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Surface Acoustic Waves (SAW) are one of the possible solutions to target the challenges faced by modern spintronic devices. The stress carried by the SAW can decrease the current required to achieve magnetic switching or domain wall movement by spin transfer torque. Although the last decade has produced very relevant results in this field, it is still important to study the effects of a SAW on the basic unit of many spintronic devices, a ferromagnetic nanostrip. In this work, we perform a complete set of measurements and simulations to characterize the magnetization process of a Ni nanostrip under the influence of a SAW. We find that the SAW increases the mobility and the depinning ability of the magnetic domain walls and consequently, promotes a sharper approach to saturation and substantially decreases coercivity. We have also found other two interesting effects. When the SAW has sufficient energy, is able to trigger irreversible transitions even before switching the direction of the external magnetic field. Additionally, we have found that the magnetization process depends on the direction of the travelling SAW.

(1) Background: We propose that cfDNA levels may serve as a valuable biomarker for monitoring the progress of liver transplant recipients, reflecting the quality of the donated organ, and predicting patient prognosis and survival. Thus, we analyzed the relationship between total cfDNA levels during the first 48 h post-transplantation, ischemia–reperfusion injury, and patient outcomes. (2) Methods: cfDNA quantification was applied to 115 liver transplant patients using real-time quantitative PCR at the time of transplantation (during reperfusion) and throughout the first month post-transplantation. (3) Results: Significantly higher early cfDNA levels were observed in patients who suffered liver damage or post-transplantation complications during the first month. High cfDNA levels were also associated with prolonged ICU stays and reduced survival. Kaplan–Meier analysis revealed a significantly lower survival rate in patients with elevated cfDNA. CRP levels were elevated and significantly correlated with cfDNA values. Regarding organ preservation prior to transplantation, prolonged cold and warm ischemia times were significantly associated with high cfDNA levels in the early hours post-transplantation. (4) Conclusions: Elevated cfDNA levels in the early hours following liver transplantation are associated with poorer patient outcomes. Therefore, determining total cfDNA levels post-transplantation may be a valuable tool for patient management and early intervention.

Background/Objectives: Parapneumonic pleural effusion (PPE) secondary to community-acquired pneumonia is the most common cause of pediatric pleural effusion. This study aimed to evaluate the pleural fluid characteristics of pediatric patients with PPE and to compare biomarkers between infants (1–12 months) and children (1–14 years). Methods: Fifty-four pediatric patients (14 infants and 40 children) with PPE were included. Pleural fluid samples were analyzed for white blood cell (WBC) count, glucose, total protein, lactate dehydrogenase (LDH), adenosine deaminase (ADA), and pH levels. Differences between age groups and correlations between age and pleural fluid biomarkers were assessed. Results: Most pediatric PPE cases exhibited biochemical characteristics consistent with pleural exudate: WBC > 1000 cells/µL, total protein > 3 g/dL, LDH > 200 U/L. Infants showed a predominance of mononuclear WBC, while children exhibited a predominance of polymorphonuclear WBC. Glucose levels were higher, and total protein levels were lower in infants compared to children. Age was positively correlated with polymorphonuclear WBC percentage (rho = 0.509, p < 0.001) and protein levels (rho = 0.622, p < 0.001), whereas glucose levels were negatively correlated with age (rho = −0.274, p = 0.043). Conclusions: Age-specific differences in pleural fluid biomarkers were observed in pediatric patients with PPE, suggesting a more robust and acute inflammatory response in children compared to infants. These findings underscore the importance of considering age-related variations in the inflammatory response when diagnosing and managing PPE in pediatric populations.

The snow-line is the distance from a protostar at which a particular volatile gas condenses; images of the protostar V883 Ori suggest that the water snow-line migrated outwards during a protostellar outburst, with implications for our understanding of the formation of planetary systems such as our own. Direct imaging of a protostar snow-line The snow-line in a protoplanetary disk is the distance from the protostar at which a particular volatile gas condenses. Of particular importance in disk evolution is the snow-line for water, because water-ice determines the efficiency of dust and planetesimal coagulation and the formation of comets, ice giants and the cores of gas giants. Lucas Cieza et al . report long-baseline observations of the disk around V883 Ori, a protostar of 1.3 solar masses that is undergoing an accretion outburst. The data provide the first direct image of the water snow-line of a protoplanetary disk and suggest that it migrated outwards during a protostellar outburst, with implications for our understanding of the formation of planetary systems such as our own. A snow-line is the region of a protoplanetary disk at which a major volatile, such as water or carbon monoxide, reaches its condensation temperature. Snow-lines play a crucial role in disk evolution by promoting the rapid growth of ice-covered grains 1 , 2 , 3 , 4 , 5 , 6 . Signatures of the carbon monoxide snow-line (at temperatures of around 20 kelvin) have recently been imaged in the disks surrounding the pre-main-sequence stars TW Hydra 7 , 8 , 9 and HD163296 (refs 3 , 10 ), at distances of about 30 astronomical units ( au ) from the star. But the water snow-line of a protoplanetary disk (at temperatures of more than 100 kelvin) has not hitherto been seen, as it generally lies very close to the star (less than 5 au away for solar-type stars 11 ). Water-ice is important because it regulates the efficiency of dust and planetesimal coagulation 5 , and the formation of comets, ice giants and the cores of gas giants 12 . Here we report images at 0.03-arcsec resolution (12  au ) of the protoplanetary disk around V883 Ori, a protostar of 1.3 solar masses that is undergoing an outburst in luminosity arising from a temporary increase in the accretion rate 13 . We find an intensity break corresponding to an abrupt change in the optical depth at about 42  au , where the elevated disk temperature approaches the condensation point of water, from which we conclude that the outburst has moved the water snow-line. The spectral behaviour across the snow-line confirms recent model predictions 14 : dust fragmentation and the inhibition of grain growth at higher temperatures results in soaring grain number densities and optical depths. As most planetary systems are expected to experience outbursts caused by accretion during their formation 15 , 16 , our results imply that highly dynamical water snow-lines must be considered when developing models of disk evolution and planet formation.

