ac Hall Effect and Photon Drag of Superconducting Condensates.

We suggest a theoretical description of the photogalvanic phenomena arising in superconducting condensates in the field of electromagnetic wave. The ac Hall effect and photon drag are shown to originate from the second-order nonlinear response of superconducting carriers caused by the suppression of their concentration due to the combined influence of the electron-hole asymmetry and charge imbalance generated by the incident electromagnetic wave. Starting from the time-dependent Ginzburg-Landau theory with the complex relaxation constant, we develop a phenomenological description of these phenomena and investigate the resulting behavior of the dc supercurrent and second harmonic induced by microwave radiation incident on a superconductor surface.

Transcriptomic Analysis of DNA Repair Pathways in Human Non-Small Cell Lung Cancer Cells Surviving Multifraction X-Ray Irradiation.

Radioresistant sublines of non-small cell lung cancer cells differing in the p53 status were obtained: A549 (p53 wild type) and H1299 (p53 deficient). The exposure to ionizing radiation was carried out using a standard protocol developed on the basis of empirical clinical experience and consisting in exposure in a dose of 2 Gy once a day, 5 days a week up to total dose of 60 Gy. The cells survived after irradiation demonstrated reduced radiosensitivity, as well as changes in differential gene expression in comparison with parental cells. Some differences in the signaling pathways involved in DNA repair were revealed.

Extremely long-range, high-temperature Josephson coupling across a half-metallic ferromagnet.

The Josephson effect results from the coupling of two superconductors across a spacer such as an insulator, a normal metal or a ferromagnet to yield a phase coherent quantum state. However, in junctions with ferromagnetic spacers, very long-range Josephson effects have remained elusive. Here we demonstrate extremely long-range (micrometric) high-temperature (tens of kelvins) Josephson coupling across the half-metallic manganite La0.7Sr0.3MnO3 combined with the superconducting cuprate YBa2Cu3O7. These planar junctions, in addition to large critical currents, display the hallmarks of Josephson physics, such as critical current oscillations driven by magnetic flux quantization and quantum phase locking effects under microwave excitation (Shapiro steps). The latter display an anomalous doubling of the Josephson frequency predicted by several theories. In addition to its fundamental interest, the marriage between high-temperature, dissipationless quantum coherent transport and full spin polarization brings opportunities for the practical realization of superconducting spintronics, and opens new perspectives for quantum computing.

Inverse Faraday Effect for Superconducting Condensates.

The Cooper pairs in superconducting condensates are shown to acquire a temperature-dependent dc magnetic moment under the effect of the circularly polarized electromagnetic radiation. The mechanisms of this inverse Faraday effect are investigated within the simplest version of the phenomenological dynamic theory for superfluids, namely, the time-dependent Ginzburg-Landau (GL) model. The light-induced magnetic moment is shown to be strongly affected by the nondissipative oscillatory contribution to the superconducting order parameter dynamics, which appears due to the nonzero imaginary part of the GL relaxation time. The relevance of the latter quantity to the Hall effect in the superconducting state allows us to establish the connection between the direct and inverse Faraday phenomena.

Molecular Pathway Activation Markers Are Associated with Efficacy of Trastuzumab Therapy in Metastatic HER2-Positive Breast Cancer Better than Individual Gene Expression Levels.

Increased expression or amplification of HER2 receptor tyrosine kinase gene ERBB2 is well-known and widely used as a prognostic biomarker of breast cancer (BC) response to the targeted treatment with trastuzumab and its analogs. Considering that part of the BC patients overexpressing HER2 does not respond to trastuzumab, clinical trial NCT03521245 was initiated to identify additional gene expression and molecular pathway activation response biomarkers to trastuzumab treatment in HER2-positive BC. Using RNA sequencing gene expression in 23 formalin-fixed, paraffin embedded HER2 positive BC tissue blocks from patients who either responded or not responded to trastuzumab treatment was profiled. Differentially regulated genes and molecular pathways were identified in the groups of trastuzumab responders and non-responders. These results were next compared with the 42 previously published BC trastuzumab responder and non-responder RNA sequencing profiles from the clinical trials NCT00513292 and NCT00353483. No correlation was observed between the response status and the expression levels of ERBB2 gene in the HER2 positive BC samples. Analysis of the differentially expressed genes and molecular pathways in the combined dataset revealed 15/27 commonly up/down regulated genes and 15/25 pathways, respectively. However, only the intersection of molecular pathways upregulated in trastuzumab responders vs non-responders was statistically significantly enriched compared to the random expectation model. A classifier built using the most significantly upregulated molecular pathway - cAMP Pathway Protein Retention - demonstrated the best performance for prediction of the HER2 positive BC response to trastuzumab for both our experimental and previously reported data. This pathway also predicted time to recurrence in the combined dataset with Log-rank p-value 0.041.

