Miracle-dz/UniFAR-FTUs huggingface dataset:
Development of a longer range standoff millimetre wave radar concealed threat detector

A millimeter wave (75 - 110 GHz) polarimetric radar system (MiRTLE) has been developed for the detection of threat objects, such as guns, knives, or explosive devices, which have been concealed under clothing upon the human body. The system uses a Gaussian lens antenna to enable operation at stand-off ranges up to 25 meters. By utilizing ultra-wideband Swept Frequency Continuous Wave Radar very high range resolution (~ 10mm) is realized. The system is capable of detecting objects positioned in front of the body and of measuring the range of a target. By interpretation of the scattered waveform, the presence of a wide spectrum of threat items concealed on the human body may be detected. Threat detection is autonomously rendered by application of a neural network to the scattered time domain, polarimetric radar returns and the system may be taught to alarm or reject certain classes of objects; this allows for highly specific or broad spectrum threat detection. The radar system is portable and operator steerable allowing standoff monitoring of moving human targets in real time. Rapid (1ms) sweep times and fast signal acquisition and processing allow decisions to be made at video frame rates (30 fps) and integrated directly to a video feed providing the operator with a field of view and facilitating aiming. Performance parameters for detection of guns and simulated explosive devices are presented for ranges up to 25 meters.
Crosstalk attenuation for imaging of multiples based on angle gather residual moveout analysis

Imaging of multiples, as a supplement to imaging of primaries, can provide a wider range of subsurface illumination. Therefore, it can provide more detailed information on subsurface structures. However, imaging of multiples suffers from crosstalk issues generated by unrelated events. Many strategies have been proposed to attenuate crosstalk, among which the angle domain Radon crosstalk attenuation algorithm achieves good application effect. In the angle domain, the true imaging is flat, while the crosstalk events have moveouts. Therefore, it is convenient to identify the crosstalk in angle gathers using the Radon transform. However, the conventional Radon transform lacks a quantitative description for crosstalk in angle gathers, which would affect the accuracy of crosstalk attenuation. In this paper, residual moveout kernels are derived with a Radon transform to attenuate crosstalk in angle gathers for imaging of multiples. First, two types of residual moveout (RMO) equations are derived based on the causality of crosstalk. A three-layer model is used to verify the correctness of the analytical solutions. Then, based on the derived equations, the two types of crosstalk can be attenuated respectively in the Radon domain. Synthetic experiments demonstrate that the derived RMO equations can effectively attenuate the crosstalk events in imaging of multiples.
Is Homocysteine Associated with the Prognosis of Covid-19 Pneumonia

Background/Aim. Coronavirus disease 2019 (COVID-19) is a life-threatening disease characterized by a prothrombotic state. Because homocysteine (Hcy) is a potential biomarker in thrombotic disease, this article aims to highlight the role of Hcy in the prognosis of COVID-19 pneumonia. Methods. This prospective study was conducted between April 2021 and December 2021 at the University of Health Sciences, Antalya Training and Research Hospital. 162 patients admitted to the emergency department for COVID-19 pneumonia and scheduled for hospitalization in the intensive care unit (ICU) or COVID-19 ward of the chest disease department were included in the study. Hcy levels and other necessary laboratory parameters were analyzed. Results. 134 patients were admitted to the COVID-19 ward and 28 to the ICU. Hcy levels were significantly higher in ICU patients than in ward patients (p : 0.001). Of the 134 patients, 55 later required ICU treatment for various reasons and were transferred to the ICU. Hcy (p : 0.010), ferritin (p : 0.041), and LDH (p : 0.010) were significantly higher in patients who were transferred to the ICU than in patients who remained in the ward. The Hcy level was associated with a poor prognosis. It was found that each unit increase in the Hcy level approximately doubled the risk of death in patients with COVID-19 (odds ratio: 1.753). Discussion. There are few studies examining the association between high Hcy levels and disease severity in COVID-19. Our study supports previous studies and shows the association between the need for intensive care and high Hcy levels. Conclusion. A high Hcy value is a helpful marker in determining the need for critical care on admission to the emergency department and a marker of poor prognosis in COVID-19 pneumonia.
I Choose You: Selecting Accurate Reference Genes for qPCR Expression Analysis in Reproductive Tissues in Arabidopsis thaliana

