| 1. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
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| 3. |
- Callaway, EM, et al.
(författare)
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A multimodal cell census and atlas of the mammalian primary motor cortex
- 2021
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 598:7879, s. 86-102
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Tidskriftsartikel (refereegranskat)abstract
- Here we report the generation of a multimodal cell census and atlas of the mammalian primary motor cortex as the initial product of the BRAIN Initiative Cell Census Network (BICCN). This was achieved by coordinated large-scale analyses of single-cell transcriptomes, chromatin accessibility, DNA methylomes, spatially resolved single-cell transcriptomes, morphological and electrophysiological properties and cellular resolution input–output mapping, integrated through cross-modal computational analysis. Our results advance the collective knowledge and understanding of brain cell-type organization1–5. First, our study reveals a unified molecular genetic landscape of cortical cell types that integrates their transcriptome, open chromatin and DNA methylation maps. Second, cross-species analysis achieves a consensus taxonomy of transcriptomic types and their hierarchical organization that is conserved from mouse to marmoset and human. Third, in situ single-cell transcriptomics provides a spatially resolved cell-type atlas of the motor cortex. Fourth, cross-modal analysis provides compelling evidence for the transcriptomic, epigenomic and gene regulatory basis of neuronal phenotypes such as their physiological and anatomical properties, demonstrating the biological validity and genomic underpinning of neuron types. We further present an extensive genetic toolset for targeting glutamatergic neuron types towards linking their molecular and developmental identity to their circuit function. Together, our results establish a unifying and mechanistic framework of neuronal cell-type organization that integrates multi-layered molecular genetic and spatial information with multi-faceted phenotypic properties.
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| 4. |
- Cao, Cejun, et al.
(författare)
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A novel multi-objective programming model of relief distribution for sustainable disaster supply chain in large-scale natural disasters
- 2018
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Ingår i: Journal of Cleaner Production. - : ELSEVIER SCI LTD. - 0959-6526 .- 1879-1786. ; 174, s. 1422-1435
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Tidskriftsartikel (refereegranskat)abstract
- To save lives and reduce suffering of victims, the focus of this paper is to design the strategies of relief distribution regarding beneficiary perspective on sustainability. This problem is formulated as a multi objective mixed-integer nonlinear programming model to maximize the lowest victims perceived satisfaction, and minimize respectively the largest deviation on victims perceived satisfaction for all demand points and sub-phases. Then, genetic algorithm is proposed to solve this mathematical model. To validate the proposed methodologies, a case study from Wenchuan earthquake is illustrated. Computational results demonstrate genetic algorithm here can achieve the trade-off between solution quality and computation time for relief distribution with the concern of sustainability. Furthermore, it indicates that the methodology provides the tools for decision-makers to optimize the structure of relief distribution network and inventory, as well as alleviate the suffering of victims. Increasingly, this paper expects to not only validate the proposed model and method, but also highlight the importance and urge of considering beneficiary perspective on sustainability into relief distribution problem. (C) 2017 Elsevier Ltd. All rights reserved.
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| 5. |
- GuangBo, Qu, et al.
(författare)
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Detection of tris-(2,3-dibromopropyl) isocyanurate as a neuronal toxicant in environmental samples using neuronal toxicity-directed analysis
- 2011
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Ingår i: Science in China Series B. - : Science Press. - 1674-7291 .- 1869-1870. ; 54:10, s. 1651-1658
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Tidskriftsartikel (refereegranskat)abstract
- Neuronal toxic pollutants in environment possess hazards to human health. It is essential to determine the causative neuronal toxicants in environmental samples. In the present study, viability of primary cultured cerebellar granule neurons (CGNs), combined with sample extraction, chemical fractionation and identification, was applied for screening acid-resistant neuronal toxic substances in environmental samples. River sediments and agricultural soils along the river near a brominated flame retardant (BFR) manufacturing plant in South China were collected to screen the key neuronal toxicants. The results indicated that the manufacturing plant was a source of neuronal toxicity risks. In the sediment and soil near the plant, one of the causative toxicants was identified as tris-(2,3-dibromopropyl) isocyanurate (TBC) using HPLC-MS/MS. In addition, an unknown chemical possibly causing significant neuronal toxicity was isolated from all the soil samples in the region.
