Miracle-dz/UniFAR-FTUs huggingface dataset:
Energy-Efficient User Association in mmWave/THz Ultra-Dense Network via Multi-Agent Deep Reinforcement Learning

As a key enabler for 5G and 6G wireless communications, millimeter-wave (mmWave) and terahertz (THz) ultra-dense network (UDN) has received a great deal of attention recently. The mmWave/THz UDN can greatly improve the capacity of cellular network by exploiting the reduced path loss of densified network and the wide range of frequency spectrum. In order to maximize the capacity gain of UDN, the associations between small base stations (SBSs) and users should be designed deliberately. However, since computational complexity and signaling overhead increase exponentially with the numbers of SBSs and users, it is very difficult to apply the conventional centralized approaches in the UDN. In this paper, we propose a decentralized user association technique based on multi-agent actor-critic (AC) to maximize the energy efficiency of UDN. In our technique, actor network determines the user association of the SBS using the local observation and critic network informs the energy-efficient user association decision to the actor network. In doing so, the DRL agent in each SBS can find out the user association decision maximizing the network energy efficiency. From the extensive simulations, we demonstrate that the proposed scheme achieves more than 50% average energy efficiency gain over the conventional user association techniques.
Temporary Migrants as Dehumanised ‘Other’ in the Time of COVID-19: We’re All in This Together?

Temporary migrants comprise a substantial component of the Australian workforce. Evidence of the tensions and contradictions in Australia’s reliance on temporary migrant workers was spotlighted during the COVID-19 global health crisis, particularly with regards to the actions and responsibilities of key players in the attraction, recruitment, deployment and ultimately abandonment of these workers. In this article, we interrogate the public framing of temporary migrant workers within the context of the pandemic. We employ a discourse analysis and build upon theories of precarity and dehumanisation. In doing so we demonstrate how the precarious state within which temporary migrant workers found themselves saw them cast as a dehumanised and unwelcome ‘other’, a burden to the labour market, the state and the broader society.
Fine-tuning of the spectral efficiency based on tunneling splitting in multiple quantum well system

Transmission studies for quantum well (QW) structures composed by two-dimension photonic crystals are presented. The results indicate that, with the multiple QW structure, each resonant peak which appears in the single QW structure would split, and the splitting times increases in step with the increasing number of the wells. It is also found that the frequency spacing between adjacent splitting spectra can be finely tuned by adjusting the barrier widths properly, leading to great improvement of spectral efficiency. The physical explanation of the origin of the spectral splitting are provided. These results provide the prospects in super dense wavelength division multiplexing for optical communication and precise optical measurement for the purpose of maximization of channel density.
Tunable Photoresponse in a Two-Dimensional Superconducting Heterostructure

The photo-induced superconducting phase transition is widely used in probing the physical properties of correlated electronic systems and to realize broadband photodetection with extremely high responsivity. However, such photoresponse is usually insensitive to electrostatic doping due to the high carrier density of the superconductor, restricting its applications in tunable optoelectronic devices. In this work, we demonstrate the gate voltage modulation to the photoresponsivity in a two-dimensional NbSe2-graphene heterojunction. The superconducting critical current of the NbSe2 relies on the gate-dependent hot carrier generation in graphene via the Joule heating effect, leading to the observed shift of both the magnitude and peak position of the photoresponsivity spectra as the gate voltage changes. This heating effect is further confirmed by the temperature and laser-power-dependent characterization of the photoresponse. In addition, we investigate the spatially-resolved photocurrent, finding that the superconductivity is inhomogeneous across the junction area. Our results provide a new platform for designing tunable superconducting photodetector and indicate that the photoresponse could be a powerful tool in studying the local electronic properties and phase transitions in low-dimensional superconducting systems.
Tangencies and the Conley index

We construct an algebraic method for detecting bifurcations of discrete dynamical systems using the Conley index theory. We define the transition matrix pair for discrete semidynamical systems, which detects bifurcations of connecting orbits. As an application, we give a sufficient condition for the occurrence of homoclinic and heteroclinic tangencies by showing that the occurrence of a heterodimensional cycle in the projectivization of a dynamical system implies the tangency of the original system.
Comparison of Two Approaches for Handling Missing Covariates in Logistic Regression

