KRADA: Known-region-aware Domain Alignment for Open World Semantic Segmentation

In semantic segmentation, we aim to train a pixel-level classifier to assign category labels to all pixels in an image, where labeled training images and unlabeled test images are from the same distribution and share the same label set. However, in an open world, the unlabeled test images probably contain unknown categories and have different distributions from the labeled images. Hence, in this paper, we consider a new, more realistic, and more challenging problem setting where the pixel-level classifier has to be trained with labeled images and unlabeled open-world images -- we name it open world semantic segmentation (OSS). In OSS, the trained classifier is expected to identify unknown-class pixels and classify known-class pixels well. To solve OSS, we first investigate which distribution that unknown-class pixels obey. Then, motivated by the goodness-of-fit test, we use statistical measurements to show how a pixel fits the distribution of an unknown class and select highly-fitted pixels to form the unknown region in each image. Eventually, we propose an end-to-end learning framework, known-region-aware domain alignment (KRADA), to distinguish unknown classes while aligning distributions of known classes in labeled and unlabeled open-world images. The effectiveness of KRADA has been verified on two synthetic tasks and one COVID-19 segmentation task

Divergence of the freshwater sleeper, Neodontobutis hainanensis (Chen, 1985) (Teleostei, Odontobutidae), in the Pearl River basin and on Hainan Island of southern China

Study of divergence of freshwater fish populations between island and adjacent mainland areas can shed light on the phylogeographical relationships of these regions. Neodontobutis hainanensis is a freshwater fish species restricted to Hainan Island and in Guangdong and Guangxi provinces in the southern mainland China. We examine the phylogenetic relationship and population structure of N. hainanensis based on 3,176 nuclear loci using a gene-capture method. STRUCTURE analysis and principal coordinate analyses (PCA) indicate that populations from Guangdong, Guangxi and Hainan are each distinct, except that some individuals of the Guangdong population share minor genetic components with individuals of the Guangxi population. In the concatenated gene tree, the Hainan population is grouped with the Guangdong population, but the coalescent tree groups the Hainan population as the sister to the Guangxi population. Finally, coalescent simulations confirmed the divergence pattern supported by the coalescent tree and revealed a one-way introgression from the Guangxi population to the Guangdong population, which can explain the discordant results supported by the concatenated and coalescent phylogenetic analyses. Due to recent decline of N. hainanensis populations and the genetic patterns in this species, as revealed in this study, the populations in the three areas should be treated as separate conservation units

Divergence of the freshwater sleeper, Neodontobutis hainanensis (Chen, 1985) (Teleostei, Odontobutidae), in the Pearl River basin and on Hainan Island of southern China

Study of divergence of freshwater fish populations between island and adjacent mainland areas can shed light on the phylogeographical relationships of these regions. Neodontobutis hainanensis is a freshwater fish species restricted to Hainan Island and in Guangdong and Guangxi provinces in the southern mainland China. We examine the phylogenetic relationship and population structure of N. hainanensis based on 3,176 nuclear loci using a gene-capture method. STRUCTURE analysis and principal coordinate analyses (PCA) indicate that populations from Guangdong, Guangxi and Hainan are each distinct, except that some individuals of the Guangdong population share minor genetic components with individuals of the Guangxi population. In the concatenated gene tree, the Hainan population is grouped with the Guangdong population, but the coalescent tree groups the Hainan population as the sister to the Guangxi population. Finally, coalescent simulations confirmed the divergence pattern supported by the coalescent tree and revealed a one-way introgression from the Guangxi population to the Guangdong population, which can explain the discordant results supported by the concatenated and coalescent phylogenetic analyses. Due to recent decline of N. hainanensis populations and the genetic patterns in this species, as revealed in this study, the populations in the three areas should be treated as separate conservation units

Neodontobutis lani, a new sleeper fish of the family Odontobutidae (Teleostei: Gobiiformes) from Guangxi, southern China

Zhou, Mingwei, He, Anyou, Wang, Fangxin, Li, Yusen, Li, Chenhong (2022): Neodontobutis lani, a new sleeper fish of the family Odontobutidae (Teleostei: Gobiiformes) from Guangxi, southern China. Zootaxa 5134 (1): 113-124, DOI: https://doi.org/10.11646/zootaxa.5134.1.

Situational Teaching Based Evaluation of College Students’ English Reading, Listening, and Speaking Ability

To effectively enhance college students’ English Reading, Listening, and Speaking (RLS) ability, it is important to explore the teaching contents, teaching methods, and the factors affecting the development of college students’ English RLS ability. The existing literature has not clearly defined college students’ English RLS ability, or selected a proper method to evaluate the ability scientifically. To solve the problems, this paper tries to evaluate college students’ English RLS ability based on situational teaching. Firstly, the authors analyzed the teaching idea of college students’ English RLS courses, and established an evaluation index system (EIS) for their RLS ability. After examining the evaluation method, the backpropagation neural network (BPNN) was optimized by genetic algorithm, and used to construct an evaluation model for college students’ English RLS ability. The feasibility of the model was demonstrated through experiments

Investigation of the Electroluminescence Mechanism of GaN-Based Blue and Green Light-Emitting Diodes with Junction Temperature Range of 120–373 K

