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1.
Sci Total Environ ; 872: 162262, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36801337

RESUMO

In vitro assays are widely proposed as a test alternative to traditional in vivo standard acute and chronic toxicity tests. However, whether toxicity information derived from in vitro assays instead of in vivo tests could provide sufficient protection (e.g., 95 % of protection) for chemical risks remain evaluated. To investigate the feasibility of zebrafish (Danio rerio) cell-based in vitro test method as a test alternative, we comprehensively compared sensitivity differences among endpoints, among test methods (in vitro, FET and in vivo), and between zebrafish and rat (Rattus norvegicus), respectively using chemical toxicity distribution (CTD) approach. For each test method involved, sublethal endpoints were more sensitive than lethal endpoints for both zebrafish and rat, respectively. Biochemistry (zebrafish in vitro), development (zebrafish in vivo and FET), physiology (rat in vitro) and development (rat in vivo) were the most sensitive endpoints for each test method. Nonetheless, zebrafish FET test was the least sensitive one compared to its in vivo and in vitro tests for either lethal or sublethal responses. Comparatively, rat in vitro tests considering cell viability and physiology endpoints were more sensitive than rat in vivo test. Zebrafish was found to be more sensitive than rat regardless of in vivo or in vitro tests for each pairwise endpoint of concern. Those findings indicate that zebrafish in vitro test is a feasible test alternative to zebrafish in vivo and FET test and traditional mammalian test. It is suggesting that zebrafish in vitro test can be optimized by choosing more sensitive endpoints, such as biochemistry to provide sufficient protection for zebrafish in vivo test and to establish applications of zebrafish in vitro test in future risk assessment. Our findings are vital for evaluating and further application of in vitro toxicity toxicity information as an alternative for chemical hazard and risk assessment.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Ratos , Animais , Peixe-Zebra/fisiologia , Embrião não Mamífero , Testes de Toxicidade Crônica , Medição de Risco , Técnicas In Vitro , Mamíferos
2.
Sci Total Environ ; 828: 154569, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35302030

RESUMO

The increased use of neonicotinoid insecticides in aquatic environments poses a significant threat to non-target freshwater species. However, the existing water quality guidelines (WQGs) for neonicotinoids mainly focus on imidacloprid, and only a few authoritative institutions have established WQGs for other neonicotinoids. There is a critical need to develop WQGs and conduct ecological risk assessment (ERA) of different neonicotinoids in global freshwater environments. In this study, we derived interim acute and chronic guideline values and acute-to-chronic ratios (ACRs) for six neonicotinoids based on publicly available acute and chronic toxicity data. The exposure concentrations of neonicotinoids were obtained from published literature worldwide, and ERA was conducted for neonicotinoids in global freshwater ecosystems using a tiered approach. The derived chronic guideline values (95% confidence interval (CI), ng/L) were 0.63 (0.02-5.47) for thiacloprid (the lowest) and 16.4 for dinotefuran (the highest). The identified ACRs (95% CI) ranged from 90.9 (47.0-180) to 957 (102-3350), which can be used to extrapolate scarce chronic data from the acute data. Neonicotinoid concentrations in global freshwater were predicted from 10.6 (6.88-23.4) (thiacloprid) to 339 (211-786) ng/L (thiamethoxam). The estimated risk quotients ranged from 3.23 (dinotefuran) to 21.73 (thiacloprid), and the probability of exceeding WQGs ranged from 27.1% (dinotefuran) to 77.1% (thiacloprid). The ERA results indicated that the six neonicotinoids posed negligible acute risks but high chronic risks to global freshwater ecosystems, especially acetamiprid (65.8%) and thiacloprid (28.1%). The key findings of this study provide critical scientific information regarding the ecological risks of long-term neonicotinoid exposure and key insights for policy development and water quality control.


Assuntos
Inseticidas , Poluentes Químicos da Água , Ecossistema , Água Doce , Inseticidas/análise , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Medição de Risco , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água
3.
Mitochondrial DNA B Resour ; 6(10): 3044-3045, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595336

RESUMO

In this study, the complete mitochondrial genome of Plagiopholis styani was acquired and described. The mitogenome is a circular molecule of 19,669 base pairs (bp) in length including 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and two control regions (D-loop), which is similar to other Colubridae snakes. The total base composition of mitochondrial DNA is A 33.0%, C 24.9%, G 12.8%, and T 29.3%. The mitochondrial genome of Plagiopholis styani contributes to revealing the phylogenetic relationships among species of the Colubridae family.

4.
ACS Appl Mater Interfaces ; 12(1): 627-636, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31820917

RESUMO

Lithium metals fit the growing demand of high-energy density rechargeable batteries because of their high specific capacity and low redox potential. However, the lithium-metal anodes are abandoned because of various defects. In this study, we apply composite plating into the protection of lithium-metal anodes. We confirmed that the Mg3N2 nanoparticle dispersed in the ether electrolyte can be easily composite-plated with lithium, resulting in a flat, dense, and dendrite-free lithium deposition layer during the electrodeposition process. In addition, the Mg3N2 plated in the lithium metal phase would react with lithium and then generate a Li3N-rich solid electrolyte interphase (SEI) layer, mitigating continuous side reactions of the electrolyte on the Li metal. In addition, another product of the reaction is Mg which can work as lithiophilic sites in electrodeposition. The combined effect of the two fields can effectively improve the performance of lithium metal anodes. The Li3N-rich SEI layer would grow well on the surface of the three-dimensional (3D) lithium anode by composite plating. Furthermore, composite plating with the Mg3N2-containing electrolyte is a viable route that can be used for various 3D current collectors easily with a small volume effect. Here, we show that the composite plating 3D lithium metal anode is successfully applied in the Li-S battery with a long lifetime.