For the past 25 years, methodological advances have been made in missing data treatment. Most published work has focused on missing data in dependent variables under various conditions. The present study seeks to fill the void by comparing two approaches for handling missing data in categorical covariates in logistic regression: the expectation-maximization (EM) method of weights and multiple imputation (MI). Sample data are drawn randomly from a population with known characteristics. Missing data on covariates are simulated under two conditions: missing completely at random and missing at random with different missing rates. A logistic regression model was fit to each sample using either the EM or MI approach. The performance of these two approaches is compared on four criteria: bias, efficiency, coverage, and rejection rate. Results generally favored MI over EM. Practical issues such as implementation, inclusion of continuous covariates, and interactions between covariates are discussed.
Genome-wide association mapping of bread wheat genotypes using yield and grain morphology-related traits under different environments

Depleting water resources and increasing global temperature due to climate change are major challenges to agriculture and food security worldwide. Deciphering the underlying mechanisms of traits contributing to grain development and yield is essential for the development of climate-resilient cultivars. Therefore, this study assessed 105 bread wheat genotypes grown under control, drought, and heat-stress conditions for two crop seasons and performed a genome-wide association study (GWAS) using a 90k SNP array. The genotypes showed significant trait differences under all environmental conditions. Highly significant variation was observed, with moderate (50.09%) to high (76.19%) heritability in the studied germplasms. The studied traits were all also significantly positively correlated. A total of 541 significant associations (p ≤ 10−3) between marker and trait (MTAs) were observed after crossing the FDR <0.05 threshold for all traits. Among these, 195, 179, and 167 significant MTAs were detected under control, drought, and heat-stress conditions, respectively. Under the control and drought conditions, pleiotropic loci BS00010616_51 and BS00010868_51 were observed on chromosomes 7B and 1B situated at 186.24 cM and 35.47 cM, respectively. Pleiotropic loci BS00010868_51, Kukri_c11154_1723, and Ex_c10068_1509 were identified on chromosomes 1B, 5B, and 2A, respectively, under control and heat stress conditions. A stable and consistent locus (Excalibur_c20796_395) on chromosome 7A, located at 372.34 cM, was also linked to grain morphology and yield-related attributes in control, drought, and heat-stress conditions. The results of the current study confirmed several previously reported MTAs for the traits under consideration and identified new MTAs under harsh climatic conditions. These SNPs will aid in the discovery of novel genes in wheat. SNPs showing significant associations may be used in marker-assisted selection and allow the development of drought- and heat-tolerant genotypes with high yields to address global food security concerns.
Effects of (P, N) dual acceptor doping on band gap and p-type conduction behavior of ZnO films

A reproducible p-type P-N codoped ZnO [ZnO:(P, N)] film with high quality was achieved by magnetron sputtering and post-annealing techniques. It has room-temperature resistivity of 3.98 Ωcm, Hall mobility of 1.35 cm2/Vs, and carrier concentration of 1.16 × 1018 cm−3, which is better than electrical properties of the p-type N-doped ZnO (ZnO:N) and p-type P-doped ZnO (ZnO:P) films. Additionally, the p-ZnO:(P, N)/n-ZnO homojunction showed a clear p-n diode characteristic. The p-type conductivity of ZnO:(P, N) is attributed to the formation of an impurity band above the valance band maximum, resulting in a reduction in the band gap and a decrease in the ionization energy of the acceptor, as well as an improvement in the conductivity and stability of the p-type ZnO:(P, N).
Racial and Ethnic Differences in the Protective Effect of Educational Attainment on Chronic Pain

