Miracle-dz/UniFAR-FTUs huggingface dataset:
Tropical Clemens-Schmid sequence and existence of tropical cycles with a given cohomology class

This is a sequel to our work in tropical Hodge theory. Our aim here is to prove a tropical analogue of the Clemens-Schmid exact sequence in asymptotic Hodge theory. As an application of this result, we prove the tropical Hodge conjecture for smooth projective tropical varieties which are rationally triangulable. This provides a partial answer to a question of Kontsevich who suggested the validity of the tropical Hodge conjecture could be used as a test for the validity of the Hodge conjecture.
Biological production of methane from energy crops

Laboratory studies at the University of Missouri‐Rolla have demonstrated the feasibility of producing methane by anaerobic digestion of various of crop materials, such as grasses and corn stalks. These studies indicate that up to 6.0 f3methane are produced/b crop material destroyed. Preliminary design and economic studies of a large methane plant show that the reactors represent the largest cost item and that efforts should be concentrated on defining reaction kinetics and reactor design. A process to produce 50 M̄ f3methane/day is described, and the preliminary design and economics are analyzed.
Fibrations in semitoric and generalized complex geometry

Abstract This paper studies a class of singular fibrations, called self-crossing boundary fibrations, which play an important role in semitoric and generalized complex geometry. These singular fibrations can be conveniently described using the language of Lie algebroids. We will show how these fibrations arise from (nonfree) torus actions, and how to use them to construct and better understand self-crossing stable generalized complex four-manifolds. We moreover show that these fibrations are compatible with taking connected sums, and use this to prove a singularity trade result between two types of singularities occurring in these types of fibrations (a so-called nodal trade).
Variational Determinant Estimation with Spherical Normalizing Flows

This paper introduces the Variational Determinant Estimator (VDE), a variational extension of the recently proposed determinant estimator discovered by arXiv:2005.06553v2. Our estimator significantly reduces the variance even for low sample sizes by combining (importance-weighted) variational inference and a family of normalizing flows which allow density estimation on hyperspheres. In the ideal case of a tight variational bound, the VDE becomes a zero variance estimator, and a single sample is sufficient for an exact (log) determinant estimate.
Higher order obstructions to the desingularization of Einstein metrics

We find new obstructions to the desingularization of compact Einstein orbifolds by smooth Einstein metrics. These new obstructions, specific to the compact situation, raise the question of whether a compact Einstein 4-orbifold which is limit of Einstein metrics bubbling out Eguchi-Hanson metrics has to be Kähler. We then test these obstructions to discuss if it is possible to produce a Ricci-flat but not Kähler metric by the most promising desingularization configuration proposed by Page in 1981. We identify 84 obstructions which, once compared to the 57 degrees of freedom, indicate that almost all flat orbifold metrics on T/Z2 should not be limit of Ricci-flat metrics with generic holonomy while bubbling out Eguchi-Hanson metrics. Perhaps surprisingly, in the most symmetric situation, we also identify a 14-dimensional family of desingularizations satisfying all of our 84 obstructions.
Very-high-energy Emission and Cascade Radiation of Gamma-Ray Burst Afterglows: Homogeneous versus Wind External Media

Recent detection of sub-TeV emission from gamma-ray bursts (GRBs) represents a breakthrough in the GRB study. The multiwavelength data of the afterglows of GRB 190114C support the synchrotron self-Compton (SSC) origin for its sub-TeV emission. We present a comparative analysis on the SSC emission of GRB afterglows in the homogeneous and wind environments in the framework of the forward shock model. The γ γ absorption of very-high-energy photons due to pair production within the source and the Klein–Nishina effect on the inverse Compton scattering are considered. Generally a higher SSC flux is expected for a larger circum-burst density due to a larger Compton parameter, but meanwhile the internal γ γ absorption is more severe for sub-TeV emission. The flux ratio between the SSC component and the synchrotron component decreases more quickly with time in the wind medium case than in the homogeneous density medium case. The light curves of the SSC emission are also different for the two types of media. We also calculate the cascade emission resulting from the absorbed high-energy photons. In the ISM environment with n ≳ 1 cm−3, the cascade synchrotron emission could be comparable to the synchrotron emission of the primary electrons in the optical band, which may flatten the optical afterglow light curve at an early time (t < 1 hr). In the wind medium with A * ≳ 0.1, the cascade emission in the eV–GeV band is comparable or even larger than the emission of the primary electrons at the early time.
What if a specific neutrinoless double beta decay is absent?

