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Based on several reports presented valence electron structure experimental results since the 1970s, a set of new itinerant electron models for typical magnetic materials were proposed to replace the conventional exchange interaction models. According to the new models, in this article, we investigate the temperature dependence relationship between the magnetization and resistivity of typical magnetic materials. At the ground state, valence electrons of the outer shell in an ion (or in an ionic core in a metal) move in a constant spin direction. When two approaching electrons with the same spin direction belong to two adjacent ions, they can exchange each other, to form itinerant electrons. When two approaching electrons with opposite spin directions belong to two adjacent ions, they cannot exchange each other; as a result, a Weiss electron pair (WEP) is formed with a specific probability and lifetime. The energy of WEPs serves as the origin of the magnetic ordering energy. With temperature increments, the spin direction of the itinerant electrons deviates from the ground state direction, increasing the resistivity of the materials; the spin directions of the electrons in a WEP deviate from the ground state direction, resulting in the magnetic ordering energy decreasing and, meanwhile, a decrease in the magnetization. [ABSTRACT FROM AUTHOR]

Prunella vulgaris L. have high medicinal and ornamental values. It blooms in summer and then quickly withers, and there is no research on the regulatory mechanisms of flowering-related genes. Therefore, in this study, the flowering (leaves and spicas) and nonflowering (leaves) parts of P. vulgaris were sequenced with an Illumina HiSeq 4000, and 187 387 transcripts were obtained using Trinity software package. A total of 10 158 differentially expressed genes (DEGs) were found in the leaves of flowering and nonflowering P. vulgaris, with 6 294 upregulated genes and 3 864 downregulated genes. DEGs in leaves of flowering and nonflowering P. vulgaris were mainly annotated for metabolic processes (4 207) in Gene Ontology (GO) and ribosomal pathways (416) in Kyoto Encyclopedia of Genes and Genomes (KEGG). Screening of this set of genes yielded 50 flowering-related unigenes homologous to Arabidopsis genes involved in multiple regulatory pathways related to plant flowering, including autonomous, vernalization, gibberellin, and age pathways. In addition, there are significant differences in the expressions of genes related to flowering, such as PvFLC, PvSOC1, and PvFY, as well as genes involved in plant hormone signal transduction and sugar metabolism. The accuracy and reliability of the transcriptome results were verified by quantitative real-time RT-qPCR analysis of PvGA20OX, PvSVP, PvELF3, PvCRY1, and PvSOC1. Thus, we speculate that the flowering of P. vulgaris is regulated by certain genes related to the flowering regulation pathway and sugar and hormone metabolism pathways. Analysis of the P. vulgaris transcriptome will provide a basis for revealing its flowering mechanism. [ABSTRACT FROM AUTHOR]

Prunella vulgaris L. have high medicinal and ornamental values. It blooms in summer and then quickly withers, and there is no research on the regulatory mechanisms of flowering-related genes. Therefore, in this study, the flowering (leaves and spicas) and nonflowering (leaves) parts of P. vulgaris were sequenced with an Illumina HiSeq 4000, and 187 387 transcripts were obtained using Trinity software package. A total of 10 158 differentially expressed genes (DEGs) were found in the leaves of flowering and nonflowering P. vulgaris, with 6 294 upregulated genes and 3 864 downregulated genes. DEGs in leaves of flowering and nonflowering P. vulgaris were mainly annotated for metabolic processes (4 207) in Gene Ontology (GO) and ribosomal pathways (416) in Kyoto Encyclopedia of Genes and Genomes (KEGG). Screening of this set of genes yielded 50 flowering-related unigenes homologous to Arabidopsis genes involved in multiple regulatory pathways related to plant flowering, including autonomous, vernalization, gibberellin, and age pathways. In addition, there are significant differences in the expressions of genes related to flowering, such as PvFLC, PvSOC1, and PvFY, as well as genes involved in plant hormone signal transduction and sugar metabolism. The accuracy and reliability of the transcriptome results were verified by quantitative real-time RT-qPCR analysis of PvGA20OX, PvSVP, PvELF3, PvCRY1, and PvSOC1. Thus, we speculate that the flowering of P. vulgaris is regulated by certain genes related to the flowering regulation pathway and sugar and hormone metabolism pathways. Analysis of the P. vulgaris transcriptome will provide a basis for revealing its flowering mechanism. [ABSTRACT FROM AUTHOR]

To investigate the anti-explosion behavior of high-strength reinforced concrete (RC) beam subjected to blast load, the ANSYS/LS-DYNA finite element analysis software was applied. Based on anti-explosion test results, the effects of reinforcement strength grade, reinforcement ratio and stirrup ratio on dynamic response, failure mode, resistance curve and ductility of RC beams under uniform blast load were studied. The anti-explosion performance of RC beam can be effectively improved by increasing the strength grade of the high-strength reinforcement. When the shear capacity is high enough, the ultimate capacity of high-strength RC beam can be significantly enhanced by increasing its reinforcement ratio. Anti-explosion performance may deteriorate due to the change of failure modes when the reinforcement ratio is increased to a certain extent. Increasing stirrup ratio can improve the shear capacity of high-strength RC beam to guarantee the full utilization of the advantage of high flexural capacity. For high-strength RC beam with sufficiently shear capacity, the further increase of stirrup ratio has a slight effect on the anti-explosion ability. [ABSTRACT FROM AUTHOR]

