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1.
Zhongguo Zhong Yao Za Zhi ; 48(3): 752-761, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-36872239

RESUMO

This study explores the effect of apigenin(APG), oxymatrine(OMT), and APG+OMT on the proliferation of non-small cell lung cancer cell lines and the underlying mechanisms. Cell counting kit-8(CCK-8) assay was used to detect the vitality of A549 and NCI-H1975 cells, and colony formation assay to evaluate the colony formation ability of the cells. EdU assay was employed to examine the proliferation of NCI-H1975 cells. RT-qPCR and Western blot were performed to detect the mRNA and protein expression of PLOD2. Molecular docking was carried out to explore the direct action ability and action sites between APG/OMT and PLOD2/EGFR. Western blot was used to study the expression of related proteins in EGFR pathway. The viability of A549 and NCI-H1975 cells was inhibited by APG and APG+OMT at 20, 40, and 80 µmol·L~(-1) in a dose-dependent manner. The colony formation ability of NCI-H1975 cells was significantly suppressed by APG and APG+OMT. The mRNA and protein expression of PLOD2 was significantly inhibited by APG and APG+OMT. In addition, APG and OMT had strong binding activity with PLOD2 and EGFR. In APG and APG+OMT groups, the expression of EGFR and proteins in its downstream signaling pathways was significantly down-regulated. It is concluded that APG in combination with OMT could inhibit non-small lung cancer, and the mechanism may be related to EGFR and its downstream signaling pathways. This study lays a new theoretical basis for the clinical treatment of non-small cell lung cancer with APG in combination with OMT and provides a reference for further research on the anti-tumor mechanism of APG in combination with OMT.


Assuntos
Alcaloides , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Apigenina , Simulação de Acoplamento Molecular , Quinolizinas , RNA Mensageiro , Receptores ErbB
2.
Environ Sci Technol ; 49(10): 5897-904, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25894303

RESUMO

The source region of the Yellow River, China, experienced degradation during the 1980s and 1990s, but effective ecological restoration projects have restored the alpine grassland ecosystem. The local government has taken action to restore the grassland area since 1996. Remote sensing monitoring results show an initial restoration of this alpine grassland ecosystem with the structural transformation of land cover from 2000 to 2009 as low- and high-coverage grassland recovered. From 2000 to 2009, the low-coverage grassland area expanded by over 25% and the bare soil area decreased by approximately 15%. To examine the relationship between ecological structure and function, surface temperature (Ts) and evapotranspiration (ET) levels were estimated to study the dynamics of the hydro-heat pattern. The results show a turning point in approximately the year 2000 from a declining ET to a rising ET, eventually reaching the 1990 level of approximately 1.5 cm/day. We conclude that grassland coverage expansion has improved the regional hydrologic cycle as a consequence of ecological restoration. Thus, we suggest that long-term restoration and monitoring efforts would help maintain the climatic adjustment functions of this alpine grassland ecosystem.


Assuntos
Mudança Climática , Clima , Ecossistema , Recuperação e Remediação Ambiental , Poaceae , China , Ecologia , Rios , Solo , Temperatura
3.
Front Plant Sci ; 15: 1352834, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590743

