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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.
A temperature gradient method for lipid phase diagram construction using time-resolved x-ray diffraction. 总被引:1,自引:1,他引:0 下载免费PDF全文
A method that enables temperature-composition phase diagram construction at unprecedented rates is described and evaluated. The method involves establishing a known temperature gradient along the length of a metal rod. Samples of different compositions contained in long, thin-walled capillaries are positioned lengthwise on the rod and "equilibrated" such that the temperature gradient is communicated into the sample. The sample is then moved through a focused, monochromatic synchroton-derived x-ray beam and the image-intensified diffraction pattern from the sample is recorded on videotape continuously in live-time as a function of position and, thus, temperature. The temperature at which the diffraction pattern changes corresponds to a phase boundary, and the phase(s) existing (coexisting) on either side of the boundary can be identified on the basis of the diffraction pattern. Repeating the measurement on samples covering the entire composition range completes the phase diagram. These additional samples can be conveniently placed at different locations around the perimeter of the cylindrical rod and rotated into position for diffraction measurement. Temperature-composition phase diagrams for the fully hydrated binary mixtures, dimyristoylphosphatidylcholine (DMPC)/dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine (DPPE)/DPPC, have been constructed using the new temperature gradient method. They agree well with and extend the results obtained by other techniques. In the DPPE/DPPC system structural parameters as a function of temperature in the various phases including the subgel phase are reported. The potential limitations of this steady-state method are discussed. 相似文献
4.
H J Jaeger J MacFie C J Mitchell N Couse D Wai 《BMJ (Clinical research ed.)》1990,301(6762):1188-1191
OBJECTIVE--To assess the accuracy and safety of percutaneous biopsy of abdominal masses guided by ultrasound. DESIGN--Prospective study. SETTING--Combined gastroenterology service, Scarborough Hospital. PATIENTS--108 Consecutive patients identified as having a discrete mass on diagnostic ultrasound examination of the abdomen. INTERVENTION--A sample of tissue was obtained with an aseptic technique under local anaesthesia: an 18 steel wire gauge needle (Tru-Cut) was mounted in a spring loaded firing device (Biopty gun) that was advanced under simultaneous ultrasound scanning, permitting precise localisation of the target organ. MAIN OUTCOME MEASURE--Results of histological examination of tissue specimens. RESULTS--Biopsy failed in four patients. Adequate histological specimens were obtained in 104 patients with masses in the liver (31), pancreas (37), kidney (10), and adrenal glands (six) and in 20 undiagnosed abdominal and retroperitoneal masses. Follow up was until death or confirmation of the diagnosis. Three complications but no deaths occurred. Malignancy was suspected in 84 patients before biopsy. This was confirmed in 70 patients, in 26 of whom confirmation of dissemination obviated the need for further investigation. In 10 patients biopsy indicated a previously unsuspected primary tumour, and in 12 it showed only a benign lesion. Among 24 patients considered to have benign disease biopsy showed an unsuspected neoplasm in seven. Use of biopsy thus had a major effect on clinical management in 55 patients. Four false negative but no false positive diagnoses resulted from the procedure. CONCLUSION--Percutaneous biopsy of abdominal and retroperitoneal masses under ultrasound guidance is a safe and accurate method of obtaining a histological diagnosis. The results obtained have a considerable effect on clinical management. 相似文献
5.
Mapping parathyroid hormone, β-globin,insulin, and LDH-A genes within the human chromosome 11 short arm by spot blotting sorted chromosomes 总被引:2,自引:0,他引:2
Roger V. Lebo Mei-Chi Cheung Barry D. Bruce Vincent M. Riccardi Fa-Ten Kao Yuet Wai Kan 《Human genetics》1985,69(4):316-320
Summary Rearranged human chromosomes carrying segments of chromosome 11 were separated from the normal chromosome 11 by high-resolution chromosome sorting. Sorted chromosomes were tested with parathyroid hormone, -globin, insulin, and LDH-A gene-specific probes to determine the genes carried by each chromosome segment. Based on the gene content and karyotypes of these abnormal chromosomes, the parathyroid hormone, -globin, insulin, and LDH-A genes and the unique restriction fragment ADJ-762 are all located on the terminal band of the short arm of human chromosome 11 (band 11p15), with LDH-A proximal to the other loci. 相似文献
6.
Sandra N. Hing Carolyn M. Giles Angela H. L. Fielder J. Richard Batchelor 《Immunogenetics》1986,23(3):151-155
Twenty-three individuals from various disease groups and normal controls were identified by immunofixation with anti-C4, C4-dependent lysis, determination of Rg (Rodgers) and Ch (Chido) phenotypes, and immunoblotting with C4-specific mouse monoclonal antibody. We found that one haplotype predominates with the C4B
*
5 allele, HLA-A11, B22(55), Cw3, Bf
*
S, C4A
*
4B
*
5, which also carries the Ch
1,–2, 3 haplotype. The B5 allotype was also found with HLA-1360, HLA-1335 in Caucasoids, and HLA-B18 in non-Caucasoids; these carried the Ch
–1, –2, –3 haplotype. Our results are in accord with an earlier report of two B5 subtypes, B5Rg+ and B5Rg– (Roos et al. 1984). The specificity of the mouse monoclonal antibodies IC4 and 21312 had been previously related to C4A and C4B, respectively, but our results suggest that they relate more closely to Rg and Ch determinants. 相似文献
7.