Summary: Background: Epidermal barrier dysfunction is the initial event in the development of atopic dermatitis (AD). Recent studies have identified a crucial role for the aryl hydrocarbon receptor (AHR) in controlling the gene expression of filaggrin and other skin barrier proteins, suggesting an underlying association between AHR and AD pathogenesis. Aim: To investigate the role of AHR gene polymorphisms in the susceptibility to AD and in AD‐associated phenotypes. Methods: We enrolled 487 patients with AD, 210 patients with psoriasis and 226 healthy controls (HCs) from the Han Chinese population, and genotyped two AHR single‐nucleotide polymorphisms (rs10249788 and rs2066853) by PCR and subsequent DNA sequencing. Results: The AHR rs10249788 and rs2066853 polymorphisms were found in both sets of patients (AD and psoriasis) and in HCs, but no significant differences were detected in genotype or allele frequencies between the three groups. However, patients with AD with the rs10249788 (CT/TT) or rs2066853 (AG + AA) genotype were more likely to have severe dry skin scores. In the stratification analysis, the AHR rs2066853 (AG + AA) and rs10249788 (CT + TT) genotypes could predict a higher risk of severe dry skin phenotypes in the male, early‐onset and allergic rhinitis subgroups. Furthermore, the combined rs10249788 (CT + TT) and rs2066853 (AG + AA) genotypes led to a higher risk for severe dry skin in patients with AD. Conclusion: AHR polymorphisms are not associated with the risk of AD; however, they may predict a dry skin phenotype in patients with AD. [ABSTRACT FROM AUTHOR]

The Mongolian subspecies of Goitred Gazelle (Gazella subgutturosa hillieriana) belongs to Artiodactyla and Bovidae. It is widely distributed in the deserts of Inner Mongolia and Ningxia. At present, there are no studies on the genetic information characteristics of Mongolian subspecies. We determined the whole mtDNA genome of the Goitered Gazelle (G. s. hillieriana) from Ningxia Hui Autonomous Region, China. The complete mitochondrial genome is 16 435 bp in length and consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region (D-loop). The nucleotide composition is 33.90% A, 27.30% T, 13.20% G, and 25.60% C. Phylogenetic analysis results showeda close genetic relationship between G. s. hillieriana and Gazella subgutturosa subgutturosa. This study provides basic data for the subsequent genetic analysis of bovid, and is expected to fill the gap in genetic information of G. s. hillieriana. [ABSTRACT FROM AUTHOR]

Why do typical magnetic metals and oxides have different Curie temperatures (TC)? For example, TC = 1404, 1043, and 631 K for Co, Fe, and Ni, respectively; and TC = 860 and 369 K for spinel ferrite Fe3O4 and perovskite manganite La0.7Sr0.3MnO3, respectively. Until now, no satisfactory explanation for this magnetic ordering puzzle has been found although Weiss proposed the molecular field assumption for magnetic ordering in 1907. In this letter, we propose an explanation for this puzzle using a Weiss electron pair model based on atomic physics theory. [ABSTRACT FROM AUTHOR]

Powder samples of ABO3 perovskite manganites with the composition Pr0.6Sr0.4MxMn1-xO3 (M=Fe, Co, or Ni, 0.00≤x≤0.25) were synthesized using the sol-gel method. X-ray diffraction analyses showed that all three sets of samples had a single phase with an orthorhombic structure. The magnetic moment, μobs, of the samples at 10 K, decreased slowly for x≤0.10, whereas μobs decreased rapidly for x≥0.10. The dependences of μobs on the doping level x for the three series of samples were fitted successfully. In the fitting process, Mn, Fe, Co, and Ni cations were assumed to be trivalent, and the magnetic moment directions of Fe3+, Co3+, and Ni3+ cations were assumed to be canted antiferromagnetically coupled with Mn3+ cations. The cant angle φ decreased with the increase in x for x≤0.10 for Fe- and Ni-doped (x≤0.15 for Co-doped) samples and increased rapidly when x≥0.10 (x≥0.15 for Co-doped) samples. These properties are discussed using an oxygen 2p itinerant electron model, which is very similar to the oxygen 2p hole model proposed by Alexandrov et al. [ABSTRACT FROM AUTHOR]

Polypyrrole with lotus leaf shape and hollow sphere structure is synthesized as an active material and absorbing agent of sulfur for lithium-ion battery. The charge/discharge characteristics of sulfur-polypyrrole composite cathode have been investigated at different current rates. Due to the effective entrapment of polysulfide intermediates by the special structures of polypyrrole, the composites exhibit a high cycling stability with the coulombic efficiency of 92.02%, 92.31% and 94.31% after 100 cycles at the current rates of 0.2 C, 0.5 C and 1 C, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the alloying effects of minor Cu on the relationship between microstructure and corrosion resistance of (Fe0·76Si0·09B0·1P0·05)99 − xNb1Cux ( x = 0, 0·25, 0·5, 0·75, 1) ferromagnetic bulk metallic glasses (BMGs) were investigated in details. The microstructure characterisation has revealed that the introduction of proper Cu elements leads to the presence of α-Fe clusters in the as-cast amorphous rods. In addition, α-Fe nanocrystals with a suitable size and volume fraction can accelerate the formation of the protective passive layers at nanocrystals/amorphous interfaces, and lead to the improvement of corrosion resistance. However, when the Cu content x exceeds 0·75, the corrosion resistance of the FeSiBPNbCu BMGs reduces significantly. All the results imply that the Cu content plays a key role in the characteristic size of α-Fe nanoparticles embedded in the glassy matrix, and there is a dependent correlation between the corrosion resistance and the microstructure. [ABSTRACT FROM AUTHOR]

To reveal the shape change characteristics during the rolling process of the four-high hot continuous rolling mill, a three-dimensional finite element model was built with the wheel steel 380CL as the sample. The equivalent stress field, strain field, and displacement change of thickness of the wheel steel in each rolling process were analysed, and the field measurement and verification analysis were carried out. Results show that the equivalent stress, strain and thickness displacement of the strip edge gradually increases with the rolling, respectively. Reasonable tension before and after loading can effectively reduce the equivalent stress in the deformation zone and the rolling pressure required during rolling. The difference between the simulated rolling outlet thickness of 7.61 mm and the field measured thickness of 7.69 mm is small, which verifies that the calculation accuracy of the finite element is high. The conclusions obtained in this study provide a basis and reference for the development of similar wheel steel rolling calculation model. [ABSTRACT FROM AUTHOR]

