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1.
Nat Commun ; 11(1): 2237, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32382018

RESUMO

Developing localized climate mitigation strategies needs an understanding of how global consumption drives local carbon dioxide (CO2) emissions with a fine spatial resolution. There is no study that provides a spatially explicit mapping of global carbon footprint in China-the world's largest CO2 emitter-simultaneously considering both international and interprovincial trade. Here we map CO2 emissions in China driven by global consumption in 2012 at a high spatial resolution (10 km × 10 km) using a detailed, firm-level emission inventory. Our results show that the carbon footprints of foreign regions in China are concentrated in key manufacturing hubs, including the Yangtze River Delta, Pearl River Delta, and North China Plain. Approximately 1% of the land area holds 75% of the global carbon footprint in China. The carbon footprint hotspots in China identified are the key places in which collaborative mitigation efforts between China and downstream parties that drive those emissions.

2.
J Environ Manage ; 264: 109852, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32364953

RESUMO

In order to integrate resource consumption, environmental damage and ecological benefits into the evaluation system of social and economic development, and practice the green concept of "Lucid waters and lush mountains are invaluable assets", this research was based on the Green GDP and Gross Ecosystem Product accounting to develop comprehensive accounting indicators for Gross Economic-Ecological Product (GEEP). At the same time, the 2016 GEEP of 31 provinces in China is calculated. The results show that: 1) GEEP is a comprehensive ecological-economic accounting system based on weak sustainable development theory and welfare economics. GEEP follows the principle of GDP accounting and carries out value accounting for the final products of ecological and economic systems. Based on GDP, GEEP considers the ecological-environmental damage caused by human beings in economic product activities and the benefits of the ecological system to the economic system. 2) In 2016, China's GEEP was 126.6 trillion RMB, 1.6 times of GDP, among them, the cost of pollution damage was 2.1 trillion RMB, the ecological degradation cost was 0.69 trillion RMB, and the ecosystem regulating service was 51.4 trillion RMB. 3) The regional Gini coefficient based on GEEP was 0.44, which was 0.07 smaller than the regional Gini coefficient calculated based on GDP in 2016, thus GEEP accounting would benefit to shrink regional disparity. 4) Compared GEEP ranking with GDP ranking of all provinces, GEEP rankings in Inner Mongolia, Heilongjiang, Yunnan, Qinghai and Tibet have increased by more than 10 ranks compared with GDP, and Beijing, Shanghai, Tianjin, Hebei and Shaanxi, their GEEP ranking compared with the GDP ranking has descending more than 10 places.


Assuntos
Desenvolvimento Econômico , Ecossistema , Pequim , China , Humanos , Tibet
3.
Waste Manag ; 103: 305-313, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31923839

RESUMO

In this paper, three sets of laboratory tests were conducted on high-food-waste-content (HFWC-), no-food-waste-content (NFWC-) and decomposed (D-) MSWs to characterize their compression behaviors. The immediate compression ratios C'c were 0.30, 0.23 and 0.18 for HFWC-MSW, NFWC-MSW and D-MSW respectively, and tended to increase with the increasing food waste content of MSW. The release of intra-particle water contained in food waste contributed over 23.6-29.2% to immediate compression for HFWC-MSW. The mechanical creep ratios C'sc were 0.02, 0.015 and 0.01 for HFWC-MSW, NFWC-MSW and D-MSW respectively. A prediction model for C'sc was proposed which incorporated the effects of moisture content, dry unit weight and organic waste content. The bio-compression ratios C'sbI, C'sbII and C'sbIII in response to degradation stage I, II and III were 0.12, 0.10 and 0.02 for HFWC-MSW, and were 0.01, 0.15 and 0.01 for NFWC-MSW. Bio-compression is dominant in stage I and II and mechanical creep is the major contributor in stage III for HFWC-MSW, but to NFWC-MSW, mechanical creep is dominant in stage I and III, and bio-compression takes the main position in stage II. The bio-compression tended to increase linearly with leachate draining rate for HFWC-MSW, and the release of intra-particle water contributed 61.9-65.6% to bio-compression. A new model was proposed that can well capture the highly non-linear behavior of bio-compression for both HFWC-MSW and NFWC-MSW. Based on the above findings, the settlement behavior of HFWC-MSW and NFWC-MSW landfills was compared, and suggestions for technique-efficient and cost-effective design of a NFWC-MSW landfill were discussed.