Background: The broad scientific community generally associates high socioeconomic status (SES) with better health. However, the protective effects of high educational attainment on health may be weaker for racial and ethnic minorities than non-Latino White individuals. It is important to study whether this difference holds for chronic pain among Black and Latino individuals. Objectives: To compare the association between educational attainment and chronic pain in the US, considering the racial and ethnic background of individuals. Methods: The current study used baseline data from the Population Assessment of Tobacco and Health (PATH-Adults) study. All participants were 18+years old. A total number of 28204 Non-Latino, Latino, White, and Black individuals were enrolled. The outcome was chronic pain treated as a continuous measure. The predictor was educational attainment. Moderators were race and ethnicity. Results: Our linear regressions in the pooled sample showed that higher educational attainment was associated with a lower level of chronic pain; however, this association was weaker for Latinos and Blacks compared to non-Latino and White individuals. Our stratified models also showed that higher educational attainment was more consistently associated with a lower level of chronic pain for non-Latino White individuals than racial and ethnic minorities. Conclusion: The presumed protective effect of educational attainment against chronic pain among individuals varies between different racial and ethnic groups. Future research should test the role of stressful jobs and working conditions in weakening the protective effects of SES against chronic pain for Blacks and Latinos compared to non-Latino White individuals.
Highly NH3 Sensitive and Selective Ti3C2O2-Based Gas Sensors: A Density Functional Theory-NEGF Study

Ammonia (NH3) detection at the early stage is an important precaution for human health and agricultural production. However, conventional sensing materials are difficult to achieve all the targeted operational performances such as low power consumption and high selectivity. MXenes are a type of graphene-like emergent material equipped with abundant surface sites benefiting gas-sensing applications. In the work, we discuss the sensing performance of Ti3C2O2 to anticipate harmful and polluting NH3 gases by density functional theory and nonequilibrium Green’s function. The adsorption geometry, charge difference density, and partial density of states are discussed to understand the nature of interactions between gas molecules and Ti3C2O2. The theoretical results show that only NH3 adsorbs onto the nanosheet through chemisorption. Then, a two-electrode Ti3C2O2-based gas sensor device is built to unravel the transport properties. Current under different bias voltages indicates the Ti3C2O2-based sensor could maintain extremely high sensitivity, demonstrating that Ti3C2O2 has great potential for the NH3 sensor with high selectivity, excellent sensitivity, and low energy consumption. Upon external electric fields, the adsorption energy and charge transfer can be tuned effectively, suggesting that Ti3C2O2 is a versatile agent as an ammonia-sensing material.
Effects of Various Ripening Media on the Mesoporous Structure and Morphology of Hydroxyapatite Powders

Mesoporous hydroxyapatite (HA) materials demonstrate advantages as catalysts and as support systems for catalysis, as adsorbent materials for removing contamination from soil and water, and as nanocarriers of functional agents for bone-related therapies. The present research demonstrates the possibility of the enlargement of the Brunauer–Emmett–Teller specific surface area (SSA), pore volume, and average pore diameter via changing the synthesis medium and ripening the material in the mother solution after the precipitation processes have been completed. HA powders were investigated via chemical analysis, X-ray diffraction analysis, Fourier-transform IR spectroscopy, transmission electron microscopy (TEM), and scanning (SEM) electron microscopy. Their SSA, pore volume, and pore-size distributions were determined via low-temperature nitrogen adsorption measurements, the zeta potential was established, and electron paramagnetic resonance (EPR) spectroscopy was performed. When the materials were synthesized in water–ethanol and water–acetone media, the SSA and total pore volume were 52.1 m2g−1 and 116.4 m2g−1, and 0.231 and 0.286 cm3g−1, respectively. After ripening for 21 days, the particle morphology changed, the length/width aspect ratio decreased, and looser and smaller powder agglomerates were obtained. These changes in their characteristics led to an increase in SSA for the water and water–ethanol samples, while pore volume demonstrated a multiplied increase for all samples, reaching 0.593 cm3g−1 for the water–acetone sample.
Performance verification of the MIRI imager flight model at CEA