RESUMO

Alpine wetland degradation threatens riparian biodiversity and ecological balance. Our study, conducted in July 2020 along the northern and eastern shores of Qinghai Lake, seeks to unravel the impacts of such degradation on plant species dominance and ecological niches, using advanced network analysis methods to explore the dynamics and survival strategies of plant species. We applied a space-to-time method to delineate three wetland degradation stage: a healthy swamp wetland, a slightly degraded wet meadow, and a degraded dry meadow. Six representative sampling points were chosen. At each point, three sample lines were randomly established, radiating outward from the center of the lake wetland, with each stage of degradation meticulously examined through three replicates to assess the plant communities in terms of species composition, plant height, coverage, and abundance. The results indicated: Species such as Kobresia tibetica and Leymus secalinus exhibit remarkable abundance across various stages of wetland degradation, indicating a robust tolerance to these conditions. This observation, coupled with the complexity of plant community structures in degrading wetlands, suggests that such intricacy cannot be solely attributed to the dominance of particular species. Instead, it is the result of a diverse array of species adapting to fluctuating water levels, which promotes increased species richness. Despite the prominence of species that exhibit rapid growth and reproduction, the ecological significance of less abundant species in contributing to the community's complexity is also notable. Changes in habitat conditions due to wetland degradation facilitate both competitive and cooperative interactions among species, highlighting the dynamic nature of these ecosystems. Our analysis shows no significant linear relationship between the ecological niche overlap values and niche widths of plant species. However, the strategies employed by dominant species for competition and resource acquisition, as observed in the ecological niche overlap networks, underscore the adaptive capacity of plant communities. These insights underscore the need for tailored restoration strategies to conserve the biodiversity of alpine lake riparian ecosystems. This research not only sheds light on the resilience and adaptability of ecosystems in the Qinghai-Tibetan Plateau but also offers valuable lessons for the conservation of similar habitats worldwide. Our findings underscore the need for tailored restoration strategies to conserve the biodiversity of alpine lake riparian ecosystems. This research not only sheds light on the resilience and adaptability of ecosystems in the Qinghai-Tibetan Plateau but also offers valuable lessons for the conservation of similar habitats worldwide.

4.
J Ethnopharmacol ; 319(Pt 3): 117364, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38380576

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: As a traditional Chinese medicine, Artemisia argyi has been used medicinally and eaten for more than 2000 years in China. It is widely reported in treating inflammatory diseases such as eczema, dermatitis, arthritis, allergic asthma and colitis. Although several studies claim that its volatile oil and organic reagent extracts have certain anti-inflammatory effects, the water-soluble fractions and molecular mechanisms have not been studied. AIM OF THE STUDY: To evaluate the therapeutic effect of A. argyi water extract (AAWE) on lipopolysaccharide (LPS)-induced inflammatory responses and to identify the most effective water-soluble subfractions. Moreover, the relevant pharmacological and molecular mechanisms by which the active subfraction mitigates inflammation were further investigated. MATERIALS AND METHODS: Firstly, RAW 264.7 cells stimulated with LPS were treated with AAWE (50, 100, and 200 µg/mL) or the water-soluble subfractions separated by D101 macroporous resin (AAWE1-AAWE4, 100 µg/mL), and NO production and mRNA levels of inflammatory genes were evaluated to determine the most effective water-soluble subfractions. Secondly, the chemical components of the active subfraction (AAWE4) were analyzed by UPLC-QTOF-MS. Thirdly, transcriptome and network pharmacology analysis, RT-qPCR and Western blotting assays were conducted to explore the underlying anti-inflammatory mechanism and active compounds of AAWE4. Subsequently, the binding ability of the potential active components in AAWE4 to the core targets was further determined by molecular docking. Eventually, the in vivo anti-inflammatory activity of AAWE4 (1.17, 2.34 and 4.68 g/kg, administered per day for 7 d) was evaluated in mice with LPS-induced systemic inflammation. RESULTS: In this study, AAWE showed excellent anti-inflammatory effects, and its water-soluble subfraction AAWE4 exhibited the strongest inhibitory effect on NO concentration and inflammatory gene mRNA expression after LPS stimulation, indicating that it was the most effective subfraction. Thereafter, four main compounds in AAWE4 were confirmed or tentatively identified by UPLC-QTOF-MS, including three flavonoid glycosides and one phenolic acid. Furthermore, the transcriptome and network pharmacology analysis showed that AAWE4 inhibited inflammation via multiple pathways and multiple targets. Based on the RT-qPCR and Western blotting results, AAWE4 downregulated not only the p38, PI3K, CCL5, MMP9, AP-1, and BCL3 mRNA expression levels activated by LPS but also their upstream and downstream protein expression levels and protein phosphorylation (p-AKT/AKT, p-p38/p38, p-ERK/ERK, p-JNK/JNK). Moreover, four identified compounds (isochlorogenic acid A, vicenin-2, schaftoside and isoschaftoside) could significantly inhibit NO content and the overexpression of inflammatory factors TNF-α, IL-1ß, iNOS and COX-2 mRNA induced by LPS, and the molecular docking confirmed the high binding activity of four active compounds with selected core targets (p38, AKT1, MMP9, and CCL5). In addition, the mRNA expression and immunohistochemical analysis showed that AAWE44 could inhibit lung inflammation via multiple pathways and multiple targets in vivo. CONCLUSIONS: The findings of this study suggest that the water-soluble subfraction AAWE4 from A. argyi ameliorated the inflammation caused by LPS through multiple pathways and multiple targets in vitro and in vivo, providing scientific support for the medicinal use of A. argyi. Importantly, it shows that the A. argyi subfraction AAWE4 can be developed as an anti-inflammatory drug.


