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1.
J Environ Manage ; 356: 120484, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522276

RESUMO

The large-scale application of hydrogen steelmaking technology is expected to substantially accelerate the decarbonization process of the iron and steel industry. However, hydrogen steelmaking projects are still in the experimental or demonstration stage, and scientific investment decision-making methods are urgently needed to support the large-scale development of the technology. When assessing the investment value, existing studies usually only consider the intrinsic project value under a specific pathway, while ignoring the option value under realistic multiple uncertainties in terms of technology, market, and policy, leading to an underestimation of the investment value. To address this issue, this study constructs a real options model to explore the optimal investment timing and revenue of the hydrogen steelmaking project, by taking into account multi-dimensional uncertainties stemming from price fluctuations in the steel market, the development of the carbon market, and technological advances. Additionally, the impacts of various subsidy policies on the investment strategy are also investigated. Least Squares Monte Carlo method is applied to overcome computational challenges posed by dynamic programming under multi-dimensional uncertainties. The results show that: (i) Investment is not recommended based on current crude steel price and hydrogen price. (ii) When the annual reduction rate of hydrogen price reaches 5%, the optimal investment timing would advance to 2036. (iii) On this basis, with the introduction of a 20% green hydrogen subsidy policy, the optimal investment timing would be further brought forward to 2033. The implementation of tax incentives would significantly increase the investment value. The investment value would surge from 170 million CNY to 262 million CNY as the tax rate decreases from 20% to zero. The findings could provide reasonable suggestions for investment decisions under realistic volatile environments, as well as scientific references for policy design, thus facilitating the large-scale and high-level development of hydrogen-based steelmaking technology.


Assuntos
Investimentos em Saúde , Ferro , Incerteza , Aço , Indústrias
2.
J Am Chem Soc ; 145(3): 1542-1547, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36622693

RESUMO

Regioselective difunctionalization of arenes remains a long-standing challenge in organic chemistry. We report a novel and general Fe/Ti synergistic methodology for regioselective synthesis of various polysubstituted arenes through either E/E' or Nu/E ortho difunctionalizations of arenes. Preliminary results showed that an unprecedented 1,2-Fe/Ti heterobimetallic arylene intermediate bearing two distinct C-M bonds is essential to the regioselective difunctionalization.

3.
Environ Sci Technol ; 57(20): 7709-7720, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37154621

RESUMO

To achieve carbon neutrality (i.e., net zero carbon emissions) by 2060, China must make significant changes in its socioeconomic systems, including appropriately allocating emissions responsibility. Traditional methods of delineating responsibilities (such as production-based and consumption-based accounting) can lead to double counting when applied simultaneously and therefore difficulty in determining responsibilities of different agents. An alternative approach based on economic welfare gains from environmental externalities has been refined, ensuring that the responsibilities of consumers and producers add up to the total emissions. The application of this approach to 48 countries and 31 Chinese provinces reveals that regions with less elastic supply and demand, such as Hebei in China and Russia, have higher responsibilities. Furthermore, larger externalities associated with unitary product value shift the burden of obligations from producers to consumers. Regions with high levels of wealth and carbon-intensive imports, such as Zhejiang and Guangdong in China, as well as the United States, typically have higher consumer-based accounting (CBA) emissions than production-based accounting (PBA) emissions and, as a result, redistributed responsibilities between PBA and CBA emissions. The new distribution results vary significantly from PBA or CBA emissions, indicating opportunities for more comprehensive and accessible policy goals.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/análise , China , Federação Russa , Desenvolvimento Econômico
4.
Health Econ ; 32(4): 953-969, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36639879

RESUMO

Extreme temperatures are known to cause adverse health outcomes. Yet knowledge on the magnitude of this effect in developing countries is limited due to data availability and reliability issues. Collecting data for 2872 counties in China, we estimate the effects of daily temperatures on the monthly mortality rate. The results indicate that an additional day for which the maximum temperature is 38°C or above on average increases the monthly mortality rate by about 1.7% relative to if that day's maximum temperature had been in the range 16-21°C. This is after deducting deaths harvested from the subsequent month. Higher gross domestic product per capita at the county level is associated with lower mortality effects of hot and cold days. Improved dwelling conditions are found to be associated with a lower mortality effect of hot days and improved local healthcare infrastructure to be associated with a lower mortality effect of cold days. In the absence of strong adaptation efforts, the estimates suggest net upward pressure on annual mortality rates over coming decades in many populous counties, especially under more extreme climate change scenarios.


