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Conductivities are key material parameters that govern various types of transport (electronic charge, spin, heat and so on) driven by thermodynamic forces. Magnons, the elementary excitations of the magnetic order, flow under the gradient of a magnon chemical potential1–3in proportion to a magnon (spin) conductivity. The magnetic insulator yttrium iron garnet is the material of choice for efficient magnon spin transport. Here we report a giant magnon conductivity in thin yttrium iron garnet films with thicknesses down to 3.7 nm when the number of occupied two-dimensional subbands is reduced from a large number to a few, which corresponds to a transition from three-dimensional to two-dimensional magnon transport. We extract a two-dimensional magnon spin conductivity around 1 S at room temperature, comparable to the (electronic) conductivity of the high-mobility two-dimensional electron gas in GaAs quantum wells at millikelvin temperatures4. Such high conductivities offer opportunities to develop low-dissipation magnon-based spintronic devices.

There is a clinical need for therapeutics for COVID-19 patients with acute hypoxemic respiratory failure whose 60-day mortality remains at 30-50%. Aviptadil, a lung-protective neuropeptide, and remdesivir, a nucleotide prodrug of an adenosine analog, were compared with placebo among patients with COVID-19 acute hypoxaemic respiratory failure.

The transport of spin information has been studied in various materials, such as metals, semiconductors and graphene. In these materials, spin is transported by the diffusion of conduction electrons. Here we study the diffusion and relaxation of spin in a magnetic insulator, where the large bandgap prohibits the motion of electrons. Spin can still be transported, however, through the diffusion of non-equilibrium magnons, the quanta of spin-wave excitations in magnetically ordered materials. Here we show experimentally that these magnons can be excited and detected fully electrically in a linear response, and can transport spin angular momentum through the magnetic insulator yttrium iron garnet (YIG) over distances as large as 40 μm. We identify two transport regimes: the diffusion-limited regime for distances shorter than the magnon spin diffusion length, and the relaxation-limited regime for larger distances. With a model similar to the diffusion–relaxation model for electron spin transport in (semi)conducting materials, we extract the magnon spin diffusion length λ = 9.4 ± 0.6 μm in a thin 200 nm YIG film at room temperature.

Improving the quality and efficiency of surgical techniques, reducing technical errors in the operating suite, and ultimately improving patient safety and outcomes through education are common goals in all surgical specialties. Current surgical simulation programs represent an effort to enhance and optimize the training experience, to overcome the training limitations of a mandated 80-hour work week, and have the overall goal of providing a well-balanced resident education in a society with a decreasing level of tolerance for medical errors.

Alterntive to photolithography process for fabrication of 2D arrays of magnetic dots is proposed from a very simple, fast and low cost technique, of laser ablation. Magnetic films with different compositions, structures (NiFe, CoZr, FeN monolayers and [Co/Cu]nmultilayers) and thickness (from 100 to 300 nm) have been submitted at the focalisation point of an ionized argon laser (3W CW maximum power) to a lateral movement produced by a motorized X-Y translation stage. Tracks of partial or total ablation down to the substrate can be realized with well defined width from 3 to 100 microns, depending on the laser beam defocusing and power and on the sample velocity. The possibility of different patterns corresponding to stripes, bars and square 2D arrays with dinerent shape factor is described with size decreasing from millimeter to micron scale. It is shown that laser sputtering can induce strong changes in both static and dynamical magnetic properties of the films as discussed from the magnetization processes of domain wall at low frequency and the complex permeability in the microwave range.

Les objectifs du présent travail sont de deux ordres : d'abord obtenir le rapport de MRG, ΔR/R, le plus élevé dans des multicouches Co/Cu élaborées à partir du procédé inhabituel de pulvérisation par diode radiofréquence (RF). En second, analyser les corrélations entre la MRG d'une part et les textures et rugosités interfaciales déduites des diffractions X aux petits et grands angles et de la microscopie à force atomique (MFA) d'autre part. A cet effet, nous avons cherché à induire différentes structures interfaciales en modifiant les paramètres de pulvérisation (pression du gaz pulvérisant PAr) ce qui, par ailleurs, a permis de définir les conditions optimales de dépôt pour l'obtention d'une MRG élevée. L'influence de l'épaisseur tCodu film Co a été étudiée pour une épaisseur du film de Cu = 9Å correspondant au premier maximum de la dépendance oscillatoire avec tCudu rapport de MRG. De ces résultats, nous concluons que le paramètre pertinent est la rugosité interfaciale qui induit un effet important à la fois sur la MRG et sur la résistivité des super-réseaux. Un changement de pente de Rs-1en fonction de t2Coest attribué à une augmentation de l'effet de rugosité quand tCodécroît de l'échelle mésoscopique (tCo> 25Å) vers l'échelle nanoscopique (tCo< 25Å).