Junction temperature (Tj) and current have important effects on light-emitting diode (LED) properties. Therefore, the electroluminescence (EL) spectra of blue and green LEDs were investigated in a Tj range of 120–373 K and in a current range of 80–240 mA based on accurate real-time measurements of Tj using an LED with a built-in sensor unit. Two maxima of the emission peak energy with changing Tj were observed for the green LED, while the blue LED showed one maximum. This was explained by the transition between the donor-bound excitons (DX) and free excitons A (FXA) in the green LED. At low temperatures, the emission peak energy, full width at half maximum (FWHM), and radiation power of the green LED increase rapidly with increasing current, while those of the blue LED increase slightly. This is because when the strong spatial potential fluctuation and low exciton mobility in the green LED is exhibited, with the current increasing, more bonded excitons are found in different potential valleys. With a shallower potential valley and higher exciton mobility, excitons are mostly bound around the potential minima. The higher threshold voltage of the LEDs at low temperatures may be due to the combined effects of the band gap, dynamic resistance, piezoelectric polarization, and electron-blocking layer (EBL)

Sensitive detection of oxidative DNA damage in cyanobacterial cells using supercoiling-sensitive quantitative PCR

Supercoiling-sensitive quantitative PCR (ss-qPCR) is a sensitive technique to detect DNA damage in cultured animal cells and cultured/clinical human cells in vitro. In this study, we investigated whether the ss-qPCR method can be applied as a sensitive means to detect oxidative DNA damage in unicellular organisms. We used the model cyanobacterium Synechococcus elongatus PCC 7942 as a test organism and H2O2 as an exogenetic oxidative toxicant. Results showed that a significant increase in the plasmid DNA damage of S. elongatus PCC 7942 was induced by H2O2 in a dose- and time-dependent manner. The sensitivity of ss-qPCR in detecting DNA damage of the cyanobacterium was higher than the cell inhibition method (up to 255 times) as calculated from the slopes of fitted curves in the tested sub-toxic concentration range of 1-5 mM H2O2. Ss-qPCR also detected repairable low-intensity DNA damage in the cyanobacterium when DNA repair inhibitors were used. The detection limit of modified ss-qPCR was one tenth of that of previous methods. We also observed that ss-qPCR can be used to detect genomic DNA conformation change of cyanobacterium exposed to H2O2. Thus, this method will provide a powerful technical support for investigating the mechanisms of cyanobacterial DNA damage by environmental factors, especially intracellular reactive oxygen species enhancement-related factors. (C) 2018 Published by Elsevier Ltd

Transcription Factor OpWRKY3 Is Involved in the Development and Biosynthesis of Camptothecin and Its Precursors in Ophiorrhiza pumila Hairy Roots

The plant Ophiorrhiza pumila produces camptothecin (CPT), a kind of terpene indole alkaloid (TIAs) that has been widely used in treatment of cancer. Tryptophan-arginine-lysine-tyrosine (WRKY) transcription factors have been reported to play important roles in plant metabolism and development. In this study, a novel WRKY transcription factor named OpWRKY3 was isolated from O. pumila, with full-length open reading frame (ORF) of 1128 bp, encoding 375 amino acids. Phylogenetic tree analysis revealed that OpWRKY3 shared the highest homology with VvWRKY30, and it is a significant feature belonging to group III. OpWRKY3 was responsive to various treatments, including gibberellin (GA3), methyl jasmonate (MJ), acetylsalicylic acid (ASA), salicylic acid (SA), and abscisic acid (ABA). Besides, OpWRKY3 is expressed predominantly in stems. Subcellular localization analysis showed that OpWRKY3 localized in the nucleus. The biomass of OpWRKY3-SRDX transgenic hairy roots (S line) was visibly suppressed, while there were slight changes between overexpression of the OpWRKY3 line (OE line) and the control. In addition, the concentration and total production of camptothecin precursors including loganin and secologanin were significantly changed in both OE and S lines while total production of CPT was significantly changed in most transgenic lines. Thus, the present work revealed that OpWRKY3 may act as a regulator in the growth and development of O. pumila, and in production of camptothecin and its precursors

Factors influencing older adults’ acceptance of voice assistants

IntroductionVoice assistants (VAs) have the potential to uphold and enhance the quality of life for older adults. However, the extent to which older adults accept and benefit from VAs may be relatively modest.MethodsThis study developed a comprehensive model combined with product and personal characteristics to explain the acceptance of VAs among older adults, using semi-structured interviews (Study 1) and questionnaires (Study 2).ResultsResults revealed that in terms of product characteristics, perceived usefulness and perceived enjoyment significantly affect behavior intention. Regarding personal characteristics of older adults, technological self-efficacy and dispositional resistance to change significantly affect behavior intention. However, no direct impact of perceived ease of use and perceived trust on behavior intention. Additionally, perceived enjoyment influenced both perceived ease of use and perceived usefulness.DiscussionResults suggested the significant role of technology self-efficacy and dispositional resistance to change in predicting the acceptance of VAs among older adults. Our newly developed model offers valuable insights for tailoring VAs to this demographic during design and implementation