Assuntos
Temperatura Baixa , Temperatura Alta , Humanos , Temperatura , Reprodutibilidade dos Testes , China/epidemiologia , Mortalidade
5.
J Clin Periodontol ; 50(9): 1253-1263, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37381658

RESUMO

AIM: Porphyromonas gingivalis (P. gingivalis), a major periodontal pathogen, increases the risk of systemic diseases. P. gingivalis infection is closely associated with alcoholic liver disease (ALD), but the underlying mechanism remains unclear. We aimed to investigate the role of P. gingivalis in the pathogenesis of ALD. MATERIALS AND METHODS: An ALD mouse model was established using a Lieber-DeCarli liquid diet, and C57BL/6 mice were treated with P. gingivalis to detect the pathological indicators of ALD. RESULTS: Oral administration of P. gingivalis exacerbated alcohol-induced alterations in the gut microbiota, leading to gut barrier dysfunction and inflammatory response and disruption of the T-helper 17 cell/T-regulatory cell ratio in the colon of ALD mice. Furthermore, P. gingivalis worsened liver inflammation in ALD mice by increasing the protein expression of toll-like receptor 4 (TLR4) and p65, increasing the mRNA expression of interleukins-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) and up-regulating the transforming growth factor-beta 1 (TGF-ß1) and galectin-3 (Gal-3) production. CONCLUSIONS: These results indicate that P. gingivalis accelerates the pathogenesis of ALD via the oral-gut-liver axis, necessitating a new treatment strategy for patients with ALD complicated by periodontitis.


Assuntos
Microbioma Gastrointestinal , Hepatopatias Alcoólicas , Animais , Camundongos , Porphyromonas gingivalis , Microbioma Gastrointestinal/genética , Camundongos Endogâmicos C57BL , Imunidade
6.
Depress Anxiety ; 39(12): 845-857, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36329675

RESUMO

BACKGROUND: In the last decade, suicidality has been increasingly theorized as a distinct phenomenon from major depressive disorder (MDD), with unique psychological and neural mechanisms, rather than being mostly a severe symptom of MDD. Although decision-making biases have been widely reported in suicide attempters with MDD, little is known regarding what components of these biases can be distinguished from depressiveness itself. METHODS: Ninety-three patients with current MDD (40 with suicide attempts [SA group] and 53 without suicide attempts [NS group]) and 65 healthy controls (HCs) completed psychometric assessments and the balloon analog risk task (BART). To analyze and compare decision-making components among the three groups, we applied a five-parameter Bayesian computational modeling. RESULTS: Psychological assessments showed that the SA group had greater suicidal ideation and psychological pain avoidance than the NS group. Computational modeling showed that both MDD groups had higher risk preference and lower ability to learn and adapt from within-task observations than HCs, without differences between the SA and NS patient groups. The SA group also had higher loss aversion than the NS and HC groups, which had similar loss aversion. CONCLUSIONS: Our BART and computational modeling findings suggest that psychological pain avoidance and loss aversion may be important suicide risk factor that are distinguishable from depression illness itself.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/psicologia , Tentativa de Suicídio/psicologia , Teorema de Bayes , Ideação Suicida , Viés , Simulação por Computador , Dor
7.
Chin J Cancer Res ; 34(2): 83-94, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35685993

