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Cation order, which can be controlled by synthesis conditions and stoichiometry, plays an important role in properties of perovskite materials. Here we show that aliovalent doping by Sb5+ in Sm2MnMn(Mn4−xSbx)O12 quadruple perovskite solid solutions can control cation orders in both A and B sites. Samples with 0.4≤x≤2 were synthesized by a high‐pressure, high‐temperature method at 6 GPa and 1770 K. Three regions with different cation orders were found at 0.5≤x≤1.0, x=1.5–1.6, and x=1.8. The 0.5≤x≤1.0 compositions have a B‐site‐disordered and A‐site columnar‐ordered structure with space group P42/nmc; the x=1.5 and 1.6 samples have a B‐site rock‐salt‐ordered and A‐site columnar‐ordered structure with space group P42/n; the x=1.8 sample has a B‐site rock‐salt‐ordered and A‐site‐disordered structure with space group P21/n. All the samples show one ferrimagnetic transition: TC increases from 35 K to 73 K for 0.5≤x≤1.0, TC=81 K for x=1.5 and 1.6, and TC=53 K for x=1.8. [ABSTRACT FROM AUTHOR]

Cation order, which can be controlled by synthesis conditions and stoichiometry, plays an important role in properties of perovskite materials. Here we show that aliovalent doping by Sb5+ in Sm2MnMn(Mn4−xSbx)O12 quadruple perovskite solid solutions can control cation orders in both A and B sites. Samples with 0.4≤x≤2 were synthesized by a high‐pressure, high‐temperature method at 6 GPa and 1770 K. Three regions with different cation orders were found at 0.5≤x≤1.0, x=1.5–1.6, and x=1.8. The 0.5≤x≤1.0 compositions have a B‐site‐disordered and A‐site columnar‐ordered structure with space group P42/nmc; the x=1.5 and 1.6 samples have a B‐site rock‐salt‐ordered and A‐site columnar‐ordered structure with space group P42/n; the x=1.8 sample has a B‐site rock‐salt‐ordered and A‐site‐disordered structure with space group P21/n. All the samples show one ferrimagnetic transition: TC increases from 35 K to 73 K for 0.5≤x≤1.0, TC=81 K for x=1.5 and 1.6, and TC=53 K for x=1.8. [ABSTRACT FROM AUTHOR]

We show that cation ordering on A site columns, oppositely displaced via coupling to B site octahedral tilts, results in a polar phase of the columnar perovskite (NaY)MnMnTi4O12. This scheme is similar to hybrid improper ferroelectricity found in layered perovskites, and can be considered a realisation of hybrid improper ferroelectricity in columnar perovskites. The cation ordering is controlled by annealing temperature and when present it also polarises the local dipoles associated with pseudo‐Jahn–Teller active Mn2+ ions to establish an additional ferroelectric order out of an otherwise disordered dipolar glass. Below TN≈12 K, Mn2+ spins order, making the columnar perovskites rare systems in which ordered electric and magnetic dipoles may reside on the same transition metal sublattice. [ABSTRACT FROM AUTHOR]

We show that cation ordering on A site columns, oppositely displaced via coupling to B site octahedral tilts, results in a polar phase of the columnar perovskite (NaY)MnMnTi4O12. This scheme is similar to hybrid improper ferroelectricity found in layered perovskites, and can be considered a realisation of hybrid improper ferroelectricity in columnar perovskites. The cation ordering is controlled by annealing temperature and when present it also polarises the local dipoles associated with pseudo‐Jahn–Teller active Mn2+ ions to establish an additional ferroelectric order out of an otherwise disordered dipolar glass. Below TN≈12 K, Mn2+ spins order, making the columnar perovskites rare systems in which ordered electric and magnetic dipoles may reside on the same transition metal sublattice. [ABSTRACT FROM AUTHOR]

