RCDN -- Robust X-Corner Detection Algorithm based on Advanced CNN Model

Accurate detection and localization of X-corner on both planar and non-planar patterns is a core step in robotics and machine vision. However, previous works could not make a good balance between accuracy and robustness, which are both crucial criteria to evaluate the detectors performance. To address this problem, in this paper we present a novel detection algorithm which can maintain high sub-pixel precision on inputs under multiple interference, such as lens distortion, extreme poses and noise. The whole algorithm, adopting a coarse-to-fine strategy, contains a X-corner detection network and three post-processing techniques to distinguish the correct corner candidates, as well as a mixed sub-pixel refinement technique and an improved region growth strategy to recover the checkerboard pattern partially visible or occluded automatically. Evaluations on real and synthetic images indicate that the presented algorithm has the higher detection rate, sub-pixel accuracy and robustness than other commonly used methods. Finally, experiments of camera calibration and pose estimation verify it can also get smaller re-projection error in quantitative comparisons to the state-of-the-art.Comment: 15 pages, 8 figures and 4 tables. Unpublished further research and experiments of Checkerboard corner detection network CCDN (arXiv:2302.05097) and application exploration for robust camera calibration (https://ieeexplore.ieee.org/abstract/document/9428389

Mini-Margin Nephron Sparing Surgery for Renal Cell Carcinoma 4 cm or Less

Objectives. To explore the safety and efficacy of mini-margin nephron sparing surgery (NSS) for renal cell carcinoma (RCC) 4 cm or less. Methods. Total of 389 cases of RCC 4 cm or less with normal contralateral kidneys were included in the study, including 135 cases treated by mini-margin NSS, 98 by 1 cm-NSS and 156 by radical nephrectomy (RN). The clinical results were followed-up and comparatively analyzed. Results. The mean and median margin width for mm-NSS was 2.2 and 2.0 mm (range 0 to 5). Of them, 112 (83.0%) cases had margins of 3 mm or less, and 26 had margins of 0 mm (19.3%). The mean width of margin for 1 cm-NSS was 11.6 mm (median 12, range 10~15). None of the NSS patients had positive surgical margins. The mean follow-up for mm-NSS, 1 cm-NSS and RN patients was 69, 82 and 82 months, respectively. Three mm-NSS patients, two 1 cm- NSS and four RN patients died of non-cancer related causes. Two mm-NSS patient (1.6%) experienced local recurrence. No distant metastasis was detected in all the patients. The over all 5-year survivals for NSS and RN patients were 100%, 100% and 98.7%, respectively (P = .950). Conclusions. Mini-margin NSS is as safe and effective as 1 cm-NSS and RN in treating early localized RCC 4 cm or less

Systematic screening of long intergenic noncoding RNAs expressed during chicken embryogenesis

ABSTRACT: Long noncoding RNAs (lncRNAs) have emerged as important regulators of many biological processes, including embryogenesis and development. To provide a systematic analysis of lncRNAs expressed during chicken embryogenesis, we used Iso-Seq and RNA-Seq to identify potential lncRNAs at embryonic stages from d 1 to d 8 of incubation: sequential stages covering gastrulation, somitogenesis, and organogenesis. The data characterized an expanded landscape of lncRNAs, yielding 45,410 distinct lncRNAs (31,282 genes). Amongst these, a set of 13,141 filtered intergenic lncRNAs (lincRNAs) transcribed from 9803 lincRNA gene loci, of which, 66.5% were novel, were further analyzed. These lincRNAs were found to share many characteristics with mammalian lincRNAs, including relatively short lengths, fewer exons, lower expression levels, and stage-specific expression patterns. Functional studies motivated by “guilt-by-association” associated individual lincRNAs with specific GO functions, providing an important resource for future studies of lincRNA function. Most importantly, a weighted gene co-expression network analysis suggested that genes of the brown module were specifically associated with the day 2 stage. LincRNAs within this module were co-expressed with proteins involved in hematopoiesis and lipid metabolism. This study presents the systematic identification of lincRNAs in developing chicken embryos and will serve as a powerful resource for the study of lincRNA functions

Mining Negative Temporal Contexts For False Positive Suppression In Real-Time Ultrasound Lesion Detection

