Physical properties and structural characteristics of particulate matter emitted from a diesel engine fueled with biodiesel blends.

This research explores the influence of renewable fuels, including three kinds of biodiesel along with ethanol on the physical properties and structural characteristics of particulate matter (PM) emitted from a diesel engine in comparison with pure diesel. After adding 10 vol% of grape seed biodiesel, coffee biodiesel and eucalyptus oil into diesel, three biodiesel blended fuels (10% grape seed biodiesel (DGs10), 10% spent coffee ground biodiesel (DC10) and eucalyptus oil biodiesel (DEu10)) were produced and tested in this study. Besides, one ethanol blend containing 9 vol% of ethanol and 1 vol% of biodiesel (blend stabilizer) was also tested to do the comparison. In the present study, scanning transmission electron microscope (STEM) and scanning electron microscope (SEM) were employed for analyzing the microstructure, nanostructure and electron diffraction pattern of PM. Raman spectrometer (RS) was also used for the analysis of structural characterization of PM. In addition, several experimental instruments like microbalance, measuring cup, viscometer, oxygen bomb calorimeter and Gas Chromatography-Mass Spectrometer (GC-MS) were employed to detect the fuel properties, including density, heating value, viscosity, composition and cetane number. A conclusion can be drawn that both biodiesel blends and ethanol blend have a changing effect on the PM properties compared to pure diesel, where biodiesel blends have a slightly weaker influence than ethanol blend. Regarding the biodiesel blends, DGs10 has more impact than DC10 and DEu10 in changes of PM properties, particularly in the reduction of PM mass, making it a good candidate for renewable fuel for diesel engines.

Physical, chemical, and cell toxicity properties of mature/aged particulate matter (PM) trapped in a diesel particulate filter (DPF) along with the results from freshly produced PM of a diesel engine.

The lifetime and efficiency of diesel particulate filters (DPFs) strongly depend on the proper and periodic cleaning and servicing. Unfortunately, in some cases, inappropriate methods are applied to clean the DPFs, e.g., using air compressors without proper disposal procedures which can have negative impacts on human health, the environment, and DPF's efficiency. However, there is no information available about the properties of this kind of PM. This research is therefore presented to explore the physicochemical and toxicity properties of aged PM trapped in a DPF (using compressed air for PM sampling) employing STEM, SEM, EDS, Organic Carbon Analyzer, TGA/DSC, and Raman Spectrometer for investigating the physicochemical properties, and assays of cell viability, cellular reactive oxygen species (ROS), interleukin-6, and tumor necrosis factor-alpha (TNF-α) for investigating the toxicity properties. Also, analyses from fresh PM samples from the diesel vehicle at two engine speeds are presented. It is found that at a certain/fixed PM number/mass for all three samples tested, the PM from DPF compared with the fresh PM can have both positive (particularly having the lowest water-soluble total carbon ratio) and negative impacts on human health (particularly having the highest cell death rate of 13.4%, ROS, and TNF-α) and the environment.

Physicochemical and cell toxicity properties of particulate matter (PM) from a diesel vehicle fueled with diesel, spent coffee ground biodiesel, and ethanol.

The literature shows that information about the physical, chemical, and cell toxicity properties of particulate matter (PM) from diesel vehicles is not rich as the existence of a remarkable number of studies about the combustion, performance, and emissions of diesel vehicles using renewable liquid fuels, particularly biodiesels and alcohols. Also, the PM analyses from combustion of spent coffee ground biodiesel have not been comprehensively explored. Therefore, this research is presented. Pure diesel, 90% diesel + 10% biodiesel, and 90% diesel + 9% ethanol + 1% biodiesel, volume bases, were tested under a fast idle condition. STEM, SEM, EDS, Organic Carbon Analyzer, TGA/DSC, and Raman Spectrometer were employed for investigating the PM physical and chemical properties, and assays of cell viability, cellular reactive oxygen species, interleukin-6, and tumor necrosis factor-alpha were examined for investigating the PM cell toxicity properties. It is found that the application of both biodiesel and ethanol has the potential to change the PM properties, while the impact of ethanol is more than biodiesel on the changes. Regarding the important aspects, biodiesel can be effective for better human health (due to a decrease in cell death (-60.8%)) as well as good diesel particulate filter efficiency (due to lower activation energy (-7.6%) and frequency factor (-83.2%)). However, despite a higher impact of ethanol on the reductions in activation energy (-24.8%) and frequency factor (-99.0%), this fuel causes an increase in cell death (84.1%). Therefore, biodiesel can be an appropriate fuel to have a positive impact on human health, the environment, and emissions catalysts performance, simultaneously.