The Mycobacterium tuberculosis (MbT) drug resistance remains a serious problem to global public health and usually leads to a lethal outcome in patients with such strain MbT. Precise and rapid identification of a specific MbT strain is vital for the appointment of anti‐tuberculosis therapy. We continue investigation of deactivated MbT strains of the Beijing family by Raman spectroscopy method and focus on glutathione (GSH) as a potential biomarker for strains identification. Strains under the study have different drug sensitivity: sensitive, multi, and extensively drug resistant. Samples were investigated by Raman spectrometry with He‐Ne (633 nm) laser excitation source in the "fingerprint" region. As a result, GSH vibrational bands for potential strain discrimination were determined. These differences can be described for drug‐sensitive and drug‐resistant strains taken of pulmonary and extra‐pulmonary forms of tuberculosis. We suppose that the obtained results can be useful for new diagnostic tools development for identification of different MbT strains in clinical medicine and research practice. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to evaluate the Hemoclot Quanti. V‐L assay in various clinical conditions. Methods: We compared the Hemoclot Quanti.V‐L assay with DNA testing and with the Pefakit assay in 60 normal (no mutation) vs carriers of the factor V (FV) Leiden mutation (56 heterozygous and three homozygous). We further investigated the interference of lupus anticoagulant on test results in normal and heterozygous individuals and of direct oral anticoagulants (DOACs) at trough and peak levels. Additionally, DOAC‐Remove was tested in samples containing DOACs at peak levels. We further evaluated the influence of FV deficiency on this quantitative assay. Results: There was a 100% agreement between the Quant. V‐L assay and DNA testing in 60 normal individuals. However, 1.85% of heterozygous and 33% of homozygous samples were falsely classified with the quantitative assay, and no misclassification was observed with the Pefakit assay. Lupus anticoagulant did not influence the test results of the quantitative assay. DOACs also interfered with test results in heterozygous patients, but this effect was prevented with the DOAC‐Remove procedure. Even mild FV deficiency affected the test results of the quantitative assay in heterozygous patients leading either to misclassification or the need for subsequent PCR testing. Conclusion: The quantitative FV‐L assay has several limitations, especially FV deficiency and the presence of DOACs have to be ruled out before running this quantitative assay. [ABSTRACT FROM AUTHOR]

Artificial placenta (AP) technology aims to maintain fetal circulation, while promoting the physiologic development of organs. Recent reports of experiments performed in sheep indicate the intrauterine environment can be recreated through the cannulation of umbilical vessels, replacement of the placenta with a low‐resistance membrane oxygenator, and incubation of the fetus in fluid. However, it remains to be seen whether animal fetuses similar in size to the extremely preterm human infant that have been proposed as a potential target for this technology can be supported in this way. Preterm Yucatan miniature piglets are similar in size to extremely preterm human infants and share similar umbilical cord anatomy, raising the possibility to serve as a good model to investigate the AP. To characterize fetal cardiovascular physiology, the carotid artery (n = 24) was cannulated in utero and umbilical vein (UV) and umbilical artery were sampled. Fetal UV flow was measured by MRI (n = 16). Piglets were delivered at 98 ± 4 days gestation (term = 115 days), cannulated, and supported on the AP (n = 12) for 684 ± 228 min (range 195–3077 min). UV flow was subphysiologic (p =.002), while heart rate was elevated on the AP compared with in utero controls (p =.0007). We observed an inverse relationship between heart rate and UV flow (r2 =.4527; p <.001) with progressive right ventricular enlargement that was associated with reduced contractility and ultimately hydrops and circulatory collapse. We attribute this to excessive afterload imposed by supraphysiologic circuit resistance and augmented sympathetic activity. We conclude that short‐term support of the preterm piglet on the AP is feasible, although we have not been able to attain normal fetal physiology. In the future, we propose to investigate the feasibility of an AP circuit that incorporates a centrifugal pump in our miniature pig model. [ABSTRACT FROM AUTHOR]

Preterm infants are at high risk for developing bronchopulmonary dysplasia and pulmonary hypertension from inflammatory lung injury. In adult models, adiponectin (APN)—an adipocyte‐derived hormone—protects the lung from inflammatory injury and pulmonary vascular remodeling. Cord blood APN levels in premature infants born < 26 weeks gestation are 5% of the level in infants born at term. We previously reported the expression profile of APN and its receptors in neonatal rat lung homogenates during the first 3 weeks of postnatal development. Here, we characterize the expression profile of APN and its receptors in specific lung cells and the effects of exogenous recombinant APN (rAPN) on lipopolysaccharide‐(LPS)‐induced cytokine and chemokine production in total lung homogenates and specific lung cells. In vitro, rAPN added to primary cultures of pulmonary artery smooth muscle cells attenuated the expression of LPS‐induced pro‐inflammatory cytokines while increasing the expression of anti‐inflammatory cytokines. In vivo, intraperitoneal rAPN (2 mg/kg), given 4 hr prior to intrapharyngeal administration of LPS (5 mg/kg) to newborn rats at postnatal day 4, significantly reduced gene and protein expression of the pro‐inflammatory cytokine IL‐1ß and reduced protein expression of the chemokines monocyte chemoattractant protein (MCP‐1) and macrophage inflammatory protein‐1 alpha (MIP‐1α) in the lung. LPS‐induced histopathological changes in the lung were also decreased. Moreover, rAPN given 20 hr after intrapharyngeal LPS had a similar effect on lung inflammation. These findings suggest a role for APN in protecting the lung from inflammation during early stages of lung development. [ABSTRACT FROM AUTHOR]