Assuntos
Artemisia , Lipopolissacarídeos , Animais , Camundongos , Lipopolissacarídeos/toxicidade , Extratos Vegetais/farmacologia , Metaloproteinase 9 da Matriz , NF-kappa B/metabolismo , Água , Artemisia/química , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-akt , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/química , RNA Mensageiro
5.
Phytochemistry ; 223: 114120, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705265

RESUMO

Eleven previously undescribed sesquiterpenoids (8-18), one undescribed jasmonic acid derivative (35) and 28 known compounds were isolated from the leaves of Artemisia stolonifera. Undescribed compounds with their absolute configurations were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction and ECD calculation. Compound 8 was identified as a rare sesquiterpenoid featuring a rearranged 5/8 bicyclic ring system, whereas compound 17 was found to be an unprecedented monocyclic sesquiterpenoid with methyl rearrangement. Evaluation of biological activity showed that compounds 1-5 and 7 displayed cytotoxicity against six tumor cells. In the meantime, compounds 11, 12, 18 and 35 exhibited inhibitory effects against LPS-stimulated NO production in RAW 264.7 macrophage cells and reduced the transcription of IL-6 and IL-1ß in a dose-dependent manner at 25, 50 and 100 µM. Moreover, the anti-inflammatory-based network pharmacology and molecular docking analyses revealed potential target proteins of 11, 12, 18 and 35.


Assuntos
Anti-Inflamatórios , Artemisia , Ciclopentanos , Óxido Nítrico , Oxilipinas , Sesquiterpenos , Artemisia/química , Camundongos , Oxilipinas/farmacologia , Oxilipinas/química , Oxilipinas/isolamento & purificação , Animais , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Ciclopentanos/química , Ciclopentanos/farmacologia , Ciclopentanos/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Estrutura Molecular , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Humanos , Relação Dose-Resposta a Droga , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Folhas de Planta/química , Ensaios de Seleção de Medicamentos Antitumorais
6.
Ecology ; 104(4): e3973, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36688902

RESUMO

Understanding the spatial scaling of population stability is critical for informing conservation strategies. A recently proposed metric for quantifying how population stability varies across scales is the invariability-area relationship (IAR), but the underlying drivers shaping IARs remain unclear. Using 15-year records of 249 bird species in 1035 survey transects in North America, we derived the IAR for each species by calculating population temporal invariability at different spatial scales (i.e., number of routes) and investigated how species IARs were influenced by functional traits and environmental factors. We found that species with faster life history traits and reduced flight efficiency had higher IAR intercepts (i.e., locally more stable), whereas migratory species exhibited higher IAR slopes (i.e., a faster gain of stability with increasing spatial scale). In addition, spatial correlation in temperature and vegetation structure synchronized bird population dynamics over space and thus decreased IAR slopes. By demonstrating the joint influence of functional traits and environmental factors on bird population stability across scales, our results highlight the need for dynamic conservation strategies tailored to particular types of species in an era of global environmental changes.


