Miracle-dz/UniFAR-FTUs huggingface dataset:
Time variability of active galactic nuclei and heating of cooling flows

There is increasing evidence that active galactic nucleus (AGN) feedback is important in the energetics of cooling flows in galaxies and galaxy clusters. It is possible that, in most cooling-flow clusters, radiative losses from the thermal plasma are balanced, over the cluster lifetime, by mechanical heating from the central radio source. We investigate the implications of the variability of AGN mechanical luminosity L m on observations of cooling flows and radio galaxies in general. It is natural to assume that l = In (L m /L X ) is a Gaussian process. Then L m will be lognormally distributed at fixed cooling luminosity L X , and the variance in a measure of L m will increase with the time resolution of the measure. We test the consistency of these predictions with existing data for cooling flows and radio galaxies. These tests hinge on the power spectrum P(ω) of the Gaussian process l(t). General considerations suggest that P is a power law P ∼ ω -β . Long-term monitoring of Seyfert galaxies combined with estimates of the duty cycle of quasars imply that β ≃ 1, which corresponds to flicker noise. The power spectra ofmicroquasars have similar values of β. We combine a sample of sources in cooling flows that have cavities with the assumption that the average mechanical luminosity of the AGN equals the cooling flow's X-ray luminosity. Given that the mechanical luminosities are characterized by flicker noise, we find that their spectral amplitudes ωP(ω) lie between the estimated amplitudes of quasars and the measured values for the radio luminosities of microquasars. The model, together with the observation that powerful radio galaxies lie within a narrow range in optical luminosity, predicts the luminosity function of radio galaxies. Both the shape and the normalization of the predicted function are in agreement with observations. Forthcoming radio surveys will test the prediction that the luminosity function turns over at about the smallest luminosities so far probed.
A Bayesian idealization of entity resolution

Network theory has progressed a long way since the Erdös-Rényi model, identifying many important real-world phenomena that a good random graph model should capture, and producing more realistic models to capture many of them. However, these models are largely limited to the domain of simple networks - nodes and links only - leaving remaining complications outside the realm of theory. In such cases, a practitioner with complicated data is left to make decisions or apply algorithms to compensate for these issues without the benefit of an underlying model. In this paper, we develop a simple generative model of the entity resolution problem. Noting its similarity to the association problem in data fusion, we develop principled inference equations for entity resolution analogous to those developed for data association. The framework for this effort is a ground-truth model for object states and for the network which links them, together with a Dirichlet process model for how the observed aliases of the objects are distributed among the observed transactions between them. The paper focuses on the derivation of the inference equations, and the result is demonstrated on an illustrative example. Because the framework is based on rigorous probabilistic models, it is particularly well suited to ambiguous scenarios in which no single entity resolution hypothesis is stands out as the correct one.
Nonstationary Optimization Approach for Finding Universal Portfolios

The definition of universal portfolio was introduced in the nancial literature in order to describe the class of portfolios which are constructed directly from the available observations of the stocks behavior without any assumptions about their statistical properties. Cover has shown that one can construct such portfolio using only observations of the past stock prices which generates the same asymptotic wealth growth as the best constant rebalanced portfolio which is constructed with the full knowledge of the future stock market behavior. In this paper we construct universal portfolios using totally different set of ideas drawn from nonstationary stochastic optimization. Also our portfolios yield the same asymptotic growth of wealth as the best constant rebalanced portfolio constructed with the perfect knowledge of the future, but they are less demanding computationally. Besides theoretical study, we present computational evidence using data from New York Stock Exchange which shows, among other things, superior performance of portfolios which explicitly take into account possible nonstationary market behavior.
Enzyme Activities and Substrate Degradation by Fungal Isolates on Cassava Waste During Solid State Fermentation