This article reviews complications associated with the endovascular management of intracranial aneurysms, focusing on risk factors, avoidance, recognition, and management. Such complications can be devastating. Both neurologic and nonneurologic complications can occur. Several patient and procedure related parameters can increase the incidence of complications. Reduction of complication rates can be achieved by careful patient selection, meticulous planning and preparation for the procedure, anticipating potential complications, and preparing for their management. Tracking outcomes and a robust case conference can further enhance outcomes. Education of the care team and a collaborative environment can foster greater focus on avoidance of complications.

Purpose To review the current literature for the nonoperative and operative treatment for adult spinal deformity.Recent Findings With more than 11 million baby boomers joining the population of over 60 years of age in the United States, the incidence of lumbar deformity is greatly increasing. Recent literature suggests that a lack of evidence exists to support the effectiveness of nonoperative treatment for adult scoliosis. In regards to operative treatment, current literature reports a varying range of improved clinical outcomes, curve correction, and complication rates. The extension of fusion to S1 compared with L5 and lower thoracic levels compared with L1 remains a highly controversial topic among literature.Summary Most adult deformity patients never seek nonoperative or operative treatment. Of the few that seek treatment, many can benefit from nonoperative treatment. However, in selected patients who have failed nonoperative treatment and who are candidates for surgical intervention, the literature reflects positive outcomes related to surgical intervention as compared with nonoperative treatment despite varying associated ranges in morbidity and mortality rates. If nonoperative therapy fails in addressing a patient's complaints, then an appropriate surgical procedure that relieves neural compression, corrects excessive sagittal or coronal imbalance, and results in a solidly fused, pain-free spine is warranted.

Bone graft substitutes have been used routinely for spine fusion for decades, yet clinical evidence establishing comparative data remains sparse. With recent scrutiny paid to the outcomes, complications, and costs associated with osteobiologics, a need to improve available data guiding efficacious use exists. We review the currently available clinical literature, studying the outcomes of various biologics in posterolateral lumbar spine fusion, and establish the need for a multicenter, independent osteobiologics registry.

A longitudinal magneto-optical Kerr effect and magnetization-induced second-harmonic generation (MSHG) of light (at 2omega) have been measured in a SiO2/Fe96Si4/Dy30Fe58Co12/glass exchange-coupled magnetic bilayer system with competitive anisotropies. Theoretical MSHG predictions in this structure that give rise to an effect proportional to magnetization components and that are allowed by an electric dipole mechanism are reported and discussed. The magnitude of the MSHG effect depends on the electric field of the incoming radiation at each interface and on the corresponding incoming (at omega) and outgoing (at 2omega) Fresnel coefficients. It is demonstrated that transverse pp MSHG selectively probes the magnetization of the first SiO2/Fe96Si4 interface, while transverse sp and longitudinal ps MSHG is sensitive, but less selectively, to the Fe96Si4/Dy30Fe58Co12 interface that supports a planar magnetic domain wall. (p and s are the usual parallel and perpendicular polarizations to the plane of incidence.) The contribution to MSHG by gradient magnetization terms is negligible.

In this work, we present a study of the structural, magnetic and magnetotransport properties in magnetic multilayered structures (NiFeCo/Cu) at room temperature. The magnetic (m) and nonmagnetic (nm) layer thickness (tm, tnm) and the composition of the magnetic layer effect on the magnetoresistance (MR) have been investigated experimentally and discussed theoretically in the framework of the Johnson-Camley semiclassical approach, based on the Boltzmann transport equation. The observed MR ratio oscillates for the Cu layer thickness with an average period of 12 Å and decreases from one system to another less rich in Co. The MR peak position depends on the magnetic layer composition. The materials become harder with increasing Co concentration.

Abstract:: The magnetization dynamics is studied on 3D micromagnetic structures and in the aperiodic time regime. Experiments are compared with various micromagnetic simulations. The model system chosen is a vertical Bloch line inside a bubble garnet epitaxial film. It is shown that the Slonczewski equations describe with remarkable accuracy the experimental phenomena, qualitatively and quantitatively. The damping constant derived from the adjustment of all data is distinctly higher than the value derived from ferromagnetic resonance. Models for this discrepancy are discussed.

