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In industrial practice, smithsonite flotation separation and purification are nearly invariably conducted in highly alkaline environments. According to latest studies, sodium carbonate is a cheap, sustainable, stable, and safe substitute pH modifier that additionally assists with deep extraction recovery of smithsonite. In this work, the influence of carbonate as a pH modifier on smithsonite flotation behavior was comprehensively explored through flotation experiments, contact angle tests, X-ray photoelectron spectroscopy (XPS) investigations, and density functional theory (DFT) calculations. In comparison to sodium hydroxide, smithsonite exhibits far better floatability and hydrophobicity in the carbonate system, as demonstrated by the results of micro-flotation and contact angle experiments. XPS demonstrates that the underlying reason of the distinct pH modifications of smithsonite floatability in the carbonate system is the creation of different zinc-containing compounds, with the highly reactive CO32-forming a Zn5(CO3)2(OH)6complex with Zn atoms at pH 10.5. Comprehensive DFT calculations further demonstrated that the hybridization reactions between Zn 2 s, O 2 s, and O 2p orbitals and the formation of stable Zn-O covalent bonds between OH-and Zn atoms shielded the preferential adsorption of oleate (OL-) on the smithsonite surface. Uniquely, the ionic bonding generated by carbonate is distinguished by the formation of a low-bonding-capacity Zn-O chemical bond, causing it susceptible to breaking during adsorption competition and allowing OL-to adsorb preferentially on Zn sites.

Many marine invertebrate phyla are characterized by indirect development. These animals transit from planktonic larvae to benthic spats via settlement and metamorphosis, which contributes to their adaption to the marine environment. Studying the biological process of metamorphosis is, thus, key to understanding the origin and evolution of indirect development. Although numerous studies have been conducted on the relationship between metamorphosis and the marine environment, microorganisms, and neurohormones, little is known about gene regulation network (GRN) dynamics during metamorphosis. Metamorphosis-competent pediveligers of the Pacific oyster Crassostrea gigaswere assayed in this study. By assaying gene expression patterns and open chromatin region changes of different samples of larvae and spats, the dynamics of molecular regulation during metamorphosis were examined. The results indicated significantly different gene regulation networks before, during and post-metamorphosis. Genes encoding membrane-integrated receptors and those related to the remodeling of the nervous system were upregulated before the initiation of metamorphosis. Massive biogenesis, e.g., of various enzymes and structural proteins, occurred during metamorphosis as inferred from the comprehensive upregulation of the protein synthesis system post epinephrine stimulation. Hierarchical downstream gene networks were then stimulated. Some transcription factors, including homeobox, basic helix–loop–helix and nuclear receptors, showed different temporal response patterns, suggesting a complex GRN during the transition stage. Nuclear receptors, as well as their retinoid X receptor partner, may participate in the GRN controlling oyster metamorphosis, indicating an ancient role of the nuclear receptor regulation system in animal metamorphosis.

The fine scheelite flotation using garnet and glass beads as agitation medium was investigated through slurry rheology and froth property analysis. The apparent viscosity of fine scheelite, calcite and quartz (−20 μm) slurry were measured and the corresponding scheelite flotation behaviours, froth water recovery and froth height were studied. It was found that calcite slurry could aggregate into network structures and exhibit much higher apparent viscosity at the vicinity of pH 8.5–9.0 than scheelite and quartz (scheelite, calcite, and quartz slurry at 20.34, 38.66, and 14.58 mPa·s, respectively). Agitation medium containing garnet and glass beads could reduce the slurry apparent viscosity by effectively dispersing the calcite network structures in flotation slurry, and improve the fine scheelite flotation selectivity. As the apparent viscosity was reduced, the froth water recovery decreased from 24.33% to 6.37% and initial froth height of the flotation froth decreased from 69.6 to 8.7 mm, and finally results in increase in separation efficiency from 23.10% to 31.96%. The results could be potentially used in flotation of fine minerals by applying agitation medium to improve the process selectivity.