Quasiparticle tunnel electroresistance in superconducting junctions.

The term tunnel electroresistance (TER) denotes a fast, non-volatile, reversible resistance switching triggered by voltage pulses in ferroelectric tunnel junctions. It is explained by subtle mechanisms connected to the voltage-induced reversal of the ferroelectric polarization. Here we demonstrate that effects functionally indistinguishable from the TER can be produced in a simpler junction scheme-a direct contact between a metal and an oxide-through a different mechanism: a reversible redox reaction that modifies the oxide's ground-state. This is shown in junctions based on a cuprate superconductor, whose ground-state is sensitive to the oxygen stoichiometry and can be tracked in operando via changes in the conductance spectra. Furthermore, we find that electrochemistry is the governing mechanism even if a ferroelectric is placed between the metal and the oxide. Finally, we extend the concept of electroresistance to the tunnelling of superconducting quasiparticles, for which the switching effects are much stronger than for normal electrons. Besides providing crucial understanding, our results provide a basis for non-volatile Josephson memory devices.

Erratum: Magnetic Moment Manipulation by a Josephson Current [Phys. Rev. Lett. 102, 017001 (2009)].

This corrects the article DOI: 10.1103/PhysRevLett.102.017001.

Theory of Magnetic Domain Phases in Ferromagnetic Superconductors.

Recently discovered superconducting P-doped EuFe_{2}As_{2} compounds reveal the situation when the superconducting critical temperature substantially exceeds the ferromagnetic transition temperature. The main mechanism of the interplay between magnetism and superconductivity occurs to be an electromagnetic one, and a short-period magnetic domain structure was observed just below Curie temperature [V. S. Stolyarov et al., Sci. Adv. 4, eaat1061 (2018)SACDAF2375-254810.1126/sciadv.aat1061]. We elaborate a theory of such a transition and demonstrate how the initial sinusoidal magnetic structure gradually transforms into a solitonlike domain one. Further cooling may trigger a first-order transition from the short-period domain Meissner phase to the self-induced ferromagnetic vortex state, and we calculate the parameters of this transition. The size of the domains in the vortex state is basically the same as in the normal ferromagnet, but with the domain walls which should generate the set of vortices perpendicular to the vortices in the domains.

Fraunhofer patterns in magnetic Josephson junctions with non-uniform magnetic susceptibility.

The development of superconducting memory and logic based on magnetic Josephson junctions relies on an understanding of junction properties and, in particular, the dependence of critical current on external magnetic flux (i.e. Fraunhofer patterns). With the rapid development of Josephson junctions with various forms of inhomogeneous barrier magnetism, Fraunhofer patterns are increasingly complex. In this paper we model Fraunhofer patterns for magnetic Josephson junctions in which the barrier magnetic susceptibility is position- and external-magnetic-field dependent. The model predicts anomalous Fraunhofer patterns in which local minima in the Josephson critical current can be nonzero and non-periodic with external magnetic flux due to an interference effect between magnetised and demagnetised regions.

Temperature Controlled Fulde-Ferrell-Larkin-Ovchinnikov Instability in Superconductor-Ferromagnet Hybrids.

We show that a wide class of layered superconductor-ferromagnet (S/F) hybrids demonstrates the emergence of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase well below the superconducting transition temperature. By decreasing the temperature, one can switch the system from uniform to the FFLO state which is accompanied by the damping of the diamagnetic Meissner response down to zero and also by the sign change in the curvature of the current-velocity dependence. Our estimates show that an additional layer of the normal metal (N) covering the ferromagnet substantially softens the conditions required for the predicted FFLO instability, and for existing S/F/N systems, the temperature of the transition into the FFLO phase can reach several kelvins.