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| 6. |
- Li, Congdong, et al.
(författare)
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Organizational coordination in sustainable humanitarian supply chain: an evolutionary game approach
- 2019
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526 .- 1879-1786. ; 219, s. 291-303
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Tidskriftsartikel (refereegranskat)abstract
- Sustainable humanitarian supply chain has a great impact on saving lives, decreasing human suffering and contributing to development. Organizational coordination plays an important role in it, although it is uncommon to be established due to the conflicting interests and expectations. To cope with the problem and achieve the sustainability of humanitarian supply chain, the coordination between private sector and humanitarian organization was further discussed with the help of sustainable principle regarding stakeholder approach. Different from the existing literature that elaborated the drivers and the advantages of coordination, this paper aims to explore the coordination mechanism regarding whether to coordinate, when to adopt the optimal coordinated strategy and how such a strategy can perform well. To analyze the tendency of the coordinated decisions, evolutionary game models concerning traditional and trust mechanisms were developed. Then, computational studies based on hypothetic data were simulated to validate the effectiveness of the proposed model. Results indicated that the coordination decision was affected by coordinated returns and costs, normal returns and extra returns in terms of the traditional mechanism. Several situations in regard to the coordinated decisions were analyzed by adopting evolutionary stable strategies. Moreover, trust had a significantly positive impact on coordination promotion under the support of potential returns and high-level trust. Finally, managerial insights for achieving the sustainable humanitarian supply chain were given from the perspective of organizational coordination and strategy.
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| 7. |
- Li, Lianhui, et al.
(författare)
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Sustainability Assessment of Intelligent Manufacturing Supported by Digital Twin
- 2020
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Ingår i: IEEE Access. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 2169-3536. ; 8, s. 174988-175008
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Tidskriftsartikel (refereegranskat)abstract
- As a major challenge and opportunity for traditional manufacturing, intelligent manufacturing is facing the needs of sustainable development in future. Sustainability assessment undoubtedly plays a pivotal role for future development of intelligent manufacturing. Aiming at this, the paper presents the digital twin driven information architecture of sustainability assessment oriented for dynamic evolution under the whole life cycle based on the classic digital twin mapping system. The sustainability assessment method segment of the architecture includes indicator system building, indicator value determination, indicator importance degree determination and intelligent manufacturing project assessing. A novel approach for treating the ambiguity of expert judgment in indicator value determination by introducing trapezoidal fuzzy number into analytic hierarchy process is proposed, while the complexity of the influence relationship among the indicators is processed by the integration of complex networks modeling and PROMETHEE II for the indicator importance degree determination. A two-stage evidence combination model based on evidence theory is built for intelligent manufacturing project assessing lastly. The presented digital-twin-driven information architecture and the sustainability assessment method is tested and validated on a study of sustainability assessment of 8 intelligent manufacturing projects of an air conditioning enterprise. The results of the presented method were validated by comparing them with the results of the fuzzy and rough extension of the PROMETHEE II, TOPSIS and VIKOR methods, indicator importance degree determining method by entropy and indicator value determining method by accurate expert scoring.
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| 8. |
- Nie, Duxian, et al.
