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P-type dehydrated nanotube titanic acid (DNTA) can significantly enhance hole injection and transport in holes-only transport devices. Through fabricated and characterized organic light-emitting diodes (OLEDs) and by using a DNTA-poly(vinylcarbazole) (PVK) nanocomposite as the hole transport layer, it was found that the performance of these devices was greatly improved with a higher luminance, and enhanced efficiency, and a lower turn-on voltage.

The electroluminescent properties of three different device structures (A:ITO/SiO[sub 2]/Alq[sub 3]/SiO[sub 2]/Al, B:ITO/Alq[sub 3]/SiO[sub 2]/Al, and C:ITO/SiO[sub 2]/Alq[sub 3]/Al) based on the tris-(8-hydroxyquinoline) aluminum (Alq[sub 3]) were investigated. A blue electroluminescence at 457 nm was obtained from device (A) and (B), and the green emission at 518 nm was obtained from device (C). It is generally agreed that the green emission originates from the recombination of the singlet excitons. The blue emission, here, is attributed to the direct transitions between the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital of Alq[sub 3]. This is due to the electric field-induced excitons dissociation and the space charge accumulation at the interface. The high internal electric field enhances the dissociation of neutral singlet excitations into LUMO states and inhibits the formation of the singlet excitons, therefore enhances the probability for direct interband transitions of the relaxed carriers. The intensity of the blue emission is dependent on the operating frequency. This indicates that space charge accumulation time and effective internal electric field are responsible for the blue emission intensity. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Lung cancer is one of the lethal cancers and one of the major causes of cancer-related mortalities across the globe. SIRT1 gene has been reported to be involved in the progression and tumorigenesis of several types of cancers. However, the role of SIRT1 gene is in the progression of lung cancer is poorly understood. Against this backdrop, the present study was designed to investigate the expression of SIRT1 gene in different lung cancer cell lines. Moreover, the relation between the expression of this gene and the sensitivity of lung cancer cell lines to the anticancer effects of cisplatin was also investigated. MATERIALS AND METHODS: Expression of SIRT1 gene was determined by quantitative RTPCR. Protein expression was examined by Western blotting. Anti-proliferative activity was determined by MTT and colony formation assay. Apoptotic populations were determined by annexin V/IP staining and flow cytometry. RESULTS: The results revealed that NCI-H125 showed lowest, NCI-H226 showed moderate, while as NCI-H358 exhibited the highest expression of SIRT1. The three differentially SIRT1 expressing cancer cell lines were subjected to cisplatin treatment. It was observed that cisplatin exhibited the highest anticancer activity against NCI-H125 (IC50, 1.25 μM) and lowest against NCI-H358 (IC50, 4.5 μM). Moreover, cisplatin leads to highest inhibition of colony formation and apoptosis in NCI-H125 and lowest against NCI-H358. CONCLUSIONS: Expression of SIRT1 gene determines the sensitivity of lung cancer cells to anticancer effects of cisplatin. This work will pave for understanding the role of SIRT1 gene in cancer progression. [ABSTRACT FROM AUTHOR]

