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1.
Artigo em Inglês | MEDLINE | ID: mdl-32372538

RESUMO

For Li-Se batteries, ether- and carbonate-based electrolytes are commonly used. However, because of the "shuttle effect" of the highly dissoluble long-chain lithium polyselenides (LPSes, Li2 Sen , 4≤n≤8) in the ether electrolytes and the sluggish one-step solid-solid conversion between Se and Li2 Se in the carbonate electrolytes, a large amount of porous carbon (>40 wt % in the electrode) is always needed for the Se cathodes, which seriously counteracts the advantage of Se electrodes in terms of volumetric capacity. Herein an acetonitrile-based electrolyte is introduced for the Li-Se system, and a two-plateau conversion mechanism is proposed. This new Li-Se chemistry not only avoids the shuttle effect but also facilitates the conversion between Se and Li2 Se, enabling an efficient Se cathode with high Se utilization (97 %) and enhanced Coulombic efficiency. Moreover, with such a designed electrolyte, a highly compact Se electrode (2.35 gSe cm-3 ) with a record-breaking Se content (80 wt %) and high Se loading (8 mg cm-2 ) is demonstrated to have a superhigh volumetric energy density of up to 2502 Wh L-1 , surpassing that of LiCoO2 .

2.
Sci Total Environ ; 735: 139542, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32447070

RESUMO

The effect of lockdown due to coronavirus disease (COVID-19) pandemic on air pollution in four Southern European cities (Nice, Rome, Valencia and Turin) and Wuhan (China) was quantified, with a focus on ozone (O3). Compared to the same period in 2017-2019, the daily O3 mean concentrations increased at urban stations by 24% in Nice, 14% in Rome, 27% in Turin, 2.4% in Valencia and 36% in Wuhan during the lockdown in 2020. This increase in O3 concentrations is mainly explained by an unprecedented reduction in NOx emissions leading to a lower O3 titration by NO. Strong reductions in NO2 mean concentrations were observed in all European cities, ~53% at urban stations, comparable to Wuhan (57%), and ~65% at traffic stations. NO declined even further, ~63% at urban stations and ~78% at traffic stations in Europe. Reductions in PM2.5 and PM10 at urban stations were overall much smaller both in magnitude and relative change in Europe (~8%) than in Wuhan (~42%). The PM reductions due to limiting transportation and fuel combustion in institutional and commercial buildings were partly offset by increases of PM emissions from the activities at home in some of the cities. The NOx concentrations during the lockdown were on average 49% lower than those at weekends of the previous years in all cities. The lockdown effect on O3 production was ~10% higher than the weekend effect in Southern Europe and 38% higher in Wuhan, while for PM the lockdown had the same effect as weekends in Southern Europe (~6% of difference). This study highlights the challenge of reducing the formation of secondary pollutants such as O3 even with strict measures to control primary pollutant emissions. These results are relevant for designing abatement policies of urban pollution.


Assuntos
Poluição do Ar/análise , Infecções por Coronavirus , Monitoramento Ambiental , Ozônio/análise , Pandemias , Pneumonia Viral , Betacoronavirus , China , Cidades , Europa (Continente) , Humanos , Dióxido de Nitrogênio/análise , Material Particulado/análise
3.
Nano Lett ; 20(3): 1747-1754, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32027140

RESUMO

Plasmonic nanostructures have a wide range of applications, including chemical and biological sensing. However, the development of techniques to fabricate submicrometer-sized plasmonic structures over large scales remains challenging. We demonstrate a high-throughput, cost-effective approach to fabricate Au nanoribbons via chemical lift-off lithography (CLL). Commercial HD-DVDs were used as large-area templates for CLL. Transparent glass slides were coated with Au/Ti films and functionalized with self-assembled alkanethiolate monolayers. Monolayers were patterned with lines via CLL. The lifted-off, exposed regions of underlying Au were selectively etched into large-area grating-like patterns (200 nm line width; 400 nm pitch; 60 nm height). After removal of the remaining monolayers, a thin In2O3 layer was deposited and the resulting gratings were used as plasmonic sensors. Distinct features in the extinction spectra varied in their responses to refractive index changes in the solution environment with a maximum bulk sensitivity of ∼510 nm/refractive index unit. Sensitivity to local refractive index changes in the near-field was also achieved, as evidenced by real-time tracking of lipid vesicle or protein adsorption. These findings show how CLL provides a simple and economical means to pattern large-area plasmonic nanostructures for applications in optoelectronics and sensing.