The growth and bioeonversion potential of selected strains growing on cassava waste substrate during solid state fermentation were assessed. Rhizopus stolonifer showed the highest and the fastest utilization of starch and cellulose in the cassava waste substrate. It showed 70% starch utilization and 81% cellulose utilization within eight days. The release of reducing sugars indicating the substrate saccharification or degradation potential of the organisms reached the highest value of 406.5 mg/g by R. stolonifer on cassava waste during the eighth day of fermentation. The protein content was gradually increased (89.4 mg/g) on the eighth day of fermentation in cassava waste by R. stolonifer. The eellulase and amylase activity is higher in R. stolonifer than A. niger and R chrysosporium. The molecular mass of purified amylase and eellulase seemed to be 75 KDal, 85 KDal respectively.
DFT-Based Closed-Form Covariance Matrix and Direct Waveforms Design for MIMO Radar to Achieve Desired Beampatterns

In multiple-input multiple-output (MIMO) radar, for desired transmit beampatterns, appropriate correlated waveforms are designed. To design such waveforms, conventional MIMO radar methods use two steps. In the first step, the waveforms covariance matrix ${\mathbf R}$ is synthesized to achieve the desired beampattern. Whereas in the second step, to realize the synthesized covariance matrix, actual waveforms are designed. Most of the existing methods use iterative algorithms to solve these constrained optimization problems. The computational complexity of these algorithms is very high, which makes them difficult to use in practice. In this paper, to achieve the desired beampattern, a low complexity discrete-Fourier-transform based closed-form covariance matrix design technique is introduced for an MIMO radar. The designed covariance matrix is then exploited to derive a novel closed-form algorithm to directly design the finite-alphabet constant-envelope waveforms for the desired beampattern. The proposed technique can be used to design waveforms for large antenna array to change the beampattern in real time. It is also shown that the number of transmitted symbols from each antenna depends on the beampattern and is less than the total number of transmit antenna elements.
Development of a Novel Thyroid Function Fluctuated Animal Model for Thyroid-Associated Ophthalmopathy

Background The establishment of a suitable and stable animal model is critical for research on thyroid-associated ophthalmopathy (TAO). In clinical practice, we found that patients treated with I-131 often exhibit TAO; therefore, we aimed to establish a novel thyroid function fluctuated animal model of TAO by simulating the clinical treatment process. Methods We treated SD rats with I-131 to damage the thyroid and then used sodium levothyroxine (L-T4) to supplement the thyroid hormone (TH) levels every seven days, leading to a fluctuating level of thyroid hormones that simulated the status of clinical TAO patients. Rats administered normal saline were considered as a control. The weight, intraocular pressure, and serum T3, T4, TSH and TRAb levels of the rats were measured, and the pathological changes were analyzed by H&E staining and transmission electron microscopy (TEM). Results The experimental rats (TAO group) exhibited significantly reduced weight and elevated intraocular pressure compared with the control rats. Meanwhile, the serum levels of T3 and T4 were up-regulated in the TAO group, but the TSH level decreased during the 10-week study. Moreover, increased numbers of blood vessels and inflammatory cell infiltrations were observed in the orbital tissues of the TAO rats, while no abnormal changes occurred in the control rats. The orbital myofibrils in the TAO rats appeared fractured and dissolved, with twisted structures. Mitochondrial swelling and vacuoles within the endoplasmic reticulum, swelling nerve fibers, shedding nerve myelin, and macrophages were found in the TAO group. Conclusion Rats treated with I-131 and sodium levothyroxine exhibited characteristics similar to those of TAO patients in the clinic, providing an effective and simple method for the establishment of a stable animal model for research on the pathogenesis and treatment of TAO.
Single Image Super Resolution via Manifold Approximation

