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1.
J Environ Manage ; 368: 122147, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39142108

RESUMEN

Urban agglomeration (UA) plays as the main carrier of economy and society in China, concentrating the human activities, energy consumptions, and subsequent carbon emissions in space. The policy-induced mechanism of carbon emissions in the units of UA is currently less explored, and diversities of low-carbon development path of UAs remain unknown. Thus, this study analyzes the carbon emissions of 19 UAs in China from 2006 to 2019, focuses on the low-carbon city pilot policy (LCPP), constructs an SDM-DID model to investigate the impacts of LCPP on carbon emissions regionally, and delineates the stages of low-carbon development in UAs based on the theory of Environmental Kuznets Curve. The results show that carbon emissions of China's UAs are spatially distributed as higher in the east but lower in the west, and increase faster in the central. The effect of LCPP on carbon emissions is significant but inhibitory in the central and northeastern UAs, while it becomes insignificant in the eastern ones. Finally, the low-carbon development paths of all UAs are divided into Type I, strong Type I, Type II, Type III, and Type IV stage. The eastern UAs are all at Type I stage because they are more sensitive and ahead in terms of low-carbon development strategies. The findings of this study can provide references for city groups to formulate carbon reduction policies and decouple the relations between economic development and carbon emissions.


Asunto(s)
Carbono , Ciudades , China , Carbono/análisis , Humanos , Urbanización , Monitoreo del Ambiente , Proyectos Piloto
2.
Environ Sci Pollut Res Int ; 31(40): 53291-53303, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39186204

RESUMEN

To compare the different effects of petroleum hydrocarbons on intertidal Ulva macroalgae, three dominant Ulva species (U. prolifera, U. linza, and U. lactuca) were exposed to two water-accommodated fractions (WAFs) of 0# diesel oil and crude oil at three concentration levels. The results indicated that two WAFs had significant concentration effects on the physiological characteristics of Ulva, the toxicity of 0# diesel oil was greater than crude oil, and crude oil had hormesis effect. Exposure of high WAFs concentrations, the growth, pigment, carbohydrate, and protein contents of Ulva were inhibited, while the antioxidant system was activated. In addition, the integrated biomarker response (IBR) indicated that U. prolifera had higher resistance to WAFs than U. linza and U. lactuca. Considering that U. prolifera is the main species of green tide in the Yellow Sea (YS) of China, the comparative effects of WAFs on different development stages of U. prolifera were also explored. The results showed that spore was the most sensitive to WAFs, while adult thalli was the most tolerant. The increased resistance of U. prolifera thalli and the hormesis effect triggered by crude oil may influence the outbreak scale of green tides. This study provides a new perspective for understanding the formation of green tides in the YS.


Asunto(s)
Hidrocarburos , Petróleo , Ulva , Ulva/efectos de los fármacos , Petróleo/toxicidad , Hidrocarburos/toxicidad , Contaminantes Químicos del Agua/toxicidad , China
3.
Sci Total Environ ; 920: 171079, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38373460

RESUMEN

Elevated atmospheric nitrogen (N) deposition on terrestrial ecosystems has become one of the most important drivers of microbial diversity loss on a global scale, and has been reported to alter the soil function of nutrient-poor, montane Calluna vulgaris heathlands in the context of global change. In this work we analyze for the first time the shifts of bacterial communities in response to experimental addition of N in Calluna heathlands as a simulation of atmospheric deposition. Specifically, we evaluated the effects of five N addition treatments (0, 10, 20, and 50 kg N ha-1 yr-1 for 3-years; and 56 kg N ha-1 yr-1 for 10-years) on the resistance of soil bacterial communities as determined by changes in their composition and alpha and beta diversities. The study was conducted in montane Calluna heathlands at different development stages (young and mature phases) in the southern side of the Cantabrian Mountains (NW Spain). Our results evidenced a substantial increase of long-term (10-years) N inputs on soil extractable N-NH4+, particularly in young Calluna stands. The alpha diversity of soil bacterial communities in mature Calluna stands did not show a significant response to experimental N addition, whereas it was significantly higher under long-term chronic N addition (56 kg N ha-1 yr-1 for 10-years) in young Calluna stands. These bacterial community shifts are mainly attributable to a decrease in the dominance of Acidobacteria phylum, the most representative in montane Calluna ecosystems, in favor of copiotrophic taxa such as Actinobacteria or Proteobacteria phyla, favored under increased N availability. Future research should investigate what specific ecosystem functions performed by soil bacterial communities may be sensitive to increased nitrogen depositions, which may have substantial implications for the understanding of montane Calluna ecosystems' stability.


