Dilute magnetic semiconductor oxides (DMSOs) hold great promise in bridging spintronics with semiconductor electronics, offering the potential for highly compact, high data-processing devices with reduced power consum...
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Dilute magnetic semiconductor oxides (DMSOs) hold great promise in bridging spintronics with semiconductor electronics, offering the potential for highly compact, high data-processing devices with reduced power consumption. Oxygen-deficient HfO2 stands out among DMSOs due to its technologically important characteristics-large dielectric constant (kappa congruent to 25), high refractive index (2.9) and excellent compatibility with CMOS technology. The origin of ferromagnetism in DMSOs, including HfO2, is mainly attributed to oxygen vacancies. Two main strategies have been explored to enhance ferromagnetism in DMSOs: synthesizing low-dimensional nanostructures to increase oxygen vacancies via a high surface-to-volume ratio (i.e. a high specific surface area) and material doping with appropriate magnetic or non-magnetic ions to induce further vacancies within the lattice. The fabrication of doped 1D nanostructures combines both approaches to enhance ferromagnetism in DMSOs. To date, the fabrication of doped single-crystalline HfO2 1D nanostructures has remained elusive due to technical challenges. This work pioneers the fabrication of Ti-doped HfO2 (i.e., Hf1-xTixO2;0.01 <= x <= 0.50) 1D nanostructures with novel magnetic properties by using catalyst-assisted pulsed laser deposition. Increasing the Ti content is found to lead to shorter Hf1-xTixO2 1D nanostructures, while, interestingly, the resulting magnetic properties show enhancement with increased Ti content, with Hf1-xTixO2 (10 at% Ti doping) exhibiting saturation magnetization nearly twice that of undoped HfO2 nanowires. Given the high compatibility of Hf1-xTixO2 with CMOS technology and their critical temperature above room temperature, these novel nanostructures promise new applications in spintronic-CMOS integrated device technology.
C. Carlet [Boolean functions for Cryptography and Coding theory, p. 381] mentions an observation of Dillon, that is, APN functions f on F-2(n) with n greater than 2 must satisfy the condition {f (x) + f (y) + f(z) + f...
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C. Carlet [Boolean functions for Cryptography and Coding theory, p. 381] mentions an observation of Dillon, that is, APN functions f on F-2(n) with n greater than 2 must satisfy the condition {f (x) + f (y) + f(z) + f (x + y + z) | x, y, z is an element of F-2(n)} = F-2(n). We generalize this condition for functions f from F(2)(n )to F(2)(m )as {f(x) + f (y) + f (z) + f (x + y + z) | x, y, z is an element of F-2(n)} = F-2(m) and call it the D-property. We characterize the D-property for APN functions from F-2(n) toF(2)(m) using F-2-linear surjections pi from F-2(m) to F-2(m)1 for m(1) smaller than m, and investigate this condition with respect to nonlinearity and CCZ-equivalence. Then, we give several families of APN functions f from F(2)(n )to F-2(n+1) with n greater than or equal to 5 that satisfy the D-property.
Germanium substitution in the well-known photovoltaic material Cu2ZnSnS4 has been previously shown to improve power conversion efficiencies, but detailed information about the local structure within solid solutions Cu...
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Germanium substitution in the well-known photovoltaic material Cu2ZnSnS4 has been previously shown to improve power conversion efficiencies, but detailed information about the local structure within solid solutions Cu2ZnSn1-xGexS4 has so far been lacking. Given the many ways the metal cations can be distributed, several structural models for the site distribution are possible. In conjunction with powder X-ray diffraction, multinuclear magnetic resonance spectroscopy (Cu-63/65, Zn-67, Ge-73, and Sn-119) was applied to evaluate these models because these nuclei are sensitive to variations in the coordination environments around specific atoms. The Zn-67 NMR spectra indicate that Zn atoms are in lower symmetry environments in Cu2ZnGeS4 than in Cu2ZnSnS4, as their different quadrupole coupling constants suggested. The Ge-73 and Sn-119 NMR spectra show gradual changes in chemical shift, indicating that Ge and Sn atoms are randomly mixed in tetrahedral sites within the entire range of solid solubility. The Cu-63/65 NMR spectra collected at high field (21.1 T) reveal two distinct Cu sites for all members of Cu2ZnSn1-xGexS4, consistent with the structure model in space group I, as also supported by DFT calculations of NMR parameters. Ge substitution increases the experimental band gap from 1.5 eV in Cu2ZnSnS4 to 2.0 eV in Cu2ZnGeS4 because the conduction band minimum is raised to higher energy, as shown by electronic structure calculations.
The angular spirodihydrofurans, i.e., the 2 ' H ,4 ' H -spiro[cyclopentane-1,3 ' -cyclopenta[ b ]furan]-2,4 ' ,5-triones, were produced by the Mn(III)-based oxidation of the aryl -substituted (methylen...