Neuroprotection following ischaemic stroke is driven by the interplay between regulatory transcription factors and endogenous protective factors. IRF4, a member of the interferon regulatory factor (IRF) family, is implicated in the survival of tumour cells. However, its role in the survival of normal cells including neurons remains elusive. Using genetic approaches, we established a central role for IRF4 in protection against ischaemia/reperfusion (I/R)-induced neuronal death. IRF4 was expressed in neurons, and induced by ischaemic stroke. Neuron-specific IRF4 transgenic (IRF4-TG) mice exhibited reduced infarct lesions, and this effect was reversed in IRF4-knockout mice. Notably, we revealed that IRF4 rescues neurons from I/R-induced death both in vivo and in vitro. Integrative transcriptional and cell survival analyses showed that IRF4 functions mechanistically as a transcription activator of serum response factor (SRF) crucial to salvage neurons during stroke. Indeed, the expression of SRF and SRF-dependent molecules was significantly upregulated upon IRF4 overexpression and conversely inhibited upon IRF4 ablation. Similar results were observed in oxygen glucose deprivation (OGD)-treated primary cortical neurons. Furthermore, we identified the IRF4-binding site in the promoter region of the SRF gene essential for its transcription. To verify the IRF4-SRF axis in vivo, we generated neuron-specific SRF knockout mice, in which SRF exerted profound cerebroprotective effects similar to those of IRF4. More importantly, the phenotype observed in IRF4-TG mice was completely reversed by SRF ablation. Thus, we have shown that the IRF4-SRF axis is a novel signalling pathway critical for neuronal survival in the setting of ischaemic stroke. [ABSTRACT FROM AUTHOR]

Developing new bio-agents to control plant disease is desirable. Entomopathogenic bacteria Xenorhabdus spp. have potential antimicrobial activity in agriculture. This work was conducted to evaluate the antimicrobial activity of Xenorhabdus bovienii YL002 on plant pathogenic fungi and oomycete in vitro and the efficiency of this strain to reduce the in vivo incidence of grey mould rot on tomato plants caused by Botrytis cinerea and leaf scorch on pepper plants caused by Phytophthora capsici. The antimicrobial activity of X. bovienii YL002 was firstly determined on in vitro plant pathogenic fungi and oomycete and then on tomato fruits and plants infected with B. cinerea and pepper plants infected with P. capsici. The cell-free filtrate of X. bovienii YL002 exhibited highest inhibition effects (>98%) on mycelia growth of P. capsici and B. cinerea. The 50% inhibition concentration (EC) of the methanol-extracted bioactive compounds (methanol extract) of the cell-free filtrate against P. capsici and B. cinerea were 164·83 and 42·16 μg ml. The methanol extract also had a strong effect on the spore germination of P. capsici and B. cinerea, with a EC of 70·38 and 69·33 μg ml, respectively. At 1000 μg ml, the methanol extract showed a therapeutic effect of 70·82% and a protective effect of 77·4% against B. cinerea on tomato plants compared with the control. The methanol extract also showed potent effect against P. capsici, with a therapeutic effect of 68·14% and a protective effect of 65·46% on pepper plants compared with the control. Xenorhabdus bovienii YL002 produces antimicrobial compounds with strong activity on plant pathogenic fungi and oomycete and has the potential for controlling grey mould rot of tomato plants and leaf scorch of pepper and could be useful in integrated control against diverse plant pathogenic fungi and oomycete. This study showed the potential that X. bovienii YL002 can be used to control the grey mould rot caused by B. cinerea on tomato plants and leaf scorch caused by P. capsici on pepper plants with the objective to reduce treatments with chemical fungicides. [ABSTRACT FROM AUTHOR]

The time-averaged and low-frequency noise transport properties were investigated in the vicinity of the superconductor-insulator transition for a Bi2Sr2- x La x CuO6+δ ( x = 0.3) thin film. The results are consistent with a superconductor (metal) embedded in a strong insulator, the latter showing two-dimensional variable range hopping properties. The weak insulator behavior - if any - is attributed to the metallic inclusions only. [ABSTRACT FROM AUTHOR]

The current dependence of the excess conductivity is measured up to ≃3Tc for a Bi2Sr2CuO6+δ thin film, as a function of doping. It is found to be anomalously sensitive to the transport current and to behave as a universal function of T/Tc in the whole doping range. We discuss these results in the perspective of a granular superconductor with a gapless-like behavior. [ABSTRACT FROM AUTHOR]

This paper provides a checklist and a key to the 22 Chinese species of the nirvanine leafhopper genus Sophonia Walker. Two new species, Sophonia transvittata sp. nov. and S. yunnanensis sp. nov., are described and illustrated. The type specimens of the new species are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (IEGUC). [ABSTRACT FROM AUTHOR]

The dc and ac Josephson effects in MgB2 break junctions (BJs) and MgB2/Nb point contacts have been studied systematically. For MgB2 BJs, temperature, as well as field, the dependence of the Josephson critical currents has also been investigated. The RSJ model and Ambegaokar–Baratoff equation were successively used to fit the data obtained from these two types of junctions. Our results implicate that the MgB2 is more likely an s-wave BCS superconductor, and has its potential application in the superconducting electronics. [Copyright &y& Elsevier]

A 28S rDNA intron was used as a molecular marker to distinguish between two single spore strains of Beauveria bassiana, Bb123 and Bb151. When co-formulated and assayed against larvae of Galleria mellonella these strains exhibited no synergistic increase in virulence, rather Bb123 usually dominated. This study shows that the success of any strain to infect Galleria is dependent on the dose and method of inoculation (injection versus immersion). The result of co-formulated strains grown on solid culture also showed that usually one strain dominated, i.e., strain displacement could happen both in vivo and in vitro. The speed by which one strain was displaced following successive sub-culturing on PDA partly depended on the ratio of Bb151 and Bb123. The co-formulated inoculum could widen the window over which parent strains would be active on different water activity media. Co-infection did result in heterokaryosis within the Galleria host. Molecular studies also showed that the heterokaryon was not stable and could revert back to the parent strain. [Copyright &y& Elsevier]

