No abstract

Instance segmentation of point clouds is a crucial task in 3D field with numerous applications that involve localizing and segmenting objects in a scene. However, achieving satisfactory results requires a large number of manual annotations, which is a time-consuming and expensive process. To alleviate dependency on annotations, we propose a method, called FreePoint, for underexplored unsupervised class-agnostic instance segmentation on point clouds. In detail, we represent the point features by combining coordinates, colors, normals, and self-supervised deep features. Based on the point features, we perform a multicut algorithm to segment point clouds into coarse instance masks as pseudo labels, which are used to train a point cloud instance segmentation model. To alleviate the inaccuracy of coarse masks during training, we propose a weaklysupervised training strategy and corresponding loss. Our work can also serve as an unsupervised pre-training pretext for supervised semantic instance segmentation with limited annotations. For class-agnostic instance segmentation on point clouds, FreePoint largely fills the gap with its fully-supervised counterpart based on the state-of-the-art instance segmentation model Mask3D and even surpasses some previous fully-supervised methods. When serving as a pretext task and fine-tuning on S3DIS, FreePoint outperforms training from scratch by 5.8% AP with only 10% mask annotations.

Autism spectrum disorder (ASD) cases have increased rapidly in recent decades, which is associated with various genetic abnormalities. To provide a better understanding of the genetic factors in ASD, we assessed the global scientific output of the related studies. A total of 2944 studies published between 1997 and 2018 were included by systematic retrieval from the Web of Science (WoS) database, whose scientific landscapes were drawn and the tendencies and research frontiers were explored through bibliometric methods. The United States has been acting as a leading explorer of the field worldwide in recent years. The rapid development of high-throughput technologies and bioinformatics transferred the research method from the traditional classic method to a big data-based pipeline. As a consequence, the focused research area and tendency were also changed, as the contribution of de novo mutations in ASD has been a research hotspot in the past several years and probably will remain one into the near future, which is consistent with the current opinions of the major etiology of ASD. Therefore, more attention and financial support should be paid to the deciphering of the de novo mutations in ASD. Meanwhile, the effective cooperation of multi-research centers and scientists in different fields should be advocated in the next step of scientific research undertaken.

BackgroundThyroid cancers are the most common endocrine malignancies with a dramatic increase in incidences. Anaplastic thyroid cancer is a rare but deadly form among thyroid cancers. To better understand of this field, we assessed the global scientific outputs and tried to depict its overview via bibliometric methods.MethodsApproximately 1,492 science publications published between 1997 and 2020 were included by systematic retrieval in the WoS database. The general information of them was characterized, and the developmental skeleton and research frontiers were explored.ResultsThe article number in this field has been increasing in the past 24 years. North America, East Asia, and Western Europe have reached remarkable achievements. Mutations of BARF and TERT and their downstream pathways have attracted researchers’ attention, where genetic diagnosis provides new clinical insight and several targeted therapeutic approaches have been on the clinical trial.ConclusionsNumerous efforts have been made to figure out gene expression reprogramming of anaplastic thyroid cancer and key mechanism in driving its dedifferentiation, invasion and migration process. Targeted therapy, immunotherapy, and systematic combination therapy are the recent current research hotspots. These results provide insightful clues for the funding direction and the potential breakthrough direction of the anaplastic thyroid cancer study.

Xylo-oligosaccharide (XOS) is a class of functional oligosaccharides that have been demonstrated with prebiotic activity over several decades. XOS has several advantages relative to other oligosaccharide molecules, such as promoting root development as a plant regulator, a sugar supplement for people, and prebiotics to promote intestinal motility utilization health. Now, the preparation and extraction process of XOS is gradually mature, which can maximize the extraction and avoid waste. To fully understand the recent preparation and application of XOS in different areas, we summarized the various technologies for obtaining XOS (including acid hydrolysis, enzymatic hydrolysis, hydrothermal pretreatment, and alkaline extraction) and current applications of XOS, including in animal feed, human food additives, and medicine. It is hoped that this review will serve as an entry point for those looking into the prebiotic field of research, and perhaps begin to dedicate their work toward this exciting classification of bio-based molecules.

