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1.
Sci Total Environ ; 916: 170071, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38242465

RESUMO

The Belt and Road Initiative (BRI) is an open platform for international cooperation proposed by China to promote common global development and prosperity. The BRI can promote the optimal allocation of resources and promote in-depth cooperation in international trade. Meanwhile, it can establish a green supply chain cooperation network to help BRI countries achieve green transformation. BRI has made a notable contribution to the rapid growth of cross-border trade. However, it has also brought environmental impacts. Given that little attention has been paid to the trade-embodied particulate matter 2.5 related human health impacts (PM2.5-HHI) throughout the BRI, this study accounts for and traces the embodied PM2.5-HHI flows between the BRI countries and non-Belt and Road Initiative (non-BRI) countries. Moreover, this study also uncovers the critical socioeconomic drivers of PM2.5-HHI changes in BRI countries during 1990-2015, based on the multi-regional input-output based structural decomposition analysis (MRIO-SDA). Results show that, firstly, BRI countries had significantly increased their economic added value by exporting products to the non-BRI countries. They also have brought PM2.5-HHI to themselves. Secondly, the final demand of BRI countries was the largest potential driving force of PM2.5-HHI of BRI countries. Thirdly, the emission intensity change of BRI is the key socioeconomic factor for reducing PM2.5-HHI. While per capita final demand level change of BRI and production structure change of non-BRI are the key socioeconomic factors for increasing PM2.5-HHI. The study's findings on the one hand can help reduce the PM2.5-HHI and impacts of environmental pollution of BRI countries from a global perspective by providing scientific support. On the other hand, they can help provide relevant policy recommendations for the green transformation of BRI and the construction of green BRI.


Assuntos
Comércio , Internacionalidade , Humanos , China , Meio Ambiente , Material Particulado/análise , Desenvolvimento Econômico , Dióxido de Carbono/análise
2.
Environ Sci Technol ; 57(48): 19690-19701, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37930250

RESUMO

Decoupling global economic growth from carbon emissions is essential for mitigating global climate change while maintaining continuous economic growth. Traditional production-side decoupling analysis alone is insufficient to capture the decoupling status between carbon emissions and the value added throughout global supply chains. This study investigates the decoupling status between value added and greenhouse gas (GHG) emissions during 1995-2019 from consumption and income perspectives. We find that the decoupling statuses of 17 regions (especially Russia, Australia, and Malta) show significant differences across multiple perspectives. For example, Malta's direct GHG emissions decreased with its GDP growth from a production perspective (i.e., achieved strong decoupling). However, its consumption-based GHG emissions increased with the growth of consumption-based value added (i.e., expansive negative decoupling). Moreover, most international pairs have not yet achieved strong decoupling from consumption and income perspectives. International multilateral cooperation is crucial for decoupling global GHG emissions from economic growth across global supply chains. This study provides insights into the decoupling between embodied GHG emissions and value added from consumption and income perspectives. The findings of this study can complement existing policies on global GHG emission mitigation and sustainable development.


Assuntos
Efeito Estufa , Gases de Efeito Estufa , Carbono , Dióxido de Carbono/análise , Desenvolvimento Econômico , China
3.
Nat Commun ; 14(1): 5458, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673896

RESUMO

Current induced spin-orbit torque (SOT) holds great promise for next generation magnetic-memory technology. Field-free SOT switching of perpendicular magnetization requires the breaking of in-plane symmetry, which can be artificially introduced by external magnetic field, exchange coupling or device asymmetry. Recently it has been shown that the exploitation of inherent crystal symmetry offers a simple and potentially efficient route towards field-free switching. However, applying this approach to the benchmark SOT materials such as ferromagnets and heavy metals is challenging. Here, we present a strategy to break the in-plane symmetry of Pt/Co heterostructures by designing the orientation of Burgers vectors of dislocations. We show that the lattice of Pt/Co is tilted by about 1.2° when the Burgers vector has an out-of-plane component. Consequently, a tilted magnetic easy axis is induced and can be tuned from nearly in-plane to out-of-plane, enabling the field-free SOT switching of perpendicular magnetization components at room temperature with a relatively low current density (~1011 A/m2) and excellent stability (> 104 cycles). This strategy is expected to be applicable to engineer a wide range of symmetry-related functionalities for future electronic and magnetic devices.

