Miracle-dz/UniFAR-FTUs huggingface dataset:
Electron spin decoherence of single nitrogen-vacancy defects in diamond

We present a theoretical analysis of the electron spin decoherence in single Nitrogen-Vacancy defects in ultra-pure diamond. The electron spin decoherence is due to the interactions with Carbon-13 nuclear spins in the diamond lattice. Our approach takes advantage of the low concentration (1.1%) of Carbon-13 and their random distribution in the diamond lattice by an algorithmic aggregation of spins into small, strongly interacting groups. By making use of this \emph{disjoint cluster} approach, we demonstrate a possibility of non-trival dynamics of the electron spin that can not be described by a single time constant. This dependance is caused by a strong coupling between the electron and few nuclei and results, in particular, in a substantial echo signal even at microsecond time scales. Our results are in good agreement with recent experimental observations.
Piezoelectric wind energy harvesting from vortex- induced vibrations of an elastic beam

In the present study, the performance of a cylinder-based piezoelectric wind energy harvester attached to an elastic beam is numerically simulated. The wind (cid:13)ow perpendicular to the beam axis causes an oscillatory aerodynamic force exerted on the beam tip. The beam and the piezoelectric layer are modeled as elastic continuous bodies, and the continuum governing equations of the solid and piezoelectric layers are extracted. Moreover, the induced lift force by the vortex shedding downstream of the cylinder is estimated by the modi(cid:12)ed van der Pol wake oscillator equation. The cantilever mode shapes and the Galerkin method are applied to solve the three transient and coupled equations of elastic de(cid:13)ection, electrical resistance, and (cid:13)uid force. Besides verifying the accuracy of the modi(cid:12)ed van der Pol equation, a moving object Computational Fluid Dynamics (CFD) simulation is also conducted. The e(cid:11)ects of oscillator length, cylinder diameter, resistance load, structure and piezoelectric thickness as well as the wind speed on the produced power are investigated. According to the obtained results, upon increasing the cylinder diameter from 0.05 m by 100, 200, and 300%, the output power is increased by 219, 801, and 1502% at a wind speed of 5 m/s.
What’s different about loans? An empirical analysis of credit spreads on public debt and bank facilities

Understanding the determinants of credit spreads has always been an important objective of academic researchers, regulators and practitioners alike. While extensive research has been produced on bonds and loans separately, few studies have analyzed those two classes of debt instruments jointly. The aim of this study is to draw an empirical comparison between the determinants of bond and loan spreads, unifying two streams of research that have grown richer and livelier over the latest years. The empirical analysis is based on a sample of 7,926 Eurobonds and 5,469 syndicated loans originated between 1991 and 2003. Many interesting results emerge from the empirical analysis. First, while spreads increase as ratings worsen for both bonds and loans, the spread/rating link is quite steeper for the former, while the risk premium required by banks on low-quality loans appears much milder than the one demanded by private investors in the bond market. Second, the maturity premium looks much larger for bank facilities than for bonds (where long maturities are more usual than in the syndicated loan market). Third, while larger bond issues tend to be associated with higher spreads, syndicated loans’ spreads appear to decrease as size increases: besides liquidity issues, this may reflect the scale economies implied in information-gathering, screening and monitoring costs which are typically associated with lending. Fourth, while subordinated exposures have to pay more than senior ones for both bonds and loans, this is especially true for the latter, and may reflect the fact that senior syndicated loans enjoy higher recovery rates than bonds. Finally, for both bonds and loans, secured exposures appear to pay a higher spread than unsecured ones, consistently with the results of a wide stream of literature.
Variational Bayesian Image Restoration with Transformation Parameter Estimation

: Image restoration is essential for high-quality photography and used in many applications. Its objective is to estimate a clean image from one or more degraded images a ﬀ ected by problem-speciﬁc transformation with an unknown parameter. Traditionally, the estimation of this transformation parameter has limited the e ﬀ ectiveness of restoration, since it can be unstable in the presence of severe or complex degradation. In this work, we overcome this di ﬃ culty by estimating multiple parameters simultaneously via stable joint inference enabled by variational Bayes. Speciﬁcally, we developed novel methods for three problems of restoration: multiframe denoising, deblurring, and devignetting. The established methodology can address various restoration problems in a uniﬁed Bayesian framework, and also achieves high quality restoration for a wide range of images owing to stable and fully automatic parameter tuning, thereby extending the real-world applicability of restoration.
Fresh pasta filata cheeses: Composition, role, and evolution of the microbiota in their quality and safety