4.
Sci Total Environ ; 713: 136676, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32019032

RESUMO

The West China Rain Zone (WCRZ) is of ecological importance and thus, anthropogenic impacts on its vitality are of concern. To ascertain if China's SO2 and NOx emissions reductions in the recent years are reflected in reduced impacts, sulfur and nitrogen wet deposition at Mt. Emei was observed during 2017-2019. The source contributions to sulfur and nitrogen wet deposition were estimated using the positive matrix factorization (PMF) and the source-oriented Community Multi-scale Air Quality (CMAQ) model. The annual Volume Weighted Mean (VWM) pH of precipitation increased from 4.01 to 4.75 in the 1980s-2000s to 5.39 in 2017-2019. However, 12% of the samples during 2017-2019 had pH < 4.50. The VWM SO42- concentration decreased from 80.9 to 26.0 µeq L-1 from 2007-2009 to 2017-2019. The VWM NO3- concentration (18.3 µeq L-1) in 2017-2019 was close to that measured in 2007-2009. Although the dry deposition fluxes onto forest canopy were under-estimated, the mean annual total wet and dry deposition flux of nitrogen (24.3 kg N ha-1 yr-1) was higher than the critical load (CL: 10.0-15.0 kg N ha-1 yr-1), while the flux of sulfur (12.1 kg S ha-1 yr-1) was lower than the CL (16.0-32.0 kg S ha-1 yr-1). The annual wet deposition fluxes of SO42- and NO3- were mainly from industries (54% and 43%, respectively) and power plants (21% and 25%, respectively), and that of NH4+ was mostly from agriculture (88%). Emissions within and outside the Sichuan Basin (SCB) were both important sources of the wet deposition fluxes of sulfur (45% and 39%, respectively) and nitrogen (68% and 29%, respectively), and other unidentified sources accounted for 16% and 3% of the sulfur and nitrogen fluxes, respectively. This study suggests that to protect Mt. Emei's ecosystems, efforts are needed to further control sulfur and nitrogen deposition through reducing emissions within and outside the SCB.

5.
Bull Environ Contam Toxicol ; 104(4): 432-437, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32072197

RESUMO

Metalaxyl is broadly applied in agriculture to control peronosporales-caused diseases in plant. To investigate the toxic effects, zebrafish embryos were exposed to metalaxyl at 5, 50 and 500 ng/L for 72 h, the development of larvae were assessed. A significant decreased survival rate, body length, hatching rate (48 h post-fertilization), and a significant increased spinal curvature rate were observed in the 500 ng/L treatment. The lengths of lower jaw, upper jaw and hyomandibular were significantly decreased in the 5, 50 and 500 ng/L groups; while the lower jaw width was significantly increased in the 500 ng/L group. The lengths of palatoquadrate, ceratohyal and ethmoid plate were reduced. Though cyp26a1 mRNA levels showed no significant change, the transcription of bmp2b (in the 500 ng/L group), ihh (in the 50 and 500 ng/L groups), shh (in the 5, 50 and 500 ng/L groups) were significantly up-regulated, which may be related to the abnormal development of the skeleton.