4.
Adv Sci (Weinh) ; 10(8): e2206203, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36703616

RESUMO

The anomalous Hall effect (AHE) is a quantum coherent transport phenomenon that conventionally vanishes at elevated temperatures because of thermal dephasing. Therefore, it is puzzling that the AHE can survive in heavy metal (HM)/antiferromagnetic (AFM) insulator (AFMI) heterostructures at high temperatures yet disappears at low temperatures. In this paper, an unconventional high-temperature AHE in HM/AFMI is observed only around the Néel temperature of AFM, with large anomalous Hall resistivity up to 40 nΩ cm is reported. This mechanism is attributed to the emergence of a noncollinear AFM spin texture with a non-zero net topological charge. Atomistic spin dynamics simulation shows that such a unique spin texture can be stabilized by the subtle interplay among the collinear AFM exchange coupling, interfacial Dyzaloshinski-Moriya interaction, thermal fluctuation, and bias magnetic field.

5.
Environ Technol ; 44(21): 3263-3280, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35306978

RESUMO

A new porous solid base catalyst was prepared using dewatered paper sludge and successfully employed to produce biodiesel from soybean oil. The as-prepared catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transforms infrared spectroscopy, X-ray photoelectron spectroscopy, thermal gravity/differential thermal gravity analysis, Brunauer-Emmet-Teller analysis, and CO2-temperature programmed analysis. The results showed that the formation of CaO and uniformly distributed porous structure should account for the high catalytic activity of the as-prepared catalyst. The optimum reaction conditions were observed at 180 ℃, 8 wt.% catalyst/oil weight ratio, 16:1 methanol/oil molar ratio, and 300 min reaction time with 91.6% biodiesel yield. After being used several times and recycled, the regenerated catalyst still exhibited effective catalytic activity without apparent deactivation. The kinetic study confirmed that the experimental data satisfied with Pseudo-first-order kinetic model controlled by reaction temperature and catalyst/oil weight ratio. The reaction activation energy was 24.98 kJ/mol. The change of enthalpy ΔH (14.98 kJ/mol), entropy ΔS (-208.57 J/mol/K), and Gibbs free energy ΔG (109.46 kJ/mol) indicated that the transesterification reaction catalyzed by the dewatered paper sludge-derived catalyst is endothermic, endergonic, and non-spontaneous. Our research finding indicated that the CaO-based catalyst derived from dewatered paper sludge was an economically promising and eco-friendly solid base catalyst for biodiesel production.


Assuntos
Biocombustíveis , Esgotos , Biocombustíveis/análise , Cinética , Porosidade , Termodinâmica , Catálise , Esterificação , Óleos de Plantas/química
6.
Nanoscale ; 14(38): 14046-14051, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36124916

RESUMO

Ferroelectric nanoislands have attracted intensive research interest due to their size effect induced exotic physical properties and potential applications in non-volatile ferroelectric memories. However, the self-assembly growth of highly ordered ferroelectric nanoisland arrays is still a challenge. Here, by patterning a LaAlO3 substrate with etched nanocavities to provide preferential nucleation sites, highly ordered self-assembled BiFeO3 nanoisland arrays with robust ferroelectric topological quad-domain configurations were achieved. From the thermodynamic and kinetic perspectives, three factors are critical for achieving highly ordered self-assembled nanoisland arrays, that is, preferential nucleation sites, an appropriate relationship between the surface energy and the interface energy, and the growth rate difference of films. This approach can also be employed for the self-assembly growth of nanoisland arrays in other ferroelectric materials, which facilitates the design of ferroelectric nanostructure-based nanodevices.

7.
Water Res ; 223: 118980, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987035

RESUMO

Existing studies on the virtual scarce water flows within the water-energy context focus on water quantity while largely ignoring water quality. This study improves the quantification method of scarce water uses by considering both blue water (representing water quantity) and grey water (indicating water quality). Based on a scarce-water extended multi-regional input-output model, we investigate the virtual scarce water flows driven by energy demand across 31 Chinese regions in 2012 and 2017. The results show that considering water quality provides new insights into the patterns of interregional flows of virtual scarce water driven by energy demand. The virtual integrated scarce water (VISW) flows, which consider both water quantity and quality, are 5 times the volume of virtual quantity-based scarce water (VQSW) flows. Moreover, certain regions (e.g., Hebei) are recognized as net VISW exporters, but are net importers in terms of VQSW. There are significant differences in the critical interregional pairs identified based on net VISW flows (e.g., Shandong-Zhejiang, and Shandong-Guangdong) and net VQSW flows (e.g., Heilongjiang-Guangdong, and Liaoning-Shaanxi). To reduce water scarcity based on the combined effect of both quantity and quality, the critical VISW interregional pairs should enhance cooperation through compensation payments and interregional technology transfer. This study highlights the importance of water quality in the assessment of virtual scarce water uses. Employing virtual scarce water as a policy tool to mitigate water scarcity might fail without the consideration of water quality.