Background: Haemolysis, lipaemia and hyperbilirubinaemia represent important challenges in the coagulation laboratory. Test results are influenced not only by the degree of the interfering substance but also by the detection system. Methods: We investigated the interference of free haemoglobin, triglycerides and bilirubin on a "modified activated protein C (APC) resistance test," protein C activity and protein S (antigen and activity) with two coagulation analysers, the STA‐R Evolution and the ACL TOP. Results: Haemolysis interfered with all assays on the STA‐R Evolution resulting in higher levels of protein C activity and lower levels of protein S and a decreased APC ratio compared with baseline levels. On the ACL TOP, haemolysis only diminished protein S antigen levels and the APC ratio. Lipaemia increased protein C activity and protein S activity levels on the STA‐R Evolution, whereas APC‐R decreased on the ACL TOP and protein S antigen could not be measured in any lipaemic samples. Hyperbilirubinaemia caused an increase in protein C activity and in protein S antigen and a decrease in APC‐R on the STA‐R Evolution, whereas a decline of protein C activity, of protein S antigen and of the APC‐R could be observed in icteric samples on the ACL TOP. Conclusions: Our data show that the degree of interference associated with haemolysis, lipaemia and hyperbilirubinaemia is different in several assays. Some assay limitations were not reproduced, and limitations stated in kit inserts cannot be assumed to apply to all analysers. [ABSTRACT FROM AUTHOR]

Abstract: Solid solution of Ca9‐xMgxBi(VO4)7 in powder and ceramic forms are obtained by solid‐state reactions. Details of their crystal structures are determined for x = 0.25 and x = 0.5 by synchrotron radiation diffraction and the Rietveld method. The refinement has confirmed that Mg2+ is replacing Ca2+ in M5 position of a polar (S.G. R3c) β‐Ca3(PO4)2‐type structure. Thermal analysis, dielectric and second harmonic generation experiments in broad temperature regions have proved this polar structure is formed for 0 ≤ x ≤ 0.7. Magnesium for calcium substitution enhances optical nonlinear activity of Ca9‐xMgxBi(VO4)7 in 0 < x ≤ 0.5. Two phase transitions have been found, one of which from polar to centrosymmetric phase is accompanied by dielectric constant peak of ferroelectric type. The other is upper on temperature, marked with smaller dielectric anomaly, and goes between 2 centrosymmetric phases. Temperatures of the phase transition only slightly depend on x, the first being near 1050 K, the second near 1100 K. Electric conductivity quickly rises with temperature in the polar phase. At higher temperature it changes according to the Arrhenius law with small activation energy, Ea ~ 0.7 eV for bulk conductivity and Egb ~ 2.0‐2.5 eV for grain boundary conductivity. The analysis of bulk and grain boundary conductivities agrees with Ca2+‐ion fast transport in ceramics. The bulk conductivity slowly decreases with magnesium content, the grain boundary conductivity does not notably depend on the composition. [ABSTRACT FROM AUTHOR]

Abstract: Background: Gastric residuals are a common finding in enterally fed preterm neonates and traditionally thought to reflect immaturity‐related delayed gastric emptying. Adult human data suggest that the meal volume regulate the gastric emptying rate, but early in life, this has not been adequately evaluated. The goal of this study was to study the rat postnatal changes in gastric emptying rate and the strain‐induced effect on muscle contraction. We hypothesized that the stomach content volume and not developmental factors determines the newborn gastric emptying rate, via the Rho‐kinase 2 (ROCK‐2) pathway. Methods: Gastric volume and emptying rate measurements were obtained by ultrasound at different postprandial times and the wall strain‐dependent changes in muscle contraction were evaluated ex vivo. Key Results: The newborn rat gastric emptying rate was unrelated to postnatal age, maximal 30 min postprandial, and directly proportional to content volume. In vitro measurements showed that the agonist‐induced gastric muscle contraction was directly proportional to the stomach wall strain. These changes were mediated via upregulation of ROCK‐2 activity. Conclusions & Inferences: The newborn rat gastric emptying rate is not developmentally regulated, but dependent on the content volume via wall strain‐induced ROCK‐2 activation. Further clinical studies addressing the content volume effect on the rate of gastric emptying are warranted, to enhance feeding tolerance in preterm neonates. [ABSTRACT FROM AUTHOR]

