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MnZn ferrites and their magnetic, electrical, and optical properties make them highly suitable in a number of applications. These ferrites are used in electronic applications, magnetic fluids, and household appliances such as washing machines, refrigerators, and microwave ovens. This paper focuses on a hydrothermal method used to prepare a bayberry spherical manganese–zinc ferrite (Mn0.5Zn0.5Fe2O4), its surface was coated with dopamine (Mn0.5Zn0.5Fe2O4@PDA) and then carbonized to obtain the core–shell structure C-Mn0.5Zn0.5Fe2O4@PDA. Preliminary results show that carbon-coated manganese–zinc ferrite with saturation magnetic properties and coercivity increased from 99 emu and 66.01 Oe to 138 emu and 104.85 Oe, respectively. In addition, the carbonized Mn0.5Zn0.5Fe2O4@PDA (C-Mn0.5Zn0.5Fe2O4@PDA) exhibited favorable microwave absorbing performance with minimum reflection loss (RLmin) of − 17.56 dB and also revealed that the broadest effective absorption bandwidth (RLmin ≤ − 10 dB) 5.36 GHz (11.70–17.06 GHz) can be achieved at 2.0 mm. [ABSTRACT FROM AUTHOR]

Ferromagnetic order in two-dimensional (2D) van der Waals crystals has been attracting much attention recently. Remarkably, room temperature metallic ferromagnetism is realized in 2D Fe3GeTe2. Here we design a monolayer (ML) Fe3GeTe2 spin-valve device by attaching two ends to ferromagnetic electrodes and applying a magnetic field to these ferromagnetic electrodes. We investigate the spin-involved transport characteristics of such a spin valve by using ab initio quantum transport simulation. A high magnetoresistance of ∼390% is obtained and significantly increased to 450–510% after the gates are introduced. The magnetoresistance of the ML Fe3GeTe2 spin valve is insensitive to the strain modulation. Our study provides a potential option for magnetic storage applications and will motivate further studies in spintronics based on this class of materials. [ABSTRACT FROM AUTHOR]

In this study alloys with stoichiometry of R 2 Fe 17 and R 10 Fe 90-x Si x (x = 0, 10, 15, 20) (R = Y, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, and Er) have been prepared. Structural transition from the ordered rhombohedral (OR) Th 2 Zn 17 -type structure and the ordered hexagonal (OH) Th 2 Ni 17 -type structure to their disordered structures (DR and DH) has been observed according to the XRD patterns. The lattice parameters were obtained by Rietveld analysis and based on the changing characteristic of the parameters, these samples are divided into two categories: alloys with R = Ce, Pr, Nd, Sm and alloys with R = Y, Gd, Td, Dy, Ho, Er. The lattice parameters of the two categories show different changing behavior. For example, from R 2 Fe 17 to R 10 Fe 90 , the lattice parameters a decrease and c increase for the latter category, whereas for the former the lattice parameters a and c nearly have no change. In addition, increase of the ratio c/a has been found with increasing Fe or Si content, indicating the introduction of extra Fe dumbbells into the crystal cells, forming the DR or DH intermetallic compounds of R 2-y (Fe,Si) 17+2y . The obtained samples with disordered structure have shown better stability than the TbCu 7 -type metastable materials and the higher Fe concentration gives promise of higher magnetization. The mixed-rare-earth effect has also been studied in the (Ce,R) 10 Fe 75 Si 15 alloys and transition between the DR and DH structures has been realized by changing the mixed R-type or adjusting the Ce/R ratio. As for the magnetic properties, the Curie temperatures are increased remarkably by the introduction of Si and the saturation magnetizations of R 10 Fe 90-x Si x are often higher than that of the R 2 Fe 17 alloys. [ABSTRACT FROM AUTHOR]

