined values. Magnetic energy dissipation predominantly occurs via shock heating associated with magnetic reconnection in distributed current sheets. The energy release and final field profiles produced by the numerical simulations are in agreement with the predictions given by a new model of partial relaxation theory: the relaxed field is close to a linear force free state; however, the extent of the relaxation region is limited, while the loop undergoes some radial expansion. Conclusions: The results presented here support the use of partial relaxation theory, specifically, when calculating the heating-event distributions produced by ensembles of kink-unstable loops.
Exact analysis on network capacity of airborne MANETS with digital beamforming antennas

Recently, the use of digital beamforming (DBF) antennas has been drawing lots of interest in airborne platforms for resolving the network partition problem in airborne mobile ad hoc networks (MANETs). In this paper, properties of the network capacity of an airborne MANET with DBF antennas are investigated. This paper considers an ad hoc network consisting of a number of uniformly distributed airborne platforms in a bounded area. These platforms are either directly or indirectly connected with each other through DBF antennas, and form an airborne MANET. We first formulate a digital beamforming antenna system model, referred to as the omni-direction plus sector (OPS) model, and then carry out an exact analysis for the network capacity. The OPS model characterizes the radiation pattern of a DBF antenna. Under the condition that a Hamiltonian path exists in the network, an explicit expression is derived for the network capacity. We show that, for fixed values of the OPS model, the network capacity increases as the network size increases until it reaches an optimal value. If the network size continues to increase, the network capacity will decrease until it reaches zero. Explicit expressions for the optimal network size and the maximum network capacity are also obtained. Finally, numerical results are presented. It is shown that both the optimal network size and the maximum network capacity increase as the antenna beamwidth decreases. They increase slowly when the beamwidth is large, but as the antenna beam becomes narrower, they increase faster.
Spin-Torque Noise in CPP-GMR Heads With Current Screen Layer

We investigated the head noise in current perpendicular-to-the-plane giant-magnetoresistive (CPP-GMR) heads with a current screen layer (nano oxide layer having a confined current path) to experimentally evaluate spin-torque noise in the head application. Depending on the direction/magnitude of sensing current, a significant increase in head noise was observed. Some features in noise profiles and a correlation between noise and peak asymmetry are qualitatively reasonable from the perspective of the spin-torque theory. This fact indicates that this extraordinary noise was induced by spin-transfer torque. The spin-torque noise was not observed when the heads were well biased with an orthogonal direction for the free and the reference layer, regardless of whether sensing current was positive or negative. This suggests that the spin-torque noise is not a fatal issue in current screen type CPP-GMR heads with small peak asymmetry.
Optimal micro-siting of wind turbines by genetic algorithms based on improved wind and turbine models

Micro-siting of wind turbines is a key technology for wind farm configuration. In this paper, Weibull function is used to describe the probability of wind speed distribution and turbine speed-power curve is employed to estimate turbine power generation. The improved wind and turbine models are formulated into an optimal control framework in terms of minimizing the cost per unit energy of the wind farm, which is solved by a binary-encoded genetic algorithm. Simulation results indicate that the proposed method could provide better performance and represents a more realistic and effective strategy for optimal micro-siting of the wind farm.
Palmitate-Activated Macrophages Confer Insulin Resistance to Muscle Cells by a Mechanism Involving Protein Kinase C θ and ε