MIRIM is the imager of the Mid Infrared Instrument (MIRI), one of the three scientific instruments on the James Webb Space Telescope (JWST). MIRIM will provide imaging between 5. 6μm and 25. 5μm, low resolution spectroscopy (LRS) between 5 and 10μm, and coronagraphy at 10. 65μm, 11. 4μm, 15. 5μm and 23μm. The Optical bench Assembly of MIRIM Flight Model (FM) has been integrated and tested between 2008 and 2009 at CEA (Saclay, France). The tests consist in characterisation of optical performances at all wavelengths and in all three modes (imaging, spectroscopy and coronagraphy), using a test bench (or Ground Support Equipment - GSE) that has been developed for this purpose. The GSE comprises a helium cooled cryostat for the instrument itself, a proto-IR focal plane module (with JPL sensor chip and CEA electronics and housing), a warm telescope simulator that delivers a JWST-like beam, and computers and software for running automatic test procedures. It is designed to allow a large set of performance verifications, such as high-resolution PSF measurements, characterisation of coronagraphs, response to monochromatic line or resolving power of the spectroscopic mode, some of them being unique along the test program of the instrument. After a short description of the test equipment, this paper focuses on the tests results. A full assessment of performances is given. When applicable, performances are cross checked with requirements. Imaging mode and coronagraphy had already been validated on optically representative models along the MIRIM development plan, especially with the Engineering and Test Model (ETM) of MIRIM, early 2008. The FM test campaign allowed us to confirm that the flight model behaves as expected in these two modes. We also tested for the first time, and validated, the low-resolution spectroscopy mode.
Morphological and Functional Remodeling of Vascular Endothelium in Cardiovascular Diseases

The vascular endothelium plays a vital role during embryogenesis and aging and is a cell monolayer that lines the blood vessels. The immune system recognizes the endothelium as its own. Therefore, an abnormality of the endothelium exposes the tissues to the immune system and provokes inflammation and vascular diseases such as atherosclerosis. Its secretory role allows it to release vasoconstrictors and vasorelaxants as well as cardio-modulatory factors that maintain the proper functioning of the circulatory system. The sealing of the monolayer provided by adhesion molecules plays an important role in cardiovascular physiology and pathology.
Sea clutter: Scattering, the K distribution and radar performance

Sea Clutter: Scattering, the K Distribution and Radar Performance, 2nd Edition gives an authoritative account of our current understanding of radar sea clutter. Topics covered include the characteristics of radar sea clutter, modelling radar scattering by the ocean surface, statistical models of sea clutter, the simulation of clutter and other random processes, detection of small targets in sea clutter, imaging ocean surface features, radar detection performance calculations, CFAR detection, and the specification and measurement of radar performance. The calculation of the performance of practical radar systems is presented in sufficient detail for the reader to be able to tackle related problems with confidence. In this second edition the contents have been fully updated and reorganised to give better access to the different types of material in the book. Extensive new material has been added on the Doppler characteristics of sea clutter and detection processing; bistatic sea clutter measurements; electromagnetic scattering theory of littoral sea clutter and bistatic sea clutter; the use of models for predicting radar performance; and use of the K distribution in other fields.
AMS cross-section measurement for the 28 Si(d, α ) 26 Al reaction near the Coulomb barrier

Understanding the production of 26 Al is important in nuclear physics, astrophysics (stellar nucleosynthesis), earth sciences and other ﬁelds. In previous years, we attempted to measure the 28 Si(d, α ) 26 Al reaction cross section at low energies. AMS (Accelerator Mass Spectrometry) at the LEMA (Laboratorio Nacional de Espectrometrometría de Masas con Aceleradores) facility at IFUNAM (Instituto de Física, Universidad Nacional Autónoma de México) was used to measure the concentration of the produced 26 Al in a mixture of Al/Si targets after irradiation with a deuteron beam. Those measurements showed that many improvements had to be made to our protocols in order to reach our goal. In this paper, the continuation of those studies is reported. We take advantage of the recently acquired expertise in the radio-chemistry process to separate aluminum from silicon. Deuteron beams with energies between 3.4 and 4.8 MeV were used to irradiate 5 × 5 × 0.3 mm 3 silicon slabs. Considering that the Coulomb barrier for touching spheres is around 4.7 MeV, our experiment explores an energy interval near the barrier, on the lower energy side. Here reaction cross sections are much larger than those expected at lower energies, toward the Gamow window, an energy range appropriate to develop and test the project’s strategy before tackling the lower energies (most relevant for astrophysics) where the cross sections drop exponentially.
Compositional Inhomogeneity of InGaN Grown on Sapphire and Bulk GaN Substrates by Metalorganic Chemical Vapor Deposition