(författare)
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Improved augmented Lagrangian coordination for optimizing supply chain configuration with multiple sharing elements in industrial cluster
- 2019
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Ingår i: Industrial management & data systems. - : EMERALD GROUP PUBLISHING LTD. - 0263-5577 .- 1758-5783. ; 119:4, s. 743-773
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Tidskriftsartikel (refereegranskat)abstract
- Purpose The purpose of this paper is to study various combination forms of the three basic sharing elements (i.e. orders sharing, manufacturers capacity sharing and suppliers capacity sharing) in the cluster supply chain (CSC), formulate a distributed model to protect enterprises decision privacy and seek to develop an effective method for solving the distributed complex model. Design/methodology/approach A distributed assembly cluster supply chain configuration (ACSCC) model is formulated. An improved augmented Lagrangian coordination (ALC) is proposed and used to solve the ACSCC model. A series of experiments are conducted to validate the improved ALC and the model. Findings Two major findings are obtained. First, the market orders quantity change and the sales price of the product have a great impact on both the optimal results of the ACSCC and the cooperative strategy, especially, when the market order increases sharply, enterprises have to adopt multiple cooperative strategies to complete the order; meanwhile, the lower sales price of the product helps independent suppliers to get more orders. Second, the efficiency and computational accuracy of the improved ALC method are validated as compared to the centralized ALC and Lingo11. Research limitations/implications This paper formulated the single-period ACSCC model under certain assumptions, yet a multi-period ACSCC model is to be developed, a more comprehensive investigation of the relationships among combination forms is to be extended further and a rigid proof of the improved ALC is necessary. Practical implications Enterprises in the industrial cluster should adopt different cooperative strategies in terms of the market orders quantity change and the sales price of the product. Social implications The proposed various combination forms of sharing elements and the formulated ACSCC model provide guidance to managers in the industrial cluster to choose the proper policy. Originality/value This research studies various combination forms of the three basic sharing elements in the CSC. A distributed ACSCC model has been established considering simultaneously multiple sharing elements. An improved ALC is presented and applied to the ACSCC problem.
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| 9. |
- Nie, Duxian, et al.
(författare)
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Optimizing supply chain configuration with low carbon emission
- 2020
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Ingår i: Journal of Cleaner Production. - : ELSEVIER SCI LTD. - 0959-6526 .- 1879-1786. ; 271
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Tidskriftsartikel (refereegranskat)abstract
- We study a new supply chain configuration problem to optimize the amount of carbon emission in the context of a service guarantee modelling framework, called supply chain configuration problem with low carbon emission (SCCP-LCE). A novel feature of our addressed problem is the explicit consideration of carbon emission cap and trading price in the supply chain configuration setting with operating capacity. The problem is formulated as a mixed-integer nonlinear programming (MINLP) model, and optimally solved by a custom designed dynamic programming algorithm. A case study and computational experiment are performed to examine the behaviour of optimal SCCP-LCE configurations, and the effects of key input parameters: carbon emission cap, trading price, and operating capacity. Our results suggest that government-imposed carbon emission policies, in terms of emission cap and trading price, have significant impacts and interactive effects on the optimal supply chain configuration and performance, including the safety stock cost and carbon emission cost. Our model and methodology offer a new analytical framework to prescribe data-driven decision support for both firms and governmental/environmental agencies to control carbon emission, while achieving optimal business and social benefits. (C) 2020 Elsevier Ltd. All rights reserved.
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| 10. |
- Qu, Guangbo, et al.
(författare)
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Identification of tetrabromobisphenol A diallyl ether as an emerging neurotoxicant in environmental samples by bioassay-directed fractionation and HPLC-APCI-MS/MS
- 2011
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 45:11, s. 5009-5016
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Tidskriftsartikel (refereegranskat)abstract
- Brominated flame retardants (BFRs) have been widely used as additives in products to reduce their flammability. Recent findings suggested that some BFRs exhibit neurotoxicity and thus might pose a threat to human health. In this work, a neurotoxicity assay-directed analysis was developed, combining sample cleanup, fractionation, chemical identification, and bioassay. Viability of primary cultured cerebellar granule neurons (CGNs) was used to evaluate the neurotoxicity of extracts or separated fractions from environmental samples. Tetrabromobisphenol A diallyl ether (TBBPA DAE) was identified as the causative toxicant in sediment samples collected from a river near a brominated flame retardant (BFR) manufacturing plant in South China. Liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI-MS/MS) was optimized to determine TBBPA DAE levels in the potent fractions and to confirm TBBPA DAE as the key neurotoxicant. On the basis of comparison with the structure of other TBBPA derivatives, the 1-propenyl group in TBBPA DAE appears to be the cause for the neurotoxic potency. The levels of TBBPA DAE in samples along the river were found at up to 49 ng/L for river water, 10,183 ng/g dry weight (dw) in surface sediments, and 42 ng/g dw in soils. According to the distribution of TBBPA DAE in the environmental samples, the manufacturing plant was identified as the release source of TBBPA DAE. To our knowledge, this study is the first to demonstrate potential neurotoxicity induced by TBBPA DAE in real environmental samples.
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| 11. |
- Ruan, Ting, et al.
