Observation of Mermin-Wagner behavior in LaFeO3/SrTiO3 superlattices.

Two-dimensional magnetic materials can exhibit new magnetic properties due to the enhanced spin fluctuations that arise in reduced dimension. However, the suppression of the long-range magnetic order in two dimensions due to long-wavelength spin fluctuations, as suggested by the Mermin-Wagner theorem, has been questioned for finite-size laboratory samples. Here we study the magnetic properties of a dimensional crossover in superlattices composed of the antiferromagnetic LaFeO3 and SrTiO3 that, thanks to their large lateral size, allowed examination using a sensitive magnetic probe - muon spin rotation spectroscopy. We show that the iron electronic moments in superlattices with 3 and 2 monolayers of LaFeO3 exhibit a static antiferromagnetic order. In contrast, in the superlattices with single LaFeO3 monolayer, the moments do not order and fluctuate to the lowest measured temperature as expected from the Mermin-Wagner theorem. Our work shows how dimensionality can be used to tune the magnetic properties of ultrathin films.

Comparative study of SPI success factors in global and in-house environment for large-scale software companies.

Background: Software process improvement (SPI) is an indispensable phenomenon in the evolution of a software development company that adopts global software development (GSD) or in-house development. Several software development companies do not only adhere to in-house development but also go for the GSD paradigm. Both development approaches are of paramount significance because of their respective advantages. Many studies have been conducted to find the SPI success factors in the case of companies that opt for in-house development. Still, less attention has been paid to the SPI success factors in the case of the GSD environment for large-scale software companies. Factors that contribute to the SPI success of small as well as medium-sized companies have been identified, but large-scale companies have still been overlooked. The research aims to identify the success factors of SPI for both development approaches (GSD and in-house) in the case of large-scale software companies. Methods: Two systematic literature reviews have been performed. An industrial survey has been conducted to detect additional SPI success factors for both development environments. In the subsequent step, a comparison has been made to find similar SPI success factors in both development environments. Lastly, another industrial survey is conducted to compare the common SPI success factors of GSD and in-house software development, in the case of large-scale companies, to divulge which SPI success factor carries more value in which development environment. For this reason, parametric (Pearson correlation) and non-parametric (Kendall's Tau correlation and the Spearman correlation) tests have been performed. Results: The 17 common SPI factors have been identified. The pinpointed common success factors expedite and contribute to SPI in both environments in the case of large-scale companies.

Deep Learning-Based Classification of Chest Diseases Using X-rays, CT Scans, and Cough Sound Images.

Chest disease refers to a variety of lung disorders, including lung cancer (LC), COVID-19, pneumonia (PNEU), tuberculosis (TB), and numerous other respiratory disorders. The symptoms (i.e., fever, cough, sore throat, etc.) of these chest diseases are similar, which might mislead radiologists and health experts when classifying chest diseases. Chest X-rays (CXR), cough sounds, and computed tomography (CT) scans are utilized by researchers and doctors to identify chest diseases such as LC, COVID-19, PNEU, and TB. The objective of the work is to identify nine different types of chest diseases, including COVID-19, edema (EDE), LC, PNEU, pneumothorax (PNEUTH), normal, atelectasis (ATE), and consolidation lung (COL). Therefore, we designed a novel deep learning (DL)-based chest disease detection network (DCDD_Net) that uses a CXR, CT scans, and cough sound images for the identification of nine different types of chest diseases. The scalogram method is used to convert the cough sounds into an image. Before training the proposed DCDD_Net model, the borderline (BL) SMOTE is applied to balance the CXR, CT scans, and cough sound images of nine chest diseases. The proposed DCDD_Net model is trained and evaluated on 20 publicly available benchmark chest disease datasets of CXR, CT scan, and cough sound images. The classification performance of the DCDD_Net is compared with four baseline models, i.e., InceptionResNet-V2, EfficientNet-B0, DenseNet-201, and Xception, as well as state-of-the-art (SOTA) classifiers. The DCDD_Net achieved an accuracy of 96.67%, a precision of 96.82%, a recall of 95.76%, an F1-score of 95.61%, and an area under the curve (AUC) of 99.43%. The results reveal that DCDD_Net outperformed the other four baseline models in terms of many performance evaluation metrics. Thus, the proposed DCDD_Net model can provide significant assistance to radiologists and medical experts. Additionally, the proposed model was also shown to be resilient by statistical evaluations of the datasets using McNemar and ANOVA tests.