Quantitative real-time polymerase chain reaction (qPCR) is a widely used method to analyse the gene expression pattern in the reproductive tissues along with detecting gene levels in mutant backgrounds. This technique requires stable reference genes to normalise the expression level of target genes. Nonetheless, a considerable number of publications continue to present qPCR results normalised to a single reference gene and, to our knowledge, no comparative evaluation of multiple reference genes has been carried out in specific reproductive tissues of Arabidopsis thaliana. Herein, we assessed the expression stability levels of ten candidate reference genes (UBC9, ACT7, GAPC-2, RCE1, PP2AA3, TUA2, SAC52, YLS8, SAMDC and HIS3.3) in two conditional sets: one across flower development and the other using inflorescences from different genotypes. The stability analysis was performed using the RefFinder tool, which combines four statistical algorithms (geNorm, NormFinder, BestKeeper and the comparative ΔCt method). Our results showed that RCE1, SAC52 and TUA2 had the most stable expression in different flower developmental stages while YLS8, HIS3.3 and ACT7 were the top-ranking reference genes for normalisation in mutant studies. Furthermore, we validated our results by analysing the expression pattern of genes involved in reproduction and examining the expression of these genes in published mutant backgrounds. Overall, we provided a pool of appropriate reference genes for expression studies in reproductive tissues of A. thaliana, which will facilitate further gene expression studies in this context. More importantly, we presented a framework that will promote a consistent and accurate analysis of gene expression in any scientific field. Simultaneously, we highlighted the relevance of clearly defining and describing the experimental conditions associated with qPCR to improve scientific reproducibility.
Magneto-optic transitions and non-parabolicity parameters in the conduction band of semiconductors

The authors present a systematic formulation of the conduction band Hamiltonian in the presence of a magnetic field by an invariant expansion and by expressing the coefficients of this expansion in terms of the band parameters of an extended Kane model. This Hamiltonian can be used to describe non-parabolicity effects such as dipole-allowed spin-flip and higher-harmonic cyclotron resonance transitions and their angular dependence, and the magnetic-field dependence of the cyclotron mass and g-factor.
Diffusion, activation and recrystallization of boron implanted in preamorphized and crystalline germanium

We have investigated diffusion and activation of boron implanted with 6 keV energy to a maximum concentration of 8.0×1020atoms∕cm3 in crystalline germanium (c-germanium) and preamorphized germanium, employing rapid thermal annealing in the range of 400–600 °C. As-implanted boron profiles in preamorphized germanium are shallower than the ones in c-germanium due to channeling suppression. While boron diffusion is not observed either in c-germanium or during the germanium regrowth from amorphous state, the boron activation level achieved from the two starting phases is significantly different. A boron activation level of 2.4×1020atoms∕cm3 has been found in regrown germanium, while a level of only 1.2×1019atoms∕cm3 is observed in c-germanium. Remarkably, there is no evidence of any residual extended defectivity at the original crystalline/amorphous interface, when preamorphization is performed.
Fitting parametric frailty and mixture models under biased sampling

Biased sampling from an underlying distribution with p.d. f. f(t), t>0, implies that observations follow the weighted distribution with p.d. f. f w (t)=w(t)f(t)/E[w(T)] for a known weight function w. In particular, the function w(t)=t α has important applications, including length-biased sampling (α=1) and area-biased sampling (α=2). We first consider here the maximum likelihood estimation of the parameters of a distribution f(t) under biased sampling from a censored population in a proportional hazards frailty model where a baseline distribution (e.g. Weibull) is mixed with a continuous frailty distribution (e.g. Gamma). A right-censored observation contributes a term proportional to w(t)S(t) to the likelihood; this is not the same as S w (t), so the problem of fitting the model does not simply reduce to fitting the weighted distribution. We present results on the distribution of frailty in the weighted distribution and develop an EM algorithm for estimating the parameters of the model in the important Weibull–Gamma case. We also give results for the case where f(t) is a finite mixture distribution. Results are presented for uncensored data and for Type I right censoring. Simulation results are presented, and the methods are illustrated on a set of lifetime data.
The evolution of void-filled cosmological structures

