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Open-world object detection (OWOD) is a challenging problem that combines object detection with incremental learning and open-set learning. Compared to standard object detection, the OWOD setting is task to: 1) detect objects seen during training while identifying unseen classes, and 2) incrementally learn the knowledge of the identified unknown objects when the corresponding annotations is available. We propose a novel and efficient OWOD solution from a prototype perspective, which we call OCPL: Open-world object detection via discriminative Class Prototype Learning, which consists of a Proposal Embedding Aggregator (PEA), an Embedding Space Compressor (ESC) and a Cosine Similarity-based Classifier (CSC). All our proposed modules aim to learn the discriminative embeddings of known classes in the feature space to minimize the overlapping distributions of known and unknown classes, which is beneficial to differentiate known and unknown classes. Extensive experiments performed on PASCAL VOC and MS-COCO benchmark demonstrate the effectiveness of our proposed method., Comment: 4 pages, 3 figures, ICIP2022

Additional file 1: Fig S1. Characterization of antibody response induced by SARS-CoV-2 infection. Fig S2. Crossing binding and neutralizing activities of 28-26K, 25-F7 and 25-D9. Fig S3. Binding kinetics of RBD -specific mAbs with RBD from SARS-CoV-2 and SARS-CoV were measured by the Octet Red instrument. Fig S4. Common features of VH3-53/3-56 NAbs. Fig S5. Conservation of RBD residues. Fig S6. Binding kinetics of purified recombinant RBD mutants with ACE2-Fc were measured by BIAcore 8K. Fig S7. The molecular epidemiology analysis of four escape mutations F490S, N450K, R346S and F486L as of June 2021. Table S3. Antibody gene usage for selected NAbs. Table S4. hmAb panel percent binding to alanine mutants. Table S6. The alanine mutations resulted in less than 50% binding to the panel of conformation-dependent RBD-specific antibodies and ACE2 when analyzed by ELISA. Table S7. human mAb panel percent binding to natural RBD mutants. Table S8. Plasma samples from 9 individuals were screened by S-ECD and RBD binding titer and neutralizing titer against SARS-CoV-2 pseudovirus.

A new rearranged lignan, asasiebolin (1), was isolated from a kind of traditional Chinese medicine Asarum sieboldii, together with two known lignans, L-sesamin and L-asarinin. Asasiebolin (1) contained a benzo[d][1,3]dioxole-5-carboxyl moiety linked to a hydroxymethyl at C-3 of the tetrahydrofuran core, which might be rearranged after a cleavage from C-4. The structure with relative configuration was elucidated by in-depth spectral methods.

To solve the red jujube classification problem, this paper designs a convolutional neural network model with low computational cost and high classification accuracy. The architecture of the model is inspired by the multi-visual mechanism of the organism and DenseNet. To further improve our model, we add the attention mechanism of SE-Net. We also construct a dataset which contains 23,735 red jujube images captured by a jujube grading system. According to the appearance of the jujube and the characteristics of the grading system, the dataset is divided into four classes: invalid, rotten, wizened and normal. The numerical experiments show that the classification accuracy of our model reaches to 91.89%, which is comparable to DenseNet-121, InceptionV3, InceptionV4, and Inception-ResNet v2. However, our model has real-time performance.

The marine phytoplankton Prorocentrum lima is one of the toxic and harmful microalgae which can cause red tides. In chemical investigation on cultured strain P. lima PL11, seven compounds were isolated and identified by spectroscopic data, including three typical shellfish toxins okadaic acid (OA, 1), OA methyl ester (2), and prorocentrolide (3), three terpenoids (4–6), and one polyketide (7). Compounds 5 and 6 should be derived from carotenoid fucoxanthin. Compounds 4–7 were isolated from this genus of microalgae for the first time.

Diversity analysis on secondary metabolites of Antarctic microbes, Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011, together with the structural elucidation of some purified compounds, has been carried out for understanding of their chemical constituents. The methanol extracts of Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011 were subjected to HPLC-TOF MS test for diversity analysis on secondary metabolites, respectively. The chemical constituents of NJ-011 are mainly N-containing compounds including some alkaloids and short polypeptides, while those of NJ-008 are not N-containing ones. Three compounds were also isolated and identified from extract of NJ011 by different column chromatography and preparative HPLC, and their structures were elucidated as b-carboline (1), 3-benzylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (2) and 3-isobutylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (3) by comparison of TOF MS, 1Hand 13C-NMR data with those reported. More microbial material of Pseudomonas sp. NJ-011 should be needed for exploration of the minor constituents with complicated structures.

This study was aimed at evaluating the effects of Curculigoside (CCG) on the proliferation, differentiation, and calcification of mouse osteoblastic MC3T3-E1 cells. MTT assay was applied in the evaluation of MC3T3-E1 cell proliferation with CCG at different doses for different incubation periods. Alizarin red staining method was applied to observe the effect of CCG on the bone nodule formation of cells. The differentiating effects of CCG with different concentrations in cells were evaluated through the examination of alkaline phosphatase (ALP) activities by PNPP. The results showed that CCG is effective in promoting the proliferation of MC3T3-E1 cells cultured for 24 h, 48 h, and 72 h at doses ranging from 10−4 mol·L−1 to 10−8 mol·L−1. CCG at the concentration of 10−9 mol·L−1 remarkably increased the bone nodule formation of cells. The activity of ALP was stimulated by CCG at doses of 10−7 mol·L−1 and 10−9 mol·L−1 after 96 h of incubation. It was concluded that CCG has effects on stimulating the proliferation, differentiation, and calcification of MC3T3-E1 cells.

Paralytic shellfish poisoning (PSP) toxins are potent environmental neurotoxins mainly produced by marien dinoflagellates. Alexandrium spp. are the most abundant and widespread producer of saxitoxin (STX). Currently, the evolutionary history that resulted in the curious cross-kingdom distribution of STX-synthesis remained unclear. However, the increasing number of findings of toxin-producing bacteria in dinoflagellate supports the hypothesis of the bacterial origin of PSP toxins. Addtionally, evidence that there are specific symbiosis bacterial taxa associated with phytoplankton indicates the presence of specific selective mechanisms between them, and implies that the symbiosis bacteria have some vital functions to the benefit of the dinoflagellates. Culture-independent high-throughput pyrosequencing analysis is able to provide a thorough description of microbiota community in environmental samples, which also helps to reveal their potential function. This paper aims to demonstrate the biodiversity of the bacteria closely associated with two toxic dinoflagellate strains, A. tamarense and A. minutum using the pyrosequencing method.