Highly efficient green-emitting ZnO:Cu2+ phosphors for NUV-pumped white-emitting diodes.

Phosphor-converted white light-emitting diodes (WLEDs) have received significant attention; however, the leaked light from their blue InGaN chips has an undesirable effect on human health. Hence, it is necessary to develop red, green, and blue-emitting phosphors, which can be excited by an NUV chip instead of a blue chip. Herein, green-emitting ZnO:Cu2+ phosphors have been successfully synthesized by a simple and facile thermal diffusion method. The obtained powder shows a broad emission band peaking at 525 nm and a strong absorption peak at 377 nm. The ZnO:5%Cu2+ phosphor annealed at 800 °C in 2 hours revealed a lifetime of 0.57 ms, an activation energy of 0.212 eV, and the highest emission intensity with (x, y) CIE colour coordinates (0.3130, 0.5253). A WLED prototype has been fabricated by coating the ZnO:5%Cu2+ phosphor on an NUV 375 nm LED chip, where this coated phosphor shows a high quantum efficiency (QE) of 56.6%. This is, so far, the highest reported QE value for ZnO-based phosphors. These results suggest that the ZnO:Cu2+ phosphor could be an excellent candidate for NUV-pumped phosphor-converted WLED applications.

High quantum efficiency and excellent color purity of red-emitting Eu3+-heavily doped Gd(BO2)3-Y3BO6-GdBO3 phosphors for NUV-pumped WLED applications.

Eu3+-doped phosphors have been much attractive owing to their narrow-band red emission peak at 610-630 nm with high color purity; however, the weak and narrow absorption band in the NUV region limits their applications. Doping a higher amount of Eu3+ ions into a non-concentration quenching host could be key to enhancing the efficiency of the absorption value and emission intensity. Hence, the design of Eu3+-heavily doped phosphors with a suitable host lattice is key for applications. In this study, red-emitting Eu3+-doped Gd(BO2)3-Y3BO6-GdBO3 (GdYGd:Eu3+) phosphor with a high quantum efficiency of 58.4% and excellent color purity of 99.5% is reported for the first time. The phosphor is efficiently excited by NUV light at 394 nm and emits a strong red emission band in the 590-710 nm range, peaking at 612 nm. The optimal annealing temperature and Eu3+ doping content to obtain the strongest PL intensity are 1100 °C and 20 mol%, respectively. The optimized GdYGd:Eu3+ phosphor possesses a high activation energy of 0.319 eV and a lifetime of 1.14 ms. An illustration of phosphor-coated NUV LED with chromaticity coordinates (x = 0.5636,y = 0.2961) was successfully synthesized, demonstrating the great potential of GdYGd:Eu3+ phosphor for NUV-pumped WLED applications.

Binder ratio in the two-dimensional q-state clock model.

We study phase transition properties of the two-dimensional q-state clock model by an extensive Monte Carlo simulation. By analyzing the Binder ratio and its temperature derivative, we confirm that the two-dimensional q-state clock model exhibits two distinct Kosterlitz-Thouless phase transitions for q=5,6 but it has one second-order phase transition for q=4. The critical temperatures are estimated quite accurately from the crossing behavior of the Binder ratio (for q<5) and from negative divergent dips of the derivative of the Binder ratio (for q≥5) around these critical points. We also calculate the correlation length, the helicity modulus, and the derivative of the helicity modulus, and analyze their behaviors in different phases in detail.

Low serum prealbumin concentration predicts long-term mortality in maintenance hemodialysis patients with hepatitis B and/or C virus infections.

BACKGROUND AND AIM: A low serum prealbumin concentration is common in maintenance hemodialysis patients with hepatitis B and C and may be associated with mortality. In this study, we assessed Department of Nephrology and Hemodialysis predictive value of a low serum prealbumin concentration on mortality in HD patients using reused low-flux dialyzers who were infected with hepatitis B and/or C virus. METHODS: We used serum prealbumin levels to predict the long-term mortality of 326 hemodialysis patients. The patients were divided into two groups: group 1 (n = 140, with hepatitis B and/or C virus infections), and group 2 (n = 186, without hepatitis virus infections). RESULTS: During a 5-year follow-up, there were 75 deaths due to all-cause mortality (23.0%). Mortality was significantly higher (P < 0.001) in patients with hepatitis B and/or C infection (44%) than in those without hepatitis infection (8%). Serum prealbumin was lower in the hepatitis infected group and mortality group than in non-infected group and survival group. Multivariate Cox regression analysis showed that long duration of HD and lower serum prealbumin and albumin were related to mortality in patients undergoing maintenance HD. Receiver operating characteristic curves showed that serum prealbumin had a good prognostic value in predicting mortality in both groups with hepatitis B and/or C virus infection and without hepatitis infection (AUC = 0.792 [95% confidence interval: 0.714-0.87], P < 0.001; cut-off value = 24.5 mg/dl, sensitivity = 62.3%, and specificity = 88.6%). CONCLUSION: In HD patients, serum prealbumin was a good prognostic biomarker of mortality in both groups of patients with hepatitis B and/or C virus infections and without hepatitis infections.