Asunto(s)
Calluna , Ecosistema , Suelo , España , Nitrógeno/análisis , Proteobacteria , Calluna/fisiología , Microbiología del Suelo
4.
Animals (Basel) ; 13(24)2023 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-38136838

RESUMEN

To investigate the shifts in the biochemical composition of hybrid grouper during the early larval stages, we collected samples at various developmental milestones, spanning from newly hatched larvae (stage I) to 4 days after hatching (stage V). Our findings revealed several notable trends: (1) The total length of hybrid grouper larvae exhibited a significant increase as the yolk-sac absorption progressed from stage I to V. Concurrently, there was a marked decrease in yolk volume and oil volume during the transition from stage I to III, followed by a gradual decline from stage III to V. (2) Dry weight and total lipid content displayed a rapid reduction throughout the larval development period, while the total protein content exhibited a declining trend. (3) The concentrations of triacylglycerols and wax esters/steryl esters decreased considerably, particularly at stage V. However, no differences were observed among the contents of ketones, hydrocarbons, and sterols. (4) As yolk-sac larvae developed from stage I to V, a significant reduction was observed in the levels of essential amino acids (EAAs), such as leucine, valine, isoleucine, phenylalanine, glycine, alanine, serine, proline, and tyrosine. This trend was also observed for non-EAAs and total amino acids, with fluctuations in the content of other amino acids. (5) There was a significant decrease in the levels of specific fatty acids, including C16:0, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), C18:0, 18:1n-9, and C20:4n-6. In contrast, the contents of C22:6n-3, polyunsaturated fatty acids (PUFAs), n-3 PUFA, n-6 PUFA, and the combination of docosahexaenoic acid (DHA) + eicosapentaenoic acid (EPA), as well as the DHA/EPA ratio, remained stable from stage I to III but declined thereafter. (6) During the early developmental stages, the utilization sequence of fatty acids followed a pattern of prioritizing SFAs, followed by MUFAs, n-6 PUFA, and n-3 PUFA. These findings provide further insights into the nutritional priorities of hybrid grouper larvae during their early development, with a particular emphasis on lipids and fatty acids as vital energy sources. Additionally, our results highlight variations in the efficiency of utilization among different types of fatty acids, while protein utilization remained relatively stable, characterized by the selective consumption of amino acid content.

5.
Environ Monit Assess ; 195(12): 1525, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37994954

RESUMEN

The analysis of landslide susceptibility is a crucial tool in the mitigation and management of ecological and economic hazards. The number of studies examining how the form and durability of forest areas affect landslide susceptibility is very limited. This study was conducted in the Marmara region of northwestern Türkiye, where forested areas and industrial zones are intertwined and dense. The landslide susceptibility map was produced by Analytic Hierarchy Process (AHP) method. In the context of AHP, a total of 12 different variables were employed, namely lithology, slope, curvatures, precipitations, aspect, distance to fault lines, distance to streams, distance to roads, land use, soil, elevation, and Normalized Difference Vegetation Index (NDVI). The performance analysis of the landslide susceptibility map was conducted using the Receiver Operating Characteristics (ROC) curve method. The AUC value was computed (0.809) for the landslide susceptibility map generated by using the AHP technique. Forest type maps were used to analyze the impact of forests on landslide susceptibility. In terms of forest structure, 4 main criteria were determined: stand structure, development stage, crown closure, and stand age. Each criterion was analyzed with Geographic Information Systems (GIS) by overlaying it with the landslide susceptibility map of the study area. The results showed that the risk of landslides was lowest in forests with more than one tree species, mature, development stage and of (e) > 52 cm, and crown closure of 41%-70% (2).