The specific morphology and magnetic properties of magnetite-based glass-ceramics obtained by crystallization of Fe-containing borosilicate glassmelts in the presence of P2O5 as nucleating agent are investigated. We found that the distribution of the tiny nanoparticles of magnetite determines the low temperature response to magnetic field. The observed effects are discussed with respect to the following factors: (1) the existence of a multimodal size distribution of the tiny grains as revealed by Mössbauer spectroscopy, magnetometry, and high-resolution electron microscopy; (2) the existence of a disordered layer at the grain surface which is driven by field in a magnetically ordered state; and (3) the interplay between the relaxation mechanisms in different temperature ranges. [ABSTRACT FROM AUTHOR]

The oxygen nonstoichiometry of large oxygen-deficient Ruddlesden-Popper oxides LaxSr3-xFe2O7-δ (LSFO7-x) (x = 0, 0.25, 0.5) was measured by the high-temperature gravimetry and the coulometric titration. In the composition series, the P(O2) dependencies exhibited typical plateaus at δ = (2-[La·Sr])/2. Meanwhile, La0.5Sr2.5Fe2O7-δ showed the smallest oxygen nonstoichiometry and was the most thermochemically stable compound against P(O2), temperature, and the La content. Based on the defect equilibrium model and the statistical thermodynamic calculation derived oxygen nonstoichiometric data, the substitution of La for Sr-site can promote the forward reaction of oxygen incorporation, the backward reaction of the disproportionation of the charge carriers, and oxygen redistribution between the O1 and O3 sites, resulting in the reduction of oxygen-deficient and the lower decomposition P(O2). The obtained thermodynamic quantities of the partial molar enthalpy of oxygen, hO - h°O, and the partial molar entropy of oxygen, sO - s°O, calculated from the statistical thermodynamic calculation are in good agreement with those using the Gibbs-Helmholtz equation. [ABSTRACT FROM AUTHOR]

The synthesis of a novel family of cyano-bridged trimetallic coordination polymers (CPs) with various compositions and shapes has been reported by changing the compositional ratios of Fe, Co, and Ni species in the reaction system. In order to efficiently control the nucleation rate and the crystal growth, trisodium citrate dihydrate plays an important role as a chelating agent. After the obtained cyano-bridged trimetallic CPs undergo thermal treatment in air at three different temperatures (250, 350, and 450 °C), nanoporous spinel metal oxides are successfully obtained. Interestingly, the obtained nanoporous metal oxides are composed of small crstalline grains, and the grains are oriented in the same direction, realizing pseudo-single crystals with nanopores. The resultant nanoporous spinel oxides feature interesting magnetic properties. Cyano-bridged multimetallic CPs with various sizes and shapes can provide a pathway toward functional nanoporous metal oxides that are not attainable from simple cyano-bridged CPs containing single metal ions. [ABSTRACT FROM AUTHOR]

We report a novel strategy to improve the dielectric properties of the biferroic YCrO3 ceramic compound through interface conduction control by means of an insulating Al2O3 using a core-shell design. The YCrO3 particles were covered with several layers of insulating Al2O3 using the atomic layer deposition technique to produce the core-shell structure. TEM images reveal homogeneous and well-defined Al2O3 coatings of ~8, ~60, and ~130 nm thickness. XRD shows the Al2O3-shell to be amorphous. The dielectric characteristics of the sintered nanocomposite were investigated in the 100 Hz-1 MHz frequency range and temperature between 300 and 580 K. As the Al2O3- shell thickness covering the YCrO3 particles is increased, a decrease of the dielectric permittivity, loss tangent and AC conductivity values was found in the whole range of temperatures and frequencies. Furthermore, the rounded hysteresis loop, typical of conductive ceramic is restored as the insulating Al2O3 layer becomes thicker. This behavior is explained because the insulating Al2O3-shell acts as internal barrier layer localizing the surface charges on the sintered grain boundaries. This fact was confirmed by Electron Beam Induced Current technique where a clear contrast at the grain boundaries confirms the charge localization at the YCrO3/Al2O3 interface. These results also reveal that the Al2O3-shell induces another conductive mechanism when the insulating Al2O3 layer becomes thicker. Nonetheless, this new strategy is an effective approach to suppress the parasitic conductivity in polycrystalline multiferroic ceramics and increasing thus the multifuncionality. [ABSTRACT FROM AUTHOR]