Assuntos
Aves , Animais , América do Norte , Dinâmica Populacional
7.
Talanta ; 261: 124600, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37216890

RESUMO

Reliable H2O2 sensors for in situ cellular monitoring under drug stimulation can be developed as a powerful and versatile tool for drug evaluation. Herein, a novel electrochemical biosensor capable of detecting and quantifying H2O2 was fabricated by graphene and shape-controlled gold nanostructures. With the help of polyelectrolytes, gold exhibited hierarchical flower-like nanostructures. This kind of nanozyme material exhibited a prominent electrochemical response for H2O2. Electrocatalytic activity for H2O2 reduction with high sensitivity (5.07◊10-4 mA µmol L-1 cm-2) and good detection capability (the lowest detection limit is 4.5 µmol L-1 (S/N = 3)) were achieved. This electrochemical biosensor was successfully used to measure the concentration of H2O2 released from HepG2 hepatoma cells. Ascorbic acid (AA) and Camellia nitidissima Chi saponins (CNCS) were selected as model drugs, and their anticancer activities were compared by in situ monitoring of H2O2. Interestingly, the electrochemical sensor showed remarkable sensitivity, accuracy, and rapidity compared with the traditional enzymatic detection kit. In brief, the as-synthesized nanostructured H2O2 sensors can be applied to assess the antitumor properties of candidate drugs and inspire developments for personalized health care monitoring and cancer treatment.


Assuntos
Antineoplásicos , Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Grafite/química , Peróxido de Hidrogênio , Nanopartículas Metálicas/química , Avaliação de Medicamentos , Técnicas Eletroquímicas , Ouro/química , Antineoplásicos/farmacologia
8.
Sci Total Environ ; 877: 162773, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36933739

RESUMO

Nervous system disease (NSD) is a global health burden with increasing prevalence in the last 30 years. There is evidence that greenness can improve nervous system health through a variety of mechanisms; however, the evidence is inconsistent. In the present systematic review and meta-analysis, we examined the relationship between greenness exposure and NSD outcomes. Studies on the relationship between greenness and NSD health outcomes published till July 2022 were searched in PubMed, Cochrane, Embase, Scopus, and Web of Science. In addition, we searched the cited literature and updated our search on Jan 20, 2023, to identify any new studies. We included human epidemiological studies that assess the association of greenness exposure with the risk of NSD. Greenness exposure was measured using NDVI (the normalized difference vegetation index) and the outcome was the mortality or morbidity of NSD. The pooled relative risks (RRs) were estimated using a random effects model. Of 2059 identified studies, 15 studies were included in our quantitative evaluation, in which 11 studies found a significant inverse relationship between the risk of NSD mortality or incidence/prevalence and an increase in surrounding greenness. The pooled RRs for cerebrovascular diseases (CBVD), neurodegenerative diseases (ND), and stroke mortality were 0.98 (95 % CI: 0.97, 1.00), 0.98 (95 % CI: 0.98, 0.99), and 0.96 (95 % CI: 0.93, 1.00), respectively. The pooled RRs for PD incidence and stroke prevalence/incidence were 0.89 (95 % CI: 0.78, 1.02) and 0.98 (95 % CI: 0.97, 0.99), respectively. The confidence of evidence for ND mortality, stroke mortality, and stroke prevalence/incidence was downgraded to "low", while CBVD mortality and PD incidence were downgraded to "very low" due to inconsistency. We found no evidence of publication bias and the sensitivity analysis results of all subgroups are robust except for the stroke mortality subgroup. This is the first comprehensive meta-analysis of greenness exposure and NSD outcomes in which an inverse relationship was observed. It is necessary to conduct further research to ascertain the role greenness exposure plays in various NSDs and the management of greenness should be considered a public health strategy.