Assuntos
Qualidade da Água , Abastecimento de Água , China
8.
Adv Mater ; 34(24): e2202181, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35405769

RESUMO

Multiplexing physical dimensions to realize multidimensional storage in a single material has been a goal to increase storage density and data security. Multidimensional storage is only achieved in optical storage material (OSM) by far. Poly(vinylidene fluoride) (PVDF), a semicrystalline polymer, is widely studied as a candidate for ferroelectric random access (FeRAM). Herein, the atomic force microscopy (AFM)-based infrared spectroscopy techniqueis used to induce multilevel phase transformations in PVDF ultrathin film on nanometric scales and for writing/readout of IR signals. An optical/ferroelectric multiplexing PVDF memory, where information can be coded with independent four-level optical IR and bilevel ferroelectric signals, is demonstrated. High data security and a storage density up to 180 GBit in.-2 are achieved simultaneously. Owing to the different critical temperature for phase transformation (optical data, <167 °C) and polarization switching (ferroelectric data, <100 °C), the multiplexing memory can function both as optical read-only memory and FeRAM. This work expands material supporting physical dimensions multiplexing beyond OSM for the first time, opening up new opportunities for future high-capacity, multifunctional nano-memory. The strategy proposed here enables on-demand and tunable programming on IR waves, offering prospects for fabrication of active nano-optical devices.

9.
Sci Total Environ ; 830: 154787, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35346699

RESUMO

The sustainability of the chemical industry is crucial for achieving global sustainable production. The sustainability performance of global chemical industry is influenced by many issues synergistically and has not been fully quantified. Systematic analysis from multiple perspectives, such as resource savings, economic growth, and environmental improvement, is urgently needed to support effective macro-policy decisions. This study quantifies the variation trend of the sustainability of the global chemical industry during 2004-2014 and identifies the driving forces under the framework of green total factor productivity (GTFP). Results show that most developed countries performed efficiently (with GTFP values equal to 1) in sustainable production of the chemical industry, while the least developed countries usually performed inefficiently (with GTFP values lower than 1). Notably, a polarization of sustainability in the chemical industry has been confirmed among countries with different production capacities. From 2004 to 2014, the sustainability performance of the global chemical industry has generally improved. It was mainly driven by technological progress (resulting from independent technological innovation) rather than efficiency catching-up (derived from technological learning). Furthermore, technological progress was manifested mainly as the improvement in CO2 reduction performance and capital saving performance, while technological learning was manifested mainly as the improvement in labor saving performance. Based on the conclusions of this study, the international world is suggested to take action to strengthen international technology cooperation, and governments should make prioritized and focused policies to effectively promote the sustainability of global chemical industry.


Assuntos
Indústria Química , Desenvolvimento Econômico , China , Eficiência , Políticas , Tecnologia
10.
Environ Sci Pollut Res Int ; 29(16): 23520-23544, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34807380

RESUMO

The Middle Route (MR) of the South-to-North Water Diversion Project (SNWDP) of China is one of the world's largest inter-basin water diversion projects. As an important source of drinking water in North China, its water quality safety determines the success or failure of a sizable water supply. At present, there is a lack of in-depth and systematic understanding of the interaction between hydrodynamics and the water environment as well as water ecological processes in the main canal at the early stages of operation. It is not currently possible to accurately predict water quality and algae status at the early stage of canal ecosystem succession. Change trends and distribution characteristics of the main water ecological environment elements in the main canal at the early MR stage are analyzed in this study. The main factors influencing algae are investigated by principal component analysis (PCA) to characterize the water quality and algae transport distribution in the main MR canal under the complex multi-sluice joint dispatching conditions. The relationship between environmental factors, hydrodynamic, water quality, and algae in the coupled canal-sluice system in the SNWDP MR is determined. Algae distributions under different water transmission conditions in a typical canal section are predicted accordingly. CODMn and algal density in the main canal are shown to increase from south to north along the canal. DO decreases from south to north; other water quality indexes do not significantly differ from north to south. Algal density along the canal differs to the greatest extent in summer, followed by spring and autumn, and is the weakest in winter. The predicted algae densities in the main canal under different water conveying conditions show that single sluice control and strong water flow from Taocha Head Section increase the flow velocity after passing through the sluice with a fixed opening. Algal density decreases flow rate increases under single sluice regulation conditions. The maximum rate of algal density change reaches 22.13% and 29.55% under double sluice and four sluice scheduling. Algae control effects grow significantly as the number of control sluices increases. The results of this work may provide technical support for water quality forecasting and algae risk warning in the SNWDP MR as well as a workable reference for similar projects.


