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61.
J Guan XK Zhu Y Tachibana KF Bastow A Brossi E Hamel KH Lee 《Canadian Metallurgical Quarterly》1998,6(11):2127-2131
Demethylation of colchiceinamide (2) and its analogues (3-10) afforded a novel class of mammalian DNA topoisomerase II inhibitors (2a-10a) without displaying tubulin inhibitory activity. All target compounds inhibited the catalytic activity of topoisomerase II at drug concentrations at 100 microM. An in vitro cytotoxicity assay indicated that compounds 3a and 8a were strong and tissue-selective cytotoxic agents against the MCF-7 breast cancer cell line (IC50 = 0.36 and 0.48 microgram/mL, respectively) and the CAKI-1 renal cancer cell line (IC50 = 0.72 and 0.96 microgram/mL, respectively). 相似文献
62.
The measuring method proposed by Keene and Quinn has been further developed to investigate 3-component slags of the system CaO-SiO2-Al2O3 at temperatures of 800–1600°C in the wavelength range of 550 to 850 nm. The results are presented with the aid of the complex refraction index, which embodies all information on the optical properties of the slags investigated, including photon conductivity and thermal emissivity. Comparison of the photon conductivities determined shows good agreement with the corresponding values of various types of glass cited in literature. The discontinuous pattern of the phonon conductivity curve in the melting range of 40% CaO-40% SiO2-20% Al2O3 slag, as already found by Gammal and Li, is also evident from the data of the present investigation. 相似文献
63.
Simulation eines pfannenmetallurgischen Stahlraffinationsverfahrens unter Verwendung von Cer-Mischmetall, einer Raffinationsschlacke und Argonspülung zur Reinheitsgradverbesserung. Darstellung typischer nichtmetallischer Einschlüsse. Aufzeigen der erzielten Zähigkeitsverbesserungen und der Verringerung der Zähigkeitsanisotropie. 相似文献
64.
Mandeep M. Sahani Tarek M. Daoud Ramin Sam Jerry Andrews Yuk Lun Cheng Carl M. Kjellstrand Todd S. Ing 《Hemodialysis international. International Symposium on Home Hemodialysis》2001,5(1):92-96
An aggressive dialysis in a grossly azotemic patient, especially one with severe metabolic acidosis, can lead to dialysis disequilibrium syndrome (DDS). Mild forms present as nausea, vomiting, restlessness, and headache. Severe manifestations include seizures, obtundation, coma, and even death. This clinical picture is caused by cerebral edema induced by one or more of the following mechanisms:
- 相似文献
65.
In this paper a procedure for analytical prediction of joint shear strength of interior beam-column joints, strengthened with externally bonded fiber-reinforced polymer (FRP) sheets, has been presented. The procedure is based on the formulation available in the literature. To implement the available formulation for shear capacity prediction a computer program has been developed. Using this program shear capacity of the joint and joint shear stress variation at various stages of loading have been predicted and compared with experimental observations; presented in Part I of this study. Predictions show good agreement with experimental test results. The formulation is further extended to predict diagonal tensile stresses in the joint. The effectiveness of FRP quantity on joint shear strength and on various strains has been studied on parametric basis. It is observed that even a low quantity of FRP can enhance shear capacity of the joint significantly and its effectiveness can be further increased if debonding is suppressed (e.g., through mechanical anchorages). Effect of column axial load on shear strength of the joint has also been studied. It is observed that axial load increases the confinement of the joint core, which in turn increases the shear capacity of the joint. 相似文献
66.
Trenchless technology (TT) includes a large family of methods utilized for installing and rehabilitating underground utility systems with minimal surface disruption and destruction resulting from conventional excavation. Productivity of TT techniques is affected by a number of subjective factors that need to be evaluated. A productivity index (PI) model is developed in order to represent this subjective effect in refining productivity assessment. The analytic hierarchy process and fuzzy logic are used to develop the proposed PI model that relies on the actual performance of 12 subfactors under three main categories: management, environmental, and physical conditions. The developed PI model resulted in PI equal to 0.7323 and 0.7251 for microtunneling and horizontal directional drilling (HDD) projects, respectively. Multiattribute decision support system software is developed to determine the PI for a specific TT technique using Visual Basic. The PI model is tested, which shows reasonable results. This research is relevant to both industry practitioners and researchers. It provides practitioners with a model that justifies their productivity calculation by quantifying subjective factors effect, which will affect their schedule and cost estimation for trenchless projects. In addition, it provides researchers with the development methodology for the PI model. 相似文献
67.
