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It is reported that teachers' satisfaction levels are lower and stress levels are higher than other professional groups in many countries. This is especially true for science, technology, engineering, and mathematics (STEM) teachers. Considering job satisfaction has a direct impact on turnover intention, low satisfaction levels have led to high turnover rates and thus exacerbated the shortages of STEM teachers. Hence, there is an urgent need to explore the antecedents of novice STEM teachers' job satisfaction. This study proposes a new model to show how novice STEM teachers' personality traits and perceived social support influence their job satisfaction. A total of 2592 novice STEM teachers in eighteen randomly selected high schools in China were recruited. Data were analyzed using the structural equation modeling approach. The results illustrated that most novice STEM teachers had low levels of job satisfaction. Novice STEM teachers' personality traits could directly and indirectly impact their job satisfaction. Meanwhile, novice STEM teachers' job satisfaction was also directly influenced by work engagement and indirectly influenced by their perceived social support. Our findings theoretically contribute to the understanding of the determinants of STEM teachers' job satisfaction and have important practical implications. [ABSTRACT FROM AUTHOR]

The artificial propagation of the endangered Solenaia oleivora, with unknown fish hosts, was performed via in vitro culture with bighead carp, grass carp, common carp, bovine, and rabbit sera. The effects of glochidium density on transformation rates were evaluated, and the development of juveniles that metamorphosed successfully was documented. The control group had a transformation rate of 0 and a contamination rate of 0. No significant differences were found in the transformation and contamination rates of the bighead carp, grass carp, and common carp serum groups, and their transformation rates were significantly higher, and contamination rates were significantly lower than those of the bovine and rabbit serum groups. Moreover, no significant differences were observed in the transformation rates of glochidia (culture density, 2000–5000 glochidia/dish) in contamination-free conditions. Specimen shell length/height increased from 1.08 ± 0.01 on the first day to 3.08 ± 0.29 during the 13th week. On the basis of anterior and posterior growth differences, juvenile growth was divided into the following three phases: the rapid anterior growth period, distinct anterior and posterior idiophase, and rapid posterior growth period. This study not only provides technological support for the artificial propagation of S. oleivora but also lays a foundation for resource recovery. [ABSTRACT FROM AUTHOR]

Cipangopaludina cathayensis (Gastropoda: Prosobranchia; Mesogastropoda; Viviparidae) is widely distributed in the freshwater habitats of China. It is an economically important snail with high edible and medicinal value. However, the genomic resources and the reference genome of this snail are lacking. In this study, we assembled the first chromosome-level genome of C. cathayensis. The preliminary assembly genome was 1.48 Gb in size, with a contig N50 size of 93.49 Mb. The assembled sequences were anchored to nine pseudochromosomes using Hi-C data. The final genome after Hi-C correction was 1.48 Gb, with a contig N50 of 98.49 Mb and scaffold N50 of 195.21 Mb. The anchored rate of the chromosome was 99.99%. A total of 22,702 protein-coding genes were predicted. Phylogenetic analyses indicated that C. cathayensis diverged with Bellamya purificata approximately 158.10 million years ago. There were 268 expanded and 505 contracted gene families in C. cathayensis when compared with its most recent common ancestor. Five putative genes under positive selection in C. cathayensis were identified (false discovery rate <0.05). These genome data provide a valuable resource for evolutionary studies of the family Viviparidae, and for the genetic improvement of C. cathayensis. [ABSTRACT FROM AUTHOR]

Centrally staged combustion technique is often used in the military high-temperature-rise combustor. The pilot-stage structure affects the flow characteristics in the centrally staged combustor, which further affects the performance of ignition, combustion, and emission of military aero-engines. In order to increase the flow capacity of the swirler, the swirler with a non-rotating channel structure was designed. In this work, the influences of the pilot-stage structure on the flow characteristics in the centrally staged high-temperature-rise combustor are investigated. The flow fields of combustors with different pilot-stage swirl numbers (0.44, 0.60, and 0.71) are analyzed by large eddy simulation (LES). The results demonstrate that the primary recirculation zone (PRZ) becomes gradually longer and wider as the pilot-stage swirl number increases. In the combustors with three different pilot-stage structures, the precessing vortex core (PVC) was formed near the shear layer at the outlet of the pilot stage. The PVC frequency decreased from 1670 Hz to 1425 Hz and 1400 Hz with the increase of the pilot-stage swirl number from 0.44 to 0.60 and 0.71, respectively, and the breakdown position of the PVC shifted forward. The proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) methods are used to analyze the dynamic flow fields. It was observed that the corresponding frequency of the main pulsation structure decreased, and the flow instability was aggravated with the increase of the pilot-stage swirl number. The results deepen the understanding of the influences of the pilot-stage structure on the flow characteristics in the centrally staged high-temperature-rise combustor. [ABSTRACT FROM AUTHOR]