(författare)
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Identification and evaluation of a novel heterocyclic brominated flame retardant tris(2,3-dibromopropyl) isocyanurate in environmental matrices near a manufacturing plant in southern China
- 2009
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 43:9, s. 3080-3086
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Tidskriftsartikel (refereegranskat)abstract
- A brominated flame retardant (BFR), hexabrominated heterocyclic tris-(2,3-dibromopropyl) isocyanurate (TBC), was identified,forthe first time, in the natural environment.The chemical was found in river water (2.33-163 ng/L), surface sediments (85.0 ng/g-6.03 microg/g dry weight (dw)), soils (19.6-672 ng/g dw), earthworm (9.75-78.8 ng/g dw), and carp samples (12.0-646 ng/g dw) from a factory-polluted area in southern China. It was found that TBC can strongly adsorb to organic material in sediment, and a trend of decreasing concentration with distance from the source in soil and earthworm samples, combined with calculated Kow (octanol-water partition coefficient) and Koa (octanol-air partition coefficient), suggests its potential ability to undergo regional transportation through dust deposition. Calculated results showed high Kow (log Kow = 7.37) and bioaccumulation factor (BAF) (log BAF = 4.30) of this BFR and indicate that TBC has semivolatile properties and bioaccumulation characteristic in certain biological species. Quantitative structure property relationships (QSPRs) modeling revealed that TBC has Koa (log Koa = 23.68) and Kaw (air-water partition coefficient) (log Kaw = -16.31) values several orders higher than those of other BFRs. The identification of this chemical additive further reminds us that the production and usage of heterocyclic BFRs may cause potential contamination to the surrounding environment
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| 12. |
- Ruan, Ting, et al.
(författare)
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Presence and partitioning behavior of polyfluorinated iodine alkanes in environmental matrices around a fluorochemical manufacturing plant : another possible source for perfluorinated carboxylic acids?
- 2010
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 44:15, s. 5755-5761
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Tidskriftsartikel (refereegranskat)abstract
- The indistinct origins of some ubiquitous perfluorinated alkyl acids have attracted great attention in recent decades. In this present work, even-chained polyfluorinated iodides (PFIs), a group of volatile perfluorinated compounds (PFCs), including four perfluorinated iodine alkanes (FIAs) and three polyfluorinated telomer iodides (FTIs) were confirmed to be present in the environment. A wide concentration range was found for FIAs at 1.41 to 3.08x104 pg/L, and for FTIs at 1.39 to 1.32x103 pg/L in the ambient air collected around a fluorochemical manufacturing plant in Shandong province, northern China. Whereas for surface soils, most of these PFIs were below detection limits and only small amounts of analytes with higher carbon chain (such as perfluorododecyl iodide and 1H,1H,2H,2H-perfluorodecyl iodide, 16.6-499 pg/g) could be sporadically detected. The presence of the PFIs in different environmental matrices in the investigated area and calculated vapor pressures (0.095-20.4 Torr) verify that they can be considered as volatile organic chemicals and easily be released into the atmosphere. Together with reported degradation ability and long-range transport potential, the identification of these PFIs indicates that unintentional release during the telomer reaction process might also be another route for the formation and distribution of certain polyfluorinated alcohols, aldehydes, and carboxylic acid derivatives under oxidative conditions in the environment.
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| 13. |
- Ruan, Ting, et al.