Assuntos
Alanina/análogos & derivados , Osso e Ossos/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Alanina/toxicidade , Animais , Osso e Ossos/embriologia , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento
6.
ISA Trans ; 99: 110-122, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31522822

RESUMO

In the Dempster-Shafer theory (DST) of evidence, the alarm evidence updating-based method can effectively deal with the uncertainty of the monitored process variable so as to significantly reduce the false alarm rates (FAR) and missed alarm rates (MAR) of the industrial alarm system. But the price of the decrease of FAR and MAR is the increase of the averaged alarm delay (AAD). In order to obtain better comprehensive performance, besides the accuracy indices (FAR and MAR), the sensitivity index (AAD) should be considered simultaneously in the alarm system parameter optimization design. In the framework of DST, firstly, this paper defines the static and dynamical performance indices in the alarm evidence space which are compatible with FAR/MAR/AAD in the process variable space. But the former can measure the performance of the DST-based alarm systems more naturally and elaborately than the latter; secondly, a systematic parameter optimization design procedure for the alarm system is investigated by using these new indices and the tradeoff among them. Finally, two typical numerical experiments and an industrial case are provided to illustrate the effectiveness of the static and dynamical indices for improving the comprehensive performance of the DST-based alarm systems.

7.
Biosci Biotechnol Biochem ; 84(2): 290-296, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31619134

RESUMO

Chromosome region maintenance 1 (CRM1) plays a critical role in tumorigenesis and progression through modulating nuclear export of several proteins. However, the precise effects of CRM1 inhibitor on gastric carcinoma have not yet been illustrated. Here, we investigated the potential anti-cancer activities of leptomycin B, the most potent CRM1 antagonist, on cultured gastric carcinoma cells. Our findings demonstrate that CRM1 was highly expressed in four gastric carcinoma cell lines. Leptomycin B inhibited the viability of HGC-27 and AGS cells in a dose- and time-dependent pattern. Leptomycin B at the dose of 10 nM or 100 nM suppressed the migration and invasion of HGC-27 and AGS cells. Leptomycin B elevated the expressions of autophagy-related protein LC3-II and autophagy substrate p62. Moreover, leptomycin B enhanced the LC3-positive puncta formation in cells. Our data suggest that leptomycin B may exert an anti-cancer activity possibly through interfering autophagy function in gastric carcinoma cells.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Invasividade Neoplásica/prevenção & controle , Neoplasias Gástricas/patologia , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ácidos Graxos Insaturados/farmacologia , Humanos , Carioferinas/antagonistas & inibidores , Carioferinas/metabolismo , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo
8.
Environ Pollut ; 257: 113621, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761581

RESUMO

Atmospheric ammonia (NH3) as the most important alkaline gas in the atmosphere has attracted much attention in recent years due to its critical role in haze formation, especially on the North China Plain (NCP). Comprehensive studies are needed for investigating diurnal variations of NH3 and underlying mechanisms in different seasons and their potential impacts on atmospheric chemistry. In this study, continuous long-term observation (Mar. 2016 to May 2017) of NH3 at a rural site in the NCP was used to characterize the diurnal variation of NH3 in different seasons and to unveil its causes and potential impacts on atmospheric chemistry. NH3 concentrations displayed rapid increases during the morning, reaching very prominent peaks mostly between 8:00 to 11:00 LT. Such frequent (55%) morning peaks were mainly caused by the evaporation of dew and guttation water droplets. Average dew and guttation water volume concentrations of 750 mL m-2 was estimated for spring, which resulted in approximate NH3 emissions of 800 ng m-2 s- 1. Such high emission fluxes from dew and guttation water evaporation have never been reported before, suggesting dew and guttation droplets to be significant night-time reservoirs and strong morning sources for NH3. In light of recent studies putting forward that NH3 can promote the heterogeneous formation of HONO and nitrate under high humidity conditions, we investigated the differences in HONO and aerosol chemical composition diurnal variations between days with and without NH3 morning spikes during November. HONO, nitrate and sulfate concentrations were significantly higher for days with NH3 morning spikes, with HONO displaying a morning peak near that of NH3. These results demonstrate that the prevailing NH3 morning spikes on the NCP have significant influences on aerosol formation and atmospheric chemistry. NH3 emission mitigation strategies and regulations are urgently needed.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Amônia/análise , Monitoramento Ambiental , China
9.
Bioresour Technol ; 297: 122387, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31735696

RESUMO

This work developed a novel two-stage bioprocess for electricity generation from bakery waste (BW). In the first stage, commercial glucoamylase was utilized to hydrolyze the BW to produce soluble BW hydrolysate. It was found that 100 g BW could be converted to 32 g hydrolysis solid and 760 mL BW hydrolysate. The highest glucose production of 21.9 g/L could be achieved within 5 h. In the second stage, the soluble BW hydrolysate was utilized as feedstock for electricity generation in microbial fuel cell (MFC). The maximum voltage of 0.386 V was obtained. The power density reached a peak value of 29.96 mW/m2 when the external resistance was 1090 Ω. It could be potentially utilized to transform high-starch containing raw materials into biofuels production which could reduce the cost of biofuels production effectively for industrial application.


