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1.
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.
2.
Gang Xi Xin-Chun Shen Christine Wai David R. Clemmons 《The Journal of biological chemistry》2013,288(22):15641-15653
Nox4-derived ROS is increased in response to hyperglycemia and is required for IGF-I-stimulated Src activation. This study was undertaken to determine the mechanism by which Nox4 mediates sustained Src activation. IGF-I stimulated sustained Src activation, which occurred primarily on the SHPS-1 scaffold protein. In vitro oxidation experiments indicated that Nox4-derived ROS was able to oxidize Src when they are in close proximity, and Src oxidation leads to its activation. Therefore we hypothesized that Nox4 recruitment to the plasma membrane scaffold SHPS-1 allowed localized ROS generation to mediate sustained Src oxidation and activation. To determine the mechanism of Nox4 recruitment, we analyzed the role of Grb2, a component of the SHPS-1 signaling complex. We determined that Nox4 Tyr-491 was phosphorylated after IGF-I stimulation and was responsible for Nox4 binding to the SH2 domain of Grb2. Overexpression of a Nox4 mutant, Y491F, prevented Nox4/Grb2 association. Importantly, it also prevented Nox4 recruitment to SHPS-1. The role of Grb2 was confirmed using a Pyk2 Y881F mutant, which blocked Grb2 recruitment to SHPS-1. Cells expressing this mutant had impaired Nox4 recruitment to SHPS-1. IGF-I-stimulated downstream signaling and biological actions were also significantly impaired in Nox4 Y491F-overexpressing cells. Disruption of Nox4 recruitment to SHPS-1 in aorta from diabetic mice inhibited IGF-I-stimulated Src oxidation and activation as well as cell proliferation. These findings provide insight into the mechanism by which localized Nox4-derived ROS regulates the sustained activity of a tyrosine kinase that is critical for mediating signal transduction and biological actions. 相似文献
3.
R D Goldfien P J Chen T J Kipps G Starkebaum J G Heitzmann V Radoux S Fong D A Carson 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(3):940-944
We have examined the genetic basis for the expression of a human cross-reactive idiotype (CRI) commonly found on monoclonal IgM rheumatoid factors. The CRI was identified with a monoclonal antibody (17.109) and has been localized previously to the kappa-variable region. By using the human lymphoblastoid cell line WI-L2-729-HF2, and mononuclear cells from several sources, a panel of hybridomas was generated that produced 17.109 CRI-positive Ig. A recently cloned human germ-line V kappa III gene, Humkv305, served as a probe to identify genes which were rearranged and expressed in 17.109 CRI-positive and -negative hybridomas. This probe, when hybridized to human genomic DNA under stringent conditions, identified only two to five germ-line bands. In 10 separate 17.109 CRI-positive hybridoma clones, an additional rearranged V kappa band was identified. The probe did not anneal to rearranged V kappa bands in hybridoma clones that produced kappa-chains lacking the CRI. RNA dot-blot studies provided evidence for expression of genes hybridizing to the Humkv305 probe. The results indicate that the 17.109 CRI is a serologic marker for a single V kappa gene, or a small family of closely related V kappa genes, which is identified by the Humkv305 probe. 相似文献
4.
Plant seed storage proteins were among the first proteins to be isolated (20); however, only recently, as a result of using molecular biology techniques, have the amino acid sequences of many of these proteins been determined. With the accumulation of amino acid sequence data for many vicilin-type storage proteins much has been learned concerning the location of conserved amino acid regions and other regions which can tolerate amino acid sequence variation. Combining this knowledge with recent advances in plant gene transfer technologies will allow molecular biologists to correct (by using amino acid replacement mutations) the sulfur amino acid deficiency inherent to bean seed storage proteins. The development of more nutritious soybean and common bean seeds will be of benefit to programs involving human and animal nutrition. 相似文献
5.
