Miracle-dz/UniFAR-FTUs huggingface dataset:
Mixed state dynamical quantum phase transitions

Preparing an integrable system in a mixed state described by a thermal density matrix , we subject it to a sudden quench and explore the subsequent unitary dynamics. Defining a version of the generalised Loschmidt overlap amplitude (GLOA) through the purifications of the time evolved density matrix, we claim that non-analyiticies in the corresponding "dynamical free energy density" persist and is referred to as mixed state dynamical quantum phase transitions (MSDQPTs). Furthermore, these MSDQPTs are uniquely characterised by a topological index constructed by the application of the Pancharatnam geometry on the purifications of the thermal density matrix; the quantization of this index however persists up to a critical temperature. These claims are corroborated analysing the non-equilibrium dynamics of a transverse Ising chain initially prepared in a thermal state and subjected to a sudden quench of the transverse field.
The Origins of Gravitational Fields

This paper asks and addresses several questions. First, why don’t gravitational theories include near field gravity probes and gravity modification as part of the bigger picture? And therefore, the next question is, is the gravitational constant G a constant or a variable? Based on a study of 798 isotopes, this investigation shows that G is a variable and a function of the mass of the nuclei. Second, by showing that much of theoretical physics is cantered on the field structure, not the source, the paper asks the question, is mass the source of gravitational fields or is it a proxy for some other property of matter? By making some extrapolations of quark masses, the paper shows how quark motion, not quark mass, is the source of gravitational fields. Higgs field implicitly assumes that mass is a property that is external or extrinsic to the property of the particle. Finally, by asking the question is it possible to derive a description of mass that is intrinsic to the particle, and to its existing properties? Is it possible to derive a property of mass without adding anything new? By deriving a different mass model from Higgs Field, a particle structure that is consistent with both mass-based and massless particles is derived. This mass model suggests that the law of conservation of mass is not as fundamental as we thought it is. That particle radius plays an important part in this conservation law and could lead to the answer of the proton radius puzzle.
The evanescent wave coronagraph project: setup results and demonstrator preliminary design

The objective of the Evanescent Wave Coronagraph (EvWaCo) project is to develop a new kind of simple and cost effective coronagraph, first for ground-based telescopes and then for space-based telescopes. The principle involves the tunneling effect to separate the star light from the companion light. The star light is directed transmitted toward a WaveFront Sensor (WFS) that measures the wavefront distortions in the immediate proximity of the occulting mask with minimum non-common path errors. The beam reflected by the mask propagates toward the Lyot stop and forms the images of the companion and of the star residuals on the camera. The EvWaCo concept has been demonstrated and this instrument is achromatic over the I-band of the Johnson- Cousins photometric system in unpolarized light. We have measured over this photometric band an Inner Working Angle (IWA) equal to 6 λ/D and contrasts of a few 10-6 at distances greater than 10 Airy radii from the star Point Spread Function (PSF) center. This paper describes the continuation of the project, from this setup of demonstration to the first prototype operating on the sky at horizon 2020. The objective is to show the capability of the full system to provide IWA and raw contrasts close to the state-of-art performance with the Thai National Telescope, by observing through an unobstructed elliptical pupil of major axis length equal to 1 m. The system will demonstrate over the full I-band an IWA close to 3 λ/D and raw contrasts equal to a few 10-4 at a distance equal to the IWA from the PSF.
Multivariate Factorisable Sparse Asymmetric Least Squares Regression

More and more data are observed in form of curves. Numerous applications in finance, neuroeconomics, demographics and also weather and climate analysis make it necessary to extract common patterns and prompt joint modelling of individual curve variation. Focus of such joint variation analysis has been on fluctuations around a mean curve, a statistical task that can be solved via functional PCA. In a variety of questions concerning the above applications one is more interested in the tail asking therefore for tail event curves (TEC) studies. With increasing dimension of curves and complexity of the covariates though one faces numerical problems and has to look into sparsity related issues. Here the idea of FActorisable Sparse Tail Event Curves (FASTEC) via multivariate asymmetric least squares regression (expectile regression) in a high-dimensional framework is proposed. Expectile regression captures the tail moments globally and the smooth loss function improves the convergence rate in the iterative estimation algorithm compared with quantile regression. The necessary penalization is done via the nuclear norm. Finite sample oracle properties of the estimator associated with asymmetric squared error loss and nuclear norm regularizer are studied formally in this paper. As an empirical illustration, the FASTEC technique is applied on fMRI data to see if individual’s risk perception can be recovered by brain activities. Results show that factor loadings over different tail levels can be employed to predict individual’s risk attitudes.
Trends and factors associated with neonatal mortality among Neonates hospitalized at the Women and Newborn Hospital in Lusaka Zambia in the pre-covid 19 period