To solve the common issue of transverse thickness variation in finished strip steel during the sevenstand hot continuous rolling process, the deformation of rolls in the rolling process of beam Steel 700L and the genetic characteristics of plate thickness distribution were analysed by finite element simulation. Using actual process parameters from the production of beam Steel 700L, a dynamic rolling finite element model was established. The equivalent stress field between the working rolls and strip steel in each stand and the exit thickness distribution of beam Steel 700L were investigated. Results show that the equivalent stress indicates a gradual increase despite a decreasing reduction rate during rolling. Deviations in thickness between the centre and edges of the strip steel at the exit of each stand become apparent from the second stand onwards, demonstrating a hereditary phenomenon during the rolling process. A comparison of measured and simulated thickness reveals errors within 5 %, validating the accuracy of the simulation. The obtained findings provide a foundational understanding for addressing thickness defects in subsequent beam Steel 700L production. [ABSTRACT FROM AUTHOR]

Magneto-transport properties of SrIrO3 thin films epitaxially grown on SrTiO3, using reactive RF sputtering, are investigated. A large anisotropy between the in-plane and the out-of-plane resistivities is found, as well as a signature of the substrate cubic to tetragonal transition. Both observations result from the structural distortion associated to the epitaxial strain. The low-temperature and field dependences of the Hall number are interpreted as due to the contribution of Coulomb interactions to weak localization, evidencing the strong correlations in this material. The introduction of a contribution from magnetic scatters, in the analysis of magnetoconductance in the weakly localized regime, is proposed as an alternative to an anomalously large temperature dependence of the Landé coefficient. [ABSTRACT FROM AUTHOR]

Vortex matter in layered high- T c superconductors, including iron-pnictides, undergo several thermodynamic phase transitions due to the complex interplay of pinning energy, thermal energy and elastic energy. Moreover, the presence of anisotropy makes their vortex physics even more intriguing. Here, we report a detailed vortex dynamics study, using dc magnetization measurements, in a triclinic iron-pnictide superconductor (Ca 0.85 La 0.15 ) 10 (Pt 3 As 8 )(Fe 2 As 2 ) 5 , with a superconducting transition temperature, T c ∼ 31 K. A second magnetization peak (SMP) feature is observed for magnetic field perpendicular (H ‖ c) and parallel (H ‖ ab) to the crystal plane. However, its fundamental origin is quite different in both directions. For H ‖ c, the SMP can be well explained using an elastic-to-plastic vortex creep crossover, using collective creep theory. In addition, a possible rhombic-to-square vortex lattice phase transition is also observed for fields in between the onset-field and peak-field related to the SMP. On the other hand, for H ‖ ab, a clear signature of an order-disorder vortex phase transition is observed in the isothermal M(H) measurements at T ≥ 6 K. The disordered phase exhibits the characteristics of entangled pinned vortex-liquid. We construct a comprehensive vortex phase diagram by displaying characteristic temperatures and magnetic fields for both crystal geometries in this unique superconducting compound. Our study sheds light on the intricate vortex dynamics and pinning in an iron-pnictide superconductor with triclinic symmetry. [ABSTRACT FROM AUTHOR]

A new Eu(II)-based complex [H2N(Me)2][Eu3(L)2(HCOO)2(DMF)2(H2O)](I) (H4L = 3,5'-di(3',5'-dicarboxylphenyl)pyridine) has been synthesized and structurally characterized. Single-crystal X-ray analysis (CIF file CCDC no. 1559225) reveals that compound I has 3D (4.62)(4.62)(42.67.86) topology. The emission spectra of I is dominated by four characteristic bands and shows strong luminescent feature. Furthermore, the photocatalytic properties of I for degradation of the methyl violet and Rhodamine B have been explored. [ABSTRACT FROM AUTHOR]

Multilayered combination of protective structures is an important means of effectively weakening the explosive shockwave. On this basis, a “rigid-flexible-rigid” three-layer sealed structure was proposed in this paper and two models for the sealed structure were designed. Meanwhile, internal explosion tests of the two models were conducted. One model used foam concrete as the energy absorbing material and the other used dense sand. The comparisons between the test results and the computed results obtained from the formulae were made, and the test results agreed well with the computed results. Test results showed that both models had favorable energy-dissipating capacity, and the model that used foam concrete as the energy absorbing material had a superior energy-dissipating capacity. [ABSTRACT FROM AUTHOR]

In order to obtain the target gene that affects the prognosis of osteosarcoma and to establish the risk ratio and prognosis of prediction model was the objective of the study. We obtained messenger ribonucleic acid transcriptome data from gene expression Omnibus database and clinical data from therapeutically applicable research to generate effective treatments database. Through intersection of differential genes, we obtained key genes in gene expression Omnibus database and then we used them to conduct survival analysis and establish risk ratio in therapeutically applicable research to generate effective treatments database. We obtained complement C1qA and complement C1qB as the differential key genes through GSE14359, GSE28424, GSE33382 and GSE36001 from gene expression Omnibus database. The expression of complement C1qA and complement C1qB were significantly different in 4 series data (p<0.01). Meanwhile, complement C1qA and complement C1qB have significant correlation in osteosarcoma clinical samples (p=8.61e-64, PSpearman=0.97, 95 % confidence interval (0.96-0.98). The survival time of over-expression of complement C1qA and complement C1qB samples were significantly prolonged (p=0.0026 and p=0.006), area under the curve=0.689 (95 % confidence interval, 0.575-0.804), 0.702 (95 % confidence interval, 0.595-0.809), 0.641 (95 % confidence interval, 0.513-0.768) respectively. Complement C1qA and complement C1qB over-expression can significantly prolong survival time and can be used as predictors of survival in osteosarcoma. [ABSTRACT FROM AUTHOR]