Different from the homogeneous layer structure of famous Bi n+1Fe n−3Ti3O3 n+3 compounds with integer n values, the mixed-layer structure of the compounds with fractional n values and their related physics have been rarely reported in recent years. In this work, the mixed-layer compound Bi11Fe3Ti6O33 ( n = 4.5) was synthesized by the modified Pechini method, and its structure was characterized as an inhomogeneous phase generating from the disordered intergrowths of the n = 4 and 5 perovskite slabs. Multiferroic properties of this compound were discussed in detail, compared with two adjacent homologous Aurivillius phases Bi5FeTi3O15 ( n = 4) and Bi6Fe2Ti3O18 ( n = 5). Significantly, the ferroelectric polarization of the mixed-layer sample at room temperature is higher than that of the adjacent homologous phases with integer n, mainly arising from the intrinsic mixed-layer structure. The ferroelectric Curie temperature (~992 K) and a magnetic transition temperature (~7 K) of the 4.5-layer phase of Bi11Fe3Ti6O33 fall in between those of the homogeneous 4- and 5-layer phases, conforming to the change trends of such oxides with integer n. These results provide important contributions to understand the Aurivillius-type materials and open up a new avenue to enhance multiferroic properties in single-phase multiferroics. [ABSTRACT FROM AUTHOR]

The electrical properties of polycrystalline NiZn ferrite, Zn0.44Ni0.38Fe2.18O4, were investigated by impedance spectroscopy over the frequency and temperature ranges, 5 Hz to 2 MHz and 10-600 K and by magnetic permeability measurements at room temperature. Samples were sintered in either conventional or solar furnaces followed by quenching or slow cooling to ambient temperature. Depending on processing conditions, the room-temperature electrical resistivity of conventionally sintered samples varied by seven orders of magnitude, from 5 ohm cm for a sample quenched from 1250°C to 10 Mohm cm for a sample quenched from 400°C. These differences were attributed to variations in oxygen content of the ferrite which decreased with increasing quench temperature. Oxygen deficiency led to mixed valence of Fe in the octahedral B sites of the spinel structure and was responsible for high electronic conductivity with low activation energy at low temperatures in oxygen-deficient samples. By contrast, in oxygen-stoichiometric samples, Fe on the tetrahedral A sites was believed to be divalent and Fe on the octahedral B sites to be entirely trivalent. Electron hopping between A and B sites had much higher activation energy and dominated the conductivity at high temperature for all samples. Samples sintered in the solar furnace were much more conductive than ones that were slow-cooled after conventional sintering and this is attributed to the relatively rapid cooling rate after exposure in the solar furnace, which preserved some of the oxygen deficiency present at high temperature. For the same reason, samples that were slow cooled in N2 were also much more conductive. Solar-sintered samples with higher density (96%) had higher real permeability than slow-cooled, conventionally sintered ones (86%) mainly due to a combination of their lower resistivity and higher density. Resistivity seems to have a greater correlation with the imaginary permeability than density has. [ABSTRACT FROM AUTHOR]

Ferrite-based, hard-soft magnetic nanocomposites with the composition (100%− x)SrFe12O19- xCoFe2O4, where x = 5, 10, and 15 wt%, were prepared by mixing the constituent powders, followed by spark plasma sintering. In order to control the particle size of the constituent materials, the SrFe12O19 and CoFe2O4 powders were synthesized using the hydrothermal method, mixed and then consolidated with spark plasma sintering. The conditions during the spark plasma sintering process (sintering temperature, time, and applied pressure) were varied in order to prepare composites with a high density and exchange-coupled hard and soft magnetic phases, leading to an increase in the maximum energy product, when compared with pure SrFe12O19. The microstructural analysis revealed that the relative density of the sintered composite exceeded 90% of the theoretical value and that the CoFe2O4 was uniformly distributed in the SrFe12O19 matrix. Magnetic measurements of the sintered composites showed a single-phase magnetic behavior. When compared with the single-phase SrFe12O19 used in this study, the SPS composites exhibited a 22% increase in the maximum energy product (26.1 kJ/m3). [ABSTRACT FROM AUTHOR]