Obesity and Aging.

The obesity epidemic in aging populations poses significant public health concerns for greater morbidity and mortality risk. Age-related increased adiposity is multifactorial and often associated with reduced lean body mass. The criteria used to define obesity by body mass index in younger adults may not appropriately reflect age-related body composition changes. No consensus has been reached on the definition of sarcopenic obesity in older adults. Lifestyle interventions are generally recommended as initial therapy; however, these approaches have limitations in older adults. Similar benefits in older compared with younger adults are reported with pharmacotherapy, however, large randomized clinical trials in geriatric populations are lacking.

Analyzing the Impact of Active Attack on the Performance of the AMCTD Protocol in Underwater Wireless Sensor Networks.

The exponentially growing concern of cyber-attacks on extremely dense underwater sensor networks (UWSNs) and the evolution of UWSNs digital threat landscape has brought novel research challenges and issues. Primarily, varied protocol evaluation under advanced persistent threats is now becoming indispensable yet very challenging. This research implements an active attack in the Adaptive Mobility of Courier Nodes in Threshold-optimized Depth-based Routing (AMCTD) protocol. A variety of attacker nodes were employed in diverse scenarios to thoroughly assess the performance of AMCTD protocol. The protocol was exhaustively evaluated both with and without active attacks with benchmark evaluation metrics such as end-to-end delay, throughput, transmission loss, number of active nodes and energy tax. The preliminary research findings show that active attack drastically lowers the AMCTD protocol's performance (i.e., active attack reduces the number of active nodes by up to 10%, reduces throughput by up to 6%, increases transmission loss by 7%, raises energy tax by 25%, and increases end-to-end delay by 20%).

Precision Measurement of the Lamb Shift in Muonium.

We report a new measurement of the n=2 Lamb shift in Muonium. Our result of 1047.2(2.3)_{stat}(1.1)_{syst} MHz comprises an order of magnitude improvement upon the previous best measurement. This value matches the theoretical calculation within 1 standard deviation allowing us to set limits on Lorentz and CPT violation in the muonic sector, as well as on new physics coupled to muons and electrons which could provide an explanation of the muon g-2 anomaly.

Testosterone Replacement Therapy: A Narrative Review with a Focus on New Oral Formulations.

Male hypogonadism affects 10-30% of the male population and is often under-recognized and under-treated. Different replacement formulations exist, each with specific benefits and limitations. These replacements include gels, patches and short- and long-acting injectables. JATENZO® (oral testosterone undecanoate; Clarus Therapeutics Inc., Northbrook, IL, US) is the first oral formulation of testosterone approved by the US Food and Drug Administration. TLANDO® (oral testosterone undecanoate; Lipocine Inc., Salt Lake City, UT, US), another oral testosterone formulation, has also recently been approved by the US Food and Drug Administration. Based on unique chemistry using a self-emulsifying drug delivery system and lymphatic absorption, JATENZO and TLANDO address some of the limitations of other dosing routes while providing a safe option without evidence of liver dysfunction. This review discusses various testosterone treatment options, focusing on the role and pharmacokinetics of the new oral formulations.

Unveiling unconventional magnetism at the surface of Sr2RuO4.

Materials with strongly correlated electrons often exhibit interesting physical properties. An example of these materials is the layered oxide perovskite Sr2RuO4, which has been intensively investigated due to its unusual properties. Whilst the debate on the symmetry of the superconducting state in Sr2RuO4 is still ongoing, a deeper understanding of the Sr2RuO4 normal state appears crucial as this is the background in which electron pairing occurs. Here, by using low-energy muon spin spectroscopy we discover the existence of surface magnetism in Sr2RuO4 in its normal state. We detect static weak dipolar fields yet manifesting at an onset temperature higher than 50 K. We ascribe this unconventional magnetism to orbital loop currents forming at the reconstructed Sr2RuO4 surface. Our observations set a reference for the discovery of the same magnetic phase in other materials and unveil an electronic ordering mechanism that can influence electron pairing with broken time reversal symmetry.

