Miracle-dz/UniFAR-FTUs huggingface dataset:
SEARCHING FOR COMPACT OBJECTS IN SNRs G27.8+0.6 AND G28.8+1.5

We analyzed XMM-Newton observations of two center-filled supernova remnants (SNRs), G27.8+0.6 and G28.8+1.5, to search for pulsars/pulsar wind nebulae (PWNe) and other types of neutron stars (NSs) associated with these remnants. We discovered a PWN candidate within the extent of the centrally peaked radio emission of G27.8+0.6. The X-ray morphology of the PWN candidate and its position with respect to the host SNR suggest that the alleged pulsar might be moving away from the SNR's center with a transverse velocity of around 100–200 km s−1. The majority of the detected X-ray point sources in both fields are classified as main-sequence stars, based on their bright optical counterparts and relatively soft X-ray spectra. The remaining medium–hard and hard sources are most probably either active galactic nuclei or cataclysmic variables, although we cannot completely rule out the possibility that some of these sources are NSs.
Macroeconomics and the Reality of Mixed Frequency Data

Many time series are sampled at different frequencies. When we study co-movements between such series we usually analyze the joint process sampled at a common low frequency. This has consequences in terms of potentially mis-specifying the co-movements and hence the analysis of impulse response functions—a commonly used tool for economic policy analysis. We introduce a class of mixed frequency VAR models that allows us to measure the impact of high frequency data on low frequency and vice versa. Our approach does not rely on latent processes/shocks representations. As a consequence, the mixed frequency VAR is an alternative to commonly used state space models for mixed frequency data. State space models are parameter-driven whereas mixed frequency VAR models are observation-driven models as they are formulated exclusively in terms of observable data and do not involve latent processes as well as shocks and thus avoid the need to formulate measurement equations, filtering, etc. We also propose various parsimonious parameterizations, in part inspired by recent work on MIDAS regressions. We also explicitly characterize the mis-specification of a traditional common low frequency VAR and its implied mis-specified impulse response functions. The class of mixed frequency VAR models can also characterize the timing of information releases for a mixture of sampling frequencies and the real-time updating of predictions caused by the flow of high frequency information. Various estimation procedures for mixed frequency VAR models are also proposed, both classical and Bayesian. Numerical and empirical examples quantify the consequences of ignoring mixed frequency data.
Factors That Affect the COVID-19 Pandemic in Summer 2022 Compared to Summer 2021

The COVID-19 pandemic still goes on. The increasing number of COVID-19 cases has been observed since the start of summer 2022, although this was not in summer 2021. Therefore, we would like to compare factors that were responsible for this trend in five selected countries in the European Union (Greece, Italy, Slovenia, Austria and Germany) using the data from publicly available databases for the analyzed period of weeks 22–30 in 2021 and 2022. The multiple factor analysis was conducted in R, using mean or median score. Our cross-sectional study showed that analyzed countries had similar profiles in 2021 characterized by restrictions and health system policies, as well as B.1. 351, B.1. 1.7, B.1. 617.2 and P.1 variants. Similarly, these countries had similar profiles in 2022, but described by other variables: number of new COVID-19 cases per million, number people fully vaccinated per hundred, number of total boosters administered per hundred and also occurrence of Omicron variant and its sub-lineages. Although the COVID-19 vaccination rate is relatively high in the European Union, during the summer of 2022, the number of COVID-19 cases sharply increased daily, which seems to be connected with the presence of the Omicron variant and its sub-lineages.
QPO emission from moving hot spots on the surface of neutron stars: a model

We present recent results of 3D magnetohydrodynamic simulations of neutron stars with small misalignment angles, as regards the features in light curves produced by regular movements of the hot spots during accretion on to the star. In particular, we show that the variation of position of the hot spot created by the infalling matter, as observed in 3D simulations, can produce high-frequency quasi-periodic oscillations (QPOs) with frequencies associated with the inner zone of the disc. Previously reported simulations show that the usual assumption of a fixed hot spot near the polar region is valid only for misalignment angles Θ relatively large. Otherwise, two phenomena challenge the assumption: one is the presence of Rayleigh-Taylor instabilities at the disc-magnetospheric boundary, which produce tongues of accreting matter that can reach the star almost anywhere between the equator and the polar region; the other one is the motion of the hot spot around the magnetic pole during stable accretion. In this paper, we start by showing that both phenomena are capable of producing short-term oscillations in the light curves. We then use Monte Carlo techniques to produce model light curves based on the features of the movements observed, and we show that the main features of kHz QPOs can be reproduced. Finally, we show the behaviour of the frequencies of the moving spots as the mass accretion rate changes, and propose a mechanism for the production of double QPO peaks.
A proposal for continuous loading of an optical dipole trap with magnetically guided ultra-cold atoms