Assuntos
Eliminação de Resíduos , China , Alimentos , Pressão , Resíduos Sólidos , Instalações de Eliminação de Resíduos
4.
New Phytol ; 225(4): 1531-1544, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31257603

RESUMO

Wood formation is the terminal differentiation of xylem mother cells derived from cambial initials, and negative regulators play important roles in xylem differentiation. The molecular mechanism of the negative regulator of xylem differentiation PagKNAT2/6b was investigated. PagKNAT2/6b is an ortholog of Arabidopsis KNAT2 and KNAT6 that is highly expressed in phloem and xylem. Compared to nontransgenic control plants, transgenic poplar plants overexpressing PagKNAT2/6b present with altered vascular patterns, characterized by decreased secondary xylem with thin cell walls containing less cellulose, xylose and lignin. RNA sequencing analyses revealed that differentially expressed genes are enriched in xylem differentiation and secondary wall synthesis functions. Expression of NAM/ATAF/CUC (NAC) domain genes including PagSND1-A1, PagSND1-A2, PagSND1-B2 and PagVND6-C1 is downregulated by PagKNAT2/6b, while PagXND1a is directly upregulated. Accordingly, the dominant repression form of PagKNAT2/6b leads to increased xylem width per stem diameter through downregulation of PagXND1a. PagKNAT2/6b can inhibit cell differentiation and secondary wall deposition during wood formation in poplar by modulating the expression of NAC domain transcription factors. Direct activation of PagXND1a by PagKNAT2/6b is a key node in the negative regulatory network of xylem differentiation by KNOXs.

5.
J Environ Manage ; 255: 109485, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31790866

RESUMO

Different regions in China face greatly dissimilar ecological and environmental problems due to large variations in natural conditions and socioeconomic development levels. Such spatial variability calls for regionalized environmental management and protection policies. Environmental function zoning is an effective tool for the design and implementation of differentiated environmental policies. To contain the ecological degradation in different regions of China, we first created a comprehensive environmental function evaluation index system that included 25 socioeconomic and environmental indicators for the three key elements of natural ecological security protection, healthy human living environment maintenance, and regional environment carrying capacity. To clarify the division of Chinese environmental function zoning in the new period, we use GIS and remote sensing technology. We generated 1-km resolution grid data for the 25 indicators and implemented this index system to evaluate the environmental function of the 2414 counties in China. Differentiated environmental management objectives and strategies were designed and implemented for different zones to avoid the phenomenon of one size fits all. This work lays a scientific foundation and provides a quantitative tool for the design and implementation of differentiated management. By considering not only the natural system but also the social and economic systems and their interactions, this evaluation of environmental function provides a more comprehensive view and thus offers new insights on balancing environmental protection and socioeconomic development.


Assuntos
Conservação dos Recursos Naturais , Política Ambiental , China , Planejamento de Cidades , Ecologia , Ecossistema , Humanos
6.
J Exp Bot ; 71(4): 1503-1513, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31665748

RESUMO

In plants, a large root system improves the uptake of water and nutrients, and is important for responding to drought stress. The poplar WUSCHEL-related homeobox (WOX) transcription factor promotes adventitious rooting, but its regulation of root growth in response to drought stress remains elusive. In this study, we found that PagWOX11/12a from hybrid poplar 84K (Populus alba×Populus glandulosa) is expressed predominantly in the roots and is strongly induced by drought stress. Compared with non-transgenic 84K plants, transgenic poplar plants overexpressing PagWOX11/12a displayed increased root biomass and enhanced drought tolerance, while opposite phenotypes were observed for PagWOX11/12a dominant repression plants. PagWOX11/12a functions as a nuclear transcriptional activator with a transactivation domain at the C-terminus. In addition, PagERF35 was found to specifically bind to a dehydration-responsive element (DRE) within the PagWOX11/12a promoter and activate PagWOX11/12a gene expression. These results indicate that PagERF35 may activate PagWOX11/12a expression in response to drought stress by promoting root elongation and biomass, thereby increasing drought tolerance of poplar.