During ultrasonic scanning processes, real-time lesion detection can assist radiologists in accurate cancer diagnosis. However, this essential task remains challenging and underexplored. General-purpose real-time object detection models can mistakenly report obvious false positives (FPs) when applied to ultrasound videos, potentially misleading junior radiologists. One key issue is their failure to utilize negative symptoms in previous frames, denoted as negative temporal contexts (NTC). To address this issue, we propose to extract contexts from previous frames, including NTC, with the guidance of inverse optical flow. By aggregating extracted contexts, we endow the model with the ability to suppress FPs by leveraging NTC. We call the resulting model UltraDet. The proposed UltraDet demonstrates significant improvement over previous state-of-the-arts and achieves real-time inference speed. To facilitate future research, we will release the code, checkpoints, and high-quality labels of the CVA-BUS dataset used in our experiments.Comment: 10 pages, 4 figures, MICCAI 2023 Early Accep

Rice lipid transfer protein, OsLTPL23, controls seed germination by regulating starch-sugar conversion and ABA homeostasis

Seed germination is vital for ensuring the continuity of life in spermatophyte. High-quality seed germination usually represents good seedling establishment and plant production. Here, we identified OsLTPL23, a putative rice non-specific lipid transport protein, as an important regulator responsible for seed germination. Subcellular localization analysis confirmed that OsLTPL23 is present in the plasma membrane and nucleus. The knockout mutants of OsLTPL23 were generated by CRISPR/Cas9-mediated genome editing, and osltpl23 lines significantly germinated slower and lower than the Nipponbare (NIP). Starch and soluble sugar contents measurement showed that OsLTPL23 may have alpha-amylase inhibitor activity, and high soluble sugar content may be a causal agent for the delayed seed germination of osltpl23 mutants. Transcript profiles in the germinating seeds exhibited that the abscisic acid (ABA)-responsive genes, OsABI3 and OsABI5, and biosynthesis genes, OsNCED1, OsNCED2, OsNCED3 and OsNCED4, are obviously upregulated in the osltpl23 mutants compared to NIP plants, conversely, ABA metabolism genes OsABA8ox1, OsABA8ox2 and OsABA8ox3 are stepwise decreased. Further investigations found that osltpl23 mutants displays weakened early seedling growth, with elevated gene expresssion of ABA catabolism genes and repressive transcription response of defence-related genes OsWRKY45, OsEiN3, OsPR1a, OsPR1b and OsNPR1. Integrated analysis indicated that OsLTPL23 may exert an favorable effect on rice seed germination and early seedling growth via modulating endogenous ABA homeostasis. Collectively, our study provides important insights into the roles of OsLTPL23-mediated carbohydrate conversion and endogenous ABA pathway on seed germination and early seedling growth, which contributes to high-vigor seed production in rice breeding

“Diminishing returns” and leaf area-biomass scaling of ferns in subtropical ecosystems

Foliage leaves are the primary photosynthetic organ of the majority of vascular plants, and their area vs. biomass scaling relationships provide valuable insights into the capacity and investment in light interception, which is critical to plant growth and performance. The “diminishing returns” hypothesis (DRH), which is based primarily on data from gymnosperms and angiosperms, posits that leaf (lamina) area scales with leaf dry mass. on average with a scaling exponent less than 1.0. However, it remains uncertain whether DRH applies to ferns or whether ecological factors affect the scaling exponents governing fern leaf morphometrics. To address this issue, 182 individuals of 28 subtropical ferns species were studied at low, medium, and high elevations (i.e., 600 m, 900 m, and 1200 m, respectively) in Mount Wuyi National Park, Jiangxi Province, China. The scaling relationships between leaf area and leaf biomass for individual and total leaf of ferns at different elevations were examined by using standardized major axis regression protocols. Analyses of the 28 fern species (using Blomberg K-value protocols) indicated no phylogenetic biases among the species compositions of the three different elevations. In addition, at the individual plant level, individual leaf area (ILA) did not differ significantly among the three different elevations (P > 0.05). However, individual leaf mass (ILM) was significantly higher at 900m than at 1200m (P < 0.05), resulting in a significantly higher leaf mass per area (LMA) at the 900m elevation than at the 600m and 1200m elevations (P < 0.05). The ILA and ILM at the 900m elevation were significantly higher than at the 600m elevation (P < 0.05). At the species level, ILA and ILM did not differ significantly among the three elevations (P > 0.05). The total leaf area per individual (TLA) did not differ significantly across the different elevations (P > 0.05). However, total leaf mass per individual (TLM) did differ significantly (P < 0.05). At the individual plant level, the scaling exponents for ILA vs. ILM and TLA vs. TLM at the three different elevations were all significantly less than 1.0 (P < 0.05), which was consistent with the DRH. At the species level, the scaling exponents for the ILA vs. ILM were significantly less than 1.0 at the middle and high elevations, but not at the low elevation. The scaling exponents of the TLA and TLM were numerically highest in the middle elevation, and all were less than 1.0 for the three elevations. These results indicate that the scaling relationships of leaf area versus mass of subtropical ferns at different elevations support the DRH hypothesis. The study further informs our understanding of the resource allocation strategies of an ancient and diverse plant lineage