5.
ACS Appl Mater Interfaces ; 11(34): 30902-30910, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31380616

RESUMO

Metallic lithium (Li), with its high capacity and low redox potential, shows significant development potential for high-energy-density Li batteries. Unfortunately, huge volumetric changes, uncontrollable Li dendrites, and interfacial parasitic reactions limit its commercial application. Herein, we demonstrate a rational strategy of encapsulating metallic Li into the interior spaces of hollow carbon (C) nanocages for dendrite-free Li metal anodes. We find that the poly(vinylidene difluoride)-binder-modified thin-layer C walls on the C nanocages can guide Li deposition into the interior spaces of these hollow C nanocages and simultaneously reduce the interfacial parasitic reactions between deposited Li metal and an electrolyte. In addition, because of the high specific surface area and huge interior spaces of the C nanocages, the local current density can be reduced and large volume changes are mitigated. Specifically, this electrode exhibits negligible volume changes at 1.0 mAh/cm2 and a 14.9% volume change at 3.0 mAh/cm2. The copper (Cu) foil electrode exhibits 87.9% and 234.3% volume changes at the corresponding deposition capacities. Consequently, a C-nanocage-modified electrode exhibits an outstanding Coulombic efficiency of 99.7% for nearly 150 cycles at a current density of 1.0 mA/cm2, while a Cu foil electrode exhibits less than a 70.0% Coulombic efficiency after only 43 cycles. When paired with a sulfur cathode, the C-nanocage-modified electrode exhibits better cycling and rate performances than the pristine Cu foil electrode.

6.
Mitochondrial DNA B Resour ; 5(1): 300-301, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33366529

RESUMO

In this study, the complete mitochondrial genome of Rhacophorus omeimontis was obtained and described. The sequenced mitogenome is total 19,604 base pairs (bp) in length, which contained 13 protein-coding genes (PCGS), 22 transfer RNA genes (tRNA), 2 ribosomal RNA genes (rRNA), and 2 control regions (D-loop). The overall base composition of the mitochondrial DNA is 32.5% for A, 30.5% for T, 23.3% for C, and 13.7% for G, and the percentage of GC content is 37.0%. The complete mitochondrial genome information of R. omeimontis will contribute to revealing the phylogenetic relationships among species of family Rhacophoridae.

7.
ACS Appl Mater Interfaces ; 10(22): 18709-18716, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29749725

RESUMO

To evade the hurdles of dendrite growth and low Coulombic efficiency resulting from lithium metal anodes, integrating lithiated silicon anodes with sulfur cathodes to configure a lithiated silicon-sulfur (Si-S) full cell is a promising strategy to develop high-energy and high-safety rechargeable lithium batteries. Nevertheless, Si-S full cells always suffer accelerated capacity decay, even when excellent electrochemical performance of Li-S and Li-Si half cells is achieved. Herein, we report a comprehensive investigation of the capacity fade mechanism of Si-S full cells. It is revealed that cyclable lithium loss plays a key role in the accelerated capacity fade of Si-S full cells. In addition, cyclable lithium loss in Si-S full cells is mainly divided into irreversible lithium loss by forming inactive lithium compounds due to polysulfide shuttling and other side reactions, and restricted lithium because the Si/C anode cannot be fully delithiated when the Si-S full cell reaches the discharge cutoff voltage. From the 1st cycle to the 100th cycle, the irreversible lithium loss is determined to have increased from 21.7 to 54.5%, whereas the restricted lithium decreased from 24.6 to 16.7%, respectively. The high specific surface area of a Si/C anode leads to a remarkable irreversible lithium loss due to serious polysulfide shuttling in Si-S full cells. This work will help advance the practical application of Li-S batteries.

8.
Molecules ; 21(5)2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27136511

RESUMO

A flower-like nanobioreactor was prepared for resolution of ibuprofen in organic solvents. Ultrasound irradiation has been used to improve the enzyme performance of APE1547 (a thermophilic esterase from the archaeon Aeropyrum pernix K1) in the enantioselective esterification. Under optimum reaction conditions (ultrasound power, 225 W; temperature, 45 °C; water activity, 0.21), the immobilized APE1547 showed an excellent catalytic performance (enzyme activity, 13.26 µmol/h/mg; E value, 147.1). After ten repeated reaction batches, the nanobioreactor retained almost 100% of its initial enzyme activity and enantioselectivity. These results indicated that the combination of the immobilization method and ultrasound irradiation can enhance the enzyme performance dramatically.


Assuntos
Esterases/metabolismo , Ibuprofeno/química , Aeropyrum/enzimologia , Reatores Biológicos , Enzimas Imobilizadas , Esterificação , Ondas de Choque de Alta Energia
9.
J Colloid Interface Sci ; 251(1): 120-4, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16290709

RESUMO

The surfactant-encapsulated cluster (SEC) composed of a hydrophobic dimethyl dioctadecyl ammonium (DODA) shell and an encapsulated hydrophilic polyoxoanion core can form casting films. The structure of the casting film is influenced by evaporation rates of organic solvent. When the casting films are prepared by slow evaporation of chloroform, the alkyl chains are considered to possess a partial interdigitation, and the interdigitated length is 1.6 nm. The casting film structure is characterized by scanning force microscopy (SFM), Fourier transformation infrared (FT-IR), wide-angle X-ray diffraction, and differential scanning calorimetry (DSC).

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