7.
Proc Natl Acad Sci U S A ; 116(49): 24463-24469, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31740599

RESUMO

From 2013 to 2017, with the implementation of the toughest-ever clean air policy in China, significant declines in fine particle (PM2.5) concentrations occurred nationwide. Here we estimate the drivers of the improved PM2.5 air quality and the associated health benefits in China from 2013 to 2017 based on a measure-specific integrated evaluation approach, which combines a bottom-up emission inventory, a chemical transport model, and epidemiological exposure-response functions. The estimated national population-weighted annual mean PM2.5 concentrations decreased from 61.8 (95%CI: 53.3-70.0) to 42.0 µg/m3 (95% CI: 35.7-48.6) in 5 y, with dominant contributions from anthropogenic emission abatements. Although interannual meteorological variations could significantly alter PM2.5 concentrations, the corresponding effects on the 5-y trends were relatively small. The measure-by-measure evaluation indicated that strengthening industrial emission standards (power plants and emission-intensive industrial sectors), upgrades on industrial boilers, phasing out outdated industrial capacities, and promoting clean fuels in the residential sector were major effective measures in reducing PM2.5 pollution and health burdens. These measures were estimated to contribute to 6.6- (95% CI: 5.9-7.1), 4.4- (95% CI: 3.8-4.9), 2.8- (95% CI: 2.5-3.0), and 2.2- (95% CI: 2.0-2.5) µg/m3 declines in the national PM2.5 concentration in 2017, respectively, and further reduced PM2.5-attributable excess deaths by 0.37 million (95% CI: 0.35-0.39), or 92% of the total avoided deaths. Our study confirms the effectiveness of China's recent clean air actions, and the measure-by-measure evaluation provides insights into future clean air policy making in China and in other developing and polluting countries.

8.
J Environ Manage ; 252: 109603, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586746

RESUMO

Air pollution control has become one of the top priorities of China's "Ecological Civilization" development. As a quick response to the 2013 PM2.5 episodes, the Chinese Government issued the "Air Pollution Prevention and Control Action Plan" as the national strategy and roadmap for air quality improvements consisting of phased quantitative targets and concrete measures. Taking this into account, this study explores the spatiotemporal variations of the five conventional pollutants-PM2.5, PM10, SO2, NO2, and O3-as well as the Air Quality Index and primary pollutants in 338 Chinese cities from 2013 to 2017 in order to comprehensively understand China's current air pollution situation and evaluate the effectiveness of the Action Plan. The results indicate that: (1) the overall air quality has been significantly improved, with the concentrations of PM2.5, PM10, and SO2 decreasing noticeably, although the still high PM level, the dramatically increasing O3 concentration, and the stagnant amounts of NO2 present further challenges, along with the intensification of regional compound air pollution problems; (2) in contrast to the three key regions under the Action Plan exhibiting significant decreases in PM and SO2, the Fen-Wei Plain (FWP) is suffering from serious compound pollution, suggesting that there is an urgent need for the development of a regional joint prevention and control mechanism in the FWP and similar areas; (3) with the exception of the common pollution hot spots mainly concentrated in the FWP as well as Beijing-Tianjin-Hebei (BTH) and its surrounding regions, the distribution of each pollutant exhibited remarkable spatial heterogeneity due to their distinctive emission sources, a finding that strongly indicates the need for regionally differentiated management; and (4) the most frequent primary pollutant at the national level was O3, followed by PM2.5 and PM10. In the Wuhan Metropolitan Area (WHM), Changsha-Zhuzhou-Xiangtan Metropolitan Area (CZT), and Sichuan-Chongqing Region (CY), PM2.5 pollution is playing the dominant role, while in the FWP, BTH, Yangtze River Delta region (YRD), and Pearl River Delta region (PRD), the synergistic control of PM2.5 and O3 pollutants is urgently needed as soon as possible, which will require that more attention be paid to emission mitigation in the transportation sector, as well as the synergistic control of NOx and VOC emissions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Pequim , China , Cidades , Monitoramento Ambiental , Material Particulado , Melhoria de Qualidade
9.
J Environ Manage ; 251: 109501, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31542624