Background Macrophage-derived factors contribute to whole-body insulin resistance, partly by impinging on metabolically active tissues. As proof of principle for this interaction, conditioned medium from macrophages treated with palmitate (CM-PA) reduces insulin action and glucose uptake in muscle cells. However, the mechanism whereby CM-PA confers this negative response onto muscle cells remains unknown. Methodology/Principal Findings L6-GLUT4myc myoblasts were exposed for 24 h to palmitate-free conditioned medium from RAW 264.7 macrophages pre-treated with 0.5 mM palmitate for 6 h. This palmitate-free CM-PA, containing selective cytokines and chemokines, inhibited myoblast insulin-stimulated insulin receptor substrate 1 (IRS1) tyrosine phosphorylation, AS160 phosphorylation, GLUT4 translocation and glucose uptake. These effects were accompanied by a rise in c-Jun N-terminal kinase (JNK) activation, degradation of Inhibitor of κBα (IκBα), and elevated expression of proinflammatory cytokines in myoblasts. Notably, CM-PA caused IRS1 phosphorylation on Ser1101, and phosphorylation of novel PKCθ and ε. Co-incubation of myoblasts with CM-PA and the novel and conventional PKC inhibitor Gö6983 (but not with the conventional PKC inhibitor Gö6976) prevented PKCθ and ε activation, JNK phosphorylation, restored IκBα mass and reduced proinflammatory cytokine production. Gö6983 also restored insulin signalling and glucose uptake in myoblasts. Moreover, co-silencing both novel PKC θ and ε isoforms in myoblasts by RNA interference, but not their individual silencing, prevented the inflammatory response and restored insulin sensitivity to CM-PA-treated myoblasts. Conclusions/Clinical Significance The results suggest that the block in muscle insulin action caused by CM-PA is mediated by novel PKCθ and PKCε. This study re-establishes the participation of macrophages as a relay in the action of fatty acids on muscle cells, and further identifies PKCθ and PKCε as key elements in the inflammatory and insulin resistance responses of muscle cells to macrophage products. Furthermore, it portrays these PKC isoforms as potential targets for the treatment of fatty acid-induced, inflammation-linked insulin resistance.
Genetic variation changes the interactions between the parasitic plant-ecosystem engineer Rhinanthus and its hosts

Within-species genetic variation is a potent factor influencing between-species interactions and community-level structure. Species of the hemi-parasitic plant genus Rhinanthus act as ecosystem engineers, significantly altering above- and below-ground community structure in grasslands. Here, we show the importance of genotypic variation within a single host species (barley—Hordeum vulgare), and population-level variation among two species of parasite (Rhinanthus minor and Rhinanthus angustifolius) on the outcome of parasite infection for both partners. We measured host fitness (number of seeds) and calculated parasite virulence as the difference in seed set between infected and uninfected hosts (the inverse of host tolerance). Virulence was determined by genetic variation within the host species and among the parasite species, but R. angustifolius was consistently more virulent than R. minor. The most tolerant host had the lowest inherent fitness and did not gain a fitness advantage over other infected hosts. We measured parasite size as a proxy for transmission ability (ability to infect further hosts) and host resistance. Parasite size depended on the specific combination of host genotype, parasite species and parasite population, and no species was consistently larger. We demonstrate that the outcome of infection by Rhinanthus depends not only on the host species, but also on the underlying genetics of both host and parasite. Thus, genetic variations within host and parasite are probably essential components of the ecosystem-altering effects of Rhinanthus.
Performativity by stealth: a critique of recent initiatives on creativity

This article offers an analysis of recent development in primary education, in particular the prevailing climate of performativity and new initiatives on creativity. Since 1989 education has been dominated by the performativity discourse accompanied by the obsession with evidence: of children's learning; of teachers' performance; and of student teachers' ‘covering’ the standards. Recent initiatives would seem to signify a shift in official Government thinking on education and a move to embrace the creativity discourse. The commissioning of a national report on creativity and culture was an important first step. There was also the QCA's literature review of creativity, and the development of the QCA web site on creativity. More recently, we have seen the introduction of the new Primary National Strategy (PNS) via the DfES document Excellence and Enjoyment and Government support for creative partnerships: a programme aimed at developing creativity in learning and participation in cultural activities. This article argues that the new initiatives on creativity do not herald major change in primary education. It offers a critique of two significant texts: the Primary National Strategy and the QCA web site on creativity. It presents an alternative analysis of creativity and suggests ways forward to prevent creativity becoming hijacked by the performativity discourse.
The soft X-ray spectrum from NGC 1068 observed with LETGS on Chandra

