Miracle-dz/UniFAR-FTUs huggingface dataset:
Mixing Times for Random Walks on Geometric Random Graphs

A geometric random graph, Gd(n, r), is formed as follows: place n nodes uniformly at random onto the surface of the d-dimensional unit torus and connect nodes which are within a distance r of each other. The Gd(n, r) has been of great interest due to its success as a model for ad-hoc wireless networks. It is well known that the connectivity of Gd(n, r) exhibits a threshold property: there exists a constant αd such that for any " > 0, for rd αd(1 + ") log n/n the Gd(n, r) is connected w.h. p. In this paper, we study mixing properties of random walks on Gd(n, r) for rd(n) = ω(log n/n). Specifically, we study the scaling of mixing times of the fastest-mixing reversible random walk, and the natural random walk. We find that the mixing time of both of these random walks have the same scaling laws and scale proportional to r−2 (for all d). These results hold for Gd(n, r) when distance is defined using any Lp norm. Though the results of this paper are not so surprising, they are nontrivial and require new methods. To obtain the scaling law for the fastest-mixing reversible random walk, we first explicitly characterize the fastest-mixing reversible random walk on a regular (grid-type) graph in d dimensions. We subsequently use this to bound the mixing time of the fastest-mixing random walk on Gd(n, r). In the course of our analysis, we obtain a tight relation between the mixing time of the fastest-mixing symmetric random walk and the fastest-mixing reversible random walk with a specified equilibrium distribution on an arbitrary graph. ∗Author names appear in alphabetical order. †This work is supported in part by a Stanford Graduate Fellowship, and by C2S2, the MARCO Focus Center for Circuit and System Solution, under MARCO contract 2003-CT-888. 1In this paper, with high probability (w.h.p.) means with probability at least 1 − 1/n2. To study the natural random walk, we first generalize a method of [DS91] to bound eigenvalues based on Poincare’s inequality and then apply it to the Gd(n, r) graph. We note that the methods utilized in this paper are novel and general enough to be useful in the context of other graphs.
Contest Design When Winners Gain Advantage ∗

We consider a principal who can distribute a prize fund over two consecutive contests. The winner of contest one gains an advantage in contest two; this win advantage affects his cost of exerting effort in the second contest and his effort productivity in the second contest. We find that, without discounting among contestants, the two aspects of the win advantage work the same, with the principal choosing to have the full prize fund in the second contest. This result is modified when contestants discount future payoffs.
Gene expression profiling of CD 8 + T cells predicts prognosis in patients with Crohn disease and ulcerative colitis

Crohn disease (CD) and ulcerative colitis (UC) are increasingly common, chronic forms of inflammatory bowel disease. The behavior of these diseases varies unpredictably among patients. Identification of reliable prognostic biomarkers would enable treatment to be personalized so that patients destined to experience aggressive disease could receive appropriately potent therapies from diagnosis, while those who will experience more indolent disease are not exposed to the risks and side effects of unnecessary immunosuppression. Using transcriptional profiling of circulating T cells isolated from patients with CD and UC, we identified analogous CD8+ T cell transcriptional signatures that divided patients into 2 otherwise indistinguishable subgroups. In both UC and CD, patients in these subgroups subsequently experienced very different disease courses. A substantially higher incidence of frequently relapsing disease was experienced by those patients in the subgroup defined by elevated expression of genes involved in antigendependent T cell responses, including signaling initiated by both IL-7 and TCR ligation — pathways previously associated with prognosis in unrelated autoimmune diseases. No equivalent correlation was observed with CD4+ T cell gene expression. This suggests that the course of otherwise distinct autoimmune and inflammatory conditions may be influenced by common pathways and identifies what we believe to be the first biomarker that can predict prognosis in both UC and CD from diagnosis, a major step toward personalized therapy. Research Article
Contextual conditions on stem alternations Illustrations from the Spanish conjugation