Investigation on the mineral−water interactions is crucial for understanding the subsequent interfacial reactions. Currently, the hydration mechanisms of smithsonite are still obscure. In this paper, the adsorption of H2O at different coverage rates on smithsonite (101) surface was innovatively investigated using density-functional theory (DFT) calculations and molecular dynamics (MD) simulations by analyzing adsorption model, interaction energy, atomic distance, density of state, electron density difference, concentration profile, radial distribution function and self-diffusion coefficient. We found that single H2O preferred to be dissociated on smithsonite (101) surface via the interaction of surface Zn with the Ow of H2O and H-bond between Hw of H2O and surface Os. However, dissociation adsorption and molecular adsorption coexisted on the smithsonite surface at a high coverage rate of H2O, and dissociation adsorption remained the main adsorption mechanism. Moreover, we found the interaction between smithsonite surface and H2O was weakened as a function of H2O coverage, which was because the presence of interlayer H2O and different layers of H2O decreased the reactivity of the smithsonite surface. The H2O is mainly adsorbed on the smithsonite surface by forming three layers of H2O (about 10–15 Å), with the ordering degree gradually decreasing.

Epigenetic mechanisms such as DNA methylation have the potential to affect organism acclimatization and adaptation to environmental changes by influencing their phenotypic plasticity; however, little is known about the role of methylation in the adaptive phenotypic divergence of marine invertebrates. Therefore, in this study, a typical intertidal species, the Pacific oyster (Crassostrea gigas), was selected to investigate the epigenetic mechanism of phenotypic plasticity in marine invertebrates. Intertidal and subtidal oysters subjected to one-generation common garden experiments and exhibited phenotypic divergence were used. The methylation landscape of both groups of oysters was investigated under temperate and high temperature. The two tidal oysters exhibited divergent methylation patterns, regardless of the temperature, which was mainly original environment-induced. Intertidal samples exhibited significant hypomethylation and more plasticity of methylation in response to heat shock, while subtidal samples showed hypermethylation and less plasticity. Combined with RNA-seq data, a positive relationship between methylation and expression in gene bodies was detected on a genome-wide scale. In addition, approximately 11% and 7% of differentially expressed genes showed significant methylation variation under high temperatures in intertidal and subtidal samples, respectively. Genes related to apoptosis and organism development may be regulated by methylation in response to high temperature in intertidal oysters, whereas oxidation-reduction and ion homeostasis-related genes were involved in subtidal oysters. The results also suggest that DNA methylation mediates phenotypic divergence in oysters adapting to different environments. This study provides new insight into the epigenetic mechanisms underlying phenotypic plasticity in adaptation to rapid climate change in marine organisms.

In this work, a hierarchical BiOBr/Bi24O31Br10heterojunction is prepared for the first time from a bismuth MOF (Bi-BTC) by a facile bromination–annealing route. Since cetyltrimethylammonium bromide (CTAB) is used as the Br element source, the heterojunction constructed of BiOBr and Bi24O31Br10nanosheets maintains the rod-like morphology of the original MOF. In photocatalytic degradation tests, the BiOBr/Bi24O31Br10heterojunction exhibits much higher photocatalytic activity than pure Bi2O3, and the heterojunctions annealed at 450 °C show the best photocatalytic activity among samples prepared at various temperatures. The heterojunction also shows good pH adaptability, good reusability, and structural stability for RhB degradation, and the TOC results and full UV-vis spectra confirm its good mineralization performance under visible-light irradiation. Based on the photo-electrochemical characterization and free radical tests, a photocatalytic enhancement mechanism over the heterojunction and different photocatalytic reactions in the presence of photo-induced h+, O2−and 1O2are reasonably proposed.

The Pacific abalone (Haliotis discus hannai) is widely cultivated in East Asian countries. Aquaculture of this species has become a thriving industry in China, with adequate seed production being a key contributing factor. However, maintaining sufficient diatom abundance during the nursery phase remains challenging. In this study, we assessed a transfer nursery culture method that involves prolonged cultivation with a sufficient diatom supply. This method involved treating postlarvae on diatom-depleted plates with a garlic juice (GJ) solution to facilitate detachment, followed by transfer to newly diatom-precoated plates for further growth in the nursery. We investigated the effects of garlic juice concentration (GJC) and animal size on detachment and mortality rates using a two-factor design. Our negative binomial regression analysis uncovered significant impacts of both factors and their interactions on the target traits. We noticed that the optimal GJC for smaller groups of abalone postlarvae (2.2 ± 1.0mm) was 0.7%, while for larger groups (3.8 ± 2.2mm), it increased to 1.0%. Notably, suitable GJC concentrations during post-treatment recovery resulted in no apparent mortality in Pacific abalone postlarvae. Our study demonstrated the effectiveness of the transfer nursery method, showing an improvement of over ~1.1mm in shell length and a 43.1% increase in survival during a 30-day experiment. Our study presents a significant advancement, as it likely introduces the first reported method of large-scale postlarval removal of H. discus hannaifor prolonged nursery periods with sufficient diatom provision. The integration of GJ treatment and the transfer nursery method exhibited promising results, highlighting the benefits of its application for enhancing husbandry procedures, nursery management, and the overall industrial productivity of Pacific abalone.

