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Substrate Effects (substrate + effects)
Selected AbstractsThe Morphology and Dynamics of Substrate Effects on Spinodal Decomposition in Binary Mixtures with Short-Range PotentialMACROMOLECULAR THEORY AND SIMULATIONS, Issue 3 2006Li-Tang Yan Abstract Summary: The SDSD of binary mixture with short-range potential is numerically simulated in 3D by cell dynamic system (CDSs), focusing on the phase morphology and dynamics in the parallel cross-sections. The formation mechanism and growth law of the wetting layer are analyzed taking thermal noise effects into account. The simulated results show that the phase inversion in the parallel cross-sections can be observed near the substrate interface. Without thermal noise, the growth law of the wetting layer is simply logarithmic. However, when the strength of thermal noise is large enough, the LS growth law can be found for a short-range surface field. The results demonstrate that thermal noise can increase the extent of phase separation and lead to a transformation between partial and complete wetting for the substrate interface. The evolution of the phase in the parallel cross-sections obeys the LS growth law and is self-similar regardless of the effects of thermal noise. Simulated pattern evolution at different values of z at ,,=,1,000 with G,=,0. [source] Mrp2 modulates the activity of chloride channels in isolated hepatocytesHEPATOLOGY, Issue 1 2002Xinhua Li Adenosine triphosphate binding cassette family transport proteins are important organic ion transporters in hepatocytes but these molecules may also exhibit other functions. In the present study we have measured the effects of substrates of the canalicular organic ion transporter multidrug resistance associated protein 2 (Mrp2) on chloride channel activation and cell volume regulation. We found that substrates such as leukotriene D4, 17-,-estradiol glucuronide, and the leukotriene inhibitor MK-571 accelerated the activation of chloride channels by cell swelling and activated chloride channels in cytokine-pretreated hepatocytes. Two conjugated estrogens that are not Mrp2 substrates did not produce this effect. Hepatocytes derived from a strain of transport-deficient rats (TR,), which lack Mrp2 expression, showed none of these substrate effects. Coincident with their ability to activate channels, the Mrp2 substrates increased the rate of volume regulatory decrease by approximately 50% (P < .01), confirming that enhanced channel activation under this condition stimulated volume regulation. In TR-hepatocytes the Mrp2 substrate had no effect on volume regulation. In conclusion, Mrp2 plays a role in regulation of chloride channel function by reducing the lag time necessary for channel activation and consequently accelerating the process of cell volume regulation. Substrates of Mrp2 affect the ability of the protein to interact with chloride channels. These findings represent an alternative function of Mrp2 in hepatocytes. [source] Effects of Artificial Substrate and Stocking Density on the Nursery Production of Pacific White Shrimp Litopenaeus vannameiJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2004Komarey R. K. Moss Nursery production may be enhanced by the addition of artificial substrate to increase the surface area upon which shrimp graze and to serve as refuge. The objective of this study was to assess the effects of the artificial substrate, AquaMatsTM, on the performance of postlarval Pacific white shrimp Litopenaeus vannamei stocked at three densities. Eighteen 230-L tanks were stocked with 10-d postlarvae (mean weight < 0.01 g). Six treatments were evaluated and consisted of shrimp stocked at three densities (778 shrimp/m2, 1,167 shrimp/ m2, and 1,556 shrimp/m2) with and without access to artificial substrate. Shrimp in all treatments received a commercial diet ad libitum. After 6 wk, shrimp were harvested from each nursery tank, counted, and batch weighed. Mean final weight, survival, production, feed conversion ratio, and water quality parameters were analyzed by 2-way ANOVA. There were highly significant (P < 0.001) density and substrate effects on final weight, but there was no significant interaction effect. Final weight was 26.0, 17.4, and 34.5% greater in treatments with substrate than without substrate when stocked at 778, 1,167, and 1,556 shrimp/m2, respectively. There was no significant density, substrate, or interaction effect on survival or water quality. Mean survival was ± 89.1% for all treatments. Increased shrimp growth in the presence of added substrate was likely due to the availability of attached particulate organic matter on the AquaMatsTM that served as an additional food source. Results from this study indicate that artificial substrate can be used to mitigate the potential negative effects of high stocking density on growth of L. vannamei in nursery systems. [source] Micromachined CMOS E-band bandpass coplanar filtersMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2008Pen-Li Huang Abstract In this work, E-band CMOS coplanar filters, whose initial design is made according to quasi- TEM-approximation-based analytical models, are implemented. To study the substrate effects, the CMOS-compatible inductively coupled-plasma (ICP) deep trench technology is used to selectively remove the silicon underneath the filter completely. For the filter with top metal thickness of 0.93 ,m after the backside ICP etching, the results show that the input matching bandwidth, i.e. S11 below ,10 dB, moves from lower 39.8,81.4 GHz-band to higher 55.9,94.1 GHz-band, and the 3-dB bandwidth of S21 moves from lower 43.5,76.3 GHz-band to higher 54.5,93.3 GHz-band. In addition, a 4.67 dB improvement [from ,8.86 dB (at 58.5 GHz) to ,4.19 dB (at 74.5 GHz)] in peak S21 was achieved. These results show that for the design of passive coplanar devices in the E-band, the quasi-TEM- approximation-based analytical models can be used and the backside ICP etching is effective to reduce the substrate loss and parasitic capacitance. