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1.
Nutrients ; 13(4)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810496

RESUMO

(1) Background: Labeling is one of the significant strategies to guide sustainable consumption behaviors. Nowadays, multi labels being displayed on the front-of-pack of food products is a common phenomenon. However, labels seldom operate solo, and competition or complement effects may be exerted on different labels. Therefore, the research objective is to explore the interaction effect when nutrition and low-carbon labels appear simultaneously; (2) Methods: Across four scenario-based experiments, including ice cream, yogurt, steak, and toast, this study manipulated the separate and joint occurrences of low-carbon and nutrition labels, the interaction effect of joint labels was tested, and the serial mediation model, which includes resource allocation and anticipated enjoyment of food consumption, was verified; (3) Results: Results show that people have a positive preference for the nutrition label and the carbon label, respectively, while these two labels working simultaneously attenuate the positive effect of the single label. When facing nutrition and carbon labels simultaneously, people would infer partial resources are allocated to healthy and environmental aspects so they have a lower anticipated enjoyment from food consumption. Thus, these two labels working simultaneously attenuate the positive effect of the single label, and consumers have a lower evaluation of food products. In addition, the joint backfire on the effect is only exerted on people with a higher level of zero-sum bias and only when joint labels have a high consistency of labels; (4) Conclusions: This study solved the contradictory problem of the joint effect of positive labels. The findings in this research contribute to promote sustainable food consumption. We suggest that similar labels should be avoided in the same front-of-pack of food, and manufacturers need to use ads to bring down consumers' zero-sum bias.

2.
Mar Pollut Bull ; 165: 112130, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33582421

RESUMO

Microplastics (MPs) in sediment environments have been widely reported. As the number of samples increases, establishing a reliable and effective method becomes increasingly urgent for the rapid extraction and identification of MPs in sediments. Herein, we proposed a system with continuous density flotation of NaBr-ZnCl2 (mixture of NaBr and ZnCl2) solution for extracting MPs in a sediment sample, combined with micro-Fourier transform infrared (µ-FT-IR) imaging scanning for identification of MPs. The recoveries of MPs were estimated for four different sizes, shapes, and ten different types of polymers. The results indicated NaBr-ZnCl2 solution showed a high recovery rate from 88.33% to 100.00% for extracting these different MPs. The µ-FT-IR imaging scanning allows for the detection of plastic down to the size of 6.25 µm in filed samples, and merely takes about 3 min, which was validated by testing of sediments from Jiaozhou Bay, China and its adjacent estuaries.


Assuntos
Microplásticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
3.
PLoS One ; 16(2): e0247279, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33617582

RESUMO

As an important transportation, the belt conveyor has been widely used and researched. It is urgent to solve the problem of energy saving and consumption reduction of belt conveyor. Aiming at reducing high energy consumption in the rated-speed operation of a belt conveyor, the present paper establishes an energy-saving belt-speed model of a belt conveyor using a polynomial regression-fitting algorithm and a small number of sample observations, and proposes a speed regulation strategy and particle swarm optimization-proportional-integral-derivative algorithm for the variable-belt-speed energy-saving control of a belt conveyor based on the material flow rate. The control strategy and algorithm adjust the running speed of the belt conveyor accurately according to changes in the material flow rate, thus reducing damage of frequent speed regulation to the belt conveyor and saving energy. Simulation analysis of a practical case shows that energy-saving belt-speed model, speed regulation strategy, and algorithm effectively reduce the energy consumption of a belt conveyor, and they thus have high application value in coal, ports, power, mine, metallurgy, chemical, and other industries. Further work in this field can be focused on the prediction of material flow rate of belt conveyor, the controllable adjustment duration of algorithm and the reduction of overshoot.