The capture of a moving atom by a non-dissipative trap, such as an optical dipole trap, requires the removal of the excessive kinetic energy of the atom. In this paper, we develop a mechanism to harvest ultra-cold atoms from a guided atom beam into an optical dipole trap by removing their directed kinetic energy. We propose a continuous loading scheme where this is accomplished via deceleration by a magnetic potential barrier followed by optical pumping to the energetically lowest Zeeman sublevel. We theoretically investigate the application of this scheme to the transfer of ultra-cold chromium atoms from a magnetically guided atom beam into a deep optical dipole trap. We discuss the realization of a suitable magnetic field configuration. Based on numerical simulations of the loading process, we analyse the feasibility and efficiency of our loading scheme.
Nonequilibrium dynamics of vortex arrest in a finite-temperature Bose-Einstein condensate

We perform finite-temperature dynamical simulations of the arrest of a rotating Bose-Einstein condensate by a fixed trap anisotropy, using a Hamiltonian classical-field method. We consider a quasi-two-dimensional condensate containing a single vortex in equilibrium with a rotating thermal cloud. Introducing an elliptical deformation of the trapping potential leads to the loss of angular momentum from the system. We identify the condensate and the complementary thermal component of the nonequilibrium field and compare the evolution of their angular momenta and angular velocities. By varying the trap anisotropy we alter the relative efficiencies of the vortex-cloud and cloud-trap coupling. For strong trap anisotropies the angular momentum of the thermal cloud may be entirely depleted before the vortex begins to decay. For weak trap anisotropies, the thermal cloud exhibits a long-lived steady state in which it rotates at an intermediate angular velocity.
A Dielectric Elastomer Actuator-Driven Vibro-Impact Crawling Robot

Over the last decade, many bio-inspired crawling robots have been proposed by adopting the principle of two-anchor crawling or anisotropic friction-based vibrational crawling. However, these robots are complicated in structure and vulnerable to contamination, which seriously limits their practical application. Therefore, a novel vibro-impact crawling robot driven by a dielectric elastomer actuator (DEA) is proposed in this paper, which attempts to address the limitations of the existing crawling robots. The novelty of the proposed vibro-impact robot lies in the elimination of anchoring mechanisms or tilted bristles in conventional crawling robots, hence reducing the complexity of manufacturing and improving adaptability. A comprehensive experimental approach was adopted to characterize the performance of the robot. First, the dynamic response of the DEA-impact constraint system was characterized in experiments. Second, the performance of the robot was extensively studied and the fundamental mechanisms of the vibro-impact crawling locomotion were analyzed. In addition, effects of several key parameters on the robot’s velocity were investigated. It is demonstrated that our robot can realize bidirectional motion (both forward and backward) by simple tuning of the key control parameters. The robot demonstrates a maximum forward velocity of 21.4 mm/s (equivalent to 0.71 body-length/s), a backward velocity of 16.9 mm/s, and a load carrying capacity of 9.5 g (equivalent to its own weight). The outcomes of this paper can offer guidelines for high-performance crawling robot designs, and have potential applications in industrial pipeline inspections, capsule endoscopes, and disaster rescues.
Galactic Center Minispiral: Interaction Modes of Neutron Stars

Streams of gas and dust in the inner parsec of the Galactic center form a distinct feature known as the Minispiral, which has been studied in radio waveband as well as in the infrared wavebands. A large fraction of the Minispiral gas is ionized by radiation of OB stars present in the Nuclear Star Cluster (NSC). Based on the inferred mass in the innermost parsec ($\sim 10^6$ solar masses), over $\sim 10^3$ -- $10^4$ neutron stars should move in the sphere of gravitational influence of the SMBH. We estimate that a fraction of them propagate through the denser, ionized medium concentrated mainly along the three arms of the Minispiral. Based on the properties of the gaseous medium, we discuss different interaction regimes of magnetised neutron stars passing through this region. Moreover, we sketch expected observational effects of these regimes. The simulation results may be applied to other galactic nuclei hosting NSC, where the expected distribution of the interaction regimes is different across different galaxy types.
Microstructure and Corrosion Properties of Austenitic and Duplex Stainless Steel Dissimilar Joints