A promising accelerator light source mechanism called steady-state microbunching (SSMB) is being actively studied. With the combination of strong coherent radiation from microbunching and high repetition rate of a storage ring, high-average-power narrow-band radiation can be anticipated from an SSMB storage ring, with wavelengths ranging from THz to soft X-ray. Such a novel light source could provide new opportunities for accelerator photon science like high-resolution angle-resolved photoemission spectroscopy and industrial applications like extreme ultraviolet (EUV) lithography. In this paper, a theoretical and numerical study of the average and statistical properties of coherent radiation from SSMB are presented. The results show that 1 kW average-power quasi-continuous-wave EUV radiation can be obtained from an SSMB ring provided that an average current of 1 A and a microbunch train with bunch length of 3 nm can be formed at the radiator which is assumed to be an undulator. Together with the narrow-band feature, the EUV photon flux can reach 6 × 1015 photons s-1 within a 0.1 meV energy bandwidth, which is three orders of magnitude higher than that in a conventional synchrotron source and is appealing for fundamental condensed matter physics and other research. In this theoretical investigation, we have generalized the definition and derivation of the transverse form factor of an electron beam which can quantify the impact of its transverse size on coherent radiation. In particular, it has been shown that the narrow-band feature of SSMB radiation is strongly correlated with the finite transverse electron beam size. Considering the pointlike nature of electrons and quantum nature of radiation, the coherent radiation fluctuates from microbunch to microbunch, or for a single microbunch from turn to turn. Some important results concerning the statistical properties of SSMB radiation are presented, with a brief discussion on its potential applications, for example the beam diagnostics. The presented work is of value for the development of SSMB to better serve potential synchrotron radiation users. In addition, this also sheds light on understanding the radiation characteristics of free-electron lasers, coherent harmonic generation, etc. [ABSTRACT FROM AUTHOR]

Powder samples of the ferrites MxMn1-xFe2O4 (M = Zn, Mg, Al) were prepared using a chemical co-precipitation method. X-ray diffraction analysis showed that the three series of samples had a single-phase cubic spinel structure and that there was a decrease in the lattice parameters with increasing x. There were different dependences on the doping level x of the magnetic moments (µexp) for the three series of samples measured at 10 K. We found a non-monotonic behavior for µexp as a function x for the Zn doped samples with a maximum at x = 0.4, while µexp decreased monotonically with increasing x for the Mg and Al doped samples. On the basis of the O2p itinerant electron model, the magnetic moment direction of the Mn3+ cations is expected to be antiparallel to those of the Mn2+ and Fe cations in these samples. With this assumption, the curves of µexp versus x for the three series of samples were fitted using a quantum-mechanical potential barrier model earlier proposed by our group, and the cation distributions were obtained. [ABSTRACT FROM AUTHOR]

Ferrite powder samples of Mn xNi1- xFe2O4 (0.0 ≤ x ≤ 1.0) with single phase (A)[B]2O4 spinel structure were prepared using a sol-gel method. Following the successful proposal by our group, that the magnetic moment directions of Cr2+ (3d4) cations are antiparallel to those of Fe3+ (3d5) and Fe2+ (3d6) cations in a given sublattice of the Cr-doped spinel ferrites due to the constraints imposed by Hund's rules, we extend here the same idea and assume that the magnetic moment directions of Mn3+ (3d4) cations are also antiparallel to those of Mn2+ (3d5) and divalent and trivalent Fe (Ni) cations in a given sublattice of Mn-doped spinel ferrites. We have thereby obtained cation distributions for the samples by fitting the magnetic moments of the samples at 10 K. The results indicate that 72% of the Mn cations occupy the [B] sites in MnFe2O4, which is close to the results for Ni (82%) in NiFe2O4, but is different from the result obtained using the conventional view which yields 80% of the Mn cations in the (A) sites of MnFe2O4. On the basis of the present analyses of the magnetic structure of Mn xNi1- xFe2O4 (0.0 ≤ x ≤ 1.0), we propose here a new model for spinel ferrites that is distinctly different from both the super- and the double-exchange model and that we refer to as the O2p itinerant electron model. Using this model, not only can the magnetic structure of the spinel ferrites MFe2O4 ( M = Fe, Co, Ni, and Cu) be explained better than by using the super- and double-exchange interaction models, but also the magnetic structure and the cation distributions of Cr-, Mn-, and Ti-doped spinel ferrites can be explained. [ABSTRACT FROM AUTHOR]

Ti-doped Ni0.68Fe2.32O4 spinel ferrite samples with nominal composition Ni0.68−0.8 xTi xFe2.32−0.2 xO4 (0 ≤ x ≤ 0.312) were prepared using conventional ceramic methods. The samples exhibited a single-phase cubic spinel structure. When the doping level had values x > 0.15, a transition temperature, TN, was found, below which the magnetization of the samples decreased with decreasing measurement temperature. This phenomenon indicates that an additional antiferromagnetic structure arises in the traditional spinel phase of ferrites resulted from Ti doping. Therefore, Ti ions appear in the form of Ti3+ and Ti2+ cations that have magnetic moments, rather than as Ti4+ cations without magnetic moment as assumed by many researchers. The dependence of the magnetic moments on the Ti doping level x at 10 K was fitted successfully using our quantum-mechanical potential barrier model proposed earlier. In the fitting process, we assumed that the magnetic moments of the Ti cations were opposite to the direction of the Fe and Ni moments. According to the fitted results, the Ti2+ cations at the [B] sites constitute about 81% of the total Ti content x for all samples, which is close to the content of the Ni2+ cations at the [B] sites (77%). [ABSTRACT FROM AUTHOR]

Powder samples of the ferrites MxNi1-xFe2O4 (M = Cr, Co and 0.0 ≤ x ≤ 0.3) were prepared using a chemical co-precipitation method. X-ray diffraction analysis showed that the two series of samples had a single-phase cubic spinel structure. It was found that the magnetic moments (μexp) per formula of samples measured at 10 K decreased when Cr substituted for Ni, but increased when Co substituted for Ni, in spite of the fact that the magnetic moments of Cr2+ (4 μB) and Co2+ (3 μB) are higher than that of Ni2+ (2 μB). With the assumption that the magnetic moments of Cr2+ and Cr3+ lie antiparallel to those of the Fe, Co, and Ni cations in the same sublattices of spinel ferrites, the dependences on the Cr (Co) doping level of the sample magnetic moments at 10 K were fitted successfully, using the quantum-mechanical potential barrier model earlier proposed by our group. For the two series of samples, the fitted magnetic moments are close to the experimental results. [ABSTRACT FROM AUTHOR]