RESUMO

China is continually seeking to improve river water quality. Implemented in 1996, the total pollutant load control system (TPLCS) is a regulatory strategy to reduce total pollutant loads, under which a Pollutant Discharge Permit (PDP) program tracks and regulates nutrient inputs from point source polluters. While this has been promising, the input-response relationship between discharge permits and water quality targets is largely unclear - especially in China's large and complex river basins. In response, this study involved a quantitative analysis method to combine the water quality targets of the 12th Five-Year Plan (2011-2015) with allocated PDPs in the Nenjiang River Basin, China. We demonstrated our approach by applying the Soil and Water Assessment Tool (SWAT) to the Nenjiang River Basin for hydrological and water quality simulation. Ammonia nitrogen (NH3-N) was used as the primary water quality indicator. Modelling indicated that only one control section in the wider river basin did not achieve the water quality target, suggesting that the TPLCS is largely effective. The framework should be applied in other basins to study the effectiveness of PDP policies, advise further updates to the TPLCS, and ultimately aim to achieve freshwater quality targets nationally.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , China , Monitoramento Ambiental , Nitrogênio , Rios
10.
J Environ Manage ; 249: 109400, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31445371

RESUMO

Heavy metal pollution is posing a serious threat to ecosystem and human health in China. In addition to being emitted into the atmosphere, heavy metals generated by industrial processes are also emitted into water bodies. However, there is a lack of research exploring trade-induced aquatic heavy metals (AHM) emissions hidden in cross-regional supply chain networks. Such information can provide both consumer and producer perspectives on stakeholders' responsibility and involve them in pollution control along the entire supply chain including influencing consumption choices. Using a bottom-up AHM emission inventory (including mercury (Hg), cadmium (Cd), chromium (Cr), arsenic (As), and lead (Pb)) in 2010, we firstly accounted for production- and consumption-based AHM emissions and their virtual flows between China's 30 provinces. Additionally, we developed an integrated index, i.e. Equal Risk Pollution Load, to measure the risk associated with five AHM based on the corresponding reference dose. We found that richer provinces Guangdong, Jiangsu and Zhejiang through their consumption of metal products caused aquatic Hg, Cd, As and Pb pollution in provinces with nonferrous-metallic mineral resources such as Hunan, Yunnan, and Inner Mongolia. However, virtual aquatic Cr emissions were incurred in richer coastal regions (e.g. Guangdong, Zhejiang) for producing and exporting high value added products (electroplated products, printed circuit board and leather products) to less developed inland provinces. Finally, we propose measures from a supply chain perspective to mitigate aquatic pollution.


Assuntos
Mercúrio , Metais Pesados , China , Ecossistema , Monitoramento Ambiental , Poluição Ambiental , Humanos
11.
ACS Appl Mater Interfaces ; 11(30): 27402-27409, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31288511

RESUMO

In this study, we have prepared a novel superhydrophilic fabric that has underwater directional oil-transport capability. The fabric was prepared using a two-step process consisting of dip-coating of a cross-linkable polymer, which comprises both oleophilic and hydrophilic groups, onto the fabric substrate and single-side UV irradiation of the coated fabric. The fabric had in-air superhydrophilicity on both sides, and it can be wetted easily once immersed in water. The treated fabric showed underwater oleophobicity on the UV-exposed surface, whereas the unexposed back side still maintained underwater oleophilicity. At the optimized condition, the fabric in water transports oil automatically from the UV-exposed to the unexposed back side but stops oil transport in the opposite direction. Such a directional oil transport takes place without the need for oil prewetting or formation of a plastron layer on fabric. The UV irradiation time showed an effect on oil-transport ability. We further showed that the underwater directional oil-transport fabric had a novel "oil trapping" ability. When used to seal a container, the fabric can trap oil into the container, and once trapped, the oil was kept without releasing. This underwater directional oil-transport fabric may be useful for the development of high-efficiency oil recovery systems.

12.
J Environ Manage ; 247: 561-569, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260922

RESUMO

An emission permit system (EPS) is a fixed-source environmental management system that is widely practiced worldwide. Since 2016, China has been building a fixed-source environmental management system with the EPS as its core. This paper summarizes the evolutionary process of China's EPS over the past 40 years considering four main stages: embryonic stage, local pilot stage, total emission control-based exploration stage, and reform stage of the core management system. This paper notes that China initially established a system of laws and technical specifications for emission permits, and emission permits are clearly becoming a mainstream trend in fixed-source management. The paper argues that there are still four problems in the current EPS reform (i.e., insufficient support of laws and regulations, poor integration of the EPS with other systems, unscientific design of the EPS, and insufficient implementation capacity after permit allocation). This paper puts forward 7 suggestions for further EPS reform, e.g., accelerating the formulation of the regulations on the EPS, strengthening the coordination with other fixed-source systems, improving the technical support system for the EPS, establishing a database system for emission permits, building a scientific and reasonable allocation method, improving the autonomy of pollutant monitoring in enterprises, and increasing information disclosure and public participation. The results may more accurately evaluate China's EPS in China's environmental protection system, provide scientific support for the promotion and development of the ongoing EPS reform and environmental management systems. The results may promote the development of pollution prevention, and an improvement in the environmental quality in China, and offer scientific guidance and reference for other countries to implement their own EPS.


