Miracle-dz/UniFAR-FTUs huggingface dataset:
Generation of microwave fields in cavities with laser-excited nonlinear media: competition between the second- and third-order optical nonlinearities

We discuss a scheme for the parametric amplification of the quantum fluctuations of the electromagnetic vacuum in a three-dimensional microwave resonator, and report the preliminary measurements to test its feasibility. In the present experimental scheme, the fundamental mode of a microwave cavity is nonadiabatically perturbed by modulating the index of refraction of the nonlinear optical crystal enclosed therein. Intense, multi-GHz laser pulses, such as those delivered by a mode-locked laser source, impinge on the crystal to accomplish the n-index modulation. We theoretically analyze the process of parametric generation, which is related to the third-order nonlinear coefficient χ(3) of the nonlinear crystal, and assess the suitable experimental conditions for generating real photons from the vacuum. Second-order nonlinear processes are first analyzed as a possible source of spurious photons in quantum vacuum experiments when an ideal, mode-locked laser source is considered. The combination of a crystal non-null χ(2) coefficient and a real mode-locked laser system—i.e. one featuring offset-from-carrier noise and unwanted secondary oscillations—is also experimentally investigated, paving the way for future experiments in three-dimensional cavities.
Studies of AM He Atomic Magnetometer for Fusion Plasmas

Amplitude modulated helium atomic magnetometers (AM He AOM) are proposed as a new method, which allows spatially resolved magnetic field measurement in the inner regions of burning plasmas without heating beams nor impurity atoms. In order to understand the fundamental properties of AM He AOM, we have developed a prototype, and Helium discharge lamp as well as its power supply has been also elaborated as a light source. 1083 nm AM emission was successfully obtained in the frequency range between 40 kHz and 500 kHz. We have performed an exploratory experiment of test magnetic field measurement with the developed AM He AOM. For the test magnetic fields: 2.6 μT and 5.0 μT, possible signs of magnetic field have been observed.
Object-Color Description Under Varying Illumination

Given a fixed and uniform illumination, metameric objects appear as the same color. However, when the illumination is altered, two metameric reflecting objects under the first illuminant may no longer produce the same color signal under the second. This situation is called metamer mismatching. Metamer mismatching poses several challenges for the camera and display industries as well as color-based computer vision technology. In light of metamer mismatching, the present study criticizes the conventional approaches to color description when the illuminant alters, and then lays a foundation to robustly describe object colors under varying illumination conditions. Later, the degree of metamer mismatching is used as a measure of the quality of lights. We demonstrate that although the common color spaces such as CIELAB and related spaces in the literature may work well for a fixed illuminant, they can lead to poor results when the illuminant is changed. In view of these problems, new descriptors for hue, lightness and chroma are presented that are based on properties of a Gaussian-like spectrum metameric to the given color tristimulus coordinates. Experiments show that the new Gaussian-based appearance descriptors correlate with different descriptors as well as the CIECAM02 appearance model does on average. Furthermore, the Gaussian-based descriptors are significantly more stable than the descriptors defined in the CIECAM02 appearance model. Afterwards, the problem of predicting how the color signal arising in response to light reflected from the surface of an object is likely to change when the lighting alters is investigated. A new method, called the Gaussian Metamer (GM) method is proposed for predicting what a color signal observed from a surface under a first light is likely to be when the same surface is lit instead by a second light. Due to metamer mismatching, there is not a unique answer for this problem. Our approach is to use one of the possible metamers that is likely to do well on average. The results outperform other state-of-the-art prediction methods.
Enhancement of spectral quality of archival aerial photographs using satellite imagery for detection of land cover