Assuntos
Transtornos Cerebrovasculares , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/epidemiologia , Incidência , Prevalência
9.
Microorganisms ; 10(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35456816

RESUMO

Soil bacteria are important components of forest ecosystems, there compostion structure and functions are sensitive to environmental conditions along elevation gradients. Using 16S rRNA gene amplicon sequencing followed by FAPROTAX function prediction, we examined the diversity, composition, and functional potentials of soil bacterial communities at three sites at elevations of 1400 m, 1600 m, and 2200 m in a temperate forest. We showed that microbial taxonomic composition did not change with elevation (p = 0.311), though soil bacterial α-diversities did. Proteobacteria, Acidobacteria, Actinobacteria, and Verrucomicrobia were abundant phyla in almost all soil samples, while Nitrospirae, closely associated with soil nitrogen cycling, was the fourth most abundant phylum in soils at 2200 m. Chemoheterotrophy and aerobic chemoheterotrophy were the two most abundant functions performed in soils at 1400 m and 1600 m, while nitrification (25.59% on average) and aerobic nitrite oxidation (19.38% on average) were higher in soils at 2200 m. Soil CO2 effluxes decreased (p < 0.050) with increasing elevation, while they were positively correlated (r = 0.55, p = 0.035) with the abundances of bacterial functional groups associated with carbon degradation. Moreover, bacterial functional composition, rather than taxonomic composition, was significantly associated with soil CO2 effluxes, suggesting a decoupling of taxonomy and function, with the latter being a better predictor of ecosystem functions. Annual temperature, annual precipitation, and pH shaped (p < 0.050) both bacterial taxonomic and functional communities. By establishing linkages between bacterial taxonomic communities, abundances of bacterial functional groups, and soil CO2 fluxes, we provide novel insights into how soil bacterial communities could serve as potential proxies of ecosystem functions.

10.
Front Nutr ; 9: 1014414, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386893

RESUMO

As a medicine-food homology (MFH) plant, golden-flowered tea (Camellia nitidissima Chi, CNC) has many different pharmacologic activities and is known as "the queen of the tea family" and "the Panda of the Plant world". Several studies have revealed the pharmacologic effects of CNC crude extract, including anti-tumor, anti-oxidative and hepatoprotective activity. However, there are few studies on the anti-tumor active fractions and components of CNC, yet the underlying mechanism has not been investigated. Thus, we sought to verify the anti-non-small cell lung cancer (NSCLC) effects of four active fractions of CNC. Firstly, we determined the pharmacodynamic material basis of the four active fractions of CNC (Camellia. leave. saponins, Camellia. leave. polyphenols, Camellia. flower. saponins, Camellia. flower. polyphenols) by UPLC-Q-TOF-MS/MS and confirmed the differences in their specific compound contents. Then, MTT, colony formation assay and EdU incorporation assay confirmed that all fractions of CNC exhibit significant inhibitory on NSCLC, especially the Camellia. leave. saponins (CLS) fraction on EGFR mutated NSCLC cell lines. Moreover, transcriptome analysis revealed that the inhibition of NSCLC cell growth by CLS may be via three pathways, including "Cytokine-cytokine receptor interaction," "PI3K-Akt signaling pathway" and "MAPK signaling pathway." Subsequently, quantitative real-time PCR (RT-qPCR) and Western blot (WB) revealed TGFB2, INHBB, PIK3R3, ITGB8, TrkB and CACNA1D as the critical targets for the anti-tumor effects of CLS in vitro. Finally, the xenograft models confirmed that CLS treatment effectively suppressed tumor growth, and the key targets were also verified in vivo. These observations suggest that golden-flowered tea could be developed as a functional tea drink with anti-cancer ability, providing an essential molecular mechanism foundation for MFH medicine treating NSCLC.