Intense beam of metastable Muonium.

Precision spectroscopy of the Muonium Lamb shift and fine structure requires a robust source of 2S Muonium. To date, the beam-foil technique is the only demonstrated method for creating such a beam in vacuum. Previous experiments using this technique were statistics limited, and new measurements would benefit tremendously from the efficient 2S production at a low energy muon ( < 20  keV) facility. Such a source of abundant low energy µ + has only become available in recent years, e.g. at the Low-Energy Muon beamline at the Paul Scherrer Institute. Using this source, we report on the successful creation of an intense, directed beam of metastable Muonium. We find that even though the theoretical Muonium fraction is maximal in the low energy range of 2-5 keV, scattering by the foil and transport characteristics of the beamline favor slightly higher µ + energies of 7-10 keV. We estimate that an event detection rate of a few events per second for a future Lamb shift measurement is feasible, enabling an increase in precision by two orders of magnitude over previous determinations.

Muon implantation experiments in films: Obtaining depth-resolved information.

Implanted positive muons with low energies (in the range 1-30 keV) are extremely useful local probes in the study of thin films and multi-layer structures. The average muon stopping depth, typically in the order of tens of nanometers, is a function of the muon implantation energy and of the density of the material, but the stopping range extends over a broad region, which is also in the order of tens of nanometers. Therefore, an adequate simulation procedure is required in order to extract the depth dependence of the experimental parameters. Here, we present a method to extract depth-resolved information from the implantation energy dependence of the experimental parameters in a low-energy muon spin spectroscopy experiment. The method and corresponding results are exemplified for a semiconductor film, Cu(In,Ga)Se2, covered with a thin layer of Al2O3, but can be applied to any heterostructure studied with low-energy muons. It is shown that if an effect is present in the experimental data, this method is an important tool to identify its location and depth extent.

BAMSI: a multi-cloud service for scalable distributed filtering of massive genome data.

BACKGROUND: The advent of next-generation sequencing (NGS) has made whole-genome sequencing of cohorts of individuals a reality. Primary datasets of raw or aligned reads of this sort can get very large. For scientific questions where curated called variants are not sufficient, the sheer size of the datasets makes analysis prohibitively expensive. In order to make re-analysis of such data feasible without the need to have access to a large-scale computing facility, we have developed a highly scalable, storage-agnostic framework, an associated API and an easy-to-use web user interface to execute custom filters on large genomic datasets. RESULTS: We present BAMSI, a Software as-a Service (SaaS) solution for filtering of the 1000 Genomes phase 3 set of aligned reads, with the possibility of extension and customization to other sets of files. Unique to our solution is the capability of simultaneously utilizing many different mirrors of the data to increase the speed of the analysis. In particular, if the data is available in private or public clouds - an increasingly common scenario for both academic and commercial cloud providers - our framework allows for seamless deployment of filtering workers close to data. We show results indicating that such a setup improves the horizontal scalability of the system, and present a possible use case of the framework by performing an analysis of structural variation in the 1000 Genomes data set. CONCLUSIONS: BAMSI constitutes a framework for efficient filtering of large genomic data sets that is flexible in the use of compute as well as storage resources. The data resulting from the filter is assumed to be greatly reduced in size, and can easily be downloaded or routed into e.g. a Hadoop cluster for subsequent interactive analysis using Hive, Spark or similar tools. In this respect, our framework also suggests a general model for making very large datasets of high scientific value more accessible by offering the possibility for organizations to share the cost of hosting data on hot storage, without compromising the scalability of downstream analysis.

Room-temperature helimagnetism in FeGe thin films.

