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1.
Int J Biol Macromol ; : 132993, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38862049

RESUMO

Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.

2.
ACS Appl Mater Interfaces ; 15(48): 56242-56252, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37976415

RESUMO

A porous hydrogen-bonded organic framework (HOF) structure was explored for the first time in the design of high-performance electrochromic devices (ECDs) using polyoxometalate (POM)-based charge-balancing layers as counter electrodes (CEs). The novelty of this work lies in the facile construction of films using small molecule-based EC materials to form a porous HOF structure. A full-cell model of an ECD was constructed by utilizing a POM-based CE to optimize the voltage distribution on the HOF-coated working electrode (WE). The addition of PW12O403- (PW12) on CE significantly enhanced the voltage distribution on EC electrodes and decreased the overvoltage on the WE, further preventing the formation of non-EC species and resulting in a 3.3-fold increase in the lifetime of the ECD. The optical contrast was enhanced from 47% (TiO2 only) to 68%, and the coloration efficiency was enhanced from 185 (TiO2 only) to 373 cm2 C-1. The optimized voltage distribution on the WE, leading to the fast response time and high optical EC contrast, could be explained by the charge-balancing effect. Overall, this new finding provides a robust framework for designing high-performance ECDs, taking advantage of the porous morphology and potential matching of the HOF and PW12.

3.
Environ Sci Pollut Res Int ; 30(40): 93227-93241, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37507562

RESUMO

This paper discusses the dynamic long- and short-term effects of bitcoin price (BTP), crude oil price (COP), and uncertainty of economic policy (EPU) on China's green bond (CGB) market, separately. Depending on the quantile autoregressive distributed lag method, the empirical results are shown that BTP and EPU exert substantial positive and negative effects on the CGB market in the long term for most circumstances, while their effects reflect not prominent in the short term. The main contributions can be summarized as follows. Given that China is the largest bitcoin mining state and a major green bond issuer, this study first explores the linkages between them. Furthermore, both long- and short-term effects are investigated from BTP, COP, and EPU to CGB, and long-term effects are dominated in the interrelationships among variables, indicating that the CGB market is mainly driven by permanent shocks. In addition, the mentioned long-term effects are deeply discussed from time- and quantile-varying aspects. This approach considers diverse situations in the bond market and various incidents that occur at various durations of time. The results underscore the significance of market participants gaining a deeper comprehension of how BTP, COP, and EPU impact green bond within varying market conditions. Implementing specific policies, such as establishing a cohesive and efficient bond market and making careful adjustments to economic policies, can be advantageous in maintaining stability within the CGB market.


Assuntos
Petróleo , Humanos , Incerteza , China , Políticas , Desenvolvimento Econômico
4.
Pest Manag Sci ; 78(5): 2011-2021, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35118797

RESUMO

BACKGROUND: Insect pests seriously decrease the yield and quality of agricultural crops. Resistance to commonly used insecticides is increasingly undermining their effectiveness, and therefore the development of agents with novel modes of action is desirable. Isoxazolines are a new class of insecticides that act on γ-aminobutyric acid (GABA) gated chloride channels. In this work, we used the highly active 4-triazolyphenyl isoxazoline DP-9 as a parent structure to design and synthesize a series of quaternary ammonium salt (QAS) derivatives, and we systematically evaluated their insecticidal and antifungal activities. RESULTS: Many of the synthesized QASs exhibit insecticidal activities equivalent to or higher than that of DP-9. In particular, compounds I-31 (93%, 0.00005 mg/L) and I-34 (80%, 0.00001 mg/L) showed insecticidal activities against diamondback moth larvae that were 2-10 times higher than those of fluralaner (70%, 0.0001 mg/L) and DP-9 (80%, 0.0001 mg/L), in addition to showing excellent activities against oriental armyworm, fall armyworm, cotton bollworm, corn borer, and mosquito larvae. Furthermore, all of the synthesized compounds also showed broad-spectrum fungicidal activities. CONCLUSION: The insecticidal activities of QAS derivatives of DP-9 were the same as or better than the activity of DP-9. Compounds I-31 and I-34 showed better insecticidal activities against diamondback moth larvae than fluralaner and DP-9, and thus are promising new candidates for insecticide research.


