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Main conclusion: Differentially expressed microRNAs were found associated with the development of chasmogamous and cleistogamous flowers in Viola prionantha, revealing potential roles of microRNAs in the developmental evolution of dimorphic flowers. In Viola prionantha, chasmogamous (CH) flowers are induced by short daylight, while cleistogamous (CL) flowers are triggered by long daylight. How environmental factors and microRNAs (miRNAs) affect dimorphic flower formation remains unknown. In this study, small RNA sequencing was performed on CH and CL floral buds at different developmental stages in V. prionantha, differentially expressed miRNAs (DEmiRNAs) were identified, and their target genes were predicted. In CL flowers, Viola prionantha miR393 (vpr-miR393a/b) and vpr-miRN3366 were highly expressed, while in CH flowers, vpr-miRN2005, vpr-miR172e-2, vpr-miR166m-3, vpr-miR396f-2, and vpr-miR482d-2 were highly expressed. In the auxin-activated signaling pathway, vpr-miR393a/b and vpr-miRN2005 could target Vpr-TIR1/AFB and Vpr-ARF2, respectively, and other DEmiRNAs could target genes involved in the regulation of transcription, e.g., Vpr-AP2-7. Moreover, Vpr-UFO and Vpr-YAB5, the main regulators in petal and stamen development, were co-expressed with Vpr-TIR1/AFB and Vpr-ARF2 and showed lower expression in CL flowers than in CH flowers. Some V. prionantha genes relating to the stress/defense responses were co-expressed with Vpr-TIR1/AFB, Vpr-ARF2, and Vpr-AP2-7 and highly expressed in CL flowers. Therefore, in V. prionantha, CH–CL flower development may be regulated by the identified DEmiRNAs and their target genes, thus providing the first insight into the formation of dimorphic flowers in Viola. [ABSTRACT FROM AUTHOR]

Carbon emission trading scheme (ETS) policy is a quota-based market-motivated environmental regulation policy that by transforming environmental responsibility of enterprises into self-consciousness behavior induces green innovation behavior in enterprises and influences the level of regional green innovation. Based on panel data on green patents in 30 Chinese provinces from 2010 to 2019, the paper uses six Chinese pilot provinces for ETS as the treatment group to investigate the induced effects of Chinese ETS policy on the quantity and quality of green technology innovation using difference in difference model and analyzes the effects of Chinese ETS policy on green technology innovation in different pilot regions using a synthetic control method. The findings indicate that (1) compared with non-pilot areas, the carbon emission trading policies in pilot areas can induce green technology innovation activities. (2) In all pilot regions, ETS policies significantly promoted the quantity and quality of green technology innovation, but the quantity promotion effect was significantly better than the quality promotion effect, and the low-quality promotion effect was better than the high-quality promotion effect. (3) In terms of individual pilot region, ETS policies in Guangdong, Hubei and Tianjin significantly promoted the quantity of green technology innovation and low-quality green technology innovation, but significantly inhibited or suppressed high-quality green technology innovation in a short term. This paper not only enriches the research on environmental equity trading policies and green technology innovation theoretically, but also provides empirical evidence for the effectiveness of carbon emission trading schemes pilots program in China. [ABSTRACT FROM AUTHOR]

In the process of yielding biofuels from cellulose degradation, traditional enzymatic hydrolysis, such as β-glucosidase catalyzing cellobiose, can barely resolve the contradiction between cellulose degradation and bioenergy conservation. However, it has been shown that cellobiose phosphorylase provides energetic advantages for cellobiose degradation through a phosphorolytic pathway, which has attracted wide attention. Here, the cellobiose phosphorylase gene from Caldicellulosiruptor bescii (CbCBP) was cloned, expressed, and purified. Analysis of the enzymatic properties and kinetic mechanisms indicated that CbCBP catalyzed reversible phosphorolysis and had good thermal stability and broad substrate selectivity. In addition, the phosphorolytic reaction of cellobiose by CbCBP proceeded via an ordered Bi Bi mechanism, while the synthetic reaction proceeded via a ping pong Bi Bi mechanism. The present study lays the foundation for optimizing the degradation of cellulose and the synthesis of functional oligosaccharides. [ABSTRACT FROM AUTHOR]