4.
Sci Rep ; 11(1): 411, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432082

RESUMO

The intriguing multi-scale fractal patterns ubiquitously observed in nature similarly emerge as fascinating structures in two-phase fluid flows of bio-oil breakup and atomization processes. High-resolution microscopy of the two-phase flows under 15 flow conditions (cases of different flow rates of the liquid and co-flowing air streams as well as different degrees of liquid preheating) reveal that the geometrical complexities evolve under the competing/combined action of the instability mechanisms such as Kelvin-Helmholtz, Rayleigh-Taylor and Rayleigh-Plateau leading into the transition from break-up to atomization. A thorough analysis of the higher order moments of statistics evaluated based on the probability density functions from 15,000 fractal dimension samples suggest that a single-value analysis is not sufficient to describe the complex reshaping mechanisms in two-phase flows. Consistently positive skewness of the statistics reveal the role of abrupt two-phase mechanisms such as liquid column rupture, ligament disintegration, liquid sheet bursting and droplet distortions in a hierarchical geometrical entanglement. Further, large kurtosis values at increased flow inertia are found associated with turbulence-induced intermittent geometrical reshaping. Interestingly, the proposed power-law correlation reveals that the global droplet size obtained from laser-diffraction measurements declines as the two-phase geometrical complexity increases.

5.
Bioresour Technol ; 319: 124117, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32979594

RESUMO

Azo dyes pose hazards to ecosystems and human health and the cosubstrate strategy has become the focus for the bioremediation of azo dyes. Herein, Brilliant Crocein (BC), a model pollutant, was biodegraded by Providencia rettgeri domesticated from activated sludge. Additional ethanol, as a cosubstrate, could accelerate P. rettgeri growth and BC biodegradation, as reflected by the Gompertz models. This phenomenon was attributed to the smaller metabolites and greater number of potential pathways observed under the synergistic effect of ethanol. Genomic analysis of P. rettgeri showed that functional genes related to azo bond cleavage, redox reactions, ring opening and hydrolysis played crucial roles in azo dye biodegradation. Furthermore, the mechanism proposed was that ethanol might stimulate the production of additional reducing power via the expression of related genes, leading to the cleavage of azo bonds and aromatic rings. However, biodegradation without ethanol could only partly cleave the azo bonds.


Assuntos
Etanol , Providencia , Compostos Azo , Biodegradação Ambiental , Corantes , Ecossistema , Genômica , Humanos , Cinética , Providencia/genética
6.
Mol Med Rep ; 23(1): 1, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33179099

RESUMO

Acute myocardial infarction (AMI) is a common cardiac disease. Long non­coding RNA maternally expressed 3 (MEG3) is associated with cellular processes in numerous complicated diseases, including AMI. However, the mechanism underlying MEG3 in myocardial hypoxia is not completely understood. The present study aimed to investigate the underlying mechanism of MEG3 in myocardial hypoxia. The expression levels of hypoxia­inducible factor 1α (HIF1α), MEG3, microRNA (miR)­325­3p, and transient receptor potential cation channel subfamily V member 4 (TRPV4) in hypoxia­treated H9c2 cells were detected via reverse transcription­quantitative PCR. The protein expression levels of HIF1α, Bcl­2, Bax, cleaved caspase­3 and TRPV4 were detected via western blotting. Cell viability and apoptosis were assessed by performing an MTT assay and flow cytometry, respectively. Lactate dehydrogenase (LDH) release was monitored by conducting an LDH determination assay. The dual­luciferase reporter assay was performed to verify the targeted relationship between miR­325­3p and MEG3 or TRPV4. The expression levels of MEG3 and TRPV4 were significantly increased, whereas miR­325­3p expression levels were significantly decreased in hypoxic H9c2 cells compared with normoxic H9c2 cells. In addition, miR­325­3p was downregulated by MEG3 compared with the vector group, and miR­325­3p targeted TRPV4 in hypoxia­treated H9c2 cells. The results indicated that MEG3 knockdown attenuated hypoxia­stimulated injury in H9c2 cells by regulating miR­325­3p. TRPV4 knockdown also mitigated hypoxia­induced injury in H9c2 cells via miR­325­3p. Furthermore, compared with the vector group, MEG3 increased TRPV4 expression in hypoxia­treated H9c2 cells by sponging miR­325­3p. Collectively, the results of the present study suggested that MEG3 modulated TRPV4 expression to aggravate hypoxia­induced injury in rat cardiomyocytes by sponging miR­325­3p.

