Miracle-dz/UniFAR-FTUs huggingface dataset:
Differential Space-Frequency Modulation and Fast 2-D Multiple-Symbol Differential Detection for MIMO-OFDM

The combination of differential space-frequency modulation (DSFM) with orthogonal frequency-division multiplexing (OFDM) is attractive for transmission over time-and frequency-selective multiple-input-multiple-output (MIMO) channels and detection without the need for channel-state information (CSI) at the receiver. It is well known that a simple differential detection already results in a high error floor for moderate time and frequency selectivities of the channel. A more sophisticated multiple-symbol differential detection (MSDD), which jointly processes multiple received symbols, overcomes this limitation, usually at the price of higher detection complexity. In this paper, we consider the DSFM for the MIMO-OFDM transmission and MSDD at the receiver. Inspired by previous work presented in literature, we devise a novel DSFM scheme, which makes use of spatial and/or spectral (multipath) diversity and is particularly suited for the MIMO-OFDM and power-efficient low-delay MSDD. We further investigate the application of a 2-D observation window to the MSDD (2-D MSDD) in order to exploit channel correlations in both time and frequency directions. We develop a representation of the detection problem that is amenable to tree-search decoding, whose application leads to a tremendous reduction in the MSDD complexity or a "fast" MSDD. An analytical approximation of the symbol-error rate of the 2-D MSDD for the MIMO-OFDM under spatially correlated fading is derived, which enables quick and accurate performance evaluations. Numerical and simulation results corroborate the efficacy of our approach and show that power efficiency close to that of a coherent detection with a perfect CSI is feasible in all standard fading scenarios at reasonable decoder complexity.
Back to the Future: The Role of Possible Selves in Developing a Physical Activity Identity in Newly Retired Individuals

Retirement is not always associated with increased physical activity. We examined the interrelationships between two physical activity self-perceptions identity and possible selves and physical activity in 548 new retirees. The aims were to understand why retirement coalesces with increased physical activity for some but not all retirees and inform future interventions. Crosssectional data were collected via online questionnaire. Identity and possible selves were related to physical activity. Moreover, we found positive associations between possible selves focused on physical activity and physical activity identity. Our findings on self-perceptions represent an important first step toward designing relevant physical activity interventions for retirees.
Learning to predict super resolution wavelet coefficients

We develop a wavelet domain learning based technique for single image super resolution (SISR). First, we learn a mapping between a patch of approximate coefficients (ACs) and the detail coefficients (DCs) corresponding the center location of the patch using Neural Networks. We then obtain an SR image by using an approximate version of the original image (scaled as per the DWT size requirements of the final image) as ACs and by predicting the corresponding DCs using the mapping thus learnt. Our results compare favorably to both mature techniques and state of the art other learning based techniques.
Coherence analysis of iterative thresholding algorithms

There is a recent surge of interest in developing algorithms for finding sparse solutions of underdetermined systems of linear equations y = Φχ. In many applications, extremely large problem sizes are envisioned, with at least tens of thousands of equations and hundreds of thousands of unknowns. For such problem sizes, low computational complexity is paramount. The best studied l1 minimization algorithm is not fast enough to fulfill this need. Iterative thresholding algorithms have been proposed to address this problem. In this paper we want to analyze three of these algorithms theoretically, and give sufficient conditions under which they recover the sparsest solution.
Technological Advance in Cooling Systems at U.S. Power Plants

Prior to adoption of the 1972 Clean Water Act (CWA) most U.S. power plants used once-through cooling water systems that discharged large quantities of warm water. This resulted in significant amounts of thermal pollution in neighboring bodies of water. The CWA essentially mandated recirculating systems for new facilities. This paper investigates whether there was technological advance in cooling systems, which we define as reductions in performance-adjusted costs, and how these advances are related to imposition of the CWA. Results suggest that the performance-adjusted cost of installing a recirculating cooling system was falling prior to implementation of the CWA but rose thereafter. This is consistent with the theoretical work suggesting that command and control regulation offers poor incentives for advances in pollution control technology.
Automatic control of tethered wings for airborne wind energy: Design and experimental results