MAPKAPK2 (MK2) is an important regulator of the p38 mitogen-activated protein kinase (p38 MAPK) pathway, which is involved in a plethora of cellular processes concluding the development of gamete cells in meiosis and resisting pathogenic bacterial infestation. Hyriopsis cumingii is a significant mussel resource in China and a good material for pearl breeding. To explore the role of MK2 in H. cumingii, MK2 was identified and cloned, whose full-length cDNA was 1568 bp, including 87 bp in 5′ UTR, 398 bp in 3′ UTR, and 1083 bp in the open reading frame (ORF) region, encoding 360 amino acids. The expression of MK2 was the highest in the gills. Meanwhile, there was a significant difference in the gonads. After Aeromonas hydrophila and Lipopolysaccharide (LPS) infestation, the transcript level of the MK2 was upregulated in the gills. It indicated that MK2 might be involved in the innate immune response of H. cumingii after a pathogenic attack. After quantifying H. cumingii of different ages, it was found that the expression of MK2 was highest at 1 year old. In situ hybridization (ISH) results showed that the blue-purple hybridization signal was very significant in the oocytes and egg membranes of the female gonads of H. cumingii. The expression of MK2 increased gradually at the age of 1 to 5 months and showed a downward trend at the age of 5 to 8 months. It was suggested that MK2 might play an important role in the formation of primitive germ cells in H. cumingii. To sum up, MK2 might not only be involved in the immune response against pathogenic bacterial infection but also might play an important role in the development of the gonads in H. cumingii. [ABSTRACT FROM AUTHOR]

Ovarian cancer is regarded as one of the most severe malignancies for women in the world. Death rates have remained steady over the past five decades, due to the undeniable inefficiency of the current treatment in preventing its recurrence and death. The development of new effective alternative agents for ovarian cancer treatment is becoming increasingly critical. Tea saponins (TS) are triterpenoidsaponins composed of sapogenins, glycosides, and organic acids, which possess a variety of pharmacological activities, and have shown promise in the anti-cancer field. Through cell CellTiter 96® Aqueous One Solution Cell Proliferation assay (MTS) assay, colony formation, Hoechst 33342 staining assay, caspase-3/7 activities, flow cytometry for apoptosis analysis, andWestern blot, we observed that TS isolated from the seeds of tea plants, Camellia sinensis, exhibited strong anti-proliferation inhibitory effects on OVCAR-3 and A2780/CP70 ovarian cancer cell lines. Our results indicate that TS may selectivity inhibit human ovarian cancer cells by mediating apoptosis through the extrinsic pathway, and initiating anti-angiogenesis via decreased VEGF protein levels in a HIF-1α-dependent pathway. Our data suggests that, in the future, TS could be incorporated into a potential therapeutic agent against human ovarian cancer. [ABSTRACT FROM AUTHOR]

Numerous studies have sought to clarify the link between biological communities and environmental factors in freshwater, but an appropriate model is still needed to predict the effect of water quality and hydromorphology improvement on biological communities and to provide useful information for ecological restoration planning. In this study, a support vector machine (SVM) was used to predict the bio-indicators of an aquatic ecosystem (i.e., macroinvertebrates, fish, algae communities) in the Taizi River, northeast China. Environmental factors, including physico-chemical (i.e., dissolved oxygen (DO), electricity conductivity (EC), ammonia nitrogen (NH3-N), chemical oxygen demand (COD), biological oxygen demand in five days (BOD5), total phosphorus (TP), total nitrogen (TN)) and hydromorphology parameters (i.e., water quantity, channel change, morphology diversity) were used as the input variables to train and validate the SVM model. The sensitivity of the input variables for the prediction was examined by removing a variable from the SVM model. Results revealed that the SVM model reproduced the variation in bio-indicators of fish and algae communities well, based on the input variables. The sensitivity for the input variables applied in SVM showed that in the Taizi River the most sensitive variables for predicting macroinvertebrate and algae communities were channel change, DO, TN, and TP, while the most sensitive variables for predicting fish communities were DO and BOD5. This study proposed an effective method for predicting biological communities, which will improve freshwater quality and hydromorphology management schemes. The outputs can guide the decision-making process in river basin management, support the prioritization of actions and resource allocation, and help to monitor and evaluate the effectiveness of interventions. [ABSTRACT FROM AUTHOR]