(författare)
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Trace determination of airborne polyfluorinated iodine alkanes using multisorbent thermal desorption/gas chromatography/high resolution mass spectrometry
- 2010
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Ingår i: Journal of Chromatography A. - : Elsevier. - 0021-9673 .- 1873-3778. ; 1217:26, s. 4439-4447
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Tidskriftsartikel (refereegranskat)abstract
- A novel gas chromatography/high resolution mass spectrometry method coupled with multisorbent thermal desorption cartridges has been developed for the determination of volatile neutral polyfluorinated iodine alkanes (PFIs) in airborne samples. It allows, for the first time, simultaneous analysis of four mono-iodized perfluorinated alkanes, three diiodized perfluorinated alkanes and four mono-iodized polyfluorinated telomers in ambient air samples. 3.75 L air sample was passed through a sorbent tube packed with 150 mg of Tenax TA and 200mg of Carbograph 1 TD for analyte adsorption. Important factors during the analysis procedures, such as safe sampling volume, air sampling rate, analyte desorption and transfer strategies, were optimized and good thermal desorption efficiencies were obtained. The method detection limit (MDL) concentration ranged from 0.04 pg/L for 1H,1H,2H,2H-perfluorododecyl iodide to 1.2 pg/L for perfluorohexyl iodide, and instrument response of a seven-point calibration was linear in the range of 10-1000 pg. Travel spike recoveries ranged from 83% to 116%. Small variabilities of less than 36% were obtained near the MDLs and the differences between triplicates were even smaller (2.1-7.3%) at 200 pg spiked level. The method was successfully applied to analyze ambient air samples collected near a point source, and five PFIs were identified (10.8-85.0 pg/L), with none of the analytes detectable at the background site.
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| 14. |
- Zhang, Abraham, et al.
(författare)
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Barriers to smart waste management for a circular economy in China
- 2019
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Ingår i: Journal of Cleaner Production. - : ELSEVIER SCI LTD. - 0959-6526 .- 1879-1786. ; 240
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Tidskriftsartikel (refereegranskat)abstract
- Waste management requires a new vision and drastic improvements for a transition to a zero-waste circular economy. In reality, however, many economies are producing more and more waste, which poses a serious challenge to environmental sustainability. The problem is enormously complex as it involves a variety of stakeholders, demands behavioral changes, and requires a complete rethinking of the current waste management systems and the dominant linear economic model. Smart enabling technologies can aid in a transformation of waste management toward a circular economy, but many barriers persist. This study first shortlists twelve important barriers to smart waste management in China based on interviews with experienced practitioners. It then prioritizes these barriers through a scientific prioritization technique, fuzzy Decision-Making Trial and Evaluation Laboratory (DEMATEL), based on the survey data from three representative stakeholders. It identified three key causal barriers: the lack of regulatory pressures, the lack of environmental education and culture of environmental protection, and the lack of market pressures and demands. Practical and theoretical implications were discussed based on the research results and findings. (C) 2019 Elsevier Ltd. All rights reserved.
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| 15. |
- Zhang, Kai, et al.
(författare)
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Digital twin-based opti-state control method for a synchronized production operation system
- 2020
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Ingår i: Robotics and Computer-Integrated Manufacturing. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0736-5845 .- 1879-2537. ; 63
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Tidskriftsartikel (refereegranskat)abstract
- The intelligent manufacturing strategy and customer demand have mutually promoted each other. Also, the production mode is shifting towards customized production, and more rental resources or services are introduced to the production system, therefore, the systems are becoming more complex. Compared with traditional production systems, such systems have some new features, this work calls this type of system as a synchronized production operation system (SPOS). Under such circumstances, production systems are influenced by more frequent uncertainties, and the planning-based production decision and control approach is no longer applicable. The opti-state control (OsC) method is proposed to help SPOS keep in an optimal state when uncertainties affect the system. Besides, a digital twin-based control framework (DTCF) is designed for getting the full element information needed for decision making. Based on the comprehensive information of the production system obtained by the DTCF, the OsC method is introduced to the virtual control layer to formulate the optimal target guiding the path of the system in real time through the dynamic matching mechanism (qualitative perspective). Then multi-stage synchronized control with analysis target cascading (ATC) method is used to get the local optimal state decisions (quantitative perspective). From both qualitative and quantitative aspects to ensure the system is under an optimal target path for optimal operation procedure. At last, a case study in a large-size paint making company in China is used to validate the effectiveness of the approach.
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| 16. |
- Zhang, Kai, et al.