In several applications duplex stainless steels should be joint welded to conventional austenitic stainless steels. In this research LDX 2101 lean duplex stainless steel sheets were welded to conventional 304 austenitic stainless steels, using gas tungsten arc welding. For the welded joints three different welding rods were used: ER 308L, ER 309LSi, and ER 2209. For gas shielding two different shielding gases were used: argon and argon +2% nitrogen. It was found that the nitrogen addition to the shielding gas promoted austenite formation in the weld metal. It was also found Schaeffler-diagram modified by Outokumpu showed a very good estimation to the ferrite content and chemical composition of the weld metal. The ferrite content estimated by the Outokumpu-diagram, showed a close correlation to measured ferrite contents, the highest error was 30%. In case of the chemical composition of the weld metal, the Cr- and Ni-contents were estimated with a maximum of 15% error. In terms of the corrosion resistance, the best pitting corrosion resistance was achieved using the 308L welding rod with argon shielding gas, where the weight loss was 1.6% after the 24 hours immersion test.
Vacuum Energy Sequestering: The Framework and Its Cosmological Consequences

Recently we suggested a reformulation of General Relativity which completely sequesters from gravity all of the vacuum energy from a protected matter sector, assumed to contain the Standard Model. Here we elaborate further on the mechanism, presenting additional details of how it cancels all loop corrections and renders all contributions from phase transitions automatically small. We also consider cosmological consequences in more detail and show that the mechanism is consistent with a variety of inationary models that make a universe big and old. We discuss in detail the underlying assumptions behind the dynamics of our proposal, and elaborate on the relationship of the physical interpretation of divergent operators in quantum eld theory and the apparent ‘acausality’ which our mechanism seems to entail, which we argue is completely harmless. It is merely a reection
bHLH010/089 Transcription Factors Control Pollen Wall Development via Specific Transcriptional and Metabolic Networks in Arabidopsis thaliana

The pollen wall is a specialized extracellular cell wall that protects male gametophytes from various environmental stresses and facilitates pollination. Here, we reported that bHLH010 and bHLH089 together are required for the development of the pollen wall by regulating their specific downstream transcriptional and metabolic networks. Both the exine and intine structures of bhlh010 bhlh089 pollen grains were severely defective. Further untargeted metabolomic and transcriptomic analyses revealed that the accumulation of pollen wall morphogenesis-related metabolites, including polysaccharides, glyceryl derivatives, and flavonols, were significantly changed, and the expression of such metabolic enzyme-encoding genes and transporter-encoding genes related to pollen wall morphogenesis was downregulated in bhlh010 bhlh089 mutants. Among these downstream target genes, CSLB03 is a novel target with no biological function being reported yet. We found that bHLH010 interacted with the two E-box sequences at the promoter of CSLB03 and directly activated the expression of CSLB03. The cslb03 mutant alleles showed bhlh010 bhlh089–like pollen developmental defects, with most of the pollen grains exhibiting defective pollen wall structures.
Local and global environmental effects on galaxies and active galactic nuclei

We study the properties of Sloan Digital Sky Survey (SDSS) galaxies with and without active galactic nucleus (AGN) detection as a function of the local and global environment measured via the local density, mass of the galaxy host group (parametrized by the group luminosity) and distance to massive clusters. Our results can be divided into two main subjects: the environments of galaxies and their relation to the assembly of their host haloes, and the environments of AGNs. (i) For the full SDSS sample, we find indications that the local galaxy density is the most efficient parameter to separate galaxy populations, but we also find that galaxies at a fixed local density show some remaining variation in their properties as a function of the distance to the nearest cluster of galaxies (in a range of 0-10 cluster virial radii). These differences seem to become less significant, if the galaxy samples are additionally constrained to be hosted by groups of similar total luminosity. If instead of fixing the local density, the mass of the host group is held fixed at a given value, the fraction of red galaxies also increases as the distance to clusters diminishes, indicating that neither the local density nor the host halo mass contains all the information on the environment. (ii) In AGN host galaxies, the morphology-density relation is much less notable when compared to the behaviour of the full SDSS sample, indicating a lack of sensitivity to the host group mass during the AGN phase, probably due to the higher typical luminosities of the AGN hosts. In order to interpret this result, we analyse control samples constructed using galaxies with no detected AGN activity with matching distributions of redshifts, stellar masses, r-band luminosities, g - r colours, concentrations, local densities, host group luminosities and fractions of central and satellite galaxies; the aim in using the control sample is to detect any correlations between the AGN detection and other AGN host properties that are unrelated to the AGN selection. The control samples also show a similar small dependence on the local density, indicating an influence from the AGN selection, but their colours are slightly bluer compared to the AGN hosts, regardless of the local density. Furthermore, even when the local density is held fixed at intermediate or high values, and the distance to the closest cluster of galaxies is allowed to vary, AGN control galaxies away from clusters tend to be bluer than the AGN hosts. However, AGN in bright, low-concentration hosts (i.e. discy morphologies) are bluer than galaxies in the control sample, connecting the presence of discs to AGN activity even under a controlled comparison between active and inactive galaxies.
Evaluation of a Required Vertical Point-of-Care Ultrasound Curriculum for Undergraduate Medical Students

