235 research outputs found
Small, Versatile and Mighty: A Range-View Perception Framework
Despite its compactness and information integrity, the range view
representation of LiDAR data rarely occurs as the first choice for 3D
perception tasks. In this work, we further push the envelop of the range-view
representation with a novel multi-task framework, achieving unprecedented 3D
detection performances. Our proposed Small, Versatile, and Mighty (SVM) network
utilizes a pure convolutional architecture to fully unleash the efficiency and
multi-tasking potentials of the range view representation. To boost detection
performances, we first propose a range-view specific Perspective Centric Label
Assignment (PCLA) strategy, and a novel View Adaptive Regression (VAR) module
to further refine hard-to-predict box properties. In addition, our framework
seamlessly integrates semantic segmentation and panoptic segmentation tasks for
the LiDAR point cloud, without extra modules. Among range-view-based methods,
our model achieves new state-of-the-art detection performances on the Waymo
Open Dataset. Especially, over 10 mAP improvement over convolutional
counterparts can be obtained on the vehicle class. Our presented results for
other tasks further reveal the multi-task capabilities of the proposed small
but mighty framework
Curricular Object Manipulation in LiDAR-based Object Detection
This paper explores the potential of curriculum learning in LiDAR-based 3D
object detection by proposing a curricular object manipulation (COM) framework.
The framework embeds the curricular training strategy into both the loss design
and the augmentation process. For the loss design, we propose the COMLoss to
dynamically predict object-level difficulties and emphasize objects of
different difficulties based on training stages. On top of the widely-used
augmentation technique called GT-Aug in LiDAR detection tasks, we propose a
novel COMAug strategy which first clusters objects in ground-truth database
based on well-designed heuristics. Group-level difficulties rather than
individual ones are then predicted and updated during training for stable
results. Model performance and generalization capabilities can be improved by
sampling and augmenting progressively more difficult objects into the training
samples. Extensive experiments and ablation studies reveal the superior and
generality of the proposed framework. The code is available at
https://github.com/ZZY816/COM.Comment: Accepted by CVPR 2023. The code is available at
https://github.com/ZZY816/CO
Stator vibration of generator under SAERISC faults
This paper analyzes the stator vibration response under static air-gap eccentricity and rotor inter-turn short circuit composite faults (SAERISC). The detailed formula of the magnetic force on stator is firstly deduced. Then the finite element simulations and practical experiments are taken to investigate the stator vibration response. It’s shown that, 1st to 4th stator vibrations will be produced. The development of the short circuit will decrease the 2nd vibration but increase the 4th vibration, while the increment of the eccentricity will increase the 1st to 4th vibrations at the same time
Experimental observation of conditional past-future correlations
Conditional past-future correlations measure the lack of statistical independence between past and future system measurement outcomes when conditioned to a given state at a present time. Quantum non-Markovian memory effects are present whenever this correlation is not null. Conditional past-future correlations can also be used to detect initial system-environment correlated states. In this work, we provide theoretical and experimental evidence for these general properties. We build an optical setup that implements the dynamics of a qubit interacting with a dephasing spin bath. Both finite and infinite bath-size limits are observed. Confirmation of theoretical predictions for conditional past-future correlations is obtained. This work provides experimental support for quantum memory indicators based solely on outcomes of explicit system measurement processes.Fil: Yu, Shang. University of Science and Technology of China; ChinaFil: Budini, Adrian Adolfo. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro | Universidad Nacional de Cuyo. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnol.conicet - Patagonia Norte. Unidad de Adm.territorial; Argentina. Universidad Tecnológica Nacional; ArgentinaFil: Wang, Yi Tao. University of Science and Technology of China; ChinaFil: Ke, Zhi Jin. University of Science and Technology of China; ChinaFil: Meng, Yu. University of Science and Technology of China; ChinaFil: Liu, Wei. University of Science and Technology of China; ChinaFil: Li, Zhi Peng. University of Science and Technology of China; ChinaFil: Li, Qiang. University of Science and Technology of China; ChinaFil: Liu, Zheng Hao. University of Science and Technology of China; ChinaFil: Xu, Jin Shi. University of Science and Technology of China; ChinaFil: Tang, Jian Shun. University of Science and Technology of China; ChinaFil: Li, Chuan-Feng. University of Science and Technology of China; ChinaFil: Guo, Guang Can. University of Science and Technology of China; Chin
Spatial and temporal clonal evolution of intrahepatic cholangiocarcinoma
Background & Aims:
Intrahepatic cholangiocarcinoma (ICC) is the second-most lethal primary liver cancer. Little is known about intratumoral heterogeneity (ITH) and its impact on ICC progression. We aim to investigate its ITH in hope of helping develop new therapeutic strategies.
Methods:
We obtained 69 spatially distinct regions from 6 operable ICCs. Patient-derived primary cancer cells (PDPCs) were established for each region, followed by whole-exome sequencing(WES) and multi-level validation.