The compositional inhomogeneity of the InGaN layers in GaN/InGaN/GaN double-hetero (DH) and InGaN/GaN single-hetero (SH) structures grown by metalorganic chemical vapor deposition (MOCVD) on sapphire (0001) and bulk GaN was investigated by means of cathodoluminescence (CL) and energy dispersive X-ray (EDX) spectroscopy. Dotlike CL image of the band edge emission from InGaN was observed. The bright spots were found to have higher indium content compared to that on the outside of the spots. The compositional inhomogeneity increased and the density of the spot decreased with increasing film thickness. Hexagonal hillocks, which had higher indium content and emitted stronger CL, were observed on the surface of the SH structure. Compositional inhomogeneity of homoepitaxial InGaN on bulk GaN substrate was much less compared to that of InGaN on sapphire revealing that dislocation plays a key role in producing an inhomogeneity. A possible mechanism that explains these phenomena is proposed.
A New Variational Model with Dual Level Set Functions for Selective Segmentation

In this paper we present a selective segmentation model using a dual level set variational formulation. Our variational model aims to segment all objects with one level set function (global) and the selected object, which is the closest to the geo- metric constraints (markers), with another level set (local). It is a combination of edge detection, markers distance function and active contour without edges. Experimental results show that our model is more robust than previous work. AMS subject classifications: 62H35, 65N22, 65N55, 74G65, 74G75
PLEKHA4 Is a Prognostic Biomarker and Correlated with Immune Infiltrates in Glioma

Objective Gliomas are the most common and life-threatening intracranial tumors. Immune infiltration of the tumor microenvironment significantly affects tumor prognosis in glioma. Recently, PLEKHA4 was reported to be upregulated in melanoma and closely associated with tumor genesis and development, but its role in glioma is poorly understood. Our aim was to investigate the expression, functional role, and prognostic value of PLEKHA4 in glioma. Methods The expression levels of PLEKHA4 in 33 types of cancer in the TCGA (The Cancer Genome Atlas) database were collected via the UCSC Xena browser. The clinical samples of glioma patients were downloaded from the TCGA database. Immunohistochemistry was used to verify PLEKHA4 expression in tumor tissues. We assessed the influence of PLEKHA4 on survival of glioma patients by survival module and GEPIA. Then, we downloaded datasets of glioma from TCGA and investigated the correlations between the clinical characteristics and PLEKHA4 expression using logistic regression. Moreover, we used TIMER to explore the collection of PLEKHA4 expression and immune infiltration level in glioma and to analyze cumulative survival in glioma. Gene Set Enrichment Analysis (GSEA) was performed using the TCGA dataset. Results PLEKHA4 transcript levels were significantly upregulated in multiple cancer types, including gliomas. Moreover, immunohistochemical analysis verified that PLEKHA4 was overexpressed in gliomas compare to the corresponding normal tissues. Univariable survival and multivariate cox analysis show that increased PLEKHA4 expression significantly correlated with age, tumor grade, IDH mutation status, and 1p/19q codel status, and higher PLEKHA4 had shorter OS, DSS, and PFI. Specifically, PLEKHA4 expression level had significant positive correlations with infiltrating levels of B cell, CD4+ T cells, CD8+ T cells, macrophages, neutrophils, and DCs in glioma, and upregulation of PLEKHA4 expression was significantly related to immune cell biomarkers and immune checkpoint expression in glioma. In addition, several GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) items associated with immune response, JAK STAT signal pathway, and cell cycle were significantly enriched in the high PLEKHA4 expression phenotype pathway. Conclusions Our findings proposed that PLEKHA4 was an independent prognostic biomarker and correlated with immune infiltrates in glioma, and targeting PLEKHA4 might improve immunotherapy in glioma. Of course, these findings also need basic experiments and further clinical trials to confirm in the future.