Introduction Point-of-care ultrasound training beginning in undergraduate medical education reinforces anatomy and physical examination skills and enhances clinical care. Implementation in an overcrowded curriculum requires strategic planning to overcome barriers including lack of faculty and equipment. Using Kern’s six-step model as a framework, our study question was whether a longitudinal point-of-care ultrasound curriculum threaded through four years of medical school and using a novel combination of evidence-based strategies was feasible, acceptable, and resulted in students achieving ultrasound competencies by graduation. Materials and methods From 2016 to 2020, a required, vertical point-of-care ultrasound curriculum was created across all four undergraduate medical education class years, spearheaded by a single ultrasound fellowship-trained emergency physician with support from two basic anatomy faculty. We utilized strategies including handheld ultrasound devices, near-peer teaching, flipped classroom with virtual learning modules, staggered station rotations, and gamification to optimize student-instructor ratios and faculty time. Surveys and timed objective structured clinical assessments evaluated the curriculum. Results Students from the class of 2022 (n=99, 100% of class) participated in all curricular elements. Senior students answered more survey knowledge questions correctly when compared to pretest questions answered by first- and second-year students. Among 84 students who completed the survey, 75 (89%) rated their ultrasound curriculum as superior or above average. Objective structured clinical examination scores recorded for 53 students (54% of the class) demonstrated students correctly identified a median of 11-18 structures (interquartile range: 9.5-13) using point-of-care ultrasound. Conclusion Evidence-based strategies allowed faculty to develop a four-year required ultrasound curriculum that was highly acceptable by students and improved their knowledge and skills at graduation. At low cost and with few faculty, this program has been sustained for over six years.
Preoperative planning using virtual reality for percutaneous transseptal valve-in-valve transcatheter mitral valve replacement: a case report

Abstract Background Virtual reality (VR) technology has been implemented as a pre-procedural planning tool for cardiovascular interventions to enable detailed evaluation of patient anatomy from different vantage points. Here, we employed a VR platform to preoperatively plan for percutaneous valve-in-valve transcatheter mitral replacement (ViV-TMVR) in a prohibitive surgical candidate. Case summary An 85-year-old male with a history of two prior sternotomies for bioprosthetic aortic valve (AV) and mitral valve (MV) 31 mm Medtronic Mosaic bioprosthesis presented with severe mitral regurgitation from a degenerative bioprosthetic MV. The patient was deemed a prohibitive surgical candidate for a third sternotomy and instead was recommended a percutaneous transseptal ViV-TMVR. An electrocardiogram-gated chest computed tomography (CT) provided a neo-left-ventricular outflow tract (neo-LVOT) of 1.89 cm2. This CT was reconstructed to create a 360° VR (360VR) model. A 29 mm SAPIEN three bioprosthetic valve, selected based on the already implanted MV, was placed inside the bioprosthetic MV and analysed in VR at different angles to ensure it would not obstruct the LVOT. The neo-LVOT measured in VR was 3.02 cm2, which would allow for sufficient blood flow without significant obstruction from the new SAPIEN three bioprosthetic valve. The patient tolerated the procedure well. Discussion This case demonstrates the utility of VR as a pre-procedural planning tool for interventional cardiology procedures. Preoperative planning in VR alleviated concerns regarding obstruction of the neo-LVOT and helped confirm safe implantation by clearly showing the three-dimensional spatial relationship between the implants and surrounding patient anatomy.
A Characterisation of Context-Sensitive Languages by Consensus Games

We propose a game for recognising formal languages, in which two players with imperfect information need to coordinate on a common decision, given private input information. The players have a joint objec- tive to avoid an inadmissible decision, in spite of the uncertainty induced by the input. We show that this model of consensus acceptor games characterises context-sensitive languages, and conversely, that winning strategies in such games can be described by context-sensitive languages. This im- plies that it is undecidable whether a consensus game admits a winning strategy, and, even if so, it is PSPACE-hard to execute one. On the pos- itive side, we show that whenever a winning strategy exists, there exists one that can be implemented by a linear bounded automaton.