Assuntos
Compostos de Amônio , Inseticidas , Mariposas , Animais , Desenho de Fármacos , Inseticidas/química , Larva , Estrutura Molecular , Relação Estrutura-Atividade
5.
Pest Manag Sci ; 78(3): 982-990, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34761501

RESUMO

BACKGROUND: Plant diseases caused by viruses and fungi have caused great losses to crop quality and yield. The discovery of novel and efficient antiviral and antiphytopathogenic-fungus agents is urgently needed. It is the most important pesticide innovation strategy to find active compounds from natural products. Here, glyantrypine-family alkaloids were taken as the parent structures and a series of their derivatives were designed through molecular splicing, ring expansion, and ring contraction strategies, and synthesized. The anti-tobacco mosaic virus (TMV) activities and antifungal activities of these alkaloids were systematically investigated for the first time. RESULT: The antiviral activities of compounds 7bb, 7bc, 11c, 18b, 18d, 28d, and 28e are equivalent to or better than that of ribavirin (inhibitory rates 39%, 37%, and 40% at 500 µg mL-1 for inactivation, curative, and protection activity in vivo, respectively). Compounds 18d and 28d with good antiviral activities were selected for antiviral mode of action studies, which indicated that these alkaloids could achieve good antiviral effects by inhibiting TMV particle extension during assembly. These compounds also exhibited broad-spectrum fungicidal activities. CONCLUSION: Glyantrypine-family alkaloids and their derivatives were synthesized and evaluated for anti-TMV and fungicidal activities for the first time. Compounds 18d and 28d with excellent antiviral activities and compound 7bc with remarkable fungicidal activity emerged as novel lead compounds. This study lays a foundation for the application of glyantrypine alkaloids in plant protection.


Assuntos
Alcaloides , Fungicidas Industriais , Vírus do Mosaico do Tabaco , Alcaloides/farmacologia , Antivirais/farmacologia , Desenho de Fármacos , Fungos , Fungicidas Industriais/farmacologia , Quinazolinas , Relação Estrutura-Atividade , Triptofano/análogos & derivados
6.
Front Public Health ; 9: 658863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996730

RESUMO

This article employs asymmetric panel causality test to address the causal nexus between energy consumption (EC) and healthcare insurance premiums (IP) for China's different provinces. The empirical results indicate that there exist asymmetric causality runs from positive EC shocks to positive healthcare IPs in Beijing, Hebei, Tianjin, Shanxi, Inner Mongolia, Shaanxi, Gansu, Qinghai, Ningxia, Shandong, Henan, and Anhui. There is no significant link in southern and northeastern provinces mainly because of their industrial structure, high economic development level, strong insurance consciousness, and climate conditions. Therefore, governments should encourage technological innovation and further improve energy efficiency. Meanwhile, we need to optimize EC structure and raise the proportion of renewable energies. The authorities should carry out stricter environmental protection policies and protect people from pollution that comes from fossil fuel burn. The commercial health insurance should be included in the health system and become an important supplement to public health insurance.


Assuntos
Países em Desenvolvimento , Seguro , Pequim , China , Demografia , Humanos
7.
Front Public Health ; 9: 789510, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35004590

RESUMO

This paper discusses the asymmetric effect of air quality (AQ) on stock returns (SR) in China's health industry through the quantile-on-quantile (QQ) regression method. Compared to prior literature, our study provides the following contributions. Government intervention, especially industrial policy, is considered a fresh and essential component of analyzing frameworks in addition to investors' physiology and psychology. Next, because of the heterogeneous responses from different industries to AQ, industrial heterogeneity is thus considered in this paper. In addition, the QQ method examines the effect of specific quantiles between variables and does not consider structural break and temporal lag effects. We obtain the following empirical results. First, the coefficients between AQ and SR in the health service and health technology industries change from positive to negative as AQ deteriorates. Second, AQ always positively influences the health business industry, but the values of the coefficients are larger in good air. In addition, different from other industries, the coefficients in the health equipment industry are negative, but the values of the coefficients change with AQ. The conclusions provide important references for investors and other market participants to avoid biased decisions due to poor AQ and pay attention to government industrial policies.