Asunto(s)
Ecosistema , Deslizamientos de Tierra , Proceso de Jerarquía Analítica , Monitoreo del Ambiente/métodos , Sistemas de Información Geográfica , Bosques
6.
Animals (Basel) ; 13(22)2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38003198

RESUMEN

The development and growth of porcine skeletal muscle determine pork quality and yield. While genetic regulation of porcine skeletal muscle development has been extensively studied using various omics data, the role of transposable elements (TEs) in this context has been less explored. To bridge this gap, we constructed a comprehensive atlas of TE expression throughout the developmental stages of porcine skeletal muscle. This was achieved by integrating porcine TE genomic coordinates with whole-transcriptome RNA-Seq data from 27 developmental stages. We discovered that in pig skeletal muscle, active Tes are closely associated with active epigenomic marks, including low levels of DNA methylation, high levels of chromatin accessibility, and active histone modifications. Moreover, these TEs include 6074 self-expressed TEs that are significantly enriched in terms of muscle cell development and myofibril assembly. Using the TE expression data, we conducted a weighted gene co-expression network analysis (WGCNA) and identified a module that is significantly associated with muscle tissue development as well as genome-wide association studies (GWAS) of the signals of pig meat and carcass traits. Within this module, we constructed a TE-mediated gene regulatory network by adopting a unique multi-omics integration approach. This network highlighted several established candidate genes associated with muscle-relevant traits, including HES6, CHRNG, ACTC1, CHRND, MAMSTR, and PER2, as well as novel genes like ENSSSCG00000005518, ENSSSCG00000033601, and PIEZO2. These novel genes hold promise for regulating muscle-related traits in pigs. In summary, our research not only enhances the TE-centered dissection of the genetic basis underlying pork production traits, but also offers a general approach for constructing TE-mediated regulatory networks to study complex traits or diseases.

7.
Front Microbiol ; 14: 1251627, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37744901

RESUMEN

Cotton bollworm (Helicoverpa armigera) poses a global problem, causing substantial economic and ecological losses. Endosymbionts in insects play crucial roles in multiple insect biological processes. However, the interactions between H. armigera and its symbionts have not been well characterized to date. We investigated the symbionts of H. armigera in the whole life cycle from different geographical locations. In the whole life cycle of H. armigera, Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria were the dominant bacteria at the phylum level, while Enterococcus, Enterobacter, Glutamicibacter, and Bacillus were the four dominant bacteria at the genus level. Furthermore, high similarity in symbiotic bacterial community was observed in different stages of H. armigera, which were dominated by Enterococcus and Enterobacter. In fields, the dominant bacteria were Proteobacteria and Bacteroidetes, whereas, in the laboratory, the dominant bacteria were Proteobacteria. At the genus level, the dominant bacteria in cotton bollworm eggs of wild populations were Enterobacter, Morganella, Lactococcus, Asaia, Apibacter, and Enterococcus, and the subdominant bacteria were Bartonella, Pseudomonas, and Orbus. Moreover, the symbionts varied with geographical locations, and the closer the geographical distance, the more similar the microbial composition. Taken together, our study identifies and compares the symbiont variation along with geographical gradients and host development dynamic and reveals the high flexibility of microbiome communities in H. armigera, which probably benefits for the successful survival in a complicated changing environment.