The site preference of N atom for R2Fe14BNx (R= Pr, Nd) and the interstitial nitrogen effect on the magnetic properties have been studied by the first-principles method. It was found that the nitrogen is more likely to occupy the 4e site for Pr2Fe14BNx compound, while 4f site for Nd2Fe14BNx. When N atoms entering some specific crystal sites (such as 2a and 4f), the total magnetic moments of these compounds are not reduced, but slightly increased. Although the doping of N may reduce the total magnetic moments of some R2Fe14B compounds in the cases of optimal occupancy, the volumetric effect caused by N doping can still change the electron density distributions of Fe near the Fermi level, improving the magnetic ordering temperature of such compounds. [ABSTRACT FROM AUTHOR]

The prion hypothesis postulates that the infectious agent in transmissible spongiform encephalopathies (TSEs) is an unorthodox protein conformation based agent. Recent successes in generating mammalian prions in vitro with bacterially expressed recombinant prion protein provide strong support for the hypothesis. However, whether the pathogenic properties of synthetically generated prion (rec-Prion) recapitulate those of naturally occurring prions remains unresolved. Using end-point titration assay, we showed that the in vitro prepared rec-Prions have infectious titers of around 104 LD50 / μg. In addition, intraperitoneal (i.p.) inoculation of wild-type mice with rec-Prion caused prion disease with an average survival time of 210 – 220 days post inoculation. Detailed pathological analyses revealed that the nature of rec-Prion induced lesions, including spongiform change, disease specific prion protein accumulation (PrP-d) and the PrP-d dissemination amongst lymphoid and peripheral nervous system tissues, the route and mechanisms of neuroinvasion were all typical of classical rodent prions. Our results revealed that, similar to naturally occurring prions, the rec-Prion has a titratable infectivity and is capable of causing prion disease via routes other than direct intra-cerebral challenge. More importantly, our results established that the rec-Prion caused disease is pathogenically and pathologically identical to naturally occurring contagious TSEs, supporting the concept that a conformationally altered protein agent is responsible for the infectivity in TSEs. [ABSTRACT FROM AUTHOR]

Growth rings were used to determine the root age of medicinal Paeonia lactiflora from four producing areas, and their corresponding paeoniflorin content were measured based on the identification of ages. Different P. lactiflora root samples of different ages were collected from the four major growing areas in China: Bozhou, Anhui Province; Pan'an, Zhejiang Province; Zhongjiang, Sichuan Province; and Heze, Shandong Province. The relationship between the number of growth rings and age was analyzed using hand sections and paraffin sections. The paeoniflorin content in the roots of different P. lactiflora cultivars from different growing areas was measured using high-performance liquid chromatography (HPLC). The growth rings in the P. lactiflora roots were consistent with the age of the plant from Heze, Zhongjiang, Pan'an, whereas that for the P. lactiflora from Bozhou was one less than the age of the plant. The HPLC results show that the paeoniflorin content was highest in P. lactiflora 'Baihuachuanshaoyao,' followed by 'Baihuahangshaoyao,' 'Honghuachuanshaoyao,' and 'Honghuahangshaoyao,' 'Bozhoushaoyao' had the lowest levels of paeoniflorin. With increasing age, the paeoniflorin in the roots of the different P.lactiflora cultivars slowly declined or remained the same. In summary, the age of the roots of P. lactiflora from different growing areas can be determined using growth rings. The paeoniflorin content in the roots of P. lactiflora is correlated with cultivar and it was slowly declined with increasing age. Microsc. Res. Tech. 75:1191-1196, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Microscopic Characteristic and Chemical Composition Analysis of Three Medicinal Plants and Surface Frosts. Figure Graph: Figure 7 TIC chromatograms for Atractylodes lancea from three regions: (A) A. lancea from Tongbai Mountain, Henan Province; (a) frosts of A. lancea from Tongbai Mountain, Henan Province; (B) A. lancea from Yuexi, Anhui Province; (b) frosts of A. lancea from Yuexi, Anhui Province; (C) A. lancea from Nanjing, Jiangsu Province; (c) frosts of A. lancea from Nanjing, Jiangsu Province. Reference 1 Yu D.Q., Han X.J., Shan T.Y., Xu R., Hu J., Cheng W.X., Zha L.P., Peng H.S. Microscopic Characteristic and Chemical Composition Analysis of Three Medicinal Plants and Surface Frosts. [Extracted from the article]