Observation and Suppression of Stacking Interface States in Sandwich-Structured Quantum Dot Light-Emitting Diodes.

Interfacial quality of functional layers plays an important role in the carrier transport of sandwich-structured devices. Although the suppression of interface states is crucial to the overall device performance, our understanding on their formation and annihilation mechanism via direct characterization is still quite limited. Here, we present a thorough study on the interface states present in the electron transport layer (ETL) of blue quantum dot (QD) light-emitting diodes (QLEDs). A ZnO/ZnMgO bilayer ETL is adopted to enhance the electron injection into blue QDs. By probing the ETL band structure with photoelectron spectroscopy, we discover that substantial band bending exists at the ZnO/ZnMgO interface, elucidating the presence of a high density of interface states which hinder electron transport. By inserting a ZnO@ZMO interlayer composed of mixed ZnO and ZnMgO nanoparticles, the band bending and thus the interface states are observed to reduce significantly. We attribute this to the hybrid surface properties of ZnO@ZMO, which can annihilate the surface states of both the ZnO and ZnMgO layers. The introduction of a bridging layer has led to ∼40% enhancement in the power efficiency of blue QLEDs and noticeable performance boosts in green and red QLEDs. The findings here demonstrate a direct observation of interface states via detailed band structure studies and outline a potential pathway for eliminating these states for better performances in sandwich-structured devices.

Efficiency Improvement of Quantum Dot Light-Emitting Diodes via Thermal Damage Suppression with HATCN.

With many advantages including superior color saturation and efficiency, quantum dot light-emitting diodes (QLEDs) are considered a promising candidate for the next-generation displays. Emission uniformity over the entire device area is a critical factor to the overall performance and reliability of QLEDs. In this work, we performed a thorough study on the origin of dark spots commonly observed in operating QLEDs and developed a strategy to eliminate these defects. Using advanced cross section fabrication and imaging techniques, we discovered the occurrence of voids in the organic hole transport layer and directly correlated them to the observed emission nonuniformity. Further investigations revealed that these voids are thermal damages induced during the subsequent thermal deposition of other functional layers and can act as leakage paths in the device. By inserting a thermo-tolerant 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HATCN) interlayer with an optimized thickness, the thermally induced dark spots can be completely suppressed, leading to a current efficiency increase by 18%. We further demonstrated that such a thermal passivation strategy can work universally for various types of organic layers with low thermal stability. Our findings here provide important guidance in enhancing the performances and reliability of QLEDs and also other sandwich-structured devices via the passivation of heat-sensitive layers.

Case Report: Malignant Transformation of Noma: Repair by Forearm Flap.

Noma is a progressive infectious disease manifested by a necrotic ulcer of the mouth and face. It usually occurs in poor, malnourished children, with about 30,000-140,000 cases each year and a low survival rate. The exact cause of noma remains unclear, but bacterial infection has been postulated to be a major cause of this disease. Antibiotics and improved nutrition could help inhibit the progression of noma, but most patients still require oral surgery because of the bacterial infection-induced tissue damage. In this study, we report an unusual case of a noma patient whose facial lesion developed a malignancy. The necrotic tissue and infectious area were surgically resected, and a forearm flap was used to repair the patient's facial defect. This case aimed at increasing people's awareness of tropical diseases such as noma.