In pursuit of the “double carbon” objectives, converting high-carbon thermal power plants into carbon capture power plants is recognized as an effective measure to mitigate carbon emissions. In order to improve the economy of the system, an electric hydrogen generation unit is introduced, and an economic dispatch strategy that considers the combination of a flexible carbon capture power plant and electric hydrogen generation is proposed. Firstly, the low-carbon principle of the flexible carbon capture plant is introduced, and secondly, the joint operation structure of the flexible carbon capture plant, pumped storage, and hydrogen generation is constructed in order to fully exploit the synergistic operation potential of the hydrogen and carbon capture plants. On this basis, an economic dispatch model with the objective of the lowest combined system cost of the sum of system operation cost, system carbon trading cost, hydrogen production revenue, and wind and light abandonment cost is established, fuzzy parameters are used to characterize the uncertainty levels of wind and light, fuzzy opportunity constraints are established, and the model is solved using an improved sparrow search algorithm. The results of the example show that the proposed model reduces the comprehensive cost by 20.9% and carbon emissions by 61.77% compared with the existing model, which has significant low-carbon economic benefits. [ABSTRACT FROM AUTHOR]

Purpose: Our purpose was to explore pupil light response (PLR) with respect to the change in sensitivity of photoreceptors during various dark adaptation phases and to determine the optimal duration of dark adaptation time before the PLR. Methods: The PLR was recorded in 15 healthy subjects and three patients with neural or retinal vision loss after 1-sec blue and red light stimuli of 1, 10, and 100 cd/m. The PLR was repeated nine times at different checkpoints during the 40-minute dark adaptation. The transient contraction amplitude, sustained contraction amplitude, and relative sustained contraction ratio of the PLR were analyzed. Results: The increase in the transient contraction amplitude during the entire dark adaptation process was significant (changing up to 45.1 %) in the initial phase of dark adaptation under different stimulus conditions. The changes in the sustained contraction amplitude and the relative sustained contraction ratio were substantial (changing up to 71.0 % and 37.2 % from 1 to 20 minutes of dark adaptation, respectively) under high-intensity blue illumination. The inflection point of the contraction curves in the dark adaptation was 15 or 20 minutes. The patients' PLR results changed in a similar manner. Conclusions: The changes in the sensitivity of different photoreceptors occurred at different rates, and the contraction amplitude of the PLR was significantly affected by the dark adaptation duration. So 20 minutes of dark adaptation before PLR testing was suggested to achieve a consistent and stable pupil response. The dark adaptation effect should be put into consideration when comparing the results from different phases of the PLR test. [ABSTRACT FROM AUTHOR]

Focuses on the study of gene function via manipulation of mouse genome. The high homology between human and mouse genomes that allows a disease model to be formed; Use of a chemical mutagen ethylnitrosourea (ENU) to create germ cell mutations in male mice; Screening of the first generation of mutated mice for abnormal phenotypes on gross morphology, behavior, learning and memory, auditory brainstem response (ABR), electrocardiogram (ECG), electroetinogram (ERG), flash-visual evoked potential F-VEP), home mineral density, and blood sugar level; Number of mice with specific dominant abnormalities; High frequency of fur color changes, eye defects and hearing loss; Finding that abnormalities related to metabolism are least frequent; Sex preference observed in mice; Suggestion that behavior abnormalities of G1 mice are not inheritable because of multi-gene control; Implications of the research for cloning disease-related genes.

The E( spl) mγ gene in Drosophila is a regulatory target gene downstream of the Notch pathway. BmE( spl) mγ ( Bombyx mori, E( spl) mγ) is an ortholog of the Drosophila E( spl) mγ gene, and the gene encodes a protein with 248 amino acid residues. This gene was cloned and overexpressed in Escherichia coli BL21(DE3). The recombinant protein was purified and subsequently used to generate a rabbit polyclonal antibody. Western blotting analyses showed that BmE( spl) mγ expression is high in pupa and egg, and low in larva and moth. In the fifth instar larva, the protein levels are high in head, epidermis, sexual gland, trachea, and the fatbody and low in the Malpighian tubule, hemolymph, gut, and silk gland. The further immunohistochemical analyses also showed higher BmE( spl) mγ expression in the head of fifth instar larva and pupa. Of the four moth parts studied, the thorax had the highest expression level. Thus, BmE(spl)mγ might be associated with neurogenesis in silkworm. Furthermore, DAPT (a γ-secretase inhibitor and an indirect inhibitor of Notch) blocking experiments showed that higher concentrations of the blocking agent and a longer processing time reduce the transcription levels of the BmE( spl) mγ gene, demonstrating that the silkworm BmE( spl) mγ gene is associated with the Notch signal pathway. These findings suggest that the function of BmE( spl) mγ may be similar to that of its Drosophila homolog. [ABSTRACT FROM AUTHOR]

