Red Y2O3:Eu-Based Electroluminescent Device Prepared by Atomic Layer Deposition for Transparent Display Applications

Y₂O_3:Eu is a promising red-emitting phosphor owing to its high luminance efficiency, chemical stability, and non-toxicity. Although Y₂O₃:Eu thin films can be prepared by various deposition methods, most of them require high processing temperatures in order to obtain a crystalline structure. In this work, we report on the fabrication of red Y₂O₃:Eu thin film phosphors and multilayer structure Y₂O₃:Eu-based electroluminescent devices by atomic layer deposition at 300 °C. The structural and optical properties of the phosphor films were investigated using X-ray diffraction and photoluminescence measurements, respectively, whereas the performance of the fabricated device was evaluated using electroluminescence measurements. X-ray diffraction measurements show a polycrystalline structure of the films whereas photoluminescence shows emission above 570 nm. Red electroluminescent devices with a luminance up to 40 cd/m² at a driving frequency of 1 kHz and an efficiency of 0.28 Lm/W were achieved.     

Quantitative Assessment of Myocardial Perfusion in the Detection of Significant Coronary Artery Disease : Cutoff Values and Diagnostic Accuracy of Quantitative [O]H2O PET Imaging

Background

Recent studies have demonstrated improved diagnostic accuracy for detecting coronary artery disease (CAD) when myocardial blood flow (MBF) is quantified in absolute terms, but there are no uniformly accepted cutoff values for hemodynamically significant CAD.

Objectives

The goal of this study was to determine cutoff values for absolute MBF and to evaluate the diagnostic accuracy of quantitative [¹⁵O]H₂O positron emission tomography (PET).

Methods

A total of 330 patients underwent both quantitative [¹⁵O]H₂O PET imaging and invasive coronary angiography in conjunction with fractional flow reserve measurements. A stenosis >90% and/or fractional flow reserve ≤0.80 was considered obstructive; a stenosis <30% and/or fractional flow reserve >0.80 was nonobstructive.

Results

Hemodynamically significant CAD was diagnosed in 116 (41%) of 281 patients who fulfilled study criteria for CAD. Resting perfusion was 1.00 ± 0.25 and 0.92 ± 0.23 ml/min/g in regions supplied by nonstenotic and significantly stenosed vessels, respectively (p < 0.001). During stress, perfusion increased to 3.26 ± 1.04 ml/min/g and 1.73 ± 0.67 ml/min/g, respectively (p < 0.001). The optimal cutoff values were 2.3 and 2.5 for hyperemic MBF and myocardial flow reserve, respectively. For MBF, these cutoff values showed a sensitivity, specificity, and accuracy for detecting significant CAD of 89%, 84%, and 86%, respectively, at a per-patient level and 87%, 85%, and 85% at a per-vessel level. The corresponding myocardial flow reserve values were 86%, 72%, and 78% (per patient) and 80%, 82%, and 81% (per vessel). Age and sex significantly affected diagnostic accuracy of quantitative PET.

Conclusions

Quantitative MBF measurements with the use of [¹⁵O]H₂O PET provided high diagnostic performance, but both sex and age should be taken into account.     

Submicron fibers as a morphological improvement of amorphous zirconium oxide particles and their utilization in antimonate (Sb(v)) removal

Mesoporous and large surface area zirconium oxide aggregate granules with good adsorption properties were synthesized using a simple precipitation method. Since utilization of these small and fragile particles is considered rather difficult in larger scale column operation, the product was formed into a fibrous form to improve its usability. The submicron fibers were obtained from an optimized electroblowing synthesis that resulted in elastic and uniform fibers with a tetragonal structure and high length-to-diameter ratio. In antimonate (Sb(v)) adsorption experiments, the higher calcination temperature (350 °C) of the fibers did not seem to decrease the Sb(v) adsorption capacity excessively since the high theoretical adsorption capacities were 113 mg g⁻¹ and 58 mg g⁻¹ for the aggregate and fibers, respectively. Both materials had fast kinetics, fibers being faster in the beginning of the reaction. Moreover, both materials offered efficient Sb(v) removal in the studied pH range from 1 to 11 by reaching over 99.9% adsorption in the optimal pH range. X-ray absorption near edge spectroscopy (XANES) revealed that Sb(v) stays as pentavalent antimony after being adsorbed by these materials and based on the isoelectric point shifts in the zeta potential measurement, adsorption occurs mainly by an inner-sphere complexation reaction. Finally, our study showed that pressure buildup in a flow-through column packed with zirconium oxide fibers was significantly lower than in a column packed with aggregates. Thus, zirconium oxide aggregates can be formed into submicron fibers with enhanced column operation properties without a too large compromise in the adsorption properties.

Zirconium oxide was formed into submicron fibers to improve the Sb(v) separation performance compared to a conventional aggregate material.     

Increasing circulating levels of Tenascin C in response to the Wingate anaerobic test

Aim

Tenascin C (TNC) is a large extracellular matrix glycoprotein. It is involved in development and upregulated both during tissue repair and in several pathological conditions, including cardiovascular disease. Extracellular matrix proteins play a role in promoting exercise responses, leading to adaptation, regeneration, and repair. The main goal of this study was to investigate whether a short anaerobic effort leads to increased levels of TNC in serum.