Assuntos
Conservação dos Recursos Naturais , Poluição Ambiental , China
13.
Sci Total Environ ; 684: 390-401, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31154212

RESUMO

Equitable and efficient allocation of pollutant discharge permits is vital for controlling total pollutant amounts. However, the conventional water pollutant discharge permit allocation method is criticized for dividing the environmental attributes of water bodies, which is mainly based on administrative units. China is establishing a water ecological environment zoning management system to manage the water environment more scientifically, which may have a great impact on for controlling total pollutant amounts. Whether the ecological environment zoning management system can promote more equitable and efficient permit allocation remains unknown. In this paper, an environmental zoning system and "basin-region" correlation are established to take both regional and watershed allocation processes into consideration. Then, a multi-index Gini coefficient method is established to evaluate the equality of different allocating methods. The Gini coefficient is then combined with a linear interactive and general optimizer method to achieve an equitable allocation of ammonia nitrogen discharge permits in the Songhua River Basin from both watershed and regional perspectives. Forty-five water pollutant discharge allocation scenarios are considered to represent different manager tendencies. The results show that allocation based on watershed functional units is more equitable than that based on administrative units. The index weighting settings also have a large impact on regional and total equality and environmental efficiency. Midstream and downstream areas show large allocation differences, although no scenario can satisfy all watershed regions in terms of equality and environmental efficiency at the same time. Thus, more trade-offs are needed during decision making. By considering the coordination of social, environmental and economic development at the basin level, this study provides new insight into equitable and efficient allocation. Moreover, the findings suggest that an environmental zoning system should be considered for discharge permit allocation in water resource management.

14.
MethodsX ; 6: 1036-1043, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31193181

RESUMO

This paper presents a method to solidify/stabilize the municipal solid waste incineration (MSWI) fly ash by originally employing the microbial induced carbonate precipitation (MICP) technique. In this method, the rich endogenous calcium in the MSWI fly ash was utilized to induce calcite precipitation, which is different from the operation of adding extra calcium source in previous researches. The fly ash sample had a CaO content of 44.5%, and its leaching concentrations of Zn, Cr and Pb exceed the limits of the identification standard for hazardous wastes in China. The optical density at 600 nm (OD600) of the bacterial solution was about 1.0 after the processes of bacterial activation and reproduction. The prepared fly ash sample was well mixed with bacterial solution at an ash-liquid ratio of 1 kg: 0.3 L and cured at a temperature of 20 °C and a humidity of ≥95% for 7 days. After treatment, the heavy metal leachability significantly reduced to meet the standard for pollution control of landfill site, and the unconfined compressive strength increased approximately 40%. The precipitated carbonates were verified by SEM-EDS analysis and quantified by measurement of carbonate content via acid-dissolving method. The results shone a light on the possibility of using MICP technique as a useful and efficient tool to stabilize the MSWI fly ash before being reused or properly stored in landfills. •The MICP method is efficient to reduce the heavy metal leachability and increase the compressive strength of MSWI fly ash.•The endogenous calcium in MSWI fly ash was utilized to induce calcite precipitation.•The heavy metals in MSWI fly ash were well immobilized by the formation of carbonates.