In this work we show that Surface Acoustic Waves (SAW) can induce a very large asymmetry in the magnetoresistance loop of an adjacent ferromagnetic nanostrip, making it look as if it had exchange bias. The Surface Acoustic Wave induces a DC voltage in the ferromagnetic nanostrip. For measurements at constant current, this DC voltage makes the AMR loop asymmetric. In a series of different electrical experiments, we disentangle two different contributions to the induced DC voltage. One of them is independent on the external magnetic field and it is likely due to the acoustoelectric effect. A second contribution depends on the external magnetic field and it is a rectified voltage induced in the piezoelectric substrate as a response to the magnetization dynamics in the magnetostrictive nanostrip. The large asymmetry in the magnetoresistance loop reported in this work is a manifestation of an effective transfer of energy from the SAW to the magnetization dynamics, a mechanism that has been very recently appointed as a possible mean to harvest energy from a heat source.

Nanofabrication has allowed the development of new concepts such as magnetic logic and race-track memory, both of which are based on the displacement of magnetic domain walls on magnetic nanostripes. One of the issues that has to be solved before devices can meet the market demands is the stochastic behaviour of the domain wall movement in magnetic nanostripes. Here we show that the stochastic nature of the domain wall motion in permalloy nanostripes can be suppressed at very low fields (0.6–2.7 Oe). We also find different field regimes for this stochastic motion that match well with the domain wall propagation modes. The highest pinning probability is found around the precessional mode and, interestingly, it does not depend on the external field in this regime. These results constitute an experimental evidence of the intrinsic nature of the stochastic pinning of domain walls in soft magnetic nanostripes. The propagation of magnetic domain walls in nanowires offers promise as the basis of future memory storage technologies. Muñoz and Prieto show that the random pinning of domain walls to structural defects in the nanowires can be suppressed at low fields, thus improving the reliability of the transmission of the domain walls substantially.

Classical novae are runaway thermonuclear burning events on the surfaces of accreting white dwarfs in close binary star systems, sometimes appearing as new naked-eye sources in the night sky 1 . The standard model of novae predicts that their optical luminosity derives from energy released near the hot white dwarf, which is reprocessed through the ejected material 2 – 5 . Recent studies using the Fermi Large Area Telescope have shown that many classical novae are accompanied by gigaelectronvolt γ-ray emission 6 , 7 . This emission likely originates from strong shocks, providing new insights into the properties of nova outflows and allowing them to be used as laboratories for the study of the unknown efficiency of particle acceleration in shocks. Here, we report γ-ray and optical observations of the Milky Way nova ASASSN-16ma, which is among the brightest novae ever detected in γ-rays. The γ-ray and optical light curves show a remarkable correlation, implying that the majority of the optical light comes from reprocessed emission from shocks rather than the white dwarf 8 . The ratio of γ-ray to optical flux in ASASSN-16ma directly constrains the acceleration efficiency of non-thermal particles to be around 0.005, favouring hadronic models for the γ-ray emission 9 . The need to accelerate particles up to energies exceeding 100 gigaelectronvolts provides compelling evidence for magnetic field amplification in the shocks. A tight correlation between gamma rays and optical emission in nova ASASSN-16ma indicates that the optical light comes from reprocessed emission from shocks in the ejecta, rather than an energy release near the hot white dwarf, as in the standard model.

We probe the evolution of globular clusters that could form in giant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that the large and dense enough gas clouds assemble naturally in current hierarchical models of galaxy formation. These clouds are enriched with heavy elements from earlier stars and could produce star clusters in a similar way to nearby molecular clouds. The masses and sizes of the model clusters are in excellent agreement with the observations of young massive clusters. Do these model clusters evolve into globular clusters that we see in our and external galaxies? In order to study their dynamical evolution, we calculate the orbits of model clusters using the outputs of the cosmological simulation of a Milky Way-sized galaxy. We find that at present the orbits are isotropic in the inner 50 kpc of the Galaxy and preferentially radial at larger distances. All clusters located outside 10 kpc from the center formed in the now-disrupted satellite galaxies. The spatial distribution of model clusters is spheroidal, with a power-law density profile consistent with observations. The combination of two-body scattering, tidal shocks, and stellar evolution results in the evolution of the cluster mass function from an initial power law to the observed log-normal distribution.

This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS Stripe 82, a 300 deg2 area along the celestial equator. This data release is comprised of all transient sources brighter than r 22.5 mag with no history of variability prior to 2004. Dedicated spectroscopic observations were performed on a subset of 889 transients, as well as spectra for thousands of transient host galaxies using the SDSS-III BOSS spectrographs. Photometric classifications are provided for the candidates with good multi-color light curves that were not observed spectroscopically, using host galaxy redshift information when available. From these observations, 4607 transients are either spectroscopically confirmed, or likely to be, supernovae, making this the largest sample of supernova candidates ever compiled. We present a new method for SN host-galaxy identification and derive host-galaxy properties including stellar masses, star formation rates, and the average stellar population ages from our SDSS multi-band photometry. We derive SALT2 distance moduli for a total of 1364 SN Ia with spectroscopic redshifts as well as photometric redshifts for a further 624 purely photometric SN Ia candidates. Using the spectroscopically confirmed subset of the three-year SDSS-II SN Ia sample and assuming a flat ΛCDM cosmology, we determine M = 0.315 0.093 (statistical error only) and detect a non-zero cosmological constant at 5.7 .