RESUMO

Objective: T-cell lymphoblastic lymphoma (T-LBL) is an aggressive neoplasm of precursor T cells, however, detailed genome-wide sequencing of large T-LBL cohorts has not been performed due to its rarity. The purpose of this study was to identify putative driver genes in T-LBL. Methods: To gain insight into the genetic mechanisms of T-LBL development, we performed whole-exome sequencing on 41 paired tumor-normal DNA samples from patients with T-LBL. Results: We identified 32 putative driver genes using whole-exome sequencing in 41 T-LBL cases, many of which have not previously been described in T-LBL, such as Janus kinase 3 (JAK3), Janus kinase 1 (JAK1), Runt-related transcription factor 1 (RUNX1) and Wilms' tumor suppressor gene 1 (WT1). When comparing the genetic alterations of T-LBL to T-cell acute lymphoblastic leukemia (T-ALL), we found that JAK-STAT and RAS pathway mutations were predominantly observed in T-LBL (58.5% and 34.1%, respectively), whereas Notch and cell cycle signaling pathways mutations were more prevalent in T-ALL. Notably, besides notch receptor 1 (NOTCH1), mutational status of plant homeodomain (PHD)-like finger protein 6 (PHF6) was identified as another independent factor for good prognosis. Of utmost interest is that co-existence of PHF6 and NOTCH1 mutation status might provide an alternative for early therapeutic stratification in T-LBL. Conclusions: Together, our findings will not only provide new insights into the molecular and genetic mechanisms of T-LBL, but also have tangible implications for clinical practice.

8.
Mol Phylogenet Evol ; 154: 106995, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33164871

RESUMO

Phylogenetic assessments of functional traits are important for mechanistically understanding the interactions between organisms and environments, but such practices are strongly limited by the availability of phylogenetic frameworks. The tomocerin springtails are an ancient, widespread and ecologically important group of terrestrial arthropods, whereas their phylogeny and trait evolution remained unaddressed. In the present study, we conducted the first comprehensive phylogenetic reconstruction of Tomocerinae, based on a multi-loci molecular dataset covering all major lineages within the subfamily, using Bayesian inference (BI), maximum-likelihood (ML) and maximum-parsimony (MP) approaches. Divergence time was estimated and ancestral character state reconstruction (ACSR) was performed to trace the evolutionary history of five ecomorphological traits correlated with sensory and locomotory functions. Our results support the monophyly of Tomocerinae, and indicate that current classification of Tomocerinae only partially reflects evolutionary relationships, notably the commonest and speciose genus Tomocerus is polyphyletic. The subfamily probably originated in Early Cretaceous and diversified in two Cretaceous and one Eocene radiation events. As indicated by the evolutionary patterns of functional traits, multiple ecological divergences took place during the diversification of Tomocerinae. The study suggests a potential underestimation of ecological divergence and functional diversity in terrestrial arthropods, calls for an update of present trait databases, and demonstrates the value of macroevolutionary knowledge for improving the trait-based ecology. In addition, Tomocerus, Tomocerina and Tritomurus are redefined, a new genus Yoshiicerusgen. n. and new subgenera Coloratomurussubgen. n., Ciliatomurussubgen. n., Striatomurussubgen. n. and Ocreatomurussubgen. n. are described in the appendix.


Assuntos
Artrópodes/classificação , Artrópodes/genética , Biodiversidade , Filogenia , Característica Quantitativa Herdável , Animais , Teorema de Bayes , Funções Verossimilhança , Fenótipo , Fatores de Tempo
9.
Fish Shellfish Immunol ; 102: 368-380, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32360914