In-plane c-axis oriented Ba-hexaferrite (BaM) thin films were prepared on a-plane sapphire (Al2O3) substrates using direct current ( DC) magnetron sputtering followed by ex-situ annealing. The sputtering atmosphere was found to have a great influence on the stoichiometry, orientation growth, and grain morphology of the as-prepared BaM films. With moderate oxygen partial pressure during sputtering, in-plane c-axis highly oriented BaM films were obtained. The films showed strong magnetic anisotropy with a high hysteresis loop squareness ( Mr/ Ms of 0.96) along in-plane easy axis and a low Mr/ Ms of 0.05 along in-plane hard axis. Rocking curves and pole figures were utilized to reveal the epitaxial-like orientation relationship of the BaM films relative to the sapphire substrates, as well as the orientation growth dispersion of the hexagonal platelet-shaped grains in BaM films. [ABSTRACT FROM AUTHOR]

A perovskite-like layer-structured compound, Ce2Ti2O7, was prepared in the argon atmosphere using solid reaction process. Single phase and dense Ce2Ti2O7 ceramic was fabricated by high-pressure sintering at 4 GPa and 1100°C. This compound is unstable in oxygen/air when temperature is above 400°C, but it is stable under argon/vacuum. Differential scanning calorimetry result shown Ce2Ti2O7 has a phase transition at 1073°C, which might be the Curie point. The ferroelectricity of Ce2Ti2O7 was confirmed by the piezoelectric activity after poling (d33 = 0.4 ± 0.2 pC/N) for the first time. [ABSTRACT FROM AUTHOR]

We investigate the effect of slight Ti substitution (≤0.5%) for Cr in CuCr1− xTi xO2 by measuring the structural, magnetic, and electrical transport properties. Upon Ti doping, the antiferromagnetic transition becomes blurred without a change in Néel temperature. Ti4+ substituting to Cr3+ site is found to significantly enhance the resistivity due to the diminishing conducting holes. We find strong time-dependent electrical transport behavior in CuCr1− xTi xO2 induced by slight Ti doping. The key observation is that a metastable behavior occurs in Ti-doped CuCr1− xTi xO2. A strong resistive relaxation ( RR) behavior occurs in Ti-doped CuCr1− xTi xO2 with its magnitude remarkably increasing with increasing Ti content, while it is absent in undoped CuCrO2. The RR is found to be described by the combination of an exponential function and a logarithmic dependence at long time. The relaxation behavior in CuCr1− xTi xO2 is found to show a correlation with the local lattice deformation. [ABSTRACT FROM AUTHOR]

New nanoporous iron oxide nanoparticles with superparamagnetic behavior were successfully synthesized from Prussian blue (PB) nanocubes through a thermal conversion method and applied to the intracellular drug-delivery systems (DDS) of bladder cancer cells (i.e., T24) with controlled release and magnetic guiding properties. The results of the MTT assay and confocal laser scanning microscopy indicate that the synthesized iron oxide nanoparticles were successfully uptaken by T24 cells with excellent biocompatibility. An anticancer drug, that is, cisplatin, was used as a model drug, and its loading/release behavior was investigated. The intracellular drug delivery efficiency was greatly enhanced for the cisplatin-loaded, PB-derived, magnetic-guided drug-delivery system compared with the non-drug case. The synthesized nanomaterials show great potential as drug vehicles with high biocompatibility, controlled release, and magnetic targeting features for future intracellular DDS. [ABSTRACT FROM AUTHOR]

We investigated the effect of annealing temperature on magnetic properties of 2% and 10% Fe-doped BaTiO3. To understand the possible structural differences between samples treated at different annealing temperatures, and to correlate them with the magnetic properties, several characterization techniques, such as X-ray diffraction and X-ray absorption spectroscopic methods ( XANES and EXAFS) were employed. We found that the 2% Fe-doped BaTiO3 pseudocubic perovskite is paramagnetic regardless of the heat-treatment conditions. Initially paramagnetic 10% Fe-doped 6H-BaTiO3, treated at 1250°C, became ferromagnetic after additional annealing at higher temperature. We have crystalographically characterized the cation ordering processes in the 6H-BaTiO3 that occurred during the high-temperature annealing. The ferromagnetism that is induced in this stage is most probably associated with the observed diffusion processes but it extrinsic character still cannot be fully disregarded. [ABSTRACT FROM AUTHOR]