15.
Artigo em Inglês | MEDLINE | ID: mdl-30934562

RESUMO

Indoor fine particulate matter (PM2.5) and its chemical composition is important for human exposure as people spend most of their time indoors. However, few studies have investigated the multiseasonal characteristics of indoor PM2.5 and its chemical composition in China. In this study, the chemical composition of PM2.5 samples in residences was analyzed over four seasons in Nanjing, China. Indoor water-soluble ions exhibited similar seasonal variations (winter > autumn > summer > spring) to those from outdoors (winter > autumn > spring > summer) except in summer. Whereas, indoor metallic elements exhibited a different seasonal pattern from that of outdoors. The highest concentrations of indoor metallic elements were observed in summer when the outdoor concentrations were low. The different seasonal variations of the chemical composition between indoor and outdoor PM2.5 indicated that people should consider both indoor and outdoor sources to reduce their exposure to air pollutants in different seasons. The carcinogenic risks for metallic elements were within the acceptable levels, while manganese (Mn) was found to have potential noncarcinogenic risk to humans. More attention should be paid to the pollution of Mn in the study area in the future. Moreover, the cumulative effect of noncarcinogenic PM2.5-bound elements should not be ignored.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Material Particulado/análise , China , Cidades , Habitação , Estações do Ano
16.
J Magn Reson Imaging ; 50(4): 1055-1062, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30861249

RESUMO

BACKGROUND: Presence of intraplaque hemorrhage (IPH) is a known risk factor for stroke and plaque progression. Accurate and reproducible measurement of IPH volume are required for further risk stratification. PURPOSE: To develop a semiautomatic method to measure carotid IPH volume. STUDY TYPE: Retrospective. POPULATION: Patients scheduled for carotid endarterectomy and patients with 16-79% asymptomatic carotid stenosis by ultrasound. FIELD STRENGTH: 3T. SEQUENCE: Simultaneous noncontrast angiography and intraplaque hemorrhage (SNAP) MRI. ASSESSMENT: A semiautomated volumetric measurement of IPH using signal intensity thresholding of 3D SNAP volume was implemented. Fourteen carotid endarterectomy patients were enrolled to determine the signal intensity threshold of IPH using histology. Thirty-three patients with 16-79% asymptomatic stenosis were scanned twice within 1 month to evaluate reproducibility. The normalized SNAP intensity with the highest Youden index for predicting IPH on histology was used for thresholding. Scan-rescan reproducibility of IPH measurement was assessed using the intraclass correlation coefficient (ICC) and coefficient of variation (CV). STATISTICAL TESTS: Receiver operating characteristic curve, area under the curve, Cohen's kappa, intraclass correlation coefficient, coefficient of variance (CV), and paired t-test. RESULTS: IPH detection by the algorithm had substantial agreement with manual review (kappa: 0.92; 95% confidence interval [CI]: 0.83, 1.00) and moderate agreement with histology (kappa: 0.55; 95% CI: 0.34, 0.68). IPH volume measurements by the algorithm were strongly correlated with histology (Spearman's rho = 0.76, P = 0.002). IPH measurements were also reproducible, with ICCs of 0.86 (95% CI: 0.57, 0.96), 0.77 (95% CI: 0.32, 0.94), and 0.99 (95% CI: 0.93, 1.00) for maximum/mean normalized intensity and IPH volume, respectively. The corresponding CVs were 10.6%, 5.2%, and 11.8%. DATA CONCLUSION: IPH volume measurements on SNAP MRI are highly reproducible using semiautomatic measurement. Level of Evidence 2 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2019;50:1055-1062.

17.
Artigo em Inglês | MEDLINE | ID: mdl-30621102

RESUMO

Indoor fine particulate matter (PM2.5) is important since people spend most of their time indoors. However, knowledge of the spatiotemporal variations of indoor PM2.5 concentrations within a city is limited. In this study, the spatiotemporal distributions of indoor PM2.5 levels in Nanjing, China were modeled by the multizone airflow and contaminant transport program (CONTAM), based on the geographically distributed residences, human activities, and outdoor PM2.5 concentrations. The accuracy of the CONTAM model was verified, with a good agreement between the model simulations and measurements (r = 0.940, N = 110). Two different scenarios were considered to examine the building performance and influence of occupant behaviors. Higher PM2.5 concentrations were observed under the scenario when indoor activities were considered. Seasonal variability was observed in indoor PM2.5 levels, with the highest concentrations occurring in the winter and the lowest occurring in the summer. Building characteristics have a significant effect on the spatial distribution of indoor PM2.5 concentrations, with multistory residences being more vulnerable to outdoor PM2.5 infiltration than high-rise residences. The overall population exposure to PM2.5 in Nanjing was estimated. It would be overestimated by 16.67% if indoor exposure was not taken into account, which would lead to a bias in the health impacts assessment.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Material Particulado/análise , Análise Espaço-Temporal , China , Cidades , Monitoramento Ambiental , Habitação/estatística & dados numéricos , Humanos , Características de Residência , Estações do Ano , Transportes
18.
Tree Physiol ; 39(3): 381-390, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30307572