OBJECTIVE: MicroRNAs have emerged as key regulators in cancer cell biology. In the present study, we investigate the role and the involving mechanism of miR-370 in the progression of liver cancers. MATERIALS AND METHODS: MiR-370 levels were detected by real-time PCR assay. Cell proliferation of HepG2, MHCC-97H and SMMC-7721 was determined by MTT assay. PI staining was detected by FACS analysis. Colony formation was used to test liver cancer cell growth. FoxO3a and Akt expression was determined by western blotting analysis. RESULTS: MiR-370 level was significantly down-regulated in liver cancer cells. Functional analysis revealed that miR-370 mimics suppressed cell proliferation of liver cancer cells, while transfection with miR-370 inhibitor increased cell proliferation of liver cancer cells. Moreover, miR-370 mimics induced cell death of HepG2. Furthermore, Western blotting analysis results demonstrated that miR-370 inhibited the proliferation of liver cancer cells by activating FoxO3a. CONCLUSIONS: MiR-370 inhibited cell proliferation of liver cancer cells by PI3K/Akt signaling pathway. It worked as a tumor suppressor to suppress the progression of human liver cancers. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the feasibility of using a reduced radiation dose and reduced iodine intake (i.e., "double low": low tube voltage/low iodine dose contrast agent) scanning protocol and the adaptive iterative dose reduction (AIDR) reconstruction algorithm in coronary heart disease (CHD) patients with a BMI of 26-30 kg/m(2). Materials and Methods: One-hundred and seventy-nine consecutive CHD patients with a body mass index >26 kg/m² but <30 kg/m² were randomly assigned to two groups (group A: 53 men, 39 women, average age 61.83 ± 11.84 years, and group B: 40 men, 47 women, average age 62.25 ± 11.37 years) based on tube voltage, contrast agent, and algorithm used. Group A underwent the "double low" protocol (iodixanol at 270 mg iodine/ml, 100 kVp tube voltage, and AIDR). Group B received the conventional protocol [iopamidol at 370 mg iodine/ml, 120 kVp tube voltage, and filtered back projection (FBP)]. Results: The volume CT dose index (CTDIvol), dose-length product (DLP), effective dose (ED), and iodine intake of patients in "double low" group A were significantly lower than the "conventional" group B (p < 0.001). The mean intraluminal attenuation and contrast enhancement in group A were also significantly less than group B (p < 0.001), whereas the image noise using AIDR in group A was significantly lower than group B using FBP (p < 0.001). However, the signal-to- noise ratio (SNR), contrast-to-noise ratio (CNR), and image-quality scores between the two groups were comparable. Conclusions: Use of 320-row CT with a "double low" scanning protocol for CCTA in patients with a BMI of 26-30 kg/m(2) not only provided images of diagnostic quality but also reduced both radiation dose and iodine intake during scanning. [ABSTRACT FROM AUTHOR]

To meet the rapid operation need for leakage protection of the coal mine distribution network, a novel method of leakage line discrimination is proposed based on signals mutual distance degree model and the transient course feature. It is concluded that the instantaneous zero-sequence current waveform postures of leakage line is different from the normal lines in transient course, while the normal lines are similar. Signals mutual distance degree model is built. Using this model to recognise zero-sequence currents waveform posture, the criterion of leakage line selection is formed. Simulation and experiment results indicate that this method achieves instantaneous selection operation in both transverse and longitudinal direction, and is simple and rapid. [ABSTRACT FROM AUTHOR]

The effect of KClO3+3Mg additive concentration on the combustion ability of Si+C 'weekly exothermic' mixture has been studied. The critical concentration of KClO3+3Mg mixture for combustion to occur has been found to be 0·02 mol. The morphological and structural characteristics of products have been investigated as a function of the additive concentration, reaction pressure and the initial sample diameter. The reaction products have been analysed by X-ray diffraction, scanning electron microscopy and BET surface area analysis methods. It has been shown that β-SiC hollow globules composed of submicrometre size particles have been formed during the combustion reaction. After leaching and grinding of final products ultrafine and single phase β-SiC powders with particles size less than 0·5 μm, and specific surface area of 18·5 m2 g–1 have been synthesised. [ABSTRACT FROM AUTHOR]

Electroluminescence (EL) of bilayer organic light-emitting diodes based on N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD) and 2-(4'-biphenyl)-5-(4”- tert-butylphenyl)-1,3,4-oxadiazole (PBD) were reported. The EL spectra of bilayer device ITO/TPD/PBD/Al consist of monomolecular emission from TPD, exciplex emission and charge carriers cross recombination at the TPD/PBD interface. By varying the thickness of each organic layer while keeping the thickness of the whole device constant, three kinds of bilayer devices were fabricated and their EL and photoluminescence spectra were compared with each other, and our experimental data show that charge tunneling and cross recombination coexist at the TPD/PBD interface, and these two processes compete with each other under high electric fields. [ABSTRACT FROM AUTHOR]

We did the resistivity and scanning tunneling microscope/spectroscopy (STM/STS) experiments at different temperatures and magnetic fields to investigate the origin of the turn-on (t-o) phenomenon of Td - MoTe2. There are two interesting observations. Firstly, magnetoresistance (MR) follows the Kohler's rule scaling: MR ~ (H/ρ0)m with m ≈ 1.92 and the t-o temperature T* under different magnetic fields can also be scaled by T* ~ (H - Hc)υ with υ = 1/2. Secondly, a combination of compensated electron-hole pockets and a possible electronic structure phase transition induced by the temperature have been validated in Td - MoTe2 by the STM/STS experiments. Compared with the STS of Td - MoTe2 single crystal under H = 0, the STS hardly changes even when the applied field is up to 7 T. The origins of the t-o phenomenon in Td - MoTe2 are discussed. Meanwhile, we analyzed the universality and applicability of the t-o phenomenon in the extreme MR materials with almost balanced hole and electron densities as well as with other systems where the density of hole or electron is in a dominant position. [ABSTRACT FROM AUTHOR]