This paper looks at the analysis of stem alternations: a type of non-affixal morphological change. Alternations of this type are controversial because they look in principle like they can be analyzed either with distinct stem forms in memory, or with (morpho)phonological rules that derive alternants from a single underlying form. I argue that the locality conditions on contextual allomorphy provide an answer to part of this controversy. It is shown that certain stem alternations in Spanish verbs–diphthongization, as in e.g. pensar/pienso (‘think’); raising, as in e.g. pedir/pido (‘ask’) – cannot be treated with stored stems, because the alternations do not occur under the locality conditions that apply to contextual allomorphy. These alternations must be treated (morpho) phonologically. The implications of this view are explored; this includes a conjecture that reclassifies different types of “morpheme specific” alternations in the grammar.
Testing of collagenase covalently linked to chitosan nanofibers for biomedical applications

Nanofibers biofunctionalized with enzymes are materials of interest in the biomedical field due to their potential application in wound healing. This work describes the production and characterisation of electrospun chitosan nanofibers biofunctionalized with a microbial collagenase. The morphology and microstructure of the chitosan nanofibers prepared with Nanospider technology were examined using a scanning electron microscope (SEM). Amino groups of a chitosan nanofiber were connected with the carboxylic acid groups of the collagenase using EDAC and sulfo-NHS methodology. Collagenase enzymatic activity was evaluated with a peptidic substrate (Pz-peptide, 4-phenylazobenzyloxycarbonyl-Pro-Leu-GlyPro-D-Arg) in order to estimate the ability of this biomaterial to be used as an enzymatic debriding wound dressing. The characterisation of collagenase chitosan nanofibers in terms of measuring apparent MichaelisMenten constants (KM(app) and vmax) revealed a higher enzyme to substrate affinity than with the soluble form of the collagenase. The resulting novel collagenase chitosan nanofibers exhibited excellent operational stability and long shelf life for at least 6 weeks. Therefore, the novel collagenase chitosan nanofibers are expected to be a potential scaffold for wound healing applications, such as e.g. enzymatic debridement.
Divergent Sapovirus Strains and Infection Prevalence in Wild Carnivores in the Serengeti Ecosystem: A Long-Term Study

The genus Sapovirus, in the family Caliciviridae, includes enteric viruses of humans and domestic animals. Information on sapovirus infection of wildlife is limited and is currently lacking for any free-ranging wildlife species in Africa. By screening a large number of predominantly fecal samples (n = 631) obtained from five carnivore species in the Serengeti ecosystem, East Africa, sapovirus RNA was detected in the spotted hyena (Crocuta crocuta, family Hyaenidae), African lion (Panthera leo, family Felidae), and bat-eared fox (Otocyon megalotis, family Canidae), but not in golden or silver-backed jackals (Canis aureus and C. mesomelas, respectively, family Canidae). A phylogenetic analysis based on partial RNA-dependent RNA polymerase (RdRp) gene sequences placed the sapovirus strains from African carnivores in a monophyletic group. Within this monophyletic group, sapovirus strains from spotted hyenas formed one independent sub-group, and those from bat-eared fox and African lion a second sub-group. The percentage nucleotide similarity between sapoviruses from African carnivores and those from other species was low (< 70.4%). Long-term monitoring of sapovirus in a population of individually known spotted hyenas from 2001 to 2012 revealed: i) a relatively high overall infection prevalence (34.8%); ii) the circulation of several genetically diverse variants; iii) large fluctuations in infection prevalence across years, indicative of outbreaks; iv) no significant difference in the likelihood of infection between animals in different age categories. The likelihood of sapovirus infection decreased with increasing hyena group size, suggesting an encounter reduction effect, but was independent of socially mediated ano-genital contact, or the extent of the area over which an individual roamed.
S Y ] 2 M ay 2 01 8 On the primal-dual dynamics of Support Vector Machines