Geok -Yong Tan Wai -Koon Tan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(2):258-264
Summary Quantitative inheritance of resistance to Phytophthora pod rot (Ppr) was studied in cocoa hybrid progeny from 12 Trinitario x Amazonian crosses and their reciprocal crosses. The crossing scheme was similar to a factorial design. Disease was assessed by the number and percentage of infected pods on each tree. Highly significant differences due to general combining abilities (GCA) were obtained for all characters, except for the GCA of Trinitario on total pod production. Differences for specific combining ability (SCA) were not significant for all characters. There were no significant differences between reciprocal crosses. The Trinitario clone K82 provided the only source for the hybrid progenies of strong Ppr resistance to the hybrid progenies, while K20 provided moderate resistance. Other parental clones — KA2-101, KA5-201, KEE 2, KEE 5, and KEE 52 — produced progenies which were susceptible to Ppr. It is evident that resistance to Ppr in cocoa is inherited additively. Maternal and cytoplasmic effects were assumed to have no influence on inheritance of resistance. It is also concluded that resistance to Ppr of the kind shown by K82 is likely to be horizontal resistance. Breeding for high-yielding cultivars combined with Ppr resistance is the most effective way of controlling Ppr of cocoa on the crops of growers with small holdings in Papua New Guinea. 相似文献
8.
Resuscitation of Vibrio cholerae O1 strain TSI-4 from a viable but nonculturable state by heat shock 总被引:3,自引:0,他引:3
Sun Nyunt Wai Tetsuhiro Moriya Katsuhiko Kondo Hiroyasu Misumi Kazunobu Amako 《FEMS microbiology letters》1996,136(2):187-191
Abstract Vibrio cholerae strain TSI-4 was incubated in an M9 salt solution at 15 °C for more than 100 days. The plate counts showed no viable cells on day 30, but a broth culture from that day showed the growth of bacteria. However, after 35 days the bacteria entered the nonculturable state, based on the assessment of both the plate counts and broth culture. A portion of the culture was heated at 45 °C for 1 min in a water bath and subsequently plated onto a nutrient agar plate. More than 1000 colonies were recovered after this heat-shock treatment. The recovered cells showed the same chromosomal DNA pattern in the restriction map and the same outer membrane protein pattern in SDS-PAGE. Recovery of viable cells by heat-shock was achieved in cultures grown on M9 salt but not from cultures grown in phosphate-buffered saline. This suggests that the presence of NH4 Cl in the M9 salt solution may support the growth of the bacteria in a low nutrient medium, while also playing an important role in resuscitation. 相似文献
9.
VNTR and microsatellite polymorphisms within the subtelomeric region of 7q. 总被引:3,自引:1,他引:2 下载免费PDF全文
The molecular basis of a highly polymorphic RFLP marker, HTY146c3 (D7S591), within the subtelomeric region of human chromosome 7q was determined by restriction-fragment and DNA sequence analysis. Two polymorphic systems were found--a simple base-substitution polymorphism and a GC-rich VNTR element with a core structure of C3AG2C2. In addition, a compound-imperfect CA dinucleotide-repeat element was identified approximately 10-20 kb from the telomeric sequence repeat (T2AG3), demonstrating that microsatellites can extend essentially to the ends of human chromosomes. The microsatellite marker, sAVH-6 (D7S594), is highly polymorphic, with 10 alleles and an observed heterozygosity of 84% found with the CEPH (Centre d'Etude du Polymorphisme Humain) reference pedigree collection. In combination with the RFLPs, the informativeness of the markers contained within 240 kb at the telomere approaches 100%. A unique genetic and physical STS marker, sAVH-6, defines the endpoint of the long arm of human chromosome 7. 相似文献
10.
Niraj Shrestha Pallavi Chaturvedi Xiaoyun Zhu Michael J. Dee Varghese George Christopher Janney Jack O. Egan Bai Liu Mark Foster Lynne Marsala Pamela Wong Celia C. Cubitt Jennifer A. Foltz Jennifer Tran Timothy Schappe Karin Hsiao Gilles M. Leclerc Lijing You Christian Echeverri Catherine Spanoudis Ana Carvalho Leah Kanakaraj Crystal Gilkes Nicole Encalada Lin Kong Meng Wang Byron Fang Zheng Wang Jin-an Jiao Gabriela J. Muniz Emily K. Jeng Nicole Valdivieso Liying Li Richard Deth Melissa M. Berrien-Elliott Todd A. Fehniger Peter R. Rhode Hing C. Wong 《Aging cell》2023,22(5):e13806