A new approach to control tethered wings for airborne wind energy is described. A fixed length of the lines is considered, and the aim of the control system is to obtain figure-eight crosswind trajectories. The proposed technique is based on the notion of the wing's “velocity angle” and, in contrast with most existing approaches, it does not require a measurement of the wind speed or of the effective wind at the wing's location. Moreover, the proposed approach features few parameters, whose effects on the system's behavior are very intuitive, hence simplifying tuning procedures. Experimental results are presented, obtained by extensively testing the approach with a small-scale prototype.
Haemophilus influenzae Serotype a Invasive Disease, Alaska, USA, 1983–2011

Before introduction of Haemophilus influenzae type b (Hib) vaccines, rates of Hib disease in Alaska’s indigenous people were among the highest in the world. Vaccination reduced rates dramatically; however, invasive H. influenzae type a (Hia) disease has emerged. Cases of invasive disease were identified through Alaska statewide surveillance during1983–2011. Of 866 isolates analyzed for serotype, 32 (4%) were Hia. No Hia disease was identified before 2002; 32 cases occurred during 2002–2011 (p<0.001). Median age of case-patients was 0.7 years; 3 infants died. Incidence of Hia infection (2002–2011) among children <5 years was 5.4/100,000; 27 cases occurred in Alaska Native children (18/100,000) versus 2 cases in non-Native children (0.5/100,000) (risk ratio = 36, p<0.001). From 12/2009 to 12/2011, 15 cases of Hia disease occurred in southwestern Alaska (in children <5 years, rate = 204/100,000). Since introduction of the Hib conjugate vaccine, Hia infection has become a major invasive bacterial disease in Alaska Native children.
Spike Timing and Reliability in Cortical Pyramidal Neurons: Effects of EPSC Kinetics, Input Synchronization and Background Noise on Spike Timing

In vivo studies have shown that neurons in the neocortex can generate action potentials at high temporal precision. The mechanisms controlling timing and reliability of action potential generation in neocortical neurons, however, are still poorly understood. Here we investigated the temporal precision and reliability of spike firing in cortical layer V pyramidal cells at near-threshold membrane potentials. Timing and reliability of spike responses were a function of EPSC kinetics, temporal jitter of population excitatory inputs, and of background synaptic noise. We used somatic current injection to mimic population synaptic input events and measured spike probability and spike time precision (STP), the latter defined as the time window (Δt) holding 80% of response spikes. EPSC rise and decay times were varied over the known physiological spectrum. At spike threshold level, EPSC decay time had a stronger influence on STP than rise time. Generally, STP was highest (≤2.45 ms) in response to synchronous compounds of EPSCs with fast rise and decay kinetics. Compounds with slow EPSC kinetics (decay time constants>6 ms) triggered spikes at lower temporal precision (≥6.58 ms). We found an overall linear relationship between STP and spike delay. The difference in STP between fast and slow compound EPSCs could be reduced by incrementing the amplitude of slow compound EPSCs. The introduction of a temporal jitter to compound EPSCs had a comparatively small effect on STP, with a tenfold increase in jitter resulting in only a five fold decrease in STP. In the presence of simulated synaptic background activity, precisely timed spikes could still be induced by fast EPSCs, but not by slow EPSCs.
The formation and gas content of high-redshift galaxies and minihaloes