The aim of this paper is to study the convergence of the primal-dual dynamics pertaining to Support Vector Machines (SVM). The optimization routine, used for determining an SVM for classification, is first formulated as a dynamical system. The dynamical system is constructed such that its equilibrium point is the solution to the SVM optimization problem. It is then shown, using passivity theory, that the dynamical system is global asymptotically stable. In other words, the dynamical system converges onto the optimal solution asymptotically, irrespective of the initial condition. Simulations and computations are provided for corroboration.
Projected BNNs : Avoiding weight-space pathologies by projecting neural network weights

While modern neural networks are making remarkable gains in terms of predictive accuracy, characterizing uncertainty over the parameters of these models (in a Bayesian setting) is challenging because of the high-dimensionality of the network parameter space and the correlations between these parameters. We introduce a novel inference framework that encodes complex distributions in high-dimensional parameter space with representations in a low-dimensional latent space. We show improvements in uncertainty characterization and generalization across a large array of synthetic and real-world datasets.
Decomposition of Changes in Earnings Inequality in China: A Distributional Approach

Using the nationwide household data, this study examines the changes in the Chinese urban income distributions from 1987 to 1996 and from 1996 to 2004, and investigates the causes of these changes. The Oaxaca-Blinder decomposition method is applied to decomposing the mean earnings increases, and the Firpo-Fortin-Lemieux method based upon a recentered influence function is used to decompose the changes in the income distribution and the inequality measures such as the variance and the 10-90 ratio. The decomposition results show that the wage structure effects such as the widened gender pay gap, the increasing return to college education, and the widened gap in the return to different industries, ownership, and regions, have contributed to most of the overall increases in income inequality. During the different time periods, 1987-1996 and 1996-2004, the impacts of these factors vary at the different points (e.g. the lower half or upper half) of distribution.
Human Activity Recognition Using Shape and Motion Features

Action representation for robust human activity recognition is still a challenging problem in human-robot interaction. In this paper, we present two new methods for action recognition. The first method, named SIFT Motion Estimation (SIFT-ME), is derived from SIFT correspondences in a sequence of video frames and adds tracking information to describe articulated human body motion. SIFT-ME contains 2D transformation parameters of image features for describing planar motions including translation and rotation. The second method, named 2D Distal-Limb Human Activity Recognition Using Shape and Motion Features ــــــــــــــ ـ ـــــــــــــ ــــــــــــ University Bulletin – ISSUE No. 20Vol. (1) – March2018. 126 Skeletonization, accurately extracts the distal segments of human limbs by fitting a nine-element stick figure to the human silhouette. This skeleton model provides precise endpoints of the distal segments of each limb which are reduced to centroids for efficient recognition. As we believe the distal limb segments (e.g. forearms and shins) provide sufficient and compact information for human activity recognition, we compress the nine-segment skeleton to these four segments. Each limb centroid is described by its angle with respect to the vertical body axis to create an action descriptor vector with six elements which represent the position of the torso and four limb segments. The six-element descriptor is detected and tracked without any manual initialization. It is also invariant to image resolution, illumination and video frame rates, making it suitable for a wide range of human tracking applications from real time surveillance to human-robot interaction. For both methods, a Gaussian Mixture Model is used to represent action descriptors for several human activities. Then, the maximum log-likelihood criterion is utilized for clossification.
THE BARYON CYCLE OF DWARF GALAXIES: DARK, BURSTY, GAS-RICH POLLUTERS