Assuntos
Fontes de Energia Bioelétrica , Biocombustíveis , Eletricidade , Glucana 1,4-alfa-Glucosidase , Hidrólise
10.
Appl Opt ; 58(35): 9603-9613, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31873559

RESUMO

This paper proposes an improved calibration method for a structured light system by using the random sample consensus (RANSAC) method with nonlinear optimization and an improved gray centroid method. The proposed method is composed of two steps: calibrating intrinsic and extrinsic parameters for the camera, exploiting the improved gray centroid method to extract the centerline, and fitting the structured light plane by the RANSAC approach with the three-dimensional (3D) points obtained from different positions. The error function caused by the extracted centerline is deduced based on the pixel error perturbation method. The error results of the 3D points are simulated and analyzed. An imaging system is built to realize the 3D imaging. The experimental results show that the calibration error is within 0.08 mm and the reconstruction error is less than 0.45 mm. Moreover, it performs better for the reconstruction of complex objects compared with traditional methods.

11.
PLoS One ; 14(10): e0223899, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618250

RESUMO

Post-translational modifications (PTMs) of therapeutic monoclonal antibodies (mAbs) are important product quality attributes (PQAs) that can potentially impact drug stability, safety, and efficacy. The PTMs of a mAb may change remarkably in the bloodstream after drug administration compared to in vitro conditions. Thus, monitoring in vivo PTM changes of mAbs helps evaluate the criticality of PQAs during the product risk assessment. In addition, quantitation of the subject exposures to PTM variants helps assess the impact of PTMs on the safety and efficacy of therapeutic mAbs. Here, we developed an immunocapture-liquid chromatography/mass spectrometry (LC/MS) method to quantify in vivo PTM changes a therapeutic mAb overtime in single- and multiple-dose monkey pharmacokinetic (PK) studies. We also built mathematical models to predict the in vivo serum concentrations of PQAs, the subject exposures to PQAs, and the relative abundance of PQAs in single- and multiple-dose regimens. The model predictions are in good agreement with the experimental results. The immunocapture-LC/MS method and mathematical models enable bioanalytical chemists to quantitatively assess the criticality of PQAs during drug development.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/metabolismo , Animais , Anticorpos Monoclonais/farmacocinética , Cromatografia Líquida/métodos , Esquema de Medicação , Estabilidade de Medicamentos , Feminino , Haplorrinos , Humanos , Modelos Teóricos , Processamento de Proteína Pós-Traducional , Espectrometria de Massas em Tandem/métodos
12.
Sensors (Basel) ; 19(17)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484311

RESUMO

MEMS-based skin friction sensors are used to measure and validate skin friction and its distribution, and their advantages of small volume, high reliability, and low cost make them very important for vehicle design. Aiming at addressing the accuracy problem of skin friction measurements induced by existing errors of sensor fabrication and assembly, a novel fabrication technology based on visual alignment is presented. Sensor optimization, precise fabrication of key parts, micro-assembly based on visual alignment, prototype fabrication, static calibration and validation in a hypersonic wind tunnel are implemented. The fabrication and assembly precision of the sensor prototypes achieve the desired effect. The results indicate that the sensor prototypes have the characteristics of fast response, good stability and zero-return; the measurement ranges are 0-100 Pa, the resolution is 0.1 Pa, the repeatability accuracy and linearity are better than 1%, the repeatability accuracy in laminar flow conditions is better than 2% and it is almost 3% in turbulent flow conditions. The deviations between the measured skin friction coefficients and numerical solutions are almost 10% under turbulent flow conditions; whereas the deviations between the measured skin friction coefficients and the analytical values are large (even more than 100%) under laminar flow conditions. The error resources of direct skin friction measurement and their influence rules are systematically analyzed.