Abstract. Archival aerial photographs are often the only reliable source of information about the area. However, these data are single-band data that do not allow unambiguous detection of particular forms of land cover. Thus, the authors of this article seek to develop a method of coloring panchromatic aerial photographs, which enable increasing the spectral information of such images. The study used data integration algorithms based on pansharpening, implemented in commonly used remote sensing programs: ERDAS, ENVI, and PCI. Aerial photos and Landsat multispectral data recorded in 1987 and 2016 were chosen. This study proposes the use of modified intensity-hue-saturation and Brovey methods. The use of these methods enabled the addition of red-green-blue (RGB) components to monochrome images, thus enhancing their interpretability and spectral quality. The limitations of the proposed method relate to the availability of RGB satellite imagery, the accuracy of mutual orientation of the aerial and the satellite data, and the imperfection of archival aerial photographs. Therefore, it should be expected that the results of coloring will not be perfect compared to the results of the fusion of recent data with a similar ground sampling resolution, but still, they will allow a more accurate and efficient classification of land cover registered on archival aerial photographs.
Development of measurement protocols for quantum magnetometry

The work presented in this thesis revolves around quantum enhanced magnetic field sensing. The core of the study is the nitrogen-vacancy (NV) center, a point defect in the diamond lattice with atomic like properties and magnetic field susceptibility. The central task was to develop control schemes and protocols to enhance the lifetime and the coherences of the NV center with the overall goal of enhancing the capabilities of this sensor in the field of magnetometry. In order to realize complex protocols, a sophisticated software control of the measurement setup is required. A general software framework, termed Qudi, was designed and developed from scratch to improve drastically the measurement abilities and to facilitate the transfer of knowledge between the measurement protocols and the underlying physical idea. The transparent character of the core code, fully open to the scientific community, is serving as rigorous framework to reduce the complexity of the setup configuration by a fundamental separation of tasks. As a consequence, the general idea of this framework is not limited to experiments with color centers in diamond, but can find application in any laboratory environment. The measurement of magnetic fields in the high-frequency GHz regimes is challenging. In this thesis, a continuous dynamical decoupling protocol is developed and implemented, which extends the capabilities of the NV sensor to probe GHz signals with a narrow bandwidth. Moreover, the protocol protects the system from noise, attributed to the drive, and from external magnetic noise thereby prolonging the coherence time and reaching the lifetime limitation of the quantum states. We measured a coherence time of 1.43ms at room temperature in a diamond crystal with a natural abundance of 13C atoms, resulting in a smallest detectable magnetic field strength of 4 nT at 1.6GHz. Creating a protected qubit from a three-level system requires multiple drive fields addressing different transition frequencies. Continuous dynamical decoupling can protect the system from external magnetic noise, but typically introduces large drive noise to the system. The combination of on-resonant and off-resonant driving fields serves an approach to circumvent the challenges associated with drive noise. While on-resonant drive maintains a large energy gap in order to protect the sensor from external magnetic noise, the off-resonant drive creates AC-Stark shifted energy levels, thereby significantly reducing the amount of drive noise on the three-level system. We experimentally demonstrate an improvement in coherence time, which is only limited by the second order contributions of the magnetic field noise while suppressing entirely the drive noise contributions. Further improvement can be achieved by a mere increase of the drive field as its noise is efficiently decoupled from the sensor.
Screening and optimization of extracellular pectinase produced by Bacillus thuringiensis SH7

Abstract The objective of the current research was to identify and evaluate the possibility of production of pectinase, also known as pectin degrading enzymes, from indigenous bacterial strains. Qualitative screening of isolated bacterial strains showed that among 29 bacterial strains, 5 have maximum enzymatic activity. The highest pectinase producing strains were quantitatively analyzed for enzyme production. SH7 strain was found as highest pectinase producer (0.77 IU/mL) that was further analyzed to molecular level by amplification of 16s rRNA. It was found 100% similar with other reported strains of Bacillus thuringiensis. Medium optimization was performed to optimize fermentation conditions for maximum enzyme yield. An experimental design containing 12 experimental runs was designed by Plackett–Burman design (PBD). Maximum pectinase activity was obtained at 45°C after 24 h when the growth medium was supplemented with 2.5% nitrogen, 5.0% substrate, MgSO4 as metal ion, 1% inoculum size, and pH was adjusted to 6. Factorial regression analysis of the PBD design was performed and the overall design was also found significant in terms of R square value. In PBD, the most significant factors for production were temperature, pH, metal ion concentration, and nitrogen source. Central composite design (CCD) design consisting of 26 experimental runs was employed to optimize these four significant factors. The overall model summary showed maximum pectinase activity (19.2 IU/mL) at 37°C temperature, 0.08 NaCl, 1.7% nitrogen source, and pH 8.4. In CCD, NaCl, nitrogen source, and pH were also reported as significant factors by the Pareto chart, probability plots, and 3D interactions.
A study of fuzzy anti-λ-ideal convergent triple sequence spaces