Homogeneous Core/Shell NiMoO4@NiMoO4 and Activated Carbon for High Performance Asymmetric Supercapacitor.

Here, we report the extraordinary electrochemical energy storage capability of NiMoO4@NiMoO4 homogeneous hierarchical nanosheet-on-nanowire arrays (SOWAs), synthesized on nickel substrate by a two-stage hydrothermal process. Comparatively speaking, the SOWAs electrode displays superior electrochemical performances over the pure NiMoO4 nanowire arrays. Such improvements can be ascribed to the characteristic homogeneous hierarchical structure, which not only effectively increases the active surface areas for fast charge transfer, but also reduces the electrode resistance significantly by eliminating the potential barrier at the nanowire/nanosheet junction, an issue usually seen in other reported heterogeneous architectures. We further evaluate the performances of the SOWAs by constructing an asymmetric hybrid supercapacitor (ASC) with the SOWAs and activated carbon (AC). The optimized ASC shows excellent electrochemical performances with 47.2 Wh/kg in energy density of 1.38 kW/kg at 0-1.2 V. Moreover, the specific capacity retention can be as high as 91.4% after 4000 cycles, illustrating the remarkable cycling stability of the NiMoO4@NiMoO4//AC ASC device. Our results show that this unique NiMoO4@NiMoO4 SOWA has great prospects for future energy storage applications.

Tailoring the Photoluminescence Excitation Dependence of the Carbon Dots via an Alkali Treatment.

Carbon dots (CDs) have shown great potential in various applications including biomedicines and optoelectronics. However, the origin of their photoluminescence excitation dependence (PL-ED) still remains uncertain, and this can limit the full exploit of their wonderful optical properties. Here we studied the mechanism for the PL-ED of solvothermally synthesized CDs using an alkali treatment. As-synthesized CDs were found to agglomerate and exhibited multicolor emissions with strong PL-ED. The alkali treatment can effectively break down the clusters into individual CDs via the hydrolysis of the amide and ester bonds that link the CDs together. This process effectively narrowed the emission line width and suppressed the observed PL-ED. The understanding of the excitation dependence mechanism here outlined a novel strategy for tailoring of the PL-ED of CDs via a synergy of chemical and physical processes, thus enhancing the versatility of CDs for a broader spectrum of applications.

Glucose-regulated protein 78 and heparanase expression in oral squamous cell carcinoma: correlations and prognostic significance.

BACKGROUND: The aim of the present study was to investigate the expression of glucose-related protein 78 (GRP78) and heparanase (HPA) in oral squamous cell carcinoma (OSCC) and their relationship with clinicopathological parameters and potential implications for survival. METHODS: A total of 46 patients with OSCC and 10 normal individuals were recruited for the study. GRP78 and HPA expression were determined in the lesion tissues using immunohistochemical analysis. The correlation between GRP78 and HPA was assessed using the Spearman correlation analysis. The associations of GRP78 and HPA with clinicopathological characteristics and survival were examined using the x2-test, Kaplan-Meier, or Cox regression. RESULTS: Patients with OSCC showed a statistically significant higher prevalence of GRP78 and HPA expression than normal oral tissues. GRP78 and HPA expression was positively correlated with size, TNM stage, histological grade, lymphatic metastasis, and distant metastasis in OSCC patients. GRP78 expression was also positively correlated with HPA expression. Positive GRP78 and HPA expression was inversely correlated with survival in OSCC patients. CONCLUSIONS: HPA expression was found to be positively correlated with GRP78 expression. GRP78 and HPA are biomarkers that may have the potential to guide the treatment of oral cancer patients.

Down-regulation of RIP1 by 2-deoxy-D-glucose sensitizes breast cancer cells to TRAIL-induced apoptosis.

