Characteristics Of Mn Research Articles

Manganese-Based Tumor Immunotherapy.

As an essential micronutrient, manganese (Mn) participates in various physiological processes and plays important roles in host immune system, hematopoiesis, endocrine function, and oxidative stress regulation. Mn-based nanoparticles are considered to be biocompatible and show versatile applications in nanomedicine, in particular utilized in tumor immunotherapy in the following ways: 1) acting as a biocompatible nanocarrier to deliver immunotherapeutic agents for tumor immunotherapy; 2) serving as an adjuvant to regulate tumor immune microenvironment and enhance immunotherapy; 3) activating host's immune system through the cGAS-STING pathway to trigger tumor immunotherapy; 4) real-time monitoring tumor immunotherapy effect by magnetic resonance imaging (MRI) since Mn2+ ions are ideal MRI contrast agent which can significantly enhance the T1 -weighted MRI signal after binding to proteins. This comprehensive review focuses on the most recent progress of Mn-based nanoplatforms in tumor immunotherapy. The characteristics of Mn are first discussed to guide the design of Mn-based multifunctional nanoplatforms. Then the biomedical applications of Mn-based nanoplatforms, including immunotherapy alone, immunotherapy-involved multimodal synergistic therapy, and imaging-guided immunotherapy are discussed in detail. Finally, the challenges and future developments of Mn-based tumor immunotherapy are highlighted.

Influence of electrodeposition parameters on the characteristics of Mn–Co coatings on Crofer 22 APU ferritic stainless steel

Manganese–cobalt coatings are promising candidates for solid oxide fuel cell (SOFC) interconnection applications because of their high conductivity and good oxidation resistance. In the present study, manganese and cobalt are electrodeposited on Crofer 22 APU ferritic stainless steel. The effects of current density, pH, sodium gluconate \((\hbox {NaC}_{6}\hbox {H}_{11}\hbox {O}_{7})\) concentration, cobalt sulphate concentration \((\hbox {CoSO}_{4}{\cdot }7\hbox {H}_{2}\hbox {O})\) and deposition duration on the microstructure and cathodic efficiency are characterized by means of scanning electron microscopy, weight gain measurements and energy-dispersive X-ray spectrometry, respectively. Results show that increases in current density and deposition duration lead to decrease in current efficiency and deposition rate. Increasing the pH to 2.5 causes an initial rise of current efficiency and deposition rate, followed by subsequent decline. In addition, the increases in sodium gluconate and cobalt sulphate concentrations in the electrolyte solution result in an increase in current efficiency and deposition rate. Moreover, the results demonstrate that the variations in the current density, pH, sodium gluconate (\(\hbox {NaC}_{6}\hbox {H}_{11}\hbox {O}_{7}\)) concentration, cobalt sulphate concentration (\(\hbox {CoSO}_{4}{\cdot }7\hbox {H}_{2}\hbox {O}\)) and duration have a significant effect on grain size, uniformity and the adherence of the coating.

Optical Properties of Mn-Doped ZnTe Magic Size Nanocrystals.

In this letter we report successful doping of ZnTe magic size nanocrystals (MSNCs) with Mn(2+). Colloidal ZnTe MSNCs are prepared via a hot-injection method and doped with Mn(2+) via cation exchange. The doped MSNCs show an emission band centered at 620 nm with a radiative decay time of 45 μs, characteristic of Mn(2+) in ZnTe. The excitation spectrum of the Mn(2+) emission shows narrow absorption bands corresponding to different sizes of ZnTe MSNCs providing further evidence that the 620 nm emission originates from Mn(2+) incorporated in the ZnTe host, rather than Mn(2+) bound to the surface. The Mn(2+)-doped ZnTe clusters may serve as nuclei for the growth of larger ZnTe quantum dots doped with a single Mn(2+) ion.

Large Amplitude Piezoelectric Properties of KNbO3-based Lead-free Ferroelectric Ceramics

High power piezoelectric characteristics of Mn doped KNbO3 (KN+MnCO3 x wt% x=0∼0.8 wt%, KN-Mnx) ceramics were firstly reported in this paper. Mechanical quality factor, Qm, of KN-Mn x ceramics at small amplitude vibration increased with increasing Mn content and the Qm of KN-Mn0.8 ceramic reached about 820. The maximum vibration velocity, vo-p, about 2.3 m/s was obtained for KN-Mn0.8 with Qm=820. The Qm at large-amplitude vibration for KN-Mn0.8 and Pb(Zr,Ti)O3 [PZT]-based ceramics [N6] decreased with increasing the vo-p. The Qm of KN-Mn0.8 was smaller than that of N6 at the small-amplitude vibration. However, at the large amplitude vibration, vo-p>0.6 m/s, the Qm value of KN-Mn0.8 was larger than that of N6. Therefore, it was clarified that KN-based lead-free piezoelectric ceramics possess superior mechanical stability at large-amplitude vibration. This is very good sign for high power piezoelectric applications.