7.
Ecotoxicol Environ Saf ; 204: 111067, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32745786

RESUMO

The impacts of microplastics (MPs) and phthalates (PAEs), a class of MP-associated contaminants, on the marine environment are not thoroughly understood despite concern over their adverse effects on humans and ecosystems. Field studies linking MPs and PAEs in seawater have not yet been reported. We investigate for the first time the correlation between MPs contamination and the presence of PAEs in the surface seawater of Jiaozhou Bay (JZB), a semi-enclosed metropolitan bay in northern China heavily impacted by human activity. The abundance of MPs, dominated by polyethylene and polyethylene terephthalate mostly smaller than 2 mm, ranged between 24.44 items/m3 and 180.23 items/m3, with the majority being black and transparent fibers and fragments. Concentrations of PAEs varied from 129.96 ng/L to 921.22 ng/L. Relatively higher abundances of MPs and higher concentrations of PAEs were generally found in areas near riverine inputs and sewage treatment plants. There was a strong correlation between PAEs concentration and MPs abundance, suggesting that they are closely linked. In a risk assessment combining PAEs and MPs, the risk quotients (RQs) indicated that the ecological risk of di-n-butyl phthalate in JZB was relatively high (0.046

Assuntos
Baías/química , Monitoramento Ambiental/métodos , Microplásticos/análise , Ácidos Ftálicos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , China , Dibutilftalato/análise , Ecossistema , Humanos , Polietileno/análise
8.
Oncol Lett ; 19(6): 3761-3774, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32391094

RESUMO

The present study aimed to investigate the association between surgical methods and survival outcomes in patients with astrocytoma. Patients diagnosed with astrocytoma between January 2004 and December 2015 were identified using the Surveillance, Epidemiology and End Results database. Kaplan-Meier curves and Cox regression were used to analyze the effects of surgical methods on overall survival (OS) and cancer-specific survival (CSS). Among 42,224 eligible patients with astrocytoma, 11,427 (27.1%) patients did not receive surgery, 7,661 (18.1%) received excisional biopsy (EB), 5,520 (13.1%) received a subtotal resection (STR), 6,037 (14.3%) received a gross resection (GR), 5,314 (12.6%) received a partial resection (PR) and 6,265 (14.8%) received a gross total resection (GTR). Patients who underwent GR had the longest survival time (17.00 months). However, over time, the proportion of patients who underwent STR or GR increased, whereas the proportion of patients who did not undergo surgery, PR or GTR decreased. Furthermore, surgical method was an independent prognostic factor for OS and CSS for the patients with astrocytoma. Multivariate Cox regression showed that GTR was associated with the more favorable OS [hazard ratio (HR), 0.80; 95% confidence interval (CI), 0.77-0.83; P<0.001] and CSS (HR, 0.80; 95% CI, 0.77-0.83; P<0.001) times compared with EB. Moreover, similar results were observed in subgroup analyses based on summary stage and grade. In the present study, it was demonstrated that GTR was one of the effective surgical methods for improved OS and CSS time in patients with astrocytoma. However, among the American astrocytoma population, the proportion of patients who underwent GTR decreased. It is necessary to further advocate for the efficacy of GTR.

9.
PLoS One ; 15(1): e0227992, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31990921

RESUMO

Aiming at solving the problem of high energy consumption in the rated belt speed operation of a belt conveyor system when the material flow rate is reduced, the power consumption of the frequency converter, motor, and belt conveyor is analyzed, a power consumption model of the belt conveyor system is established, the relationship between the power consumption of the belt conveyor system and belt speed is obtained, and a energy-saving control strategy of the belt conveyor with variable belt speed based on the material flow rate is put forward. The energy consumption of the belt conveyor is analyzed for a practical case. Results show that the power consumption model is accurate and the control strategy effectively reduces energy consumption. The model has high application value in coal, ports, power, mine, metallurgy, chemical, and other industries.


Assuntos
Automação/instrumentação , Indústria Manufatureira/instrumentação , Automação/economia , Eletricidade , Humanos , Cinética , Indústria Manufatureira/economia , Indústria Manufatureira/métodos
10.
Sci Total Environ ; 706: 135699, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31940724

