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Tributyl phosphate (TNBP), a new type of flame retardant, is an emerging pollutant and has been frequently detected in various matrices such as wastewater. Efficient removal of TNBP is critical for wastewater treatment. In this study, molecularly imprinted polymer (MIP) was prepared using precipitation polymerization for selective adsorption of TNBP. The results showed that MIP had a porous structure and formed effective imprinting cavities, which was primarily responsible for its superior adsorption ability. The adsorption of TNBP by MIP was carried out following both the pseudo-secondary kinetic model and the Langmuir isothermal adsorption model. MIP adsorbed TNBP rapidly and reached adsorption equilibrium within 30 min with 923 μmol g−1 at 298 K. The adsorption capacity and adsorption rate of MIP were respectively 2 and 5.49 times those of non-molecularly imprinted polymers. In addition, MIP could effectively counter disturbances from external parameters like temperature and pH, exhibiting strong environmental flexibility. MIP can specifically adsorb organophosphate esters, and can selectively adsorb TNBP under the interference of coexisting contaminants such as1,3-diphenylguanidine and isazofos. In actual bodies of water, MIP's highly selective adsorption of TNBP retains its advantage. The selective adsorption of MIP was mainly due to the common phosphate skeleton, and the specific substituent of organophosphate esters played an important role in the imprinting process. Hydrogen bonding might be involved in the polymerization process of TNBP with acrylamide and the adsorption process of TNBP by MIP.MIP exhibited good reuse efficiency, the total adsorption capacity decreased by no more than 25% after 7 reuse cycles. This study provides a simple and efficient method for selective removal of organophosphate from wastewater. [Display omitted] • MIP was synthesized with different templates, the synthesis system was optimized. • The adsorption equilibrium reached within 30 min, the q m was 923 μmol g−1 at 298 K. • MIP can selectively adsorb TNBP under the interference of DPG and isazofos. • MIP has good environmental adaptability and potential for practical application. • Hydrogen bonding may play a role in the adsorption and imprinting process. [ABSTRACT FROM AUTHOR]

Abstract Similar to other marine bivalves, Pinctada fucata martensii presents unsynchronized growth, which is one of the problems farmers currently face. However, the underlying mechanisms have not been studied. In the present study, pearl oyster P. f. martensii from cultured stocks were selected to produce a progeny stock. At 180 days, the stock was sorted by size, and fast- and slow-growing individuals were separately sampled. Then, metabolomic and transcriptomic approaches were applied to assess the metabolic and transcript changes between the fast- and slow-growing P. f. martensii groups and understand the mechanism underlying their unsynchronized growth. In the metabolomics assay, 30 metabolites were considered significantly different metabolites (SDMs) between the fast- and slow-growing groups and pathway analysis indicated that these SDMs were involved in 20 pathways, including glutathione metabolism; sulfur metabolism; valine, leucine, and isoleucine biosynthesis; and tryptophan metabolism. The transcriptome analysis of different growth groups showed 168 differentially expressed genes (DEGs) and pathway enrichment analysis indicated that DEGs were involved in extracellular matrix-receptor interaction, pentose phosphate pathway, aromatic compound degradation. Integrated transcriptome and metabolome analyses showed that fast-growing individuals exhibited higher biomineralization activity than the slow-growing group, which consumed more energy than the fast-growing group in response to environmental stress. Fast-growing group also exhibited higher digestion, anabolic ability, and osmotic regulation ability than the slow-growing group. This study is the first work involving the integrated metabolomic and transcriptomic analyses to identify the key pathways to understand the molecular and metabolic mechanisms underlying unsynchronized bivalve growth. Graphical abstract Unlabelled Image Highlights • Metabolomics and transcriptomic were applied to analyze the bivalve unsynchronized growth. • Fast-growing group hold high biomineralization activity. • Slow-growing group consumed more energy in response to environment stress. • Fast-growing group exhibited high digestion and anabolic ability. • Fast-growing group possessed high osmotic regulation ability. [ABSTRACT FROM AUTHOR]

