Miracle-dz/UniFAR-FTUs huggingface dataset:
The Casimir force in the semi-classical regime

The present thesis is devoted to a detailed study of the Casimir force exerting between two parallel metallic plates whose conducting behaviour is described on the microscopic level. In the semi-classical regime, which corresponds to large separations and high temperatures, the theoretical value of this force – which exhibits a universal character – is subject to a controversy revolving around a factor 2. Current theories describe the plates macroscopically or semi-macroscopically and impose perfect boundary conditions to the field at their interface. In a statistical mechanical framework, we perform a direct calculation of the average force exerting between the fluctuating charges of a two-slab system in the semi-classical regime. In a first model, the charges are classical. The calculation is then generalised to quantum plasmas coupled to the radiation field, by means of path integral formalism. Relying on these accurate models, we can pronounce on the correct value of the force. In addition, we explain its universality as being the result of perfect screening mechanisms reflecting the effective shielding of the charges in the conductors. We conclude that although shielded, charge fluctuations inside the conductors cannot be neglected.
Universal quantized thermal conductance in graphene

We have demonstrated the universal topological order in graphene quantum Hall by measuring quantum limit of thermal conductance. The universal quantization of thermal conductance provides information on a state's topological order. Recent measurements revealed that the observed value of thermal conductance of the 52 state is inconsistent with either Pfaffian or anti-Pfaffian model, motivating several theoretical articles. Analysis has been made complicated by the presence of counter-propagating edge channels arising from edge reconstruction, an inevitable consequence of separating the dopant layer from the GaAs quantum well and the resulting soft confining potential. Here, we measured thermal conductance in graphene with atomically sharp confining potential by using sensitive noise thermometry on hexagonal boron-nitride encapsulated graphene devices, gated by either SiO2/Si or graphite back gate. We find the quantization of thermal conductance within 5% accuracy for ν = 1;43;2 and 6 plateaus, emphasizing the universality of flow of information. These graphene quantum Hall thermal transport measurements will allow new insight into exotic systems like even-denominator quantum Hall fractions in graphene.
Evaluation of Zif-8 Flexible Force Fields for Structural and Mechanical Properties

Metal–Organic Frameworks (MOFs) offer considerable potential for applications in adsorption due to their large pore volumes and surface areas. Studies on mechanical stability of MOFs are scarce. Seminal experimental work has shed a new light on the role that elastic constants play in establishing the structural stability of the prototypical ZIF-8 MOF
Numerical generation of a vortex ring cascade in quantum turbulence

A symmetric anti-parallel quantum pair of vortices is simulated using the three-dimensional Gross-Pitaevski equations. The initial development before cores interact directly demonstrates the traditional vortex dynamics of stretching, curvature and torsion in a manner consistent with a filament calculation and simulations of the classical, ideal Euler equations. Once the cores begin to interact, reconnection develops in the vacuum that forms between the pair. Out of the reconnection region, vortex waves are emitted with properties similar to waves in the local induction approximation. These waves propagate down the initial vortex and deepen. When they deepen far enough, secondary reconnections occur and vortex rings form. Near this time, spectra have a $k^{-3}$ regime. As the vortex rings fully separate, the high wavenumber spectra grow until, at the final time simulated, spectra in two directions develop nearly -5/3 subranges. This occurs without the dissipation of energy. Preliminary analysis of the flow of energies in spectral scale and physical space is discussed.
Spin-Orbit Torque and Magnetic Damping in Tailored Ferromagnetic Bilayers

We study spin-orbit-torque-driven ferromagnetic resonance (FMR) in ferromagnetic (FM) bilayers, consisting of Co and permalloy (Py), sandwiched between Pt and MgO layers. We find that the FM layer in contact with the Pt layers dominantly determines that spin Hall angle, which is consistent with the spin-transparency model. By contrast, the FMR linewidths are considerably influenced not only by the spin-pumping effect across the Pt|FM in terface but also by the spin relaxation such as two-magnon scattering at the FMMgO interface.The CoMgO interface leads to notably increased FMR linewidths, while the Py|MgO interface has less effect. This different contribution of each interface to the spin Hall angel and dissipation parameter suggests that the stack configuration of Pt|Co|Py|MgO requires less writing energy than Pt|Py|Co|MgO in spin-orbit-torque-driven magnetic switching. Our approach offers a promising method to optimize material parameters by engineering either interfaces in contact with the heavy-metal or the oxide layer.
Which Parametric Model for Conditional Skewness

