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1.
Environ Res ; 216(Pt 4): 114838, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36402188

RESUMO

The immobilization of cadmium (Cd(II)) in soil using calcined rectorite (REC) was investigated in this research. The results of immobilization show that a small amount of REC calcined at 700 °C (REC-700 °C) could effectively immobilize 90% of Cd(II) in soil, while the immobilization efficiency of REC only reached 42%. Moreover, the immobilization efficiency of REC calcined at 300 °C and 500 °C (REC-300 °C and REC-500 °C) were lower than REC. To investigate the mechanism, the materials before and after immobilization were fully analyzed by Fourier transform infrared spectroscopy (FT-IR), powdery X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The results indicate that the structure of REC has been changed after calcination at different temperatures and Cd(II) was successfully immobilized on materials. Losing free water, structural water and OH groups respectively, the layer spacing of REC-300 °C and REC-500 °C was shrunk. However, the crystal structure of REC was destroyed after calcination at 700 °C, resulting in the generation of new phases. According to the XRD result, more cadmium hydroxide (Cd(OH)2) were produced on REC-700 °C, indicating that more OH groups were formed during immobilization. Furthermore, Tessier test demonstrates that Cd(II) in soil changed from exchangeable state and water soluble state to carbonate bound state and iron manganese oxide bound state during immobilization. The result of microbial community indicates that REC-700 °C can restore the microbial composition of Cd(II)-contaminated soil. The effects of pH, freeze-thaw, REC dosage, and initial heavy metal concentration were also evaluated to provide a theoretical basis for the subsequent application of the material in the remediation of contaminated soil.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Solo/química , Poluentes do Solo/análise , Temperatura , Espectroscopia de Infravermelho com Transformada de Fourier , Água/análise
2.
Emotion ; 24(2): 412-430, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37535566

RESUMO

Awe is theoretically proposed as a meaning-making emotion. However, empirical evidence has shown that awe has mixed effects on meaning in life. The explanations for such complicated results have been limited. To fill this gap, in this research, we aimed to clarify how and when awe contributes to meaning in life. In six studies (N = 1,115), we examined the indirect effect of awe on meaning in life through authentic-self pursuit as well as trait authenticity's moderating effect on this indirect effect. We consistently found a positive indirect effect of awe on meaning in life via authentic-self pursuit (Studies 1-3 and Study 5), which arised beyond happiness and self-smallness (Studies 2a, 2b, and 3) and also held for awe brought on by a threatening experience (Study 3). Moreover, we found that manipulating authentic-self pursuit improved meaning in life (Study 4). Importantly, the main effect of awe on meaning in life and indirect effect of awe on meaning in life through authentic-self pursuit were significant for those with low to average rather than high trait authenticity (Study 5). These findings facilitate the understanding of awe as a meaning-making emotion. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Emoções , Felicidade , Humanos
3.
ISA Trans ; 128(Pt B): 109-122, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34955240

RESUMO

This paper investigates the problem of finite-time H∞ synchronization (H∞FTS) for complex dynamical networks (CDNs) with time-varying delays(TVDs) and unknown internal coupling matrices. External disturbances are also considered into this model. By applying the adaptive control theory, this paper presents the adaptive control method to solve the H∞FTS of CDNs with external disturbances and TVDs. Some criteria are obtained by utilizing appropriate adaptive controllers and devising a special Lyapunov-Krasovskii function (LKF), which ensure the H∞FTS of CDNs based on passivity theory. Finally, using some effective mathematical techniques, comparative numerical example and Chua's circuit system are used to explain the advantages and applicability of the results and approaches.

4.
J Agric Food Chem ; 70(50): 15693-15702, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36479881

RESUMO

Plant diseases seriously affect the growth of crops and the quality and yield of agricultural products. The search for plant-derived pesticide candidates based on natural products is a hot topic of current research. Marine natural products almazoles C-D were efficiently prepared and selected as the lead compounds in this work. Two series of almazole derivatives were designed and synthesized, and their antiviral and fungicidal activities were systematically evaluated. The results of anti-tobacco mosaic virus (anti-TMV) activity showed that almazoles C-D and their derivatives had good anti-TMV activities. Compounds 6, 15, 16a, 16b, 16g, 16l, 16n, 20a, 20d, 20i, and 20n exhibited better anti-TMV activities than the commercial antiviral agent ribavirin. Anti-TMV mechanism studies showed that compound 16b could induce the polymerization of 20S CP (coat protein, CP), thereby affecting the assembly of TMV virus particles. Molecular docking results showed that compounds 15, 16b, and 20n could combine with amino acid residues through hydrogen bonds to achieve an excellent anti-TMV effect. In addition, most of the almazole derivatives were found to have broad-spectrum fungicidal activities against eight kinds of plant pathogens (Fusarium oxysporum f. sp. cucumeris, Cercospora arachidicola Hori, Physalospora piricola, Rhizoctonia cerealis, Alternaria solani, Pyricularia grisea, Phytophthora capsici, and Sclerotinia sclerotiorum). This study provides an important evidence for the research and development of almazole alkaloids containing indole and oxazole structural groups as novel agrochemicals.


