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131.
132.
Non-small cell lung cancer (NSCLC), an aggressive subtype of pulmonary carcinomas with high mortality, accounts for 85% of all lung cancers. Drug resistance and high recurrence rates impede the chemotherapeutic effect, making it urgent to develop new anti-NSCLC agents. Recently, we have demonstrated that para-toluenesulfonamide is a potential anti-tumor agent in human castration-resistant prostate cancer (CRPC) through inhibition of Akt/mTOR/p70S6 kinase pathway and lipid raft disruption. In the current study, we further addressed the critical role of cholesterol-enriched membrane microdomain and autophagic activation to para-toluenesulfonamide action in killing NSCLC. Similar in CRPC, para-toluenesulfonamide inhibited the Akt/mTOR/p70S6K pathway in NSCLC cell lines NCI-H460 and A549, leading to G1 arrest of the cell cycle and apoptosis. Para-toluenesulfonamide significantly decreased the cholesterol levels of plasma membrane. External cholesterol supplement rescued para-toluenesulfonamide-mediated effects. Para-toluenesulfonamide induced a profound increase of LC3-II protein expression and a significant decrease of p62 expression. Double staining of lysosomes and cellular cholesterol showed para-toluenesulfonamide-induced lysosomal transportation of cholesterol, which was validated using flow cytometric analysis of lysosome staining. Moreover, autophagy inhibitors could blunt para-toluenesulfonamide-induced effect, indicating autophagy induction. In conclusion, the data suggest that para-toluenesulfonamide is an effective anticancer agent against NSCLC through G1 checkpoint arrest and apoptotic cell death. The disturbance of membrane cholesterol levels and autophagic activation may play a crucial role to para-toluenesulfonamide action.  相似文献   
133.
Characteristics of microscale hydrogen diffusion flames produced from sub-millimeter diameter (d = 0.2 and 0.48 mm) tubes are investigated using non-intrusive UV Raman scattering coupled with LIPF technique. Simultaneous, temporally and spatially resolved point measurements of temperature, major species concentrations (O2, N2, H2O, and H2), and absolute hydroxyl radical concentration (OH) are made in the microflames for the first time. The probe volume is 0.02 × 0.04 × 0.04 mm3. In addition, photographs and 2-D OH imaging techniques are employed to illustrate the flame shapes and reaction zones. Several important features are identified from the detailed measurements of microflames. Qualitative 2-D OH imaging indicates that a spherical flame is formed with a radius of about 1 mm as the tube diameter is reduced to 0.2 mm. Raman/LIPF measurements show that the coupled effect of ambient air leakage and pre-heating enhanced thermal diffusion of H2 leads to lean-burn conditions for the flame. The calculated characteristic features and properties indicate that the buoyancy effect is minor while the flames are in the convection–diffusion controlled regime because of low Peclet number. Also, the effect of Peclet number on the flame shape is minor as the flame is in the convection–diffusion controlled regime. Comparisons between the predicted and measured data indicate that the trends of temperature, major species, and OH distributions are properly modeled. However, the code does not properly predict the air entrainment and pre-heating enhanced thermal-diffusive effects. Therefore, thermal diffusion for light species and different combustion models might need to be considered in the simulation of microflame structure.  相似文献   
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135.
Three new pyranocoumarin derivatives, tamanolide (1), tamanolide D (2) and tamanolide P (3), were isolated from the almond seeds of Calophyllum inophyllum L. (Clusiaceae) grown in French Polynesia. These compounds, having an unprecedented C‐4 isobutyl substituent, have been characterized as a new class of pyranocoumarins called tamanolides. Their structures were elucidated on the basis of 1D and 2D NMR techniques (COSY, NOESY, HSQC and HMBC) in association with MS (HR‐ESI‐MS) data analysis. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
136.
Micro capillary pumped loop system for a cooling high power device   总被引:1,自引:0,他引:1  
This work discusses the operation of a capillary-driven two-phase loop, configured on a micro capillary pumped loop (MCPL) system without an external power supply but capable of automatic heat transmission. The MCPL device, fabricated using MEMS (microelectricomechanical system) technology, was tested and yielded the following results: first, the proposed design of a new MCPL system with a water reservoir operating at low pressures is feasible and requires no additional power supply and instead relies on automatic heat transmission. Second, the issue of depriming in a MCPL was effectively controlled, the endurance of MCPL for the depriming problem can be executed by yielding input heat fluxes of 185.2 W/cm2 at an evaporator temperature of 165 °C, thus revealing that this model provides excellent cooling performance. Third, the effective operation range was determined and its successful operation was confirmed for MCPL. The ease of starting up increased with the temperature of the reservoir. Finally, two-phase tension that originated in the groove structures in the evaporator and condenser was confirmed to control the movement of the fluids throughout the system and verified to be effective in improving cooling efficiency.  相似文献   
137.
A facile route and the related mechanism for forming sixfold core-shell hierarchical structure with well-defined anisotropic three-dimensional arrays have been described. The regularity and symmetry of hierarchical structures prepared by annealing Zn microtips are superior to the random nanostructure arrays formed in general vapor system reported in the literature. Owing to the distinct stress distribution on the topography of microtips during annealing, the mechanism for growing branched zinc oxide (ZnO) nanowhiskers is related to the relaxation of stress. In addition, the self-assembled hierarchical structures with naturally good contact results in a lowered energy barrier between Zn metal and ZnO semiconductor, which in turn gives a much better emission property.  相似文献   
138.
High-resolution X-ray measurements near a nuclear resonance reveal the complete vibrational spectrum of the probe nucleus. Because of this, nuclear resonance vibrational spectroscopy (NRVS) is a uniquely quantitative probe of the vibrational dynamics of reactive iron sites in proteins and other complex molecules. Our measurements of vibrational fundamentals have revealed both frequencies and amplitudes of 57Fe vibrations in proteins and model compounds. Information on the direction of Fe motion has also been obtained from measurements on oriented single crystals, and provides an essential test of normal mode predictions. Here, we report the observation of weaker two-quantum vibrational excitations (overtones and combinations) for compounds that mimic the active site of heme proteins. The predicted intensities depend strongly on the direction of Fe motion. We compare the observed features with predictions based on the observed fundamentals, using information on the direction of Fe motion obtained either from DFT predictions or from single crystal measurements. Two-quantum excitations may become a useful tool to identify the directions of the Fe oscillations when single crystals are not available.  相似文献   
139.
In this paper we define sheaf spaces of BL-algebras (or BL-sheaf spaces), we study completely regular and compact BL-sheaf spaces and compact representations of BL-algebras and, finally, we prove that the category of non-trivial BL-algebras is equivalent with the category of compact local BL-sheaf spaces. Mathematics Subject Classification (2000):08A72, 03G25, 54B40, 06F99, 06D05  相似文献   
140.
Zusammenfassung Es wird ein spezielles Verfahren zur Probenvorbereitung beschrieben, durch welches Verluste an Quecksilber weitgehend vermieden werden. Die invers-voltammetrische Bestimmung des Quecksilbers erfolgt an einer rotierenden Goldelektrode. Durch Messung der Signale der 2. harmonischen Welle der Wechselstrom-Voltammetrie werden Störungen der Grundlinie weitgehend eliminiert.
AC-2 anodic stripping voltammetric determination of mercury in urine
Summary A special method for sample preparation avoiding losses of mercury is described. A rotating gold electrode is used for the anodic-stripping voltammetric determination of mercury. In order to suppress base-line disturbances, the signal of the 2nd harmonic wave of AC-voltammetry is employed.
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