This paper addresses an existing gap in the developing literature on conditional skewness. We develop a simple procedure to evaluate parametric conditional skewness models. This procedure is based on regressing the realized skewness measures on model-implied conditional skewness values. We find that an asymmetric generalized autoregressive conditional heteroscedasticity specification on shape parameters with a skewed generalized error distribution provides the best in-sample fit for the data, as well as reasonable predictions of the realized skewness measure. Our empirical findings imply significant asymmetry with respect to positive and negative news in both conditional asymmetry and kurtosis processes.
Integrated and Resolved Dust Attenuation in Clumpy Star-Forming Galaxies at 0.07 < $z$ < 0.14

Dust attenuation in galaxies has been extensively studied nearby, however, there are still many unknowns regarding attenuation in distant galaxies. We contribute to this effort using observations of star-forming galaxies in the redshift range z = 0.05-0.15 from the DYNAMO survey. Highly star-forming DYNAMO galaxies share many similar attributes to clumpy, star-forming galaxies at high redshift. Considering integrated Sloan Digital Sky Survey observations, trends between attenuation and other galaxy properties for DYNAMO galaxies are well matched to star-forming galaxies at high redshift. Integrated gas attenuations of DYNAMO galaxies are 0.2-2.0 mags in the V-band, and the ratio of stellar E(B-V) and gas E(B-V) is 0.78-0.08 (compared to 0.44 at low redshift). Four highly star-forming DYNAMO galaxies were observed at H-alpha using the Hubble Space Telescope and at Pa-alpha using integral field spectroscopy at Keck. The latter achieve similar resolution (~0.8-1 kpc) to our HST imaging using adaptive optics, providing resolved observations of gas attenuations of these galaxies on sub-kpc scales. We find < 1.0 mag of variation in attenuation (at H-alpha) from clump to clump, with no evidence of highly attenuated star formation. Attenuations are in the range 0.3-2.2 mags in the V band, consistent with attenuations of low redshift star-forming galaxies. The small spatial variation on attenuation suggests that a majority of the star-formation activity in these four galaxies occurs in relatively unobscured regions and, thus, star-formation is well characterised by our H-alpha observations.
Destruction of Refractory Carbon in Protoplanetary Disks

The Earth and other rocky bodies in the inner solar system contain significantly less carbon than the primordial materials that seeded their formation. These carbon-poor objects include the parent bodies of primitive meteorites, suggesting that at least one process responsible for solid-phase carbon depletion was active prior to the early stages of planet formation. Potential mechanisms include the erosion of carbonaceous materials by photons or atomic oxygen in the surface layers of the protoplanetary disk. Under photochemically generated favorable conditions, these reactions can deplete the near-surface abundance of carbon grains and polycyclic aromatic hydrocarbons by several orders of magnitude on short timescales relative to the lifetime of the disk out to radii of ∼20–100+ au from the central star depending on the form of refractory carbon present. Due to the reliance of destruction mechanisms on a high influx of photons, the extent of refractory carbon depletion is quite sensitive to the disk’s internal radiation field. Dust transport within the disk is required to affect the composition of the midplane. In our current model of a passive, constant-α disk, where α = 0.01, carbon grains can be turbulently lofted into the destructive surface layers and depleted out to radii of ∼3–10 au for 0.1–1 μm grains. Smaller grains can be cleared out of the planet-forming region completely. Destruction may be more effective in an actively accreting disk or when considering individual grain trajectories in non-idealized disks.
The Impact of Volatile Chemical Products, Other VOCs, and NOx on Peak Ozone in the Lake Michigan Region

High concentrations of ozone along the coastline of Lake Michigan are a persistent air quality management challenge. Complementing observations during the 2017 Lake Michigan Ozone Study (LMOS 2017), WRF‐Chem modeling was used to quantify sensitivity of modeled ozone (O3) to anthropogenic nitrogen oxides (NOx) and volatile organic compound (VOC) emissions, including to changes in volatile chemical product (VCP). The daily maximum 8 hr average (MDA8) over the high ozone region of Lake Michigan decreased by 2.7 ppb with exclusion of VCP from the inventory, and was sensitive to both NOx and VOC changes, with greater sensitivity to NOx. Close to urban centers, MDA8 ozone was VOC‐sensitive. Clusters of coastal receptor sites were identified based on similarity in response to emission perturbations, with most clusters being NOx‐sensitive and NOx‐sensitivity increasing with distance from major emission sources. The 2 June 2017 ozone event, which has received considerable focus, is shown to be atypical due to unusually strong and spatially extended VOC‐sensitive behavior. WRF‐Chem integrated reaction rate analysis was used to compute radical termination rates due to NOx (LNOx) and to radical‐radical reactions (LROx). LROx/LNOx and formaldehyde to NO2 ratio (FNR) were shown to be predictive of modeled MDA8 ozone sensitivity, but with variation in predictive power as a function of time of day, which has implications for air quality management use of FNR from geostationary satellites.
Development of Conceptual Change Theory-Based E-Modules Equipped with Conceptual Change Texts on the Solar System Topics

