[Establishment of a topographic map assessment system for facial and cervical wounds and scars of burn patients based on the Delphi method].

Objective: To construct a targeted and accurate evaluation system for facial and cervical wounds and scars of burn patients. Methods: The method combining literature analysis and survey research was adopted, and the basic principles of item system construction were followed. From June to August 2020, based on the aesthetic standards of facial and cervical plastic surgery, the topographic map assessment system for facial and cervical wounds and scars of burn patients was preliminarily formed, focusing on the assessment of wounds and scars in the necks and faces of patients after burns. In September 2020, 38 experts in the relevant fields were consulted in advance and the questionnaire was revised according to the experts' opinions. From December 2020 to March 2021, the Delphi method was applied to conduct inquiry by correspondence with 35 experts in relevant fields from Guangzhou, Shenzhen, Shanghai, Beijing, and other cities, who met the inclusion criteria, and the items were screened and established. The effective recovery rate of inquiry questionnaire was calculated to determine the level of enthusiasm of experts, the average authority coefficient of all items was calculated to determine the level of expert authority, the average importance expert score, the average coefficient of variation, and the average full score rate of all the third-level items were calculated to determine the concentration of expert opinions, the average coefficients of variation and Kendall's harmony coefficients of the importance, sensitivity, and operability expert scores of all the third-level items were calculated to determine the degree of coordination of expert opinions. The Kendall's harmony coefficients for the importance, sensitivity, and operability expert scores of all the third-level items were statistically analyzed with chi-square test. Results: Among the 35 experts consulted by Delphi method, mainly were male, aged (48±10) years, with 8-38 years of working experience, mainly with associate senior titles and above, all with a bachelor's degree or above education background, and of whom 11 were burn experts, 7 were wound repair experts, 4 were plastic surgery experts, and 13 were rehabilitation medicine experts. Finally, a topographic map assessment system for facial and cervical wounds and scars of burn patients was formed, including 4 first-level items, 21 second-level items, 40 third-level items, and 1 mask. The effective recovery rate of inquiry questionnaire was 100% (35/35). The average authority coefficient of all items was 0.89. The average importance expert score was 4.67, the average coefficient of variation of importance expert score was 0.01, and the average full score rate of all the third-level items was 86.3%. The average coefficients of variation of the importance, sensitivity, and operability expert scores of all the third-level items were 0.01, 0.01, and 0.02, respectively. The Kendall's harmony coefficients for the importance, sensitivity, and operability expert scores of all the third-level items were statistically significant (with χ2 values of 1 201.53, 745.67, and 707.07, respectively, P<0.05). Conclusions: The established topographic map assessment system for facial and cervical wounds and scars of burn patients has high scientificity and reliability, which can be used for the evaluation of facial and neck wounds or scars in burn patients.

Itaconic acid and dimethyl itaconate exert antibacterial activity in carbon-enriched environments through the TCA cycle.

Itaconic acid (IA), a metabolite generated by the tricarboxylic acid (TCA) cycle in eukaryotic immune cells, and its derivative dimethyl itaconate (DI) exert antibacterial functions in intracellular environments. Previous studies suggested that IA and DI only inhibit bacterial growth in carbon-limited environments; however, whether IA and DI maintain antibacterial activity in carbon-enriched environments remains unknown. Here, IA and DI inhibited the bacteria with minimum inhibitory concentrations of 24.02 mM and 39.52 mM, respectively, in a carbon-enriched environment. The reduced bacterial pathogenicity was reflected in cell membrane integrity, motility, biofilm formation, AI-2/luxS, and virulence. Mechanistically, succinate dehydrogenase (SDH) activity and fumaric acid levels decreased in the IA and DI treatments, while isocitrate lyase (ICL) activity was upregulated. Inhibited TCA circulation was also observed through untargeted metabolomics. In addition, energy-related aspartate metabolism and lysine degradation were suppressed. In summary, these results indicated that IA and DI reduced bacterial pathogenicity while exerting antibacterial functions by inhibiting TCA circulation. This study enriches knowledge on the inhibition of bacteria by IA and DI in a carbon-mixed environment, suggesting an alternative method for treating bacterial infections by immune metabolites.

