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31.
The discrimination of the angular velocity of ventrodorsal and dorsoventral movement of an acoustic image was studied in nine test subjects. The experiments were performed using an apparent movement produced by consecutive activation of loudspeakers located along an arc in the vertical plane. The differential thresholds were measured by the minimum increment method. As the velocity of an acoustic image movement in opposite directions increased, the values of its mean absolute differential thresholds increased monotonically. Regression lines plotted by linear approximation of these values did not differ significantly. 相似文献
32.
L. G. Akhmetzyanova A. A. Saveliev S. Yu. Selivanovskaya 《Contemporary Problems of Ecology》2012,5(6):554-558
This paper presents an algorithm for determining the content of oil products in remediated soil that is safe for plants and microorganisms. The algorithm includes laboratory modeling of the remediation of soil samples that contain different amounts of soil products, determination of the biological parameters that provide the integral characterization of the soil state in these samples, and analysis of the results on the basis of odds-ratio statistics, which allows one to determine the content of oil products, starting from which the state of an oil-contaminated soil has no significant difference from a control soil. 相似文献
33.
Ai‐Xin Song Chen‐Jie Zhou Xiao Guan Kong‐Hung Sze Hong‐Yu Hu 《Protein science : a publication of the Protein Society》2010,19(5):1104-1109
DC‐UbP/UBTD2 is a ubiquitin (Ub) domain‐containing protein first identified from dendritic cells, and is implicated in ubiquitination pathway. The solution structure and backbone dynamics of the C‐terminal Ub‐like (UbL) domain were elucidated in our previous work. To further understand the biological function of DC‐UbP, we then solved the solution structure of the N‐terminal domain of DC‐UbP (DC‐UbP_N) and studied its Ub binding properties by NMR techniques. The results show that DC‐UbP_N holds a novel structural fold and acts as a Ub‐binding domain (UBD) but with low affinity. This implies that the DC‐UbP protein, composing of a combination of both UbL and UBD domains, might play an important role in regulating protein ubiquitination and delivery of ubiquitinated substrates in eukaryotic cells. 相似文献
34.
35.
O. B. Kazakova E. F. Khusnutdinova G. A. Tolstikov K. Yu. Suponitsky 《Russian Journal of Bioorganic Chemistry》2010,36(4):512-515
New olean-18(19)-ene triterpenoids were effectively synthesized by the interaction of allobetulin or its acetate with phosphorous
oxychloride in refluxing pyridine. The structures of the synthesized 17-chloromethyloleane-18(19)-enes were confirmed by NMR
spectroscopy and X-ray analysis. 相似文献
36.
37.
Fast, efficient and selective deprotection of the tert-butoxycarbonyl (Boc) group of various amino acids and peptides was achieved by using hydrogen chloride (4 m) in anhydrous dioxane solution for 30 min at room temperature. In the cases studied in our laboratory, this protocol provided superior selectivity to deprotect Nalpha-Boc groups in the presence of tert-butyl esters and tert-butyl ethers, including thio-tert-butyl ethers, but not phenolic tert-butyl ethers. 相似文献
38.
Peng Chen Pranjal Swarup Wojciech Michal Matkowski Adams Wai Kin Kong Su Han Zhihe Zhang Hou Rong 《Ecology and evolution》2020,10(7):3561-3573
- As a highly endangered species, the giant panda (panda) has attracted significant attention in the past decades. Considerable efforts have been put on panda conservation and reproduction, offering the promising outcome of maintaining the population size of pandas. To evaluate the effectiveness of conservation and management strategies, recognizing individual pandas is critical. However, it remains a challenging task because the existing methods, such as traditional tracking method, discrimination method based on footprint identification, and molecular biology method, are invasive, inaccurate, expensive, or challenging to perform. The advances of imaging technologies have led to the wide applications of digital images and videos in panda conservation and management, which makes it possible for individual panda recognition in a noninvasive manner by using image‐based panda face recognition method.
- In recent years, deep learning has achieved great success in the field of computer vision and pattern recognition. For panda face recognition, a fully automatic deep learning algorithm which consists of a sequence of deep neural networks (DNNs) used for panda face detection, segmentation, alignment, and identity prediction is developed in this study. To develop and evaluate the algorithm, the largest panda image dataset containing 6,441 images from 218 different pandas, which is 39.78% of captive pandas in the world, is established.
- The algorithm achieved 96.27% accuracy in panda recognition and 100% accuracy in detection.
- This study shows that panda faces can be used for panda recognition. It enables the use of the cameras installed in their habitat for monitoring their population and behavior. This noninvasive approach is much more cost‐effective than the approaches used in the previous panda surveys.
39.
L. A. Piruzyan V. A. Sukhanov E. V. Kalinina T. Yu. Fedorova A. N. Saprin 《Biology Bulletin》2002,29(2):115-119
We studied intraspecific features of the main enzymes of metabolism and detoxication of xenobiotics on mice (eight inbred lines) and rats (five lines) for estimation of possible variants of complete or incomplete metabolic equality. Significant genetically determined intraspecific differences for activities of the enzymes of metabolism and detoxication of xenobiotics were described. Generalized criteria for comparison of the metabolic status were proposed on the basis of activities of the main enzymes: cytochrome P-450 (hydroxylation and epoxidation), epoxyhydrolase, glutathione-S-transferase, UDP-glucuronosyl transferase, and sulfotransferase. The proposed criteria for estimation of the metabolic parameters of an individual can serve as a basis of metabolic portraiting. 相似文献
40.