Ionic size is considered to be an important factor influencing the unit cell volume of manganites with an ABO3 structure. For La1-xSrxMnO3, however, although the average effective ion radius of all cations taken together increases with increasing x, the unit cell volume decreases for x<0.5. In the case of La1-xNaxMnO3, the unit cell volume reaches a minimum when x=0.3. Up to now, no satisfactory explanation of these phenomena has been found. In this letter, an explanation based on the ionic cohesive energy with a small additional metallic cohesive energy is described. [ABSTRACT FROM AUTHOR]

The effects of the vacancy at the B sites on the structural and magnetic properties of perovskite manganites with a nominal composition La0.75Sr0.25Mn1-xO3 (0.0 ≤ x ≤ 0.13), prepared by the sol-gel method, were investigated. X-ray diffraction patterns indicate that there is a ABO3 perovskite structure single phase in the samples with x ≤ 0.08; however, there are second and third phases containing La, except ABO3 perovskite phase, in the samples with x ≥ 0.10. Magnetic measurement indicates that the sample with x = 0.08 has the lowest Curie temperature. By a quantitative phase analysis, we believe that there is a maximum value of vacancy content at the B sites in ABO3 perovskite manganites. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the dry matter (DM) and crude protein (CP) degradation parameters of several commercially available concentrate feed ingredients used in Shaanbei White Cashmere Goat (SWCG). Three 4-year-old female SWCGs fitted with permanent rumen fistula were fed with corn straw and concentrate feed. Tested energy and protein feed ingredients were corn, wheat bran (WB), corn germ meal, soybean meal (SBM), rape seed meal (RSM), and distillers dried grains. The feed samples were placed in a nylon bag and incubated in the rumen for 0, 2, 6, 12, 24, 36, and 48 h to measure the ruminal disappearance of DM and CP. The exponential model was used to calculate the degradation kinetics. There were significant differences between sources in terms of DM and CP disappearance and degradability. In terms of energy feed ingredients, the potential degradability of DM and CP of corn was significantly higher than those of the other energy feed ingredients, whereas the effective degradability (ED) of CP of WB at three outflow rates was significantly higher than those of the others. In protein feed ingredients, SBM had the highest potential degradability of DM and CP. Furthermore, the ED of DM of SBM at three outflow rates was significantly higher than those of the other protein feed ingredients, whereas the ED of CP of RSM at three outflow rates was significantly higher than those of others. Those feed ingredients with low degradability can increase the bypass nutrients, which will be digested in the small intestine. The degradation parameters obtained in this experiment using SWCG would be useful in improving the accuracy of formulation of cashmere goat diet in Northwest of China. [ABSTRACT FROM AUTHOR]

Summary: This study described a modified quantitative morphometry (mQM) system adapted to specific reference values for Mainland Chinese population. The mQM system is validated using the Genant Semiquantative system and is sensitive for detecting vertebral height changes and predicting cement leakage after percutaneous kyphoplasty (PKP) in patients with osteoporotic vertebral compressive fracture (OVCF).Introduction: OVCF is a manifestation of osteoporosis. To improve clinical management of osteoporosis, the quantitative morphometry (QM) system has been widely used for the early diagnosis and precise classification of OVCF in developed countries. Here, we present an mQM system and validated its use in detecting OVCF in Mainland Chinese.Methods: Using our mQM system, the pre- and post-operative values of vertebral heights were measured and evaluated in 309 Mainland Chinese who received percutaneous kyphoplasty (PKP) as OVCF treatment. Measurements and classification of fractures from the mQM system were validated by comparing to values obtained by the Genant semiquantative (SQ) method. Moreover, we evaluated the sensitivity of the mQM system by its ability to detect restoration of vertebral heights and predict cement leakage after PKP.Results: The five classification of fractures, No deformity (ND), anterior wedge (AW), posterior wedge (PW), biconcavity (BC), and compression (CP), evaluated by the mQM method shared similar distribution characteristics compared to those obtained by the SQ method. In addition, mQM evaluation showed that the vertebra height of all fracture types showed significant restoration after PKP. The incidence of cement leakage was most common in CP (37.5%), followed by AW (31.6%), BC (26.5%), ND (23.7%), and PW (0.0%).Conclusions: Our mQM system is suitable for classification of fractures, detection of vertebral height restoration, and correlation of cement leakage after PKP in Mainland Chinese population. [ABSTRACT FROM AUTHOR]

Powder samples of the ABO3 perovskite manganites Pr0.6Sr0.4CrxMn1-xO3 (0.00≤x≤0.30) were synthesized using the sol-gel method. X-ray diffraction analyses showed that all the samples had a single-phase orthorhombic structure. By analyzing magnetic parameters on the basis of the O2p itinerant electron model, we found that there are two magnetic transition temperatures, TCM and TCP, corresponding to changes in the magnetic ordering for the Mn and Pr cations, respectively. The magnetic moments of Mn3+ and Cr3+ cations within the B sublattice show canted ferromagnetic coupling, and the magnetic moments of the Pr cations within the A sublattice also show canted ferromagnetic coupling. However, the total magnetic moment of the A sublattice shows antiferromagnetic coupling against that of the B sublattice. The assumption of the canted ferromagnetic coupling within the B sublattice was confirmed using magnetoresistance experimental results. [ABSTRACT FROM AUTHOR]

A new type of composite concrete which can be called corundum-rubble concrete (CRC) was presented to improve the resistance of protective structure to the projectile impact. Comparative experiments were conducted between CRC and reinforced concrete, and a modified Taylor model was proposed to predict the penetration depth of CRC targets. Experimental results show that CRC is much higher than reinforced concrete in both strength and hardness and shows excellent resistance to the 0.125 m-diameter projectile impact. Theoretical analyses demonstrated that the modified Taylor model’s predicted results were in good agreement with the measured values. [ABSTRACT FROM AUTHOR]