With a global market of around $55 billion (in US dollars; i.e. around the 57% of the global cheese mar-ket), pasta filata cheeses sales are rising approximately 2% per year worldwide and are expected to further increase to $65.01 billion by 2028. Among these groups of cheeses, fresh pasta filata cheeses, such as mozzarella and fior di latte, are the most consumed. Herein, we provide an overview of fresh pasta filata cheeses, their commodity-related and technological aspects, focusing on the composition, the role, and evolution of their microbiota along the dairy chain.
Main Manuscript for 1 Reduction of free-roaming cat population requires high-intensity neutering 2 in spatial contiguity to mitigate compensatory effects 3

(TNR)," which is considered more humane. Despite the extensive application of TNR, a long-term controlled study was never performed to test its effectiveness. We present a uniquely designed controlled field 2 experiment for examining TNR effectiveness. The study was performed over a twelve- year period, divided into pre-intervention, mixed- and full-intervention phases, and spanned a 20Km 2 urban area. Trends of cat, intact-female, and kitten counts, cat reproduction, and carcass reports were compared among study phases and areas with 38 different neutering intensities. The cat population increased during the first two study 39 phases and did not decline in highly neutered populations, presumably due to cat 40 immigration. Expansion of high-intensity neutering to the entire city in the full- 41 intervention phase (>70% neutering percentage) reversed cat population growth, reaching 42 an annual ca. 7% reduction. This population reduction was limited by a rebound increase 43 in cat reproduction and longevity. We conclude that cat population management by TNR 44 should be performed in high-intensity, continuously, and in geographic contiguity to 45 enable population reduction. To enhance management effectiveness and mitigate 46 compensatory effects, we recommend further evaluating an integrated strategy that 47 combines TNR with complementary methods (e.g., vital resource regulation, ill cat 48 euthanasia, and adoption).
Ergodicity and central-limit theorem in systems with long-range interactions

In this letter we discuss the validity of the ergodicity hypothesis in theories of violent relaxation in long-range interacting systems. We base our reasoning on the Hamiltonian mean-field model and show that the lifetime of quasi-stationary states resulting from the violent relaxation does not allow the system to reach a complete mixed state. We also discuss the applicability of a generalization of the central-limit theorem. In this context, we show that no attractor exists in distribution space for the sum of velocities of a particle other than the Gaussian distribution. The long-range nature of the interaction leads in fact to a new instance of sluggish convergence to a Gaussian distribution.
Concepts Through Time: Tracing Concepts in Dutch Newspaper Discourse (1890-1990) using Word Embeddings

In this paper, we use a new technique, called Concepts Through Time (CTT), to trace concepts in newspaper discourse. CTT makes use of sequential semantic spaces to follow semantic shifts of concepts diachronically. The semantic spaces are based on the extensive digitized newspaper corpus of the Dutch National Library. 1 As part of our approach, concepts are modeled as words related to each other in a semantic space. A key aspect of CTT is that the vocabulary used in the debate on a concept may change over time. In fact, the set of words used to discuss a particular concept might not show any overlap at all between different periods of time. As such, our method bears a resemblance to the rhizomatic structure as described by philosopher Gilles Deleuze. The conceptual implication of this method approximates the traditional scholarly methods of conceptual history. We test our method through three case studies: consumerism, globalization, and economic models. These domains are inextricably linked to the manifestation of modernization and
Backward stochastic differential equations and partial differential equations with quadratic growth

We provide existence, comparison and stability results for one-dimensional backward stochastic differential equations (BSDEs) when the coefficient (or generator) F(t, Y, Z) is continuous and has a quadratic growth in Z and the terminal condition is bounded. We also give, in this framework, the links between the solutions of BSDEs set on a diffusion and viscosity or Sobolev solutions of the corresponding semilinear partial differential equations.
MHV diagrams in twistor space and the twistor action

MHV diagrams give an efficient Feynman diagram-like formalism for calculating gauge theory scattering amplitudes on momentum space. Although they arise as the Feynman diagrams from an action on twistor space in an axial gauge, the main ingredients were previously expressed only in momentum space and momentum twistor space. Here we show how the formalism can be elegantly derived and expressed entirely in twistor space. This brings out the underlying superconformal invariance of the framework (up to the choice of a reference twistor used to define the axial gauge) and makes the twistor support transparent. Our treatment is largely independent of signature, although we focus on Lorentz signature. Starting from the N = 4 super-Yang-Mills twistor action, we obtain the propagator for the anti-holomorphic Dolbeault-operator as a delta function imposing collinear support with the reference twistor defining the axial gauge. The MHV vertices are also expressed in terms of similar delta functions. We obtain concrete formulae for tree-level NkMHV diagrams as a product of MHV amplitudes with an R-invariant for each propagator; here the R-invariant manifests superconformal as opposed to dual-superconformal invariance. This gives the expected explicit support on k + 1 lines linked by k further lines associated to the propagators. The R-invariants arising correspond to those obtained in the dual conformal invariant momentum twistor version of the formalism, but differences arise in the specification of the boundary terms. Surprisingly, in this framework, some finite loop integrals can be performed as simply as those for tree diagrams.
Bright UV-C Phosphors with Excellent Thermal Stability—Y1−xScxPO4 Solid Solutions