We consider the seesaw model with two right-handed neutrinos, $N_1$ and $N_2$, the masses of which are hierarchical, and investigate their contribution to the neutrinoless double beta ($0 \nu \beta \beta$) decay. Although the lepton number is broken by the Majorana masses of right-handed neutrinos, such decay processes can be absent in some cases. We present a possibility where the lighter $N_1$ gives a destructive contribution to the decay of active neutrinos by choosing the specific mixing elements of $N_1$, while $N_2$ is sufficiently heavy not to contribute to the $0 \nu \beta \beta$ decay. In this case the mixing elements of $N_1$ in the charged current interaction are determined by its mass and the Majorana phase of active neutrinos. We then study the impacts of such a possibility on the direct search for $N_1$. In addition, we discuss the consequence of the case when the $0 \nu \beta \beta$ decay in one specific nucleus is absent.
Possible Evidence of Hydrogen Emission in the First-overtone and Multimode RR Lyrae Variables

The nature of shock waves in nonfundamental mode RR Lyrae stars remains a mystery because of limited spectroscopic observations. We apply a pattern recognition algorithm on spectroscopic data from SDSS and LAMOST and report the first evidence of hydrogen emission in first-overtone (RRc) and multimode (RRd) RR Lyrae stars showing the “first apparition,” which is the most prominent observational characteristic of shock in RR Lyrae variables. We find 10 RRc stars in SDSS, 10 RRc stars in LAMOST, and 3 RRd stars in LAMOST that show blueshifted Balmer emissions. The emission features possibly indicate the existence of shock waves. We calculate the radial velocities of the emission lines, which are related to the physical conditions occurring in the radiative zone of shock waves. Using photometric observations from ZTF, we present a detailed light-curve analysis for the frequency components in one of our RRd stars with hydrogen emission, RRdl3, for possible modulations. With the enormous volume of upcoming spectral observations of variable stars, our study raises the possibility of connecting the unexplained Blazhko effect to shock waves in nonfundamental mode RR Lyrae stars.
Dust polarized emission observations of NGC 6334

[Abridged] Filaments and hubs have received special attention recently thanks to studies showing their role in star formation. While the column density and velocity structures of both filaments and hubs have been studied, their magnetic fields (B-field) are not yet characterized. We aim to understand the role of the B-field in the dynamical evolution of the NGC 6334 hub-filament network. We present new observations of the dust polarized emission at 850$\mu$m towards NGC 6334 obtained with the JCMT/POL-2. We study the distribution and dispersion of the polarized intensity ($PI$), the polarization fraction ($PF$), and the B-field angle ($\theta_{B}$). We derive the power spectrum of the intensity and $\theta_{B}$ along the ridge crest. Our analyses show a complex B-field structure when observed over the whole region ($\sim10$ pc), however, at smaller scales ($\sim1$ pc), $\theta_{B}$ varies coherently along the filaments. The observed power spectrum of $\theta_{B}$ can be well represented with a power law function with a slope $-1.33\pm0.23$, which is $\sim20\%$ shallower than that of $I$. This result is compatible with the properties of simulated filaments and may indicate the processes at play in the formation of filaments. $\theta_{B}$ rotates from being mostly perpendicular to the filament crests to mostly parallel as they merge with the hubs. This variation of $\theta_{B}$ may be tracing local velocity flows of matter in-falling onto the hubs. Our analysis suggests a variation of the energy balance along the crests of these filaments, from magnetically critical/supercritical at their far ends to magnetically subcritical near the hubs. We detect an increase of $PF$ towards the high-column density star cluster-forming hubs that may result from the increase of grain alignment efficiency due to stellar radiation from the newborn stars.
On the Conditions of Absorption Property for Morphological Opening and Closing