(författare)
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IoT-enabled dynamic lean control mechanism for typical production systems
- 2019
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Ingår i: Journal of Ambient Intelligence and Humanized Computing. - : SPRINGER HEIDELBERG. - 1868-5137 .- 1868-5145. ; 10:3, s. 1009-1023
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Tidskriftsartikel (refereegranskat)abstract
- The emergence and subsequent popularization of lean has been one of the most significant developments in the history of operations management. However, there is a lack of systematic theory on the control framework underlying lean production. It is therefore difficult to conduct more in-depth research on Lean theory, specifically in the context of emerging technologies as smart manufacturing or Industry 4.0. In this study, process control theory is used to re-define several major lean methods and tools. Then a Lean-Oriented Optimum-State Control Theory (L-OSCT) is proposed that integrates these lean methods and tools into optimum-state control theory. On the level of method and mechanism, we adopt a recently emerged synchronization approach to obtain global-wide leanness of a large-scale system. L-OSCT provides dynamic process control in industrial networking systems. At last, a case study in a large-size paint making company in China is used to validate the effectiveness of the approach.
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| 17. |
- Zhang, Yingfeng, et al.
(författare)
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Analytical target cascading for optimal configuration of cloud manufacturing services
- 2017
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Ingår i: Journal of Cleaner Production. - : ELSEVIER SCI LTD. - 0959-6526 .- 1879-1786. ; 151, s. 330-343
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Tidskriftsartikel (refereegranskat)abstract
- Combining with advanced technologies (e.g., cloud computing, Internet of Things, and service-oriented technology), cloud manufacturing was proposed and gained wide attention. By managing a huge amount of distributed and idle manufacturing resources to meet various manufacturing requirements, cloud manufacturing provides sustainable means for promoting cleaner production. Manufacturing service configuration plays an important role in implementing cloud manufacturing. Most research adopted central optimization methods to get optimal service configuration results. However, these all-in-one methods with an individual decision model can hardly maintain the autonomous decision rights of different service providers. Consequently, service providers may lose their flexibility to achieve private decision objectives, which is unfavorable for keeping the sustainable competitive advantages of enterprises. In this paper, a decentralized decision mechanism named analytical target cascading is introduced to solve the manufacturing service configuration problem. An analytical target cascading model for the manufacturing service configuration problem is proposed based on the hierarchical structure of cloud manufacturing system. Elements in the proposed model are formulated and solved in a loose coupling and distributed manner. The situation when alternative service providers owned autonomous decision rights to configure their respective upstream manufacturing stages is also considered. A case study is employed to verify the effectiveness of analytical target cascading in solving the manufacturing service configuration problem. It shows that analytical target cascading can not only obtain the same manufacturing service configuration results as central optimization method but also maintain the autonomous decision rights of different service providers. (C) 2017 Elsevier Ltd. All rights reserved.
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| 18. |
- Zhu, Nali, et al.
(författare)
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Tris(2,3-dibromopropyl) isocyanurate, hexabromocyclododecanes, and polybrominated diphenyl ethers in mollusks from Chinese Bohai Sea.
- 2012
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Ingår i: Environmental Science and Technology. - Washington DC, USA : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:13, s. 7174-7181
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Tidskriftsartikel (refereegranskat)abstract
- A novel brominated flame retardant (BFR), tris(2,3-dibromopropyl) isocyanurate (TBC), as well as hexabromocyclododecanes (HBCDs) and polybrominated diphenyl ethers (PBDEs), were analyzed in 11 species of mollusks collected from nine coastal cities around the Chinese Bohai Sea in 2009 and 2010. The detection frequencies were 100%, 99%, and 77% for PBDEs, HBCDs, and TBC, respectively. Concentrations of ∑HBCDs ranged from below detection limit (nd) to 28.8 ng g(-1) on a dry weight (dw) basis, followed by ∑(12)PBDE (0.01-20.4 ng g(-1) dw) and TBC (nd-12.1 ng g(-1) dw). Statistically significant linear correlations were found among the three BFRs. Positive correlations were found between BFRs concentrations and lipid content in mollusks. The concentrations tend to decrease with increasing trophic levels of the mollusks, implying trophic dilution rather than biomagnifications of the BFRs in the aquatic food chains of the sampling area. Among the 11 mollusks species, Mytilus edulis showed higher bioaccumulation capability than others and was therefore considered to be an appropriate bioindicator of contamination by the BFRs in the Chinese Bohai Sea, in agreement with its previous selection for the biomonitoring of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). A dramatic decrease in PBDE concentrations in mollusks of the area was found for the time period from 2003 to 2010, with a half-life of only 2.3 ± 1.7 years, reflecting a rapid response of mollusks to the change in pollution of the marine environment.
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