Assuntos
Rios , Qualidade da Água , China , Ecossistema , Monitoramento Ambiental/métodos , Plantas
11.
Sci Total Environ ; 786: 147480, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33965816

RESUMO

Identifying critical spatial supply chain paths for embodied water flows driven by food demand can guide the development of more spatially explicit food-related policies for water savings. Previous studies have quantified water uses caused by food demand, but overlook intermediate transfer paths within and among regions. That is, spatial supply chain paths describing step-by-step transfer stages between water uses and final food demand have not been well characterized. Based on the multi-regional input-output model and structural path analysis, this study exhaustively identifies critical spatial supply chain paths for provincial water withdrawals driven by final food demand in China. Results show that the final demand of food products from critical sectors (e.g., agricultural products processing, rice, and swine) and regions (e.g., Xinjiang, Heilongjiang, and Guangdong) drives large amounts of water withdrawals. Critical supply chain paths indicate that agricultural products processing, food manufacturing, and catering should pay special attention to increasing the use efficiency of rice, poultry, cotton, water, and gas products, which can effectively reduce national water withdrawals. The interregional paths further provide evidence for interregional cooperation to save food-related water resources, such as the transfer of capital and technologies from agricultural products processing in Shandong to cotton production in Xinjiang and rice production in Heilongjiang. These critical supply chain paths provide spatially explicit and targeted hotspots for demand-side policies. They can also serve for the evaluation of measures in each stage of the supply chain paths.

12.
Sci Bull (Beijing) ; 66(11): 1080-1090, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36654342

RESUMO

Large roughness and structure disorder in ferroelectric ultrathin Langmuir-Blodgett (LB) film results in severe space scatter in electrical, ferroelectric and piezoelectric characteristics, thus limiting the nanoscale research and reliability of nano-devices. However, no effective method aiming at large-area uniform organic ferroelectric LB film has ever been reported to date. Herein, we present a facile hot-pressing strategy to prepare relatively large-area poly(vinylidene fluoride) (PVDF) LB film with ultra-smooth surface root mean square (RMS) roughness is 0.3 nm in a 30 µm × 30 µm area comparable to that of metal substrate, which maximized the potential of LB technique to control thickness distribution. More importantly, compared with traditionally annealed LB film, the hot-pressed LB film manifests significantly improved structure uniformity, less fluctuation in ferroelectric characteristics and higher dielectric and piezoelectric responses, owing to the uniform dipole orientation and higher crystalline quality. Besides, different surface charge relaxation behaviors are investigated and the underlying mechanisms are explained in the light of the interplay of surface charge and polarization charge in the case of nanoscale non-uniform switching. We believe that our work not only presents a novel strategy to endow PVDF LB film with unprecedented reliability and improved performance as a competitive candidate for future ferroelectric tunnel junctions (FTJs) and nano electro mechanical systems (NEMS), but also reveals an attracting coupling effect between the surface potential distribution and nanoscale non-uniform switching behavior, which is crucial for the understanding of local transport characterization modulated by band structure, bit signal stability for data-storage application and the related surface charge research, such as charge gradient microscopy (CGM) based on the collection of surface charge on the biased ferroelectric domains.