Tarek Hattab Cedric Jamet Cherif Sammari Soumaya Lahbib 《International journal of remote sensing》2013,34(20):7163-7177
Few studies have focused on the use of ocean colour remote sensors in the Gulf of Gabes (southeastern Tunisia). This work is the first study to evaluate the ocean colour chlorophyll-a product in this area. Chlorophyll-a concentrations were measured during oceanographic cruises performed off the Gulf of Gabes. These measurements were used to validate satellite data acquired from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite. First, two atmospheric correction procedures (standard and shortwave infrared) were tested to derive the remote-sensing reflectance, and then a comparison between two bio-optical (OC3M and MedOC3) algorithms were realized using the in situ measurements. Both atmospheric correction procedures gave similar results when applied to our study area indicating that most pixels were non-turbid. The comparison between bio-optical algorithms shows that using the regional bio-optical algorithm MedOC3 improves chlorophyll-a estimation in the Gulf of Gabes for the low values of this parameter. 相似文献
68.
Network synchronization plays a significant role
in transmitting multimedia objects over computer networks.
Even packets from a single channel must be synchronized due to
the problems in a packet switching environment, such as
network jitter, frequency, and time offsets. We present an
algorithm that determines the set of packets generated
periodically by various participants arriving at a node. The basic
advantage of the proposed algorithm is that the receiver
estimates the reference times (expected arrival times of the
packets) and achieves synchronization, without knowledge of the
packet delays.
The
accuracy is improved and the complexity is reduced by
predicting the time/frequency offsets between the clocks at the
source and the mixer. The error is calculated by the Chernoff
bound, demonstrated by simulation, and shown to be acceptable
in practical applications. 相似文献
69.
R. Gopi R. Sheeba K. Anguraj T. Chelladurai Haya Mesfer Alshahrani Nadhem Nemri Tarek Lamoudan 《计算机系统科学与工程》2023,44(2):1567-1582
Rapid increase in the large quantity of industrial data, Industry 4.0/5.0 poses several challenging issues such as heterogeneous data generation, data sensing and collection, real-time data processing, and high request arrival rates. The classical intrusion detection system (IDS) is not a practical solution to the Industry 4.0 environment owing to the resource limitations and complexity. To resolve these issues, this paper designs a new Chaotic Cuckoo Search Optimization Algorithm (CCSOA) with optimal wavelet kernel extreme learning machine (OWKELM) named CCSOA-OWKELM technique for IDS on the Industry 4.0 platform. The CCSOA-OWKELM technique focuses on the design of feature selection with classification approach to achieve minimum computation complexity and maximum detection accuracy. The CCSOA-OWKELM technique involves the design of CCSOA based feature selection technique, which incorporates the concepts of chaotic maps with CSOA. Besides, the OWKELM technique is applied for the intrusion detection and classification process. In addition, the OWKELM technique is derived by the hyperparameter tuning of the WKELM technique by the use of sunflower optimization (SFO) algorithm. The utilization of CCSOA for feature subset selection and SFO algorithm based hyperparameter tuning leads to better performance. In order to guarantee the supreme performance of the CCSOA-OWKELM technique, a wide range of experiments take place on two benchmark datasets and the experimental outcomes demonstrate the promising performance of the CCSOA-OWKELM technique over the recent state of art techniques. 相似文献
70.
Tarek Medkour Andrew T. Walden 《Signal Processing, IEEE Transactions on》2007,55(3):881-888
Complex-valued Gaussian distributions occur frequently in signal processing. We derive a simple statistic, independent of any complex-valued correlation, for testing for the equality of variances using a sample drawn from such a bivariate distribution. The percentage points of the distribution are easy to compute. The power of the test is determined and shown to be high even for very small sample sizes when the variables are highly correlated. The new test is used to determine whether the spectral power associated with an ultralow-frequency wave in the solar magnetic field is equal at two different observing spacecraft 相似文献