RESUMO

Transport of terrigenous organic matter (TerOM) in marginal seas plays an important role in marine carbon cycle which is closely related to global climate change. Suspended particulates in East China Sea (ECS) inner shelf are subject to strong influence of seasonally varied Zhe-Min Coastal Current (ZMCC) and Taiwan Warm Current (TWC). Transport of TerOM attached to the mineral particulates is therefore largely dependent on these hydrodynamic conditions. To address the transport pattern of TerOM in highly dynamic marginal seas and its implication, sediment samples were collected from ECS inner shelf and fractionated by water elutriation to simulate the hydrodynamic sorting process. Lignin phenols were determined for each fraction. The abundance of C phenols preferentially concentrated in the finer fractions, which is believed as a collective effect of hydrodynamic sorting, diagenetic reactivity and association preference of C phenols with finer sediments. In contrast to the expectation, sediments at the southernmost site did not have the highest mass percentage for the finest fraction, the lowest lignin abundance and the highest degradation status. Combining the results of lignin parameters with seawater temperature and salinity profiles, it is proposed that sediments are transported along the inner shelf southward in winter and northward in summer to some extent with the influence of seasonally varied ZMCC and TWC, induced by the seasonality of East Asia Monsoon (EAM). Finer grained sediments are more susceptible to this process. This transport pattern, which was only reported previously in ocean modeling, was firstly supported by the observation of lignin biomarkers. It is suggested that cross-shelf transport of sediments in ECS seems to be possible, but is complicated and is also affected by the seasonal variation of EAM. This study improved the understanding of hydrodynamic sorting on the transport of TerOM and carbon cycling in the marine system.

11.
Biomed Eng Online ; 18(1): 71, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164131

RESUMO

BACKGROUND: Patients with end-stage heart failure must receive treatment to recover cardiac function, and the current primary therapy, heart transplantation, is plagued by the limited supply of donor hearts. Bioengineered artificial hearts generated by seeding of cells on decellularized scaffolds have been suggested as an alternative source for transplantation. This study aimed to develop a tissue-engineered heart with lower immunogenicity and functional similarity to a physiological heart that can be used for heart transplantation. MATERIALS AND METHODS: We used sodium dodecyl sulfate (SDS) to decellularize cardiac tissue to obtain a decellularized scaffold. Mesenchymal stem cells (MSCs) were isolated from rat bone marrow and identified by flow cytometric labeling of their surface markers. At the same time, the multi-directional differentiation of MSCs was analyzed. The MSCs, endothelial cells, and cardiomyocytes were allowed to adhere to the decellularized scaffold during perfusion, and the function of tissue-engineered heart was analyzed by immunohistochemistry and electrocardiogram. RESULTS: MSCs, isolated from rats differentiated into cardiomyocytes, were seeded along with primary rat cardiomyocytes and endothelial cells onto decellularized rat heart scaffolds. We first confirmed the pluripotency of the MSCs, performed immunostaining against cardiac markers expressed by MSC-derived cardiomyocytes, and completed surface antigen profiling of MSC-derived endothelial cells. After cell seeding and culture, we analyzed the performance of the bioartificial heart by electrocardiography but found that the bioartificial heart exhibited abnormal electrical activity. The results indicated that the tissue-engineered heart lacked some cells necessary for the conduction of electrical current, causing deficient conduction function compared to the normal heart. CONCLUSION: Our study suggests that MSCs derived from rats may be useful in the generation of a bioartificial heart, although technical challenges remain with regard to generating a fully functional bioartificial heart.


Assuntos
Bioengenharia , Coração Artificial , Células-Tronco Mesenquimais/citologia , Tecidos Suporte , Animais , Diferenciação Celular , Células Endoteliais/citologia , Masculino , Miócitos Cardíacos/citologia , Ratos
12.
Sci Rep ; 9(1): 6784, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043684

RESUMO

Microscopic imaging as well as the particle image velocimetry (PIV) are carried out to evaluate the concentration, velocity and vorticity fields near the contact line of the nano-particles-laden evaporating sessile droplets. After the onset of the linear thermocapillary instabilities due to the Marangoni perturbations, the non-linear state sets in and the micro-scale jet-like vortex structures are ejected from the contact line towards the center of the droplet. Afterwards, the jet-like vortical structures expand in the spanwise directions and start to interact with the neighbouring structures. Two types of the inverse cascade mechanisms are found to occur. In the first kind, the vortices of the similar length scale merge and continuously produce larger vortices and corresponding wavelength growth. The second inverse cascade mechanism takes place due to the entrainment of the smaller vortices into the larger structures. Both inverse cascade processes are identified as the continuous feeding of the kinetic energy from the smaller scales to the larger scales. For individual micro-jets the velocity field characterizes the jet-like vortex structures ejected from the contact line towards the droplet center opposing the bulk flow from the center towards the contact line. In addition, the vorticity field overlaid by the velocity streamlines identify the sense of rotation of the low pressure zones on either side of the micro-jet as well as the high pressure stagnation point at the tip.