[Analysis of the clinical characteristics and therapeutic effect of refractory juvenile dermatomyositis to tofacitinib].

Objective: To elucidate the clinical features of patients with refractory juvenile dermatomyositis (JDM), and to explore the efficacy and safety of tofacitinib in the treatment of refractory JDM. Methods: A total of 75 JDM patients admitted to the Department of Rheumatology and Immunology in Shenzhen Children's Hospital from January 2012 to January 2021 were retrospectively analyzed, and to analyze the clinical manifestations, efficacy and safety of tofacitinib in the treatment of refractory JDM. Patients were divided into refractory group with using of glucocorticoids in combination with two or more anti-rheumatic drugs for treatment, and the presence of disease activity or steroid dependence after a one-year follow-up. The non-refractory group is defined as clinical symptoms disappeared, laboratory indicators were normal, and clinical remission was achieved after initial treatment, and the clinical manifestations and laboratory indexes of the two groups were compared. The Mann-Whitney U test, Fisher's precision probability test was used for intergroup comparison. Binary Logistic multivariate regression analysis was used to identify risk factors for refractory JDM. Results: Among the 75 children with JDM, 41 were males and 34 were females with a age of onset of 5.3 (2.3, 7.8) years. The refractory group consisted of 27 cases with a age of onset of 4.4 (1.5, 6.8) years, while the non-refractory group consisted of 48 cases with a age of onset of 5.9 (2.5, 8.0) years. Compared with 48 cases in the non-refractory group, the proportion of interstitial lesions and calcinosis in the refractory group was higher than that in the non-refractory group (6 cases (22%) vs. 2 cases (4%), 8 cases (30%) vs. 4 cases (8%), both P<0.05). Binary Logistic regression analysis showed that observation group were more likely to be associated with to interstitial lung disease (OR=6.57, 95%CI 1.22-35.31, P=0.028) and calcinosis (OR=4.63, 95%CI 1.24-17.25, P=0.022). Among the 27 patients in the refractory group, 22 cases were treated with tofacitinib, after treatment with tofacitinib, 15 of 19 cases (86%) children with rashes showed improvement, and 6 cases (27%) with myositis evaluation table score less than 48 score both were improved, 3 of 6 cases (27%) had calcinosis were relieved, and 2 cases (9%) had glucocorticoid-dependence children were successfully weaned off. During the tofacitinib treatment, there was no increase in recurrent infection, blood lipids, liver enzymes, and creatinine were all normal in the 22 cases. Conclusions: Children with JDM with calcinosis and interstitial lung disease are more likely to develop refractory JDM. Tofacitinib is safe and effective for refractory JDM.

[Association of hs-CRP with frailty and its components among the elderly over 65 years old in 9 longevity areas of China].

Objective: To investigate the association of the levels of high sensitivity C-reactive protein (hs-CRP) with frailty and its components among the elderly over 65 years old in 9 longevity areas of China. Methods: Cross-sectional data from the Health Ageing and Biomarkers Cohort Study (HABCS, 2017-2018) were used and the elderly over 65 years old were included in this study. Through questionnaire interview and physical examination, the information including demographic characteristics, behavior, diet, daily activity, cognitive function, and health status was collected. The association between hs-CRP and frailty and its components in the participants was analyzed by multivariate logistic regression model and restrictive cubic spline. Results: A total of 2 453 participants were finally included, the age was (84.8±19.8) years old. The median hs-CRP level was 1.13 mg/L and the prevalence of frailty was 24.4%. Compared with the low-level group (hs-CRP<1.0 mg/L), the OR (95%CI) value of the high-level group (hs-CRP>3.0 mg/L) was 1.79 (1.35-2.36) mg/L. As for the components, the hs-CRP level was also positively associated with ADL disability, IADL disability, functional limitation and multimorbidity. After adjusting for confounding factors, compared with the low-level group, the OR (95%CI) values of the high-level group for the four components were 1.68 (1.25-2.27), 1.88 (1.42-2.50), 1.68 (1.31-2.14) and 1.39 (1.12-1.72), respectively. Conclusion: There is a positive association between the levels of hs-CRP and the risk of frailty among the elderly over 65 years old in 9 longevity areas of China. The higher hs-CRP level may increase the risk of frailty by elevating the risk of four physical functional disabilities, namely ADL disability, IADL disability, functional limitation and multimorbidity.