Improvement in gross motor function and muscle tone in children with cerebral palsy related to neonatal icterus: an open-label, uncontrolled clinical trial.

BACKGROUND: Although stem cell transplantation has been successfully performed for cerebral palsy (CP) related to oxygen deprivation, clinical trials involving the use of stem cell transplantation for CP related to neonatal icterus have not been reported. The aim of this study was to evaluate the effectiveness of transplantation of autologous bone marrow mononuclear cell (BMMC) for improving gross motor function and muscle tone in children with CP related to neonatal icterus. METHODS: This open-label, uncontrolled clinical trial, which included 25 patients with CP related to neonatal icterus who had a Gross Motor Function Classification System (GMFCS) score between level II and level V, was conducted between July 2014 and July 2017 at Vinmec International Hospital (Vietnam). BMMC were harvested from the patients' iliac crests. Two procedures involving BMMC transplantation via the intrathecal route were performed: the first transplantation was performed at baseline, and the second transplantation was performed 6 months after the first transplantation. Gross motor function and muscle tone were measured at three time points (baseline, 6 months, and 12 months) using the Gross Motor Function Measure (GMFM) and the Modified Ashworth Scale. RESULTS: In this trial, we observed significant improvement in gross motor function and a significant decrease in muscle tone values. Total score on the 88-item GMFM (GMFM-88), scores on each GMFM-88 domain, and the 66-item GMFM (GMFM-66) percentile were significantly enhanced at 6 months and 12 months after the first transplantation compared with the corresponding baseline measurements (p-values < 0.05). In addition, a significant reduction was observed in muscle tone score after the transplantations (p-value < 0.05). CONCLUSION: Autologous BMMC transplantation can improve gross motor function and muscle tone in children with CP related to neonatal icterus. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03123562 . Retrospectively registered on December 26, 2017.

Evaluation of Antioxidant, Anti-cholinesterase, and Anti-inflammatory Effects of Culinary Mushroom Pleurotus pulmonarius

Culinary mushroom Pleurotus pulmonarius has been popular in Asian countries. In this study, the anti-oxidant, cholinesterase, and inflammation inhibitory activities of methanol extract (ME) of fruiting bodies of P. pulmonarius were evaluted. The 1,1-diphenyl-2-picryl-hydrazy free radical scavenging activity of ME at 2.0 mg/mL was comparable to that of butylated hydroxytoluene, the standard reference. The ME exhibited significantly higher hydroxyl radical scavenging activity than butylated hydroxytoluene. ME showed slightly lower but moderate inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase than galantamine, a standard AChE inhibitor. It also exhibited protective effect against cytotoxicity to PC-12 cells induced by glutamate (10~100 µg/mL), inhibitory effect on nitric oxide (NO) production and inducible nitric oxide synthase protein expression in lipopolysaccharide-stimulated RAW 264.7 macrophages, and carrageenan-induced paw edema in a rat model. High-performance liquid chromatography analysis revealed the ME of P. pulmonarius contained at least 10 phenolic compounds and some of them were identified by the comparison with known standard phenolics. Taken together, our results demonstrate that fruiting bodies of P. pulmonarius possess antioxidant, anti-cholinesterase, and inflammation inhibitory activities.

Ethanol Production from Various Sugars and Cellulosic Biomass by White Rot Fungus Lenzites betulinus

Lenzites betulinus, known as gilled polypore belongs to Basidiomycota was isolated from fruiting body on broadleaf dead trees. It was found that the mycelia of white rot fungus Lenzites betulinus IUM 5468 produced ethanol from various sugars, including glucose, mannose, galactose, and cellobiose with a yield of 0.38, 0.26, 0.07, and 0.26 g of ethanol per gram of sugar consumed, respectively. This fungus relatively exhibited a good ethanol production from xylose at 0.26 g of ethanol per gram of sugar consumed. However, the ethanol conversion rate of arabinose was relatively low (at 0.07 g of ethanol per gram sugar). L. betulinus was capable of producing ethanol directly from rice straw and corn stalks at 0.22 g and 0.16 g of ethanol per gram of substrates, respectively, when this fungus was cultured in a basal medium containing 20 g/L rice straw or corn stalks. These results indicate that L. betulinus can produce ethanol efficiently from glucose, mannose, and cellobiose and produce ethanol very poorly from galactose and arabinose. Therefore, it is suggested that this fungus can ferment ethanol from various sugars and hydrolyze cellulosic materials to sugars and convert them to ethanol simultaneously.