Assuntos
Pele , Animais , Técnicas Biossensoriais , Fricção , Humanos , Sistemas Microeletromecânicos
13.
Sci Total Environ ; 673: 378-383, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30991327

RESUMO

In this study, utilization of waste cake for bioethanol production via a two-step of enzymatic hydrolysis and ethanol fermentation was developed. At the first step, namely waste cake hydrolysis, effects of α-amylase volumes (C1: 0.1 mL/L, C2: 0.4 mL/L, C3, 0.8 mL/L) on the performance of hydrolysis were investigated. Both chemical oxygen demand (COD) and reducing sugar (RS) could reach the highest values after 80 min for all the conditions. The maximum COD of 86.3 g/L, RS of 44 g/L and waste reduction of 85.2% were achieved at C3. At the second step, namely ethanol fermentation, the produced waste cake hydrolysate was used as the sole feedstock for fermentative ethanol production, and the highest ethanol production of 46.6 g/L and ethanol yield of 1.13 g/g RS were obtained (C3), respectively. This corresponds to an overall ethanol yield of 1.12 g ethanol/g initial dry cake which is the highest ethanol yield compared to using other food wastes reported to date. These values are higher than using the glucose as feedstock since the waste cake hydrolysate could provide the carbon and nitrogen sources for ethanol fermentation.


Assuntos
Biocombustíveis , Etanol , Fermentação , Resíduos/análise , Alimentos , Hidrólise , Gerenciamento de Resíduos/métodos
14.
ACS Appl Mater Interfaces ; 11(15): 13984-13990, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30855935

RESUMO

The function of biological nanoparticles, such as membrane-enveloped viral particles, is often enhanced when the particles form higher-order supramolecular assemblies. While there is intense interest in developing biomimetic platforms that recapitulate these collective properties, existing platforms are limited to mimicking individual virus particles. Here, we present a micropatterning strategy to print linker molecules selectively onto bioinert surfaces, thereby enabling controlled tethering of biomimetic viral particle clusters across defined geometric patterns. By controlling the linker concentration, it is possible to tune the density of tethered particles within clusters while enhancing the signal intensity of encapsulated fluorescent markers. Time-resolved tracking of pore formation and membrane lysis revealed that an antiviral peptide can disturb clusters of the membrane-enclosed particles akin to the targeting of individual viral particles. This platform is broadly useful for evaluating the performance of membrane-active antiviral drug candidates, whereas the micropatterning strategy can be applied to a wide range of biological nanoparticles and other macromolecular entities.


Assuntos
Antivirais/química , Vírion/efeitos dos fármacos , Sequência de Aminoácidos , Antivirais/farmacologia , Lipossomos/química , Microscopia de Fluorescência , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polilisina/análogos & derivados , Polilisina/química , Vírion/metabolismo
15.
Sci Rep ; 9(1): 953, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700755

RESUMO

The profound changes in global SO2 emissions over the last decades have affected atmospheric composition on a regional and global scale with large impact on air quality, atmospheric deposition and the radiative forcing of sulfate aerosols. Reproduction of historical atmospheric pollution levels based on global aerosol models and emission changes is crucial to prove that such models are able to predict future scenarios. Here, we analyze consistency of trends in observations of sulfur components in air and precipitation from major regional networks and estimates from six different global aerosol models from 1990 until 2015. There are large interregional differences in the sulfur trends consistently captured by the models and observations, especially for North America and Europe. Europe had the largest reductions in sulfur emissions in the first part of the period while the highest reduction came later in North America and East Asia. The uncertainties in both the emissions and the representativity of the observations are larger in Asia. However, emissions from East Asia clearly increased from 2000 to 2005 followed by a decrease, while in India a steady increase over the whole period has been observed and modelled. The agreement between a bottom-up approach, which uses emissions and process-based chemical transport models, with independent observations gives an improved confidence in the understanding of the atmospheric sulfur budget.