Probiotic characterization and comparison of broiler-derived lactobacillus strains based on technique for order preference by similarity to ideal solution analysis.

A total of 10 lactobacillus strains were isolated from broiler chickens and their probiotic properties including tolerance to gastrointestinal fluids and heat treatment, antimicrobial activity, adhesion capacity to intestinal cells, surface hydrophobicity, autoaggregation, antioxidative activity, and immunomodulatory effects on chicken macrophages were evaluated. The Limosilactobacillus reuteri (LR) was the most frequently isolated species, followed by Lactobacillus johnsonii (LJ) and Ligilactobacillus salivarius (LS). All isolates showed good resistance to simulated gastrointestinal conditions and antimicrobial activity against 4 indicator strains including Escherichia coli, Salmonella typhimurium, Klebsiella pneumoniae, and Proteus mirabilis LR 21 exhibited excellent performances on autoaggregation, hydrophobicity and adhesion capacity to Caco-2 intestinal cells. In the meantime, this strain also possessed considerable tolerance to heat treatment, which indicated great potential to be used in the feed industry. However, LJ 20 strain had the highest free radical scavenging activity compared with the other strains. Furthermore, qRT-PCR results revealed that all isolated strains significantly increased the transcriptional levels of proinflammatory genes and tended to induce the M1-type polarization on HD11 macrophages. Particularly, the technique for order preference by similarity to ideal solution (TOPSIS) was adopted in our study to compare and select the most promising probiotic candidate based on in vitro evaluation tests.

Effects of early post-hatch feeding on the growth performance, hormone secretion, intestinal morphology, and intestinal microbiota structure in broilers.

This study aimed to investigate the effects of time access to post-hatch feeding on the growth performance, hormone secretion, intestinal morphology, and intestinal microbiota structure of broilers. A total of 900 broilers were randomly allocated to 3 treatment groups, with 6 replicates of 50 broilers each. The 3 treatments were: immediate feeding (Group 2 h), delayed access to feed for 24 h (Group 24 h), and delayed access to feed for 48 h (Group 48 h). The experiment lasted for 50 d. Results revealed that Group 2 h had a higher average daily gain (ADG) and average daily feed intake (ADFI) as well as a lower feed-to-gain ratio (F/G) than Group 48 h during the starter period (P < 0.05). Compared with Group 48 h, broilers in Group 2 h exhibited significantly elevated villus height (VH) and villus height to crypt depth ratio (VH: CD) in the duodenum, increased Occludin, and Claudin-1 mRNA expression in the jejunum but decreased crypt depth (CD) in the duodenum at 50 d (P < 0.05). Meanwhile, broilers in Groups 2 h and 24 h had increased glycogen (Gn) and protein (Pro) levels in breast muscle and TG levels in the liver, as well as a higher concentration of serum T3, T4, and IGF-1 compared with Group 48 h at 21 d (P < 0.05). Besides, intestinal microbiota consisted primarily of Firmicutes, Bacteroidetes, and Proteobacteria at the phylum level at 21 d and 50 d; at the genus level, broilers in Group 2 h displayed significantly reduced abundance of Escherichia at 21 d and Bacteroides at 50 d compared with Group 48 h (P < 0.05). Collectively, these findings signal that early post-hatch feeding measures, especially at 21 d, improve hormone secretion, intestinal morphology, and the growth performance of broilers by enhancing intestinal health and modulating the intestinal microbiota.

Effects of posthatch feed deprivation on residual yolk absorption, macronutrients synthesis, and organ development in broiler chicks.