Transcriptional plasticity interacts with natural selection in complex ways and is crucial for the survival of species under rapid climate change. How 3D genome architecture affects transcriptional plasticity and its interaction with genetic adaptation are unclear. We transplanted estuarine oysters to a new environment and found that genes located in active chromatin regions exhibited greater transcriptional plasticity, and changes in these regions were negatively correlated with selective signals. This indicates a trade-off between 3D active regions and selective signals in shaping plastic responses to a new environment. Specifically, a mutation, lincRNA, and changes in the accessibility of a distal enhancer potentially affect its interaction with the ManⅡagene, which regulates the muscle function and survival of oysters. Our findings reveal that 3D genome architecture compensates for the role of genetic adaptation in environmental response to new environments and provide insights into synergetic genetic and epigenetic interactions critical for fitness-related trait and survival in a model marine species.

Flexible electrochromic energy storage devices (FECESDs) for powering flexible electronics have attracted considerable attention. Silver nanowires (AgNWs) are one kind of the most promising flexible transparent electrodes (FTEs) materials for the emerging flexible devices. Currently, fabricating FECESD based on AgNWs FTEs is still hindered by their intrinsic poor electrochemical stability. To address this issue, a hybrid AgNWs/Co(OH)2/PEDOT:PSS electrode is proposed. The PEDOT:PSS could not only improve the resistance against electrochemical corrosion of AgNWs, but also work as functional layer to realize the color-changing and energy storage properties. Moreover, the Co(OH)2interlayer further improved the color-changing and energy storage performance. Based on the improvement, we assembled the symmetrical FECESDs. Under the same condition, the areal capacitance (0.8 mF cm−2) and coloration efficiency (269.80 cm2C−1) of AgNWs/Co(OH)2/PEDOT:PSS FECESDs were obviously higher than AgNWs/PEDOT:PSS FECESDs. Furthermore, the obtained FECESDs exhibited excellent stability against the mechanical deformation. The areal capacitance remained stable during 1000 times cyclic bending with a 25 mm curvature radius. These results demonstrated the broad application potential of the AgNWs/Co(OH)2/PEDOT:PSS FECESD for the emerging portable and multifunctional electronics.

Oysters that occupy estuarine and intertidal habitats have well-developed stress tolerance mechanisms to tolerate harsh and dynamically changing environments. In this review, we summarize common pathways and genomic features in oyster that are responsive to environmental stressors such as temperature, salinity, hypoxia, air exposure, pathogens, and anthropogenic pollutions. We first introduce the key genes involved in several pathways, which constitute the molecular basis for adaptation to stress. We use genome analysis to highlight the strong cellular homeostasis system, a unique adaptive characteristic of oysters. Next, we provide a global view of features of the oyster genome that contribute to stress adaptation, including oyster-specific gene expansion, highly inducible expression, and functional divergence. Finally, we review the consequences of interactions between oysters and the environment from ecological and evolutionary perspectives by discussing mass mortality and adaptive divergence among populations and related species of the genus Crassostrea. We conclude with prospects for future study.

Abstract: We conducted a complete diallel cross among three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino to determine the heterosis and the combining ability of growth traits at the spat stage. The three populations were collected from Qingdao (Q) and Dalian (D) in China, and Miyagi (M) in Japan. We measured the shell length, shell width, and total weight. The magnitude of the general combining ability (GCA) variance was more pronounced than the specific combining ability (SCA) variance, which is evidenced by both the ratio of the genetic component in total variation and the GCA/SCA values. The component variances of GCA and SCA were significant for all three traits (P<0.05), indicating the importance of additive and non-additive genetic effects in determining the expression of these traits. The reciprocal maternal effects (RE) were also significant for these traits (P<0.05). Our results suggest that population D was the best general combiner in breeding programs to improve growth traits. The DM cross had the highest heterosis values for all three traits.

