Miracle-dz/UniFAR-FTUs huggingface dataset:
Plasma processes in pulsar environments

The aim of this thesis is to study coherent plasma effects and collective plasma processes in pulsar environments. Pulsars are one of the most enigmatic objects in the universe. Formed in supernova explosions, pulsars are rapidly rotating neutron stars identified by their periodically pulsed electromagnetic emission. The source of the radiation is believed to be associated with the electron-positron (pair) plasma populating the pulsar magnetosphere. The theory of pulsar radiation is still in its infancy and there is lack of understanding about the energetic processes involved. The initial aim of this thesis is to study a possible emission mechanism in which electrostatic oscillations are coupled to propagating electromagnetic waves by a magnetic field inhomogeneity, thus creating a source of radiation in the pulsar magnetosphere. The full nonlinear equations in cylindrical geometry for a streaming cold pair plasma are solved numerically, together with Maxwell's equations, using a Finite-Difference Time Domain method. Electrostatic oscillations are induced in a streaming plasma in the presence of a non-uniform magnetic field, and the resulting electromagnetic waves are modelled self-consistently. Also presented is the linear perturbation analysis of these model equations perturbed from a dynamical equilibrium in order to probe the fundamental modes present in the system. These simulations successfully exhibit the coupling mechanism and the nonlinear interaction between electromagnetic waves and independent plasma oscillations, confirming the importance of coherent plasma effects and collective plasma processes in the pulsar magnetosphere. The observed electromagnetic signature is characterised by the nature of the emission mechanism and possibly by the menagerie of dust it encounters as it propagates through the surrounding supernova remnant. Supernova remnants are composed of multi-species electron-ion dusty plasmas. Conventional modelling of dust growth in this environment is based upon coagulation and nucleation of gas phase material. The second aim of this thesis is to study a possible spheroidal dust growth mechanism via plasma deposition. Dust grains immersed in a plasma acquire a net negative charge forming a plasma sheath. Ions are accelerated from the bulk plasma into the sheath and are deposited on the surface of the grain altering its shape and size. Grains with an elliptical geometry have a non-radial electric field and further anisotropic growth occurs if the deposited ions are non-inertial. In reality the extent of such growth depends upon the initial kinetic energy of the ions and the magnitude of the electric field in the sheath. Laplace's equation for the electric field for a range grain eccentricities is numerically solved using a bespoke finite difference method, the dynamics of the ions in the sheath are solved, showing how elliptical growth is related to the initial eccentricity and size of the seed relative to the sheath length.
Automated Contouring and Planning in Radiation Therapy: What Is ‘Clinically Acceptable’?

Developers and users of artificial-intelligence-based tools for automatic contouring and treatment planning in radiotherapy are expected to assess clinical acceptability of these tools. However, what is ‘clinical acceptability’? Quantitative and qualitative approaches have been used to assess this ill-defined concept, all of which have advantages and disadvantages or limitations. The approach chosen may depend on the goal of the study as well as on available resources. In this paper, we discuss various aspects of ‘clinical acceptability’ and how they can move us toward a standard for defining clinical acceptability of new autocontouring and planning tools.
CAKUT: A Pediatric and Evolutionary Perspective on the Leading Cause of CKD in Childhood

The global prevalence of chronic kidney disease (CKD) is increasing rapidly, due to increasing environmental stressors through the life cycle. Congenital anomalies of kidney and urinary tract (CAKUT) account for most CKD in children, with a spectrum that can lead to kidney failure from early postnatal to late adult life. A stressed fetal environment can impair nephrogenesis, now recognized as a significant risk factor for the development of adult CKD. Congenital urinary tract obstruction is the leading cause of CKD due to CAKUT and can itself impair nephrogenesis as well as contribute to progressive nephron injury. Early diagnosis by ultrasonography in fetal life by an obstetrician/perinatologist can provide important information for guiding prognosis and future management. This review focuses on the critical role played by the pediatrician in providing timely evaluation and management of the patient from the moment of birth to the transfer to adult care. In addition to genetic factors, vulnerability of the kidney to CKD is a consequence of evolved modulation of nephron number in response to maternal signaling as well as to susceptibility of the nephron to hypoxic and oxidative injury. Future advances in the management of CAKUT will depend on improved biomarkers and imaging techniques.
Artificial Intelligence Software for Diabetic Eye Screening: Diagnostic Performance and Impact of Stratification