13.
Ecotoxicol Environ Saf ; 179: 111-118, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31030054

RESUMO

Surface sediment samples (n = 92) were collected from Hangzhou Bay to investigate the transport and deposition of polybrominated diphenyl ethers (PBDEs) and to assess the ecological risks in Hangzhou Bay. The concentrations of ∑7PBDEs (sum of BDE-28, 47, 99, 100, 153, 154, 183) and BDE-209 ranged from 3.61 to 91.09 pg g-1 and from non-detectable to 2007.52 pg g-1 (dry weight), respectively. The high values of ∑7PBDEs and BDE-209 were commonly occurred at the northeast of Hangzhou Bay and the Nanhui Spit coast of Shanghai. Compared with the south part of the bay, the dominance of BDE-209 was more prominent and the linear correlations between PBDEs concentrations and TOCs as well as median grain size were more significant in the northern Hangzhou Bay. Hydrodynamic forcing on the transport and deposition of PBDEs is primarily responsible for the discrepancy of this spatial distribution in these two parts. In addition to BDE-209, BDEs-153, 99, 47, and 100 were also the abundant congeners. Three principal components were extracted using principal component analysis (PCA), mainly attributed to human activities, erosion of polluted soils via surface runoff and release from products for PC1, PC2 and PC3, respectively. The calculation results of mass inventories, hazard quotients (HQs) and risk quotients (RQs) indicated that the ecological risk of PBDEs in Hangzhou Bay was low. The multiple effect of hydrodynamic forcing with complicated and large-scope tidal currents made it hard to deposit for organic matters and contaminants in Hangzhou Bay.


Assuntos
Baías/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Éteres Difenil Halogenados/análise , Poluentes Químicos da Água/análise , China , Humanos , Hidrodinâmica , Bifenil Polibromatos/análise , Medição de Risco
14.
Environ Pollut ; 247: 80-88, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30665190

RESUMO

As a developed city in North China, Tsingtao is believed to be suffering from the pollution of polybrominated diphenyl ethers (PBDEs) due to the rapid industrialization and urbanization in recent years. In this work, 8 PBDE congeners were detected in sediments from Moshui River, Tsingtao. BDE-209 and sum of 7 low brominated PBDE congeners (∑7PBDEs, excluding BDE-209) ranged from 10.2 × 10-3 to 237 × 10-3 mg kg-1 and from 1.62 × 10-3 to 23.1 × 10-3 mg kg-1 d.w., respectively. PBDE concentrations decreased in the order of midstream > downstream > upstream, attributing to the discrepancies in anthropogenic activities among these areas. Principal component analysis coupled with multiple linear regression (PCA-MLR) revealed that 24.4% of PBDEs were derived from surface runoff of contaminated soils, 58.2% from direct discharge of local sources and 17.4% from atmospheric deposition. The probabilistic health risk assessment of PBDEs was performed by using Monte Carlo simulation. The carcinogenic and non-carcinogenic risks based on total PBDEs were low for children and teens, whilst severe for adults. However, based on bioaccessible PBDEs (in vitro gastrointestinal model), there was no obvious health risk for the three age groups. To the best of our knowledge, the present study was the first attempt to assess the health risk by using bioaccessible PBDEs in sediments.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Éteres Difenil Halogenados/análise , Rios/química , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Adolescente , Adulto , Criança , China , Monitoramento Ambiental , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Humanos , Desenvolvimento Industrial , Medição de Risco , Urbanização
15.
J Hazard Mater ; 359: 203-212, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30036750