Magnetic Exchange Fields and Domain Wall Superconductivity at an All-Oxide Superconductor-Ferromagnet Insulator Interface.

At a superconductor-ferromagnet (S/F) interface, the F layer can introduce a magnetic exchange field within the S layer, which acts to locally spin split the superconducting density of states. The effect of magnetic exchange fields on superconductivity has been thoroughly explored at S-ferromagnet insulator (S/FI) interfaces for isotropic s-wave S and a thickness that is smaller than the superconducting coherence length. Here we report a magnetic exchange field effect at an all-oxide S/FI interface involving the anisotropic d-wave high temperature superconductor praseodymium cerium copper oxide (PCCO) and the FI praseodymium calcium manganese oxide (PCMO). The magnetic exchange field in PCCO, detected via magnetotransport measurements through the superconducting transition, is localized to the PCCO/PCMO interface with an average magnitude that depends on the presence or absence of magnetic domain walls in PCMO. The results are promising for the development of all-oxide superconducting spintronic devices involving unconventional pairing and high temperature superconductors.

Potentialities of MicroRNA Diagnosis in Patients with Bladder Cancer.

Despite promising vista of the use of microRNA in molecular diagnosis of bladder cancer, there are few data on their expression profiles, which impedes assessment of diagnostic value of these marker molecules. In this study, suppression subtractive hybridization, on-chip hybridization, and high-throughput deep sequencing focused on profiling microRNA and assessing the diagnostic value of revealed marker molecules.

Spontaneous Currents in Superconducting Systems with Strong Spin-Orbit Coupling.

We show that Rashba spin-orbit coupling at the interface between a superconductor and a ferromagnet should produce a spontaneous current in the atomic thickness region near the interface. This current is counterbalanced by the superconducting screening current flowing in the region of the width of the London penetration depth near the interface. Such a current-carrying state creates a magnetic field near the superconductor surface, generates a stray magnetic field outside the sample edges, changes the slope of the temperature dependence of the critical field H_{c3}, and may generate the spontaneous Abrikosov vortices near the interface.

Optical manipulation of single flux quanta.

Magnetic field can penetrate into type II superconductors in the form of Abrikosov vortices, which are magnetic flux tubes surrounded by circulating supercurrents often trapped at defects referred to as pinning sites. Although the average properties of the vortex matter in superconductors can be tuned with magnetic fields, temperature or electric currents, handling of individual Abrikosov vortices remains challenging and has been demonstrated only with sophisticated scanning local probe microscopies. Here we introduce a far-field optical method based on local heating of the superconductor with a focused laser beam to realize a fast and precise manipulation of individual vortices, in the same way as with optical tweezers. This simple approach provides the perfect basis for sculpting the magnetic flux profile in superconducting devices like a vortex lens or a vortex cleaner, without resorting to static pinning or ratchet effects.

Giant Mesoscopic Fluctuations and Long-Range Superconducting Correlations in Superconductor-Ferromagnet Structures.

The fluctuating superconducting correlations emerging in dirty hybrid structures under the conditions of the strong proximity effect are demonstrated to affect the validity range of the widely used formalism of Usadel equations at mesoscopic scales. In superconductor-ferromagnet structures these giant mesoscopic fluctuations originating from the interference effects for the Cooper pair wave function in the presence of the exchange field can be responsible for an anomalously slow decay of superconducting correlations in a ferromagnet even when the noncollinear and spin-orbit effects are negligible. The resulting sample-to-sample fluctuations of the Josephson current in superconductor-ferromagnetic-superconductor junctions and the local density of states in superconductor-ferromagnetic hybrid structures can provide an explanation of the long-range proximity phenomena observed in mesoscopic samples with collinear magnetization.

[Receptor tyrosine kinase KIT may regulate expression of genes involved in spontaneous regression of neuroblastoma].