Background Neonatal mortality is a global problem especially in resource-poor settings such as sub-Saharan African Countries. Trends and factors associated with neonatal mortality vary in different settings. This cross-sectional study investigated trends and factors that are associated with increased neonatal mortality among hospitalised neonates with a view of identifying pointers that can be modified to help improve neonatal survival. Methods Medical records for all neonates admitted to the NICU in 2018 and 2019 were reviewed for the study. The Mortality rates were calculated using WHO standard and Microsoft excel 2010 used to construct monthly trends analysis using monthly totals. Univariate and multivariate logistic regression analysis to determine the factors associated with neonatal deaths at the tertiary facility using Stata version 14.2. Model fit was evaluated using Hosmer and Lemeshow test (chi2=13.90, P =0.0845), implies the models estimates fit the data at an acceptable level. Results A total of 7,581 admissions were seen and 2340 files were extracted for analysis, of which 940 (40.2%) died. The overall Neonatal mortality percentage during the study period was 31.8%. Relatively similar trends were observed during the study period with differences in case fatality rates. Factors associated with an increased odds of dying were not attending antenatal care (AOR=2.09, 95% CI [1.46 - 2.99] p <0.0001), parity (AOR=1.09, 95% CI [1.02 - 1.16] p=0.0013) and age of the neonate in days (AOR=0.92, 95% CI [0.91- 0.94] p <0.0001). Conclusion Neonatal mortality is high among hospitalized neonates at the Women and New-born Hospital in Zambia. Associated Factors included no antenatal attendance, increased parity, and early age of the neonate. This has detrimental effects; hence emphasis is on early Antenatal Care for easy monitoring of mother and neonates for fast actions in case of complications Keywords: Neonate, neonatal mortality, trends, risk factor
A level-set method for ultrasound-driven bubble motion with a phase change

ABSTRACT A level-set (LS) method is presented for computation of ultrasound-driven bubble motion including the effect of liquid and vapor compressibility as well as the effect of liquid–vapor phase change. The semi-implicit pressure correction formulation is implemented into the LS method to avoid the serous time-step restriction in low Mach number (or near incompressible) flows. The numerical results for one-dimensional compressible flows and spherical bubble motion in a periodic acoustic field show good agreement with the analytical solutions. The effects of phase change and ambient temperature on the ultrasound-driven bubble motion are quantified.
Implicit treatment of model error using inflated observation‐error covariance

Data assimilation involving imperfect dynamical models is an important topic in meteorology, oceanography and other geophysical applications. In filtering methods, the model error is compensated for by inflation. In variational data assimilation, authors usually try to estimate it, which means that all uncertainty‐loaded model inputs are included into the control vector. However, this approach suffers from implementation difficulties. In this paper we suggest an alternative method, motivated by the ‘nuisance parameter’ concept known in statistics. This method allows the model error to be treated implicitly by inflating the observation‐error covariance. The equivalency theorem substantiating the method has here been proved. We also consider a case with a biased model error. In the corresponding mixed formulation, the spatially distributed mean error is included into the control vector, whereas the time‐dependent fluctuations around the mean are subjected to the proposed implicit treatment. Numerical experiments for the 1D generalized Burgers' equation illustrate the presented theory. In these experiments the model error related to uncertainty in the advection coefficient has been considered.
Antidepressant Profile of Bupropion and three Metabolites in Mice

Bupropion is a novel antidepressant, distinct from tricyclic antidepressants both neurochemically and behaviorally. Bupropion forms several metabolites in both rodents and humans. Three chemically different molecules BW 306, BW 494, and BW 287 were selected. Comparative assessment of antidepressant activity of bupropion and its metabolites in mice, and pharmacological analysis of possible mechanisms of action of the parent drug and its metabolites (using interaction studies with pimozide, D,L-propranolol, and prazosin) were carried out.
GPS Carrier-Phase Time Transfer Boundary Discontinuity Investigation | NIST

