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The anomalous Nernst effect (ANE), as a three-dimensional thermoelectric effect in ferromagnetic materials, is expected to break through the limitations of the traditional Seebeck effect, thereby improving thermoelectric conversion efficiency. This study reports an anisotropic anomalous Nernst effect in metallic nickel assembled by the alignment of nanowires. It is found that the ANE voltage varies with the angle to the alignment direction of nanowires within the in-plane of metallic nickel. The ANE voltage reaches 530 nV under a longitudinal temperature difference of 23 K when the magnetic field is applied parallel to the alignment direction of nanowires, which is 143% of its value in the vertical direction. This design concept for anisotropic materials may provide a novel path to enhanced thermoelectric efficiency in ANE-based thermoelectric devices. [ABSTRACT FROM AUTHOR]

Antiferromagnetic spin dynamics is the key issue to develop spintronic devices. We adopt ab initio nonadiabatic molecular dynamics with spin–orbit-coupling (SOC) to investigate photoinduced spin dynamics in an antiferromagnetic semiconductor MnPS3 monolayer. Optical doping triggers MnPS3 from Néel antiferromagnetic to ferromagnetic phase at an experimentally achievable electron–hole pair density of 1.11 × 1014 cm−2. This phase transition can be ascribed to the light-induced mid-gap states of S-p orbitals, which lower the electron excitation energy and strengthen the SOC effect between S-p and Mn-d orbitals. The excited S-p electrons first decay to the mid-gap states due to p–p electron–phonon-coupling and then relax to the spin-down Mn-d orbitals via SOC. Such a dramatic relaxation process prolongs the photogenerated carrier lifetime up to 648 fs, providing an explanation for the unusual optoelectronic performance of MnPS3. The reversible switching of magnetic order via optical means gives an important clue for information storage and highly efficient photocatalysts utilizing antiferromagnetic semiconductors. [ABSTRACT FROM AUTHOR]

With the widespread application of EMI filters, a method to improve power density has become a main concern in switch mode power supplies. Many previous works have been done for improving the EMI filtering performance of chokes. This article investigates an integrated choke structure that can minimize the leakage magnetic flux, enlarge the DM inductance, and improve the DM noise suppression performance. Compared to discrete EMI filter inductors, the proposed stacked choke scheme can integrate CM and DM chokes into toroidal cores by applying a combination of different types of toroidal cores. The proposed inductor can exhibit better DC magnetic saturation characteristic. Finite Element Method (FEM) simulations, impedance measurement, insertion loss and conducted EMI noise spectrums (150 kHz–30 MHz) are used to validate the accuracy of the theoretical analysis and the proposed equivalent magnetic reluctance models. [ABSTRACT FROM AUTHOR]

In superconductors, a topological configuration of the superconducting order parameter called a superconducting vortex carries magnetization. Such a magnetic topological object behaves like a minute particle generating a magnetic flux. Since the flux is localized with a nanometer scale, the vortex provides a nano-scale probe for local magnetic fields. Here we show that information of magnetic stripes in insulators can be read out by using vortices in an adjacent superconductor film as a probe. The orientation and width of magnetic micro stripes are both transcribed into resistance change of the superconductor through the modulation of vortex mobility affected by local magnetization. By changing the direction of external magnetic fields, zero-field resistance changes continuously according to the stripe orientation, and its modulation magnitude reaches up to 100%. The width of the stripes can also be estimated from the oscillatory magnetoresistance. Our results demonstrate a new possibility for non-volatile analog memory devices based on topological objects. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), as an emerging environmental pollutant, is potentially harmful to plant growth. Chlorophyll (Chl) is critical in photosynthesis that provides matter and energy for plant growth. How BPA affects the chlorophyll content remains largely unknown. Here, the effects of BPA on Chl synthesis in soybean seedlings were investigated. Exposure to 1.5 mg/L BPA decreased the 5-aminolevulinic acid (ALA) content and increased protoporphyrin IX (Proto IX), magnesium protoporphyrin, and protochlorophyll contents and 5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, uroporphyrinogen III decarboxylase, and protoporphyrinogen oxidase activities. Exposure to 17.2 and 50.0 mg/L BPA exerted the opposite effects on these four intermediates and five enzymes. Following the withdrawal of BPA exposure, the aforementioned parameters gradually recovered, except magnesium protoporphyrin content in exposure to 50.0 mg/L BPA. Our findings revealed that exposure to low-concentration BPA increased the Chl content in soybean seedlings through improving Chl synthesis, especially the conversion from ALA to Proto IX, whereas exposure to high-concentration BPA decreased the Chl content through inhibiting Chl synthesis, especially the conversion from ALA to Proto IX. The dual effects of BPA were largely reversed following the withdrawal of BPA exposure. [ABSTRACT FROM AUTHOR]

Neural tube defects (NTDs) are serious congenital malformations. Excessive maternal homocysteine (Hcy) increases the risk of NTDs, while its mechanism remains elusive. Here we report the role of histone homocysteinylation in neural tube closure (NTC). A total of 39 histone homocysteinylation sites are identified in samples from human embryonic brain tissue using mass spectrometry. Elevated levels of histone KHcy and H3K79Hcy are detected at increased cellular Hcy levels in human fetal brains. Using ChIP-seq and RNA-seq assays, we demonstrate that an increase in H3K79Hcy level down-regulates the expression of selected NTC-related genes including Cecr2, Smarca4, and Dnmt3b. In human NTDs brain tissues, decrease in expression of CECR2, SMARCA4, and DNMT3B is also detected along with high levels of Hcy and H3K79Hcy. Our results suggest that higher levels of Hcy contribute to the onset of NTDs through up-regulation of histone H3K79Hcy, leading to abnormal expressions of selected NTC-related genes. Elevated maternal homocysteine (Hcy) increases the risk for neural tube defects (NTDs) but how this arises is unclear. Here, the authors show that high levels of Hcy on histone H3K79Hcy correlate with NTDs, causing abnormal gene expression (for example Cecr2, Smarca4 and Dnmt3B) linked to neural tube closure. [ABSTRACT FROM AUTHOR]