Hallmark of neuroblastoma is an ability of this malignant tumor to undergo spontaneous regression or differentiation into benign tumor during any stage of the disease, but it is little known about mechanisms of these phenomena. We studied effect of receptor tyrosine kinase receptor KIT on expression of genes, which may be involved in tumor spontaneous regression. Downregulation of KIT expression by RNA interference in SH-SY5Y cells causes suppression of neurotrophin receptor NGFR expression that may promote the loss of sensibility of cells to nerve growth factors, also it causes upregulation of TrkA receptor expression which can stimulate cell differentiation or apoptosis in NGF dependent manner. Furthermore there is an upregulation of genes which stimulate malignant cell detection by immune system, such as genes of major histocompatibility complex HLA class I HLA-B and HLA-C, and interferon-γ receptors IFNGR1 and IFNGR2 genes. Thus KIT can mediate neuroblastoma cell sensibility to neurotrophins and immune system components--two factors directly contributing to spontaneous regression of neuroblastoma.

Direct Evidence of Flexomagnetoelectric Effect Revealed by Single-Molecule Spectroscopy.

We report direct evidence of the electric field induced by a magnetization inhomogeneity in an iron garnet film. This inhomogeneity was created by the nonuniform magnetic fields generated at domain boundaries of a type-I superconductor in the intermediate state. At liquid helium temperatures, Stark shifts of sharp single-molecule zero-phonon lines were used to probe the local electric fields generated by this flexomagnetoelectric effect. The measured electric fields are in accordance with theoretical estimations.

Double Path Interference and Magnetic Oscillations in Cooper Pair Transport through a Single Nanowire.

We show that the critical current of the Josephson junction consisting of superconducting electrodes coupled through a nanowire with two conductive channels can reveal the multiperiodic magnetic oscillations. The multiperiodicity originates from the quantum mechanical interference between the channels affected by both the strong spin-orbit coupling and the Zeeman interaction. This minimal two-channel model is shown to explain the complicated interference phenomena observed recently in Josephson transport through Bi nanowires.

Stimulation of a singlet superconductivity in SFS weak links by spin-exchange scattering of cooper pairs.

Josephson junctions with a ferromagnetic metal weak link reveal a very strong decrease of the critical current compared to a normal metal weak link. We demonstrate that in the ballistic regime the presence of a small region with a non-collinear magnetization near the center of a ferromagnetic weak link restores the critical current inherent to the normal metal. The above effect can be stimulated by additional electrical bias of the magnetic gate which induces a local electron depletion of ferromagnetic barrier. The underlying physics of the effect is the interference phenomena due to the magnetic scattering of the Cooper pair, which reverses its total momentum in the ferromagnet and thus compensates the phase gain before and after the spin-reversed scattering. In contrast with the widely discussed triplet long ranged proximity effect we elucidate a new singlet long ranged proximity effect. This phenomenon opens a way to easily control the properties of SFS junctions and inversely to manipulate the magnetic moment via the Josephson current.

Silencing AML1-ETO gene expression leads to simultaneous activation of both pro-apoptotic and proliferation signaling.

The t(8;21)(q22;q22) rearrangement represents the most common chromosomal translocation in acute myeloid leukemia (AML). It results in a transcript encoding for the fusion protein AML1-ETO (AE) with transcription factor activity. AE is considered to be an attractive target for treating t(8;21) leukemia. However, AE expression alone is insufficient to cause transformation, and thus the potential of such therapy remains unclear. Several genes are deregulated in AML cells, including KIT that encodes a tyrosine kinase receptor. Here, we show that AML cells transduced with short hairpin RNA vector targeting AE mRNAs have a dramatic decrease in growth rate that is caused by induction of apoptosis and deregulation of the cell cycle. A reduction in KIT mRNA levels was also observed in AE-silenced cells, but silencing KIT expression reduced cell growth but did not induce apoptosis. Transcription profiling of cells that escape cell death revealed activation of a number of signaling pathways involved in cell survival and proliferation. In particular, we find that the extracellular signal-regulated kinase 2 (ERK2; also known as mitogen-activated protein kinase 1 (MAPK1)) protein could mediate activation of 23 out of 29 (79%) of these upregulated pathways and thus may be regarded as the key player in establishing the t(8;21)-positive leukemic cells resistant to AE suppression.