13.
Environ Sci Technol ; 54(16): 9791-9803, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32677825

RESUMO

Food, energy, and water resources, which are interconnected with one another, are essential to human beings and sustainable development goals. Existing studies have quantified direct interconnections of food, energy, and water (FEW) systems in China but overlooked their indirect and spatial interconnections through production systems of other products. Quantifying both the direct and indirect spatial interconnections of food, energy, and water systems is the basis of holistic FEW resource management. The spatial interconnections of the FEW systems within China's economic supply chains at the provincial level were quantified from both demand-driven and supply-push perspectives in this study. Results show that food and energy subsystems have tighter coupling relations than the other relationships in the FEW nexus from the demand perspective, and food and water subsystems have tighter coupling relations from the supply perspective. Findings of this study highlight the necessity of demand-side and supply-side measures by identifying critical final consumers and primary suppliers. For example, primary inputs of energy extraction sectors in Inner Mongolia, Shanxi, and Heilongjiang are crucial for national water withdrawals. Sustainable management of FEW resources in China can be better achieved through strengthening the interdepartmental and interregional cooperation from both the demand and supply sides.


Assuntos
Abastecimento de Água , Água , China , Abastecimento de Alimentos , Humanos , Recursos Hídricos
14.
Oxid Med Cell Longev ; 2020: 6181630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32148653

RESUMO

Sleep deprivation adversely affects the digestive system. Multiple studies have suggested sleep deprivation and oxidative stress are closely related. Autophagy can be triggered by oxidative stress as a self-defense strategy to promote survival. In this study, we investigated the effects of sleep deprivation on liver functions, oxidative stress, and concomitant hepatocyte autophagy, as well as the associated pathways. Enzymatic and nonenzymatic biochemical markers in the serum were used to assess hepatic function and damage. To evaluate the occurrence of autophagy, expression of autophagy-related proteins was tested and autophagosomes were labeled. Additionally, methane dicarboxylic aldehyde (MDA), antioxidant enzymes, and the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway were analyzed using chemical methods and a Western blot. Serum alanine transaminase, aspartate aminotransferase, and alkaline phosphatase increased in sleep-deprived rats. Total protein and albumin abundance was also abnormal. Sleep deprivation induced histopathological changes in the liver. The superoxide dismutase level decreased significantly in the liver of sleep-deprived rats. In contrast, the MDA content increased in the sleep deprivation group. Moreover, the microtubule-associated protein 1 light chain 3 beta (LC3B) II/I ratio and Beclin I content increased considerably in the sleep-deprived rats, while p62 levels decreased. Sleep deprivation apparently inhibited the AKT/mTOR signaling pathway. We conclude that sleep deprivation can induce oxidative stress and ultimately cause liver injury. Autophagy triggered by oxidative stress appears to be mediated by the AKT/mTOR pathway and plays a role in relieving oxidative stress caused by sleep deprivation.


Assuntos
Fígado/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Privação do Sono/complicações , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia , Masculino , Ratos , Ratos Wistar , Transdução de Sinais
15.
Materials (Basel) ; 13(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041205

RESUMO

To study the seismic performance of embedded polyvinyl chloride (PVC) pipe confined reinforced high-strength concrete (PVC-RHC) columns, five specimens are designed for cyclic loading test, which include three PVC-RHC column specimens, an embedded circle steel tube confined reinforced high-strength concrete (CST-RHC) column specimen, and a reinforced high-strength concrete (RHC) column specimen. The failure mechanism and morphology are revealed by experiments. The influences of PVC pipe diameter, axial compression ratio, and concrete strength on seismic performance indexes are analyzed. The research results indicate thhe following: all specimens displayed shear baroclinic failure. Compared with RHC specimens, the hysteretic curves of the PVC-RHC specimen and CST-RHC specimen were fuller; furthermore, their energy dissipation capacity, deformation, and ductility were more beneficial. With the increase of the diameter-length ratio and axial pressure, the energy dissipation capacity and deformation capacity of PVC-RHC specimens decreased. The shear bearing capacity of the PVC-RHC specimen calculated with "concrete structure design code" (GB 50010-2010) was smaller than the test results by 25%, showing an excessive safety margin. Thus, according to the failure mechanism of the PVC-RHC specimen, a new calculation formula of shear bearing capacity is deduced, which is in good agreement with the experimental results.