High-throughput RNA sequencing (RNA-seq) provides a comprehensive picture of the transcriptome, including the identity, structure, quantity, and variability of expressed transcripts in cells, through the assembly of sequenced short RNA-seq reads. Although the reference-based approach guarantees the high quality of the resulting transcriptome, this approach is only applicable when the relevant reference genome is present. Here, we developed a pseudo-reference-based assembly (PRA) that reconstructs a transcriptome based on a linear regression function of the optimized mapping parameters and genetic distances of the closest species. Using the linear model, we reconstructed transcriptomes of four different aves, the white leg horn, turkey, duck, and zebra finch, with the Gallus gallus genome as a pseudo-reference, and of three primates, the chimpanzee, gorilla, and macaque, with the human genome as a pseudo-reference. The resulting transcriptomes show that the PRAs outperformed the de novo approach for species with within about 10% mutation rate among orthologous transcriptomes, enough to cover distantly related species as far as chicken and duck. Taken together, we suggest that the PRA method can be used as a tool for reconstructing transcriptome maps of vertebrates whose genomes have not yet been sequenced. [ABSTRACT FROM AUTHOR]

Kv1.5 (also known as KCNA5) is a protein encoded by the KCNA5 gene, which belongs to the voltage-gated potassium channel, shaker-related subfamily. Recently, a number of studies have suggested that Kv1.5 is overexpressed in numerous cancers and plays crucial roles in cancer development. However, until now, the expression and functions of Kv1.5 in osteosarcoma are still unclear. To characterize the potential biological functions of Kv1.5 in osteosarcoma, herein, we examined the expression levels of Kv1.5 in osteosarcoma cells and tissues using quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and immunohistochemistry assays. Four short hairpin RNAs (shRNAs) targeting Kv1.5 were designed and homologous recombination technology was used to construct pGeneSil-Kv1.5 vectors. In addition, the vectors were transfected into osteosarcoma MG63 cells and Kv1.5 mRNA level was measured by qRT-PCR and the Kv1.5 protein level was examined by western blot. We also examined the effects of Kv1.5 silencing on proliferation, cell cycle and apoptosis of the osteosarcoma cells using CCK-8, colony formation, flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays. Our results showed that Kv1.5 was aberrantly expressed in osteosarcoma and that the synthesized shRNA targeting Kv1.5 reduced Kv1.5 mRNA and protein expression effectively. Silencing Kv1.5 expression in the osteosarcoma cells significantly inhibited the proliferation of osteosarcoma cells, induced cell cycle arrest at G0/G1 phase, and induced cell apoptosis through up-regulation of p21, p27, Bax, Bcl-XL and caspase-3 and down-regulation of cyclins A, cyclins D1, cyclins E, Bcl-2 and Bik. In summary, our results indicate that Kv1.5 silencing could suppress osteosarcoma progression through multiple signaling pathways and suggest that Kv1.5 may be a novel target for osteosarcoma therapeutics. [ABSTRACT FROM AUTHOR]

Recently, a member of the voltage-dependent potassium channel (Kv) family, the Ether à go-go 1 (Eag1) channel was found to be necessary for cell proliferation, cycle progression and tumorigenesis. However, the therapeutic potential of the Eag1 channel in osteosarcoma remains elusive. In the present study, a recombinant adenovirus harboring shRNA against Eag1 was constructed to silence Eag1 expression in human osteosarcoma MG-63 cells. We observed that Eag1-shRNA inhibited the proliferation and colony formation of MG-63 cells due to the induction of G1 phase arrest. Moreover, in vivo experiments showed that Eag1-shRNA inhibited osteosarcoma growth in a xenograft nude mice model. In addition, selective inhibition of Eag1 significantly decreased the expression levels of cyclin D1 and E. Taken together, our data suggest that the Eag1 channel plays a crucial role in regulating the proliferation and cell cycle of osteosarcoma cells, and represents a new and effective therapeutic target for osteosarcoma. [ABSTRACT FROM AUTHOR]