RESUMO

Nonylphenols (NPs) are known as Endocrine Disputing Chemicals (ECDs) and Persistent Organic Pollutants (POPs) and have attracted continuous attention. Biodegradation is one of the effective ways for pollutant removal in aquatic, sedimentary and soil environments. In this study, two estuarine derived fungi strains, NPF2 and NPF3, were screened from Moshui river estuarine sediment and identified as genus Aspergillus. The growth curves of the two strains as well as the removal and degradation rates for 4-n-NP in Potato Dextrose(PD)medium were used to evaluate their degradation ability. Both strains showed high efficiency for 4-n-NP degradation with 86.03% and 98.76% removal rates in 3 days for NPF2 and NPF3, respectively. Determination of degradation intermediates by LC-MS suggested that the mechanisms for 4-n-NP biodegradation by NPF2 and NPF3 are quite different. Some key functional genes for the two strains also provided supplementary evidences for the different biodegradation mechanism. On strain NPF2, with participation of Cox1, 2 and 3, 4-n-NP degradation starts from reaction at the terminal of the long alkyl chain. The chain reduces one carbon atom once within a cycle of hydroxylation, subsequent oxidation at α-C position and decarboxylation. However, on NPF3, with involvement of sMO, Cel7A, Cel7B and ATEG-00639, 4-n-NP degradation starts from benzene ring, converting into fatty acids. The latter bio-pathway was the first time reported for NPs degradation on fungi.


Assuntos
Aspergillus/metabolismo , Fenóis/metabolismo , Poluentes Químicos da Água/metabolismo , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Biodegradação Ambiental , Estuários , Genes Fúngicos , Sedimentos Geológicos/microbiologia
16.
Chemosphere ; 189: 104-114, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28934650

RESUMO

The Southern Yellow Sea (SYS) is an important reservoir of anthropogenic organic contaminants, such as polybrominated diphenyl ethers (PBDEs). To reconstruct the historical records of PBDEs and examine their relationships with the human activities and organic matters, a210Pb-dated sediment core was collected from the central mud area in the SYS. The concentrations of tri-to hepta-BDEs (∑7PBDEs) and BDE-209 ranged from 9.8 to 99.8 pg g-1 d.w. and from 12.1 to 855.4 pg g-1 d.w., respectively, both displaying the increasing trends from the bottom to the surface. More importantly, there was a faster increase for PBDEs since the 1990s, especially for BDE-209, which responded well with the rapid economic growth, and the increases of urbanization and industrialization in the local areas of the SYS. The analogously vertical patterns and significant relationships between PBDEs and total organic carbon (TOC) implied the TOC-dependent deposition of PBDEs in the core. Furthermore, multiple biomarker-based proxies of terrestrial organic matter (TOM) and marine organic matter (MOM) were introduced to systematically investigate the different effects of TOM and MOM on PBDE deposition in the SYS. The similarly down-core profiles and significant correlations were found between PBDEs and the MOM proxies (sum of rassicasterol, dinosterol and C37 alkenones (∑A + B + D) and marine TOC) as well as the branched and isoprenoid tetraether (BIT), but not for TOM proxies (∑C27+C29+C31n-alkanes, terrestrial and marine biomarker ratio (TMBR) and terrestrial TOC), indicating that MOM was an important factor driving PBDE deposition in the sediment core from the SYS.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Éteres Difenil Halogenados/análise , China , Atividades Humanas/tendências , Humanos , Desenvolvimento Industrial/tendências , Água do Mar , Urbanização/tendências , Poluentes Químicos da Água/análise
17.
Xenotransplantation ; 24(6)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28833558

RESUMO

Xenotransplantation is an effective way to solve the problem of donor shortage in clinical transplantation. However, clinical use of xenotransplantation is currently limited due to immunological challenges such as acute vascular rejection and cell-mediated rejection. To finally surpass this immunological barrier, more preclinical research is needed into the molecular mechanisms of rejection and the possible effects of new immunosuppressants. Our aim was to create a refined, highly reproducible protocol to establish the most suitable rat-to-mouse heterotopic heart transplantation model using the cuff technique.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/imunologia , Transplante de Coração , Animais , Modelos Animais de Doenças , Rejeição de Enxerto/imunologia , Transplante de Coração/métodos , Xenoenxertos , Imunossupressores/farmacologia , Camundongos , Ratos , Transplante Heterólogo/métodos , Transplante Heterotópico/métodos
18.
Environ Pollut ; 230: 153-162, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28651087