This paper aims to establish the theoretical foundation for shift inclusion in mathematical morphology. In this paper, we prove that the morphological opening and closing concerning structuring elements of shift inclusion property would preserve the ordering of images, while this property is important in granulometric analysis and related image processing tasks. Furthermore, we proposed a systematic way, called the decomposition theorem for shift inclusion, to construct sequences of structuring elements with shift inclusion property. Moreover, the influences of the image domain are discussed and the condition named weak shift inclusion is defined, which is proved as an equivalent condition for ensuring the order-preserving property.
Graph Theory in the Classification of Information Systems

Risk classification plays an important role in many regulations and standards. However, a general method that provides an optimal classification has not been proposed yet. Also, the criteria of optimality are not defined in these regulations. In this work, we will propose a mathematical model that is sufficient to describe this problem, and we also propose an algorithm that classifies graph vertices based on their risk value in polynomial time.
Assessment of lead and cadmium residues in farmed fish in Machakos and Kiambu counties, Kenya

Lead (Pb) and cadmium (Cd) concentrations were determined in muscle, gonad, liver and brain of tilapia fish caught from fish ponds in Machakos and Kiambu counties in Kenya. A total of 217 fish samples were randomly sampled from the two counties. Acid digestion method and atomic absorption spectrophotometer were used for analysis. Heavy metal concentrations varied significantly depending on the type of tissue analyzed. Generally, the highest concentration of Pb was detected in brain and the liver. Fish organs contained Pb in the following order: brain > liver > muscle > gonad, while Cd followed the order: brain > liver > gonad > muscle. Kiambu county recorded higher concentration of the studied heavy metals compared to Machakos county although statistically there was no difference. Lead and Cd content in both counties studied exceeded the maximum allowable limit. The study recommended controlling industrial and agricultural effluents into surface water and proper sitting of ponds to minimize the risk of contamination of farmed fish by heavy metals.
Sentence-Based Model Agnostic NLP Interpretability

Today, interpretability of Black-Box Natural Language Processing (NLP) models based on surrogates, like LIME or SHAP, uses word-based sampling to build the explanations. In this paper we explore the use of sentences to tackle NLP interpretability. While this choice may seem straight forward, we show that, when using complex classiﬁers like BERT, the word-based approach raises issues not only of computational complexity, but also of an out of distribution sampling, eventually leading to non founded explanations. By using sentences, the altered text remains in-distribution and the dimensionality of the problem is reduced for better ﬁdelity to the black-box at comparable computational complexity.
Transcriptome profiling reveals Silibinin dose-dependent response network in non-small lung cancer cells

Silibinin (SIL), a natural flavonolignan from the milk thistle (Silybum marianum), is known to exhibit remarkable hepatoprotective, antineoplastic and EMT inhibiting effects in different cancer cells by targeting multiple molecular targets and pathways. However, the predominant majority of previous studies investigated effects of this phytocompound in a one particular cell line. Here, we carry out a systematic analysis of dose-dependent viability response to SIL in five non-small cell lung cancer (NSCLC) lines that gradually differ with respect to their intrinsic EMT stage. By correlating gene expression profiles of NSCLC cell lines with the pattern of their SIL IC50 response, a group of cell cycle, survival and stress responsive genes, including some prominent targets of STAT3 (BIRC5, FOXM1, BRCA1), was identified. The relevancy of these computationally selected genes to SIL viability response of NSCLC cells was confirmed by the transient knockdown test. In contrast to other EMT-inhibiting compounds, no correlation between the SIL IC50 and the intrinsic EMT stage of NSCLC cells was observed. Our experimental results show that SIL viability response of differently constituted NSCLC cells is linked to a subnetwork of tightly interconnected genes whose transcriptomic pattern can be used as a benchmark for assessment of individual SIL sensitivity instead of the conventional EMT signature. Insights gained in this study pave the way for optimization of customized adjuvant therapy of malignancies using Silibinin.
Muscle strength and inflammatory response to the training load in rowers

