20 research outputs found

    Genome sequence of the cultivated cotton <i>Gossypium arboreum</i>

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    The complex allotetraploid nature of the cotton genome (AADD; 2n = 52) makes genetic, genomic and functional analyses extremely challenging. Here we sequenced and assembled the Gossypium arboreum (AA; 2n = 26) genome, a putative contributor of the A subgenome. A total of 193.6 Gb of clean sequence covering the genome by 112.6-fold was obtained by paired-end sequencing. We further anchored and oriented 90.4% of the assembly on 13 pseudochromosomes and found that 68.5% of the genome is occupied by repetitive DNA sequences. We predicted 41,330 protein-coding genes in G. arboreum. Two whole-genome duplications were shared by G. arboreum and Gossypium raimondii before speciation. Insertions of long terminal repeats in the past 5 million years are responsible for the twofold difference in the sizes of these genomes. Comparative transcriptome studies showed the key role of the nucleotide binding site (NBS)-encoding gene family in resistance to Verticillium dahliae and the involvement of ethylene in the development of cotton fiber cells.Genetics &amp; HereditySCI(E)[email protected]; [email protected]; [email protected]

    Acoustic emission monitoring of rockbursts during TBM-excavated headrace tunneling at Jinping II hydropower station

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    AbstractTo better understand the mechanical properties of marble at Jinping II hydropower station, this paper examines the changes of brittle rocks in excavation damaged zones (EDZs) before and after excavation of tunnel with the tunnel boring machine (TBM). The paper attempts to employ the acoustic emission (AE) to study the AE characteristics and distribution of rockburst before and after TBM-excavated tunnel. It is known that the headrace tunnel #2, excavated by the drill-and-blast (D&B) method, is ahead of the headrace tunnel #3 that is excavated by TBM method. The experimental sub-tunnel #2–1, about 2000m in depth and 13m in diameter, between the two tunnels is scheduled. In the experimental sub-tunnel #2–1, a large number of experimental boreholes are arranged, and AE sensors are installed within 10m apart from the wall of the headrace tunnel #3. By tracking the microseismic signals in rocks, the location, frequency, quantity, scope and intensity of the microseismic signals are basically identified. It is observed that the AE signals mainly occur within 5m around the rock wall, basically lasting for one day before tunnel excavation and a week after excavation. Monitoring results indicate that the rockburst signals are closely related to rock stress adjustment. The rock structure has a rapid self-adjustment capacity before and after a certain period of time during tunneling. The variations of rock stresses would last for a long time before reaching a final steady state. Based on this, the site-specific support parameters for the deep tunnels can be accordingly optimized

    Multi-Scope Feature Extraction for Intracranial Aneurysm 3D Point Cloud Completion

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    3D point clouds are gradually becoming more widely used in the medical field, however, they are rarely used for 3D representation of intracranial vessels and aneurysms due to the time-consuming data reconstruction. In this paper, we simulate the incomplete intracranial vessels (including aneurysms) in the actual collection from different angles, then propose Multi-Scope Feature Extraction Network (MSENet) for Intracranial Aneurysm 3D Point Cloud Completion. MSENet adopts a multi-scope feature extraction encoder to extract the global features from the incomplete point cloud. This encoder utilizes different scopes to fuse the neighborhood information for each point fully. Then a folding-based decoder is applied to obtain the complete 3D shape. To enable the decoder to intuitively match the original geometric structure, we engage the original points coordinates input to perform residual linking. Finally, we merge and sample the complete but coarse point cloud from the decoder to obtain the final refined complete 3D point cloud shape. We conduct extensive experiments on both 3D intracranial aneurysm datasets and general 3D vision PCN datasets. The results demonstrate the effectiveness of the proposed method on three evaluation metrics compared to baseline: our model increases the F-score to 0.379 (+21.1%)/0.320 (+7.7%), reduces Chamfer Distance score to 0.998 (-33.8%)/0.974 (-6.4%), and reduces the Earth Mover's Distance to 2.750 (17.8%)/2.858 (-0.8%)

    Oral Cavity Carcinogenesis Modeled in Carcinogen-Treated Mice

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    In the present study, oral squamous cell carcinoma (OSCC) was induced in a mouse model with 20 µg/ml 4-Nitroquinoline-1-oxide (4NQO) solution in drinking water. 120 six-week-old male Balb/C mice were randomly divided into an experimental group (n=110) and a control group (n=10). They were sacrificed after 16 to 48 weeks of exposure to allow for histopathological and immuhistochemical examinations. Gross changes could be observed, including white changes, leukoplakia, erythroplakia, ulceration and papillary tumor appearance on the mucosa of the tongue dorsum of the experimental group mice during the carcinogenesis period. At the same time, no visible and histopathological changes in tongue epithelium were observed in the control group. Survivin expression was positive in dysplasia and OSCC groups but not in normal mucosa, and correlated positively with PCNA expression. Also, survivin protein staining showed statistical significance in the dysplasia group (p<0.05) but not in the OSCC group (p<0.05). Furthermore, PCNA Labelling Index (PI) in survivin positive specimens were found significantly higher than it in survivin negative specimens (p<0.01). These results showed that survivin might be closely related to cell proliferation, differentiation and carcinogenesis. It also showed that survivin might promote unrestricted multiplication and dedifferentiation of cells, making the tumor taking a malignant behavior through promoting cell mitosis, cell apoptosis, and enhancing cell proliferative activity. Therefore, the detection of expression of survivin and PCNA is helpful for early diagnosis of OSCC.status: publishe
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