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231.
Identification of Lophius budegassa(black‐bellied angler) and L. piscatorius(angler) (Lophiiformes) was carried out on the amplification of a 486 bp tRNAGlu/cytochrome b segment using the polymerase chain reaction (PCR). Direct DNA sequencing of 6 PCR products was carried out. Six restriction endonucleases (AluI, CfoI, HaeIII, HinfI, Mae, and ScrFI) with different species‐specific restriction fragment length polymorphism (RFLP) were selected. Digestions of PCR products from 30 individuals showed no intraspecific polymorphism. Double digestions (CfoI and HinfI, and HaeIII and ScrFI) were simpler and more rapid than single digestions. This technique is suitable for distinguishing tails of both Lophius species. 相似文献
232.
Accuracy of approximations in MOSFET charge models 总被引:2,自引:0,他引:2
This paper analyzes the results of common approximations made in MOSFET charge modeling. The basis for the comparison is a charge-sheet model that is valid in all regions of operation. We show that proper modeling of surface potential as a function of position along the channel is more important for capacitance coefficient modeling accuracy than partitioning of inversion charge between source and drain. In addition, we show that there is a numerical error in previous charge-sheet formulations, and provide a solution for this problem 相似文献
233.
Croon J.A. Rosmeulen M. Decoutere S. Sansen W. Maes H.E. 《Solid-State Circuits, IEEE Journal of》2002,37(8):1056-1064
In this paper, a physics-based mismatch model is presented. It is demonstrated on a 0.18-/spl mu/m technology that a simple mismatch model can still be used to characterize deep-submicron technologies. The accuracy of the model is examined and found to be within 20% in the strong inversion region. Bulk bias dependence is modeled in a physical way. To extract the mismatch parameters, a weighted fit is introduced. It is shown that the width and length dependence of the mismatch parameters is given by the Pelgrom model. 相似文献
234.
The early history of the IEEE Microwave Theory and Techniques Society (IEEE MTT-S) is summarized since its founding in 1952, and all administrative committee members and presidents are listed. Some of the more recent changes resulting from growth and multinational participation are described. Publications are discussed with editors listed for this Transactions, the IEEE Microwave and Wireless Components Letters, the IEEE Microwave Newsletter, and IEEE Microwave Magazine. The chronological evolution of the IEEE MTT-S's awards is presented, including a listing of all award winners. Distinguished lecturers and microwave symposia sites and chairpersons are also discussed. Early technology trends are described 相似文献
235.
Yuhua Cheng Chih-Hung Chen Matloubian M. Deen M.J. 《Electron Devices, IEEE Transactions on》2002,49(3):400-408
High-frequency (HF) AC and noise modeling of MOSFETs for radio frequency (RF) integrated circuit (IC) design is discussed. A subcircuit RF model incorporating the HF effects of parasitics is presented. This model is compared with the measured data for both y parameter and fT characteristics. Good model accuracy is achieved against measurements for a 0.25 μm RF CMOS technology. The HF noise predictivity of the model is also examined with measured data. Furthermore, a methodology to extract the channel thermal noise of MOSFETs from HF noise measurements is presented. By using the extracted channel thermal noise, any thermal noise models can be verified directly. Several noise models including the RF model discussed in this paper have been examined, and the results show that the RF model can predict the channel thermal noise better than the other models 相似文献
236.
Wang J.R. Racette P. Tiesky M.E. Manning W. 《Geoscience and Remote Sensing, IEEE Transactions on》2002,40(6):1220-1229
The airborne Millimeter-wave Imaging Radiometer (MIR) measurements conducted over the Midwest region of the continental United States during January/February 1997 and over the Alaska-Arctic region during May 1998 are used to estimate column water vapor W<0.8 g/cm/sup 2/ under a clear sky. On board the same aircraft are two other instruments, the Cloud Lidar System (CLS) and MODerate-resolution Imaging Spectrometer (MODIS) Airborne Simulator (MAS), which provide cloud cover information and independent measurements of W, respectively. The MIR-estimated W values are compared and found to be in very good agreement with those measured by rawinsondes at near concurrence. A close correlation is found between the MIR-estimated W and that estimated from the MAS near-IR reflectance ratios. Water surface emissivities at several MIR frequencies are obtained in the process of the W retrieval from several flights over the Midwest lakes. These estimated emissivities compared favorably with values calculated for a calm water surface, which are based on a di-electric permittivity model and MAS-measured surface temperatures. The results from all comparisons strongly demonstrate the soundness of the technique for estimating W. 相似文献
237.
Depletion and hillock formation were examined in-situ in a scanning electron microscope (SEM) during electromigration of bamboo
Al interconnect segments. Hillocks formed directly at the anode ends of the segments by epitaxial addition of Al at the bottom
Al/TiN interface. Depletion occurred nonuniformly from the cathode end and stopped once the distance between the leading void
and the hillock reached the critical length for electromigration at the given current density. A modified equation for the
drift velocity is proposed, which includes the effect of nonuniform depletion and predicts that interconnects with nonuniform
depletion are more reliable than those with uniform depletion. 相似文献
238.
CA Piantadosi J Zhang ED Levin RJ Folz DE Schmechel 《Canadian Metallurgical Quarterly》1997,147(1):103-114
Delayed neurological damage after CO hypoxia was studied in rats to determine whether programmed cell death (PCD), in addition to necrosis, is involved in neuronal death. In rats exposed to either air or CO (2500 ppm), microdialysis in brain cortex and hippocampus was performed to determine the extent of glutamate release and hydroxyl radical generation during the exposures. Groups of control and CO-exposed rats also were tested in a radial maze to assess the effects of the CO exposures on learning and memory. At 3, 7, and 21 days after CO exposure brains were perfusion-fixed and hematoxylin-eosin (H&E) was used to assess injury and to select regions for further examination. DNA fragmentation was sought by examining cryosections with the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) reaction. We found significant increases in glutamate release and .OH generation during and immediately after CO hypoxia. CO-exposed rats showed learning and memory deficits after exposure associated with heterogeneous cell loss in cortex, globus pallidus, and cerebellum. The frontal cortex was affected most seriously; the damage was slight at Day 3, increased at Day 7, and persistent at Day 21 after CO exposure. TUNEL staining was positive at all three time points, and TUNEL-labeled cells were distributed similarly to eosinophilic cells. The number of cells stained by TUNEL was less than by H&E and amounted to 2 to 5% of all cell nuclei in regions of injury. Ultrastructural features of both neuronal necrosis and apoptosis also were observed readily by electron microscopy. These findings indicate that both necrosis and apoptosis (PCD) contribute to CO poisoning-induced brain cell death. 相似文献
239.
240.