Publications by authors named "Nowak U"

Article Synopsis
  • Proximity effects in thin ferromagnetic films enable unique adjustments in magnetic properties when they are in contact, influencing their magnetic interactions at the interface.
  • By studying combinations of low-rare-earth ferromagnets and 3d transition metals, researchers can achieve room-temperature magnetism, especially in materials like europium monoxide (EuO) without altering their core properties.
  • Hard X-ray photoelectron spectroscopy techniques reveal that the thickness of the EuO layer significantly impacts its magnetic coupling, demonstrating that this effect is a short-range phenomenon that enhances magnetic order, particularly in lower dimensions, making it valuable for spin-based technologies.
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The exchange bias phenomenon, inherent in exchange-coupled ferromagnetic and antiferromagnetic systems, has intrigued researchers for decades. Van der Waals materials, with their layered structures, offer an ideal platform for exploring exchange bias. However, effectively manipulating exchange bias in van der Waals heterostructures remains challenging.

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Recent research suggests that cognitive deficits in individuals with psychotic disorders could be overestimated because poor cognitive test performance is partly attributable to non-cognitive factors. To further test this, we included non-hospitalized individuals with psychotic disorders (PSY, = 38), individuals with attenuated psychotic symptoms ( = 40), individuals with obsessive-compulsive disorders ( = 39), and healthy controls ( = 38). Relevant cognitive domains were assessed using the MATRICS Consensus Cognitive Battery.

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Two-dimensional van der Waals (vdW) heterostructures are an attractive platform for studying exchange bias due to their defect-free and atomically flat interfaces. Chromium thiophosphate (CrPS), an antiferromagnetic material, possesses uncompensated magnetic spins in a single layer, rendering it a promising candidate for exploring exchange bias phenomena. Recent findings have highlighted that naturally oxidized vdW ferromagnetic FeGeTe exhibits exchange bias, attributed to the antiferromagnetic coupling of its ultrathin surface oxide layer (O-FGT) with the underlying unoxidized FeGeTe.

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Owing to their high magnon frequencies, antiferromagnets are key materials for future high-speed spintronics. Picosecond switching of antiferromagnetic spin systems has been viewed a milestone for decades and pursued only by using ultrafast external perturbations. Here, we show that picosecond spin switching occurs spontaneously due to thermal fluctuations in the antiferromagnetic orthoferrite SmErFeO.

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Magnetic skyrmions, topologically-stabilized spin textures that emerge in magnetic systems, have garnered considerable interest due to a variety of electromagnetic responses that are governed by the topology. The topology that creates a microscopic gyrotropic force also causes detrimental effects, such as the skyrmion Hall effect, which is a well-studied phenomenon highlighting the influence of topology on the deterministic dynamics and drift motion. Furthermore, the gyrotropic force is anticipated to have a substantial impact on stochastic diffusive motion; however, the predicted repercussions have yet to be demonstrated, even qualitatively.

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Psychotic experiences have been associated with distortions in affective functioning, including aberrancies in affect dynamics. However, it remains unclear whether the two principal symptom dimensions of psychosis, namely paranoid ideation and hallucination spectrum experiences, are differently associated with affect dynamics, and whether associations hold after statistically controlling for depressive symptoms. We investigate this by using a novel statistical approach, the hierarchical Ornstein-Uhlenbeck (OU) process model.

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Many malignancies are driven by mutations within the gene for fibroblast growth factor receptor 1 (FGFR1). Previously, we have shown that signal transduction from the FOP2-FGFR1 fusion protein in acute myeloid leukemia KG1 cells is responsible for a low level of expression of the vitamin D receptor gene. In this paper, we address whether other fibroblast growth factor receptors regulate the vitamin D receptor (VDR) gene.

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The transfer and control of angular momentum is a key aspect for spintronic applications. Only recently, it was shown that it is possible to transfer angular momentum from the spin system to the lattice on ultrashort timescales. To contribute to the understanding of angular momentum transfer between spin and lattice degrees of freedom we present a scheme to calculate fully relativistic spin-lattice coupling parameters from first principles.

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Affective disturbances in psychosis are well-documented but our understanding of their phenotypic nature in everyday life remains limited. Filling this gap could advance mechanistic models of the affective pathway to psychosis and pave the ground for new research avenues. Therefore, this study focused on temporal affect dynamics in psychosis, i.

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We explore the dynamics of skyrmions with various topological charges induced by a temperature gradient in an ultra-thin insulating magnetic film. Combining atomistic spin simulations and analytical calculations we find a topology-dependent skyrmion Seebeck effect: while skyrmions and antiskyrmions move to the hot regime, a topologically trivial localized spin structure moves to the cold regime. We further reveal the emergence of a skyrmion Nernst effect, i.

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Magnetic phenomena are ubiquitous in nature and indispensable for modern science and technology, but it is notoriously difficult to change the magnetic order of a material in a rapid way. However, if a thin nickel film is subjected to ultrashort laser pulses, it loses its magnetic order almost completely within femtosecond timescales. This phenomenon is widespread and offers opportunities for rapid information processing or ultrafast spintronics at frequencies approaching those of light.