Background Regular exercise leads to changes in muscle metabolism. The consequence of this is the adaptation to higher training loads.The aim of this study was to evaluate biomechanical and biochemical parameters describing the functions of skeletal muscles in periods when changes in training forms were introduced. Methods Seventeen male sweep-oar rowers, members of the Polish national rowing team, participated. The study was carried out at the beginning and at the end of the preparatory period. In the first and second examination measurements of torques of selected muscle groups and blood biochemical analysis were performed. Results There was observed a statistically significant decrease in the relative global force of the right lower limb between both terms of examination. A statistically significant increase in maximum torque was found for torso flexors. In the case of muscles responsible for torso rotation, a statistically significant decrease in the torque values of right torso rotators was observed. A significant difference was found with respect to creatine kinase activity, total testosterone concentration, total testosterone to cortisol ratio and total phenolics concentration (p < 0.05). Conclusion The study shows that the rowers’ training should be more focused on building the strength of lower limbs to prevent the overload of lumbar spine and that the amount of force developed may be significantly affected by the antioxidant potential of rowers.
Non-ambient X-ray diffraction residual stress analysis of thin films: tracing nanosize-related effects on thermoelastic constants and identifying sources of residual stresses

The stress evolutions at non-ambient temperatures in Ni and Pd layers (the thickness of each metal layer was 50 nm) were investigated employing in-situ X-ray diffraction measurements in a temperature range between 173 and 523 K. Stress determinations were performed by analysing the X-ray diffraction data according to the sin2ψ method on the basis of the crystallite group variant. The stress evolution in the Ni layer was correlated with the change of its coherently diffracting domain size and its microstrain with temperature. The advantage of measurements at temperatures below ambient to distinguish the thermal stresses from the effects of stress relaxation and emerging secondary stresses, arising from thermally activated processes (such as grain growth), is highlighted in this work for the first time. The possibility of using the in-situ X-ray diffraction stress measurement to obtain coefficients of thermal expansion and thermoelastic slopes of thin films (with nanosized grains) is discussed in detail.
The effect of decay and lexical uncertainty on processing long-distance dependencies in reading

To make sense of a sentence, a reader must keep track of dependent relationships between words, such as between a verb and its particle (e.g. turn the music down). In languages such as German, verb-particle dependencies often span long distances, with the particle only appearing at the end of the clause. This means that it may be necessary to process a large amount of intervening sentence material before the full verb of the sentence is known. To facilitate processing, previous studies have shown that readers can preactivate the lexical information of neighbouring upcoming words, but less is known about whether such preactivation can be sustained over longer distances. We asked the question, do readers preactivate lexical information about long-distance verb particles? In one self-paced reading and one eye tracking experiment, we delayed the appearance of an obligatory verb particle that varied only in the predictability of its lexical identity. We additionally manipulated the length of the delay in order to test two contrasting accounts of dependency processing: that increased distance between dependent elements may sharpen expectation of the distant word and facilitate its processing (an antilocality effect), or that it may slow processing via temporal activation decay (a locality effect). We isolated decay by delaying the particle with a neutral noun modifier containing no information about the identity of the upcoming particle, and no known sources of interference or working memory load. Under the assumption that readers would preactivate the lexical representations of plausible verb particles, we hypothesised that a smaller number of plausible particles would lead to stronger preactivation of each particle, and thus higher predictability of the target. This in turn should have made predictable target particles more resistant to the effects of decay than less predictable target particles. The eye tracking experiment provided evidence that higher predictability did facilitate reading times, but found evidence against any effect of decay or its interaction with predictability. The self-paced reading study provided evidence against any effect of predictability or temporal decay, or their interaction. In sum, we provide evidence from eye movements that readers preactivate long-distance lexical content and that adding neutral sentence information does not induce detectable decay of this activation. The findings are consistent with accounts suggesting that delaying dependency resolution may only affect processing if the intervening information either confirms expectations or adds to working memory load, and that temporal activation decay alone may not be a major predictor of processing time.
CO2-Reforming of Methane on Supported Rh and Ir Catalysts

