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1.
A planar coupled inductor having sandwich coil structure is fabricated using MEMS microfabrication techniques. The structure of the inductor coil is designed to achieve high coupling and high winding number with a relatively small coil area. In this work, the structure is fabricated by bonding two planar on-chip coil fabricated on two different substrates. This method can replace the conventional via connections that cause various problems in output pads interconnection. The functionality of the fabricated device was tested, while the basic characteristics of the fabricated coil were measured at wide range of operating frequency using cascade GSG probe and compared with the simulation. For measurements up to 1?GHz, three resonance frequencies, inductance of 35?nH and resistance of as low as 25?Ω were observed. The results show that the proposed technique is a promising alternative method for fabricating a simple and cost effective 3-D coupled inductors. 相似文献
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Rudrappa T Bonsall J Gallagher JL Seliskar DM Bais HP 《Journal of chemical ecology》2007,33(10):1898-1918
Phragmites australis is considered the most invasive plant in marsh and wetland communities in the eastern United States. Although allelopathy
has been considered as a possible displacing mechanism in P. australis, there has been minimal success in characterizing the responsible allelochemical. We tested the occurrence of root-derived
allelopathy in the invasiveness of P. australis. To this end, root exudates of two P. australis genotypes, BB (native) and P38 (an exotic) were tested for phytotoxicity on different plant species. The treatment of the
susceptible plants with P. australis root exudates resulted in acute rhizotoxicity. It is interesting to note that the root exudates of P38 were more effective
in causing root death in susceptible plants compared to the native BB exudates. The active ingredient in the P. australis exudates was identified as 3,4,5-trihydroxybenzoic acid (gallic acid). We tested the phytotoxic efficacy of gallic acid on
various plant systems, including the model plant Arabidopsis thaliana. Most tested plants succumbed to the gallic acid treatment with the exception of P. australis itself. Mechanistically, gallic acid treatment generated elevated levels of reactive oxygen species (ROS) in the treated
plant roots. Furthermore, the triggered ROS mediated the disruption of the root architecture of the susceptible plants by
damaging the microtubule assembly. The study also highlights the persistence of the exuded gallic acid in P. australis’s rhizosphere and its inhibitory effects against A. thaliana in the soil. In addition, gallic acid demonstrated an inhibitory effect on Spartina alterniflora, one of the salt marsh species it successfully invades.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
C Bais B Santomasso O Coso L Arvanitakis EG Raaka JS Gutkind AS Asch E Cesarman MC Gershengorn EA Mesri MC Gerhengorn 《Canadian Metallurgical Quarterly》1998,391(6662):86-89
The Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8) is a gamma-2 herpesvirus that is implicated in the pathogenesis of Kaposi's sarcoma and of primary effusion B-cell lymphomas (PELs). KSHV infects malignant and progenitor cells of Kaposi's sarcoma and PEL, it encodes putative oncogenes and genes that may cause Kaposi's sarcoma pathogenesis by stimulating angiogenesis. The G-protein-coupled receptor encoded by an open reading frame (ORF 74) of KSHV is expressed in Kaposi's sarcoma lesions and in PEL and stimulates signalling pathways linked to cell proliferation in a constitutive (agonist-independent) way. Here we show that signalling by this KSHV G-protein-coupled receptor leads to cell transformation and tumorigenicity, and induces a switch to an angiogenic phenotype mediated by vascular endothelial growth factor, an angiogenesis and Kaposi's-spindle-cell growth factor. We find that this receptor can activate two protein kinases, JNK/SAPK and p38MAPK, by triggering signalling cascades like those induced by inflammatory cytokines that are angiogenesis activators and mitogens for Kaposi's sarcoma cells and B cells. We conclude that the KSHV G-protein-coupled receptor is a viral oncogene that can exploit cell signalling pathways to induce transformation and angiogenesis in KSHV-mediated oncogenesis. 相似文献
4.