Aim: To evaluate the MONA.health artificial intelligence screening software for detecting referable diabetic retinopathy (DR) and diabetic macular edema (DME), including subgroup analysis. Methods: The algorithm’s threshold value was fixed at the 90% sensitivity operating point on the receiver operating curve to perform the disease classification. Diagnostic performance was appraised on a private test set and publicly available datasets. Stratification analysis was executed on the private test set considering age, ethnicity, sex, insulin dependency, year of examination, camera type, image quality, and dilatation status. Results: The software displayed an area under the curve (AUC) of 97.28% for DR and 98.08% for DME on the private test set. The specificity and sensitivity for combined DR and DME predictions were 94.24 and 90.91%, respectively. The AUC ranged from 96.91 to 97.99% on the publicly available datasets for DR. AUC values were above 95% in all subgroups, with lower predictive values found for individuals above the age of 65 (82.51% sensitivity) and Caucasians (84.03% sensitivity). Conclusion: We report good overall performance of the MONA.health screening software for DR and DME. The software performance remains stable with no significant deterioration of the deep learning models in any studied strata.
An effective method based on reference point for glucose sensing at 1100-1600nm

Non-invasive blood glucose sensing by near-infrared spectroscopy is easily interrupted by the strong background variations compared to the weak glucose signals. In this work, according to the distribution of diffuse reflectance intensity at different source-detector separations, a method based on a reference point and a measuring point, where the diffuse reflectance intensity is insensitive and most sensitive to the variation of glucose concentration, respectively, is applied. And the data processing method based on the information of two points is investigated to improve the precision of glucose sensing. Based on the Monte Carlo simulation in 5% intralipid solution model, the corresponding optical probe is designed which includes two detecting points: a reference point located at 1.3-1.7mm and a measuring point located at 1.7-2.1mm. Using the probe, the in vitro experiment with different glucose concentrations in the intralipid solution is conducted at 1100-1600nm. As a result, compared to the PLS model built by the signal of the measuring point, the root mean square error of prediction (RMSEP) and root mean square error of cross calibration (RMSEC) of the corrected model built by reference point and measuring point reduces by 45.10%, and 32.15% respectively.
Novel Data Imputation for Multiple Types of Missing Data in Intensive Care Units

The diversity and number of parameters monitored in an intensive care unit (ICU) make the resulting databases highly susceptible to quality issues, such as missing information and erroneous data entry, which adversely affect the downstream processing and predictive modeling. Missing data interpolation and imputation techniques, such as multiple imputation, expectation maximization, and hot-deck imputation techniques do not account for the type of missing data, which can lead to bias. In our study, we first model the missing data as three types: “neglectable” also known as a.k. a “missing completely at random,” “recoverable” a.k. a. “missing at random,” and “not easily recoverable” a.k. a. “missing not at random. ” We then design imputation techniques for each type of missing data. We use a publicly available database (MIMIC II) to demonstrate how these imputations perform with random forests for prediction. Our results indicate that these novel imputation techniques outperformed standard mean filling techniques and expectation maximization with a statistical significance p ≤ 0.01 in predicting ICU mortality.
A Review on Surface-Enhanced Raman Scattering