11.
Animals (Basel) ; 11(12)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34944154

RESUMO

The high-altitude ecosystem of the Tibetan Plateau in China is a biodiversity hotspot that provides unique habitats for endemic and relict species along an altitudinal gradient at the eastern edge. Acquiring biodiversity information in this area, where the average altitude is over 4000 m, has been difficult but has been aided by recent developments in non-invasive technology, including infrared-triggered camera trapping. We used camera trapping to acquire a substantial number of photographic wildlife records in Wolong National Nature Reserve, Sichuan, China, from 2013 to 2016. We collected information of the habitat surrounding the observation sites, resulting in a dataset covering 37 species and 12 environmental factors. We performed a multivariate statistical analysis to discern the dominant environmental factors and cluster the mammals and birds of the ecosystem in order to examine environmental factors contributing to the species' relative abundance. Species were generalized into three main types, i.e., cold-resistant, phyllophilic, and thermophilic, according to the identified key environmental drivers (i.e., temperature and vegetation) for their abundances. The mammal species with the highest relative abundance were bharal (Pseudois nayaur), Moupin pika (Ochotona thibetana), and Himalayan marmot (Marmota himalayana). The bird species with highest relative abundance were snow partridge (Lerwa lerwa), plain mountain finch (Leucosticte nemoricola), Chinese monal (Lophophorus lhuysii), and alpine accentor (Prunella collaris).

12.
Int J Biol Macromol ; 164: 4095-4103, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32896560

RESUMO

The development of porous carbon materials from sustainable natural sources is an attractive topic in the field of energy storage materials. This study proposed the production of nitrogen-doped porous carbon (NPC) materials from the renewable cellulose nanocrystal (CNC) as carbon source and water-soluble urea as nitrogen source without any external activation. The liquid compounding treatment and subsequent carbonization provided the NPC materials a uniform and stable N-doping (7.4% nitrogen content), high specific surface area (366.5 m2/g) and various superior electrochemical properties. The fabricated NPC sample (CU-3, with the weight ratio of 1:10 for CNC and urea) exhibited a high specific capacitance of 570.6 F/g at a current density load of 1 A/g and good cycling stability (91.2% capacitance retention after 1000 cycles at a current density of 10 A/g) in the 6 M KOH electrolyte. Applying this NPC material as the electrode component in the assembled symmetric supercapacitor demonstrated the promising electrochemical stability with the specific capacitances of 88.2 F/g at the current density of 1 A/g and capacitance retention of 99.8% after 5000 cycles. The developed N-doped porous carbon material from CNCs and urea is expected to be a sustainable electrode component for the supercapacitor materials.


Assuntos
Carbono/química , Celulose/química , Capacitância Elétrica , Nanopartículas/química , Nitrogênio/química , Ureia/química , Fenômenos Químicos , Eletroquímica , Nanopartículas/ultraestrutura , Porosidade , Difração de Raios X
13.
ACS Appl Mater Interfaces ; 11(3): 2840-2848, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30584765

RESUMO

A new molecularly imprinted SiO2 (MISiO2) film on the surface of indium tin oxide (ITO) electrode was prepared by the sol-gel method and was then applied successfully in the electrochemical chiral recognition of tryptophan (Trp) isomers. Owing to the high chemical stability, excellent rigidity, and low cost, the resultant sol-gel SiO2 is a good matrix material for molecular imprinting. Nonionic surfactant cicosaethylene glycol hexadecyl ether (Brij58) arranged directionally on the surface of the hydrophobic ITO electrode possesses a large amount of oxygen-containing functional groups and may induce the accumulation of template molecules (L-Trp) on the surface of ITO, resulting in L-MISiO2/ITO after the removal of L-Trp templates by calcination. The characterizations of the L-MISiO2/ITO reveal that the L-Trp templates could be successfully removed from the matrix, producing complementary cavities within the L-MISiO2/ITO. The resultant L-MISiO2/ITO exhibits greatly higher affinity toward L-Trp than D-Trp due to the three-point interaction mechanism, and therefore it exhibits good chiral recognition ability for the Trp isomers. In addition, the as-prepared L-MISiO2/ITO or D-MISiO2/ITO (D-Trp as the templates) can predict the ratio of L- and D-isomers in racemic mixture. Last, the MISiO2 films exhibited quick binding kinetics and good recognition reproducibility.