PURPOSE: To determine whether (D)-penicillamine is effective in reducing hepatic oxalate production and urinary oxalate excretion. MATERIALS AND METHODS: (D)-Penicillamine was administered orally to rats to determine its effect on urinary oxalate excretion and used in isolated rat hepatocytes to investigate the effect of (D)-penicillamine on oxalate production from glycolate. Studies involving hepatic aminotransferases and hepatocytes isolated from (D)-penicillamine treated rats were used to clarify the discrepancy between the in vitro and in vivo results. RESULTS: In hepatocytes (D)-penicillamine lead to a significant reduction in oxalate production from glycolate. In vivo however. (D)-penicillamine led to a significant increase in urinary oxalate excretion and a decrease in plasma aminotransferase activity. Hepatic aminotransferases are involved in diverting oxalate precursors from oxalate production. In vitro, (D)-penicillamine was shown to inhibit hepatic aminotransferases. Hepatocytes isolated from (D)-penicillamine-treated rats produced significantly more oxalate than controls. CONCLUSIONS: These results indicate that (D)-penicillamine increases hepatic oxalate production and urinary oxalate excretion. (D)-penicillamine therefore has no therapeutic potential for reducing endogenous oxalate production and urinary oxalate excretion. Moreover, in conditions such as Wilson's Disease which is often associated with hypercalcuria, its use may be contraindicated. 相似文献
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Marenco F Santacesaria V Bais AF Balis D di Sarra A Papayannis A Zerefos C 《Applied optics》1997,36(27):6875-6886
We present the results of the aerosol measurements carried out over the Aegean Sea during the Photochemical Activity and Solar Ultraviolet Radiation campaign held in Greece during June 1996. Simultaneous observations performed with a lidar and a double-monochromator spectrophotometer allowed us to retrieve the optical depth, the Angstr?m coefficient, and the backscatter-to-extinction ratio. The Sun photometric data can be used to improve quantitative aerosol measurements by lidar in the Planetary Boundary Layer. Systematic errors could arise otherwise, because the value of the backscatter-to-extinction ratio has to be supplied. Instead this ratio can be retrieved experimentally by use of an iterative solution of the lidar equation. 相似文献
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Harsh Pal Bais BS Dattatreya GA Ravishankar 《Journal of the science of food and agriculture》2003,83(8):769-774
Hairy root cultures of Cichorium intybus L produced volatile aromatic compounds under the influence of fungal elicitors. It was observed that the intensity of the production of volatile aromatic compounds in the hairy root cultures of C intybus with 10 ml l?1 media filtrate (MF) of Phytopthora parasitica var nicotiana reached a maximum on the 21st day, as seen by a quantitative flavour profiling method. It was noted that, during the time course, treatment with 10 ml l?1 MF of P parasitica to the MS basal liquid medium containing hairy root cultures of chicory resulted in changed root morphology with cell wall thickening and shear. The components of the volatile aromatic compounds were identified as a propyl isovalerate, undecanal, nonanol, isoamyl nonanoate and 2‐decene‐1‐ol. The mass spectra of all these compounds matched well with the NIST/EPA/NIH library and by comparing with the Kovats index of volatile compounds. The major fruity note was due to the presence of two of the major volatile components, namely propyl isovalerate and isoamyl nonanoate, which were also produced at higher concentration on day 21. This response of chicory hairy root cultures to the fungal elicitor producing volatile aromatic compounds would imply eco‐physiological functions, possibly for plant defence system. Copyright © 2003 Society of Chemical Industry 相似文献
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Pratibha Tripathi Poonam C. Singh Aradhana Mishra Puneet S. Chauhan Sanjay Dwivedi Ritu Thakur Bais Rudra Deo Tripathi 《Clean Technologies and Environmental Policy》2013,15(4):541-550
Environmental awareness has resulted in development of regulatory measures that aim to straighten past mistakes and protect the environment from future contamination and exploitation. However, much consideration and research needs to go into the decision-making process for an effective clean up of a particular contaminated site. Each technology developed has its advantages and limitations for the treatment of specific contaminants. Bioremediation and phytoremediation in association with microbes are innovative technologies having a potential to alleviate numerous environmental pollution problems. Owing to its dominant presence in contaminated sites, the application of the fungi in bioremediation is well documented. The genus Trichoderma is genetically very diverse with a number of capabilities among different strains with agricultural and industrial significance. It is also tolerant to a range of recalcitrant pollutants including heavy metals, pesticides, and polyaromatic hydrocarbons. This review presents an updated overview of application of Trichoderma for biological or phytobial remediation of environmental contaminants. 相似文献
10.
To quantify the effect of ambient temperature on the voltage signal of Solar Light UV-Biometers, spectral response functions of two instruments were determined in the laboratory under various external temperature conditions. Despite the biometer's internal temperature stabilization, a temperature increase of 20 degrees C at the outside of an instrument's housing resulted in a reduction of the instrument's spectral response by as much as 10% in the UVB range and by as much as a factor of 2 in the UVA range, depending on the individual instrument and on its internal relative humidity. The significance of this effect for outdoor measurements is demonstrated by data from an intercomparison campaign of erythemal radiometers in Thessaloniki, Greece, organized by the Laboratory of Atmospheric Physics (Aristotle University of Thessaloniki), the Cooperation in Science and Technology (European Commission), and the World Meteorological Organization. On 16 September 1999, 12 of 16 Solar Light Biometers showed significant diurnal variation in their sensitivity (as much as 10% for some individual instruments), which can be explained through a heating of the instruments' housings due to direct solar radiation. 相似文献