We report on a study of the carrier-phase time transfer boundary discontinuity by the use of the precise point positioning (PPP) technique. Carrier-phase time transfer is first compared with two-way satellite time and frequency transfer (TWSTFT) between the same stations. It matches TWSTFT quite well and provides better short-term stability. Later, we extract 1-day data-arc boundary discontinuity jump values for 151 days. The distribution of jump values is almost Gaussian. Different GPS receivers have different mean jump values (-200 ps to +200 ps) and different standard deviations (100 ps to 300 ps). Among the receivers at NIST (USA), USNO (USA), and PTB (Germany), USNO has the smallest absolute mean jump value (14.2 ps) and the smallest deviation (105.1 ps). In addition, with the increase of data-arc from 1-day to 4-days, both mean value and deviation increase. For receivers at the same station, the correlation varies. At PTB, the correlation between the jumps for receivers PTBB and PTBG is only -0.064. At NICT (Japan), the correlation between receivers SEPA and SEPB is 0.47, while that between receivers SEPB and SEPT is 0.10. The above variation in the correlation between receivers at the same location suggests that the boundary discontinuity does not mainly come from satellite-path-related noise. Further investigation reveals that multipath also contributes little to boundary discontinuity. Comparison between PPP and network method shows that the algorithm of fixing phase ambiguity plays an important role in boundary discontinuity.
Performance of a GEM detector with copper-less foils

In this paper we present results of systematic investigation of a GEM detector built of GEM foils and the drift electrode with mostly removed copper cladding, keeping in mind possible applications of such a detector to spectroscopic imaging of soft X-rays. Copper-less foils have been manufactured starting from the standard copper-clad foils and removing most of the copper but narrow strips forming 1 cm grid, and using adhesive chromium layer for detector bias distribution. Performance of the detector for various gas mixtures: Ar/CO2 (70/30), Xe/CO2 (90/10), Xe/TMA (95/5), and Kr/CO2 (80/20) has been evaluated. Spatial distributions of gas gain and energy resolution were measured over entire detector area of 10 × 10 cm with a pixel size of 800 × μm. During consecutive tests a significant variation of the mean value of the gas gain and increase of its spread across the detector was observed. The spatial variation of the gas gain formed mosaic patterns with square cells corresponding to the grid formed by copper strips on the drift electrode and on GEM foils. The energy resolution was not affected and stayed uniform across the detector area regardless variation of the gas gain. The observed deterioration of the detector is attributed to specific parameters of the GEM foils and specific processing steps and it is not considered as showstopper in further development of a copper-less GEM detector.
Imaging of Colonic Diverticular Disease

Diverticular disease affects approximately two thirds of the population over the age of 70. While only a small fraction of these patients will develop diverticulitis, adequate radiological evaluation of diverticulitis and its complications is imperative in determining proper medical and surgical treatment. Clinical examination and laboratory tests alone have been found to be inaccurate in deﬁning many aspects of the disease in up to 60% of cases. Over the past 30 years, contrast enema, computed tomography, and ultrasound have all been used extensively to diagnose the complications of diverticular disease. More recently, magnetic resonance imaging has been studied in patients with complicated diverticulitis. This article reviews the use of these different radiological modalities in diagnosing acute colonic diverticulitis and its complications.
Varieties over finite fields: quantitative theory

Algebraic varieties over finite fields are considered from the point of view of their invariants such as the number of points of a variety that are defined over the ground field and its extensions. The case of curves has been actively studied over the last thirty-five years, and hundreds of papers have been devoted to the subject. In dimension two or higher, the situation becomes much more difficult and has been little explored. This survey presents the main approaches to the problem and describes a major part of the known results in this direction. Bibliography: 102 titles.
Quasi-radial wall jets as a new concept in boundary layer flow control

ABSTRACT This work aims to introduce a novel concept of wall jets wherein the flow is radially injected into a medium through a sector of a cylinder, called quasi-radial (QR) wall jets. The results revealed that fluid dynamics of the QR wall jet flow differs from that of conventional wall jets. Indeed, lateral and normal propagations of a conventional three-dimensional wall jet are via shear stresses. While, lateral propagation of a QR wall jet is due to mean lateral component of the velocity field. Moreover, discharged Arrays of conventional three-dimensional wall jets in quiescent air lead to formation of a combined wall jet at large distant from the nozzles, while QR wall jet immediately spread in lateral direction, meet each other and merge together very quickly in a short distance downstream of the jet nozzles. Furthermore, in discharging the conventional jets into an external flow, there is no strong interaction between them as they are moving parallel. While, in QR wall jets the lateral components of the velocity field strongly interact with boundary layer of the external flow and create strong helical vortices acting as vortex generators.
Advance Study in the Generalized Circular Polarization and Scattering from Bi-Isotropic Objects

This paper discusses Different constitutive relations of generalized circular polarization in chiral media by using Maxwell’s equations. In a chiral medium for fields with generalized circular polarizations, the Maxwell equations and constitutive relations have the same form in the achiral medium, but the equivalent material parameters differ for field with different circular polarization. Thus a wave of circular polarization (left or right) propagates with the same wave number regardless of its direction of propagation. In this paper, electromagnetic scattering characteristics by general bi-isotropic objects are investigated based on the surface integral equations. By applying the surface equivalent principle, electromagnetic fields inside a homogeneous bi-isotropic region can be represented in terms of equivalent electric and magnetic currents distributed over its boundary surface.
Weil representations of , q > 3 odd, via presentation and compatibility of methods