RESUMO

Anti-lipopolysaccharide factor (ALF), which belongs to the antimicrobial peptide (AMP) family, has become a relatively new weapon to combat severe infections and has been demonstrated to be active against bacteria, fungi and some viruses. In the present study, a new ALF of group D (MjALF-D; GenBank accession No. MN416688) from Marsupenaeus japonicus was detected. MjALF-D encodes a polypeptide with 124 aa, and the peptide contains a 26-residue signal peptide and a lipopolysaccharide-binding domain (LBD). The structure of MjALF-D was found to consist of three α-helices, four ß-sheets and random coils. qRT-PCR analysis revealed that MjALF-D expression was primarily observed in the stomach and was universally upregulated in both the gill and stomach after challenge by lipopolysaccharide (LPS) and Vibrio parahaemolyticus. Moreover, rMjALF-D can inhibit the growth of V. parahaemolyticus. rMjALF-D could destroy the bacterial membrane and lead to cytoplasmic leakage investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which may be the mechanism by which rMjALF-D inhibits V. parahaemolyticus. Additionally, rMjALF-D showed distinct binding or antibacterial ability after direct incubation with V. parahaemolyticus or bacterial genomic DNA and a certain effect on the protein expression of it. Together, these results indicated that rMjALF-D possessed the antibacterial activity against V. parahaemolyticus and the potential involvement in the innate immune response of M. japonicus.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/imunologia , Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Regulação para Cima/imunologia , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/química , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Lipopolissacarídeos/farmacologia , Filogenia , Distribuição Aleatória , Alinhamento de Sequência , Vibrio parahaemolyticus/fisiologia
10.
J Environ Manage ; 271: 110975, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32579527

RESUMO

China has launched pilot carbon emissions permit trading schemes (ETS) in seven regions since 2013/2014 and has established a nationwide ETS in the power industry by the end of 2017. Recent literature has evaluated China's seven pilot regions on design aspects of the ETS, and yet little is known about the potential recovery of economic output loss through introducing the ETS. This study considers the recovery of industrial value added loss and thus measures the abatement cost savings from trading to evaluate the necessity and feasibility of China's pilot ETSs. The analysis develops a parametric and nonparametric combined technique to calculate the opportunity abatement cost savings (i.e., potential abatement cost savings and unrealized abatement cost savings) and marginal abatement cost savings (i.e., changes on carbon shadow prices) in China's pilot ETSs during 2011-2015. It additionally provides an estimation of potential carbon emissions reduction from ETS. Both cross-industrial trading and intertemporal trading are considered, and three simulations, defined as no trading, cross-industrial trading, and cross-industrial and intertemporal trading, are conducted. We found that, i) 1-16% potential abatement cost savings and 2-12% unrealized abatement cost savings would be identified in China's pilot ETS regions. ii) 0.5-33% and 1.6-25% carbon emissions reduction potential would be realized respectively by introducing ETS and eliminating the operational inefficiency of the ETS. iii) Marginal abatement cost savings would both exist in almost all regions if the ETS were implemented and if the ETS were fully operational.


Assuntos
Carbono/análise , Gases de Efeito Estufa , China , Redução de Custos , Indústrias
11.
J Org Chem ; 84(9): 5176-5186, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-30912656

RESUMO

The combination of commonly used FeCl3/SIPr with Ti(OEt)4/PhOM enabled a highly general iron-based catalyst system, which could efficiently catalyze the biaryl coupling reaction between various electrophiles (I, Br, Cl, OTs, OCONMe2, OSO2NMe2) and common or functionalized aryl Grignard reagents with high functional group tolerance. Selective couplings of aryl iodides and bromides over the corresponding oxygen-based electrophiles have been achieved, and thus a terphenyl acid intermediate for anidulafungin was conveniently synthesized via an orthogonal coupling strategy.

12.
Sensors (Basel) ; 20(1)2019 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-31905779

RESUMO

In the semi-aviation frequency-domain electromagnetic measurement, the induction air-core coil and the differential pre-amplifier circuit introduce noise, which affects the sensor and results in receiving weak signals and improving the signal-to-noise ratio of the system. In response to this problem, by analyzing the physical structure of the air-core coil sensor and the mechanism of the amplification circuit, combined with the simulation and experimental tests of voltage noise, current noise, resistance noise and other noise components, analyzed that the thermal noise is the main component of the sensor noise in the system frequency band, but directly removing the matching resistor increases the instability of the circuit, causes the coil to work in an underdamped state, and generates a time domain oscillation at the resonant frequency, source impedance analysis and analysis of differential pre-amplifier circuit in the frequency-domain detection method, abandoning the matching resistance scheme and magnetic flux negative feedback scheme. The matching capacitor is added to make the receiver detect the frequency range in the 1-10 kHz range. In normal operation, the noise level reaches 10 nV level, which not only increases the stability of the circuit, but also reduces the noise of the sensor. It has far-reaching significance for the detection of weak frequency signals.