The aim of the research was to evaluate the dynamic changes of early posthatch starvation on residual yolk absorption, synthesis of macronutrients (protein, lipid, and glycogen), and organ development in broiler chicks. A total of 720 1-day-old chicks (Lingnan Yellow) were randomly assigned to 3 treatments: group A (nonfasted), group B (fasting for 24 h after placement), and group C (fasting for 48 h after placement). The trial lasted for 168 h, and water was provided ad libitum all the time. Sampling was performed at 0, 24, 48, 72, 120, and 168 h. Nonfasting (group A) promoted (P < 0.05) the absorption of amino acids, fatty acids, mineral elements, protein, and maternal antibody in the residual yolk of broiler chicks. The concentration of insulin-like growth factor 1 in plasma and the liver was higher (P < 0.05) in group A. Nonfasting enhanced (P < 0.05) the synthesis of protein and glycogen in the breast muscle and liver; the relative weights of the liver, pancreas, and spleen; and body weight, but retarded (P < 0.05) the synthesis of triglyceride in the liver. The results indicated that nonfasting (group A) after placement promoted the absorption of residual yolk and synthesis of protein and glycogen in the breast muscle and liver, whereas early feed deprivation promoted the synthesis of lipid in the liver. Thereby, nonfasting after placement promoted organ development and body growth of broiler chicks.

Curative effects of vancomycin and cefotaxime combined with gamma globulin respectively in neonatal septicemia and their influences on PCT, CRP and hs-CRP.

OBJECTIVE: To explore the curative effects of vancomycin and cefotaxime combined with gamma globulin respectively in neonatal septicemia and their influences on PCT, CRP, and hs-CRP, so as to provide references for clinical treatment. PATIENTS AND METHODS: 181 patients with neonatal septicemia admitted to Huangshi Maternity and Child Health Hospital from April 2012 to August 2014 were selected as the study subjects. Patients treated with vancomycin combined with gamma globulin were selected as group A (96 cases) and those treated with cefotaxime combined with gamma globulin were selected as group B (85 cases). The improvement time of clinical symptoms (milk rejection, nervous system symptoms, body temperature), hospital stays, mortality, medicine curative effects, adverse reactions, complications, and levels of serum CRP, PCT, and hs-CRP of patients before and after treatment were compared between the two groups. RESULTS: The improvement time of clinical symptoms like body temperature, milk rejection, and neurological symptoms, as well as hospital stays in group A were lower than those in group B (p<0.05); the total effective rate of medicine curative effects in group B was better than that in group A (p<0.05); there was no significant difference in levels of serum CRP, PCT, and hs-CRP between the two groups before treatment (p>0.05); after treatment, levels of serum CRP, PCT, and hs-CRP in both groups decreased significantly, and levels of serum CRP, PCT, and hs-CRP in group B decreased more significantly than those in group A (p<0.05). CONCLUSIONS: Cefotaxime combined with gamma globulin in the treatment of patients with neonatal septicemia has short improvement time in clinical symptoms, high total effective rate of drugs, low mortality, fewer adverse reactions and complications, and can significantly reduce levels of serum CRP, PCT, and hs-CRP, which is worthy of further promotion and application in clinical practice.

Association of host genetics with intestinal microbial relevant to body weight in a chicken F2 resource population.

Host-microbiota interactions describe a co-evolution and mutualistic symbiosis. Gut microbial communities are important for diverse host functions. However, in birds, the relationship between the composition of the intestinal microbiota and the genetic variation of the host is not clearly understood. To dissect these interactions, a Chinese yellow broiler line (genetically selected for a high growth rate) and Huiyang Beard chickens (low growth rate) were crossed, generating an F2 population. The population structures of the gut microbes in the phenotypically high and low 91-d body weight individuals of both sexes in the F2 population were studied. Interestingly, a non-metric multidimensional scaling analysis revealed that the microbiota of the high-weight and low-weight females was clearly separated into 2 clusters. A ß-diversity analysis showed that the locus rs16775833 within the doublesex and mab-3-related transcription factor (DMRT) gene cluster accounted for approximately 21% of the variation in the population structure of the gut microbiota. Furthermore, the 2 genetic loci rs15142709 and rs15142674 were significantly associated with specific species of Methanobacterium. These loci are located in the pleiomorphic adenoma gene 1 (PLAG1) and lck/yes-related novel tyrosine kinase (LYN) genes, which are involved in cell differentiation and growth. This finding suggests evidence for the influence of the host genetics on the composition of the gut microbiota in birds and the importance and utility of the host-microbe status to better understand its effect on the potential growth of birds.