16.
Virol J ; 16(1): 16, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717759

RESUMO

BACKGROUND: To examine the epidemiological trends and changes of hepatitis E virus (HEV) infection and the potential risk factors for severe infection in the Zhejiang eastern coastal area of China. METHODS: We analyzed statutory hepatitis E cases notifications and inpatient data held by the national surveillance and hospital information systems in Wenzhou, Taizhou, Ningbo, and Zhoushan cities of the Zhejiang eastern coastal area of China. RESULTS: Nine thousand four hundred sixteen hepatitis E cases were reported from 2004 to 2017, with an average incidence of 2.94 per 100,000. The overall death rate was 0.06% (6/9416). A gradual decline of hepatitis E cases was found in the coastal areas since 2007, while a rise was identified in the non-coastal areas. Annual incidence in non-coastal cities was much higher than that in coastal cities (4.345 vs. 2.945 per 100,000, relative risk = 1.5, P value < 0.001). The mean age was 52 years old and 50.55 years with a male-to-female ratio of 2.32:1 and 2.21:1 in coastal and noncoastal areas respectively (all P > 0.05). Hepatitis E cases prevalence increased with age, highest among men in their 70s (9.02 vs. 11.33 per 100,000) and women in their 60s (3.94 vs. 4.66 per 100,000) groups for both coastal and noncoastal areas respectively. A clear seasonal pattern was observed, with a peak in March (0.4429 per 100,000) in coastal areas. 202 inpatients were documented, of which 50.50% (102/202) were severe cases. Male individuals with alcohol consumption, alcohol hepatic diseases, and superinfection were the three independent highest risks for severe infections (all with P value < 0.05). CONCLUSIONS: This is to our knowledge the largest epidemiological study of hepatitis E cases in the eastern coastal area of Zhejiang province of China. The patterns of infection across the coastal areas were similar to those of the non-coastal areas, but the incidence was substantially lower and decreased gradually since 2007.


Assuntos
Monitoramento Epidemiológico , Hepatite E/epidemiologia , Hospitais/estatística & dados numéricos , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Vírus da Hepatite E , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estações do Ano , Adulto Jovem
17.
Brain Behav ; 9(3): e01225, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30761779

RESUMO

INTRODUCTION: Bisphenol A (BPA) is an endocrine disruptor widely used to manufacture consumer goods. Although the thyroid hormone (TH) disrupting potential of BPA has been thought to be responsible for the neuropsychiatric deficits in the animals that experienced perinatal BPA exposure, the TH availability change at the level of specific brain structures has not been subject to systematic investigation. METHODS: In the present study the impacts of perinatal BPA exposure (0.1 mg/L in drinking water) spanning gestation and lactation on TH homeostasis in the prefrontal cortex (PFC) and hippocampus were assessed in male Sprague-Dawley rats at postnatal day 21 (PND21) and PND90. As TH regulates brain glucose metabolism at multiple levels,the effects of BPA treatment on glucose metabolism in the brain tissues were also assessed in adult rats. RESULTS: The results showed heterogeneous changes in TH concentration induced by BPA between serum and brain tissues, additionally, in the BPA-treated pups, up-regulated expression of the TH transporter monocarboxylate 8 mRNA at PND21 and increased type 3 iodothyronine deiodinase mRNA expressions at PND21 and PND90 were observed. Meanwhile, decreased glucose metabolism was seen in the PFC and hippocampus, while deficits in locomotor activity, spatial memory and social behaviors occurred in BPA-treated groups. CONCLUSION: These data support the concept that the developing brain possesses potent mechanisms to compensate for a small reduction in serum TH, such as serum hypothyrodism induced by BPA exposure, however, the long-term negative effect of BPA treatment on TH homeostasis and glucose metabolism may be attributable to neuropsychiatric deficits after mature.