14.
Ecotoxicol Environ Saf ; 156: 366-374, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29574319

RESUMO

Intensive shrimp farming is generally accompanied by nutrient enrichment and gradual eutrophication, which impose major threats to shrimp culture ecosystems. However, little is known about how the bacterioplankton community in a rearing environment responds to increased eutrophication during shrimp culture processes. In this study, we used the MiSeq sequencing technique to explore the impacts of nutrient enrichment on the assembly and stability of the bacterioplankton community. Our results showed that magnitudes of the changes in the bacterioplankton community compositions (BCCs) and diversity were closely associated with eutrophication level. Moreover, a phylogenetic-based mean nearest taxon distance (MNTD) analysis revealed that increased eutrophication significantly (P < 0.01) changed the bacterioplankton ecological processes from deterministic to stochastic. A structural equation model showed that eutrophication indicators affected the BCCs either directly by controlling resources or indirectly by modifying other environmental variables of the shrimp ponds in complex pathways. Furthermore, association network comparisons revealed that nutrient enrichment increased the complexity of interspecies interactions and the proportion of cooperative interactions and decreased the proportion of generalists, which suggest that nutrient enrichment destroyed the community stability. These findings suggest that minimizing nutrient pollution, especially at the end of cultivation, could be an important management tool for establishing a microbially mature water system.


Assuntos
Aquicultura , Bactérias/crescimento & desenvolvimento , Crustáceos/microbiologia , Plâncton/crescimento & desenvolvimento , Microbiologia da Água , Amônia/análise , Animais , Análise da Demanda Biológica de Oxigênio , DNA Bacteriano/isolamento & purificação , Ecossistema , Eutrofização , Concentração de Íons de Hidrogênio , Nitratos/análise , Nitritos/análise , Ácidos Fosfóricos/análise , Filogenia , Análise de Sequência de DNA , Água/química
15.
J Environ Manage ; 192: 254-270, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28183026

RESUMO

The trend toward a more fiercely competitive and strictly environmentally regulated electricity market in several countries, including China has led to efforts by both industry and government to develop advanced performance evaluation models that adapt to new evaluation requirements. Traditional operational and environmental efficiency measures do not fully consider the influence of market competition and environmental regulations and, thus, are not sufficient for the thermal power industry to evaluate its operational performance with respect to specific marketing goals (operational effectiveness) and its environmental performance with respect to specific emissions reduction targets (environmental effectiveness). As a complement to an operational efficiency measure, an operational effectiveness measure not only reflects the capacity of an electricity production system to increase its electricity generation through the improvement of operational efficiency, but it also reflects the system's capability to adjust its electricity generation activities to match electricity demand. In addition, as a complement to an environmental efficiency measure, an environmental effectiveness measure not only reflects the capacity of an electricity production system to decrease its pollutant emissions through the improvement of environmental efficiency, but it also reflects the system's capability to adjust its emissions abatement activities to fulfill environmental regulations. Furthermore, an environmental effectiveness measure helps the government regulator to verify the rationality of its emissions reduction targets assigned to the thermal power industry. Several newly developed effectiveness measurements based on data envelopment analysis (DEA) were utilized in this study to evaluate the operational and environmental performance of the thermal power industry in China during 2006-2013. Both efficiency and effectiveness were evaluated from the three perspectives of operational, environmental, and joint adjustments to each electricity production system. The operational and environmental performance changes over time were also captured through an effectiveness measure based on the global Malmquist productivity index. Our empirical results indicated that the performance of China's thermal power industry experienced significant progress during the study period and that policies regarding the development and regulation of the thermal power industry yielded the expected effects. However, the emissions reduction targets assigned to China's thermal power industry are loose and conservative.