Results:
We observed widespread ITH for both somatic mutations and clonal architecture, shaped by multiple mechanisms, like clonal “illusion”, parallel evolution and chromosome instability. A median of 60.3% mutations were heterogeneous mutations, among which 85% of the driver mutations located on the branches of tumor phylogenetic trees. Many truncal and clonal driver mutations occurred in tumor-suppressor genes, such as TP53, SMARCB1 and PBRM1 that involved in DNA repair and chromatin-remodeling. Genome doubling occurred in most cases (5/6) after the accumulation of truncal mutations and was shared by all intratumoral subregions. In all cases, ongoing chromosomal instability is evident throughout the evolutionary trajectory of ICC. The recurrence of ICC1239 provided evidence to support the polyclonal metastatic seeding in ICC. The change of mutation landscape and internal diversity among subclones during metastasis, such as the loss of chemoresistance mediator, may be used for new treatment strategy. Targeted therapy against truncal alterations, such as IDH1, JAK1, and KRAS mutations and EGFR amplification, could be developed in 5/6 patients.
Conclusions:
Integrated investigations of spatial ITH and clonal evolution may provide an important molecular foundation for enhanced understanding of tumorigenesis and progression in ICC.
Lay summary:
We applied multiregional whole exome sequencing to investigate the evolution trajectory of ICC. The results revealed that many fuels, such as parallel evolution and chromosome instability, may participate and promote the branch diversity of ICC. Interestingly, in one patient with primary and recurrent metastatic tumors, we found some clues of polyclonal metastatic seeding, indicating that symbiotic communities of multiple clones existed and were maintained during metastasis. More realistically, some truncal alterations, such as IDH1, JAK1, and KRAS mutations and EGFR amplification, can be promising treatment targets for ICC patients
Superconductivity and Charge-density-wave-like Transition in Th2Cu4As5
We report the synthesis, crystal structure, and physical properties of a
novel ternary compound, ThCuAs. The material crystallizes in a
tetragonal structure with lattice parameters {\AA} and
{\AA}. Its structure can be described as an alternating stacking
of fluorite-type ThAs layers with antifluorite-type double-layered
CuAs slabs. The measurement of electrical resistivity, magnetic
susceptibility and specific heat reveals that ThCuAs undergoes bulk
superconducting transition at 4.2 K. Moreover, all these physical quantities
exhibit anomalies at 48 K, where the Hall coefficient change the sign. These
findings suggest a charge-density-wave-like (CDW) transition, making
ThCuAs a rare example for studying the interplay between CDW and
superconductivity.Comment: 11 pages, 6 figures, and 1 tabl
Laser Direct Writing of Visible Spin Defects in Hexagonal Boron Nitride for Applications in Spin-Based Technologies
Optically addressable spins in two-dimensional hexagonal boron nitride (hBN)
attract widespread attention for their potential advantage in on-chip quantum
devices, such as quantum sensors and quantum network. A variety of spin defects
have been found in hBN, but no convenient and deterministic generation methods
have been reported for other defects except negatively charged boron vacancy
(). Here we report that by using femtosecond laser direct writing
technology, we can deterministically create spin defect ensembles with spectra
range from 550 nm to 800 nm on nanoscale hBN flakes. Positive single-peak
optically detected magnetic resonance (ODMR) signals are detected in the
presence of magnetic field perpendicular to the substrate, and the contrast can
reach 0.8%. With the appropriate thickness of hBN flakes, substrate and
femtosecond laser pulse energy, we can deterministically and efficiently
generate bright spin defect array. Our results provide a convenient
deterministic method to create spin defects in hBN, which will motivate more
endeavors for future researches and applications of spin-based technologies
such as quantum magnetometer array
MicroRNA-138 Aggravates Inflammatory Responses of Macrophages by Targeting SIRT1 and Regulating the NF-κB and AKT Pathways
Background/Aims: With increased understanding of sepsis, mortality is decreasing. However, there is still a lack of effective therapeutic strategy. The inflammatory response of macrophages is critical during sepsis. Methods: Macrophages were stimulated with LPS. Western blotting and qRT-PCR were used to detect inflammatory responses. Then, the inhibitor of microRNA-138 was transfected and Western blotting, qRT-PCR, H&E staining and ELISA were used to verify the role of microRNA-138 in inflammation. Then target gene prediction databases were used to predict the potential target of microRNA-138. Both animal and cell models under LPS challenges were established to verify the regulation of SIRT1 and microRNA-138 during inflammation. Results: The present study showed that microRNA-138 was increased in macrophages stimulated with LPS. Additionally, the NF-κB and AKT pathways were both activated. The pre-treatment of microRNA-138 inhibitor decreased inflammatory factors, downregulated the NF-κB pathway, activated the AKT pathway and protected against organ damage in mice challenged with LPS. SIRT1 was demonstrated as a potential target of microRNA-138In macrophages stimulated with LPS, the inhibition effect of microRNA-138 inhibitor on inflammation was lost by SIRT1 siRNA pre-treatment. In the animal model, the protective effect of microRNA-138 antagomir disappeared in SIRT1 knockout mice. Conclusion: We demonstrated that miR-138 participated in the inflammatory process by inhibiting SIRT1 and activating the NF-κB pathway
Prevalence and Molecular Characterization of Cyclospora cayetanensis, Henan, China
To determine prevalence of Cyclospora cayetanensis infection in Henan, China, we conducted a study of 11,554 hospital patients. Prevalence was 0.70% (95% confidence interval 0.70% ± 0.15%), with all age groups infected. Most cases were found in the summer. Minor sequence polymorphisms were observed in the 18S rRNA gene of 35 isolates characterized
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