1,461 research outputs found
TNFα induces Ca2+ influx to accelerate extrinsic apoptosis in hepatocellular carcinoma cells
BACKGROUND: Tumor necrosis factor-α has been proven an effective anticancer agent in preclinical studies. However, the translation of TNFα from research to clinic has been blocked by significant systemic toxicity and limited efficacy at maximal tolerated dose, which need urgently to be solved.
METHODS: The level of cytosolic Ca
RESULTS: Here, we demonstrated that TNFα induced extracellular Ca
CONCLUSIONS: Our study provides the evidence supporting a novel mechanism by which TNFα induces extracellular C
Characterization of isoprene-derived secondary organic aerosols at a rural site in North China Plain with implications for anthropogenic pollution effects
Isoprene is the most abundant non-methane volatile organic compound (VOC) and the largest contributor to secondary organic aerosol (SOA) burden on a global scale. In order to examine the influence of high concentrations of anthropogenic pollutants on isoprene-derived SOA (SOA(i)) formation, summertime PM2.5 filter samples were collected with a three-hour sampling interval at a rural site in the North China Plain (NCP), and determined for SOA(i) tracers and other chemical species. RO2+NO pathway derived 2-methylglyceric acid presented a relatively higher contribution to the SOA, due to the high-NOx (similar to 20 ppb) conditions in the NCP that suppressed the reactive uptake of RO2+HO2 reaction derived isoprene epoxydiols. Compared to particle acidity and water content, sulfate plays a dominant role in the heterogeneous formation process of SOA(i). Diurnal variation and correlation of 2-methyltetrols with ozone suggested an important effect of isoprene ozonolysis on SOA(i) formation. SOA(i) increased linearly with levoglucosan during June 10-18, which can be attributed to an increasing emission of isoprene caused by the field burning of wheat straw and a favorable aqueous SOA formation during the aging process of the biomass burning plume. Our results suggested that isoprene oxidation is highly influenced by intensive anthropogenic activities in the NCP
QoS-aware multihop routing in wireless sensor networks with power control using demodulation-and-forward protocol
Abstract
In this article, we propose a low-complexity joint power allocation and route planning algorithm for multiple antennas wireless sensor networks using dynamic programming. The sensor nodes utilize orthogonal space time block codes with demodulation-and-forward protocol. Unlike the previous work which typically optimize all the parameters, we cast this Quality-of-Service aware packet forwarding problem into two disjoint procedures: dynamic programming based route planning and subsequent adaptive power allocation. Simulation results indicate that the proposed protocol obtains comparative performance with the optimal results and significantly outperforms classical routing algorithms.</jats:p
Efficacy and safety of minimally invasive percutaneous nephrolithotomy(MPCNL) and standard channel percutaneous nephrolithotomy(SPCNL) in the treatment of kidney stones:A meta analysis
Objective: To evaluate the efficacy and safety of minimally invasive percutaneous nephrolithotomy(MPCNL) standard channel percutaneous nephrolithotomy(SPCNL) in the treatment of kidney stones. Methods: We searched pubmed, Cochrane Liabrary, CNKI, VIP , Wangfang database from January 1, 1992 to April 1, 2015. Screening of the two methods of treatment of kidney stones randomized controlled trials (RCT) and quality assessment, using revman5.2 software for statistical analysis. Results: A total of nine RCT, 1017 patients, 508 cases in MPCNL group, 509 cases in SPCNL group. The results show: the stones clearance , MPCNL group was lower than SPCNL group [OR=0.62, 95%CI(0.43, 0.91), P=0.01]; in terms of operative time, MPCNL group was longer than SPCNL group [MD = 14.23 , 95% CI (6.30, 22.16), P = 0.0004]; hospitalization time, blood loss, total complications, were no significant difference between the two group, the results are [MD = 0.88, 95% CI (-0.69 , 2.44), P = 0.27], [MD =-19.87, 95% CI (-64.36, 24.61), P = 0.38], [OR=1.28, 95%CI(0.90, 1.84), P=0.17]. Conclusion: the stone clearance rate:MPCNL group was lower than SPCNL group, the operative time of MPCNL group was longer which may affect postoperative recovery, the complications, hospital stay, blood loss, the two groups had no significant difference. So , we tend to standard channel percutaneous nephrolithotomy in the treatment of common type of kidney stones
A fast framework construction and visualization method for particle-based fluid
© 2017, The Author(s). Fast and vivid fluid simulation and visualization is a challenge topic of study in recent years. Particle-based simulation method has been widely used in the art animation modeling and multimedia field. However, the requirements of huge numerical calculation and high quality of visualization usually result in a poor computing efficiency. In this work, in order to improve those issues, we present a fast framework for 3D fluid fast constructing and visualization which parallelizes the fluid algorithm based on the GPU computing framework and designs a direct surface visualization method for particle-based fluid data such as WCSPH, IISPH, and PCISPH. Considering on conventional polygonization or adaptive mesh methods may incur high computing costs and detail losses, an improved particle-based method is provided for real-time fluid surface rendering with the screen-space technology and the utilities of the modern graphics hardware to achieve the high performance rendering; meanwhile, it effectively protects fluid details. Furthermore, to realize the fast construction of scenes, an optimized design of parallel framework and interface is also discussed in our paper. Our method is convenient to enforce, and the results demonstrate a significant improvement in the performance and efficiency by being compared with several examples
Assessment of Night-Time Lighting for Global Terrestrial Protected and Wilderness Areas
Protected areas (PAs) play an important role in biodiversity conservation and ecosystem integrity. However, human development has threatened and affected the function and effectiveness of PAs. The Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) night-time stable light (NTL) data have proven to be an effective indicator of the intensity and change of human-induced urban development over a long time span and at a larger spatial scale. We used the NTL data from 1992 to 2013 to characterize the human-induced urban development and studied the spatial and temporal variation of the NTL of global terrestrial PAs. We selected seven types of PAs defined by the International Union for Conversation of Nature (IUCN), including strict nature reserve (Ia), wilderness area (Ib), national park (II), natural monument or feature (III), habitat/species management area (IV), protected landscape/seascape (V), and protected area with sustainable use of natural resources (VI). We evaluated the NTL digital number (DN) in PAs and their surrounding buffer zones, i.e., 0–1 km, 1–5 km, 5–10 km, 10–25 km, 25–50 km, and 50–100 km. The results revealed the level, growth rate, trend, and distribution pattern of NTL in PAs. Within PAs, areas of types V and Ib had the highest and lowest NTL levels, respectively. In the surrounding 1–100 km buffer zones, type V PAs also had the highest NTL level, but type VI PAs had the lowest NTL level. The NTL level in the areas surrounding PAs was higher than that within PAs. Types Ia and III PAs showed the highest and lowest NTL growth rate from 1992 to 2013, respectively, both inside and outside of PAs. The NTL distributions surrounding the Ib and VI PAs were different from other types. The areas close to Ib and VI boundaries, i.e., in the 0–25 km buffer zones, showed lower NTL levels, for which the highest NTL level was observed within the 25–100 km buffer zone. However, other types of PAs showed the opposite NTL patterns. The NTL level was lower in the distant buffer zones, and the lowest night light was within the 1–25 km buffer zones. Globally, 6.9% of PAs are being affected by NTL. Conditions of wilderness areas, e.g., high latitude regions, Tibetan Plateau, Amazon, and Caribbean, are the least affected by NTL. The PAs in Europe, Asia, and North America are more affected by NTL than South America, Africa, and Oceania
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