The structural and luminescence properties of undoped Y1−xScxPO4 solid solutions have been studied. An intense thermally stable emission with fast decay (τ1/e ~ 10−7 s) and a band position varying from 5.21 to 5.94 eV depending on the Sc/Y ratio is detected and ascribed to the 2p O-3d Sc self-trapped excitons. The quantum yield of the UV-C emission, also depending on the Sc/Y ratio, reaches 34% for the solid solution with x = 0.5 at 300 K. It is shown by a combined analysis of theoretical and experimental data that the formation of Sc clusters occurs in the solid solutions studied. The clusters facilitate the creation of energy wells at the conduction band bottom, which enables deep localization of electronic excitations and the creation of luminescence centers characterized by high quantum yield and thermal stability of the UV-C emission.
NON-INVASIVE DATA ACQUISITION FOR USER MODELING

: One of the most impending drawbacks of modern information technology and communication devices is the problem of user interfacing. The focus of the research community to tackle this problem is almost exclusively set to the concept of personalization based on user modeling procedures. The major difficulty of user modeling procedures is the required input data about the modeled user. Studies and practical experiences show that, on one hand, the efficiency of user modeling relies on acquired data about the user, and on the other hand, it is extremely irritating for user to constantly provide such data about her or his feelings and behavior. Therefore there is a need for non-intrusive and non-irritating data collection about the user. There are several approaches such us distributed sensors and real time analysis of video capturing the user’s behavior with the intention of identifying specific information about user’s behavior. The problem statement of noninvasive data acquisition for user modeling along with a typical system architecture will be presented in the paper. A set of unavoidable information processing techniques in this context will be introduced. The proposed approach will be further detailed by data acquisition based on a real time video analysis and higher order post processing of gathered user data. A major part of the paper is focused on post processing of user data in terms of geometrical, topological and logical analysis with the aim of achieving an effective user model.
Treatment and Prognosis of Aphasia after Stroke

Stroke is the second prominent cause of death in the world and the first in China with 1/3 of the survivors presenting with post-stroke aphasia (PSA). Herein PSA has been reviewed concerning novel studies in the frame of reference to epidemiological facts, advances in treatment and prognostic factors. Speech and language therapy (SLT) are the backbone of the management of aphasia. Likewise, in the acute context, reperfusion therapy has recently emerged as an influential option for better progression. In combination with SLT, pharmacotherapy specifically Donepezil and Memantine appear to work better though further research is warranted on its effectiveness on global language function. Testimonial of the usefulness of non-invasive brain stimulation techniques for PSA is preliminary but assuring and transcranial direct current stimulation trials are encouraging. A rarely discussed treatment option, acupuncture has been evidenced to result in impressing outcomes for motor PSA, functional communication, and linguistic abilities. Moreover, SPEAK-6 and aNIHSS tools have been recently developed and proved to predict prognosis at 6 months and 24 hours, respectively. Studies revealed several prognostic factors for PSA including the age at onset, location of the lesion, infarct size, baseline language ability, education level of the patient, white matter preservation and mechanism of neuroplasticity. Therefore, further research for treatment and prognosis of PSA are indicated with many participants, including varieties of aphasia types, explaining the pathophysiology of these recoveries of the novel approaches and details on the optimal daily dosage, intensity, and duration of these therapies.
Factors influencing the e-learning effectiveness and its reflection on learning quality: The role of hospitality students' perception

This study examines the effect of five factors namely; administrative support, course design, instructor characteristics, learner characteristics, and technical support on the effectiveness of Elearning among students enrolled in hospitality management programs. In addition, investigates the relationship between the effectiveness of E-learning and its quality taking into consideration the role of students’ perception. 250 responses gathered from undergraduate students enrolled in the University of Sadat City in Egypt were analyzed using PLS-SEM. Contrary to the expectations of the study model, the results showed an insignificant relationship between instructor characteristics and E-learning effectiveness. On the other hand, the results showed a positive relationship between the other four factors and E-learning effectiveness. Moreover, Elearning effectiveness showed a positive relationship with students’ perceptions of E-learning, in addition, students’ perceptions of E-learning showed a positive relationship with the quality of Elearning. The research provides a theoretical contribution to bridging the gap in studies related to E-learning in hospitality higher education. Practically, the research provides hospitality higher education institutions with recommendations to understand the barriers to E-learning. Limitations and potential directions for future research were also presented.
Kinetic simulations of 3‐D Farley‐Buneman turbulence and anomalous electron heating