Chiral magnets are promising materials for the realisation of high-density and low-power spintronic memory devices. For these future applications, a key requirement is the synthesis of appropriate materials in the form of thin films ordering well above room temperature. Driven by the Dzyaloshinskii-Moriya interaction, the cubic compound FeGe exhibits helimagnetism with a relatively high transition temperature of 278 K in bulk crystals. We demonstrate that this temperature can be enhanced significantly in thin films. Using x-ray scattering and ferromagnetic resonance techniques, we provide unambiguous experimental evidence for long-wavelength helimagnetic order at room temperature and magnetic properties similar to the bulk material. We obtain α intr = 0.0036 ± 0.0003 at 310 K for the intrinsic damping parameter. We probe the dynamics of the system by means of muon-spin rotation, indicating that the ground state is reached via a freezing out of slow dynamics. Our work paves the way towards the fabrication of thin films of chiral magnets that host certain spin whirls, so-called skyrmions, at room temperature and potentially offer integrability into modern electronics.

Intrinsic Ferromagnetism in the Diluted Magnetic Semiconductor Co:TiO_{2}.

Here we present a study of magnetism in Co_{0.05}Ti_{0.95}O_{2-δ} anatase films grown by pulsed laser deposition under a variety of oxygen partial pressures and deposition rates. Energy-dispersive spectrometry and transmission electron microscopy analyses indicate that a high deposition rate leads to a homogeneous microstructure, while a very low rate or postannealing results in cobalt clustering. Depth resolved low-energy muon spin rotation experiments show that films grown at a low oxygen partial pressure (≈10^{-6} torr) with a uniform structure are fully magnetic, indicating intrinsic ferromagnetism. First principles calculations identify the beneficial role of low oxygen partial pressure in the realization of uniform carrier-mediated ferromagnetism. This work demonstrates that Co:TiO_{2} is an intrinsic diluted magnetic semiconductor.

The phase diagram of electron-doped La(2-x)Ce(x)CuO(4-δ).

Superconductivity is a striking example of a quantum phenomenon in which electrons move coherently over macroscopic distances without scattering. The high-temperature superconducting oxides (cuprates) are the most studied class of superconductors, composed of two-dimensional CuO2 planes separated by other layers that control the electron concentration in the planes. A key unresolved issue in cuprates is the relationship between superconductivity and magnetism. Here we report a sharp phase boundary of static three-dimensional magnetic order in the electron-doped superconductor La(2-x)Ce(x)CuO(4-δ), where small changes in doping or depth from the surface switch the material from superconducting to magnetic. Using low-energy spin-polarized muons, we find that static magnetism disappears close to where superconductivity begins and well below the doping level at which dramatic changes in the transport properties are reported. These results indicate a higher degree of symmetry between the electron and hole-doped cuprates than previously thought.

Direct spectroscopic observation of a shallow hydrogenlike donor state in insulating SrTiO3.

We present a direct spectroscopic observation of a shallow hydrogenlike muonium state in SrTiO(3) which confirms the theoretical prediction that interstitial hydrogen may act as a shallow donor in this material. The formation of this muonium state is temperature dependent and appears below ∼ 70K. From the temperature dependence we estimate an activation energy of ∼ 50 meV in the bulk and ∼ 23 meV near the free surface. The field and directional dependence of the muonium precession frequencies further supports the shallow impurity state with a rare example of a fully anisotropic hyperfine tensor. From these measurements we determine the strength of the hyperfine interaction and propose that the muon occupies an interstitial site near the face of the oxygen octahedron in SrTiO(3). The observed shallow donor state provides new insight for tailoring the electronic and optical properties of SrTiO(3)-based oxide interface systems.

Controlling the near-surface superfluid density in underdoped YBa2Cu3O(6+x) by photo-illumination.