Designing of metallic nanocrystals embedded in non-stoichiometric perovskite nanomaterial and its surface-electronic characteristics.

Engineering of novel functional nanocomposite as like as the metallic nanocrystals supported non-stoichiometric perovskite nanomaterial in controlled parameters (size, shape and ratio of chemical characteristics) is a challengeable task. In this context, we present a facile route to fabricate and study its physicochemical property at real time mode in this report. Nanoscale pure Pb crystals surfaced on non-stoichiometric A-site deficient Pb1-xTiO3-y nanoparticle were fabricated when a precursor lead titanate (PbTiO3) nanoparticle was exposed to an electron beam irradiation (EBI) in a transmission electron microscope (TEM) at ambient temperature. In the state of the art, the chemical states and electronic structure of non-irradiated and irradiated PbTiO3 were studied by X-ray photoelectron spectroscopy (XPS). Electron bombardment resulted in a new visible feature at low binding energy in the Pb 4f core level, while Ti 2p and O 1s line shape showed slight changes. The Fermi level of the corresponding materials was determined to be 1.65 ± 0.1 eV and 2.05 ± 0.1 eV above the valence band maximum, respectively. The normal, weakly p-type PTO exhibits peculiar n-type feature after EBI process (The Fermi level moves near to the conduction band). A feasible mechanism is proposed involving the electron-stimulated local bond-breaking phenomenon in PbTiO3.

Gilbert damping in CoFeB/GaAs(001) film with enhanced in-plane uniaxial magnetic anisotropy.

A 3.5 nm amorphous CoFeB film was sputtered on GaAs (001) wafer substrate without applying magnetic field during deposition, and a significant in-plane uniaxial magnetic anisotropy (UMA) field (Hu) of about 300 Oe could be achieved. To precisely determine the intrinsic Gilbert damping constant (α) of this film, both ferromagnetic resonance (FMR) and time-resolved magneto-optical Kerr effect (TRMOKE) techniques were utilized. With good fitting of the dynamic spectra of FMR and TRMOKE, α is calculated to be 0.010 and 0.013, respectively. Obviously, the latter is 30% larger than the former, which is due to the transient heating effect during the TRMOKE measurement. In comparison with ordinary amorphous CoFeB films with negligible magnetic anisotropies, α is enhanced significantly in the CoFeB/GaAs(001) film, which may be mainly resulted from the enhanced spin-orbit coupling induced by the CoFeB/GaAs interface. However, the significant in-plane UMA plays minor role in the enhancement of α.

[Association between hematocrit and risk of incident hypertension: a cohort study].

Objective: To explore the association between hematocrit level and risk of incident hypertension. Method: Subjects who participated at least two times routine health check-up in Health Management Center of Shandong Province Hospital between January 2005 and January 2010 were eligible for inclusion. After excluding participants with known hypertension and other related diseases, a prospective cohort with 20 606 subjects (female: 8 218, male: 12 388) was established. Cox-proportional hazard model was used to assess the association between hematocrit and the development of hypertension for female and male respectively. Results: During the 51 352 person-years of follow-up, newly developed hypertension was confirmed in 3 695 cases. For female, the age-adjusted hazard ratios (95%CI) for incident hypertension were 1.00 (reference), 1.06(0.86-1.29), 1.37(1.14-1.65), 1.60(1.34-1.92), respectively (P for trend<0.000 1) through the 3 quartiles of hematocrit levels.After adjusting multiple factors (age, smoking, drinking habit, physical activity, body mass index(BMI), systolic blood pressure, fasting blood glucose, serum creatinine, high-density lipoprotein, gamma-glutamyl transferase, white blood count), the hazard ratios (95%CI) were 1.00(reference), 1.05(0.85-1.29), 1.25(1.03-1.51), and 1.22(1.00-1.48), respectively (P for trend=0.016 9). For male, the hazard ratio (the highest vs. the lowest hematocrit level) after adjusting age or age and life style factors (smoking, drinking habit, physical activity) was 1.23 (1.11-1.37), 1.21(1.09-1.35), respectively. Other analyses of relationship hematocrit with incident hypertension were not statistically significant in male. Conclusions: Higher hematocrit level is associated with higher risk of incident hypertension, especially in female.

