Miracle-dz/UniFAR-FTUs huggingface dataset:
SquirRL: Automating Attack Analysis on Blockchain Incentive Mechanisms with Deep Reinforcement Learning

—Incentive mechanisms are central to the functionality of permissionless blockchains: they incentivize participants to run and secure the underlying consensus protocol. Designing incentive-compatible incentive mechanisms is notoriously challenging, however. As a result, most public blockchains today use incentive mechanisms whose security properties are poorly understood and largely untested. In this work, we propose SquirRL, a framework for using deep reinforcement learning to analyze attacks on blockchain incentive mechanisms. We demonstrate SquirRL’s power by ﬁrst recovering known attacks: (1) the optimal selﬁsh mining attack in Bitcoin [56], and (2) the Nash equilibrium in block withholding attacks [18]. We also use SquirRL to obtain several novel empirical results. First, we discover a counterintuitive ﬂaw in the widely used rushing adversary model when applied to multi-agent Markov games with incomplete information. Second, we demonstrate that the optimal selﬁsh mining strategy identiﬁed in [56] is actually not a Nash equilibrium in the multi-agent selﬁsh mining setting. In fact, our results suggest (but do not prove) that when more than two competing agents engage in selﬁsh mining, there is no proﬁtable Nash equilibrium . This is consistent with the lack of observed selﬁsh mining in the wild. Third, we ﬁnd a novel attack on a simpliﬁed version of Ethereum’s ﬁnalization mechanism, Casper the Friendly Finality Gadget (FFG) that allows a strategic agent to amplify her rewards by up to 30% . Notably, [12] shows that honest voting is a Nash equilibrium in Casper FFG; our attack shows that when Casper FFG is composed with selﬁsh mining, this is no longer the case. Altogether, our experiments demonstrate SquirRL’s ﬂexibility and promise as a framework for studying attack settings that have thus far eluded theoretical and empirical understanding.
Apparent superluminal core expansion and limb brightening in the candidate neutrino blazar TXS 0506+056

Context.IceCube has reported a very-high-energy neutrino (IceCube-170922A) in a region containing the blazarTXS 0506+056. Correlated gamma-ray activity has led to the first high-probability association of a high-energy neutrino with an extragalactic source. This blazar has been found to be in a radio outburst during the neutrino event.Aims. Our goal is to probe the sub-milliarcsecond properties of the radio jet right after the neutrino detection and during the further evolution of the radio outburst.Methods. We performed target of opportunity observations at 43 GHz frequency using very long baseline interferometry imaging, corresponding to 7 mm in wavelength, with the Very Long Baseline Array two and eight months after the neutrino event.Results. We produced two images of the radio jet of TXS 0506+056 at 43 GHz with angular resolutions of (0.2 × 1.1) mas and (0.2 × 0.5) mas, respectively. The source shows a compact, high brightness temperature core, albeit not approaching the equipartition limit and a bright and originally very collimated inner jet. Beyond approximately 0.5 mas from the millimeter-VLBI core, the jet loses this tight collimation and expands rapidly. During the months after the neutrino event associated with this source, the overall flux density is rising. This flux density increase happens solely within the core. Notably, the core expands in size with apparent superluminal velocity during these six months so that the brightness temperature drops by a factor of three despite the strong flux density increase.Conclusions. The radio jet of TXS 0506+056 shows strong signs of deceleration and/or a spine-sheath structure within the inner 1 mas, corresponding to about 70–140 pc in deprojected distance, from the millimeter-VLBI core. This structure is consistent with theoretical models that attribute the neutrino and gamma-ray production in TXS 0506+056 to interactions of electrons and protons in the highly relativistic jet spine with external photons originating from a slower moving jet region. Proton loading due to jet-star interactions in the inner host galaxy is suggested as the possible cause of deceleration.
Template co-updating in multi-modal human activity recognition systems

Multi-modal systems are quite common in the context of human activity recognition since widely used RGB-D sensors give access to parallel data streams (RGB, depth, skeleton). This paper is aimed at defining a general framework for unsupervised template updating in multi-modal systems, where the different data sources can provide complementary information, increasing the effectiveness of the updating procedure and reducing at the same time the probability of incorrect template modifications.
Fast Color-guided Depth Denoising for RGB-D Images by Graph Filtering

Depth images captured by off-the-shelf RGB-D cameras suffer from much stronger noise than color images. In this paper, we propose a method to denoise the depth images in RGB-D images by color-guided graph filtering. Our iterative method contains two components: color-guided similarity graph construction, and graph filtering on the depth signal. Implemented in graph vertex domain, filtering is accelerated as computation only occurs among neighboring vertices. Experimental results show that our method outperforms state-of-art depth image denoising methods significantly both on quality and efficiency.
Bipolar planetary nebulae from outflow collimation by common envelope evolution