Assuntos
Compostos Benzidrílicos/farmacologia , Glucose/metabolismo , Hipocampo , Fenóis/farmacologia , Córtex Pré-Frontal , Efeitos Tardios da Exposição Pré-Natal , Hormônios Tireóideos/metabolismo , Animais , Disruptores Endócrinos/farmacologia , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Sprague-Dawley , Memória Espacial/efeitos dos fármacos , Regulação para Cima
18.
J Environ Sci (China) ; 77: 291-302, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30573093

RESUMO

We investigated the seasonal and spatial ozone variations in China by using three-year surface ozone observation data from the six Chinese Global Atmosphere Watch (GAW) stations and tropospheric column ozone data from satellite retrieval over the period 2010-2012. It is shown that the seasonal ozone variations at these GAW stations are rather different, particularly between the western and eastern locations. Compared with western China, eastern China has lower background ozone levels. However, the Asian summer monsoon (ASM) can transport photochemical pollutants from the southern to the northern areas in eastern China, leading to a northward gradual enhancement of background ozone levels at the eastern GAW stations. Over China, the tropospheric column ozone densities peak during spring and summer in the areas that are directly and/or indirectly affected by the ASM, and the peak time lags from the south to the north in eastern China. We also investigated the regional representativeness of seasonal variations of ozone at the six Chinese GAW stations using the yearly maximum tropospheric column month as indicator. The results show that the seasonal variation characteristics of ozone revealed by the Chinese GAW stations are typical, with each station having a considerable large surrounding area with the ozone maximum occurring at the same month. Ozone variations at the GAW stations are influenced by many complex factors and their regional representativeness needs to be investigated further in a broader sense.


Assuntos
Atmosfera/química , Monitoramento Ambiental , Ozônio/análise , Estações do Ano , China
19.
Elementa (Wash D C) ; 1: 1, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30345319

RESUMO

Assessment of spatial and temporal variation in the impacts of ozone on human health, vegetation, and climate requires appropriate metrics. A key component of the Tropospheric Ozone Assessment Report (TOAR) is the consistent calculation of these metrics at thousands of monitoring sites globally. Investigating temporal trends in these metrics required that the same statistical methods be applied across these ozone monitoring sites. The nonparametric Mann-Kendall test (for significant trends) and the Theil-Sen estimator (for estimating the magnitude of trend) were selected to provide robust methods across all sites. This paper provides the scientific underpinnings necessary to better understand the implications of and rationale for selecting a specific TOAR metric for assessing spatial and temporal variation in ozone for a particular impact. The rationale and underlying research evidence that influence the derivation of specific metrics are given. The form of 25 metrics (4 for model-measurement comparison, 5 for characterization of ozone in the free troposphere, 11 for human health impacts, and 5 for vegetation impacts) are described. Finally, this study categorizes health and vegetation exposure metrics based on the extent to which they are determined only by the highest hourly ozone levels, or by a wider range of values. The magnitude of the metrics is influenced by both the distribution of hourly average ozone concentrations at a site location, and the extent to which a particular metric is determined by relatively low, moderate, and high hourly ozone levels. Hence, for the same ozone time series, changes in the distribution of ozone concentrations can result in different changes in the magnitude and direction of trends for different metrics. Thus, dissimilar conclusions about the effect of changes in the drivers of ozone variability (e.g., precursor emissions) on health and vegetation exposure can result from the selection of different metrics.

20.
Science ; 362(6412): 319-324, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30190311

RESUMO

Detection of analytes by means of field-effect transistors bearing ligand-specific receptors is fundamentally limited by the shielding created by the electrical double layer (the "Debye length" limitation). We detected small molecules under physiological high-ionic strength conditions by modifying printed ultrathin metal-oxide field-effect transistor arrays with deoxyribonucleotide aptamers selected to bind their targets adaptively. Target-induced conformational changes of negatively charged aptamer phosphodiester backbones in close proximity to semiconductor channels gated conductance in physiological buffers, resulting in highly sensitive detection. Sensing of charged and electroneutral targets (serotonin, dopamine, glucose, and sphingosine-1-phosphate) was enabled by specifically isolated aptameric stem-loop receptors.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Dopamina/análise , Glucose/análise , Lisofosfolipídeos/análise , Serotonina/análise , Esfingosina/análogos & derivados , Esfingosina/análise , Transistores Eletrônicos
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