Misfit Strain Relaxation of Ferroelectric PbTiO3/LaAlO3 (111) Thin Film System.

Ferroelectric thin films grown on high index substrates show unusual structural and switching dynamics due to their special strain states. Understanding the misfit relaxation behavior is crucial to facilitate the high index thin film growth with improved quality. In this paper, ferroelectric PbTiO3 thin films were grown on LaAlO3 (111) substrates by pulsed laser deposition technique. The microstructures were investigated by combinations of conventional and aberration-corrected transmission electron microscopy. Diffraction contrast analysis and high resolution imaging reveal that high density interfacial dislocations were distributed at the interfaces. These dislocations have mixed character with Burgers vectors of a <110> and line directions of <112>. The edge components of the dislocations, with the Burgers vectors parallel to the interface, accommodate the lattice mismatch and are the main contributor to the misfit relaxation of this system. The formation mechanism of these dislocations is proposed and discussed to elucidate the novel mismatch relaxation behavior of <111> oriented perovskite films.

Depinning of domain walls in permalloy nanowires with asymmetric notches.

Effective control of the domain wall (DW) motion along the magnetic nanowires is of great importance for fundamental research and potential application in spintronic devices. In this work, a series of permalloy nanowires with an asymmetric notch in the middle were fabricated with only varying the width (d) of the right arm from 200 nm to 1000 nm. The detailed pinning and depinning processes of DWs in these nanowires have been studied by using focused magneto-optic Kerr effect (FMOKE) magnetometer, magnetic force microscopy (MFM) and micromagnetic simulation. The experimental results unambiguously exhibit the presence of a DW pinned at the notch in a typical sample with d equal to 500 nm. At a certain range of 200 nm < d < 500 nm, both the experimental and simulated results show that the DW can maintain or change its chirality randomly during passing through the notch, resulting in two DW depinning fields. Those two depinning fields have opposite d dependences, which may be originated from different potential well/barrier generated by the asymmetric notch with varying d.

Propofol suppresses invasion and induces apoptosis of osteosarcoma cell in vitro via downregulation of TGF-ß1 expression.

OBJECTIVE: Osteosarcoma (OS) is the most common malignant tumor of the bone, with a high mortality rate and poor prognosis. Propofol has been proposed to play a role of antitumor in various cancers. However, the functions and mechanisms of propofol in OS is still not clear. MATERIALS AND METHODS: The different concentrations of propofol were co-incubated with osteosarcoma MG-63 lines for 72 hrs. Cell proliferation, apoptosis, and invasion were detected by MTT assay, Flow cytometry analysis, and Matrigel invasion assay. Western blot was used to detect the TGF-ß1 protein levels. MG-63 cells were treated with human recombinant TGF-ß1 (rh TGF-ß1) to assess the role of TGF-ß1 in propofol-induced anti-tumor activity. RESULTS: Propofol significantly inhibited cell proliferation and invasion and promoted apoptosis of MG-63 lines cells. Propofol also efficiently reduced TGF-ß1 expression. Moreover, restoration of TGF-ß1 by rhTGF-ß1 treatment reversed the effects of propofol on the biological behavior of OS cells. CONCLUSIONS: Propofol can effectively inhibit proliferation and invasion and induce apoptosis of OS cells through, at least partly, downregulation of TGF-ß1 expression.

Atomic mapping of Ruddlesden-Popper faults in transparent conducting BaSnO3-based thin films.