We present results from a fully cosmological, very high-resolution, ΛCDM simulation of a group of seven field dwarf galaxies with present-day virial masses in the range Mvir = 4.4 × 108–3.6 × 1010 M☉. The simulation includes a blastwave scheme for supernova feedback, a star-formation recipe based on a high gas density threshold, metal-dependent radiative cooling, a scheme for the turbulent diffusion of metals and thermal energy, and a uniform UV background. The properties of the simulated dwarfs are strongly modulated by the depth of the gravitational potential well. All three halos with Mvir < 109 M☉ are devoid of stars, as they never reach the density threshold for star formation of 100 atoms cm−3. The other four, Mvir > 109 M☉ dwarfs have blue colors, low star-formation efficiencies, high cold gas-to-stellar mass ratios, and low stellar metallicities. Their bursty star-formation histories are characterized by peak specific star-formation rates in excess of 50–100 Gyr−1, far outside the realm of normal, more massive galaxies. The median stellar age of the simulated galaxies decreases with decreasing halo mass, with the two Mvir ≃ 2–3 × 109 M☉ dwarfs being predominantly young, and the two more massive systems hosting intermediate and older populations. The cosmologically young dwarfs are lit up by tidal interactions, have compact morphologies, and have metallicities and cold gas fractions similar to the relatively quiescent, extremely metal-deficient dwarf population. Metal-enriched galactic outflows produce sub-solar effective yields and pollute with heavy elements a megaparsec-size region of the intergalactic medium, but are not sufficient to completely quench star-formation activity and are absent in the faintest dwarfs.
A cross-layer design for improving TCP performance in opportunistic networks

Opportunistic networks have attracted attention from researchers because of their inherent characteristics, including long latency, low data rate, and intermittent connectivity. Extensive research has been conducted on opportunistic networks, including the architecture and routing. However, few researchers have investigated the performance of TCP in opportunistic networks, especially when Epidemic Routing is used. In this paper, we first evaluate the performance of TCP in opportunistic networks with Epidemic Routing. Our results show that the Epidemic Routing in opportunistic networks degrades the performance of TCP due to too many multicopy data packets and in turn consume limited resource. Then a cross-layer design based on TCP and Epidemic Routing, named ACK-EPI is proposed to solve the above problem. ACK-EPI can avoid the packets that have already been delivered being forwarded again in the network. The simulation results show that ACK-EPI outperforms the Epidemic Routing in opportunistic networks.
Melatonin Prevents Pigment Gallstone Formation Induced by Bile Duct Ligation in Guinea Pigs

Free radical‐mediated oxidative stress has been implicated in the genesis of gallstone in vitro. This study was designed to examine the oxidative stress changes during pigment gallstone formation and to investigate whether melatonin (MLT) could act as a chemopreventive agent for cholelithiasis in a guinea pig model. The common bile duct of guinea pigs was ligated with or without MLT pretreatment. Animals were studied on day 7, 9, 12, and 14 after surgery. Stone and/or sludge developed in ligated guinea pigs without MLT. Fourier transform infrared spectra of the sludge showed the presence of calcium bilirubinate, whose peak height per milligram of sludge gradually increased with time after ligation. Total antioxidant activity (TAA) in bile of guinea pigs at day 14 after ligation reduced to one third of the level in sham‐operated controls (P < .001). In addition, the bile of ligated guinea pigs had increased pH (P < .001), bile salts (P < .01), and malondialdehyde (MDA) (P < .05), compared to sham controls. Pretreatment of guinea pigs with MLT at a dose of 1,000 μg/kg significantly decreased the incidence of pigment gallstone formation at day 14 after ligation, as compared to no pretreatment (0/7 vs. 8/10). MLT also reverted the ligation‐induced changes in biliary bile salts, pH, MDA, and TAA to control levels. These in vivo findings support a causative role of oxidative stress in the bile duct ligation–induced pigment gallstone formation. Antioxidants may prove useful in preventing pigment gallstone formation in humans.
Recent Advances in Extraction and Stirring Integrated Techniques