Using the combined spectral and spatial resolving power of the Low Energy Transmission Grating (LETGS) on board Chandra, we obtain separate spectra from the bright central source of NGC 1068 (Primary region), and from a fainter bright spot 4” to the NE (Secondary region). Both spectra are dominated by discrete line emission from H- and He-like ions of C through S, and from Fe L-shell ions, but also include narrow radiative recombination continua (RRC), indicating that most of the observed soft X-ray emission arises in low-temperature (kT_e ~ few eV) photoionized plasma. We confirm the conclusions of Kinkhabwala et al. ([CITE]), based on XMM-Newton Reflection Grating Spectrometer (RGS) observations, that the entire nuclear spectrum can be explained by recombination/radiative cascade following photoionization, and radiative decay following photoexcitation, with no evidence for the presence of hot, collisionally ionized plasma. In addition, we show that this same model also provides an excellent fit to the spectrum of the Secondary region, albeit with radial column densities roughly a factor of three lower, as would be expected given its distance from the source of the ionizing continuum. The remarkable overlap and kinematical agreement of the optical and X-ray line emission, coupled with the need for a distribution of ionization parameter to explain the X-ray spectra, collectively imply the presence of a distribution of densities (over a few orders of magnitude) at each radius in the ionization cone. Relative abundances of all elements are consistent with Solar abundance, except for N, which is 2–3 times Solar. Finally, the long wavelength spectrum beyond 30 A is rich of L-shell transitions of Mg, Si, S, and Ar, and M-shell transitions of Fe. The velocity dispersion decreases with increasing ionization parameter, which has been deduced from the measured line intensities of particularly these long wavelength lines in conjunction with the Fe-L shell lines.
Human pose fusion for scalable kinetic interfaces

In this paper we present a method for fusion of human poses that are estimated simultaneously from multiple RGB-D cameras. The proposed solution is scalable in terms of the number of used sensors, processing power, network overhead and keeping latency within small temporal bounds. Spatial relations of cameras are continuously estimated in near real-time from the acquired data. Sensors can be added, removed or repositioned without significant disruption of the systems functioning.
Algebraic K-theory of von Neumann algebras

To every von Neumann algebra one can associate a (multiplicative) determinant defined on the invertible elements of the algebra with range a subgroup of the abelian group of the invertible elements of the center of the von Neumann algebra. This determinant is a normalization of the usual determinant for finite von Neumann algebras of type I, for the type II1-case it is the Fuglede-Kadison determinant, and for properly infinite von Neumann algebras the determinant is constant equal to 1. It is proved that every invertible element of determinant 1 is a product of a finite number of commutators. This extends a result of T. Fack and P. de la Harpe for II1-factors. As a corollary it follows that the determinant induces an injection from the algebraic K1-group of the von Neumann algebra into the abelian group of the invertible elements of the center. Its image is described. Another group, Kw 1 (A), which is generated by elements in matrix algebras over A that induce injective right multiplication maps is also computed. We use the Fuglede-Kadison determinant to detect elements in the Whitehead group Wh(G). ∗Partially supported by NSF Grant DMS 9103327
Spectrally efficient fronthaul architectures for a cost-effective 5G C-RAN

In 5G wireless systems, centralized RAN (C-RAN) is an architectural choice where the signal waveforms received by Remote Radio Heads (RRH) are transparently forwarded to base band units (BBU), in many cases using an optical fronthaul. Although C-RAN highly simplifies the RRH, which is positive from the operational cost standpoint, much of the system complexity and cost is shifted towards the optical fronthaul. In this paper we show how a cost-effective C-RAN requires a spectrally-efficient optical fronthaul, and discuss the technological options to realize it.
Identification of Genes Differentially Expressed in Extraradical Mycelium and Ectomycorrhizal Roots during Paxillus involutus-Betula pendula Ectomycorrhizal Symbiosis