Methods

Thirty-nine healthy men performed a Wingate test followed by a muscle biopsy. Myoblasts were isolated from the muscle biopsies and differentiated to myotubes ex vivo. TNC RNA was quantified in the biopsies, myotubes and myoblasts using RNA sequencing. Blood samples were drawn before and 5 min after the Wingate test. Serum TNC levels were measured using enzyme-linked immunosorbent assay.

Results

After the Wingate test, serum TNC increased on average by 23% [15–33], median [interquartile range]; P_Wilcoxon < 0.0001. This increase is correlated with peak power output and power drop, but not with VO_2max. TNC RNA expression is higher in myoblasts and myotubes compared to skeletal muscle tissue.

Conclusion

TNC is secreted systemically as a response to the Wingate anaerobic test in healthy males. The response was positively correlated with peak power and power drop, but not with VO_2max which implicates a relation to mechanical strain and/or blood flow. With higher expression in undifferentiated myoblast cells than muscle tissue, it is likely that TNC plays a role in muscle tissue remodelling in humans. Our findings open for research on how TNC contributes to exercise adaptation.     

Theiler’s virus infection provokes the overexpression of genes coding for the chemokine Ip10 (CXCL10) in SJL/J murine astrocytes,which can be inhibited by modulators of estrogen receptors

Theiler’s murine encephalomyelitis virus (TMEV) induces demyelination in susceptible strains of mice (SJL/J) through an immunopathological process that is mediated by CD4⁺ Th1 T cell. These T cells are chemoattracted to the central nervous system by chemokines. Hence, in this study, we focused on the production of the chemokine “interferon-gamma-inducible protein 10 kDa,” or IP-10/CXCL10, by cultured SJL/J mouse astrocytes infected with the BeAn strain of TMEV and its capacity to attract activated T cells. The analysis of the whole murine genome by DNA hybridization with cRNAs from mock- and TMEV-infected cultures revealed the upregulation of six sequences that potentially encode for CXCL10. This increased CXCL10 expression was validated by PCR and qPCR. The presence of this chemokine was further demonstrated by enzyme-linked immunoassay (ELISA). Significantly, astrocytes from BALB/c mice, a strain resistant to demyelination, did not produce CXCL10. The secreted CXCL10 was biologically active, inducing chemoattraction of activated lymphocytes. The inflammatory cytokines, IL-1α, IFN-γ, and TNF-α, were strong inducers of CXCL10 in astrocytes. Serum from TMEV-infected SJL/J but not BALB/c mice contains CXCL10, the levels of which peak at the onset of the clinical disease. Finally, this in vitro inflammation model was fully inhibited by 17β-estradiol and four selective estrogen receptor modulators, as demonstrated by ELISA and qPCR.     

Terminal Deletion of 11q with Significant Late-Onset Combined Immune Deficiency

Purpose

We report a 45-year old female adult patient with terminal deletion of chromosome 11q resulting in clinical phenotype of late-onset combined immunodeficiency.

Methods

We describe the clinical phenotype and discuss the similarities between our patient and those with chromosome 22q11.2 deletion syndrome. Immunological evaluation included immunoglobulin levels, vaccine responses, number and function of T, NK and B cell subsets and comparative genomic hybridization test of blood and fibroblasts.

Results

The patient suffered from recurrent pneumococcal pneumonia and genital and cutaneous condylomas. She had a history of learning difficulties, dysmorphic features, autoimmune thyroiditis, chronic thrombocytopenia and severe asthma. We found Paris-Trousseau type thrombocytopenia, B-, T- and NK-lymphopenia, T cell oligoclonality and IgG hypogammaglobulinemia with inability to respond to pneumococcal polysaccharide, tetanus and diphtheria vaccines. A terminal deletion of chromosome 11q compatible with partial Jacobsen syndrome was found.

Conclusions

This confirms Jacobsen syndrome as a chromosome deletion syndrome able to cause combined immunodeficiency.     

Copolymers of bipyridinium and metal (Zn & Ni) porphyrin derivatives; theoretical insights and electrochemical activity towards CO2

This study reports the electropolymerization of novel keto functionalized octaethyl metal porphyrins (Zn²⁺ and Ni²⁺) in the presence of 4,4′-bipyridine (4,4′-bpy) as a bridging nucleophile. The polymer films were characterized by electrochemical, spectroscopic (UV-Vis, XPS, FT-IR and Raman spectroscopy) and imaging (AFM and SEM) techniques. The absorption and electronic spectra confirm the presence of both porphyrin and 4,4′-bipyridine units in the film. The surface morphology reveals homogeneous film deposition with average roughness values of approx. 8 nm. The theoretical studies performed offered insights into the interplay of different metal centres (Zn²⁺ and Ni²⁺) and the keto functionality of the porphyrin unit in the formation of copolymer films. The electrochemical interaction of polymer films with CO₂ suggests a reversible trap and release of CO₂ with low energy barriers for both the polymers.

Electropolymerization of keto functionalized porphyrins and 4,4′-bipyridine.