Characteristics of MnxSi1-xTe Compound Studied by Electron Magnetic Resonance and Other Experiments

The magnetic and other physical characteristics of <TEX>$Mn_xSi_{1-x}Te$</TEX> have been investigated by electron magnetic resonance (EMR), X-ray diffraction (XRD) and other experiments. <TEX>$Mn_xSi_{1-x}Te$</TEX> is found to have corundum structure for manganese contents up to 10% and also to be ferromagnetic for temperatures below 80 K. While ferromagnetic resonance signal coexists with the usual paramagnetic resonance signal, invariance of the g-factor inferred from the electron paramagnetic resonance signals throughout all temperature ranges clearly confirms that the manganese ions are in the electronic 3d5 state. The temperature dependence of EMR line-width is the same as other diluted magnetic semiconductors. From the EMR signals relaxation times <TEX>$T_2$</TEX> and <TEX>$T_1$</TEX> of <TEX>$Mn_xSi_{1-x}Te$</TEX> compounds are estimated to be about <TEX>$4.4{\times}10^{-10}s$</TEX> and <TEX>$9.3{\times}10^{-8}s$</TEX> respectively and are found to vary slightly with temperature or composition change. Exchange narrowing of the EMR line-width becomes dominant for the sample in which the substitution ratio, x = 30%. For one sample, in which x = 0.5%, spin glass-like behavior is indicated by EMR signals for temperatures lower than 60 K. This behavior may authentic for samples within a certain range of x.

Effect of Alkali Ions on the Absorption Characteristics of Mn (III) in Glasses

Absorption characteristics of Mn3+ ion in alkali borate and alkali silicate glasses were investigated. The absorption maximum due to Mn3+ ion was found to shift more towards the longer wavelengths with increasing ionic radii of the alkali ions and the results were discussed in the light of ligand field approach.

Characterization of Mn-Doped in 1−x GaxAsyP1−y Grown By Lpee

ABSTRACTMn-doped In1−x GaxAsyP1−y epilayers lattice matched to InP substrate have been grown by the liquid phase electroepitaxial (LPEE) technique. The variation of growth velocity of the epilayers with current density and the doping characteristics of Mn in the epilayer has been studied. The temperature dependence of the hole concentration and the mobility has been analysed to determine the donor and acceptor densities, thermal activation energy of the level associated with Mn and the dominant scattering mechanisms that limit the hole mobility. The photoluminescence spectra of the doped epilayers are examined at 10K as a function of the excitation level.

Bacterial contribution to manganese oxidation in a deep coastal sediment

The characteristics of Mn(II) removal from sediment porewater and the potential role of manganese-oxidizing bacteria in this process were examined in sediments from a 335-m deep station in the Laurentian Trough of the St. Lawrence estuary. Manganese-oxidizing bacteria were most abundant in the thin layer of oxidized surface sediment, where Mn(II) removal rates were also fastest. The first-order rate constants for Mn(II) removal decreased from 1·2 × 10 3 day −1 to 6·6 day −1 over the first 30-mm depth. In experimental slurries, sediments removed Mn(II) from reduced zone porewater by a two-step process: a rapid saturation of Mn(II) binding sites was followed by a slower O 2-enhanced removal rate which paralleled the apparent rate of Mn(II) oxidation. Sodium azide and mercuric chloride were tested specifically for their usefulness as bacterial poisons in sediment slurry systems. Sodium azide interfered with Mn(II) removal at low concentrations and was not an effective poison. Mercuric chloride inhibited bacterial activity at concentrations far lower than those at which significant interference of Mn(II) removal occurred. The response of sediment slurries treated with mercuric chloride indicated that the initial oxidation of sorbed Mn(II) was not bacterially-mediated under the experimental conditions tested.

Structure Theory for Montgomery-Samelson Fiberings between Manifolds, II

Let f: Mn→ Npbe the projection map of an MS-fibering of manifolds β with finite non-empty singular set Aand simply connected total space (see 1). Results of Timourian (10) imply that (n, p) = (4, 3), (8, 5) or (16, 9), while a theorem of Conner (2) yields that #(A), the cardinality of the singular set, is equal to the Euler characteristic of Mn. We give an elementary proof of this fact and, in addition, prove that #(A) is actually determined by bn/2(Mn), the middle betti number of Mn, or what is the same, by bn/2(Np – f(A)). It is then shown that β is topologically the suspension of a (Hopf) sphere bundle when Np is a sphere and bn/2(Mn) = 0. It follows as a corollary that β must also be a suspension when Mn is n/4-connected with vanishing bn/2. Examples where bn/2 is not zero are constructed and we state a couple of conjectures concerning the classification of such objects.