Surface-enhanced Raman scattering (SERS) has become a powerful tool in chemical, material and life sciences, owing to its intrinsic features (i.e., fingerprint recognition capabilities and high sensitivity) and to the technological advancements that have lowered the cost of the instruments and improved their sensitivity and user-friendliness. We provide an overview of the most significant aspects of SERS. First, the phenomena at the basis of the SERS amplification are described. Then, the measurement of the enhancement and the key factors that determine it (the materials, the hot spots, and the analyte-surface distance) are discussed. A section is dedicated to the analysis of the relevant factors for the choice of the excitation wavelength in a SERS experiment. Several types of substrates and fabrication methods are illustrated, along with some examples of the coupling of SERS with separation and capturing techniques. Finally, a representative selection of applications in the biomedical field, with direct and indirect protocols, is provided. We intentionally avoided using a highly technical language and, whenever possible, intuitive explanations of the involved phenomena are provided, in order to make this review suitable to scientists with different degrees of specialization in this field.
Effects of the dipeptides comprising leucine and lysine on lifespan and age‐related stress in Caenorhabditis elegans

Abstract The aging process is affected by various stressors. An increase in oxidative stress is related to the impairment of physiological functions and enhancement of glycative stress. Food‐derived bioactive peptides have various physiological functions, including antioxidant activities. Dipeptides comprising Leu and Lys (LK and KL, respectively) have been isolated from foods; however, their physiological properties remain unclear. In this study, we investigated the antioxidant/antiglycation activity of dipeptides and their antiaging effects using Caenorhabditis elegans (C. elegans). Both dipeptides showed antioxidant activities against several reactive oxygen species (ROS) in vitro. In particular, the scavenging activity of LK against superoxide radicals was higher than KL did. Moreover, dipeptides suppressed advanced glycation end products (AGEs) formation in the BSA–glucose model. In the lifespan assays using wild‐type C. elegans, both LK and KL significantly prolonged the mean lifespan by 20.9% and 11.7%, respectively. In addition, LK decreased intracellular ROS and superoxide radical levels in C. elegans. Blue autofluorescence, an indicator of glycation in C. elegans with age, was also suppressed by LK. These results suggest that dipeptides, notably LK, show an antiaging effect by suppressing oxidative and glycative stress. Our findings suggest that such dipeptides can be used as a novel functional food ingredient. Food‐derived dipeptide Leu–Lys (LK) and Lys–Leu (KL) exert antioxidant and antiglycation activity in vitro. Treatment with LK prolonged the mean lifespan and maximum lifespan of C. elegans more than that of KL. Intracellular ROS and blue autofluorescence levels (indicator of aging) were suppressed by LK.
Antioxidant Thymoquinone and Its Potential in the Treatment of Neurological Diseases

Oxidative stress is one of the main pathogenic factors of neuron damage in neurodegenerative processes; this makes it an important therapeutic target to which the action of neuroprotectors should be directed. One of these drugs is thymoquinone. According to modern data, this substance has a wide range of pharmacological activity, including neuroprotective, which was demonstrated in experimental modeling of various neurodegenerative diseases and pathological conditions of the brain. The neuroprotective effect of thymoquinone is largely due to its antioxidant ability. Currently available data show that thymoquinone is an effective means to reduce the negative consequences of acute and chronic forms of cerebral pathology, leading to the normalization of the content of antioxidant enzymes and preventing an increase in the level of lipid peroxidation products. Antioxidant properties make this substance a promising basis for the development of prototypes of therapeutic agents aimed at the treatment of a number of degenerative diseases of the central nervous system.
Broad emission lines: A tool for studying nuclei of active galaxies

Active galactic nuclei (AGNs) are objects hosting in their center a super-massive black hole (SMBH) with an accretion disk surrounded by gas and dust. The mass of an SMBH can be derived from the dynamics of the gas gravitationally bounded to the SMBH. This is the case for the broad line region (BLR), i.e. a photoionized gas in the vicinity of an SMBH that emits broad emission lines (BELs), which properties can be used to estimate the mass of the SMBH. In spite of a number of papers devoted to the BLR research, its true nature is not well known. Therefore, it is still important to investigate the BLR structure (size, geometry, physics, etc.), where one of the aims is to better constrain the mass of the SMBH in the center of AGNs. The BELs are the only signatures of the BLR physics and geometry. They can be clearly identified in AGN spectra and they often show complex profiles. Their fluxes, profiles and ratios can provide much information about the BLR geometry and physics. Moreover, the BELs and continuum flux are very often varying in AGNs. Therefore, an investigation of the BEL flux and profile variability during a long period is another useful tool for mapping the geometrical and dynamical structure of the BLR. In this review we present and discuss some tools and techniques for studying the structure of the BLR using broad emission line properties.
Influence of Baseline Anemia on Dual Antiplatelet Therapy Cessation and Risk of Adverse Events After Percutaneous Coronary Intervention: Insights From the PARIS Registry