Image super-resolution remains an important research topic to overcome the limitations of physical acquisition systems, and to support the development of high resolution displays. Previous example-based super-resolution approaches mainly focus on analyzing the co-occurrence properties of low resolution and high-resolution patches. Recently, we proposed a novel single image super-resolution approach based on linear manifold approximation of the high-resolution image-patch space [1]. The image super-resolution problem is then formulated as an optimization problem of searching for the best matched high resolution patch in the manifold for a given low-resolution patch. We developed a novel technique based on the l1 norm sparse graph to learn a set of low dimensional affine spaces or tangent subspaces of the high-resolution patch manifold. The optimization problem is then solved based on the learned set of tangent subspaces. In this paper, we build on our recent work as follows. First, we consider and analyze each tangent subspace as one point in a Grassmann manifold, which helps to compute geodesic pairwise distances among these tangent subspaces. Second, we develop a min-max algorithm to select an optimal subset of tangent subspaces. This optimal subset reduces the computational cost while still preserving the quality of the reconstructed high-resolution image. Third, and to further achieve lower computational complexity, we perform hierarchical clustering on the optimal subset based on Grassmann manifold distances. Finally, we analytically prove the validity of the proposed Grassmann-distance based clustering. A comparison of the obtained results with other state-of-the-art methods clearly indicates the viability of the new proposed framework.
Direct Dynamics for Free Radical Kinetics in Solution: Solvent Effect on the Rate Constant for the Reaction of Methanol with Atomic Hydrogen

We calculate the rate constant for the reaction •H + CH3OH → H2 + •CH2OH both in the gas phase and in aqueous solution at 298 K. To accomplish this, we apply two different methods to estimate the electronic energies along the reaction path. First, we use specific reaction parameters (SRP) to mix the exchange and correlation energies in Becke's adiabatic connection theory (AC-SRP) to optimize the model for the specific bond-breaking, bond-making combination under consideration. Second, we obtain the potential energy using a linear combination of the Hartree−Fock method and AM1 with specific reaction parameters (HF||AM1-SRP); in this linear mixing method, eight NDDO parameters and the linear mixing parameter are simultaneously optimized by a genetic algorithm. To calculate the reaction rate constants in solution, the solute atomic charges are represented by class IV charges, the electric polarization of the solvent is determined from the electronic charge distribution of the solute self-consistently, and th.
The use of ultrasound to facilitate the delivery of genetic-based therapeutic strategies

Gene therapy is the introduction of exogenous genes to a cell to "fool" the cell into producing the coding protein. There are ongoing studies in cancer-killing gene therapies, kidney cell regeneration and many genetic disorders such as cystic fibrosis and severe combined immunodeficiency (SCID). However, it has been discovered that developing the therapy is not enough. A method to deliver the drugs is equally important. The objective of this work was to explore two potential uses of ultrasound for gene delivery. The first is to determine if ultrasound-induced cavitation can be used to enhance in vivo transfection of gene therapy. Second, to use non-invasive ultrasonic heating to spatially control gene therapy expression in vivo after delivery. In the first phase of this project, feasibility experiments were performed to show an increase in transfection efficiency occurred when using microbubbles, ultrasound, plasmid and genes compared to plasmid and genes alone. An ultrasound transducer was then designed to optimize experimental conditions for invasive in vivo experiments taking into consideration optimal transducer size, focal distance, and frequency. When testing the transducer, a potential side effect to using ultrasound to increase transfection was discovered. In the second phase of exploration, the use of MRI-monitored ultrasound to induce enhanced expression of luciferase after local injection of the gene construct Ad-HSP-Luc was explored. Using a construct that includes an hsp promoter allows the activation of the associated transgene only in areas that are subsequently heated after injection. Increased luciferase expression was observed in areas that were exposed to ultrasonic heating. It is hoped that the positive results of these preliminary experiments will eventually lead to a clinical methodology where ultrasound-enhanced gene therapy transfection would be followed with ultrasound-directed spatial control of gene expression. Thesis Supervisor: Kullervo Hynynen Title: Professor of Radiology, Harvard Medical School
Reconstructing the History of Mesoamerican Populations through the Study of the Mitochondrial DNA Control Region