1D, 2D, and 3D simulations are used here to investigate the salient features in the evolution of void-filled cosmological structures in universes with arbitrary values of Omega. It is found that the growth of a void as a function of time decreases significantly at the time corresponding to Omega = 0.5. In models constructed in 2D and 3D, suitable initial conditions lead to cellular structure with faceted voids similar to those observed in redshift surveys. Matter compressed to planes flows more rapidly toward condensations at the intersections than would be expected for spherical infall. The peculiar streaming velocities for void diameters of 5000 km/s should be observable. The simulations provide a more physical basis and dynamics for the bubbly and Voronois tesselation models used to derive statistical properties of cellular large-scale structure. 31 refs.
Probabilistic Inference of Comorbidities from Symptoms in Patients with Atrial Fibrillation: An Ontology-Driven Hybrid Clinical Decision Support System

Atrial fibrillation $(AF)$ is the most prevalent cardiac arrhythmia. While $AF$ is a cardiological disease, its risk factors and mechanisms are often rooted in non-cardiological comorbidities, introducing complexity in the treatment of the heterogeneous patient population. This study presents the development of a clinical decision support system (CDSS), which aims to mitigate potential challenges of the cross-disciplinarity of $AF$ A knowledge base is implemented to capture the hierarchical nature of relevant concepts. $Nai\dot{v}e$ Bayes classifiers are used to predict the patient comorbidities related to $AF$ mechanisms and risk factors based on provided symptoms. The resulting CDSS infers comorbidities with a top-k accuracy of 0.53, 0.80, and 0.88 for $k=1, 3$, and 5 respectively.
The Effect of Heart Rate and Atrial Contraction on Left Ventricular Function

Heart rate (HR) and effective atrial contraction affect left ventricular (LV) output. This is particularly relevant in atrial fibrillation (AF) patients, where HR is fast and irregular and atrial contraction almost completely absent. The effect of AF on the LV remains understudied, although a better understanding of these mechanisms could improve AF patient care. We have used a four-chamber electromechanics model to quantify how AF impacts LV function. Our model accounts for the effect of the pericardium and the coupling with the circulatory system, represented as a closed loop, providing physiological preload and afterload for the heart. The heart model was used for a factorial study with two HRs (70 bpm and 120 bpm) and in the presence and in the absence of atrial contraction. We found that an increased HR and lack of atrial contraction alone led to a small decrease in ejection fraction (42% to 40% and 42% to 41%, respectively). However, the interaction between an increased HR and lack of atrial contraction led to a drop in ejection fraction from 42% to 36%. This study demonstrates that our four-chamber heart models can be used to investigate the effect of rapid HR and ineffective atrial contraction on LV output and that AF can significantly impact LV function. This motivates further studies investigating the effect of AF on the whole heart.
Single frequency electrooptical tuning of an extended cavity diode laser at 1500 nm wavelength

A wavelength-tunable, single-frequency GaInAsP-InP laser diode using an intracavity electrooptic LiNbO/sub 3/ crystal as the wavelength selective component is discussed. Wavelength tuning is achieved by applying a driving voltage on the crystal electrodes. First results indicate a tuning rate of 1 GHz/V over a tuning range of about 4 nm. This performance was obtained using a nonoptimized X-cut, Z-propagating LiNbO/sub 3/ crystal. A potential tuning rate of 6.5 GHz/V is possible with reasonable improvements. >
The Algorithm for Preparing a Set of Data for Teaching Neural Networks on the Example of the Task to Analyze the Radiological Images of Lungs