This study aims to develop a set of e-module teaching materials equipped with conceptual change text based on conceptual change theory on the Solar System materials. The research method used was Educational Design Research (EDR) with the Plomp model. The research consisted of three stages, namely the preliminary study, design development and product testing. At the initial stage, an analysis of competencies, essential materials, and misconceptions experienced by students in the Solar System material was carried out. There were major misconceptions such as the Sun as the biggest star, the motion of the planets that are always the same, the phases of the moon, revolution and rotation of the earth, Kepler's Laws II and III, solar eclipses, and Newton's gravity that occurs between the earth and the moon as well as the earth and the sun. These findings are the basis for developing the e-module. Based on the validation and practicality tests, the validation level was obtained at 3.85 which means very valid category and practicality at 93% means very practical category. Therefore, it can be concluded that the developed e-module teaching materials based on the conceptual change on the Solar System topics are valid and practical.
Identification of Human Gut Microbiome Associated with Enterolignan Production

Dietary plant lignans are converted inside the gut to enterolignans enterodiol (ED) and enterolactone (EL), which have several biological functions, and health benefits. In this study, we characterized the gut microbiome composition associated with enterolignan production using data from a cross-sectional study in the Japanese population. We identified enterolignan producers by measuring ED and EL levels in subject’s serum using liquid chromatography-tandem mass spectrometry. Enterolignan producers show more abundant proportion of Ruminococcaceae and Lachnospiraceae than non-enterolignan producers. In particular, subjects with EL in their serum had a highly diverse gut microbiome that was rich in Ruminococcaceae and Rikenellaceae. Moreover, we built a random forest classification model to classify subjects to either EL producers or not using three characteristic bacteria. In conclusion, our analysis revealed the composition of gut microbiome that is associated with lignan metabolism. We also confirmed that it can be used to classify the microbiome ability to metabolize lignan using machine learning approach.
Process Development of Polyhydroxyalkanoates Production by Halophiles Valorising Food Waste

Polyhydroxyalkanoates (PHA) is an emerging biodegradable plastic family that can replace a broad spectrum of conventional thermoplastics and is promising in the sustainable process development and valorization of organic waste. This study established a novel production system of PHA from food waste through halophilic microbial fermentation with spent medium recycling. The essential processing parameters for batch cultivation of Haloferax mediterranei were optimized for food waste substrate (a 40 g/L loading and 2.5 vvm of aeration), which achieved a yield of 0.3 g PHA/g COD consumed. A batch bioreactor system was developed, which produced 7.0 ± 0.7 g/L cell dry mass and 4.5 ± 0.2 g/L PHA with a 20% dissolved oxygen (DO) level. A DO above 50% saturation resulted in faster cell growth and similar cell mass production but 25% less PHA production. The spent saline medium, treated with H2O2 and rotary evaporation, was successfully reused for four consecutive batches and provided consistent PHA concentrations and product qualities.
Determination and Mapping of the Causes of High Risk of Earthquake Hazards Using Geoelectrical Data in Bengkaung, Batu Layar, West Lombok Indonesia

The Bengkaung area, Batulayar District, West Lombok is suspected to be very vulnerable to the risk of earthquake hazards. However, in this area no scientific research, either geological or geophysical, has ever been carried out regarding this hazard. How are the physical characteristics of the lithology and structure in the area to the risk of earthquake disaster? The purpose of this study was to determine the physical characteristics of the lithology and subsurface structures that were validated by the level of damage. The method used is the geoelectric method and local building damage data. The results of the 2D geoelectric anomaly modeling show the characteristics of the subsurface lithological layers in the form of sand, sandstone, clay, andesite lava faults, fresh andesite lava, and granite. The fault was detected in the center of the study area in a north-south direction. Earthquake hazard analysis shows that the cause of the high risk of earthquake hazard in Bengkaung Village is the presence of faults and cohesive lithology. The highest potential risk is in the southern part of Bengkaung Village. The southern area of ​​Bengkaung Village is dominated by clay that has cohesive properties, especially on the surface. The western and northern parts of Bengkaung Village have medium and low vulnerability to earthquake hazards. The last two areas are dominated by non-cohesive soils in the form of sandy soils and lapilli pumice
Effects of Dermatan Sulfate from Marine Invertebrate Styela plicata in the Wound Healing Pathway: A Natural Resource Applied to Regenerative Therapy

