Mask-Moving-Lithography-Based High-Precision Surface Fabrication Method for Microlens Arrays.

Microlens arrays, as typical micro-optical elements, effectively enhance the integration and performance of optical systems. The surface shape errors and surface roughness of microlens arrays are the main indicators of their optical characteristics and determine their optical performance. In this study, a mask-moving-projection-lithography-based high-precision surface fabrication method for microlens arrays is proposed, which effectively reduces the surface shape errors and surface roughness of microlens arrays. The pre-exposure technology is used to reduce the development threshold of the photoresist, thus eliminating the impact of the exposure threshold on the surface shape of the microlens. After development, the inverted air bath reflux method is used to bring the microlens array surface to a molten state, effectively eliminating surface protrusions. Experimental results show that the microlens arrays fabricated using this method had a root mean square error of less than 2.8%, and their surface roughness could reach the nanometer level, which effectively improves the fabrication precision for microlens arrays.

Comparative Transcriptome and WGCNA Analysis Reveal Molecular Responses to Salinity Change in Larvae of the Iwagaki Oyster Crassostrea Nippona.

The Iwagaki oyster Crassostrea nippona is an important aquaculture species with significant potential for large-scale oyster farming. It is susceptible to the fluctuated salinity in the coastal area. In this study, we compared the transcriptome of Crassostrea nippona larvae under variant conditions with low-salinity stress (28, 20, 15, 10, and 5 practical salinity units (psu)) for 24 h. KEGG enrichment analysis of differentially expressed genes (DEGs) from pairwise comparisons identified several free amino acid metabolism pathway (taurine and hypotaurine, arginine and proline, glycine, and beta-alanine) contributing to the salinity change adaptation and activated "lysosome" and "apoptosis" pathway in response to the low-salinity stress (10 and 5 psu). Trend analysis revealed sustained upregulation of transmembrane transport-related genes (such as SLC family) and downregulation of ribosomal protein synthesis genes faced with decreasing salinities. In addition, 9 biomarkers in response to low-salinity stress were identified through weighted gene co-expression network analysis (WGCNA) and validated by qRT-PCR. Our transcriptome analysis provides a comprehensive view of the molecular mechanisms and regulatory networks underlying the adaptive responses of oyster larvae to hypo-salinity conditions. These findings contribute to our understanding of the complex biological processes involved in oyster resilience and adaptation to changing environmental conditions.

Effects of low salinity on hemolymph osmolality and transcriptome of the Iwagaki oyster, Crassostrea nippona.

Crassostrea nippona is a kind of oysters with great development value as it can be edible in summer for its late reproductive period. Salinity is one of the important limiting abiotic factors to the survival and distribution of this stenohaline species. To better understand the physiological and immunological response of C. nippona to varying environmental salinities, the effects of low salinity on the hemolymph osmolality and gill transcriptome were investigated in this study. The osmolality of hemolymph in vivo and surrounding water were assessed regularly over one week at five test salinities ranging from 5 psµ to 30 psµ. They reached osmotic equilibrium within hours above 15 psµ but remained hyperosmotic at 10 and 5 psµ for the whole sampling period. Through comparative transcriptome analysis, there were less differentially expressed genes (DEGs) in pairwise comparison of S1 (10 psµ) vs S3 (30 psµ) than in S2 (20 psµ) vs S3. KEGG enrichment analysis identified ubiquitin-mediated proteolysis and mitochondrial apoptosis pathway specifically enriched at 10 psµ. This study gained comprehensive insights on the low salinity response of C. nippona at the molecular level, which provide a theoretical basis for understanding the immune mechanism under low salinity stress.

First de novo transcriptome assembly of Iwagaki oyster, Crassostrea nippona, and comparative evolutionary analysis of salinity-stress response genes in Crassostrea oysters.

Crassostrea nippona is a commercially important oyster species in East Asia for it is edible during the summer when the other oyster species are unavailable. Salinity is one of the important limiting factors to the survival and distribution of this stenohaline species. In this study, 535 million reads (74G data) from C. nippona were produced and assembled into 66,742 transcripts. The number of 19,253 differentially expressed genes (DEGs) under salinity stress were identified as salinity stress-response genes. Through comparative evolutionary analysis in five Crassostrea species from East Asia, salinity stress-response genes were noticed to have higher adaptive evolution rates than other genes. This study presents the first de novo transcriptome of C. nippona. Furthermore, comparative evolutionary analysis implies that salinity plays an important role in speciation of Crassostrea species.