Abstract: Microsatellites were screened in a backcross family of the Pacific oyster, Crassostrea gigas. Fifteen microsatellite loci were distinguishable and polymorphic with 6 types of allele-combinations. Null alleles were detected in 46.7% of loci, accounting for 11.7% of the total alleles. Four loci did not segregate in Mendelian Ratios. Three linkage groups were identified among 7 of the 15 segregating loci. Fluorescence-based automated capillary electrophoresis (ABI 310 Genetic Analyzer) that used to detect the microsatellite loci, has been proved a fast, precise, and reliable method in microsatellite genotyping.

The utilization of Ca ion as assistant depressant of CMC on talc has been widely reported. Thus, the study on the adsorption mechanism of Ca ion on talc surface is very crucial for understanding the performance of CMC on talc depression. In this paper, mechanism insights into hydrated Ca ion adsorption on talc (0 0 1) basal surface were creatively provided using DFT calculation. [Ca(H2O)6]2+and [Ca(OH)(H2O)3]+were determined as the effective hydrate components for Ca ion adsorption, and the top O site was the most favorable position for their adsorptions on talc surface. Furthermore, the adsorption mechanisms of [Ca(H2O)6]2+and [Ca(OH)(H2O)3]+on talc surface were found to be not the Ca-O chemical bond, but the hydrogen bonding formed by the H atom of the H2O ligand and the surface O atom. H2O acted like a bridge to connect them to the talc surface. Moreover, the hydrogen bonding was formed due to the hybridization of H 1s orbital with the O 2s, O 2p orbitals. Simultaneously, electrons transferred between the H atom and the surface O atom. This work provides theoretical insights into the Ca ion adsorption on talc surface, which can help deeply understand the talc flotation using CMC as depression.

Effects of inbreeding and maternity on early performance were studied in the Pacific abalone Haliotis discus hannaiusing two sets of 2 × 2 factorial crosses involving sister–brother mating. Parents from three full-sib families produced from two wild abalone populations (Japan and China) were used for the study. Metamorphic success and larval growth in four inbred (F = 0.25) and four outbred families were evaluated to 20 d postfertilization. In set I, inbreeding depression was 8.65% for metamorphic success, and-1.06, 3.25, and 4.98% for larval size at days 6, 10, and 20, respectively. In set II, inbreeding depression was 39.3% for metamorphic success, and 1.92, 4.99, and 3.37% for size at days 6, 10, and 20, respectively. Additionally, there were significant maternal effects on metamorphosis and larval size on day 6 (P< 0.01) in set I, which became insignificant at days 10 and 20. Maternal effects were absent in set II. The results of this study suggest that inbreeding at F = 0.25 significantly affects larval growth and greatly reduces metamorphic success in the Pacific abalone.

Mollusc shell matrix proteins (SMPs) are important functional components embedded in the shell and play a role in shell formation. A SMP (Pif177) was identified previously from the nacreous layer of the Japanese pearl oyster Pinctada fucata, and its cleavage products (named pfPif97 and pfPif80 proteins) were found to bind to the chitin framework and induce aragonite crystal formation and orient the c axis. In this study, a homologue of pfPif177 was cloned from the mantle of the Pacific oyster Crassostrea gigas, containing the homologue of pfPif97 only and not pfPif80. This finding hints at the large divergence in gene structure between the two species. This homologue (cgPif97) shares characteristics with pfPif97, and suggests that the biological functions of these two proteins may be similar. The expression pattern of cgPif97 in different tissues and development stages indicates that it may play an important role in shell formation of the adult oyster. The morphology of the inner shell surface was affected by injected siRNA of cgPif97 and the calcite laths of the shell became thinner and narrower when the siRNA dose increased, suggesting that the cgPif97 gene plays an important role in calcite shell formation in C. gigas. In conclusion, we found evidence that the Pif177 gene evolved very fast but still retains a similar function among species.