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Emotion evaluations are assumed to play a crucial role in the emotion regulation process. We tested a postulate from our framework of emotion dysregulation (Nowak, U., Wittkamp, M.

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Background: Ovarian cancer (OC) is one of the most lethal cancers in women. The active form of vitamin D, 1,25-dihydroxyvitamin D (1,25D, calcitriol) has anticancer activity in several cancers, including ovarian cancer, but the required pharmacological doses may cause hypercalcemia. We hypothesized that newly developed, low calcemic, vitamin D analogs (an1,25Ds) may be used as anticancer agents instead of calcitriol in ovarian cancer cells.

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Affective functioning is compromised in people who develop persecutory delusions, but the specifics of these affective disturbances remain unclear. To better understand the precise nature of affective disturbances in this group, it could prove helpful to focus not only on average or momentary affect intensities but also on the dynamic properties of affect, that is, the patterns and regularities with which affect fluctuates over time. This study used experience-sampling in a community sample with varying levels of paranoid ideation ( = 144) to capture different aspects of temporal affect dynamics in the two affective dimensions of valence and arousal.

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Background: Difficulties in the ability to adapt beliefs in the face of new information are associated with psychosis and its central symptom - paranoia. As cognitive processes and psychotic symptoms are both known to be sensitive to stress, the present study investigated the exact associations between stress, adapting of beliefs [reversal learning (RL), bias against disconfirmatory evidence (BADE), and jumping to conclusions (JTC)] and paranoia. We hypothesized that paranoia would increase under stress and that difficulties in adapting of beliefs would mediate or moderate the link between stress and paranoia.

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Dysregulated emotion plays an important role for mental health problems. To elucidate the underlying mechanisms, researchers have focused on the domains of strategy-based emotion regulation, psychophysiological self-regulation, emotion evaluations, and resulting emotion dynamics. So far, these four domains have been looked at in relative isolation from each other, and their reciprocal influences and interactive effects have seldom been considered.

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Magnetic textures are often treated as quasiparticles following Thiele's equation of motion. We demonstrate via spin model simulations of the current-driven and Brownian motion of ferromagnetic skyrmions that the existing theory based on Thiele's equation is insufficient to describe the dynamics of skyrmions at finite temperatures. We propose an extended equation of motion that goes beyond Thiele's equation by taking into account the coupling of the skyrmion to the magnonic heat bath leading to an additional dissipative term that is linear in temperature.

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Equilibrium properties and localized magnon excitations are investigated in topologically distinct skyrmionic textures. The observed shape of the structures and their orientation on the lattice is explained based on their vorticities and the symmetry of the crystal. The transformation between different textures and their annihilation as a function of magnetic field is understood based on the energy differences between them.

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Ultrafast demagnetization of rare-earth metals is distinct from that of 3d ferromagnets, as rare-earth magnetism is dominated by localized 4f electrons that cannot be directly excited by an optical laser pulse. Their demagnetization must involve excitation of magnons, driven either through exchange coupling between the 5d6s-itinerant and 4f-localized electrons or by coupling of 4f spins to lattice excitations. Here, we disentangle the ultrafast dynamics of 5d6s and 4f magnetic moments in terbium metal by time-resolved photoemission spectroscopy.

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(1) : Vitamin D receptor (VDR) is present in multiple types of blood cells, and its ligand, 1,25-dihydroxyvitamin D (1,25D), is important for the proper functioning of the immune system. Activity of VDR is higher in hematopoietic stem and progenitor cells than in fully differentiated blood cells of mice and humans. In some human acute myeloid leukemia (AML) blasts, the expression of the gene is also high.

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For the realm of visual cues, it has been well documented that attention is preferentially oriented toward emotionally relevant cues. Preliminary evidence suggests that emotional cues from other sensory modalities may also steer visual attention toward emotional pictures. However, more research is needed to elucidate the mechanisms that are involved.

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Article Synopsis
  • Magnetic skyrmions can move quickly in thin films using specific torques, showing potential for advanced computing despite limited studies on their thermal effects.
  • Thermally induced motion of skyrmions was explored in a custom low-pinning multilayer material, revealing that temperature greatly influences their dynamics.
  • This motion can enhance probabilistic computing devices, and studying it may provide insights into soft-matter phenomena like thermally induced roughness.
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Background: Cognitive impairment in schizophrenia is highly disabling and remains one of the major therapeutic challenges. Agomelatine (AGO), an agonist at melatonergic MT1/MT2 receptors and antagonist at 5-HT2C receptors, increases dopamine and norepinephrine in the prefrontal cortex and may therefore have the potential of improving neurocognition in patients with schizophrenia.

Methods: Twenty-seven patients with schizophrenia and comorbid depression were treated with AGO in addition to stable doses of antipsychotic drugs.

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Introduction: Cigarette smoking influences response to antidepressant treatment. It accelerates the metabolism of several cytochrome P450 (CYP) subtypes, including CYP1A2, and therefore bears the risk of pharmacokinetic interactions with psychotropic drugs using that pathway. Agomelatine is a substrate of CYP1A2; the association between nicotine use and agomelatine dosage, however, has never been studied before.

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