TNF-related apoptosis-inducing ligand (TRAIL) appears to be a promising anticancer agent as it specifically kills a wide variety of cancer cells. However, resistance of subpopulations of cancer cells to TRAIL-induced cell death remains a major obstacle for successful treatment of cancer using TRAIL-based therapy. In this report we show that the hexokinase inhibitor 2-deoxy-d-glucose (2-DG) efficiently enhances TRAIL-induced apoptosis through downregulation of receptor-interacting protein kinase 1 (RIP1) in breast cancer cells. Although 2-DG alone did not kill breast cancer cells, it sensitized the cells to TRAIL-induced cell death. This could be efficiently inhibited by blockage of the caspase cascade, suggesting 2-DG augments TRAIL-mediated apoptotic signaling. Indeed, treatment with 2-DG resulted in upregulation of TRAIL receptor 2 (TRAIL-R2), downregulation of cIAP1 and XIAP, and reduction in RIP1. The latter appeared to play an important role in regulating sensitivity of breast cancer cells to TRAIL, in that knockdown of RIP1 recapitulated, at least in part, the effect of 2-DG on TRAIL-induced apoptosis. Taken together, these results indicate that 2-DG enhances TRAIL-induced apoptosis in breast cancer cells by multiple mechanisms including suppression of RIP1, and highlight the potential therapeutic benefit of combinations of 2-DG and TRAIL in the treatment of breast cancer.

[Expression of vascular endothelial growth factor, vascular endothelial growth factor receptor-3 and nm23-H1 in oral squamous cell carcinoma].

OBJECTIVE: To explore the role of vascular endothelial growth factor C (VEGF-C), VEGFR-3 and nm23-H(1) in lymphatic metastasis of oral squamous cell carcinoma (OSCC). METHODS: The expression of VEGF-C, VEGFR-3 and nm23-H(1) were examined by immunohistochemical SP method. The lymphatic vessels density (LVD) in tumors was counted and analyzed with clinicopathologic parameters. RESULTS: VEGF-C, LVD and nm23-H(1) expressions were significantly different between OSCC and benign and precancerous lesions (P < 0.05). VEGF-C was correlated with lymph node metastasis and LVD (P < 0.01). nm23-H(1) was related to clinical stage, histological grade and lymphatic metastasis (P < 0.05). CONCLUSIONS: The high expressions of VEGF-C/VEGFR-3 and inactivation of nm23-H(1) may play an important role in lymphatic metastasis in OSCC.

[Levels of plasma interleukin-18 and interferon-gamma in patients with coronary heart disease].

OBJECTIVE: To investigate the role of interleukin-18 (IL-18) and interferon-gamma (IFN-gamma) in coronary heart disease (CHD). METHODS: The levels of plasma IL-18 and IFN-gamma in 45 patients with CHD and 30 normal volunteers were determined by enzyme linked immunoadsorbent assay (ELISA). The correlation between the levels of these two cytokines and the relationship between their levels and the state of CHD were analyzed. RESULTS: The plasma levels of IL-18 and IFN-gamma in patients with CHD were increased significantly when compared to those in normal controls [IL-18: (373.6+/-176.7) ng/L vs. (226.3+/-88.9) ng/L, P<0.01; IFN-gamma: (1.769+/-0.087) ng/L vs. (0.087+/-0.038) ng/L, P<0.01]. The two cytokines were positively correlated significantly (r=0.788, P<0.01)]. The plasma levels of IL-18 and IFN-gamma were significantly different in different states of CHD, and they increased with the aggravation of CHD respectively (all P<0.01). Moreover, the plasma levels of IL-18 and IFN-gamma in patients complicated with heart failure (HF) were higher than those not complicated with HF, respectively (all P<0.01). CONCLUSION: The findings suggest that IL-18 and IFN-gamma may participate in the pathogenesis and progression of CHD. The plasma levels of two cytokines may be used as parameters of estimation the morbid state of CHD.