A study on giant panda recognition based on images of a large proportion of captive pandas

1. 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.
2. 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.
3. The algorithm achieved 96.27% accuracy in panda recognition and 100% accuracy in detection.
4. 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.

     

Analysis of the structure and expression of the c-myc oncogene in cervical tumor and in cervical tumor-derived cell lines

The structure of the c-myc oncogene in 17 cervical tumors and patient-matched nontumor tissues from Chinese patients residing in Taiwan was analysed. In contrast to recent reports on Mexican patients, none of the samples showed rearrangements and sequence amplification in the c-myc gene. The discrepancy may be explained by different carcinogenesis mechanisms being in operation in different geographic regions. Although no structural alterations in the c-myc gene were found in seven cervical carcinoma cell lines analysed, Northern blot analysis indicated different levels of c-myc gene expression which may be related to the presence of human papillomavirus (HPV) sequence in the cell and suggests a possible c-myc-hpv interaction in some stages of the transformation process.     

Recruitment of Nox4 to a Plasma Membrane Scaffold Is Required for Localized Reactive Oxygen Species Generation and Sustained Src Activation in Response to Insulin-like Growth Factor-I

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.     

Cleavage of territrems by alkaline hydrogen peroxide: Isolation and characterization of the aromatic moiety of territrems

The chemical reaction of cleavaging territrem B to give 3,4,5-trimethoxy benzoic acid by alkaline hydrogen peroxide was investigated. The method was applied for confirmation of the chemical structure of the aromatic moiety of territrem A, A’, B, and B’. The physicochemical properties of the aromatic cleavage product of territrem Aindicated the structure as 3,4-methylendioxy, 5-methoxy benzoic acid (or 4-methoxy, 6-carboxy, 1, 3-benzodioxole). The experiment also gave the evidences that territrem A and A’, on the other hand territrem B and B’ have the identical aromatic moieties on their structures.     

Calorimetric studies of the effects of cholesterol on the phase transition of C(18):C(10) phosphatidylcholine.

Differential scanning calorimetry (DSC) has been employed to study the effects of cholesterol on the phase transition of C(18):C(10) phosphatidylcholine (C(18):C(10)PC). C(18):C(10)PC is an asymmetric mixed-chain phosphatidylcholine known to form mixed-interdigitated structures below the transition temperature and form partially interdigitated lipid bilayers above the transition. Three types of samples were used. The treated sample is the lipid dispersion that had undergone three freeze-thaw cycles and stored at 4 degrees C for more than 48 h. The untreated sample was made by vortexing the dry lipid in 50 mM KCl, without the above-mentioned pretreatment. The cold-treated sample was prepared by incubating the treated sample at -20 degrees C for 15 d. There is no apparent difference in the DSC curves between the treated and cold-treated samples. The data derived from the treated samples seem to be more reproducible. The DSC curves between the cholesterol/C(18):C(10)PC and cholesterol/symmetric diacylphosphatidylcholine mixtures are different in three aspects: overall appearance, the cholesterol dependence of delta H, and the effect of cholesterol on the maximal transition temperature Tm, the onset temperature To, and the completion temperature Tc. for both the treated and untreated samples, the total enthalpy change delta H of the phase transition of C(18):C(10)PC decreases with increasing cholesterol content, approaching zero at approximately 25 mol%. This level is lower than the total enthalpy changes reported previously for the cholesterol/symmetric diacylphosphatidylcholine mixtures. Both the heating and cooling thermograms show that Tm, To, and Tc decrease with increasing cholesterol content. The decreasing rates of these temperatures with cholesterol are in the neighborhood of -0.24 degree per mol% of cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS)     

Determination of the enantiomeric composition of (R*,S*)-1-ethylpropyl 2-methyl-3-hydroxypentanoate, the male-produced aggregation pheromone of Sitophilus granarius

The enantiomeric composition of sitophilate, the granary weevil [Sitophilus granarius (L.)] male-produced aggregation pheromone [(R^*,S^*)-1-ethylpropyl 2-methyl-3-hydroxypentanoate)], was determined by three methods: (1) bioassaying the synthetic (2S,3R) and (2R,3S) enantiomers of the active (R^*,S^*) diastereomer; (2) ¹H NMR spectroscopy of Mosher ester derivatives of the natural pheromone and synthetic (2S,3R)-and (2R,3S)-sitophilate; and (3) capillary GLC comparisons of the retention times of derivatized natural pheromone and the two synthetic enantiomers. The combined methods confirmed the (2S,3R) enantiomer as the active form of sitophilate. Male granary weevils were shown to produce >96% (2S,3R)-sitophilate. No significant attraction of S. granarius by the (2R,3S) enantiomer was observed. Rice and maize weevils [S. oryzae (L.) and S. zeamais Motschulsky] were not attracted by (2S,3R)-sitophilate. S. granarius L. est un déprédateur important des grains stockés. Le (R^*,S^*)-1-éthylpropyl 2-méthyl-3-hydroxypentanoate a été identifié en 1987 comme le principal composé du sitophilate, la phéromone mâle d'agrégation de S. granarius. La composition énantiométrique du sitophilate a été déterminée par 3 méthodes:

The primary structure of human apolipoprotein A-IV

Human apolipoprotein (apo) A-IV was purified from chylous ascites fluid. Proteolytic peptides produced by trypsin and Staphylococcus aureus V8 proteinase digestions were purified by high-performance liquid chromatography and sequenced. Human apoA-IV contains 376 amino acid residues. The peptide-derived sequence generally matches two previously reported DNA-derived amino acid sequences except for discrepancies in five positions. In order to examine these discrepancies further, one complete apoA-IV cDNA clone and another partial clone were sequenced. Comparison of all the available information indicates that the peptide-derived sequence reported here is accurate. Sequencing errors probably account for some of the discrepancies between the two primary sequences predicted by earlier nucleotide analyses. In certain positions, however, bona fide sequence heterogeneity or cloning artifact cannot be excluded.     

Diagnosis of abdominal masses with percutaneous biopsy guided by ultrasound.

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.