Electric fields map from the magnetosphere to the E region ionosphere where they drive the intense currents of the auroral electrojet. Particularly during geomagnetic storms and substorms, these currents become sufficiently intense to develop Farley‐Buneman (FB) streaming instabilities and become turbulent. This leads to anomalous electron heating which can raise the electron temperature from 300 K to as much as 4000 K and, also, modifies auroral conductivities. This paper describes the first fully kinetic 3‐D simulations of electric field‐driven turbulence in the electrojet and compares the results with 2‐D simulations and observations. These simulations show that 3‐D turbulence can dramatically elevate electron temperatures, enough to explain the observed heating. They also show the saturated amplitude of the waves; coupling between linearly growing modes and damped modes; the propagation of the dominant modes at phase velocities near the acoustic velocity, slower than in 2‐D simulations; and anomalous cross‐field electron transport, leading to a greatly increased E region Pedersen conductivity. These simulations provide information useful in accurately modeling FB turbulence and represent significant progress in understanding the electrojet.
Does CSR lead to the enhancement of employees’ work engagement?

: Corporate Social Responsibility (CSR) has been attracting the attention of academics and practitioners in recent years. Nonetheless, there is a deficiency of researches on how CSR influences employees’ affirmative behavior toward their corporations. By considering the dearth of engaged employees in organizations around the world, it could be expected that CSR initiatives used by corporations one of the key drivers of enhancing Employee work engagement. This current study scrutinizes the roles of CSR in developing a sense of Pride in Membership, Well-being and Work Engagement among the employees. A theoretical research model was investigated via structural equation modeling (SEM) using 338 survey responses. The respondents’ work in different national & multi-national organizations in Bangladesh that is actively engaged in CSR. The results indicate that Employee Well-being is an important mediator of the relationship between CSR and Work engagement. However, the mediating role of PIM on CSR and Work engagement did not fulfill our expectations. Though, this study contributes to CSR and Work engagement literature and will provide useful policy implications to the managers to involve employees in Corporate Social Responsibility activities in order to increase their work engagement level.
The complex universe: recent observations and theoretical challenges

The large-scale distribution of galaxies in the universe displays a complex pattern of clusters, super-clusters, filaments and voids with sizes limited only by the boundaries of the available samples. A quantitative statistical characterization of these structures shows that galaxy distribution is inhomogeneous in these samples, being characterized by large amplitude fluctuations of large spatial extension. Over a large range of scales, both the average conditional density and its variance show a non-trivial scaling behavior: at small scales, r < 20 Mpc/h, the average (conditional) density scales as r − 1. At larger scales, the density depends only weakly (logarithmically) on the system size and density fluctuations follow the Gumbel distribution of extreme value statistics. These complex behaviors are different from what is expected in a homogeneous distribution with Gaussian fluctuations. The observed density inhomogeneities pose a fundamental challenge to the standard picture of cosmology but they also represent an important opportunity which points to new directions with respect to many cosmological puzzles. Indeed, the fact that matter distribution is not uniform, in the limited range of scales sampled by observations, raises the question of understanding how inhomogeneities affect the large-scale dynamics of the universe. We discuss several attempts which try to model inhomogeneities in cosmology, considering their effects with respect to the role and abundance of dark energy and dark matter.
Local angular fractal and galaxy distribution

The power-law dependence of the angle in the angular projection of galaxy distribution is explained by assuming that in the spherical shells within a small angle the distributions are also fractal. If this local angular fractal is possessed, a fractal structure is angularly-isotropic at each occupied point though inhomogeneous, and is compatible with the present evidence claimed to be of homogeneity for galaxy distribution. Further, it is most likely to be isotropic rather than only angularly-isotropic. Several related issues are discussed.
Adaptive Beam Search in Sequence-to-Sequence Models

Natural language processing tasks usually require to decode the most likely output sequence which involves searching through all the possible output sequences based on their likelihood. Beam search is a heuristic search algorithm used in the test-time decoding of sequence-to-sequence model. While it might have an advantage over greedy search for accuracy, it leads to time and resource hunger due to keeping and searching through a ﬁxed amount of beams at each step as the beam size increases. We aim to address this problem and propose methods of adapting the beam size for decoding with help of deterministic agent and reinforcement learning, in particular for the decoding phase in Seq2Seq model. In the experiments we show that the proposed adaptive beam search strategies yield better results on two NLP tasks compared with baseline models.