Background: Anemia is a well-recognized risk factor for both bleeding and ischemic events after percutaneous coronary intervention (PCI). We sought to determine the impact of baseline anemia on dual antiplatelet therapy (DAPT) cessation patterns ⩽2 years after PCI and the subsequent risk of clinical adverse events. Methods and Results: PARIS (Patterns of Non-Adherence to Dual Anti-Platelet Regimen in Stented Patients) was a prospective multicenter observational registry of PCI-treated patients (n=5018). Anemia was defined as baseline Hb (hemoglobin) <12 g/dL for men and <11 g/dL for women. DAPT cessation modes included physician-recommended discontinuation, temporary interruption (⩽14 days), and disruption due to bleeding or noncompliance. The primary end point was 2-year major adverse cardiovascular events (MACE), a composite of cardiac death, myocardial infarction, or target vessel revascularization. We identified 824 (18%) anemic and 4194 (82%) nonanemic patients. Anemic patients were older and had a higher rate of diabetes mellitus, hypertension, and prior PCI. DAPT interruption and disruption were significantly more common in anemic patients throughout 2 years after PCI, whereas physician-recommended discontinuation occurred more often in anemic patients during the first year after PCI and in nonanemic patients during the second year. The 2-year adjusted risks of MACE and Bleeding Academic Research Consortium 3 or 5 bleeding events were significantly higher in anemic patients. Compared with uninterrupted DAPT, disruption, but not interruption and physician-recommended discontinuation, was associated with a higher risk of myocardial infarction in nonanemic patients and a higher risk of both myocardial infarction and MACE in anemic patients. There was no significant interaction between anemia and risk of clinical outcomes associated with each DAPT cessation mode. Conclusions: Baseline anemia was associated with a significantly higher adjusted risk of MACE and major bleeding. Physicians more frequently recommend DAPT discontinuation to anemic patients during the first year, and to nonanemic patients during the second year after PCI. DAPT disruption was associated with a higher risk of MACE outcomes.
The Ultraviolet Continuum Emission of FR I and FR II Radio Galaxies and a Proposal for a Unified AGN Model for FR I sources

This paper is the second in a series of two on the UV continuum emission (in the range from 1400 to 3700 Å) of radio galaxies that were extracted from the Hubble Space Telescope (HST) Archives. The sample consists of 31 3C and Parkes radio galaxies that have redshifts below 0.2 (the majority have redshifts of ~0.03) and radio powers of ~1025–1027 W Hz-1 (using H0 = 50 km-1 s-1 Mpc and q0 = 0.0). Paper I describes the sample selection and the properties of individual sources; this paper deals with the analysis. We find that only about half the radio galaxies display any UV flux at wavelengths shorter than 2300 Å. More specifically, those galaxies that are dominated by a nuclear UV component are either BL Lac objects or radio galaxies with broad emission lines. We detect a nuclear and an extended UV component only among half the radio galaxies with narrow emission lines. Although we do not find a correlation of the UV luminosity with emission-line luminosity or radio power, there does appear to be a dependence on radio morphology. While (narrow line) FR II sources do not show a nuclear UV component, FR I's do, however, only if they also have an optical jet (this is the case for seven of 21 FR I's). These results are broadly consistent with orientation-dependent unification models. In radio galaxies in which the torus does not obscure our view of the engine, the observed UV radiation appears to be point source–like. This is the case for broad-line radio galaxies and BL Lac objects. In other radio galaxies that are oriented at an angle to us, the torus presumably blocks the nuclear UV component. The narrow-line FR I galaxies with optical jets can then be interpreted as objects at a critical angle at which some, but not all, nuclear UV emission is blocked. The UVλ luminosities (with λ ranging from 1400 to 3700 Å) and the UVλ-V colors of radio galaxies show a larger scatter than those of radio-quiet elliptical galaxies. At wavelengths shorter than 2300 Å, some radio galaxies have on average bluer colors, but beyond 3000 Å, their colors are on average slightly redder. This picture is also consistent with unification models—the galaxies with bluer colors are either BL Lac objects or broad-line radio galaxies. All other radio galaxies (including the jetted FR I's) have somewhat redder colors than radio-quiet elliptical galaxies. We suspect that this is primarily due to reddening by dust, which we know is present in some of the radio galaxies in the sample. At longer wavelengths (>3000 Å), all radio galaxies (14 of 14) show an extended component. The morphology of the extended emission is in most, but not all, cases comparable to the morphology at optical wavelengths, implying that this is likely to be starlight. However, the polarization images of two of seven radio galaxies indicate that scattered light from the active galactic nucleus may also contribute toward the UV luminosity.
Facilitating perception of speech in babble through conceptual relationships