Deregulation of voltage-gated potassium channel subunit Kv1.3 has been reported in many tumors. Kv1.3 promotes tumorigenesis by enhancing cell proliferation while suppressing apoptosis. However, the expression and function of Kv1.3 in osteosarcoma are unknown. In the present study, we detected the expression of Kv1.3 in human osteosarcoma cells and tissues by RT-PCR, Western blot and immunohistochemistry. We further examined cell proliferation and apoptosis in osteosarcoma MG-63 cells and xenografts following knockdown of Kv1.3 by short hairpin RNA (shRNA). We found that Kv1.3 was upregulated in human osteosarcoma. Knockdown of Kv1.3 significantly suppressed cell proliferation and increased apoptosis as demonstrated by enhanced cleavage of poly (ADP-ribose) polymerase (PARP) and the activation of Caspase-3/7. Furthermore, adenovirus delivered shRNA targeting Kv1.3 significantly inhibited the growth of MG-63 xenografts. Taken together, our results suggest that Kv1.3 is a novel molecular target for osterosarcoma therapy. [ABSTRACT FROM AUTHOR]

Ether à go-go 1 (Eag1) channel is overexpressed in a variety of cancers but the therapeutic potential of Eag1 in osteosarcoma remains elusive. In this study, we constructed an Ad5-Eag1-shRNA vector and evaluated its efficiency for Eag1 knockdown and its effects on osteosarcoma. Our results showed that Ad5-Eag1-shRNA had high interference efficiency of Eag1 expression and suppressed osteosarcoma growth both in vitro and in vivo. To explore the molecular mechanism underlying tumor growth inhibition induced by Eag1 silencing, the intratumoral microvessel density (MVD) was assessed by CD31 staining and the expression of vascular endothelial growth factor (VEGF) was detected by Western blot analysis. We found that Eag1 silencing led to decreased angiogenesis and VEGF expression in the xenograft model of osteosarcoma. Finally, we detected a time-dependent decrease in VEGF expression and considerably reduced phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) activation in osteosarcoma cells treated by Eag1 shRNA. Taken together, our results suggest that Eag1 silencing inhibits tumor growth and angiogenesis in osteosarcoma via the down regulation of VEGF/PI3K/AKT signaling. [ABSTRACT FROM AUTHOR]

Houttuynia cordata is an important traditional Chinese herb with unresolved genetics and taxonomy, which lead to potential problems in the conservation and utilization of the resource. Inter-simple sequence repeat (ISSR) markers were used to assess the level and distribution of genetic diversity in 226 individuals from 15 populations of H. cordata in China. ISSR analysis revealed low genetic variations within populations but high genetic differentiations among populations. This genetic structure probably mainly reflects the historical association among populations. Genetic cluster analysis showed that the basal clade is composed of populations from Southwest China, and the other populations have continuous and eastward distributions. The structure of genetic diversity in H. cordata demonstrated that this species might have survived in Southwest China during the glacial age, and subsequently experienced an eastern postglacial expansion. Based on the results of genetic analysis, it was proposed that as many as possible targeted populations for conservation be included [ABSTRACT FROM AUTHOR]

Mutations in the PRRT2 gene are the main cause for a group of paroxysmal neurological diseases including paroxysmal kinesigenic dyskinesia, episodic ataxia, benign familial infantile seizures, and hemiplegic migraine. In the mature central nervous system, the protein has both a functional and a structural role at the synapse. Indeed, PRRT2 participates in the regulation of neurotransmitter release, as well as of actin cytoskeleton dynamics during synaptogenesis. Here, we show a role of the protein also during early stages of neuronal development. We found that PRRT2 accumulates at the growth cone in cultured hippocampal neurons. Overexpression of the protein causes an increase in the size and the morphological complexity of growth cones. In contrast, the growth cones of neurons derived from PRRT2 KO mice are smaller and less elaborated. Finally, we demonstrated that the aberrant shape of PRRT2 KO growth cones is associated with a selective alteration of the growth cone actin cytoskeleton. Our data support a key role of PRRT2 in the regulation of growth cone morphology during neuronal development. [ABSTRACT FROM AUTHOR]