ABSTRACT The development of ectomycorrhizal symbiosis leads to drastic changes in gene expression in both partners. However, little is known about the spatial regulation of symbiosis-regulated genes. Using cDNA array profiling, we compared the levels of expression of fungal genes corresponding to approximately 1,200 expressed sequenced tags in the ectomycorrhizal root tips (ECM) and the connected extraradical mycelium (EM) for the Paxillus involutus-Betula pendula ectomycorrhizal association grown on peat in a microcosm system. Sixty-five unique genes were found to be differentially expressed in these two fungal compartments. In ECM, a gene coding for a putative phosphatidylserine decarboxylase (Psd) was up-regulated by 24-fold, while genes coding for urea (Dur3) and spermine (Tpo3) transporters were up-regulated 4.1- and 6.2-fold in EM. Moreover, urea was the major nitrogen compound found in EM by gas chromatography-mass spectrometry analysis. These results suggest that (i) there is a spatial difference in the patterns of fungal gene expression between ECM and EM, (ii) urea and polyamine transporters could facilitate the translocation of nitrogen compounds within the EM network, and (iii) fungal Psd may contribute to membrane remodeling during ectomycorrhiza formation.
Plan B Project for Master in Statistics : The Effect of Farming Practices on Changes in Soil Organic Carbon and Nitrogen

The amount of organic carbon and nitrogen stored in the soil are thought to be related to climate change. This collaboration with researchers from the Department of Soil, Water, and Climate investigated the effects of farming practices on changes in soil organic carbon and nitrogen. Specifically, the effects of irrigation systems and the amount of manure applied were studied using soil samples collected from Fall 2006 to Fall 2013 at 98 GPS-registered sites at a large dairy in Western Minnesota. Since the data involved repeated measures over time as well as potential correlation between nearby sites, several mixed models were fit to investigate the correlation structures within individual sites between years and also the spatial correlation between sites. Results were qualitatively similar between models, but model selection procedures and information about the nature of the data were used to assess the results of the analyses and possible limitations.
The Polidoxa Shift: a New Approach to Social Networks

Access to global information is of primary importance in a global world. The Internet contains a huge amount of documents and it has a big potential as a news media, but the key is in the mechanism in which information is accessed. This paper describes a novel idea consisting in combining the potential of both social networks and search engines. We describe here the basic ideas behind a trust ranking algorithm based on the activities and networking performed by users on a social network. We motivate the need for Polidoxa, the combined social network and search engine, and we finally describe the advantages over traditional media, traditional search engine like Google and social network such as Facebook. © 2011 Newcastle University. Printed and published by Newcastle University, Computing Science, Claremont Tower, Claremont Road, Newcastle upon Tyne, NE1 7RU, England. Bibliographical details MAZZARA, M. , MARRAFFA, A. , BISELLI, L. , CHIARABINI, L. , The Polidoxa Shift: a New Approach to Social Networks [By] M. Mazzara, A. Marraffa, L. Biselli, L. Chiarabini Newcastle upon Tyne: Newcastle University: Computing Science, 2011. (Newcastle University, Computing Science, Technical Report Series, No. CS-TR-1275)
A study of Vermeer

Edward Snow's "A Study of Vermeer", first published in 1979 and here presented in an expanded and elaborately revised version, starts from a single premise: that we respond so intensely to Vermeer because his paintings reach so deeply into our lives. Our desire for images, the distances that separate us, the validations we seek from the still world, the traces of ghostliness in our own human presence - these, the book proposes, are Vermeer's themes, which he pursues with a realism always in touch with the uncanny. As Snow traces the many counterpoised sensations that make up Vermeer's equanimity, he leads us into a world of nuances and surprise. "A Study of Vermeer" is passionate and visual in its commitments. Snow works from the conviction that viewing pictures is a reciprocal act - symbiotic, consequential, real. His discussions of Vermeer's paintings are conducted in a language of patient observation, and they involve the reader in an experience of deepening relation and ongoing visual discovery. The book has been designed to facilitate this process: over eighty illustrations, fifty-nine in color (including two full-page foldouts), accompany the text so that the details Snow illuminates will be continually in view. Here is a book to enthrall not only students of Vermeer, but anyone who feels the exhilaration of what Cezanne called 'thinking in images. '