The effect of catalyst structure on CO{sub 2} reforming of methane has been studied in the temperature range 550-850{degrees}C with oxide-supported Rh and Ir catalysts under conditions of reaction rate control. It is found that the rate of reaction expressed per unit metal surface area is constant over a wide dispersion range. There is no detectable effect of the pore structure or nature of the support on the reaction rate. By variation of feed composition through addition of steam or oxygen the H{sub 2}/CO ratio in the product could be varied. 32 refs., 6 figs., 5 tabs.
Determination of inhibition effects of various imidazole derivatives on copper corrosion in 0·1M HCl media

In the present study the inhibitive behaviour of 1H-imidazole, 1-methyl imidazole, imidazolidin-2-one, 4-(imidazole-1-yl)acetophenone, 4-(imidazole-1-yl) phenol and L-hystidine on the corrosion of copper in 0·1 M HCl has been investigated by potentiodynamic polarisation and polarisation resistance techniques. Except for 2-imidazolidone, the tested imidazole derivatives were found to behave as cathodic inhibitors. 1-methyl imidazole, 4-(imidazole-1-yl) acetophenone, 4-(imidazole-1-yl) phenol and L-hystidine were adsorbed on copper surface according to Temkin isotherm model. By using semi-empirical quantum chemical methods, physical parameters such as charge on the heteroatoms of imidazole derivatives q n, energies of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and dipole moments were calculated. Possible correlations between these calculated physical parameters and inhibitor efficiencies were considered. Finally, the mechanistic information relating to the inhibition process was elucidated.
Spintronics

Conventional MOS integrated circuits and systems suffer serve power and scalability challenges as technology nodes scale into ultra-deep-micron technology nodes (e.g., below 40nm). Both static and dynamic power dissipations are increasing, caused mainly by the intrinsic leakage currents and large data traffic. Alternative approaches beyond charge-only-based electronics, and in particular, spin-based devices, show promising potential to overcome these issues by adding the spin freedom of electrons to electronic circuits. Spintronics provides data non-volatility, fast data access, and low-power operation, and has now become a hot topic in both academia and industry for achieving ultra-low-power circuits and systems. The ITRS report on emerging research devices identified the magnetic tunnel junction (MTJ) nanopillar (one of the Spintronics nanodevices) as one of the most promising technologies to be part of future micro-electronic circuits. In this review we will give an overview of the status and prospects of spin-based devices and circuits that are currently under intense investigation and development across the world, and address particularly their merits and challenges for practical applications. We will also show that, with a rapid development of Spintronics, some novel computing architectures and paradigms beyond classic Von-Neumann architecture have recently been emerging for next-generation ultra-low-power circuits and systems.
Scranvas: Gamified Forum for Amateur Designers to Share Creative Work and Generate Constructive Feedback

Feedback is important for cultivating creativity. Constructive feedback on design is crucial for helping design students and amateur designers iterate towards better solutions. However most of the current platforms don't promote honest design feedback and are primarily used only for self-promotion. This paper proposes Scranvas, a community for students and non-experts to encourage sharing of creative work and generate constructive feedback. Users interpret the designs based on the context and goals stated by the designer and share feedback through annotations.