16.
Nanoscale ; 11(43): 20514-20521, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660549

RESUMO

Ferroelectric topological configurations confined in nanostructures have attracted intensive interest both in fundamental physics and potential applications in non-volatile nanoelectronic devices. However, the preparation approaches such as chemical synthesis and template or electron beam etching inevitably induce damage and contamination; also, these are complicated processes. Herein, by a delicate design of the wetting layer and growth temperature, self-assembled ferroelectric nanoislands were achieved with the BiFeO3/(La,Sr)MnO3/LaAlO3 heterostructure. Based on the thermodynamic analysis, the much lower surface energy (∼0.47 J m-2) of the (La,Sr)MnO3 (∼2-12 nm)/LaAlO3 system than that (∼1.0 J m-2) of BiFeO3 provides the probability for the transformation of layered morphology into nanoislands. From the dynamic perspective, the high growth temperature (∼650-680 °C) helps to step over the energy barrier (∼50 meV per atom) by stimulating the formation of periodically arrayed dislocations at the BiFeO3/(La,Sr)MnO3 interface, which on the one hand releases the epitaxial elastic energy and on the other hand evokes the nucleation of the R-phase nanoisland array. More excitingly, this approach with a wonderful new growth mechanism can also be employed in other ferroelectric model systems such as BaTiO3, which provides a new strategy for the design of novel nanoelectronic devices based on ferroelectric perovskite nanostructures.

17.
Environ Sci Technol ; 53(3): 1432-1440, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30602110

RESUMO

While direct greenhouse gas (GHG) emissions by China's power sector from the generation side have been widely investigated, driving forces from the electricity consumption perspective and inter-regional electricity transmission have been overlooked to a large extent. This study quantified relative contributions of six factors to changes in GHG emissions from interconnected grids in China during 2008-2015. These six factors include three generation-side factors (i.e., fuel mix of thermal power generation, energy efficiency of thermal power generation, and electricity structure), two consumption-side factors (i.e., electricity efficiency of GDP and GDP), and electricity transmission structure. GDP growth and changes in fuel mix of thermal power generation are two major drivers of increased GHG emission during 2008-2015, especially for the North China Grid. In contrast, changes in electricity transmission structure (especially in East China Grid and Southern China Grid), the increase in electricity efficiency of GDP (except for Northwest China Grid), improvements in energy efficiency of thermal power generation (especially in North China Grid and Central China Grid), and changes in electricity structure (especially in Southern Power Grid) are major factors offsetting GHG emission increments. Findings of this study can provide multiple-perspective policy implications for GHG mitigation in China's power sector.


Assuntos
Gases de Efeito Estufa , China , Eletricidade , Efeito Estufa
18.
Zhonghua Nan Ke Xue ; 23(8): 687-691, 2017 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29726641

RESUMO

OBJECTIVE: To investigate the influence of deep slow-wave sleep deprivation on the oxidative stress of testicular tissue in rats. METHODS: Thirty-six 5-week-old male Wistar rats were equally randomized into deep slow-wave sleep deprivation group (SD1), deep slow-wave sleep and duration sleep deprivation group ( SD2), and a cage control group (CC). The rat model of deep slow-wave sleep deprivation was established using the flowerpot technique. The rats in the SD1 group were interfered every 24 minutes and deprived of 12 hours of sleep at night, those in the SD2 group deprived of 8 minutes of sleep at an interval of 24 minutes and 12 hours of sleep at night, and those in the CC group exposed to 12 hours of daylight and 12 hours of darkness. After 28 days, all the rats were executed for measurement of the testis volume and protein content, determination of the methane dicarboxylic aldehyde (MDA) level and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and observation of the pathological changes in the testicular tissue under the microscope. RESULTS: Compared with the CC group, the rats in the SD1 and SD2 groups showed significantly reduced body weight (ï¼»268.5 ± 1.6ï¼½ vs ï¼»248.1 ± 25.1ï¼½andï¼»232.9 ± 10.1ï¼½g, P<0.05) and increased relative testis mass (ï¼»50.0 ± 1.3ï¼½ vs ï¼»57.9 ± 6.1ï¼½ and ï¼»54.9 ± 3.5ï¼½ ×10⁻², P<0.05). Statistically significant differences were found between the CC and SD2 groups in the contents of protein (ï¼»6.3 ± 1.4ï¼½ vs ï¼»4.5 ± 0.9ï¼½ gpro/L, P<0.05) and MDA (ï¼»1.1 ± 0.1ï¼½ vs ï¼»1.3 ± 0.3ï¼½ nmol/mgpro, P<0.05) and the activities of SOD (ï¼»104.3 ± 33.1ï¼½ vs ï¼»135.2 ± 26.9ï¼½ U/mgpro, P<0.05) and GSH-Px (ï¼»15.6 ± 4.0ï¼½ vs ï¼»21.7 ± 4.3ï¼½ U/mgpro, P<0.05), but not between the CC and SD1 groups (P>0.05). The lumens in the testis were narrowed, with obvious hyperplasia, hyperemia and edema in the peripheral interstitial tissue, but no significant pathologic changes were observed in the testis tissue of the SD1 group. CONCLUSIONS: Long-term deprivation of deep slow-wave sleep impairs the structure of the testis tissue and induces oxidative stress response in rats.