Assuntos
Poluição do Ar , Humanos , Indústrias , Políticas
8.
Environ Sci Pollut Res Int ; 26(30): 31422-31433, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31478171

RESUMO

This paper offers a perspective for the link between air quality and stock returns in China through quantile Granger causality test. Compared to previous studies, the study makes the following innovations. Given the Chinese government plays an important role in economic development, its industrial policies are regarded as a new indispensable supplement of analysis framework apart from investor mood. Next, due to different reflections from cross-industries for different AQ levels, the industry heterogeneity is further considered. Also, nine industries are chosen as a sample, including environmental protection, wind power equipment, steel, photovoltaic equipment, thermal power, tourism, coal, medical service, and medical equipment. Besides, the quantile Granger causality test is robust to misspecification errors when detecting the potential dependence structure between the variables of air quality and stock returns. The empirical results show that the causal link exists in all industries, except medical service. Meanwhile, this impact presents asymmetrical features that when air quality is unhealthy, it has an influence on stock returns of the remaining eight industries. It can be explained by increasing cortisol level, more stringent environmental protection, and industrial policies. These conclusions have essential implications for market participants due to the fact that air quality generates various influences on the stock market. That is why a sustainable environmental design, strict regulatory framework, and special monitoring activities should be highly regarded in China.


Assuntos
Poluição do Ar/estatística & dados numéricos , Desenvolvimento Econômico/tendências , Indústrias/estatística & dados numéricos , Poluição do Ar/análise , China , Carvão Mineral/análise , Conservação dos Recursos Naturais , Humanos , Investimentos em Saúde , Vento
9.
Physiol Behav ; 105(2): 394-401, 2012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21907224

RESUMO

Motion sickness is caused by exposure to unfamiliar motions and typical symptoms of motion sickness include nausea and vomiting. To observe the metabolic and hormonal differences between nausea/vomiting (NAV) subjects and non-nausea/vomiting (NNV) ones, and to understand how the differences in metabolites and hormones affect the tolerance of organism to acceleration, 60 volunteers were exposed to repetitive acceleration using a 6-degree-of-freedom ship motion simulator. Meanwhile, 36 rats were randomly divided into three groups: an acceleration model group (n=14, exposed to acceleration), insulin group (n=14, intraperitoneal injection of insulin 30 min before exposure to acceleration), and control group (n=8). Gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF/MS) was applied to analyze the serum metabolites in human subjects. Serum glucocorticoid, insulin, and glucagon levels were determined by radioimmunoassay in the NAV and NNV subjects as well as in rats, and serum epinephrine level was determined by ELISA. After acceleration exposure, 9 metabolites, including L-histidine, L-ornithine, L-serine, L-tyrosine, pyroglutamic acid, fumaric acid, urea, n-dodecanoic acid and n-tetradecanoic acid, had different changes in the NAV and NNV groups. The serum levels of 4-hydroxy-L-proline, glucose, oleic acid and urea were significantly higher in the NAV group than in the NNV group after exposure; however, only the elevation degree of serum glucose was significantly greater in the NAV group than in the NNV group (P<0.05). Serum cortisol and epinephrine were increased in both groups. Before exposure, insulin level in the NAV group was significantly lower than that in the NNV group (P<0.05). After rotation exposure, rat serum glucose in the insulin group was significantly lower than that in the acceleration model group (P<0.001), and the motion sickness index was significantly lower than that in the acceleration model group (P<0.05). Our study provides the first evidence that stable glucose level can help to relieve gastrointestinal symptoms in motion sickness, and suggests that acute hyperglycemia is related to gastrointestinal symptoms in motion sickness.