The interaction with light weakens the superconducting ground state in classical superconductors. The situation in cuprate superconductors is more complicated: illumination increases the charge carrier density, a photo-induced effect that persists below room temperature. Furthermore, systematic investigations in underdoped YBa2Cu3O(6+x) (YBCO) have shown an enhanced critical temperature Tc. Until now, studies of photo-persistent conductivity (PPC) have been limited to investigations of structural and transport properties, as well as the onset of superconductivity. Here we show how changes in the magnetic screening profile of YBCO in the Meissner state due to PPC can be determined on a nanometer scale utilizing low-energy muons. The data obtained reveal a strongly increased superfluid density within the first few tens of nanometers from the sample surface. Our findings suggest a non-trivial modification of the near-surface band structure and give direct evidence that the superfluid density of YBCO can be controlled by light illumination.

Photo-induced persistent inversion of germanium in a 200-nm-deep surface region.

The controlled manipulation of the charge carrier concentration in nanometer thin layers is the basis of current semiconductor technology and of fundamental importance for device applications. Here we show that it is possible to induce a persistent inversion from n- to p-type in a 200-nm-thick surface layer of a germanium wafer by illumination with white and blue light. We induce the inversion with a half-life of ~12 hours at a temperature of 220 K which disappears above 280 K. The photo-induced inversion is absent for a sample with a 20-nm-thick gold capping layer providing a Schottky barrier at the interface. This indicates that charge accumulation at the surface is essential to explain the observed inversion. The contactless change of carrier concentration is potentially interesting for device applications in opto-electronics where the gate electrode and gate oxide could be replaced by the semiconductor surface.

Nanoscale layering of antiferromagnetic and superconducting phases in Rb(2)Fe(4)Se(5) single crystals.

We studied phase separation in the single-crystalline antiferromagnetic superconductor Rb(2)Fe(4)Se(5) (RFS) using a combination of scattering-type scanning near-field optical microscopy and low-energy muon spin rotation (LE-µSR). We demonstrate that the antiferromagnetic and superconducting phases segregate into nanometer-thick layers perpendicular to the iron-selenide planes, while the characteristic in-plane size of the metallic domains reaches 10 µm. By means of LE-µSR we further show that in a 40-nm thick surface layer the ordered antiferromagnetic moment is drastically reduced, while the volume fraction of the paramagnetic phase is significantly enhanced over its bulk value. Self-organization into a quasiregular heterostructure indicates an intimate connection between the modulated superconducting and antiferromagnetic phases.

Muonium emission into vacuum from mesoporous thin films at cryogenic temperatures.

We report on muonium (Mu) emission into vacuum following µ(+) implantation in mesoporous thin SiO(2) films. We obtain a yield of Mu into vacuum of (38±4)% at 250 K and (20±4)% at 100 K for 5 keV µ(+) implantation energy. From the implantation energy dependence of the Mu vacuum yield we determine the Mu diffusion constants in these films: D(Mu)(250 K)=(1.6±0.1)×10(-4) cm(2)/s and D(Mu)(100 K)=(4.2±0.5)×10(-5) cm(2)/s. Describing the diffusion process as quantum mechanical tunneling from pore to pore, we reproduce the measured temperature dependence ∼T(3/2) of the diffusion constant. We extract a potential barrier of (-0.3±0.1) eV which is consistent with our computed Mu work function in SiO(2) of [-0.3,-0.9] eV. The high Mu vacuum yield, even at low temperatures, represents an important step toward next generation Mu spectroscopy experiments.

Nature of weak magnetism in SrTiO3/LaAlO3 multilayers.

We report the observation of weak magnetism in superlattices of LaAlO(3)/SrTiO(3) using ß-detected nuclear magnetic resonance. The spin lattice relaxation rate of ^{8}Li in superlattices with a spacer layers of 8 and 6 unit cells of LaAlO(3) exhibits a strong peak near ~35 K, whereas no such peak is observed in a superlattice with spacer layer thickness of 3 unit cells. We attribute the observed temperature dependence to slowing down of weakly coupled electronic moments at the LaAlO(3)/SrTiO(3) interface. These results show that the magnetism at the interface depends strongly on the thickness of the spacer layer, and that a minimal thickness of ~4-6 unit cells is required for the appearance of magnetism. A simple model is used to determine that the observed relaxation is due to small fluctuating moments (~0.002µ(B)) in the two samples with a larger LaAlO(3) spacer thickness.