Doped BaSnO3 has arisen many interests recently as one of the promising transparent conducting oxides for future applications. Understanding the microstructural characteristics are crucial for the exploration of relevant devices. In this paper, we investigated the microstructural features of 0.001% La doped BaSnO3 thin film using both conventional and aberration corrected transmission electron microscopes. Contrast analysis shows high densities of Ruddlesden-Popper faults in the film, which are on {100} planes with translational displacements of 1/2a < 111 > . Atomic EELS element mappings reveal that the Ruddlesden-Popper faults are Ba-O layer terminated, and two kinds of kink structures at the Ruddlesden-Popper faults with different element distributions are also demonstrated. Quantitative analysis on lattice distortions of the Ruddlesden-Popper faults illustrates that the local lattice spacing poses a huge increment of 36%, indicating that large strains exist around the Ruddlesden-Popper faults in the film.

Atomic-Scale Interfacial Magnetism in Fe/Graphene Heterojunction.

Successful spin injection into graphene makes it a competitive contender in the race to become a key material for quantum computation, or the spin-operation-based data processing and sensing. Engineering ferromagnetic metal (FM)/graphene heterojunctions is one of the most promising avenues to realise it, however, their interface magnetism remains an open question up to this day. In any proposed FM/graphene spintronic devices, the best opportunity for spin transport could only be achieved where no magnetic dead layer exists at the FM/graphene interface. Here we present a comprehensive study of the epitaxial Fe/graphene interface by means of X-ray magnetic circular dichroism (XMCD) and density functional theory (DFT) calculations. The experiment has been performed using a specially designed FM1/FM2/graphene structure that to a large extent restores the realistic case of the proposed graphene-based transistors. We have quantitatively observed a reduced but still sizable magnetic moments of the epitaxial Fe ML on graphene, which is well resembled by simulations and can be attributed to the strong hybridization between the Fe 3dz2 and the C 2pz orbitals and the sp-orbital-like behavior of the Fe 3d electrons due to the presence of graphene.

Ferroelectrics. Observation of a periodic array of flux-closure quadrants in strained ferroelectric PbTiO3 films.

Nanoscale ferroelectrics are expected to exhibit various exotic domain configurations, such as the full flux-closure pattern that is well known in ferromagnetic materials. Here we observe not only the atomic morphology of the flux-closure quadrant but also a periodic array of flux closures in ferroelectric PbTiO3 films, mediated by tensile strain on a GdScO3 substrate. Using aberration-corrected scanning transmission electron microscopy, we directly visualize an alternating array of clockwise and counterclockwise flux closures, whose periodicity depends on the PbTiO3 film thickness. In the vicinity of the core, the strain is sufficient to rupture the lattice, with strain gradients up to 10(9) per meter. Engineering strain at the nanoscale may facilitate the development of nanoscale ferroelectric devices.

Magnetic interactions in BiFe0.5Mn0.5O3 films and BiFeO3/BiMnO3 superlattices.

The clear understanding of exchange interactions between magnetic ions in substituted BiFeO3 is the prerequisite for the comprehensive studies on magnetic properties. BiFe0.5Mn0.5O3 films and BiFeO3/BiMnO3 superlattices have been fabricated by pulsed laser deposition on (001) SrTiO3 substrates. Using piezoresponse force microscopy (PFM), the ferroelectricity at room temperature has been inferred from the observation of PFM hysteresis loops and electrical writing of ferroelectric domains for both samples. Spin glass behavior has been observed in both samples by temperature dependent magnetization curves and decay of thermo-remnant magnetization with time. The magnetic ordering has been studied by X-ray magnetic circular dichroism measurements, and Fe-O-Mn interaction has been confirmed to be antiferromagnetic (AF). The observed spin glass in BiFe0.5Mn0.5O3 films has been attributed to cluster spin glass due to Mn-rich ferromagnetic (FM) clusters in AF matrix, while spin glass in BiFeO3/BiMnO3 superlattices is due to competition between AF Fe-O-Fe, AF Fe-O-Mn and FM Mn-O-Mn interactions in the well ordered square lattice with two Fe ions in BiFeO3 layer and two Mn ions in BiMnO3 layer at interfaces.