In this letter, 2-μm Pb0.97La0.02(Zr0.75Sn0.18Ti0.07)O3 antiferroelectric thick film with tetragonal structure was prepared. The effects of operating electric field, temperature, and frequency on the thermal-electrical energy harvesting capacity of the film were studied by using the Olsen cycle. The results demonstrated that giant energy harvesting effect could be realized in the antiferroelectric thick film. The maximum harvestable energy density per cycle of the film was about 7.8 J/cm3 at 1 kHz, which was the largest reported value to date. The corresponding energy harvesting efficiency was 0.53%. Moreover, the film had a low leakage current density (about 7.3 × 10−7 and 3.9 × 10−5 A/cm2 at 25 and 200°C, respectively), which was favorable for its application in the devices of the thermal-electrical energy harvesting. [ABSTRACT FROM AUTHOR]

Electrospinning provides a promising route to quickly produce high-purity ceramic fibers from readily available sol-gel precursors. Recently, techniques have been developed to enable the production of biphasic nanocomposites on a single fiber, enabling the development of novel composites with connectivities that are difficult to obtain using existing methods. These 'composites on a fiber' can be used as a unique anisotropic building block for creating more complex ordered structures. This work examines links between processing, structure, and properties for Janus-type composite nanofibers for the magnetoelectric BaTiO3- CoFe2 O4 system. Specifically, we show how altering the viscosity and conductivity of precursor solutions can provide a unique route to synthesize biphasic composites of a range of sizes and compositions. Furthermore, we show how altering these properties can impact the magnetic and magnetoelectric behavior of these fibers. While this work focuses specifically on the BaTiO3- CoFe2 O4 system, lessons learned can be applied to electrospinning biphasic ceramic materials from a variety of material systems and applications. [ABSTRACT FROM AUTHOR]

Development of a new method to synthesize nanoporous metal oxides with highly crystallized frameworks is of great interest because of their wide use in practical applications. Here we demonstrate a thermal decomposition of metal-cyanide hybrid coordination polymers (CPs) to prepare nanoporous metal oxides. During the thermal treatment, the organic units (carbon and nitrogen) are completely removed, and only metal contents are retained to prepare nanoporous metal oxides. The original nanocube shapes are well-retained even after the thermal treatment. When both Fe and Co atoms are contained in the precursors, nanoporous FeCo oxide with a highly oriented crystalline framework is obtained. On the other hand, when nanoporous Co oxide and Fe oxide are obtained from Co- and Fe-contacting precursors, their frameworks are amorphous and/or poorly crystallized. Single-crystal-like nanoporous FeCo oxide shows a stable magnetic property at room temperature compared to poly-crystalline metal oxides. We further extend this concept to prepare nanoporous metal oxides with hollow interiors. Core-shell heterostructures consisting of different metal-cyanide hybrid CPs are prepared first. Then the cores are dissolved by chemical etching using a hydrochloric acid solution (i.e., the cores are used as sacrificial templates), leading to the formation of hollow interiors in the nanocubes. These hollow nanocubes are also successfully converted to nanoporous metal oxides with hollow interiors by thermal treatment. The present approach is entirely different from the surfactant-templating approaches that traditionally have been utilized for the preparation of mesoporous metal oxides. We believe the present work proves a new way to synthesize nanoporous metal oxides with controlled crystalline frameworks and architectures. [ABSTRACT FROM AUTHOR]

Eu2+ and Mn2+ coactivated β- Ca3( PO4)2 ( TCP) phosphors have been prepared by high-temperature solid-state reaction. The site occupation and photoluminescence properties of Eu2+ and Mn2+ have been identified and discussed in detail. The energy transfer from Eu2+ to Mn2+ in TCP: Eu2+, Mn2+ phosphors has been validated and demonstrated to be a resonant type via a dipole-quadrupole mechanism, and the critical distance ( R C) calculated by concentration quenching method is 21.76 Å. A color-tunable emission from violet-blue to red in TCP: Eu2+, Mn2+ phosphors can be realized via the energy transfer from Eu2+ to Mn2+ ions. [ABSTRACT FROM AUTHOR]