A new colorimetric and fluorescence probe NRSH based on Nile-red chromophore for the detection of biothiols has been developed, exhibiting high selectivity towards biothiols over other interfering species. NRSH shows a blue shift in absorption peak upon reacting with biothiols, from 587 nm to 567 nm, which induces an obvious color change from blue to pink and exhibits a 35-fold fluorescence enhancement at 645 nm in red emission range. NRSH displays rapid (<1 min) response for H2S, which is faster than other biothiols (>5 min). The detection limits of probe NRSH towards biothiols are very low (22.05 nM for H2S, 34.04 nM for Cys, 107.28 nM for GSH and 113.65 nM for Hcy). Furthermore, NRSH is low cytotoxic and can be successfully applied as a bioimaging tool for real-time monitoring biothiols in HeLa cells. In addition, fluorescence mechanism of probe NRSH is further understood by theoretical calculations. [ABSTRACT FROM AUTHOR]

In real applications, obtained depth images are incomplete; therefore, depth image inpainting is studied here. A novel model that is characterised by both a low-rank structure and nonlocal self-similarity is proposed. As a double constraint, the low-rank structure and nonlocal self-similarity can fully exploit the features of single-depth images to complete the inpainting task. First, according to the characteristics of pixel values, we divide the image into blocks, and similar block groups and three-dimensional arrangements are then formed. Then, the variable splitting technique is applied to effectively divide the inpainting problem into the sub-problems of the low-rank constraint and nonlocal self-similarity constraint. Finally, different strategies are used to solve different sub-problems, resulting in greater reliability. Experiments show that the proposed algorithm attains state-of-the-art performance. [ABSTRACT FROM AUTHOR]

The treatment of traumatic brain injury (TBI) remains a challenge due to limited knowledge about the mechanisms underlying neuronal regeneration. This current study compared the expression of WNT genes during regeneration of injured cortical neurons. Recombinant WNT3A showed positive effect in promoting neuronal regeneration via in vitro, ex vivo, and in vivo TBI models. Intranasal administration of WNT3A protein to TBI mice increased the number of NeuN+ neurons without affecting GFAP+ glial cells, compared to control mice, as well as retained motor function based on functional behavior analysis. Our findings demonstrated that WNT3A, 8A, 9B, and 10A promote regeneration of injured cortical neurons. Among these WNTs, WNT3A showed the most promising regenerative potential in vivo, ex vivo, and in vitro. [ABSTRACT FROM AUTHOR]

Yeonsan Ogye is a rare Korean domestic chicken breed whose entire body, including feathers and skin, has a unique black coloring. Although some protein-coding genes related to this unique feature have been examined, non-coding elements have not been widely investigated. Thus, we evaluated coding and non-coding transcriptome expression and identified long non-coding RNAs functionally linked to protein-coding genes in Ogye. High-throughput RNA sequencing and DNA methylation sequencing were performed to profile the expression of 14,264 Ogye protein-coding and 6900 long non-coding RNA (lncRNA) genes and detect DNA methylation in 20 different tissues of an individual Ogye. Approximately 75% of Ogye lncRNAs and 45% of protein-coding genes showed tissue-specific expression. For some genes, tissue-specific expression levels were inversely correlated with DNA methylation levels in their promoters. Approximately 39% of tissue-specific lncRNAs displayed functional associations with proximal or distal protein-coding genes. Heat shock transcription factor 2-associated lncRNAs appeared to be functionally linked to protein-coding genes specifically expressed in black skin tissues, more syntenically conserved in mammals, and differentially expressed in black relative to in white tissues. Pending experimental validation, our findings increase the understanding of how the non-coding genome regulates unique phenotypes and can be used for future genomic breeding of chickens. [ABSTRACT FROM AUTHOR]

High-throughput RNA sequencing (RNA-seq) provides a comprehensive picture of the transcriptome, including the identity, structure, quantity, and variability of expressed transcripts in cells, through the assembly of sequenced short RNA-seq reads. Although the reference-based approach guarantees the high quality of the resulting transcriptome, this approach is only applicable when the relevant reference genome is present. Here, we developed a pseudo-reference-based assembly (PRA) that reconstructs a transcriptome based on a linear regression function of the optimized mapping parameters and genetic distances of the closest species. Using the linear model, we reconstructed transcriptomes of four different aves, the white leg horn, turkey, duck, and zebra finch, with the Gallus gallus genome as a pseudo-reference, and of three primates, the chimpanzee, gorilla, and macaque, with the human genome as a pseudo-reference. The resulting transcriptomes show that the PRAs outperformed the de novo approach for species with within about 10% mutation rate among orthologous transcriptomes, enough to cover distantly related species as far as chicken and duck. Taken together, we suggest that the PRA method can be used as a tool for reconstructing transcriptome maps of vertebrates whose genomes have not yet been sequenced.