The morphology of bipolar planetary nebulae (PNe) can be attributed to interactions between a fast wind from the central engine and dense toroidal shaped ejecta left over from common envelope (CE) evolution. Here we use the 3-D hydrodynamic AMR code AstroBEAR to study the possibility that bipolar PN outflows can emerge collimated even from an uncollimated spherical wind in the aftermath of a CE event. The output of a single CE simulation via the SPH code PHANTOM serves as the initial conditions. Four cases of winds, all with high enough momenta to account for observed high momenta preplanetary nebula outflows, are injected spherically from the region of the CE binary remnant into the ejecta. We compare cases with two different momenta and cases with no radiative cooling versus application of optically thin emission via a cooling curve to the outflow. Our simulations show that in all cases highly collimated bipolar outflows result from deflection of the spherical wind via the interaction with the CE ejecta. Significant asymmetries between the top and bottom lobes are seen in all cases. The asymmetry is strongest for the lower momentum case with radiative cooling. While real post CE winds may be aspherical, our models show that collimation via "inertial confinement" will be strong enough to create jet-like outflows even beginning with maximally uncollimated drivers. Our simulations reveal detailed shock structures in the shock focused inertial confinement (SFIC) model and develop a lens-shaped inner shock that is a new feature of SFIC driven bipolar lobes.
A Study of Black Box Adversarial Attacks in Computer Vision

Machine learning has seen tremendous advances in the past few years which has lead to deep learning models being deployed in varied applications of day-to-day life. Attacks on such models using perturbations, particularly in real-life scenarios, pose a serious challenge to their applicability, pushing research into the direction which aims to enhance the robustness of these models. After the introduction of these perturbations by Szegedy et al., significant amount of research has focused on the reliability of such models, primarily in two aspects - white-box, where the adversary has access to the targeted model and related parameters; and the black-box, which resembles a real-life scenario with the adversary having almost no knowledge of the model to be attacked. We propose to attract attention on the latter scenario and thus, present a comprehensive comparative study among the different adversarial black-box attack approaches proposed till date. The second half of this literature survey focuses on the defense techniques. This is the first study, to the best of our knowledge, that specifically focuses on the black-box setting to motivate future work on the same.
Evidence of superfluidity in a dipolar supersolid from nonclassical rotational inertia

A supersolid rotation When a bucket of water is rotated, the water rotates with the vessel, contributing to the total moment of inertia. If such an experiment were done with a superfluid, it would decouple from the vessel and would not contribute to rotation. Tanzi et al. studied an intermediate case, a supersolid, which is predicted to only partially decouple, resulting in a moment of inertia smaller than the classical value. Whereas previous such experiments were done with helium, the authors used a gas of highly magnetic dysprosium atoms in an optical trapping potential that was suddenly changed, causing the gas to oscillate. Measuring the frequency of these oscillations provides evidence for a reduced moment of inertia. Science, this issue p. 1162 The scissors mode of an ultracold gas of dysprosium atoms in a supersolid state shows signatures of superfluidity. A key manifestation of superfluidity in liquids and gases is a reduction of the moment of inertia under slow rotations. Nonclassical rotational effects have also been considered in the context of the elusive supersolid phase of matter, in which superfluidity coexists with a lattice structure. Here, we show that the recently discovered supersolid phase in dipolar quantum gases features a reduced moment of inertia. Using a dipolar gas of dysprosium atoms, we studied a peculiar rotational oscillation mode in a harmonic potential, the scissors mode, previously investigated in ordinary superfluids. From the measured moment of inertia, we deduced a superfluid fraction that is different from zero and of order of unity, providing direct evidence of the superfluid nature of the dipolar supersolid.
AMR-to-Text Generation with Cache Transition Systems

Text generation from AMR involves emitting sentences that reflect the meaning of their AMR annotations. Neural sequence-to-sequence models have successfully been used to decode strings from flattened graphs (e.g., using depth-first or random traversal). Such models often rely on attention-based decoders to map AMR node to English token sequences. Instead of linearizing AMR, we directly encode its graph structure and delegate traversal to the decoder. To enforce a sentence-aligned graph traversal and provide local graph context, we predict transition-based parser actions in addition to English words. We present two model variants: one generates parser actions prior to words, while the other interleaves actions with words.
EVICES AGAINST C YBER-ATTACKS