Abstract A class with ambiguous status of its elements by a membership function that assigns to each element a grade in the close interval [ 0 , 1 ] {[0,1]} ; Lofti Zadeh introduced this idea into theory as fuzzy sets in the year of 1965. A study of fuzzy anti-normed linear spaces by Kočinac on some topological properties motivated us to work on fuzzy anti-normed triple sequence spaces with respect to ideal by using compact linear operator. Further, we prove some theorems, particularly on convergence and completeness.
Hindsight2020: Characterizing Uncertainty in the COVID-19 Scientific Literature

Abstract Following emerging, re-emerging, and endemic pathogen outbreaks, the rush to publish and the risk of data misrepresentation, misinterpretation, and even misinformation puts an even greater onus on methodological rigor, which includes revisiting initial assumptions as new evidence becomes available. This study sought to understand how and when early evidence emerges and evolves when addressing different types of recurring pathogen-related questions. By applying claim-matching by means of deep learning Natural Language Processing (NLP) of coronavirus disease 2019 (COVID-19) scientific literature against a set of expert-curated evidence, patterns in timing across different COVID-19 questions-and-answers were identified, to build a framework for characterizing uncertainty in emerging infectious disease (EID) research over time. COVID-19 was chosen as a use case for this framework given the large and accessible datasets curated for scientists during the beginning of the pandemic. Timing patterns in reliably answering broad COVID-19 questions often do not align with general publication patterns, but early expert-curated evidence was generally stable. Because instability in answers often occurred within the first 2 to 6 mo for specific COVID-19 topics, public health officials could apply more conservative policies at the start of future pandemics, to be revised as evidence stabilizes.
Evolution of the ISM in main-sequence versus starburst galaxies: A motivation for molecular deep fields

Abstract In the last decade, significant progress has been made to understand the evolution with redshift of star formation processes in galaxies. Its is now clear that the majority of galaxies at z<3 form a nearly linear correlation between their stellar mass and star formation rates and appear to create most of their stars in timescales of ~1 Gyr. At the highest luminosities, a significant fraction of galaxies deviate from this main-sequence, showing short duty cycles and thus producing most of their stars in a single burst of star formation within ~100 Myr, being likely driven by major merger activity. Despite the large luminosities of starbursts, main-sequence galaxies appear to dominate the star formation density of the Universe at its peak. While progress has been impressive, a number of questions are still unanswered. In this paper, I briefly review our current observational understanding of this main-sequence vs starburst galaxy paradigm, and address how future observations will help us to have better insights into the fundamental properties of the interstellar medium of these galaxies. Finally, I show recent attempts to conduct molecular deep field observations and the motivation to perform molecular deep field spectroscopy with the Atacama Large Millimeter/submillimeter Array.
Performance enhancement of graphene plasmonic nanoantennas for THz communication

The concept and analysis of a graphene plasmonic nanoantenna over a SiO 2 /Si substrate at terahertz (THz) band are presented. The performance enhancement of the antenna is proposed by dynamically controlling the surface conductivity of graphene using an electric field effect. The controlling ability of graphene via gate voltage enables frequency reconfiguration of the antenna over a wide range of 2.56-4.98 THz. The performance merits of the antenna are its high directivity, broadside radiation pattern, low reflection coefficient, stable impedance and high miniaturisation. The proposed graphene plasmonic antenna has potential to be used for THz communication.
Mode-free electromagnetic bandgap materials with broadside radiation as phased array antenna elements