Assuntos
Estresse Oxidativo , Privação do Sono/metabolismo , Testículo/metabolismo , Testículo/patologia , Animais , Peso Corporal , Glutationa Peroxidase/análise , Masculino , Malondialdeído , Distribuição Aleatória , Ratos , Ratos Wistar , Fases do Sono , Superóxido Dismutase/análise , Fatores de Tempo , Redução de Peso
19.
J Agric Food Chem ; 61(11): 2796-802, 2013 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-23458314

RESUMO

The Monascus species has been used in foods for thousands of years in China. In this study, 10 azaphilone pigments, including four yellow and six orange pigments, were isolated from the fermented rice and dioscorea of Monascus purpureus NTU 568. By employing lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells, we determined the inhibitory activities of these pigments on nitric oxide (NO) production. As a result, four orange pigments, monaphilols A-D, showed the highest activities (IC50 = 1.0-3.8 µM), compared with the other two orange pigments, monascorubrin (IC50 > 40 µM) and rubropunctatin (IC50 = 21.2 µM), and the four yellow pigments ankaflavin (IC50 = 21.8 µM), monascin (IC50 = 29.1 µM), monaphilone A (IC50 = 19.3 µM), and monaphilone B (IC50 = 22.6 µM). Using Western blot and ELISA kits, we found that treatments with 30 µM of the yellow pigments and 5 µM of the orange pigments could down-regulate the protein expression of inducible nitric oxide synthase (iNOS) and suppress the production of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6). We also used two animal experiments to evaluate the anti-inflammatory effects of these pigments. In a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema model, eight of these pigments (0.5 mg/ear) could prevent ear edema against TPA administrations on the ears of BALB/c mice. In an LPS-injection mice model, several of these pigments (10 mg/kg) could inhibit the NO, TNF-α, IL-1ß, and IL-6 levels in the plasma of BALB/c mice. As concluded from the in vitro and in vivo studies, six azaphilonoid pigments, namely, ankaflavin, monaphilone A, and monaphilols A-D, showed high potential to be developed into chemopreventive foods or drugs against inflammation-associated diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Edema/tratamento farmacológico , Monascus/química , Pigmentos Biológicos/administração & dosagem , Animais , Anti-Inflamatórios/metabolismo , Cor , Edema/genética , Edema/imunologia , Humanos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monascus/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Pigmentos Biológicos/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
20.
J Tradit Complement Med ; 3(1): 33-40, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24716153

RESUMO

Seventeen compounds, quercetin-3-O-α-l-rhamnoside (1), kaempferol-3-O-α-L-rhamnoside (2), apigenin-7-O-ß-D-glucuronide (3), apigenin 7-O-ß-D-glucuronide methyl ester (4), apigenin 7-O-ß-D-glucuronide ethyl ester (5), chrysoeriol (6), apigenin (7), kaempferol (8), luteolin (9), quercetin (10), methyl 3,4-dihydroxybenzoate (11), p-coumaric acid (12), 4-hydroxybenzoic acid (13), hydroquinone (14), protocathehuic acid (15), gallic acid (16), and indole-3-carboxylic acid (17), were isolated from the ethanol extract of Taiwanese Cardiospermum halicabum. All chemical structures were determined by physical and extensive spectroscopic analyses such as (1) H Nuclear Magnetic Resonance spectroscopy (NMR), (13)C NMR, (1)H-(1)H Correlation spectroscopy ((1)H-(1)H COSY), Heteronuclear Multiple Quantum Coherence spectroscopy (HMQC), Heteronuclear Multiple-bond Correlation spectroscopy (HMBC), and Nuclear Overhauser Effect spectroscopy (NOESY), as well as comparison with literature values. Furthermore, the High-Performance Liquid Chromatography- Photodiode Array Detector (HPLC-DAD) fingerprint profile was established for the determination of major constituents in the EtOAc extract and retention times of the isolated compounds. All isolated compounds were also evaluated for antiinflammatory and antioxidant activities.

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