8.
Poult Sci ; 102(9): 102900, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37406441

RESUMEN

Excess abdominal fat is a common phenomenon in broiler chickens. Gut microbiota could regulate lipid metabolism through their effects on short-chain fatty acids (SCFAs) production. This study was conducted to investigate the potential relationship between abdominal fat development and cecal microorganism populations. Abdominal fat and cecum contents were collected at 3, 7, 14, 21, 28, 35, and 42 d of age. The results showed that abdominal fat weight increased with age. The abdominal fat percentage was higher between 7 and 21 d of age than at 3 d (P < 0.05), and it increased again at 28 to 42 d (P < 0.05). Morphological analysis showed that adipocyte diameter and cross-sectional area (CSA) increased significantly after 14 d of age (P < 0.05). Moreover, gut microbiota analysis indicated that the Chao1 and Shannon indices were higher between 14 and 28 d than at 3 d of age (P < 0.05). Furthermore, LEfse analysis revealed that Faecalibacterium, Anaerotruncus, Anaeroplasma, Subdoligranulum, and Clostridium emerged to become dominant at 14 d. A greater abundance of Bacteroides, Ruminococcus, Dehalobacterium, and Lactobacillus were determined at 28 d when compared with 14 d of age. Parabacteroides, Ochrobactrum, Lactobacillus, Blautia, Alistipes, Dehalobacterium, Odoribacter, and Suuterella were found to be predominant at 42 d. PICRUSt analysis revealed that amino acid metabolism, lipid metabolism, and terpenoids and polyketides metabolism were elevated at 14 d; the immune and digestive systems were significantly developed at 28 d. In addition, cecum propionic acid and butyric acid contents gradually increased (P < 0.05), while the isobutyric acid contents gradually decreased with advancing age (P < 0.05). Correlation analysis among SCFAs, differential genera and abdominal fat suggested that Coprobacillus, Shigella, and Butyricicoccus had negative correlations with propionic acid, butyric acid, and abdominal fat weight, but positive correlations with isobutyric acid. Isobutyric acid was identified as being negatively associated with abdominal fat weight, while the reverse was found for propionic acid and butyric acid. In conclusion, abdominal fat development is correlated with the emergence of specific microbes and d 14 may be a pivotal age for establishing this relationship.


Asunto(s)
Microbioma Gastrointestinal , Animales , Propionatos/metabolismo , Pollos/fisiología , Isobutiratos/metabolismo , Bacteroidetes , Ácidos Grasos Volátiles/metabolismo , Ciego/microbiología
9.
J Environ Manage ; 339: 117795, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37071951

RESUMEN

Fiscal transfer payments (TRANS) are the institutional supplement of Chinese-style fiscal decentralization, which is of great significance to economic development. However, the relationship between TRANS and energy conservation and emission reduction (ECER) remains to be further discussed. Using panel data of 30 provinces in China from 2003 to 2020, this study empirically examines the impact of TRANS on energy-environmental performance (EEP) from the perspectives of influence mechanism, regional heterogeneity and nonlinearity. The results show that the influence of TRANS on ECER presents an obvious U-shaped relationship, and this influence has regional heterogeneity. At the same time, the investment-driven effect, infrastructure effect and industrial structure effect are important channels through which TRANS affect ECER. The partially linear functional coefficient models show that TRANS have different effects in different development stages. With the continuous improvement of economic level and urbanization level, the promotion effect of TRANS on ECER is more and more obvious. These results indicate that the government should increase fiscal investment in ECER, and pay attention to the development stage of different regions.


Asunto(s)
Gobierno , Urbanización , China , Desarrollo Económico , Inversiones en Salud , Política
10.
Artículo en Inglés | MEDLINE | ID: mdl-36554528