The oxygen vacancy model has been used to explain the magnetic and electrical transport properties of dilute magnetic semiconductors and resistive switching. In particular, some authors have claimed that they found a symmetric peak corresponding to the oxygen vacancies in O1s photoelectron spectra. In this paper, using X-ray photoelectron spectra with argon ion etching, it is shown that this symmetric peak may also be interpreted as being related to O1- anions, rather than to oxygen vacancies. [ABSTRACT FROM AUTHOR]

Fe-Ni-W amorphous alloy platings were electrodeposited on the surface of S135 steel, and heat treatments at 125, 165, 205, 255, 305, 355 and 405°C were carried out on them. Corrosion resistance, hardness, structure and morphology of Fe-Ni-W amorphous alloys have been tested and analysed by means of polarisation curve, hardness test, X-ray diffraction and scanning electron microscopy, respectively. The results show that the as-plated Fe-Ni-W alloys are amorphous under this experimental condition. Autoclave corrosion test, together with polarisation curve results and general corrosion experiment, indicates that the best heat treatment temperature of Fe-Ni-W alloy electrodeposited on S135 steel is 165°C in this paper. [ABSTRACT FROM AUTHOR]

The average valence, ValO, of the oxygen anions in the perovskite oxide BaTiO3, was found using O1s photoelectron spectra to be -1.55. This experimental result is close to the theoretical value for BaTiO3 (-1.63) calculated by Cohen [Nature 358,136 (1992)] using density functional theory. Using the same approach, we obtained values of VaiO for several monoxides, and investigated the dependence of ValO and the ionicity on the second ionization energy, V(M2+), of the metal cation. We found that the dependence of the ionicity on V(M2+) in this work is close to that reported by Phillips [Rev. Mod. Phys. 42, 317 (1970)]. We therefore suggest that O1s photoelectron spectrum measurements should be accepted as a general experimental method for estimating the ionicity and average valence of oxygen anions. [ABSTRACT FROM AUTHOR]

Powder samples of the spinel ferrites MxNi0.7-xFe2.3O4 (M = Cr, Co and 0.0 ≤ x ≤ 0.3) and CrxNi0.7Fe2.3-xO4 (0.0 ≤ x ≤ 0.3) were synthesized using the chemical co-precipitation method. The XRD spectra confirmed that the samples had a singlephase cubic spinel structure. Magnetic measurements showed that the magnetic moments (μexp) per formula both at 10 K and 300 K increased with Co substitution, while the values of μexp decreased with Cr substitution. Applying the assumption that the magnetic moments of Cr2+ and Cr3+ lie antiparallel to those of the divalent and trivalent Fe, Co, and Ni cations in the same sublattice of spinel ferrites, these interesting behaviors could be easily interpreted. The cation distributions of the three series of samples were estimated successfully by fitting the dependences of μexp, measured at 10 K, on the doping level x, using a quantum-mechanical potential barrier model earlier proposed by our group. The results obtained for the Cr cation distributions at the (A) and [B] sites are very close to those obtained elsewhere using neutron diffraction. [ABSTRACT FROM AUTHOR]

We perform time-resolved photoelectron spectroscopy measurements of optimally doped Bi2Sr2CaCu2C>8+δ (Bi-2212) and Bi2Sr2-xLaxCuO6+δ (Bi-2201). The electron dynamics shows that inelastic scattering by nodal quasiparticles decreases when the temperature is lowered below the critical value of the superconducting phase transition. This drop in electronic dissipation is astonishingly robust and survives to photoexcitation densities much larger than the value sustained by long-range superconductivity. The unconventional behavior of quasiparticle scattering is ascribed to superconducting correlations extending on a length scale comparable to the inelastic path. Our measurements indicate that strongly driven superconductors enter in a regime without phase coherence but finite pairing amplitude. The latter vanishes near to the critical temperature and has no evident link to the pseudogap observed by angle-resolved photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

The effects of nanoparticles with different shapes on the interface bond energy in a polyimide/KTa0·5Nb0·5O3 composite were investigated using molecular dynamic simulations. The simulation results showed that the bond energy of sphere particles were 20-85 kcal mol−1, whereas the bond energies of three shape nanoparticles surface atoms (cube, cylinder and cone) were 5-30 kcal mol−1. This indicated that Van der Waals force and hydrogen bonds existed between the matrix and the fillers. The bond strengths of the small nanoparticles were more than the larger nanoparticles due to the size effect. At the same doping volume fraction, the bond energy of the sphere nanoclusters was significantly larger than the ones of other shaped nanoparticles. The introduction of sphere nanoparticles and the small-sized nanoparticles has the potential to be an effective way to improve the properties of the polyimide/KTa0·5Nb0·5O3 composites. [ABSTRACT FROM AUTHOR]

Adiabatic shear band is an important materials phenomenon often observed in metals when processed at high strain rates. The mechanical responses and microstructure evolution in it attract strong interests from the scientists of materials science and engineering. We report the results of the microstructure characteristic of a 200 series Fe-Cr-Ni austenitic stainless steel with low nickel contents deformed at high strain rates (about 5.8x10=sup=5=/sup=s=sup=-1=/sup=) by a split Hopkinson pressure bar. The hat shaped specimens are used to induce the formation of the adiabatic shear bands under shock-loading tests. The microstructure and microtexture of the shear band in a 200 series Fe-Cr-Ni austenitic stainless steel are investigated by means of optical micrograph electron backscatter diffraction. The shear bands can be generated at about 78μs after the true flow stress reaches the value about 923MPa. The grains in the boundary of the shear band are elongated along the shear direction, and the core of the shear band consists of ultrafine equiaxed grains with diameter 0.1-0.3μm and low dislocation density. According to the orientation distribution, the microtexture peaked at (45°, 65°, 0°) in the matrix slightly shifts towards the recrystallization microtexture (60°, 60°, 0°) in the shear band center, and the grain boundaries in the shear band are geometrical necessary boundaries with high-angles. Calculations of temperature rise about 943K suggest that the temperature in the shear band is above the recrystallization point. Finally, the grain refinement in an adiabatic shear band in the 200 series Fe-Cr-Ni austenitic stainless steel is described as a consequence of the rotational dynamic recrystallization. [ABSTRACT FROM AUTHOR]