Our study conducts an innovative analysis of the power grid from a network perspective, shedding light on crucial aspects of the wholesale electricity market in Texas. By employing a power system engineering model, we construct a transmission network representation, presenting a novel contribution to the economics literature. Through our analysis of the network matrix, we delve into the characteristics of the Texas power grid, specifically focusing on the structural changes resulting from the Competitive Renewable Energy Zone (CREZ) project and their impacts on nodal prices. The empirical analysis provides additional evidence that ignoring changes in the transmission grid leads to biased estimates of various coefficients. This includes the spatial dependence coefficient, as well as the coefficients associated with control variables such as wind production and load. These empirical findings underscore the significance and distinctive value of network analysis in studying power grids. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the oxidation and removal of As(III) from aqueous solutions by persulfate (PS) activated with zero valent iron (ZVI). Batch experiments were performed to examine the effects of pH, ZVI dosage and PS concentration on the oxidation and removal of As(III). The oxidation efficiency of As(III) (50 μM) was 96% in the presence of persulfate (5 mM) and ZVI (0.3 g/L) within 30 min. As(III) oxidation and removal efficiency was significantly affected with initial pH and increased with decreasing pH. It has been observed that complete oxidation of As(III) is obtained at pH 3.0 within 10 min. The results showed that the oxidation efficiency increased with an increase in ZVI dosage from 0.1 to 0.3 g/L and an increase in PS concentration from 0.5 to 5.0 mM. But further increase in ZVI amount and PS would result in decrease the oxidation of As(III). Electron paramagnetic resonance (EPR) technique combined with two kinds of radical scavenging agents such as tert-butyl alcohol (TBA) and ethanol (EtOH) has been employed to confirm that sulfate radicals (SO 4 − ) and hydroxyl radicals ( OH) were generated from PS activation with ZVI for As(III) removal. [ABSTRACT FROM AUTHOR]

Activated persulfate along with trace sulfate and hydroxyl radicals were found to be reactive oxygen species in copper oxide activated persulfate system in this study. Persulfate decomposition study revealed that activated persulfate was predominant instead of sulfate and hydroxyl radicals. The radical scavenger investigation supported this point and led to the surface activation mechanism of persulfate. The p -chloroaniline (PCA) degradation in copper oxide activated persulfate system in neutral and acidic condition provided the evidence of prime heterogeneous persulfate activation and minor homogeneous persulfate activation caused by dissolved copper ion. Electron Paramagnetic Resonance study indicated the generation of sulfate and hydroxyl radicals. Integrating all the experiment facts, it is proposed that activated persulfate was main reactive oxygen species generated on copper oxide surface, along with minor sulfate and hydroxyl radicals produced. Chloride ions showed no effect on PCA degradation in copper oxide activated persulfate system. While bicarbonate ions improved PCA degradation without pH adjustment (initial pH is about 3) and performed an inhibition effect when the initial pH was adjusted to neutral. These findings indicated the potential applicability of copper oxide for in situ chemical oxidation for two reasons: (1) ubiquitous chloride and bicarbonate ions showed no negative effect and (2) the slight radical generation avoid the persulfate consumption by non-pollutant reductive materials. [ABSTRACT FROM AUTHOR]

Analyses of the transcriptome and metabolome were conducted to clarify alterations of key genes and metabolites in pearl oysters following exposure to short-term hypoxic treatment. We totally detected 209 DEGs between the control and hypoxia groups. Enrichment analysis indicated the enrichment of GO terms including "oxidation-reduction process", "ECM organization", "chaperone cofactor-dependent protein refolding", and "ECM-receptor interaction" KEGG pathway by the DEGs. In addition, between the two groups, a total of 28 SDMs were identified, which were implicated in 13 metabolic pathways, such as "phenylalanine metabolism", "D-amino acid metabolism", and "aminoacyl-tRNA biosynthesis". Results suggest that pearl oysters are exposed to oxidative stress and apoptosis under short-term hypoxia. Also, pearl oysters might adapt to short-term hypoxic treatment by increasing antioxidant activity, modulating immune and biomineralization activities, maintaining protein homeostasis, and reorganizing the cytoskeleton. The results of our study help unveil the mechanisms by which pearl oysters respond adaptively to short-term hypoxia. • Pearl oysters are exposed to oxidative stress and apoptosis under short-term hypoxia. • Pearl oysters might adapt to short-term hypoxic treatment by increasing antioxidant activity. • Pearl oysters might adapt to short-term hypoxic stress by modulating immune activities. • Pearl oysters might adapt to short-term hypoxic treatment by maintaining protein homeostasis. • Pearl oysters might adapt to short-term hypoxic treatment by reorganizing the cytoskeleton. [ABSTRACT FROM AUTHOR]