Internet of Things (IoT) is the interconnection of heterogeneous smart devices through the Internet with diverse application areas. The huge number of smart devices and the complexity of networks has made it impossible to secure the data and communication between devices. Various conventional security controls are insufficient to prevent numerous attacks against these information-rich devices. Along with enhancing existing approaches, a peripheral defence, Intrusion Detection System (IDS), proved efficient in most scenarios. However, conventional IDS approaches are unsuitable to mitigate continuously emerging zero-day attacks. Intelligent mechanisms that can detect unfamiliar intrusions seems a prospective solution. This article explores popular attacks against IoT architecture and its relevant defence mechanisms to identify an appropriate protective measure for different networking practices and attack categories. Besides, a security framework for IoT architecture is provided with a list of security enhancement techniques.
Epoch-wise label attacks for robustness against label noise

The current accessibility to large medical datasets for training convolutional neural networks is tremendously high. The associated dataset labels are always considered to be the real"ground truth". However, the labeling procedures often seem to be inaccurate and many wrong labels are integrated. This may have fatal consequences on the performance of both training and evaluation. In this paper, we show the impact of label noise in the training set on a specific medical problem based on chest X-ray images. With a simple one-class problem, the classification of tuberculosis, we measure the performance on a clean evaluation set when training with label-corrupt data. We develop a method to compete with incorrectly labeled data during training by randomly attacking labels on individual epochs. The network tends to be robust when flipping correct labels for a single epoch and initiates a good step to the optimal minimum on the error surface when flipping noisy labels. On a baseline with an AUC (Area under Curve) score of 0.924, the performance drops to 0.809 when 30% of our training data is misclassified. With our approach the baseline performance could almost be maintained, the performance raised to 0.918.
Reliability and validity of the Turkish version of the CDC HRQOL-4 scale in patients with chronic low back pain

Objective: This study investigates reliability and validity of Turkish version of CDC Core Healthy Days Measures assessing health related quality of life (CDC HRQOL-4) in chronic low back pain (CLBP) patients. Methodology: One hundred eighty nine CLBP patients and 117 healthy controls participated. All respondents filled the following scales; the CDC HRQOL-4, Rolland Morris Questionnaire (RMQ), and the Hospital Anxiety and Depression Scale (HAD). Results: Cronbach’s alpha of CDC HRQOL-4-items in CLBP patients was 0.69. Of 57.1% CLBP patients and 13.7% healthy controls defined their health status as fair or poor. The number of physically and mentally unhealthy days, and activity limitation days was found to be higher in the CLBP patients than the healthy controls (p<0.05). The CLBP patients with fair or poor health reported more physically unhealthy days, mentally unhealthy days, and activity limitation days than the CLBP patients with excellent, very good, or good health (p<0.05). Correlation coefficients between physically unhealthy days (r=0.30) and activity limitation days (r=0.22), and RMQ scores were significant, but low in magnitude. Moderate correlations between mentally unhealthy days and HAD scores (r=0.41 for anxiety; r=0.39 for depression) were found. Conclusion: The results of this study indicate that the Turkish version of the CDC HRQOL-4 is a short, reliable and valid tool to assess HRQOL in CLBP patients.
Ontogenic development of drug-metabolizing enzymes in male chicken liver

The ontogenic study of the hepatic biotransformation enzymes revealed the early development of both oxidative and conjugative enzymes in male chickens ranging in age from 3 to 12 weeks. Although the rate of microsomal cytochrome P450 reactions progressively increased during the first 9 weeks, it decreased thereafter. Furthermore, the proteins revealed by the antibodies to anti-cytochrome P450 1A2, 2B4, 2C7, and 3A4 appeared to be constitutively expressed. Hepatic monooxygenases were characterized by different developmental patterns. The demethylase activities increased progressively up to 9 weeks, then they declined, in 12 weeks reaching the activity level observed in 3-week-old chickens. In contrast, alkoxyresorufin O-dealkylases and benzopyrene hydroxylase activities continued to increase with age. Significant variability was noted for aniline hydroxylase. Among conjugation enzymes, UDP-glucuronyltransferase towards p-nitrophenol and isoniazid N-acetyltransferase activities increased with the age of the fowl, but with different profiles. Concerning glutathione S-transferase accepting 1-chloro-2,4-dinitrobenzene or 1,2-dichloro-4-nitrobenzene, the chickens aged from 3 to 9 weeks were less well developed in this enzyme than 12-week-old ones.
In vitro evaluation of dental bleaching effectiveness using hybrid lights activation