We investigate the suppression of the baryon density fluctuations compared to the dark matter in the linear regime. Previous calculations predict that the suppression occurs up to a characteristic mass scale of ∼10 6 M ⊙ , which suggests that pressure has a central role in determining the properties of the first luminous objects at early times. We show that the expected characteristic mass scale is in fact substantially lower (by a factor of ∼3-10, depending on redshift), and thus the effect of baryonic pressure on the formation of galaxies up to reionization is only moderate. This reduction in the characteristic mass scale is a result of including the fact that the baryons have smoother initial conditions than the dark matter. This smoothing is due to the aftereffects of the coupling with the radiation before recombination. This yields lower pressure gradients than previous estimations in the period from cosmic recombination to z ∼ 200, after which the gas cooled down adiabatically and the pressure dropped. At z ∼ 10 the suppression of the baryon fluctuations is still sensitive to the history of pressure in this high-redshift era. We calculate the fraction of the cosmic gas that is in minihaloes and find that it is substantially higher than would be expected with the previously estimated characteristic mass. Expanding our investigation to the non-linear regime, we calculate in detail the spherical collapse of high-redshift objects in a A cold dark matter universe. We include the gravitational contributions of the baryons and radiation and the memory of their kinematic coupling before recombination. We use our results to predict a more accurate halo mass function as a function of redshift.
Testing Neoclassical Competitive Theory in Multilateral Decentralized Markets

Walrasian tâtonnement has been a fundamental assumption in economics ever since Walras’ general equilibrium theory was introduced in 1874. Nearly a century after its introduction, Vernon Smith relaxed the Walrasian tâtonnement assumption by showing that neoclassical competitive market theory explains the equilibrating forces in “double‐auction” markets. I make a next step in this evolution by exploring the predictive power of neoclassical theory in decentralized naturally occurring markets. Using data gathered from two distinct markets—the sports card and collector pin markets—I find a tendency for exchange prices to approach the neoclassical competitive model prediction after a few market periods.
Phenylxylylethane (PXE): a high-density, high-flashpoint organic liquid scintillator for applications in low-energy particle and astrophysics experiments

We report on the study of a new liquid scintillator target for neutrino interactions in the framework of the research and development program of the Borexino solar neutrino experiment. The scintillator consists of 1,2–dimethyl–4–(1–phenylethyl)– benzene (phenyl–o–xylylethane, PXE) as solvent and 1,4-diphenylbenzene (para-Terphenyl, p-Tp) as primary and 1,4-bis(2-methylstyryl)benzene (bis-MSB) as secondary solute. The density close to that of water and the high ﬂash point makes it an attractive option for large scintillation detectors in general. The study focused on optical properties, radioactive trace impurities and novel puriﬁcation techniques of the scintillator. Attenuation lengths of the scintillator mixture of 12 m at 430 nm were achieved after puriﬁcation with an alumina column. A radio carbon isotopic ratio of 14 C / 12 C = 9 . 1 × 10 − 18 has been measured in the scintillator. Initial trace impurities, e.g. 238 U at 3 . 2 × 10 − 14 g/g could be puriﬁed to levels below 1 × 10 − 17 g/g by silica gel solid column puriﬁcation.
Decomposition by partial linearization in multiuser systems

We propose a decomposition framework for the distributed optimization of general nonconvex sum-utility functions arising in the design of wireless multi-user interfering systems. Our main contributions are: the development of the first provably convergent Jacobi best-response algorithm, where all users simultaneously solve a suitably convexified version of the original sum-utility optimization problem; the derivation of a general dynamic pricing mechanism that provides a unified view of existing pricing schemes that are based, instead, on heuristics; and a framework that can be easily particularized to well-known applications, giving rise to practical algorithms that outperform all existing ad-hoc methods proposed for very specific problems. Our framework contains as special cases well-known gradient algorithms for nonconvex sum-utility problems, and many block-coordinate descents schemes for convex functions.
Self–adjoint time operator is the rule for discrete semi–bounded Hamiltonians

We prove explicitly that to every discrete semi–bounded Hamiltonian with constant degeneracy, and with a finite sum of the squares of the reciprocal of its eigenvalues and whose eigenvectors span the entire Hilbert space, there exists a characteristic self–adjoint time operator that is canonically conjugate to the Hamiltonian in a dense subspace of the Hilbert space. Moreover, we show that each characteristic time operator generates an uncountable class of self–adjoint operators canonically conjugate to the same Hamiltonian in the same dense subspace.
Ty3 Retrotransposon Hijacks Mating Yeast RNA Processing Bodies to Infect New Genomes