Acute and chronic dermatological injuries need rapid tissue repair due to the susceptibility to infections. To effectively promote cutaneous wound recovery, it is essential to develop safe, low-cost, and affordable regenerative tools. Therefore, we aimed to identify the biological mechanisms involved in the wound healing properties of the glycosaminoglycan dermatan sulfate (DS), obtained from ascidian Styela plicata, a marine invertebrate, which in preliminary work from our group showed no toxicity and promoted a remarkable fibroblast proliferation and migration. In this study, 2,4-DS (50 µg/mL)-treated and control groups had the relative gene expression of 84 genes participating in the healing pathway evaluated. The results showed that 57% of the genes were overexpressed during treatment, 16% were underexpressed, and 9.52% were not detected. In silico analysis of metabolic interactions exhibited overexpression of genes related to: extracellular matrix organization, hemostasis, secretion of inflammatory mediators, and regulation of insulin-like growth factor transport and uptake. Furthermore, in C57BL/6 mice subjected to experimental wounds treated with 0.25% 2,4-DS, the histological parameters demonstrated a great capacity for vascular recovery. Additionally, this study confirmed that DS is a potent inducer of wound-healing cellular pathways and a promoter of neovascularization, being a natural ally in the tissue regeneration strategy.
Protective and Vulnerability Factors of Municipal Workers’ Mental Health: A Cross-Sectional Study

Work is fundamental to an individual’s mental health; however, an unfavourable work environment can lead to mental health problems. Despite existing studies addressing workers’ mental health, it is essential to understand the reality of specific contexts to design effective tailored interventions. Thus, this study aimed to examine the influence of potential protective and vulnerability factors on municipal workers’ depressive symptoms, anxiety and stress levels, and burnout. A cross-sectional study was conducted with data collection performed between July and December 2021 using online self-report measures. The sample comprised 115 municipal workers. The findings revealed that psychological vulnerability is a significant vulnerability factor for the presence of mental health symptoms. In addition, job satisfaction was found to be a significant protective factor for depressive symptoms, anxiety, and burnout of the municipal workers. The results of this study enhance the understanding of factors that influence worker mental health, which may facilitate the proper planning of specific interventions to promote mental health in the workplace.
HATS-43b, HATS-44b, HATS-45b, and HATS-46b: Four Short-period Transiting Giant Planets in the Neptune–Jupiter Mass Range

We report the discovery of four short-period extrasolar planets transiting moderately bright stars from photometric measurements of the HATSouth network coupled to additional spectroscopic and photometric follow-up observations. While the planet masses range from 0.26 to 0.90 , the radii are all approximately a Jupiter radii, resulting in a wide range of bulk densities. The orbital period of the planets ranges from 2.7 days to 4.7 days, with HATS-43b having an orbit that appears to be marginally non-circular (e = 0.173 ± 0.089). HATS-44 is notable for having a high metallicity ( = 0.320 ± 0.071). The host stars spectral types range from late F to early K, and all of them are moderately bright (13.3 < V < 14.4), allowing the execution of future detailed follow-up observations. HATS-43b and HATS-46b, with expected transmission signals of 2350 ppm and 1500 ppm, respectively, are particularly well suited targets for atmospheric characterization via transmission spectroscopy.
Abundances of the light elements from UV (HST) and red (ESO) spectra in the very old star HD 84937

In order to provide a better basis for the study of mechanisms of nucleosynthesis of the light elements beyond hydrogen and helium in the oldest stars, the abundances of C, O, Mg, Si, P, S, K, and Ca have been derived from UV-HST and visible-ESO high resolution spectra in the old, very metal-poor star HD 84937, at a metallicity that is 1/200 that of the Sun's. For this halo main-sequence turnoff star, the abundance determination of P and S are the first published determinations. The LTE profiles of the lines were fitted to the observed spectra. Wherever possible, we corrected the derived abundances for non-LTE effects. Three-dimensional (3D) CO5BOLD model atmospheres have been used to determine the abundances of C and O from molecular CH and OH bands. The abundances of these light elements in HD 84937 are found to agree well with the abundances in classical metal-poor stars. Our HD 84937 carbon abundance determination points toward a solar (or mildly enhanced) value of [C/Fe]. The modest overabundance of the alpha elements of even atomic number Z, typical of halo turnoff stars, is confirmed in this example. The odd-Z element P is found to be somewhat deficient in HD 84937, at [P/Fe]=-0.32, which is again consistent with the handful of existing determinations for turnoff stars of such low metallicity. We show that the abundance of oxygen, deduced from the OH band from 3D computations, is not compatible with the abundance deduced from the red oxygen triplet. This incompatibility is explained by the existence of a chromosphere heating the shallow layers of the atmosphere where the OH band, in 3D computations, is mainly formed. The abundance ratios are compared to the predictions of models of galactic nucleosynthesis and evolution