In situ observations of ferroelectric domain structure evolution, and magnetoelectric (ME) coupling are investigated for PMN-28PT/Terfenol-D (abbreviation of Pb( Mg1/3 Nb2/3) O3-28 PbTiO3/ Tb0.3 Dy0.7 Fe2) and PMN-33PT/Terfenol-D composites under the magnetic loadings. The composite of PMN-33PT/Terfenol-D shows stronger ME coupling than that in PMN-28PT/Terfenol-D. At a thickness of 0.10-0.12 mm for the single crystal plate, a giant magnetoelectric coefficient (αME) up to 2 V/cm·Oe is obtained for PMN-33PT/Terfenol-D at a static magnetic field of 200 Oe and 1 kHz of the alternating magnetic field. In situ domain structure observations reveal the domain morphology change during the applied magnetic loadings. In PMN-28PT, the domains are of predominantly rhombohedral ( R) phase and they change into monoclinic MA phase upon the magnetic loading via the strain transferred between Terfenol-D plate and PMN-PT single crystal. In PMN-33PT, domains of orthorhombic ( O), R, and monoclinic MC coexist and phase transitions from O to MC and further to R phase occur upon the magnetic loading. The undulation and diversity of the domain structure makes the domains more susceptible to the magnetic loading via strain transferred between Terfenol-D plate and PMN-PT single crystal, and consequently, a strong ME coupling in the composites. [ABSTRACT FROM AUTHOR]

Regional pulmonary blood flow can be assessed using both dynamic contrast-enhanced (DCE) MR and phase-contrast (PC) MR. These methods provide somewhat complementary information: DCE MR can assess flow over the entire lung while PC MR can detect rapid changes in flow to a targeted region. Although both methods are considered accurate, one may be more feasible than the other depending on pathology, patient condition, and availability of an intravenous route. The objective of this study was to establish a consensus between the two methods by comparing paired DCE MR and PC MR measurements of relative blood flow in Yorkshire piglets ( N = 5, age = 7 days, weight = 3.3 ± 0.6 kg) under various physiological states including regional lung collapse. A strong correlation (R2 = 0.71, P < 0.01) was observed between the methods. In conclusion, DCE MR and PC MR provide a consistent measure of changes in regional pulmonary blood flow. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Purpose: To determine the association between cancer diagnosis, mental disorders and suicidal behavior among community dwelling adults. Methods: Data were drawn from the nationally representative Canadian Community Health Survey Cycle 1.2 (N=36 984, response rate 77%, age 15+). Respondents were grouped into three age groups (15–54, 55–74, and 75+ years), and multiple regression analyses were conducted to examine the relationship between cancer and mental disorders: unadjusted and adjusted for sociodemographics, social supports and other mental disorders. Results: Among respondents aged 15–54, cancer was associated with increased odds of major depression (odds ratio [OR]=3.18; 95% confidence interval [CI]: 1.69–5.96), panic attacks (OR=2.15; 95% CI: 1.22–3.77) and any mental disorder. Among respondents aged 55–75, cancer was associated with increased odds of agoraphobia (OR=5.94; 95% CI: 1.68–21.03) and decreased odds of social phobia (OR=0.22; 95% CI: 0.06–0.80). Cancer was not associated with any mental disorder in the 75+ age group. Results persisted after adjustments for the covariates. Suicidal ideation was associated with cancer in the 55–74 age group (OR=5.07; 95% CI: 1.25–20.47) in unadjusted models; however, this relationship became non-significant when adjusting for the other covariates. Conclusion: Clinicians should consider screening for depression and panic disorder in young, community dwelling patients with cancer. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

OC01.05: Feasibility of the short-term physiologic support of the late-gestation miniature pig fetus using umbilical cannulation, a pumpless extreacorporeal membrane oxygenator and fluid incubation To support the late-gestation miniature pig fetus using an artificial placenta system for a minimum of four hours using in utero physiologic umbilical flow and blood gas measurements for reference. Umbilical vein blood flow was measured in utero using high-resolution cine phase contrast MRI according to our previously published technique using a 3-Tesla MRI system (Siemens PrismaFit, Erlangen);. [Extracted from the article]