ABSTRACT In this article, we construct Weil representations of quasi-split unitary groups (q>3) attached to quadratic extensions of finite fields, by using Bruhat-like presentations of those groups. More precisely, we define Weil representations of associating to each generator a linear map of a suitable ℂ-vector space satisfying the relations of the aforementioned presentation. In addition, we also address the natural question of the compatibility of our representation of with the classical one constructed by Gérardin.
High-Output Fistula

Despite improvements in healthcare delivery, mortality rates for high-output ﬁstulae remain unchanged. The pathophysiology and causes of ﬁstulae are reviewed in this article. An overview of the diagnostic procedures to delineate ﬁstulae and underlying bowel disease together with their complications is included. Management of high-output ﬁstulae consists of assessment and stabilization of patients, followed by conservative management by a multidisciplinary team until spontaneous or surgical closure of ﬁstulae.
Observations of temperature inversions over central Arctic sea ice in summer

We analysed high‐resolution tethersonde sounding data from the drifting ice station Tara in the Arctic Ocean in April to August 2007 to (i) better understand the multiple processes affecting the generation and properties of Arctic air temperature inversions and (ii) to obtain insight into the vertical structure of the atmospheric boundary layer during the exceptional spring and summer 2007, which resulted in a historically low sea ice extent. A total of 95 profiles, up to the height of 2 km, were measured on 39 days. Inversions were present in 88% of the data, 13% of them being surface‐based. Compared to winter, the occurrence and properties of summer inversions depended much less on surface net radiation and were mainly controlled by the surface melt and warm‐air advection. Inversions occurring during snow/ice melt were located at low altitudes, frequently based at the surface, and were often as strong as winter inversions reported in previous studies. In general, the Tara inversions were shallow, and the deepest ones were observed when clouds occurred inside or partly above the inversion layer. Inversions were strongest under clear skies or in cases when the cloud top was above the inversion base. Related to cases of strong warm‐air advection (up to 35 K day−1) in July, exceptionally high temperatures around the inversion top caused maximum inversion strengths up to 13 K. Inversions of this magnitude at this time of year have been rarely documented previously.
Energy dissipation in oxide glasses

The origin of sound attenuation at low and high frequency in glasses stays elusive mainly because of the complex temperature and frequency dependence of the phenomena at its root. Indeed, the presence of complex structures and multi-scale organizations in glasses induce the existence of relaxation time ranging from the second to the femto-second and of spatial correlation ranging from the Angstrom to a hundred nanometers. At low-frequency, a better understanding of the phenomena at the origin of dissipation would be beneficial to several applications. For example, the multi-layers coating the mirrors of gravitational waves detectors consists of a superposition of two oxide glasses: silicate (SiO2) and tantalum pentoxide (Ta2O5), are an important source of dissipation. At high frequency, the study of dissipation raises theoretical questions about the link between attenuation and dissipation as well as between loclt asymmetry and dissipation. In the present study, we conducted an analysis of the interaction between mechanical waves and the structure of two oxide glasses using simulation techniques such as non-equilibrium molecular dynamics. At high-frequencies, we implemented and used mechanical spectroscopy to measure dissipation numerically and performed in parallel an analytical development based on the projection of the atomic motion on the vibrational eigenmodes. At low-frequencies, we used molecular dynamics to gather sets of thermally activated events that we classed in three categories based on topologically distinct atomic motions and from which we predicted dissipation numerically using a refreshed TLS model
Quantum cascade lasers as metrological tools for space optics

A distributed-feedback quantum-cascade laser working in the 4.3÷4.4 mm range has been frequency stabilized to the Lamb-dip center of a CO2 ro-vibrational transition by means of first-derivative locking to the saturated absorption signal, and its absolute frequency counted with a kHz-level precision and an overall uncertainty of 75 kHz. This has been made possible by an optical link between the QCL and a near-IR Optical Frequency Comb Synthesizer, thanks to a non-linear sum-frequency generation process with a fiber-amplified Nd:YAG laser. The implementation of a new spectroscopic technique, known as polarization spectroscopy, provides an improved signal for the locking loop, and will lead to a narrower laser emission and a drastic improvement in the frequency stability, that in principle is limited only by the stability of the optical frequency comb synthesizer (few parts in 1013). These results confirm quantum cascade lasers as reliable sources not only for high-sensitivity, but also for highprecision measurements, ranking them as optimal laser sources for space applications.