The methodology for preparing data for teaching neural networks is considered in solving two problems: checking the modality of computed tomography and checking the modality of radiographic images. The algorithm for preparing data for neural networks training is proposed. The influence of the stages (marking of images, normalization of data, determining the dynamic image range, the composition of the training sample) of the algorithm for the learning result is evaluated. The greatest influence in solving the task of modality verification of modality was the choice of optimal values of the dynamic range. The change in the composition of the training sample made it possible to increase the accuracy of the classification by 0.0073. When solving the task of checking the modality of images of computed tomography, the most impact on the result of the training of the neural network had the stage of data normalization. The assumption is put forward that there are special signs of images of this modality.
The determination of the q-profile in the plasma core from Alfvén eigenmodes

The q-profile has been determined inside the q = 1 surface of ion cyclotron resonance frequency (ICRF) heated plasmas from the observed toroidicity induced Alfven eigenmodes (TAE) that appeared before giant sawtooth crashes. The q-profile deduced from the TAE spectrum is in good agreement with the one obtained from motional Stark effect measurements.
Low phase noise high power handling InGaAs photodiodes for precise timing applications

Time is the most precisely measured physical quantity. Such precision is achieved by optically probing hyperfine atomic transitions. These high Q-factor resonances demonstrate frequency instability of ~10-18 over 1 s observation time. Conversion of such a stable optical clock signal to an electrical clock through photodetection introduces additional phase noise, thereby resulting in a significant degradation in the frequency stability. This excess phase noise is primarily caused by the conversion of optical intensity noise into electrical phase noise by the phase non-linearity of the photodetector, characterized by its power-to-phase conversion factor. It is necessary to minimize this phase nonlinearity in order to develop the next generation of ultra-high precision electronic clocks. Reduction in excess phase noise must be achieved while ensuring a large output RF signal generated by the photodetector. The phase linearity in traditional system designs that employ a photoreceiver, namely a photodiode followed by a microwave amplifier, is limited by the phase non-linearity of the amplifier. Utilizing high-power handling photodiodes eliminates the need of microwave amplifiers. In this work, we present InGaAs p-i-n photodiodes that display a power-to-phase conversion factor <6 rad/W at a peak-to-peak RF output amplitude of 2 V. In comparison, the photodiode coupled to a transimpedance amplifier demonstrates >44 rad/W at a peak-to-peak RF output amplitude of 0.5 V. These results are supported by impulse response measurements at 1550 nm wavelength at 1 GHz repetition rate. These photodiodes are suitable of applications such as optical clock distribution networks, photonic analog-to-digital converters, and phased array radars.
Hearing Healthcare Professionals’ Views about Over-The-Counter (OTC) Hearing Aids: Analysis of Retrospective Survey Data

Over-the-counter hearing aids have been available to consumers in the US since 17 October 2022 following a ruling by the Food and Drug Administration. However, their reception by hearing healthcare professionals (HHP) has been mixed, and concerns have been expressed by many HHPs. The aim of this study was to examine the concerns that HHPs have towards over-the-counter (OTC) hearing aids. The study used a retrospective survey design. The survey data of HHPs (n = 730) was obtained from Hearing Tracker. A 22-item structured questionnaire was administered using a Question Scout platform. Descriptive analyses examined reported areas of concern and a Fisher’s exact test examined the relationship between demographics and responses. A cluster analysis with partitioning around medoids (PAM) was used to identify a sub-group of participants based on responses. Nearly half of HHPs who participated reported that they will support patients with OTC hearing aids purchased elsewhere, whereas a quarter reported that they will sell OTC hearing aids in their clinic or website. HHPs expressed over 70% agreement in ‘concern’ statements in 14 of the 17 items. Issues about safety, counseling, and audiological care were the key concerns expressed by HHPs about OTC hearing aids. Some demographics (i.e., profession, primary position) were associated with responses to some statements. Two groups were identified based on the responses to concern statements. The HHPs in the first cluster ‘OTC averse’ (51%) agreed on all the 17 concern statements, whereas the second cluster ‘OTC apprehensive’ (49%) had some items rated as disagree (i.e., consumers will give up on amplification) and neither agree nor disagree (i.e., do not provide good value, warranties and return periods will be worse), and remaining items were rated as agree. OTC hearing aids were initiated to improve affordability, accessibility, and hearing aid uptake and are currently a rapidly emerging category of hearing devices. Overall, the results of the current study indicate that HHPs have serious concerns about OTC hearing aids. HHP concerns cited in this study provide useful feedback to stakeholders (e.g., HHP professional agencies, FDA, industry, and insurance payers) involved in improving OTC hearing aid implementation.
A Search for Small-Scale Anisotropy in the Cosmic Microwave Background