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The angular spirodihydrofurans, i.e., the 2 ' H ,4 ' H -spiro[cyclopentane-1,3 ' -cyclopenta[ b ]furan]-2,4 ' ,5-triones, were produced by the Mn(III)-based oxidation of the aryl -substituted (methylene)bis(3-hydroxycyclopent-2-en-1-one) s. On the other hand, a similar reaction of alkyl -substituted (methylene)bis(3-hydroxycyclopent-2-en-1-one)s did not give the angular or linear spirodihydrofurans, but dispirocyclopropanes, i.e., the 11-alkyldispiro[4.0.4 6 .1 5 ] undecane-1,4,7,10-tetraones. The structure determination of the products and the reaction pathway for the formation of the angular spirodihydrofurans via the dispirocyclopropanes are discussed.
BackgroundAllergic conjunctivitis (AC) affects people's daily life and work, especially the health of children. Although there are few relevant studies, Th17/Treg imbalance plays an important role in AC developmen...
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BackgroundAllergic conjunctivitis (AC) affects people's daily life and work, especially the health of children. Although there are few relevant studies, Th17/Treg imbalance plays an important role in AC development. The aim of this study was to elucidate the effect of TWEAK/Fn14 on AC and Th17/Treg *** induced AC mouse model was utilized to observe the mechanism of TWEAK/Fn14 in vivo. Conjunctivitis was evaluated by hematoxylin-eosin staining, toluidine blue staining and AC clinical score. Flow cytometry was used to measure Th17 and Treg cell ratios. The level of Th17/Treg balance related factors and Nrf2/HO-1 signal was detected by ELISA, WB, qRT-PCR and *** the AC state, disruption of Th17/Treg cell balance, increased TWEAK/Fn14 signaling level and conjunctival inflammation were observed. After TWEAK knockdown, Th17 cell differentiation was inhibited, Treg cell differentiation was promoted, and AC symptoms were alleviated in AC mice. Moreover, TWEAK knockdown caused an enhancement of the Nrf2/HO-1 signaling pathway in the AC models. Treatment with Nrf2 inhibitor reversed these changes induced by TWEAK knockdown. Therefore, TWEAK/Fn14 regulated the Nrf2/HO-1 pathway to affect Th17/Treg cell balance and conjunctivitis in AC mouse *** summary, TWEAK/Fn14 caused Th17/Treg imbalance by inhibiting Nrf2/HO-1 pathway, which might be one potential mechanism of the exacerbation of AC.
p-Type Fe2VAl-based thermoelectrics have been much less investigated compared to their respective n-type counterparts. Thus, it is crucial to identify novel doping strategies to realize enhanced p-type Fe2VAl Heusler ...
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p-Type Fe2VAl-based thermoelectrics have been much less investigated compared to their respective n-type counterparts. Thus, it is crucial to identify novel doping strategies to realize enhanced p-type Fe2VAl Heusler compounds. In the current study, the effect of Mn substitution in Fe2V1-xMnxAl is investigated with respect to temperature-dependent electronic transport as well as temperature- and field-dependent magnetic properties. We find an anomalous and unexpected p-type Seebeck coefficient for nominally n-doped Fe2V1-xMnxAl over an extremely large range of concentrations up to x = 0.6. Using density functional theory (DFT) calculations, this is traced back to distinct modifications of the electronic structure, i.e., localized magnetic defect states (m = 2.43 mu(B)) at the valence and conduction band edges, and a concomitant pinning of the Fermi level within the pseudogap. Furthermore, we were able to further optimize the thermoelectric properties by co-doping Al antisites in off-stoichiometric Fe2V0.9Mn0.1Al1+y, yielding sizeable values of the power factor, PF = 2.2 mW K-2 m(-1) in Fe2V0.9Mn0.1Al1.1 at 350 K, and figure of merit, ZT similar to 0.1 for highly off-stoichiometric Fe2V0.9Mn0.1Al1.5 at T = 500 K. Our work underlines the prospect of engineering Fe2VAl-based Heusler compounds via magnetic doping to realize enhanced p-type thermoelectris and encourages studies involving other types of co-substitution for Mn-substituted Fe2V1-xMnxAl.
The Voltage-Gated Calcium Channel (VGCC) auxiliary subunit Cav alpha 2 delta -1 ( CACNA2D1 ) is the target/receptor of gabapentinoids which are known therapeutics in epilepsy and neuropathic pain. Following damage to ...