RESUMEN

The value of ecosystem services is an extremely important parameter that reflects regional ecological benefits and resources. Estimating the value of ecosystem services is essential for regional land-use optimization, ecological construction, and biodiversity protection. In this study, Landsat-TM/ETM remote sensing images were used to analyze land-use data in 1990, 2000, 2010, and 2020 of the Yellow River Basin (Henan section), China, defined by natural boundaries. An equivalent factor method was used to construct a model to calculate the ecosystem services value that introduced grain yield, regional difference coefficient, and social development stage coefficient. Thus, land-use changes and evolution of ecosystem services values in the Yellow River Basin (Henan section) in the past 30 years were analyzed. Land use in the basin changed significantly from 1990 to 2020. Except for an increase in area of construction land, areas of other land-use types decreased. Cultivated land area first increased and then decreased, whereas the water area first decreased and then increased. The total value of ecosystem services in the study area fluctuated but increased overall by 43.82 × 108 USD in the past 30 years. Spatially, the total value of ecosystem services was high in the southwest and low in the northeast. Among individual ecosystem service values, water conservation, gas regulation, and climate regulation accounted for a relatively high proportion of the total value. Regulation services were the main ecosystem service functions, followed by support and supply services, with cultural services accounting for the lowest proportion. Sensitivity coefficients of different land types in different periods were all less than one. Therefore, the value coefficients were reasonable, and the results were consistent with the actual situation of the study area. The study improves the method to estimate the ecosystem services value of the basin and also indicates ways to support ecological protection of the Yellow River Basin (Henan section), China.


Asunto(s)
Ecosistema , Ríos , Conservación de los Recursos Naturales , Agricultura , China
11.
Front Plant Sci ; 13: 1005711, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36420035

RESUMEN

Angelica sinensis is a medicinal plant widely used to treat multiple diseases in Asia and Europe, which contains numerous active components with therapeutic value. The interaction between root and rhizosphere microorganisms is crucial for the growth and quality formation of medicinal plants. But the micro-plant-metabolite regulation patterns for A. sinensis remain largely undetermined. Here, we collected roots and rhizosphere soils from A. sinensis in seedling stage (M) and picking stage (G), respectively cultivated for one year and two years, generated metabolite for roots, microbiota data for rhizospheres, and conducted a comprehensive analysis. Changes in metabolic and microbial communities of A.sinensis over growth were distinct. The composition of rhizosphere microbes in G was dominated by proteobacteria, which had a strong correlation with the synthesis of organic acids, while in M was dominated by Actinobacteria, which had a strong correlation with the synthesis of phthalide and other organoheterocyclic compounds, flavonoids, amines, and fatty acid. Additionally, co-occurrence network analysis identified that Arthrobacter was found to be strongly correlated with the accumulation of senkyunolide A and n-butylidenephthalide. JGI 0001001.H03 was found to be strongly correlated with the accumulation of chlorogenic acid. Based on rhizosphere microorganisms, this study investigated the correlation between root metabolism and rhizosphere microbiota of A. sinensis at different growth stages in traditional geoherb region, which could provide references for exploring the quality formation mechanism of A. sinensis in the future.

12.
Open Life Sci ; 17(1): 1155-1164, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36185405

RESUMEN

Reverse transcription quantitative PCR (RT-qPCR) is a technique widely used to investigate the expression of genes. An appropriate reference gene (RG) is essential for RT-qPCR analysis to obtain accurate and reliable results. Caragana intermedia plays an important role in afforestation as a bush. However, due to the lack of appropriate RGs, the research on development-related genes is limited. In this study, the selection for suitable RGs of different organs at various development stages to normalize the results of RT-qPCR about development-related genes was performed. To test the expression stability across all samples, we used the software algorithms such as geNorm, NormFinder, BestKeeper, and RefFinder to evaluate all the candidate RGs. Our results showed that CiEF1α was the most stable RG with little fluctuation among all samples. In addition, CiGAPDH in roots, CiSKIP1 in stems and leaves, and CiEF1α in different organs were selected as the most stable RGs. To confirm the applicability of the most stable RGs, the relative expression of CiWRKY17 was normalized using different candidate RGs. Taken together, our research laid a foundation for the study of development-related genes in C. intermedia.