It has been reported that the severe cerebral edema produced in experimental animals by Clostridium perfringens(Cl p) type D ε toxin can be prevented by prior treatment with its precursor prototoxin due to competitive binding to endothelial cells (ECs) at the blood–brain barrier (BBB). In this study we investigate the effects of the prototoxin on the BBB, without added toxin. The integrity of the BBB was assessed by its ability to prevent leakage of endogenous albumin. ECs at the BBB were studied by immunocytochemistry for any alteration in the endothelial barrier antigen (EBA), a molecular marker for the intact BBB. Immunocytochemistry showed rapid but mild opening of the BBB to endogenous albumin. Light and electron immunocytochemistry showed qualitative and quantitative reduction in EBA immunoreactivity, with a spectrum of changes at time intervals from 1 h to 14 days post-prototoxin injection. Some vessels with ultrastructural changes and widening of the perivascular space retained EBA immunoreactivity. Many vessels showed partial or complete loss of EBA staining with minimal widening of the perivascular space and edema. Recovery of EBA expression was still incomplete at 14 days postinjection. This is the first report to show endothelial cell damage, mild reversible cerebral edema, and alteration in BBB markers following administration of Cl pprototoxin. This model of mild brain edema may be useful for BBB studies.

Neutron waveguiding properties of antiferromagnetically exchange coupled Co/Cu magnetic superlattice are demonstrated. Neutron propagation in this kind of multi-quantum well-type waveguide is spin-dependent. The proposed novel guiding structure exhibits simultaneously electron spin-dependent transport and neutron waveguiding properties. The neutron waveguiding can be another interesting method of analysis of such structures. We applied the multi-quantum well calculation method to these structures.

Rotenone decreases the incidence of hepatocellular carcinoma and lowers rates of hepatocellular proliferation. In an effort to delineate mechanisms involved, the in vivo effect of rotenone on liver mitochondrial metabolism, apoptotic machinery as well as elements of the hepatic signal transduction pathways were investigated. Mitochondria from livers of male B6C3F1 mice fed a standard diet containing 600 ppm rotenone for 7 days were uncoupled or inhibited when succinate or glutamate plus malate were used as the substrate, respectively. These livers also showed a significant increase in apoptosis compared with control livers. Furthermore, rotenone increased the expression of c-myc mRNA to 5-fold of control values within 3 days, an effect which was still observed (3-fold) after 7 days. Levels of p53 mRNA were also increased 3-fold after 1 day, but declined to control levels by 7 days. Rotenone also caused a transient, yet marked increase in liver particulate glyceraldehyde phosphate dehydrogenase (GAPDH) protein expression, while it did not alter the expression of the cytosolic form of the enzyme. Conversely, mRNA of the proto-oncogene H-ras showed a decline of 35% after 3 days of rotenone treatment, and remained diminished for the duration of the experiment. These data suggest that rotenone may act as an anticancer agent by diminishing mitochondrial bioenergetics which prevents basal hepatocyte proliferation and lowers the threshold for liver cells with DNA damage to undergo apoptosis.

The precursor to rat liver mitochondrial aspartate aminotransferase has been expressed in Escherichia coliJM105 using the pKK233-2 expression vector. This mammalian natural precursor has been isolated as a soluble dimeric protein. The amino-terminal sequence and the amino acid composition of the isolated protein correspond to those predicted from the inserted cDNA (Mattingly, J. R., Jr., Rodriguez-Berrocal, F. J., Gordon, J., Iriarte, A., and Martinez-Carrion, M. (1987) Biochem. Biophys. Res. Commun. 149, 859–865). The isolated precursor contains bound pyridoxal phosphate and shows catalytic activity with a specific activity equal to that of the mature form of the enzyme. This precursor can also be processed by mitochondria into a form with the sodium dodecyl sulfate-polyacrylamide gel electrophoresis mobility of mature enzyme. The isolation of this precursor as a stable and catalytically active entity indicates that the presequence peptide does not necessarily interfere with much of the folding and basic structural properties of the mature protein component.

Since amorphous Co"1"0"0"-"xZr"x alloys present ultrasoft properties, higher sensitivity is expected in CoZr/Cu multilayers compared to the Co/Cu system as investigated in the present work from two types (I and II) of hybrid magnetic structures [(F"1/F"2/F"1)Cu]"1"5 where (F"1/F"2/F"1) is a magnetic sandwich corresponding to either [(CoZr/Co/CoZr)]"1"5 (type I) or [(Co/CoZr/Co)Cu]"1"5 (type II) and F"1 is a very thin magnetic layer inserted at the interfaces between the Cu layer and the magnetic F"2-based multilayers. Strong changes in the magnetization hysteresis curve, the indirect exchange coupling J and the magnetoresistive properties are observed with the insertion of a very thin magnetic CoZr (Co) layer at the interfaces between Cu spacer layers and the magnetic Co (CoZr) layer in Co/Cu (CoZr/Cu) multilayers. Insertion of a 2 A thick CoZr layer into interfaces of the Co/Cu type I multilayers induces significant reduction by a factor 5 of J and the magnetoresistance @D R/R. Opposite evolution is observed when a thin Co layer is inserted in CoZr/Cu type II multilayers. The dependences of the magnetic and magnetoresistive characteristics with the insertion are correlated with the interface roughness change as deduced from XRD at low angles.