Abstract This paper presents a new class of electromagnetic bandgap material (EBG), which we define as the bandgap-antenna structure. It is a true EBG material, with both surface and leaky waves suppressed from the whole structure along all lateral directions, and it is also an antenna element simultaneously. The configuration has two metallization layers of sliced concentric rings between a square-shaped radiating top metal layer and a bottom ground plane. The lower rings are connected to the ground plane through vias and the patch of the top layer is fed with a probe. Eigenmode- and transmission-based full-wave modal analyses of the whole structure proved the presence of a mode-free bandgap region within which the proposed design radiates to broadside direction with 6.01 dBi gain. This structure is an ideal choice for phased array elements due to being modeless along the lateral directions while radiating to the broadside direction; phased array elements will be isolated if the proposed construction is used for array elements.
Numerical Haemodynamics in the Human Heart

Numerische patientenspezifische Herzmodelle sind weit davon entfernt im klinischen Alltag angewandt zu werden. Die Erzeugung ist aufwendig und die Nachbearbeitung ist nicht standardisiert. Es wird angenommen, dass die charakteristische Wirbelbildung im Herzen bereits in fr\"uhen Krankheitsstadien beeinflusst wird. Stromungsgrosen zu identifizieren, die in Zusammenhang mit dem Gesundheitszustand des Patienten stehen, ist wichtig. Wissenschaftler verfolgen daher als langfristiges Ziel die Entwicklung einfacher Modelle, die schnell gelost werden konnen und dennoch wertvolle Informationen liefern. Hierzu liefert diese Arbeit einen Beitrag. Zunachst muss die Verarbeitung der Daten standardisiert werden, um zuverlassige Masstabe in Forschung und Klinik zu generieren. In der vorliegenden Arbeit liegt der Fokus auf der Wirbelidentifikation. Eulersche und Lagrangesche Methoden liefern in Kombination viele Informationen, beispielsweise uber Wirbelbildung und Aufenthaltszeiten von Partikeln. Die gewahlten Methoden werden im Hinblick auf ihre raumlichen und zeitlichen Auflosungen charakterisiert. Es werden objektive Kriterien entwickelt, die eine automatisierte Verarbeitung der Stromungsdaten ermoglichen. Anschliesend mussen Vereinfachungen der in-silico Modelle identifiziert werden. Ziel ist es, die beste Kosten-Nutzen Variante zu finden. Im Fokus liegt die Mitralklappe, da sie die Einstromung in den linken Ventrikel steuert. Allerdings ist die Simulation der komplexen Bewegung schwierig und rechenintensiv. Obwohl verschiedene Modelle existieren, wurden sie selten direkt miteinander verglichen. Die vorliegende Arbeit schliest eine Lucke, indem ein vereinfachtes ebenes Klappenmodell mit einer dreidimensionalen Klappe innerhalb eines vereinfachten Ventrikels verglichen wird.
Enhanced x-rays from resonant betatron oscillations in laser wakefield with external wigglers

Generation of ultra-short betatron x-rays by laser-accelerated electron beams is of great research interest as it has many applications. In this paper, we propose a scheme for obtaining bright betatron x-rays by applying external wiggler magnetic field in the laser wakefield to resonantly drive the betatron oscillations of the accelerated electrons therein. This results in a significant enhancement of the betatron oscillation amplitude and generation of bright x-rays with high photon energy. The scheme is demonstrated using two-dimensional particle-in-cell simulation and discussed using a simple analytical model.
Connecting the dots: Harnessing dual-site transcranial magnetic stimulation to assess the causal influence of medial frontal areas on the motor cortex