13.
J Pers Med ; 12(7)2022 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-35887655

RESUMEN

BACKGROUND: This study aimed to reveal the efficacy of the artificial intelligence (AI)-assisted dental age (DA) assessment in identifying the characteristics of growth delay (GD) in children. METHODS: The panoramic films matching the inclusion criteria were collected for the AI model training to establish the population-based DA standard. Subsequently, the DA of the validation dataset of the healthy children and the images of the GD children were assessed by both the conventional methods and the AI-assisted standards. The efficacy of all the studied modalities was compared by the paired sample t-test. RESULTS: The AI-assisted standards can provide much more accurate chronological age (CA) predictions with mean errors of less than 0.05 years, while the traditional methods presented overestimated results in both genders. For the GD children, the convolutional neural network (CNN) revealed the delayed DA in GD children of both genders, while the machine learning models presented so only in the GD boys. CONCLUSION: The AI-assisted DA assessments help overcome the long-standing populational limitation observed in traditional methods. The image feature extraction of the CNN models provided the best efficacy to reveal the nature of delayed DA in GD children of both genders.

14.
Huan Jing Ke Xue ; 43(3): 1455-1462, 2022 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-35258209

RESUMEN

Currently, research on the effects of microplastics (MPs) in biofilms has mainly been focused on the mature biofilm communities, with a lack of sufficient details on the influence on different development stages of biofilms. Proteus and 1 µm polystyrene microplastics (PS-MPs), which are widely found in the environment, were selected as the research objects to explore the effects of microplastics on biofilms at different developmental stages. In our study, the effects of PS-MPs on biofilm biomass, extracellular polymer composition(EPS), and extracellular enzyme activity were investigated using an exposure test. Our results showed that the effect of PS-MPs on biofilms at different stages was similar, but the effect was significantly reduced with the development of biofilms. Biofilms at different development stages had different sensitivities to microplastics. In the reversible attachment stage, the no observed effect concentration (NOEC) of EPS composition, reactive oxygen species (ROS) production, and extracellular enzyme activity were significantly lower than those in other stages; however, the NOEC of total antioxidant capacity (T-AOC) and lactate dehydrogenase (LDH) activity were similar. This may be the result of ROS-mediated protein oxidation, which can be reduced but not completely eliminated by EPS in other stages of biofilm. This indicates that PS-MPs has a low toxic effect on biofilm.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Biopelículas , Microplásticos/toxicidad , Plásticos , Poliestirenos , Proteus , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
15.
Planta ; 255(4): 86, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35286485

RESUMEN

MAIN CONCLUSION: The characteristics of sorghum anthers at 18 classified developmental stages provide an important reference for future studies on sorghum reproductive biology and abiotic stress tolerance of sorghum pollen. Sorghum (Sorghum bicolor L. Moench) is the fifth-most important cereal crop in the world. It has relatively high resilience to drought and high temperature stresses during vegetative growing stages comparing to other major cereal crops. However, like other cereal crops, the sensitivity of male organ to heat and drought can severely depress sorghum yield due to reduced fertility and pollination efficiency if the stress occurs at the reproductive stage. Identification of the most vulnerable stages and the genes and genetic networks that differentially regulate the abiotic stress responses during anther development are two critical prerequisites for targeted molecular trait selection and for enhanced environmentally resilient sorghum in breeding using a variety of genetic modification strategies. However, in sorghum, anther developmental stages have not been determined. The distinctive cellular characteristics associated with anther development have not been well examined. Lack of such critical information is a major obstacle in the studies of anther and pollen development in sorghum. In this study, we examined the morphological changes of sorghum anthers at cellular level during entire male organ development processes using a modified high-throughput imaging variable pressure scanning electron microscopy and traditional light microscopy methods. We divided sorghum anther development into 18 distinctive stages and provided detailed description of the morphological changes in sorghum anthers for each stage. The findings of this study will serve as an important reference for future studies focusing on sorghum physiology, reproductive biology, genetics, and genomics.