Speech perception is influenced by many different sources of information. Here we examine whether auditorily presented conceptual/semantic information facilitates the perception of degraded speech. To this end, acoustically clear sentences preceded sentences presented in speech babble. These sentence pairs were either conceptually related, conceptually unrelated, or the same. The conceptually related and unrelated sentence pairs did not share any content words. Behavioral results show the highest accuracy for the same condition, followed by the conceptually related condition. The worst performance was in the unrelated condition. We then examined the neural substrates of this effect using fMRI. Preliminary results show that a direct contrast between related and unrelated sentences recruits a semantic/conceptual network including fronto-parietal and subcortical areas. The same sentence pair condition showed relatively greater activation in the superior temporal gyrus compared to the other two conditions. Th.
Distortion sensitivity of estimators of location

Robustness measures and procedures have traditionally been developed and implemented through the contamination model of Hampel et al. [2005, Robust Statistics: The Approach Based on Influence Functions, Wiley Series in Probability and Statistics (Vol. 114), New York: Wiley]. We present a distortion model that takes a symmetric probability density function and skews it infinitesimally in a specific direction thereby distorting every realisation of the distribution, a model based upon the work of Fechner [1897, ‘Th. (1897)’, in Kollektivmasslehre, Leipzig: Engelman]. Robustness to distortion of a symmetric signal is determined as the rate of change of the functional of an affine-equivariant location estimator under the Fechner model. The mean, median and Hodges–Lehman estimators are compared under this model.
A carrier injection type optical switch in GaAs using free carrier plasma dispersion with wavelength range from 1.06 to 1.55 mu m

The switching current for the device is about 90 mA at all in-range wavelengths. Its broad wavelength range is suitable for optical signal-processing applications in wavelength-division multiplexing transmission systems. High coupling efficiency to a single-mode fiber is achieved by using a small- Delta waveguide structure with carrier blocking layers. The effective refractive index change in the waveguide per unit of the injected current density is doubled by the carrier blocking layers without reducing coupling efficiency. >
Reduction of numerical diffusion in three-dimensional vortical flows using a coupled Eulerian/Lagrangian solution procedure

A new approach based on the coupling of an Eulerian and a Lagrangian solver, aimed at reducing the numerical diffusion errors of standard Eulerian time-marching finite-volume solvers, is presented. The approach is applied to the computation of the secondary flow in two bent pipes and the flow around a 3D wing. Using convective point markers the Lagrangian approach provides a correction of the basic Eulerian solution. The Eulerian flow in turn integrates in time the Lagrangian state-vector. A comparison of coarse and fine grid Eulerian solutions makes it possible to identify numerical diffusion. It is shown that the Eulerian/Lagrangian approach is an effective method for reducing numerical diffusion errors.