Electron Beam Irradiation: Exchange Bias Effect in Epitaxial LaMnO3+ Film Induced by Electron Beam Irradiation (Adv. In article number 1901296 by Xuegang Chen, Jinbo Yang and co-workers, an interesting exchange bias effect is reported in the ferromagnetic LaMnO SB 3 sb films (blue) with antiferromagnetic clusters (red) induced by electron beam irradiation. Electron beam irradiation, exchange bias, exchange interaction, LaMnO3+ film, phase separation. [Extracted from the article]

The accumulation of chemical constituents of some medicinal plants, such as Paeonia ostii T. Hong et J. X. Zhang, Houpoëa officinalis (Rehder and E. H. Wilson) N. H. Xia and C. Y. Wu. and Atractylodes lancea (Thunb.) DC, can precipitate on the surface and form frosts after natural or artificial intervention. The characteristics of these three medicinal plants and their frosts were analyzed by light microscope, polarizing microscope, stereomicroscope, and metalloscope. The results of ordinary Raman of P. ostii and H. officinalis showed that the frosts of P. ostii matched paeonol, while that of H. officinalis matched magnolol and honokiol. In P. ostii and its frost, 19 peaks were identified by UPLC-Q/TOF-MS, and the main component was paeonol. Eleven components were identified in H. officinalis and its frosts, and the main components were magnolol and honokiol. A. lancea and its frosts were analyzed by gas chromatography-mass spectrometry (GC-MS), 21 were identified, and its main components were hinesol and β-eudesmol. These three medicinal plants accumulate compounds and precipitate frosts on the surface. The results show that the components of the frosts provide a basis for quality evaluation and research on similar medicinal plants, and reveals the scientific connotation of "taking the medicinal materials' precipitated frosts as the best" of P. ostii, H. officinalis, and A. lancea, to some extent. [ABSTRACT FROM AUTHOR]

Two unusual N -containing heterocyclic compounds, Plagranlines B-C, were isolated from the roots of Platycodon grandiflorus . Plagranline B ( 1 ) was consisted of neolignane and monomeric quinoline constituent units and plagranline C ( 2 ) possessed pyridinone ring that was not commonly discovered in natural product. Their planar structures were elucidated based on analysis of NMR and HRESIMS spectroscopy data, and their absolute configurations were determined by quantum chemical calculations, including GIAO 13 C NMR (DP4+) calculation and ECD calculation. In addition, extensive activity screening including glycosidases, oestrogen-like, and NO inhibitory assays were performed, compounds 1 and 2 possessed the weak activities.

Enterococcus faecium ( E. faecium ) is a clinical multidrug-resistant pathogen causing life-threatening infection, which makes it important to discover antibacterial agents with novel scaffolds and unique mechanism. In this study, the diarylurea scaffold was found to have potent antibacterial effect on E. faecium . Diarylurea ZJ-2 with benign drug-like property exhibited potent antibacterial and anti-biofilm activity through inhibiting the genes expression of NlpC/p60 hydrolase-secreted antigen A ( sagA ) and autolysins ( atlA ), down-regulating the expression of biofilm adherence related genes aggregation substance ( agg ), enterococcal surface protein ( esp ) against E. faecium . Moreover, ZJ-2 can be docked into SagA to inhibit daughter cell separation. In a mouse model of abdominal infection, ZJ-2 decreased the bacterial load and the level of IL-6 and TNF-α in a time-dependent manner. Overall, these findings indicated that diarylurea ZJ-2 has the potential to be developed as a therapeutic agent to treat drug-resistant enterococci and biofilm-related infections., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Xie, Wang, Yang, Zha, Zhang, Rong, Tang and Zhang.)