Asunto(s)
Sorghum , Adaptación Fisiológica/genética , Sequías , Grano Comestible , Fitomejoramiento , Sorghum/fisiología
16.
MethodsX ; 9: 101634, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35242617

RESUMEN

In this paper a novel holistic approach to assess the performance of waste management systems (WMSs) is presented. The so called WMS development stage concept (WMS-DSC) can be used by practitioners or decision makers to assess primarily the WMS at the municipal level. The WMS categorization into development stages notably enables a clear identification of symptoms, the causes of possible waste mismanagement and potential measures for improvement. The concept can be used to (i) assess the status quo of a WMS and, based on this, identify possible measures for implementation; (ii) check whether relevant system conditions to implement a specific measure are met; (iii) monitor the progress of a WMS; and (iv) compare the WMSs of different cities. The concept consists of five development stages: stage 1 - absence or lack of essential elements of waste management; stage 2 - reliable collection and improved landfill sites; stage 3 - separate collection and sorting; stage 4 - expansion of the recycling industry; and stage 5 - circular economy (CE), waste as a resource. While stage 1 describes the absence of or a very immature and malfunctioning WMS, stage 5 stands for a fully implemented CE. By equating the highest stage to the objectives that have evolved today globally for a sustainable CE, this concept can be used to identify targets and the most suitable steps for an individual WMS towards a future best practice of CE.•A holistic approach to assess waste management systems' performance is presented.•A benchmarking tool to estimate the circular economy (CE) evolvement in cities.•Usable for cities both in the Global North and South to identify CE potentials.

17.
Environ Sci Pollut Res Int ; 29(31): 46991-47010, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35175532

RESUMEN

Exploring the changes in ecological networks (ENs), its eco-environment effects and the differences in urban agglomerations in various urbanization stages are important for achieving sustainable ecosystem management and a better layout of ecological network. In this study, China's three typical urbanization agglomerations, Beijing-Tianjin-Hebei urban agglomeration (BTH), Yangtze River Delta urban agglomeration (YRD), and Pearl River Delta urban agglomeration (PRD), were selected as the study area. Spatiotemporal changes in ENs, the changing patterns, its eco-environment effects, and impacts of rapid urbanization were analyzed by environment indices, buffer analysis, and correlation analysis. The results showed a great lost in ENs from 2000 to 2015. Four patterns were seen in changing ENs: decomposition process (DP), internal change process (ICP), polycondensation process (PP), and external change process (ECP). ICP was dominated in YRD and PRD. ECP was the main pattern in core areas of BTH. The correlation analysis with YRD as the example showed that the changes in ENs had a certain impact on the eco-environment, especially in the 10-km buffer zone. The decrease of ENs was related to the increase of developed land, and the closer to the core area, the higher the correlation coefficient was. Reduction of ENs would slow down to a certain extent, when the agglomeration is in a higher urbanization stage. Different directions of restoration and optimization of ENs were proposed for the three urban agglomerations. The study will provide support for sustainable management and restoration and optimization of ENs for China's agglomerations.


Asunto(s)
Ecosistema , Urbanización , Beijing , China , Ciudades , Clima , Ríos
18.
Environ Sci Pollut Res Int ; 29(13): 19295-19308, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34713404

RESUMEN

The household sector has become the second-largest source of energy consumption and CO2 emissions in China. It is important to understand the trends and changing mechanisms of household energy-related CO2 emissions (HECEs) in different social stages for mitigating the impact of climate change. However, the existing trends in HECEs and whether they are congruent with the expectation that HECEs in later developed areas are lower than those in priority areas under the same economic level are unclear. Here, we compared the per capita HECEs (PHECEs) of urban agglomerations under the same economic standards and analyzed the causes of the comparative results. We find that (1) HECEs increased rapidly from 3.65 × 108 t to 12.42 × 108 t during 1995-2017, with an average annual growth rate of 14.19%; (2) urban agglomerations that developed earlier do not have higher PHECEs. The PHECEs of urban agglomerations with moderate and later development do not decrease under increased social, technological, and cognitive conditions; (3) carbon intensity (CI), energy intensity (EI), and per capita regional gross domestic product (PCG) have a positive impact on PHECEs, and the potential impact of EI on PHECEs reduction is greater; (4) the effects of CI, EI, and PCG on PHECEs in different urban agglomerations are various. However, these effects are similar within urban agglomerations. Our study provides a reference for reducing CO2 emissions in the household sector and for the green development of urban agglomerations and emphasizes that the growth of HECE at a reasonable level is necessary when technology does not meet sufficient constraints.


