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101.
The novel two-dimensional (2D) wavelet with anisotropic property and application of it has been presented. Wavelet is constructed
in the polar coordinate system to obtain anisotropic properties. A novel edge detection method has been developed with the
aid of this wavelet. This method detects gradient jump and than follows along this jump. In this way the number of calculation
for edge localization is reduced. Moreover, the presented method is able to detect all edges in an image in multi-scale together
with its spatial orientation. Proposed wavelet as well as edge extraction method seems to be new way to edge detection for
an image. 相似文献
102.
Salikhov I Hirata H Walczak T Swartz HM 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,164(1):54-59
An improved external loop resonator (ELR) used for L-band electron paramagnetic resonance (EPR) spectroscopy is reported. This improvement is achieved by shortening the parallel coaxial line. The resonant structure is formed by two single turn coils (10mm in diameter) that are connected to a parallel coaxial line. A resonance frequency of 1197 MHz and a quality factor of 466 were obtained in the absence of biological tissue and were approximately 1130 MHz and approximately 50 with a living animal, respectively. The sensitivity of the new ELR was compared to the previously developed ELR using three types of EPR samples: (1) paramagnetic material with no biological tissue, (2) paramagnetic material in a leg and in the peritoneal cavity of a dead rat, and (3) paramagnetic material in the back of an anesthetized rat. The sensitivity was 1.2-1.6 times greater in the rat and 4.2 times without tissue. 相似文献
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V. Pravdova B. Walczak D. L. Massart S. Kawano K. Toyoda R. Tsenkova 《Analytica chimica acta》2001,450(1-2):131-141
A PLS model for prediction of somatic cell count (SCC) based on near-infrared (NIR) spectra of unhomogenized milk is presented in the study. Samples of raw milk were collected from cows in the early lactation period (from 7th to 29th day after parturition). The NIR spectra were measured in the region 400–1100 nm. As reference method a fluoro-opto-electronic method was applied. Different preprocessing methods were investigated. The robust version of PLS regression was applied to handle outliers present in the dataset and the uninformative variable elimination–partial least squares (UVE–PLS) method was used to eliminate uninformative variables. The final model is acceptable for prediction of SCC in raw milk. 相似文献
105.
Chengxiang Xiang Adam Z. Weber Shane Ardo Alan Berger YiKai Chen Robert Coridan Katherine T. Fountaine Sophia Haussener Shu Hu Rui Liu Nathan S. Lewis Miguel A. Modestino Matthew M. Shaner Meenesh R. Singh John C. Stevens Ke Sun Karl Walczak 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(42):13168-13183
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Dr. Feng Zhu Sloane O'Neill Jacob Rodriguez Prof. Dr. Maciej A. Walczak 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(13):3147-3155
In this Concept article, recent advances are highlighted in the synthesis and applications of anomeric nucleophiles, a class of carbohydrates in which the C1 carbon bears a carbon–metal bond. First, the advantages of exploiting the carboanionic reactivity of carbohydrates and the methods for the synthesis of mono- and oligosaccharide stannanes are discussed. Second, recent developments in the glycosyl cross-coupling method resulting in the transfer of anomeric configuration from C1 stannanes to C-aryl glycosides are reviewed. These highly stereoretentive processes are ideally suited for the preparation of carbohydrate-based therapeutics and were demonstrated in the synthesis of antidiabetic drugs. Next, the application of the glycosyl cross-coupling method to the preparation of Se-glycosides and to glycodiversification of small molecules and peptides are highlighted. These reactions proceed with exclusive anomeric control for a broad range of substrates and tolerate carbohydrates with free hydroxyl groups. Taken together, anomeric nucleophiles have emerged as powerful tools for the synthesis of oligosaccharides and glycoconjugates and their future applications will open new possibilities to incorporate saccharides into small molecules and biologics. 相似文献
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