RESUMO

Growth-regulating factors (GRFs) are involved in various developmental events, particularly leaf development. However, the functions of GRFs in woody plants remain elusive. In this study, functional characterization of GRF15 in Populus was performed. Most GRFs are preferentially expressed in young leaves. As GRF15 was expressed at the highest level and with highest ratio in Populus species with large leaves, this gene was investigated through transgenic analyses. Promotor-ß-glucuronidase analysis revealed expression of GRF15 at the leaf expansion zone. Additionally, GRF15 was found to be localized in the nucleus and regulated by miR396. Leaf size and palisade cell size were significantly increased and decreased in GRF15-overexpressing and dominant repression lines, respectively. Consistently, expression of EXPA11a, a homolog of cell-expansion marker EXPA11 in Arabidopsis, was strongly upregulated and downregulated in the GRF15-overexpressing and dominant repression lines, respectively, which was further manifested by activation of EXPA11a by GRF15 in transactivation assays. Therefore, GRF15 is required for leaf size control and primarily modulates cell expansion during leaf development in Populus.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Populus/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/genética , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Populus/crescimento & desenvolvimento
19.
Genomics ; 111(4): 700-709, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29660475

RESUMO

Branching in woody plants affects their ecological benefits and impacts wood formation. To obtain genome-wide insights into the transcriptome changes and regulatory mechanisms associated with branching, we performed high-throughput RNA sequencing to characterize cDNA libraries generated from active buds of Populus deltoides CL. 'zhonglin2025' (BC) and Populus × zhaiguanheibaiyang (NC). NC has more branches than BC and rapid growth. We obtained a total of 198.2 million high-quality clean reads from the NC and BC libraries. We detected 3543 differentially expressed genes (DEGs) between the NC and BC libraries; 1418 were down-regulated and 2125 were up-regulated. Gene ontology functional classification of the DEGs indicated that they included 89 genes that encoded proteins related to hormone biosynthesis, 364 genes related to hormone signaling transduction, and 104 related to the auxin efflux transmembrane transporter. We validated the expression profiles of 16° by real-time quantitative PCR and found that their expression patterns were similar to those obtained from the high-throughput RNA sequencing data. We also measured the hormone content in young buds of BC and NC by high-pressure liquid chromatography. In this study, we identified global hormone regulatory patterns and differences in gene expression between NC and BC, and constructed a hormone regulatory network to explain branching in Populus buds. In addition, candidate genes that may be useful for molecular breeding of particular plant types were identified. Our results will provide a starting point for future investigations into the molecular mechanisms of branching in Populus.


Assuntos
Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Planta/genética , Proteínas de Plantas/genética , Populus/genética , Transcriptoma , Flores/genética , Flores/crescimento & desenvolvimento , Lactonas/metabolismo , Reguladores de Crescimento de Planta/biossíntese , Proteínas de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Populus/crescimento & desenvolvimento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
Sci Adv ; 4(7): eaar8400, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29978044

RESUMO

China's CH4 emissions from 1955 existing (old) and 495 planned (new) landfills are estimated and projected by adopting a bottom-up method, targeting a 2012 baseline year and a 2030 projected target year. Nine key CH4 mitigation measures are proposed for the CH4 mitigation assessment from landfills. Approximately 0.66 million metric tons (Mt) of CH4 and 1.14 Mt of CH4 will be released, respectively, from new and existing landfills under a 2030 business-as-usual (BAU) scenario, which is 23.5% lower than a U.S. Environmental Protection Agency estimation. It is estimated that 0.60 and 0.97 Mt of CH4 can be reduced under new policies (NP) and low-carbon (LC) policy scenarios, respectively. The combined biocover and landfill gas collection and flaring system is the most promising mitigation measure, while mechanical biological treatment and mineral landfill also contribute substantially to CH4 reduction. The odor-affected population under NP and LC scenarios will decrease by 39.5 and 64.2%, respectively, when compared to the 2030 BAU scenario. The LC scenario is a recommended policy for meeting China's nationally determined contribution targets and reducing the not-in-my-backyard impact due to this policy's significant reduction of CH4 emissions.


Assuntos
Metano/análise , Instalações de Eliminação de Resíduos , China , Monitoramento Ambiental/métodos , Política Ambiental
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