Asunto(s)
Dióxido de Carbono , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , China , Desarrollo Económico , Producto Interno Bruto , Ríos
19.
Front Cell Dev Biol ; 9: 697243, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34513833

RESUMEN

miRNAs are conserved short non-coding RNAs that play a role in the modulation of various biological pathways during tissue and organ morphogenesis. In this study, the function of miRNA-221-3p in tooth development, through its loss or gain in function was evaluated. A variety of techniques were utilized to evaluate detailed functional roles of miRNA-221-3p during odontogenesis, including in vitro tooth cultivation, renal capsule transplantation, in situ hybridization, real-time PCR, and immunohistochemistry. Two-day in vitro tooth cultivation at E13 identified altered cellular events, including cellular proliferation, apoptosis, adhesion, and cytoskeletal arrangement, with the loss and gain of miRNA-221-3p. qPCR analysis revealed alterations in gene expression of tooth-related signaling molecules, including ß-catenin, Bmp2, Bmp4, Fgf4, Ptch1, and Shh, when inhibited with miRNA-221-3p and mimic. Also, the inhibition of miRNA-221-3p demonstrated increased mesenchymal localizations of pSMAD1/5/8, alongside decreased expression patterns of Shh and Fgf4 within inner enamel epithelium (IEE) in E13 + 2 days in vitro cultivated teeth. Moreover, 1-week renal transplantation of in vitro cultivated teeth had smaller tooth size with reduced enamel and dentin matrices, along with increased cellular proliferation and Shh expression along the Hertwig epithelial root sheath (HERS), within the inhibitor group. Similarly, in 3-week renal calcified teeth, the overexpression of miRNA-221-3p did not affect tooth phenotype, while the loss of function resulted in long and slender teeth with short mesiodistal length. This study provides evidence that a suitable level of miRNA-221-3p is required for the modulation of major signaling pathways, including Wnt, Bmp, and Shh, during tooth morphogenesis.

20.
Plant Physiol Biochem ; 166: 849-856, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34229165

RESUMEN

γ-Aminobutyric acid (GABA), a signal molecule, is regarded as the intersection node of carbon and nitrogen metabolism, and its contributions to flavonoid metabolism in tea plant growth and development remain unclear. The correlation between the GABA shunt and flavonoid metabolism in tea plants is worth to explore. Secondary metabolites and their correlations with the taste of tea soup made from tea plants (Camellia sinensis) during different seasons were investigated. Related secondary metabolites and transcript profiles of genes encoding enzymes in the GABA shunt, flavonoid pathway and polyamine biosynthesis were measured throughout the tea plant growth seasons and after exogenous GABA applications. In addition, the abundance of differentially expressed proteins was quantified after treatments with or without exogenous GABA. The tea leaves showed the highest metabolite concentrations in spring season. CsGAD, CsGABAT, CsSPMS, CsODC, CsF3H and CsCHS were found to be important genes in the GABA and anthocyanin biosynthesis pathways. GABA and anthocyanin concentrations showed a positive correlation, to some extent, CsF3H and CsCHS played important roles in the GABA and anthocyanin biosynthesis.


Asunto(s)
Camellia sinensis , Camellia sinensis/metabolismo , Flavonoides , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , , Ácido gamma-Aminobutírico
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