The study of genetic information can reveal a reconstruction of human population’s history. We sequenced the entire mtDNA control region (positions 16.024 to 576 following Cambridge Reference Sequence, CRS) of 605 individuals from seven Mesoamerican indigenous groups and one Aridoamerican from the Greater Southwest previously defined, all of them in present Mexico. Samples were collected directly from the indigenous populations, the application of an individual survey made it possible to remove related or with other origins samples. Diversity indices and demographic estimates were calculated. Also AMOVAs were calculated according to different criteria. An MDS plot, based on FST distances, was also built. We carried out the construction of individual networks for the four Amerindian haplogroups detected. Finally, barrier software was applied to detect genetic boundaries among populations. The results suggest: a common origin of the indigenous groups; a small degree of European admixture; and inter-ethnic gene flow. The process of Mesoamerica’s human settlement took place quickly influenced by the region’s orography, which development of genetic and cultural differences facilitated. We find the existence of genetic structure is related to the region’s geography, rather than to cultural parameters, such as language. The human population gradually became fragmented, though they remained relatively isolated, and differentiated due to small population sizes and different survival strategies. Genetic differences were detected between Aridoamerica and Mesoamerica, which can be subdivided into “East”, “Center”, “West” and “Southeast”. The fragmentation process occurred mainly during the Mesoamerican Pre-Classic period, with the Otomí being one of the oldest groups. With an increased number of populations studied adding previously published data, there is no change in the conclusions, although significant genetic heterogeneity can be detected in Pima and Huichol groups. This result may be explained because populations historically assigned as belonging to the same group were, in fact, different indigenous populations.
Exchange Rates, Expected Returns and Risk: UIP Unbound

No-arbitrage implies a close link between exchange rates and interest returns, but evidence of that link has been elusive. This paper derives an exchange rate asset price model with consumption-risk adjustments. Interest rates and exchange rates reflect common risks which bias their reduced-form relationship. As markets become more complete, the model predicts increasing disconnect between exchange rates and observed interest rates, and between premia that price bonds and premia that price currency returns. When accounting for risk, the estimated interest rate - exchange rate relationship is considerably closer to theory for eight USD currency pairs. Exchange rates, risk and returns need to be jointly modeled.
Studentische Bewertung und Präferenz von Hochschulprüfungen mit Aufgaben im offenen und geschlossenen Antwortformat

Zusammenfassung. Multiple-Choice-Aufgaben (MCA) werden gegenüber Freitextaufgaben (Constructed-Response-Aufgaben [CRA]) in Hochschulprüfungen zunehmend eingesetzt. Diese Studie betrachtet formatspezifische Einstellungen und Präferenzen von Studierenden, die relevant für selbstreguliertes Lernverhalten sein könnten (vgl. Assessment Drives Learning). Dreihundertfünfzig Studierende bewerteten MCA und CRA auf verschiedenen Dimensionen separat, aber mit identischen Frageformulierungen. Wie angenommen finden sich signifikante ( p ≤ .001) Bewertungsunterschiede: Die Erwartung eines (geringeren) Lernaufwandes ( d = 1.22), die Erfolgserwartung von Testbearbeitungsstrategien ( d = 0.70) sowie die wahrgenommene Bewertungsobjektivität ( d = 1.47) und Fairness ( d = 0.27) fielen höher für MCA gegenüber CRA aus. CRA schnitten dagegen hinsichtlich des wahrgenommenen Potenzials Leistung zu zeigen deutlich stärker ab ( d = –2.53). Allgemein zeigten sich eher individuelle Präferenzen zugunsten eines der Formate, die teilweise durch die Formatbewertungen erklärbar waren. Implikationen für die Prüfungspraxis an Hochschulen werden diskutiert.
Non-Gaussian Velocity Distribution Function in a Vibrating Granular Bed

The simulation of granular particles in a quasi-two-dimensional container under vertical vibration as an experimental accessible model for granular gases is performed. The velocity distribution function obeys an exponential-like function during the vibration and deviates from the exponential function in free-cooling states. It is confirmed that this exponential-like distribution function is produced by Coulomb friction force. A Langevin equation with Coulomb friction is proposed to describe the motion of such a system.
The hierarchical formation of the brightest cluster galaxies