The steady-state kinetics of isozymes of human liver alcohol dehydrogenase (ADH) containing the beta 2 (Oriental) subunit were investigated in order to confirm the supposition [Fong, W.P., & Keung, W. M. (1987) Biochemistry (preceding paper in this issue)] that the subunits of such heterodimeric ADHs act independently and noncooperatively. The ADH isozymes alpha beta 2, beta 2 beta 2, beta 2 gamma 1, and beta 2 gamma 2 as well as gamma 1 gamma 1 were purified by chromatography on DEAE-cellulose, 4-[3-[N-(6-aminocaproyl)amino]propyl]pyrazole--Sepharose, and CM-cellulose. Their kinetics were studied at pH 9.0 with cyclohexanol since this substrate permits maximal differentiation between activities of the heterodimeric subunits. Oxidation of cyclohexanol by the homodimers beta 2 beta 2 and gamma 1 gamma 1 follows conventional Michaelis-Menten kinetics. The values of Km and kcat determined for beta 2 beta 2 and gamma 1 gamma 1 are 0.11 M and 260 min-1 and 79 microM and 45 min-1, respectively, indicating that beta 2 beta 2, like the previously studied beta 1 beta 1, has an unusually low binding affinity for cyclohexanol compared to that of the ADH isozymes formed by the combination of alpha, gamma 1, and gamma 2 chains. Cyclohexanol oxidation by the heterodimers alpha beta 2, beta 2 gamma 1, and beta 2 gamma 2 follows biphasic kinetics which can be fully accounted for by the individual subunits, one exhibiting a high and the other a low substrate-binding affinity. Eadie-Hofstee plots resolve the biphasic kinetics into two linear components, each of which yields a set of kinetic parameters.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
C N Fong H L Atwood K N Jeejeebhoy M P Charlton 《Canadian journal of physiology and pharmacology》1987,65(11):2188-2190
The effects of malnutrition on intracellular K+ activity, (alpha K)i, and membrane potential, Em, were measured by means of double-barrelled K+-selective microlectrodes in the soleus and gastrocnemius muscles of the rat. (alpha K)i and Em were measured in vivo in normal anaesthetized animals and in rats subjected to one of two diet restrictions: a 2-day fast or a long-term hypocaloric diet. In the soleus muscle, (alpha K)i fell by similar amounts in both 2-day fasted and long-term hypocalorically fed rats, while Em depolarized significantly only in hypocalorically fed rats. In the gastrocnemius muscle, neither the 2-day fast nor the hypocaloric diet affected (alpha K)i or Em. It is suggested that the selective loss of K+ from the soleus muscle may be related to its activity pattern. 相似文献
7.
8.
Consideration must be exercised in determination of buffers and solutions used when carrying out enzyme-linked immunosorbent assays (ELISAs). A commercial monoclonal antibody kit for abscisic acid (Idetek, Inc.) gives significant false-positives with tricarboxylic acid cycle intermediates. The organic acids or contaminants interfered with ELISA assays for ABA as indicated by deviations in the slopes of standard curves of ABA in the organic acids. The interference, in the case of α-ketoglutarate, was caused by a contaminant. Of the organic buffers tested—Tris, Tricine, and Hepes—only Hepes showed false-positive ABA. In addition, we present data indicating the presence of ABA in commercial mannitol and provide a simple procedure for removal of the ABA. 相似文献
9.
Transformation of Soybean (Glycine max) by Infecting Germinating Seeds with Agrobacterium tumefaciens 总被引:9,自引:1,他引:8
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The transfer of genetic material into soybean tissue was accomplished by using an avirulent strain of Agrobacterium tumefaciens which contained the binary vector pGA482. The method used for transformation requires no tissue culture steps as it involves the inoculation of the plumule, cotyledonary node, and adjacent cotyledon tissues of germinating seeds. The identification of neomycin phosphotransferase (NPT) II enzyme activity in the tissues of 16 (R0) soybean plants indicated that the plant expressible Nos-NPT II gene, contained within the T-DNA region from pGA482, had been transferred at least into somatic tissues. Putative transformed R0 soybean plants were advanced to produce R1 plants which were also assayed for the presence of the transferred Nos-NPT II gene. The combined results of these assays indicated that about 0.7% of the surviving inoculated seeds yielded transformed tissues in the R0 plant, and that about 1/10 of these plants yielded transformed R1 plants. The presence of the Nos-NPT II gene in DNAs isolated from both R0 and R1 plant was demonstrated by using genomic blot hybridization and polymerase chain reaction methods. Integration of this gene into the soybean genome was demonstrated for three R1 soybean plants. 相似文献