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 3123,3125, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23873 [source] An analysis of substrate effects on transmission-lines for millimeter-wave CMOS RFIC applicationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 2 2008Jin-Fa Chang Abstract A set of transmission lines (TLs) for millimeter-wave (MMW) CMOS RFIC applications was implemented in a standard 0.18 ,m CMOS technology and then postprocessed by CMOS-compatible inductively-coupled plasma (ICP) etching, which removed the silicon underneath the TLs completely. TL parameters such as characteristic impedance ZC, attenuation constant ,, phase constant ,, effective permittivity ,eff, minimum noise figure (NFmin), parallel capacitance/conductance C/G, and series inductance/resistance L/R, as a function of frequency were extracted. It was found that ,, ,eff, NFmin, C, and G were greatly improved after silicon removal. The state-of-the-art performances of the on-chip TLs-on-air suggest that they are very suitable for application to realize ultralow-noise MMW CMOS RFICs. Besides, the CMOS-compatible backside ICP etching technique is very promising for MMW system-on-a-chip applications. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 319,324, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23055 [source] The Effects of Doubling Limestone Sand Applications in Two Acidic Southwestern Pennsylvania StreamsRESTORATION ECOLOGY, Issue 1 2005A.L. Keener Abstract We studied the effects of limestone sand additions in Bear and Rock runs, two chronically and episodically acidified streams in southwestern Pennsylvania, U.S.A. Linn Run, a nearby episodically acidified stream, served as a reference stream. Our objectives were to evaluate the effects of doubling recommended limestone sand amounts on water quality and macroinvertebrates on Bear and Rock runs and to assess substrate changes resulting from limestone sand inundation. Approximately 23 and 6 tonnes of limestone sand were added annually to the headwaters of Bear and Rock runs, respectively, from 1999 to 2001. In 2002, amounts were doubled. Macroinvertebrate communities were assessed from 1999 to 2003 at points above and below the sand additions on Bear Run and Rock Run. Small, plastic substrate samplers were used to assess sand substrate effects. Doubling annual limestone sand amounts resulted in significantly improved pH and acid-neutralizing capacity; however, total dissolved aluminum increased significantly downstream (,, 0.05). Macroinvertebrate density and diversity were not significantly affected, but an increase in acid-sensitive taxa was observed at a site 3,500 m downstream. Substrate sampler data indicated a significant negative relationship between amount of sand deposited and density of macroinvertebrates. The mixed water quality and benthic macroinvertebrate results were reasonably consistent with earlier work and call into question the use of limestone sand in the restoration of chronically and episodically acidified waters. [source] Survival and growth responses of eight Everglades tree species along an experimental hydrological gradient on two tree island typesAPPLIED VEGETATION SCIENCE, Issue 4 2010Susana L. Stoffella Abstract Questions: How are the early survival and growth of seedlings of Everglades tree species planted in an experimental setting on artificial tree islands affected by hydrology and substrate type? What are the implications of these responses for broader tree island restoration efforts? Location: Loxahatchee Impoundment Landscape Assessment (LILA), Boynton Beach, Florida, USA. Methods: An experiment was designed to test hydrological and substrate effects on seedling growth and survivorship. Two islands , a peat and a limestone-core island representing two major types found in the Everglades , were constructed in four macrocosms. A mixture of eight tree species was planted on each island in March of 2006 and 2007. Survival and height growth of seedlings planted in 2006 were assessed periodically during the next two and a half years. Results: Survival and growth improved with increasing elevation on both tree island substrate types. Seedlings' survival and growth responses along a moisture gradient matched species distributions along natural hydrological gradients in the Everglades. The effect of substrate on seedling performance showed higher survival of most species on the limestone tree islands, and faster growth on their peat-based counterparts. Conclusions: The present results could have profound implications for restoration of forests on existing landforms and artificial creation of tree islands. Knowledge of species tolerance to flooding and responses to different edaphic conditions present in wetlands is important in selecting suitable species to plant on restored tree islands [source] | ||||||||||