The study aims to investigate the efficacy of piroline and other antibiotics in the treatment of bovine mastitis caused by Streptococcus uberis and Escherichia coli during dry-milk period. A total of 1880 cows in dry-milk period were divided into 4 groups and treated with penicillin G, ammonia benzyl penicillin, ceftiofur and piroline, respectively. The efficac for mastitis caused by E. coli were 31.2% for penicillin G, 36.9% for ammonia benzyl penicillin, 61.3% for ceftiofur, and 64.4% for piroline. For mastitis caused by S. uberis, the efficacies are 90% for ceftiofur and 94.4% for piroline. The results indicated that piroline was more effective than the other three in treating the disease. The post-treatment analysis on milk samples demonstrated absence of piroline residueÿHence, piroline could be used as therapeutic agent in treating mastitis. [ABSTRACT FROM AUTHOR]

A key question in condensed-matter physics is to understand how high-temperature superconductivity emerges on adding mobile charged carriers to an antiferromagnetic Mott insulator. We address this question using angle-resolved photoemission spectroscopy to probe the electronic excitations of the non-superconducting state that exists between the Mott insulator and the d-wave superconductor in Bi2Sr2CaCu2O8+δ. Despite a temperature-dependent resistivity characteristic of an insulator, the excitations in this intermediate state have a highly anisotropic energy gap that vanishes at four points in momentum space. This nodal-liquid state has the same gap structure as that of the d-wave superconductor but no sharp quasiparticle peaks. We observe a smooth evolution of the excitation spectrum, along with the appearance of coherent quasiparticles, as one goes through the insulator-to-superconductor transition as a function of doping. Our results suggest that high-temperature superconductivity emerges when quantum phase coherence is established in a non-superconducting nodal liquid. [ABSTRACT FROM AUTHOR]

The response of a material to external stimuli depends on its low-energy excitations. In conventional metals, these excitations are electrons on the Fermi surface—a contour in momentum (k) space that encloses all of the occupied states for non-interacting electrons. The pseudogap phase in the copper oxide superconductors, however, is a most unusual state of matter. It is metallic, but part of its Fermi surface is ‘gapped out’ (refs 2, 3); low-energy electronic excitations occupy disconnected segments known as Fermi arcs. Two main interpretations of its origin have been proposed: either the pseudogap is a precursor to superconductivity, or it arises from another order competing with superconductivity. Using angle-resolved photoemission spectroscopy, we show that the anisotropy of the pseudogap in k-space and the resulting arcs depend only on the ratio T/T*(x), where T*(x) is the temperature below which the pseudogap first develops at a given hole doping x. The arcs collapse linearly with T/T*(x) and extrapolate to zero extent as T→0. This suggests that the T=0 pseudogap state is a nodal liquid—a strange metallic state whose gapless excitations exist only at points in k-space, just as in a d-wave superconducting state. [ABSTRACT FROM AUTHOR]

Angle resolved photoemission spectroscopy (ARPES) has been used to investigate the shadow bands present at the Fermi surface of bismuth based superconductors. Bi2Sr2CaCu2O8+δ (Bi2212) single crystals with different doping levels and Bi2Sr2CuO6+δ (Bi2201) thin films have been studied by means of momentum distribution curves along the ΓY high symmetry direction in two different Brillouin zones and for an extensive photon energy range. The results show an enhancement of the shadow band intensity in the second Brillouin zone for photon energies around hν=30 eV. Furthermore, the ratio Shadow Bands/Main Band is shown to be constant as a function of both the doping level and the number of CuO2 planes. An interpretation of this observation on the basis of the current theoretical models will be provided. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the pulmonary arterial pressure in children with nephrotic syndrome (NS). Methods: Doppler echocardiography was performed in 40 children with NS (aged 1.5-13 years) at NS onset (n = 28) or relapse (n = 12), and 40 normal controls. Pulmonary pressure was estimated by: (1) measuring the systolic transtricuspid gradient from tricuspid regurgitation; and (2) measuring the time to peak velocity of pulmonary flow. Results: Thirty five of the 40 patients with NS had measurable tricuspid regurgitation with a pulmonary systolic pressure ranging from 21 to 48 mm Hg. Pulmonary systolic pressure was >40 mm Hg in seven patients. The pulmonary time to peak velocity was shortened and the ratio of time to peak velocity and right ventricular ejection time decreased compared with controls. The patients with increased pulmonary pressure had a longer time since onset of NS. One patient developed thrombus in the inferior vena cava during hospitalisation. Conclusion: Pulmonary arterial pressure was increased in children with NS. Further work is needed to evaluate the aetiology and clinical implications of this abnormality. [ABSTRACT FROM AUTHOR]

A quantum-mechanical method for estimating the cation distribution in spinel ferrites is proposed, by which the ionization energy of the cations and the Pauli repulsion energy is considered, together with the magnetic ordered energy and the tendency toward charge density balance. Using this method, not only can the difference between the observed and the traditional theoretical magnetic moments of the spinel structure ferrites MFe2O4 (M=Mn,Fe,Co,Ni,Cu) be explained, but also the dependence of the magnetic moments of the ferrites M1-xZnxFe2O4 (M=Mn,Fe,Co,Ni,Cu) on the doping level x can be fitted. [ABSTRACT FROM AUTHOR]

We report the crystal growth of a new compound, Yb3Os4Ge13, by using a Bi flux method. X-ray diffraction measurement reveals that it crystallizes in the quasiskutterudite-type caged structure with a cubic space group of Pm3n (No. 223). Magnetic measurements reveal almost fully localized Yb 4f-moments above 120 K. The resistivity exhibits a logarithmic increase below ~40 K. The specific heat coefficient shows a rapid upturn below ~5K and exceeds 2Jmol-1K-2 at 2 K. Our experimental analysis and electronic band structure calculations demonstrate that Yb3Os4Ge13 exhibits the Kondo effect due to strong hybridization of the localized Yb f moments with the p electrons of the surrounding Ge cages. [ABSTRACT FROM AUTHOR]