14.
Sci Total Environ ; 647: 1080-1087, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30180316

RESUMO

Land-climate interactions are driven by causal relations that are difficult to ascertain given the complexity and high dimensionality of the systems. Many methods of statistical and mechanistic models exist to identify and quantify the causality in such highly-interacting systems. Recent advances in remote sensing development allowed people to investigate the land-climate interaction with spatially and temporally continuous data. In this study, we present a new approach to measure how climatic factors interact with each other under land cover change. The quantification method is based on the correlation analysis of the different order derivatives, with the canonical mathematical definitions developed from the theories of system dynamics and practices of the macroscopic observations. We examined the causal relationship between the interacting variables on both spatial and temporal dimensions based on macroscopic observations of land cover change and surface climatic factors through a comparative study in the different grassland ecosystems of China. The results suggested that the interaction of land-climate could be used to explain the temporal lag effect in the comparison of the three grassland ecosystems. Significant spatial correlations between the vegetation and the climatic factors confirmed feedback mechanisms described in the theories of eco-climatology, while the uncertain temporal synchronicity reflects the causality among the key indicators. This has been rarely addressed before. Our research show that spatial correlations and the temporal synchronicity among key indicators of the land surface and climatic factors can be explained by a novel method of causality quantification using derivative analysis.

15.
Environ Int ; 108: 285-298, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28918369

RESUMO

The hydropower capacity of China ranks first in the world and accounts for approximately 20% of the total energy production in the country. While hydropower has substantially contributed to meeting China's renewable energy targets and providing clean energy to rural areas, the development of hydropower in China has been met with significant controversy. Ecologically, hydro projects alter the landscape, with potential impacts to the country's aquatic biodiversity. Over the past four decades in China, various mainstream opinions and misunderstandings have been presented concerning how to alleviate the negative impacts of hydro projects on aquatic ecosystems. This article reviews research concerning potential mitigation measures to enhance aquatic biodiversity conservation in hydro projects in China. Based on the academic attention such research has attracted, three technical measures for aquatic biodiversity conservation are considered: (1) fish passages, (2) restocking efforts and (3) river and lake renovations. This article provides a historical comparison of these three practices in China to demonstrate the advantages and disadvantages of each method. The article also reviews the relevant legislation, regulations and technical guidelines concerning China's hydro projects dating back to 1979. The dynamics in research, publications, and patents concerning these three mitigation measures are summarized to demonstrate their technological developments in the context of legislative and policy advances. Data were gathered through the China Knowledge Resource Integrated Database and the State Intellectual Property Office of the People's Republic of China. Based on the analysis provided, the article recommends an expansion of China's environmental certification system for hydro projects, more robust regional legislation to bolster the national framework, the cooperation between upstream and downstream conservation mechanisms, and better monitoring to determine the efficacy of mitigation measures.


Assuntos
Biodiversidade , Conservação dos Recursos Hídricos , Centrais Elétricas , Animais , China , Ecossistema , Plantas , Rios
16.
Environ Int ; 85: 46-53, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26318514

RESUMO

The balance between economic development and ecological conservation in China has become a critical issue in recent decades. Ecological impact assessment (EcoIA) was established beginning in the 1980s as a component of environmental impact assessment (EIA) that focuses specifically on human-related changes in ecosystem structure and function. EcoIA has since been widely applied throughout the country with continuous refinements in theory and practice. As compared to EIA, EcoIA is often performed at a larger scale in the long-term, and thus requires more advanced tools and techniques to quantify and assess. This paper reviews the development of EcoIA over the past 30years in China, with specific consideration given to refinements in legislation and methodology. Three stages in the development of EcoIA in China are identified, along with their achievements and limitations. Supplementing this qualitative analysis, the paper also provides a quantitative bibliometrics review of academic publications concerning EcoIA in China over the three identified stages. Lastly, general trends in the development of EcoIA are summarized with the aim of conveying potential future trajectories. This review is intended to introduce the EcoIA system to scholars interested in the growing field of environmental management in China.


Assuntos
Conservação dos Recursos Naturais/métodos , Desenvolvimento Econômico , Ecossistema , Política Ambiental/legislação & jurisprudência , China , Conservação dos Recursos Naturais/legislação & jurisprudência , Ecologia , Humanos
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