Retrotransposition of the budding yeast long terminal repeat retrotransposon Ty3 is activated during mating. In this study, proteins that associate with Ty3 Gag3 capsid protein during virus-like particle (VLP) assembly were identified by mass spectrometry and screened for roles in mating-stimulated retrotransposition. Components of RNA processing bodies including DEAD box helicases Dhh1/DDX6 and Ded1/DDX3, Sm-like protein Lsm1, decapping protein Dcp2, and 5’ to 3’ exonuclease Xrn1 were among the proteins identified. These proteins associated with Ty3 proteins and RNA, and were required for formation of Ty3 VLP retrosome assembly factories and for retrotransposition. Specifically, Dhh1/DDX6 was required for normal levels of Ty3 genomic RNA, and Lsm1 and Xrn1 were required for association of Ty3 protein and RNA into retrosomes. This role for components of RNA processing bodies in promoting VLP assembly and retrotransposition during mating in a yeast that lacks RNA interference, contrasts with roles proposed for orthologous components in animal germ cell ribonucleoprotein granules in turnover and epigenetic suppression of retrotransposon RNAs.
A Load/Store Unit for a Memcpy Hardware Accelerator

Recently, a dedicated hardware accelerator was proposed that works in conjunction with caches found next to modern-day microprocessors, to speedup the commonly utilized memcpy operation. The main assumption of the proposal was that the to-be-memcpy-ed data has to reside inside the cache, which is not always valid. In this paper, we present a dedicated load/store unit and its implementation which cooperates with the previously proposed memcpy hardware accelerator and cache to ensure that data becomes available in the cache. Experimental results, using synthetic benchmarks, show that the load/store unit in conjunction with the memcpy hardware accelerator is capable of reducing the memcpy latencies by 85% (when the data is not present in the cache) compared to a highly optimized, hand-coded in assembly software solution.
The nature of galaxy bias and clustering

We have used a combination of high resolution cosmological N-body simulations and semi-analytic modelling of galaxy formation to investigate the processes that determine the spatial distribution of galaxies in cold dark matter (CDM) models and its relation to the spatial distribution of dark matter. The galaxy distribution depends sensitively on the efficiency with which galaxies form in haloes of different mass. In small mass haloes, galaxy formation is inhibited by the reheating of cooled gas by feedback processes, whereas in large mass haloes, it is inhibited by the long cooling time of the gas. As a result, the mass-to-light ratio of haloes has a deep minimum at the halo mass, ∼1012 M⊙, associated with L* galaxies, where galaxy formation is most efficient. This dependence of galaxy formation efficiency on halo mass leads to a scale-dependent bias in the distribution of galaxies relative to the distribution of mass. On large scales, the bias in the galaxy distribution is related in a simple way to the bias in the distribution of massive haloes. On small scales, the correlation function is determined by the interplay between various effects including the spatial exclusion of dark matter haloes, the distribution function of the number of galaxies occupying a single dark matter halo and, to a lesser extent, dynamical friction. Remarkably, these processes conspire to produce a correlation function in a flat, Ω0=0.3, CDM model that is close to a power law over nearly four orders of magnitude in amplitude. This model agrees well with the correlation function of galaxies measured in the automated-plate measurement survey. On small scales, the model galaxies are less strongly clustered than the dark matter, whereas on large scales they trace the occupied haloes. Our clustering predictions are robust to changes in the parameters of the galaxy formation model, provided only those models which match the bright end of the galaxy luminosity function are considered.
The Functional Interaction between Acyl-CoA Synthetase 4, 5-Lipooxygenase and Cyclooxygenase-2 Controls Tumor Growth: A Novel Therapeutic Target