Assuntos
Meio Ambiente , Indústrias , China , Eficiência , Regulamentação Governamental , Modelos Teóricos
16.
Environ Monit Assess ; 188(5): 307, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27106208

RESUMO

This paper presents numerical investigations on quantifying the hydrodynamic effects of coastal environment factors, including tidal fluctuations, beach slopes, hydraulic conductivity, and hydraulic gradients on sea-derived benzene transport in unconfined coastal aquifers. A hydrologic transport and mixed geochemical kinetic/equilibrium reactions in saturated-unsaturated media model was used to simulate the spatial and temporal behaviors of the density flow and benzene transport for various hydrogeological conditions. Simulation results indicated that the tidal fluctuations lead to upper saline plumes (USPs) near the groundwater and seawater interfaces. Such local circulation zones trapped the seaward benzene plumes and carried them down in aquifers to the depth depending on the tide amplitudes and beach slopes across the coastal lines. Comparisons based on different tidal fluctuations, beach slopes, hydraulic conductivity, and hydraulic gradient were systematically conducted and quantified. The results indicated that areas with USPs increased with the tidal amplitude and decreased with the increasing beach slope. However, the variation of hydraulic conductivity and hydraulic gradient has relatively small influence on the patterns of flow fields in the study. The increase of the USP depths was linearly correlated with the increase of the tidal amplitudes. The benzene reactive transport simulations revealed that the plume migrations are mainly controlled by the local flow dynamics and constrained in the USP circulation zones. The self-cleaning process of a coastal aquifer is time-consuming, typically requiring double the time of the contamination process that the benzene plume reach the bottom of a USP circulation zone. The presented systematic analysis can provide useful information for rapidly evaluating seaward contaminants along a coastal line with available hydrogeological properties.


Assuntos
Benzeno/análise , Monitoramento Ambiental , Água Subterrânea/química , Movimentos da Água , Poluentes Químicos da Água/análise , Hidrodinâmica , Hidrologia , Modelos Químicos , Água do Mar/química
17.
Mitig Adapt Strateg Glob Chang ; 20(8): 1335-1359, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30197558

RESUMO

This paper presents a modeling comparison on how stabilization of global climate change at about 2 °C above the pre-industrial level could affect economic and energy systems development in China and India. Seven General Equilibrium (CGE) and energy system models on either the global or national scale are soft-linked and harmonized with respect to population and economic assumptions. We simulate a climate regime, based on long-term convergence of per capita carbon dioxide (CO2) emissions, starting from the emission pledges presented in the Copenhagen Accord to the United Nations Framework Convention on Climate Change and allowing full emissions trading between countries. Under the climate regime, Indian emission allowances are allowed to grow more than the Chinese allowances, due to the per capita convergence rule and the higher population growth in India. Economic and energy implications not only differ among the two countries, but also across model types. Decreased energy intensity is the most important abatement approach in the CGE models, while decreased carbon intensity is most important in the energy system models. The reduction in carbon intensity is mostly achieved through deployment of carbon capture and storage, renewable energy sources and nuclear energy. The economic impacts are generally higher in China than in India, due to higher 2010-2050 cumulative abatement in China and the fact that India can offset more of its abatement cost though international emission trading.