Due to the lack of an appropriate animal model, few studies have addressed the integration of visual and vestibular information in the visual system. Using a mouse model with a visual defect (retinal degeneration fast, rdf), we have verified that the prepositus hypoglossal nucleus (PrH) and the Kooy cap of the inferior olive medial nucleus (IOK) are key regions in which visual and vestibular information integrate. Although the integration regions were identified, the precise mechanisms of integration require further investigation. The rdf mice and wild-type Kunming mice were randomly assigned to experimental and control subgroups, respectively. Mice in the experimental groups were exposed to rotary motion for 30 min three times at 24-h intervals, whereas mice in the control groups were not exposed to rotary motion. Differences in the number of calcitonin gene-related peptide positive (CGRP-positive) and choline acetyltransferase positive (ChAT-positive) neurons in the vestibular-related nucleus populations of two types of mice were determined. After rotatory stimulus, the number of CGRP-positive and ChAT-positive neurons in the PrH and the IOK was significantly less in rdf mice compared with that in wild-type mice. There were differences in the number of CGRP-positive and ChAT-positive neurons in the other vestibular-related regions, but the differences were not significant, except the difference in the number of ChAT-positive neurons in the medial vestibular nucleus. The expression patterns of CGRP and ChAT were similar to that of Fos in the vestibular-related regions in the two types of mice after rotatory stimulus. The number of CGRP-positive and ChAT-positive neurons and the number of active nerve cells were consistent in those regions in the two types of mice after rotary stimulus. Therefore, we speculated that CGRP and Ach generated and released by neurons in the PrH and the IOK may play roles in the sensory integration of visual and vestibular information in mice. [ABSTRACT FROM AUTHOR]

The presently available expression tools and vectors (e.g., eukaryotic expression vectors and the adenovirus expression system) for studying the functional genes in Bombyx mori are insufficient. The baculovirus expression system is only used as a protein production tool; therefore, recombinant proteins expressed by B. mori using the baculovirus expression system equipped with a polyhedrin promoter cannot be used for in vivo research applications. In this work, we constructed and screened a eukaryotic expression vector for silkworm cells The EGFP and B. mori Argonaute2 proteins were found to be efficiently expressed using the screened pIEx-1 vector with the FuGENE 6 transfection reagent. Additionally, we constructed a novel nucleopolyhedrovirus ie1-Bacmid expression system for the production of recombinant protein; we then used the system to highly express the EGFP and B. mori Argonaute2 proteins. In this system, the protein of interest can be efficiently expressed 13 h after infection by controlling the B. mori nucleopolyhedrovirus immediate early ie1 promoter. The ie1-Bacmid system provides a powerful 'adenovirus-like' expression tool; not only can the tool be used to study baculovirus molecular biology for the silkworm but it is also useful in other research applications as well, such as the study of gene functions involved in cellular physiological processes. [ABSTRACT FROM AUTHOR]

Family 48 glycoside hydrolases (cellobiohydrolases) are among the most important cellulase components for crystalline cellulose hydrolysis mediated by cellulolytic bacteria. Open reading frame (Cphy_3368) of Clostridium phytofermentans ISDg encodes a putative family 48 glycoside hydrolase (CpCel48) with a family 3 cellulose-binding module. CpCel48 was successfully expressed as two soluble intracellular forms with or without a C-terminal His-tag in Escherichia coli and as a secretory active form in Bacillus subtilis. It was found that calcium ion enhanced activity and thermostability of the enzyme. CpCel48 had high activities of 15.1 U μmol−1 on Avicel and 35.9 U μmol−1 on regenerated amorphous cellulose (RAC) with cellobiose as a main product and cellotriose and cellotetraose as by-products. By contrast, it had very weak activities on soluble cellulose derivatives (e.g., carboxymethyl cellulose (CMC)) and did not significantly decrease the viscosity of the CMC solution. Cellotetraose was the smallest oligosaccharide substrate for CpCel48. Since processivity is a key characteristic for cellobiohydrolases, the new initial false/right attack model was developed for estimation of processivity by considering the enzyme's substrate specificity, the crystalline structure of homologous Cel48 enzymes, and the configuration of cellulose chains. The processivities of CpCel48 on Avicel and RAC were estimated to be ∼3.5 and 6.0, respectively. Heterologous expression of secretory active cellobiohydrolase in B. subtilis is an important step for developing recombinant cellulolytic B. subtilis strains for low-cost production of advanced biofuels from cellulosic materials in a single step. [ABSTRACT FROM AUTHOR]