The scarcity of two-dimensional (2D) magnetic nanostructures has hindered their applications in spintronics, which is attributed to that most magnetic materials exhibit non-van der Waals (nvdWs) structures and it is hard to reduce their thickness to 2D nanostructures. Thus it is necessary to develop a promising strategy for free-standing 2D magnetic nvdWs nanostructures. We have achieved free-standing 2D nvdWs hexagonal FeSe with a thickness of 2.9 nm by the reaction between the oleylamine-Se complex and Fe 2+ with the assistance of Cl - , where the synergetic effects of Cl - and -NH 2 lead to anisotropic growth. Inspiringly, the 2D hexagonal FeSe exhibits intrinsic antiferromagnetic order rooted in Fe 2+ and semiconducting nature. In addition, the temperature variation would result in the chemical environment changes of Fe 2+ , responsible for the temperature-dependent magnetic transitions. This work promotes the potential applications of 2D hexagonal FeSe and the preparation of other 2D nvdWs materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Ferromagnetic order in two-dimensional (2D) van der Waals crystals has been attracting much attention recently. Remarkably, room temperature metallic ferromagnetism is realized in 2D Fe3GeTe2. Here we design a monolayer (ML) Fe3GeTe2 spin-valve device by attaching two ends to ferromagnetic electrodes and applying a magnetic field to these ferromagnetic electrodes. We investigate the spin-involved transport characteristics of such a spin valve by using ab initio quantum transport simulation. A high magnetoresistance of ∼390% is obtained and significantly increased to 450-510% after the gates are introduced. The magnetoresistance of the ML Fe3GeTe2 spin valve is insensitive to the strain modulation. Our study provides a potential option for magnetic storage applications and will motivate further studies in spintronics based on this class of materials.

Whether a genetic informational nucleic acid is required for the infectivity of transmissible spongiform encephalopathies is central to the debate about the infectious agent. Here we report that an infectious prion formed with bacterially expressed recombinant prion protein plus synthetic polyriboadenylic acid and synthetic phospholipid 1-palmitoyl-2-oleoylphosphatidylglycerol is competent to infect cultured cells and cause prion disease in wild-type mice. Our results show that genetic informational RNA is not required for recombinant prion infectivity.

Converting normal prion protein (PrP(C)) to the pathogenic PrP(Sc) isoform is central to prion disease. We previously showed that, in the presence of lipids, recombinant mouse PrP (rPrP) can be converted into the highly infectious conformation, suggesting a crucial role of lipid-rPrP interaction in PrP conversion. To understand the mechanism of lipid-rPrP interaction, we analyzed the ability of various rPrP mutants to bind anionic lipids and to gain lipid-induced proteinase K (PK) resistance. We found that the N-terminal positively charged region contributes to electrostatic rPrP-lipid binding but does not affect lipid-induced PK resistance. In contrast, the highly conserved middle region of PrP, consisting of a positively charged region and a hydrophobic domain, is essential for lipid-induced rPrP conversion. The hydrophobic domain deletion mutant significantly weakened the hydrophobic rPrP-lipid interaction and abolished the lipid-induced C-terminal PK resistance. The rPrP mutant without positive charges in the middle region reduced the amount of the lipid-induced PK-resistant rPrP form. Consistent with a critical role of the middle region in lipid-induced rPrP conversion, both disease-associated P105L and P102L mutations, localized between lysine residues in the positively charged region, significantly affected lipid-induced rPrP conversion. The hydrophobic domain-localized 129 polymorphism altered the strength of hydrophobic rPrP-lipid interaction. Collectively, our results suggest that the interaction between the middle region of PrP and lipids is essential for the formation of the PK-resistant conformation. Moreover, the influence of disease-associated PrP mutations and the 129 polymorphism on PrP-lipid interaction supports the relevance of PrP-lipid interaction to the pathogenesis of prion disease.