Objective: Brain and muscle ARNT-like protein 1 (BMAL1) is a core component of hepatocyte molecular clock and plays an important role in the regulation of other related rhythmic genes in the body through a transcriptional-translational feedback loop in molecular circadian oscillations. Therefore, the aim of this study was to investigate the role of BMAL1 in the rat periodontitis-induced liver injury. Methods: Twelve male Wistar rats were divided into the control group and the periodontitis group according to the random number table method. The rats in the control group were untreated. The periodontitis models were established by ligating the necks of the bilateral maxillary first molars in the periodontitis group rats. After 8 weeks, periodontal clinical indexes of rats in both groups were examined and executed. Micro-CT scans of the maxilla were performed and levels of the alveolar bone resorption were analyzed. Pathological changes in periodontal and liver tissue of rats in two groups were detected by HE and oil red O staining. Biochemical kits were used to detect glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), total cholesterol (TC) and triglycerides (TG) in serum. The gene and protein expression levels of BMAL1, nuclear factor kappa-B (NF-κB) and tumor necrosis factor-α (TNF-α) in liver tissue were measured by real time fluorescent quantitative-PCR (qRT-PCR), immunohistochemistry (IHC) and Western blotting (WB) assays. Apoptosis was detected in liver tissues by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) kit staining. Results: The results of HE staining of maxillary first molars and micro-CT results of maxillary bones showed that alveolar bone resorption was significant in the periodontitis group of rats. The liver histopathology results showed infiltrated inflammatory cells in the liver tissue, disorganized liver cords and a large number of lipid droplets formed in the hepatocytes of the periodontitis group compared with the control group. The results of serum biochemical assay showed that the levels of GOT [(62.77±2.59) U/L], GPT [(47.54±1.04) U/L], TC [(3.19±0.23) mmol/L] and TG [(1.11±0.09) mmol/L] in the serum of rats with periodontitis were significantly higher than that in the control group respectively [GOT: (38.66±2.47) U/L, GPT: (31.48±1.57) U/L, TC: (1.60±0.05) mmol/L and TG: (0.61±0.09) mmol/L]( P= 0.003, P= 0.001, P= 0.002, P= 0.038). qRT-PCR results showed that the mRNA expression level of BMAL1 was significantly decreased in liver tissue of the periodontitis group [(0.60±0.04)%] compared to the control group [(1.01±0.07)%] ( t= 4.80, P= 0.009), while the mRNA expression levels of NF-κB and TNF-α [(1.62±0.12)%, (2.69±0.16)%] were significantly increased compared to the control group [(1.00±0.03)%, (1.03±0.16)%] ( P= 0.008, P= 0.002); IHC results showed that the protein expression level of BMAL1 in liver tissue of the periodontitis group (averaged optical density, AOD) (11.58±2.15) was down-regulated compared to the control group (AOD) (22.66±1.67) ( P= 0.015), while NF-κB and TNF-α (AOD) (31.77±2.69, 24.31±2.32) were up-regulated compared to the control group (AOD) (19.40±1.82, 11.92±0.94) ( P= 0.019, P= 0.008). WB results showed that the protein expression level of BMAL1 in liver tissue was down-regulated in the periodontitis group [(0.63±0.10)%] compared to the control group [(1.00±0.06)%] ( t= 3.19, P= 0.033), while NF-κB and TNF-α [(1.61±0.12)%, (2.82±0.23)%] were up-regulated compared to the control group [(1.00±0.12)%, (1.00±0.11)%] ( P= 0.022, P= 0.002). TUNEL staining showed increased apoptotic cells in the liver tissue of the periodontitis group of rats compared to the control group. Conclusions: Periodontitis may induce liver injury by down-regulating the BMAL1 expression levels in liver tissue, which in turn activates NF-κB signaling molecules, leading to the elevated levels of inflammation and apoptosis in rat liver.