Background: Few studies have reported that serum albumin (SA) levels on admission were associated with increased risk of long-term outcomes in patients with type B acute aortic dissection (AAD). The aim of this study was to investigate the effect of admission levels of SA on survival among patients with type B AAD undergoing endovascular therapy (EVT).Methods: A total of 131 patients with type B AAD undergoing EVT were retrospectively enrolled and followed up for 2.1years. They were divided into hypoalbuminemia and nonhypoalbuminemia groups. We analyzed the incidence of inhospital complications and long-term mortality. Kaplan-Meier curves and multivariable Cox regression analyses were used to investigate the associations between SA levels and survival.Results: Among 131 type B AAD patients, hypoalbuminemia was detected in 61 (46.6%) at admission. Compared to those without hypoalbuminemia, patients with hypoalbuminemia did not have higher inhospital complications; however, Kaplan-Meier analysis showed that they did have a significantly lower survival rate (73.8% vs 92.5%; log-rank χ(2)=9.8; P=.002). Multivariable Cox regression analysis further revealed that hypoalbuminemia was an independent predictor of long-term mortality among patients with type B AAD (hazard ratio, 4.28; 95% confidence interval, 1.36-13.47; P=.013), over 2.1years.Conclusions: Hypoalbuminemia is common in type B AAD patients and is independently associated with increased risk of long-term death. Renal dysfunction may be the main pathophysiological mechanism underlying hypoalbuminemia in patients with type B AAD. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are a class of non-coding RNA molecules with presumed post-transcriptional regulatory activity in various biological processes, such as development and biomineralization. Pinctada martensii is one of the main species cultured for marine pearl production in China and Japan. In our previous research, 258 pm-miRNAs had been identified by solexa deep sequencing in P. martensii , while it is far from the number of miRNAs found in other species. In this study, based on the transcriptome database of pearl sac, we identified 30 candidate pm-miRNAs by computational prediction. Among the obtained 30 pm-miRNAs, 13 pm-miRNAs were generated from the complementary strand of protein-coding mRNAs, and 17 pm-miRNAs could not be annotated using blastx and tblastn analysis. Notably, 10 of the 30 pm-miRNAs, such as pm-miR-1b, pm-miR-205b and pm-miR-375b, were homologous with the reported pm-miRNAs, respectively. To validate the existence of the identified pm-miRNAs, eight randomly selected pm-miRNAs were tested by stem loop quantitative RT-PCR analyses using 5.8S as the internal reference gene. Target prediction between the obtained pm-miRNAs and biomineralization-related genes by microTar, miRanda and RNA22 indicated pm-miR-2386 and pm-miR-13b may be the key factors in the regulation network by regulating the formation of organic matrix or the differentiation of mineralogenic cell during shell formation. Thus, this study enriched miRNA databases of pearl oyster and provided a new way to understand biomineralization. [ABSTRACT FROM AUTHOR]

• The novel MIPs were synthesized by using six different template molecules. • MIPs could adsorb PBDEs selectively in Triton X-100 simulated washing waste. • MIPs showed superior selective adsorption capacity of BDE-15 than activated carbon. • Van Der Waals interaction and hydrogen bond played major role in adsorption. • Molecular volume, planarity, and polarity of PBDEs mainly affected the adsorption. Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils. The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions. In this study, a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers (PBDEs) in soil washing effluent. The novel molecular imprinted polymers (MIPs) using different template molecules were synthesized by precipitation polymerization. Adsorption behaviors and mechanisms of MIPs were studied through experiments and theoretical calculations. The results show that 4-bromo-4′-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis. The maximal adsorption capacity of selected dummy molecular imprinted polymer (D 1 -MIP) was 1032.36 µmol/g, and that of part molecular imprinted polymer (P-MIP) was 981.13 µmol/g. Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88, the recovery percentage of Triton X-100 can reach 99.09%, confirming the feasibility of reusing surfactant. Various PBDEs could be removed by MIPs, and Quantitative Structure Property Relationship analysis revealed that PBDEs' molecular volume, planarity, polarity, and hydrophobicity have major influences on their adsorption performance. DFT calculation revealed that Van der Waals force and hydrogen bonding played important roles during selective adsorption. These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications. [Display omitted] [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) can efficiently regulate gene expression at intracellular and extracellular levels. Plant-derived miRNAs are highly enriched in animal haemolymph and regulate mammalian gene expression. However, evidence for food-derived miRNAs in Mollusca species is lacking. In this study, we fed the microalga Nannochloropsis oculata to the pearl oyster Pinctada fucata martensii and detected dietary miRNAs in exosomes isolated from the haemolymph by RNA-seq. In total, 273 endogenous miRNAs were identified in all biological replicates. We identified 23 microalgae-derived miRNAs in the exosomes of pearl oyster haemolymph. Most microalgae-derived miRNAs showed high expression levels in both exosomes and microalgae and exhibited apparent variation among individuals. These food-derived miRNAs were predicted to participate in endocytosis, apoptosis, signal transduction, energy metabolism, and biomineralization by targeting multiple genes. These findings demonstrated the cross-kingdom transport of miRNAs from microalgae to bivalves and provide insights into novel nutrient transmission through the food chain. [Display omitted] • Cross-kingdom miRNA transport from microalgae to bivalves by exosomes was detected. • Functions of circulating exosomal miRNAs in pearl oyster were examined. • Microalgae-derived miRNAs have multiple roles in pearl oyster. [ABSTRACT FROM AUTHOR]