We use semi-analytic techniques to study the formation and evolution of brightest cluster galaxies (BCGs). We show the extreme hierarchical nature of these objects and discuss the limitations of simple ways to capture their evolution. In a model where cooling flows are suppressed at late times by active galactic nucleus (AGN) activity, the stars of BCGs are formed very early (50 per cent at z ∼ 5, 80 per cent at z ∼ 3) and in many small galaxies. The high star formation rates in these high-z progenitors are fuelled by rapid cooling, not by merger-triggered starbursts. We find that model BCGs assemble surprisingly late: half their final mass is typically locked up in a single galaxy after z ∼ 0.5. Because most of the galaxies accreted on to BCGs have little gas content and red colours, late mergers do not change the apparent age of BCGs. It is this accumulation of a large number of old stellar populations - driven mainly by the merging history of the dark matter halo itself - that yields the observed homogeneity of BCG properties. In the second part of the paper, we discuss the evolution of BCGs to high redshifts, from both observational and theoretical viewpoints. We show that our model BCGs are in qualitative agreement with high-z observations. We discuss the hierarchical link between high-z BCGs and their local counterparts. We show that high-z BCGs belong to the same population as the massive end of local BCG progenitors, although they are not in general the same galaxies. Similarly, high-z BCGs end up as massive galaxies in the local Universe, although only a fraction of them are actually BCGs of massive clusters.
Examining plasma microRNA markers for colorectal cancer at different stages

Circulating microRNAs (miRNAs) have emerged as promising biomarkers; however, few miRNAs have been reproducible and can be used in clinical practice. In this study, we screened the levels of 754 miRNAs using TaqMan array in 50 individual plasma samples from 10 demographically matched healthy controls and 40 colorectal cancer (CRC) patients (10 each of stage I–IV) and identified 22 miRNAs associated with the presence of and stages of CRC. Then we performed the validation for 11 miRNAs in an independent cohort including 187 CRC cases and 47 healthy controls. Comprehensive analyses showed that plasma miR-96 distinguished stage I–IV CRC from healthy controls with an area under curve (AUC) of 0.740; miR-203 separated stage III–IV CRC patients from stage I–II with an AUC of 0.757; and miR-141 differentiated stage IV CRC from stage I–III patients with an AUC of 0.851. Survival analyses showed that plasma miR-96 and miR-200b were independent prognostic factors for overall survival. Thus, we propose four miRNAs (miR-96, miR-203, miR-141 and miR-200b) as clinically validated circulating biomarkers for CRC prognosis that warrant further evaluation for clinical utility.
Blocking analysis of dynamic lightpath establishment in wavelength-routed networks

In this paper, we analyze the blocking probability of dynamic lightpath establishment in wavelength-routed networks. By using the destination-initiated reservation (DIR) method as a case study, we analyze traffic blocking occurring due to insufficient network capacity as well as traffic blocking caused by outdated information. Simulation results show the proposed models to be highly accurate.
Internal versus External cluster validation indexes

One of fundamental challenges of clustering is how to evaluate results, without auxiliary information. A common approach for evaluation of clustering results is to use validity indexes. Clustering validity approaches can use three criteria: External criteria (evaluate the result with respect to a pre-specified structure), internal criteria (evaluate the result with respect a information intrinsic to the data alone). Consequently, different types of indexes are used to solve different types of problems and indexes selection depends on the kind of available information. That is why in this paper we show a comparison between external and internal indexes. Results obtained in this study indicate that internal indexes are more accurate in group determining in a given clustering structure. Six internal indexes were used in this study: BIC, CH, DB, SIL, NIVA and DUNN and four external indexes (F-measure, NMIMeasure, Entropy, Purity). The clusters that were used were obtained through clustering algorithms K-means and Bissecting-K- means.