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The Voltage-Gated Calcium Channel (VGCC) auxiliary subunit Cav alpha 2 delta -1 ( CACNA2D1 ) is the target/receptor of gabapentinoids which are known therapeutics in epilepsy and neuropathic pain. Following damage to the peripheral sensory nervous system, Cav alpha 2 delta -1 is upregulated in dorsal root ganglion (DRG) neurons in several animal models of chronic neuropathic pain. Gabapentinoids, such as gabapentin and pregabalin, engage with Cav alpha 2 delta -1 via binding an arginine residue (R241) within an RRR motif located at the N-terminus of human Cav alpha 2 delta -1. A novel, next generation gabapentinoid, engineered not to penetrate the brain, was able to generate a strong analgesic response in Chronic Constriction Injury animal model of chronic neuropathic pain and showed binding specificity for Cav alpha 2 delta -1 versus the Cav alpha 2 delta -2 subunit. This novel non-brain penetrant gabapentinoid, binds to R241 and a novel binding site on Cav alpha 2 delta -1, which is located within the VGCC_ alpha 2 domain, identified as a lysine residue within an IKAK amino acid motif (K634). The overall whole cell current amplitudes were diminished by the compound, with these inhibitory effects being diminished in R241A mutant Cav alpha 2 delta -1 subunits. The functional effects occurred at lower concentrations than those needed for inhibition by gabapentin or pregabalin, which apparently bound the Cav alpha 2 delta -1 subunit only on the R241 and not on the K634 residue. Our work sets the stage for the identification and characterisation of novel compounds with therapeutic properties in neuropathic pain and possibly in other disorders and conditions which require engagement of the Cav alpha 2 delta -1 target.
Anti-vascular endothelial growth factor (VEGF) drugs suppress choroidal neovascularisation (CNV), thus improving vision. However, some patients may have a poor response or develop resistance to anti-VEGF drugs. Gerani...
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Anti-vascular endothelial growth factor (VEGF) drugs suppress choroidal neovascularisation (CNV), thus improving vision. However, some patients may have a poor response or develop resistance to anti-VEGF drugs. Geraniin (GE), a polyphenol isolated from an herb called Phyllanthus amarus, possesses anti-angiogenic properties. This study aimed to explore the mechanism of action of GE in CNV. GE was found to activate the angiotensin-converting enzyme 2 (ACE2)/angiotensin 1-7 (Ang-[1-7])/MAS1 proto-oncogene, G protein-coupled receptor (MasR)/interleukin-10 (IL-10) pathway in hypoxic human choroidal endothelial cells (HCECs) in vitro and mouse models of laser-induced CNV in vivo. Activation of the ACE2/Ang-(1-7)/MasR/IL-10 pathway by GE attenuated the proliferative, migratory, and tube-forming abilities of hypoxic HCECs and prevented the development of CNV in mice. Notably, GE did not cause ocular or systemic toxicity in mice with CNV. These findings suggest that GE alleviates CNV by activating the ACE2/Ang-(1-7)/MasR/IL-10 pathway in choroidal endothelial cells (CECs).
A novel synthetic method of 1,1,2,2-tetrafluoro-2-[(1,2,2-trifluoroethenyl)oxy]ethanesulfonyl fluoride, the raw material for perfluorinated polymer electrolyte membranes, was developed from the starting material CF3CF...
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A novel synthetic method of 1,1,2,2-tetrafluoro-2-[(1,2,2-trifluoroethenyl)oxy]ethanesulfonyl fluoride, the raw material for perfluorinated polymer electrolyte membranes, was developed from the starting material CF3CF (COF)O(CF2)2SO2F via the ring-opening reaction of cyclic compound and the cleavage reaction of vinyl sulfonic anhydride using commercially available reagents.
Dimers of anthra[1,2-a]anthracene-1-yl units and its mesityl derivative were synthesized by Ni(0)-mediated coupling of the corresponding chloro derivatives as new biaryls. The X-ray analysis and DFT calculations revea...
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Dimers of anthra[1,2-a]anthracene-1-yl units and its mesityl derivative were synthesized by Ni(0)-mediated coupling of the corresponding chloro derivatives as new biaryls. The X-ray analysis and DFT calculations revealed that two polycyclic aromatic units with nonplanar deformations took a twisted conformation about the single bond as a chiral axis. Enantiomers of the nonsubstituted compound were resolved by chiral HPLC, and the enantiopure samples showed intense Cotton effects at 321 nm in the circular dichroism (CD) spectra and emission bands at 449 nm in the circularly polarized luminescence (CPL) spectra with dissymmetry factor of |g(lum)| 3.6x10(-3). The absolute stereochemistry of this biaryl was determined by the theoretical calculation of CD spectrum by the time-dependent DFT method. The barrier to enantiomerization was determined to be 108 kJ mol(-1) at 298 K. The dynamic process proceeded via a stepwise mechanism involving the helical inversion of each aromatic unit and the rotation about the biaryl axis as analyzed by the DFT calculations.
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