RESUMO

As an emerging halogenated organic contaminant, Dechlorane Plus (DP) was scarcely reported in marine environments, especially in China. In this work, 35 surface sediments and a sediment core were collected across the Southern Yellow Sea (SYS) to comprehensively explore the spatio-temporal distribution and possible migration pathway of DP. DP concentrations ranged from 14.3 to 245.5 pg/g dry weight in the surface sediments, displaying a seaward increasing trend with the high levels in the central mud zone. This spatial distribution pattern was ascribed to that fine particles with the elevated DP levels were preferentially transported to the central mud zone under hydrodynamic forcing and/or via long-range atmospheric transportation and deposition. DP concentrations in sediment core gradually increased from the mid-1950s to present, which corresponded well with the historical production and usage of DP, as well as the economic development in China. Significantly positive correlation between DP and total organic carbon (TOC) in both surface sediments and sediment core indicated TOC-dependent natural deposition of DP in the SYS. We used multiple biomarkers, for the first time, to explore the potential effects of terrestrial and marine organic matters (TOM and MOM) on DP deposition. The results showed that competition may occur between TOM and MOM for DP adsorption, and MOM was the predominant contributor in controlling DP deposition in the marine sediments from the SYS.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/química , Compostos Policíclicos/química , Poluentes Químicos da Água/análise , Adsorção , Biomarcadores/análise , China , Meio Ambiente , Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Compostos Policíclicos/análise , Poluentes Químicos da Água/química
19.
Sci Total Environ ; 580: 1309-1317, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28040223

RESUMO

Congener profiles, distribution and sources of parent and alkyl-polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Southern Yellow Sea (SYS), China were investigated. The ecological risk of parent-PAHs to aquatic organisms were evaluated based on sediment quality guidelines (SQGs), risk quotient (RQ), organic carbon (OC)-normalized analysis and mean effects range-median quotient (M-ERM-Q). The concentrations of 33 PAHs were analyzed, including 14 parent PAHs (without naphthalene and acenaphthylene), 16 alkyl-PAHs (7 methylphenanthrenes, 3 methylanthracenes, 3 methylfluoranthenes, and 3 methylpyrenes), dibenzothiophene, retene and perylene. Total concentrations of PAHs (TPAHs) ranged from 200.8 to 3629.0ng/g dry weight (d.w.), with a mean value of 1035.4ng/g d.w., and mainly contributed by fluorene, phenanthrene, methylphenanthrene, retene, fluoranthene and pyrene. Analysis of a broad variety of diagnostic ratios suggested that combustion was the key source of PAHs. Principal component analysis-multiple linear regression (PCA-MLR) indicated that combustion of coal, softwood and nature gas, coke oven, petroleum and vehicle emission were the main sources of PAHs in sediments of SYS, contributing 41.5%, 30.6%, 18.8%, and 9.0% to TPAHs, respectively. Ecological risk assessment of individual parent-PAHs suggested that fluorene, phenanthrene and fluoranthene may cause some risk to aquatic organisms in some stations. OC-normalized analysis and M-ERM-Q indicated that risk of multiple parent-PAHs was quite low in the studied area.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Oceanos e Mares , Medição de Risco
20.
Sci Total Environ ; 573: 389-396, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27572532

RESUMO

Dechlorane Plus (DP) is a highly chlorinated flame retardant and found to be ubiquitously present in the environment. We reported here the first record of DP in sediments from the coastal East China Sea (ECS). DP was detected in most of the surface sediments, and the concentrations ranged from 14.8 to 198pg/g dry weight (dw) with a mean value of 64.4pg/g dw. Overall, DP levels exhibited a seaward decreasing trend from the inshore toward outer sea. The fractional abundance of anti-DP (fanti) showed regional discrepancies, attributing to different environmental behaviors of DP isomers. Depth profiles of DP in a sediment core from estuarine environment showed distinct fluctuation, and the core in open sea had stable deposition environment with two peak values of DP in ~1978 and 2000. The fanti exhibited downward decreasing trend prior to mid-1950s, indicating a preferential degradation of anti-DP and/or a greater adsorption capacity of syn-DP after its burial. Lignin and lipid biomarkers (∑C27+C29+C31n-alkanes) of terrestrial organic matters were introduced to identify region-specific sources of DP, and the results showed that DP in the northern inner shelf, southern inner shelf of 29 °N and mud area southwest of Cheju Island was mainly come from Yangtze River (YR) input, surface runoffs after discharge of local sources close to the Taizhou-Wenzhou Region and the atmospheric deposition from the North China and East Asia, respectively. The coastal ECS was an important reservoir of DP in the world, with mass inventory of approximately 310.7kg in the surface sediments (0-5cm).


Assuntos
Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Compostos Policíclicos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Adsorção , China , Isomerismo , Análise Espacial
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