18.
Addict Biol ; 19(6): 996-1005, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23750993

RESUMO

Cocaine sensitization and reward are reported to be under the influence of diurnal rhythm. However, no previous studies have reported brain areas that play a role as modulators and underlie the mechanism of diurnal variations in cocaine reward. We examined (1) the diurnal rhythm of glycogen synthase kinase-3ß (GSK-3ß) activity in the suprachiasmatic nucleus (SCN) and reward-related brain areas in naive rats; (2) the effect of day and night on the acquisition of cocaine-induced conditioned place preference (CPP); (3) the influence of cocaine-induced CPP on GSK-3ß activity in the SCN and reward-related brain areas; and (4) the effect of the GSK-3ß inhibitor SB216763 microinjected bilaterally into the ventral tegmental area (VTA) on cocaine-induced CPP. A significant diurnal rhythm of GSK-3ß activity was found in the SCN and reward-related brain areas, with diurnal variations in cocaine-induced CPP. GSK-3ß activity in the SCN and reward-related brain areas exhibited marked diurnal variations in rats treated with saline. GSK-3ß activity in rats treated with cocaine exhibited distinct diurnal variations only in the prefrontal cortex and VTA. Cocaine decreased the expression of phosphorylated GSK-3ß (i.e. increased GSK-3ß activity) only in the VTA in rats trained and tested at ZT4 and ZT16. SB216763 microinjected into the VTA bilaterally eliminated the diurnal variations in cocaine-induced CPP, but did not affect the acquisition of cocaine-induced CPP. These findings suggest that the VTA may be a critical area involved in the diurnal variations in cocaine-induced CPP, and GSK-3ß may be a regulator of diurnal variations in cocaine-induced CPP.


Assuntos
Cocaína/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Inibidores da Captação de Dopamina/farmacologia , Quinase 3 da Glicogênio Sintase/fisiologia , Área Tegmentar Ventral/enzimologia , Animais , Ritmo Circadiano/efeitos dos fármacos , Indóis/farmacologia , Masculino , Maleimidas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Ratos Sprague-Dawley , Recompensa , Núcleo Supraquiasmático/enzimologia , Área Tegmentar Ventral/efeitos dos fármacos
19.
Sci Total Environ ; 912: 168634, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37981165

RESUMO

China proposed a target to achieve carbon neutrality before 2060. Wind power is crucial for mitigating climate change and achieving carbon neutrality. However, its development depends on the potential constraints of rare-earth elements. Therefore, first projecting the rare-earth demand for wind power equipment in the context of achieving carbon neutrality and identifying potential obstacles are necessary. However, the carbon-neutral pathway for China's power sector is unclear, let alone the corresponding rare-earth demand. Consequently, this study explores a potential cost-effective carbon-neutral pathway for China's power sector and quantifies the demand for rare-earth elements used for producing wind power equipment under different pathways, by integrating dynamic material flow analysis and a national energy technology model. The results showed that the rare-earth supply may be inadequate for wind power development in terms of achieving carbon neutrality in China, especially for dysprosium and terbium. To neutralise the carbon emissions of China's power sector, the cumulative rare-earth demand during 2021-2060 would be 222-434 kt, of which at most 1/3 could potentially be obtained by circular usage from end-of-life wind turbines. However, the existing low secondary recovery rate of rare-earth elements makes the available circular amounts very small. Shifting to a wind power market dominated by direct-drive turbines may increase the cumulative rare-earth demand by up to 34 %. Without material intensity reduction for the wind power technologies, an additional 38 % demand for rare-earth elements will occur, exacerbating the risk of shortage.

20.
Polymers (Basel) ; 16(12)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38932039

RESUMO

Metallocene catalysts have attracted much attention from academia and industry for their excellent catalytic activity in the field of olefin polymerization. Cocatalysts play a key role in metallocene catalytic systems, which can not only affect the overall catalytic activity, but also have an obvious influence on the structure and properties of the polymer. Although methylaluminoxane (MAO) is currently the most widely used cocatalyst, its price increases the production cost of polyolefin materials. Ammonium tetrakis(pentafluorophenyl)borate has shown excellent performance in polymerization, being one of the best substitutes for the traditional cocatalyst MAO. Compared with the main catalyst, whose composition and structure are relatively complex, the research on cocatalyst is very limited. This review mainly introduces the research history, preparation methods, and application progress in polymerization of ammonium tetrakis(pentafluorophenyl)borate, deepening our understanding of the role of cocatalyst in polymerization, with the hope of inspiring brand-new thinking on improving and enhancing the overall performance of catalyst systems.

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