The acyl-CoA synthetase 4 (ACSL4), which esterify mainly arachidonic acid (AA) into acyl-CoA, is increased in breast, colon and hepatocellular carcinoma. The transfection of MCF-7 cells with ACSL4 cDNA transforms the cells into a highly aggressive phenotype and controls both lipooxygenase-5 (LOX-5) and cyclooxygenase-2 (COX-2) metabolism of AA, suggesting a causal role of ACSL4 in tumorigenesis. We hypothesized that ACSL4, LOX-5 and COX-2 may constitute potential therapeutic targets for the control of tumor growth. Therefore, the aim of this study was to use a tetracycline Tet-Off system of MCF-7 xenograft model of breast cancer to confirm the effect of ACSL4 overexpression on tumor growth in vivo. We also aim to determine whether a combinatorial inhibition of the ACSL4-LOX-COX-2 pathway affects tumor growth in vivo using a xenograft model based on MDA-MB-231 cells, a highly aggressive breast cancer cell line naturally overexpressing ACSL4. The first novel finding is that stable transfection of MCF-7 cells with ACSL4 using the tetracycline Tet-Off system of MCF-7 cells resulted in development of growing tumors when injected into nude mice. Tumor xenograft development measured in animals that received doxycycline resulted in tumor growth inhibition. The tumors presented marked nuclear polymorphism, high mitotic index and low expression of estrogen and progesterone receptor. These results demonstrate the transformational capacity of ACSL4 overexpression. We examined the effect of a combination of inhibitors of ACSL4, LOX-5 and COX-2 on MDA-MB-231 tumor xenografts. This treatment markedly reduced tumor growth in doses of these inhibitors that were otherwise ineffective when used alone, indicating a synergistic effect of the compounds. Our results suggest that these enzymes interact functionally and form an integrated system that operates in a concerted manner to regulate tumor growth and consequently may be potential therapeutic targets for the control of proliferation as well as metastatic potential of cancer cells.
Synthesising Textures Using Variable Neighbourhood Searching

Texture synthesis aims to define and reproduce discriminat- ing image features. These features are used to associate with and dif- ferentiate between two textures. Often texture is composed of a pattern with an element of randomness in each feature's appearance, position and orientation. The goal is to imitate the sample texture in such a way that sample and synthesised texture are perceived to be generated by the same source. One of the recent texture synthesis methods selects an output pixel by searching with its already generated neighbourhood for a corresponding match in the sample image. The neighbourhood size is fixed and blurring of texture features often results. Our method attempts to avoid this problem by enabling a dynamic, accelerated neighbourhood search. The window size varies with each output pixel and is determined by the current neighbourhood intensity configuration.
Offshoring and Labor Markets

In this paper, we survey the recent empirical literature on the effects of offshoring on wage, employment, and displacement. We start with an overview of the measurement of offshoring, organizing our discussion around the three key elements of offshoring: that it involves intermediate inputs for production (versus final goods for consumption); that it involves imported inputs (versus domestically produced ones); and that the inputs involved could have been produced internally within the same firm. We then briefly discuss the theories of offshoring and survey the literature that examines the wage effects of offshoring: the wave of studies using industry-level data; the wave using firm-level data; the wave using worker-level data; and the wave using matched worker-firm data. For each wave, we highlight the identification strategies used, critically assess its strengths and weaknesses, discuss its connections with theory, and draw out potential policy implications of its findings. Finally, we survey the literature that examines how offshoring affects employment and displacement. We highlight the recent development of a novel cohort-based approach that is specifically designed to address selection with displacement, and capable of identifying the overall effects of offshoring, including wage, displacement, and all other types of transitions. (JEL F23, J24, J31, J63, L24, M55)
Strategic and Operational Benefits of IOS-Enabled Interorganizational Integration

In this study, we employ the lens of the resource-based view of the firm to examine the strategic value of IOS-enabled interorganizational integration. We first develop the key construct of IOS-enabled interorganizational integration, identifying and defining its two dimensions: interorganizational system integration and business integration. Next, we propose that while the two dimensions have positive impacts on operational performance, only interorganizational business integration has strategic value. The data for this study were collected through a survey of firms in mainland China. The results provide empirical support for our propositions. The study contributes to research by providing a clear conceptualization of IOS-enabled interorganizational integration, establishing the theoretical link between its two dimensions and operational and strategic performance, developing scales for interorganizational system integration and business integration, as well as providing data on the IOS experience of Chinese firms.