Assuntos
Gastroenteropatias/etiologia , Hiperglicemia/complicações , Hiperglicemia/etiologia , Enjoo devido ao Movimento/complicações , Aceleração/efeitos adversos , Animais , Glicemia , Modelos Animais de Doenças , Hormônios/sangue , Humanos , Hidrocortisona , Masculino , Enjoo devido ao Movimento/sangue , Enjoo devido ao Movimento/etiologia , Análise de Componente Principal , Radioimunoensaio , Ratos , Índice de Gravidade de Doença , Adulto Jovem
10.
Nucl Med Commun ; 32(3): 227-32, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21191313

RESUMO

PURPOSE: To evaluate the effect of using tailored individual doses of radioiodine (¹³¹I) and fine tuning using low-dose antithyroid drug (ATD) in the treatment of Graves' disease, and an attempt to establish a therapeutic strategy that can keep both high rate of euthyroidism and low incidence of hypothyroidism. METHODS: The dose of radioiodine was calculated using the calculated dose formula, and low-dose ATD was used as a way of fine tuning during follow-up. The intended dose of radioiodine was modified according to the patient's age at radioiodine therapy, thyroid size, and duration of hyperthyroidism before radioiodine therapy in the study group; it was set as 2.96 MBq/g of thyroid in the control group. Twenty patients with Graves' disease were nonrandomly assigned to the control group and 98 patients with Graves' disease to the study group. The outcomes, which included euthyroidism, hypothyroidism, and persistent hyperthyroidism, were determined according to the patients' states at the end of follow-up. RESULTS: In the study group, 74 patients (75.5%) achieved the euthyroid state, six patients (6.1%) became hypothyroid, and 18 patients (18.4%) remained hyperthyroid. The rate of euthyroidism was statistically different between the study group and the control group (75.5 vs. 50%, P=0.03). Of 98 patients with Graves' disease in the study group, 19 patients were additionally treated with ATD during follow-up, and 12 patients achieved euthyroidism. In different age groups or duration of hyperthyroidism groups, the rate of euthyroidism was not statistically different among subgroups of goiter grade 1, grade 2, and grade 3 (P>0.05). Similarly, in different age groups or duration of hyperthyroidism groups, the incidence of hypothyroidism was not statistically different among subgroups of goiter grade 1, grade 2, and grade 3 (P>0.05). However, binary logistic regression analysis showed that thyroid size was associated with overtreatment and undertreatment in our study. CONCLUSION: Individual doses of radioiodine, adjusted according to the patient's age, thyroid size, and duration of hyperthyroidism, combined with low-dose ATD for some patients, 1 month or more after radioiodine therapy, was an effective method for treating Graves' disease. Our data showed that using tailored individual doses of radioiodine and fine tuning using low-dose ATD may well be a way to keep both high rate of euthyroidism and low incidence of hypothyroidism. The dose of radioiodine should be decreased a little for small goiter and increased a little for large goiter on the basis of our treatment protocol in future study.


Assuntos
Antitireóideos/uso terapêutico , Doença de Graves/tratamento farmacológico , Doença de Graves/radioterapia , Radioisótopos do Iodo/uso terapêutico , Medicina de Precisão/métodos , Doses de Radiação , Adulto , Idoso , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Análise de Regressão , Resultado do Tratamento , Adulto Jovem
11.
Analyst ; 130(11): 1513-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16222373

RESUMO

A novel, sensitive immunochromatographic electrochemical biosensor (IEB) which combines an immunochromatographic strip technique with an electrochemical detection technique has been demonstrated. The IEB takes advantages of the speed and low-cost of the conventional immunochromatographic test kits and high-sensitivity of stripping voltammetry. Bismuth ions (Bi(3+)) have been coupled with the antibody through the bifunctional chelating agent diethylenetriamine pentaacetic acid (DTPA). After immunoreactions, Bi(3+) was released and quantified by anodic stripping voltammetry at a built-in single-use screen-printed electrode. As an example for the applications of such novel device, the detection of human chorionic gonadotronphin (HCG) in a specimen was performed. This biosensor provides a more user-friendly, rapid, clinically accurate, less expensive immunoassay for such analysis in specimens than currently available test kits.


Assuntos
Técnicas Biossensoriais , Cromatografia/métodos , Imunoquímica/métodos , Metais/análise
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