Experimental study on mechanical and acoustic emission characteristics of sedimentary sandstone under different loading rates

In the field of rock engineering, complexity of stress environment is an important factor affecting its stability. Thus, in view of fracture mechanism of rock under different loading rates within the scope of quasi-static strain rate, four groups of uniaxial compression tests with different strain rates were carried out on sandstone specimens, and strength, deformation, failure modes and acoustic emission characteristics of specimens were compared and analyzed. Furthermore, the fracture mechanism was discussed from the perspective of fracture characteristics based on fractal dimension, crack propagation law inverted through acoustic emission b-value, and micro fracture morphology. The results showed that as the strain rate increased from 10 to 5 s−1 to 10−2 s−1, the fractal dimension of rock fragments increased, and the fractal dimension of rock fragments increased by 9.66%, 7.32%, and 3.77% successively for every 10 times increase in strain rate, which means that the equivalent size of fragments was getting smaller, and the fragmentation feature was becoming increasingly prominent. The crack propagation process based on acoustic emission b-value showed that with the increase of loading rate, the specimen entered the rapid crack propagation stage earlier, in order of 68%, 66%, 29%, and 22% of peak stress. Moreover, the microscopic fracture morphology showed that with the increase of loading rate, transgranular phenomenon was clear, and the fracture morphology changed from smooth to rough. That meant that the fracture of sandstone rock at high loading rates was mainly caused by the propagation of large cracks, which was different from the slow process of initiation, convergence and re-propagation of small cracks at low strain rates

Characterization of Coal Porosity for Naturally Tectonically Stressed Coals in Huaibei Coal Field, China

The enrichment of coalbed methane (CBM) and the outburst of gas in a coal mine are closely related to the nanopore structure of coal. The evolutionary characteristics of 12 coal nanopore structures under different natural deformational mechanisms (brittle and ductile deformation) are studied using a scanning electron microscope (SEM) and low-temperature nitrogen adsorption. The results indicate that there are mainly submicropores (2~5 nm) and supermicropores (<2 nm) in ductile deformed coal and mesopores (10~100 nm) and micropores (5~10 nm) in brittle deformed coal. The cumulative pore volume (V) and surface area (S) in brittle deformed coal are smaller than those in ductile deformed coal which indicates more adsorption space for gas. The coal with the smaller pores exhibits a large surface area, and coal with the larger pores exhibits a large volume for a given pore volume. We also found that the relationship between S and V turns from a positive correlation to a negative correlation when S>4 m2/g, with pore sizes <5 nm in ductile deformed coal. The nanopore structure (<100 nm) and its distribution could be affected by macromolecular structure in two ways. Interconversion will occur among the different size nanopores especially in ductile deformed coal

A new survival model based on ferroptosis-related genes for prognostic prediction in clear cell renal cell carcinoma

In this study, we analyzed the clinical significance of ferroptosis-related genes (FRGs) in 32 cancer types in the GSCA database. We detected a 2-82% mutation rate among 36 FRGs. In clear cell renal cell carcinoma (ccRCC; n=539) tissues from the The Cancer Genome Atlas database, 30 of 36 FRGs were differentially expressed (up- or down-regulated) compared to normal kidney tissues (n=72). Consensus clustering analysis identified two clusters of FRGs based on similar co-expression in ccRCC tissues. We then used LASSO regression analysis to build a new survival model based on five risk-related FRGs (CARS, NCOA4, FANCD2, HMGCR, and SLC7A11). Receiver operating characteristic curve analysis confirmed good prognostic performance of the new survival model with an area under the curve of 0.73. High FANCD2, CARS, and SLC7A11 expression and low HMGCR and NCOA4 expression were associated with high-risk ccRCC patients. Multivariate analysis showed that risk score, age, stage, and grade were independent risk factors associated with prognosis in ccRCC. These findings demonstrate that this five risk-related FRG-based survival model accurately predicts prognosis in ccRCC patients, and suggest FRGs are potential prognostic biomarkers and therapeutic targets in several cancer types