Dual-site transcranial magnetic stimulation (TMS) has been widely employed to investigate the influence of cortical structures on the primary motor cortex (M1). Here, we leveraged this technique to probe the causal influence of two key areas of the medial frontal cortex, namely the supplementary motor area (SMA) and the medial orbitofrontal cortex (mOFC), on M1. We show that SMA stimulation facilitates M1 activity across short (6 and 8 ms) and long (12 ms) inter-stimulation intervals, putatively recruiting cortico-cortical and cortico-subcortico-cortical circuits, respectively. Crucially, magnetic resonance imaging revealed that this facilitatory effect depended on a key morphometric feature of SMA: individuals with larger SMA volumes exhibited more facilitation from SMA to M1. Notably, we also provide evidence that the facilitatory effect of SMA stimulation at short intervals did not arise from spinal interactions of volleys descending simultaneously from SMA and M1. On the other hand, mOFC stimulation moderately suppressed M1 activity at both short and long intervals, irrespective of mOFC volume. These results suggest that dual-site TMS is an interesting tool to study the differential influence of SMA and mOFC on M1 activity, paving the way for the multi-modal assessment of these fronto-motor circuits in health and disease. Key points Dual-site TMS has been widely employed to investigate effective connectivity between cortical structures and the primary motor cortex (M1). Here, we probed the causal influence of the supplementary motor area (SMA) and the medial orbitofrontal cortex (mOFC) on M1 activity. SMA stimulation facilitates M1 activity at both short and long inter-stimulation intervals; this facilitatory effect is related to SMA volume. mOFC stimulation moderately suppresses M1 activity, independent of mOFC volume. The findings pave the way for multi-modal assessment of fronto-motor circuits in health and disease.
Track reconstruction for the Mu3e experiment based on a novel Multiple Scattering fit

The Mu3e experiment is designed to search for the lepton flavor violating decay μ + → e + e + e − . The aim of the experiment is to reach a branching ratio sensitivity of 10−16 . In a first phase the experiment will be performed at an existing beam line at the Paul-Scherrer Institute (Switzerland) providing 108 muons per second, which will allow to reach a sensitivity of 2 · 10−15 . The muons with a momentum of about 28 MeV/c are stopped and decay at rest on a target. The decay products (positrons and electrons) with energies below 53MeV are measured by a tracking detector consisting of two double layers of 50 μm thin silicon pixel sensors. The high granularity of the pixel detector with a pixel size of 80 μm × 80 μm allows for a precise track reconstruction in the high multiplicity environment of the Mu3e experiment, reaching 100 tracks per reconstruction frame of 50 ns in the final phase of the experiment. To deal with such high rates and combinatorics, the Mu3e track reconstruction uses a novel fit algorithm that in the simplest case takes into account only the multiple scattering, which allows for a fast online tracking on a GPU based filter farm. An implementation of the 3-dimensional multiple scattering fit based on hit triplets is described. The extension of the fit that takes into account energy losses and pixel size is used for offline track reconstruction. The algorithm and performance of the offline track reconstruction based on a full Geant4 simulation of the Mu3e detector are presented.
Identifying intraclass correlations necessitating hierarchical modeling

ABSTRACT Hierarchical binary outcome data with three levels, such as disease remission for patients nested within physicians, nested within clinics are frequently encountered in practice. One important aspect in such data is the correlation that occurs at each level of the data. In parametric modeling, accounting for these correlations increases the complexity. These models may also yield results that lead to the same conclusions as simpler models. We developed a measure of intraclass correlation at each stage of a three-level nested structure and identified guidelines for determining when the dependencies in hierarchical models need to be taken into account. These guidelines are supported by simulations of hierarchical data sets, as well as the analysis of AIDS knowledge in Bangladesh from the 2011 Demographic Health Survey. We also provide a simple rule of thumb to assist researchers faced with the challenge of choosing an appropriately complex model when analyzing hierarchical binary data.