We report the preliminary result of a search for cosmic microwave background (CMB) anisotropy. We made observations using a specially designed radiometer and on-axis Cassegrain telescope. The beam size was 12' at a frequency of 90 GHz. Observations were made during 1993 January from the South Pole. We observed five regions of sky near declination -75°, and set a 95% confidence level upper limit of ΔT< 2.3×10 -5 T CMB on Gaussian-correlated CMB anisotropy at an angular scale of O°. 15. This is the lowest upper limit to date on CMB anisotropy at this angular scale
Bistability in dark cloud chemistry

In this Letter we present the first report of a double steady state chemical solution in dark interstellar clouds. The discussion focuses on examples such as the degree of ionization and the C/CO ratio, but all the chemical abundances are concerned. The role of density and temperature is considered, and we explore the relevant range of these parameters where bistability occurs under interstellar conditions. The results are then discussed in terms of time evolution toward the two steady state solutions which are referred to as a low- and a high-ionization phase (LIP and HIP). We point out that the nonlinear interstellar chemical equations have the intrinsic property of bistability
K- and L-band spectroscopy of Be stars

Abstract We describe the behaviour of IR hydrogen emission lines of a sample of Be stars and discuss the physical properties of the circumstellar envelopes of Be stars classified in Groups I and II (Mennickent et al. 2009). We find that while Humphreys and Pfund lines of Group I stars form in an optically thick envelope/disk, Group II stars show Pfund lines that form in an optically thick medium and Humphreys lines originating in optically thinner regions. The transition between Groups I and II could be understood in terms of the evolution of the circumstellar disk of the star and might bring clues on the mechanism originating the Be phenomenon.
Low-loss single mode light waveguides in polymer

We report on the development of a UV-lithography manufacturing process for low loss single mode light waveguides in a novel polymer and the characterization of the fabricated components in a broad wavelength range from 808 nm to 1550 nm. The main focus of this work lies in providing a quick and cost efficient production technique for single mode waveguides and low loss integrated optical circuits. To achieve this goal we chose a novel photo-structurable polymer host-guest-system consisting of SU8 and a low refractive dopant monomer. Near and far-field measurements at different wavelengths show that the mode propagating within a well designed integrated waveguide structure and the mode of a standard fiber can exhibit a mode overlap value of approximately 1 and suffer only very low coupling losses. We demonstrate excess loss of 0.14 dB/cm for 808 nm, 0.33 dB/cm for 1310 nm and 2.86 dB/cm for 1550 nm. Typical insertion loss values of straight waveguides with a length of 36 mm are 0.9 dB for 808 nm, 1.5 dB for 1310 nm and 10.4 dB for 1550 nm. Polarization dependent loss was found to be less than 0.2 dB on sets of test structures of 36 mm length. We measured material attenuation in the novel polymer material before cross-linking of approximately 0.04 dB/cm for 808 nm and around 0.20 dB/cm for 1310 nm respectively. The presented production technique is suitable to provide low loss and low cost integrated optical circuits for sensor and communication applications in a broad wavelength range.