The extraction yield of a microextraction technique depends on thermodynamic and kinetics factors. Both of these factors have been the focus of intensive research in the last few years. The extraction yield can be increased by synthesizing and using novel materials with favorable distribution constants (one of the thermodynamic factors) for target analytes. The extraction yield can also be increased by improving kinetic factors, for example, by developing new extraction modes. Microextraction techniques are usually non-exhaustive processes that work under the kinetic range. In such conditions, the improvement of the extraction kinetics necessarily improves the performance. Since the extraction yield and efficiency is related to how fast the analytes diffuse in samples, it is crucial to stir the sample during extraction. The stirring can be done with an external element or can be integrated with the extraction element in the same device. This article reviews the main recent advances in the so-called extraction/stirring integrated techniques with emphasis on their potential and promising approaches rather than in their applications.
Conditions Under Which Genome-Wide Association Studies Will be Positively Misleading

Genome-wide association mapping is a popular method for using natural variation within a species to generate a genotype–phenotype map. Statistical association between an allele at a locus and the trait in question is used as evidence that variation at the locus is responsible for variation of the trait. Indirect association, however, can give rise to statistically significant results at loci unrelated to the trait. We use a haploid, three-locus, binary genetic model to describe the conditions under which these indirect associations become stronger than any of the causative associations in the organism—even to the point of representing the only associations present in the data. These indirect associations are the result of disequilibrium between multiple factors affecting a single trait. Epistasis and population structure can exacerbate the problem but are not required to create it. From a statistical point of view, indirect associations are true associations rather than the result of stochastic noise: they will not be ameliorated by increasing sampling size or marker density and can be reproduced in independent studies.
Legal Traditions and Initial Endowments in Shaping the Path of Financial Development

This paper finds remarkable heterogeneity in the relationship between legal traditions and finance in former colonies. The effect of the British common law on financial development is conditioned by the level of initial endowments. In former colonies with low precolonial population density, the common law has promoted high financial development, but where endowments were abundant, this legal tradition has not worked well. In contrast, the effect of the French civil law on finance is invariant to endowments. British common law countries do not exhibit greater financial development levels than French civil law countries when endowments are sufficiently high.
Sketch-based interface for interaction with unmanned air vehicles

In order to decrease the number of casualties and limit the number of potentially dangerous situations that Soldiers encounter, the US military is exploring the use of autonomous Unmanned Aircraft Systems (UAS) to fulfill air support requests (ASR) from the field. The interface for this system must provide interaction in modes that facilitate the completion of the support request in various scenarios, and it must be usable by operators of all skill levels, without requiring extensive training or considerable expertise. Sketches are a simple and natural way to exchange information and ideas. Sketching as a form of human-computer interaction can be very useful in areas where information is represented graphically. In this paper we present the development of an interface that that allows the user to plan an ASR using sketch and other inputs while conforming to the user's mental model of natural interaction.
Design of PDMS membrane for CTC separation

Circulating tumorcells(CTC) are the primary tumor cells which contains the key information about the cancer. These CTCs can be separated from the peripheral blood in microfluidics, where a PDMS(polydimethylsiloxane) membrane can be designed for CTC detection. The PDMS membrane is designed with cylindrical pores for the detection of Circulating TumorCells(CTC) from the peripheral blood samples. The membrane consisting of cylindrical pores of size 9μm and the distance between the pores are designed to be (15μm) are simulated and analysed for the separation of CTCs.
A Less Effective Monetary Transmission in the Wake of Emu? Evidence from Lending Rates Pass-Through

A new approach to search for structural breaks in the retail lending rates pass-through in the wake of EMU is proposed and implemented for Italy and Portugal. The econometric exercise shows that breakpoints cluster in the second semester 1999 and that the pass-through on short term lending is, in contrast with earlier research, sizeably lower in the post-break period. The recently proposed distinction between monetary policy and cost-of-funds approaches in the pass-through analysis does not yield different breakpoints. These results challenge the widely held view that EMU has in its wake enhanced the effectiveness of monetary transmission via the banking sector and made it more uniform across countries, because of rising and converging pass-throughs. A strengthened relationship lending could at least partly explain the reduced pass-through in the Italian case.