In this article, wire beam electrode (WBE) was used to evaluate the corrosion behavior of ND steel in environmental acid atmosphere with different partial pressure of CO2. Meanwhile, corrosion products and surface morphology analysis also used to support this research. The results showed that the corrosion behavior began from the edge of droplet in dew point corrosion, and gradually spread to the center of it. The spread speed would increasing with CO2 partial pressure enhance, which was 24h in 5% CO2 and 4h in 50% CO2. Corrosion current density in the edge of droplet can form the “cathode-anode-cathode ring" structure, and disappears gradually as the corrosion time was going. Corrosion morphology observation results showed three ring shapes region and different elemental composition of different corrosion products, which is correspondence with the "cathode-anodWe-cathode ring" structure measured in WBE experiments. The results showed that the reaction gradually transferred to the uniform corrosion on electrode surface when the dew point corrosion reaction reaching the late stage. It comes from the dissolution, diffusion and reaction of gaseous corrosion medium of CO2 and O2.

BackgroundPrevious studies of the functions of IL15Rα have been limited to immune activities and skeletal muscle development. Immunological factors have been identified as one of the multiple causes of psychosis, and neurological symptoms have been described in IL15Rα knockout (KO) mice. Seeking to explore possible mechanisms for this in the IL15Rα–/– mouse brain, we analyzed gene expression patterns in the cortex and hippocampus using the RNA-seq technique.MethodsIL15Rα KO mice were generated and littermate wildtype (WT) mice were used as a control group. A Y-maze was used to assess behavior differences between the two groups. The cortex and hippocampus of 3-month-old male mice were prepared and RNA-seq and transcriptome analysis were performed by gene set enrichment analysis (GSEA).ResultsCompared with the WT group, IL15Rα KO animals showed higher speed in the novel arm and more entrance frequency in the old arm in the Y-maze experiment. GSEA indicated that 18 pathways were downregulated and 13 pathways upregulated in both cortex and hippocampus from the GO, KEGG, and Hallmark gene sets. The downregulated pathways formed three clusters: respiratory chain and electron transport, regulation of steroid process, and skeletal muscle development.ConclusionIL15Rα KO mice exhibit altered expression of multiple pathways, which could affect many functions of the brain. Lipid biosynthesis and metabolism in the central nervous system (CNS) should be investigated to provide insights into the effect of IL15Rα on psychosis in this murine model.

To explore the application prospect of GaAs/AIGaAs based Asymmetric DBS (double barriers) (ADBS) RTD (resonate tunneling diode), its transfer coefficient and RT (resonate tunneling) current density were modeled through solving of its Schrodinger equation with the method of Airy functions. Then the influences of higher barrier height on its DC characteristic and operation principles at positive and negative bias conditions were comparatively studied through simulation experiments with TCAD. The experimental results and analyses indicate that its current-voltage characteristic at negative bias is distinctively different from that at positive bias. The former appears obviously lower valley current and voltage hence lower function voltage, bigger PVCR (ratio between peak and valley currents) and broader valley bottom with similar peak current and voltage to the latter. Therefore, negative biased GaAs/AIGaAs based ADBS RTD might be more suitable for low power loss and high speed MVL (multi-valued logic) applications.The characteristic dimension (CD) of integrated semiconductor devices has been decreasing in exponential trend according to Moors law. As the CD is scaled down to nanometer, the physical limit of semiconductor devices is approached and many quantum effects appear in the traditional devices, which lead to their abnormal operations. To surmount this severe obstacle, novel devices based on quantum effects of electrons in nanostructures has been being explored and nanometer quantum devices have been being put forward little by little [1], among which RTD (Resonant Tunneling Diode) is one of the most attractive hits and became one of the nanometer devices produced in advance with the development of advanced epitaxial growing technologies such as MBE (Molecular Beam Epitaxy), MOCVD (Metal Organic Chemical Vapor Deposition)/Metal Organic Vapor-Phase Epitaxy (MOVPE) [2-6]. Its physical structure and the negative differential resistance (NDR) of RTD determine its feasibility and robustness in design of multiple-valued logic (MVL) circuits. The ultra-high-integration density characteristic of RTD is capable of greatly reducing the size of the system, the numbers of circuit interconnections and nodes. R TO is very beneficial to further improve the system performance due to its 978-1-4673-7005-9 /15/$31.00 ©2015 IEEE 380 ultra-high-speed and self-latch characteristics. The latter will lead to reduced number of devices, chip size and power consumption of a given circuit or system and all kinds of parasitic effects caused by interconnection wires can also be cut down. With the applications of MVL, more complicated logic function can be realized on a smaller chip with less pins and inter connections in between the systems, which appears remarkable merits in the high speed signal processing, transmission and storage. Therefore, combining RTD with MVL will be capable of improving the circuits' performance from many aspects, and have broad application prospects in the field of circuit design. Applied RTDs into MVL circuit d...