Purpose: The aim of this in vitro study was to evaluate whether using different types of light activation during the in-office bleaching agent technique increases the effectiveness of the dental bleaching procedure by measuring the color change in teeth. Methods: From 60 extracted bovine incisor teeth, specimen sizes were standardized and dentin was conditioned by immersion in 38% phosphoric acid for 15 s. Following this procedure, the samples were placed in a water bath with ultrasound for 20 min and then immersed in a 25% coffee solution for a two-week period. The dentin was polished with a felt disc and aluminum oxide paste and finally sealed with colorless nail polish. Specimens were randomly divided into five groups, and their original color was measured using the EasyShade (VITA) spectrophotometer. All specimens received three applications of the bleaching agent Opalescence Xtra-Boost (Ultradent) during a period of 15 min each. Group 1 did not receive light activation, Group 2 was activated with a Halogen light (15 min), Group 3 was activated with a blue hybrid LEDs and a laser (15 min), Group 4 was activated with light from a green LED and a laser (15 min) and Group 5 was activated with a red laser (15 min). Tooth color was measured again after performing the various bleaching techniques on all specimens. The resulting data on color variations ΔE, Δa*, Δb* and ΔL*, and the color variations referenced on the Vita Classical scale were subjected to ANOVA, Tukey and Dunn tests (α=5%). Results: The bleaching performance of 38% hydrogen peroxide was affected by the light source used; color reduction was observed for the blue LED and halogen lights, and quantitative assessments of tooth color measured by spectrophotometer and matched to the Vita Classical color scale arrived at similar results in all experimental groups. Conclusions: The type of hybrid lights used interferes in the efficiency of the bleaching agent.
Uso de modelação matemática para projeto de câmaras mecanizadas de floculação em série em estações de tratamento de água

The existing methodology in the literature to optimize the velocity gradients in continuous flow completely mixed reactors using batch test data (static reactors) is based on mathematical models that describe the flocculation kinetics. Since this methodology has been shown to be inconsistent, as observed by several researchers, this work was carried out in order to propose a rational methodology to optimize the static reactors experimental data to obtain the design parameters of mechanized flocculation systems for water treatment plants.
Women Officers Working in Men's Prisons

New Zealand was a late starter in the international trend towards employing female prison officers to work in men’s prisons. Even after the first such officer was appointed in 1985, resistance to the idea continued in some quarters. This paper examines the recent history of New Zealand women’s involvement in men’s prisons and the debates that ensued. As will be seen, the fears of male prison officers that inmates would endanger women’s safety proved largely unfounded, and the principal obstacle to women’s integration was not the inmates but some officers themselves. Nonetheless, certain issues, particularly the risk of females entering into inappropriate relationships with their male charges, remain. The paper discusses the advantages and disadvantages of having women officers working in a front-line capacity with male prison inmates, and how some of the problems have been addressed.
Ethnomethodological ethnography and its application in nursing

Abstract This paper examines the use of a qualitative research methodology, ethnomethodological ethnography that has had little application within nursing, whether in the United Kingdom or elsewhere. This methodology is concerned with describing how members of a social group perceive, define and classify the ways that they perform their daily activities and what meanings they assign to these activities. Ethnomethodological ethnography analyses the everyday methods people use to construct and sustain the typical activities in their cultural world, that is, their ‘sense assembly equipment’. This enables them to act in ways that are congruent with their culturally learnt attitudes. Although this paper focuses on describing ethnomethodological ethnography, examples of its use in a study of nursing practice are provided from a doctoral study that explored the everyday methods military nurses used to rationalise their post-operative pain assessment decisions. From the experiences of this study, it is argued that ethnomethodological ethnography is a valuable methodology for investigating how nurses rationalise their decisions within nursing practice.
Enhancement of Argon Laser Effect on Dissolution and Loss of Human Enamel

ABSTRACT Previous studies have recorded the reduction of caries-like lesions in extracted human teeth that have been irradiated with CO2 laser. Other studies have shown a decrease in dissolution of enamel that has been irradiated with Argon laser. This study was conducted to see if there are additive effects between argon laser irradiation and those of chemical inhibitors, ethane-l-hydroxy-l,l-diphosphonic acid (EHDP) and dodecylamine HC1 (DAC) on the loss of tooth structure due to demineralization of dental enamel. The amount of demineralization was determined in a rotating disk assembly (0.1 M acetate buffer, pH 4.5) for 24 hr and the results determined and plotted against the nonlased control using microradiography and computerized imaging. The amount of tooth structure lost to demineralization in 4.5 pH acid bath in a 24-hr period was reduced from approximately 140 μm to nearly zero when Argon lased enamel was exposed to DAC or EHDP.
Synthesen in der Lumiflavinreihe IV

Starting from lumiflavine and its 2-thio-analogue, the leukoflavine nucleus was obtained and stabilized by reductive acylation. The acyl-leuko-compounds seem to exhibit the possibility of substitution reactions in 2- and 4-positions. Several new lumiflavines were obtained, e. g. 4-thiolumiflavine and 2-desoxylumiflavine. The latter shows rather peculiar oxido-reductive properties which are discussed.