Assuntos
Produtos Biológicos , Vírus do Mosaico do Tabaco , Antivirais/farmacologia , Antivirais/química , Relação Estrutura-Atividade , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Simulação de Acoplamento Molecular , Ribavirina/farmacologia , Desenho de Fármacos
5.
Pest Manag Sci ; 77(10): 4691-4700, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34132452

RESUMO

BACKGROUND: Plant diseases have been gripping agricultural production, seriously affecting the growth and yields of crops. Marine natural products are an important source for novel drugs discovery. In this work, pityriacitrin marine alkaloids were selected as the parent structures. A series of pityriacitrin alkaloid analogues were rationally designed, synthesized and evaluated for their antiviral activities and fungicidal activities. RESULT: Most of these compounds were demonstrated to have higher antiviral activities than ribavirin. Particularly, compounds 3a, 3e, 8f, 8g, and 9g displayed higher anti-TMV activities than ningnanmycin at 500 µg·mL-1 . Mechanism research revealed that 3a could bind to TMV CP with an excellent affinity (Ka  = 8.67 × 106 L·mol-1 ), thus interfere with the assembly of virus particles. These alkaloids also showed broad-spectrum fungicidal activities against eight kinds of phytopathogenic fungi. Compound 5f with 1.43-3.84 µg·mL-1 EC50 value against three fungi emerged as a new fungicidal candidate. CONCLUSION: Pityriacitrin alkaloids and their derivatives were synthesized and evaluated for anti-TMV and fungicidal activities for the first time. Compounds 3a and 5f with excellent activities emerged as new candidates for antiviral research and fungicidal research, respectively. Current work provided a new idea for the molecular design and development of novel plant virus and fungi inhibitors in the future. © 2021 Society of Chemical Industry.


Assuntos
Alcaloides , Vírus do Mosaico do Tabaco , Alcaloides/farmacologia , Antivirais/farmacologia , Desenho de Fármacos , Fungos , Alcaloides Indólicos , Relação Estrutura-Atividade
6.
Artigo em Zh | MEDLINE | ID: mdl-17639710

RESUMO

Toxoplasma gondii infection during pregnancy can result in abortion, premature delivery, fetal death, deformity, and impact the physical and intellectual development of the newborns. This is an investigation on the consequences of pregnancy in Toxoplasma gondii-infected women, the development of their babies, and the effect of pyrimethamine treatment during 1990-1996 in Baoding City.


Assuntos
Desenvolvimento Infantil/fisiologia , Desenvolvimento Fetal/fisiologia , Toxoplasmose Congênita/fisiopatologia , Adulto , Antiprotozoários/uso terapêutico , China , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Gravidez , Resultado da Gravidez , Pirimetamina/uso terapêutico , Toxoplasmose Congênita/tratamento farmacológico , Toxoplasmose Congênita/parasitologia
7.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 27(5): 555-7, 559, 2015 Oct.
Artigo em Zh | MEDLINE | ID: mdl-26930953

RESUMO

Toxoplasma gondii is an opportunity cellular parasite, related to the infection of various animals and human beings and severely impairing agriculture and human health. Because of the complexity of T. gondii life cycle, its different biological characteristics, and multifarious pathogenesis, there are no specific treatment and preventive medicines at present. Chinese herbal medicine can balance "yin-yang" and regulate the immunity and its side-effect is slight. Now, it has been a hot topic of the research on effective and secure medicines in anti-toxoplasmosis. This paper summarizes and analyzes the curative effect and mechanism of anti-Toxoplasma Chinese herbal medicine, such as Scutellaria baicalensis, Inontus obliquus polysaccharide, Radix glycyrrhizae, pumpkin seeds, and Semen arecae.


Assuntos
Antiprotozoários/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Toxoplasma/efeitos dos fármacos , Toxoplasmose/tratamento farmacológico , Animais , Pesquisa Biomédica/métodos , Pesquisa Biomédica/tendências , Humanos , Fitoterapia/métodos , Fitoterapia/tendências , Plantas Medicinais/química , Toxoplasma/fisiologia , Toxoplasmose/parasitologia
8.
Artigo em Zh | MEDLINE | ID: mdl-25345174

RESUMO

OBJECTIVE: To evaluate the molluscicidal effect of black plastic mulching in mountainous areas of Yunnan Province. METHODS: In Leqiu Village, Nanjian County, Yunnan Province, the terraced fields with Oncomelania hupensis snails were divided into A, B, C, D, E groups, and of which, A, B, C, D groups, as the experimental groups, were administered with simple black plastic mulching for 30 days, 60 days, 90 days and 120 days respectively; Group E, as the control group, was administered with 50% niclosamide ethanolamine salt wettable powder spraying. RESULTS: In Group C and D (simple black film mulching for 90 days and 120 days), no snails were found after the administration, the average density of living snails decreased by 100%, and the cost of one year was similar to that of the control group. CONCLUSION: The molluscicidal effect of black plastic mulching is good in mountainous areas.


Assuntos
Controle de Doenças Transmissíveis/métodos , Caramujos , Solo , Animais , China , Controle de Doenças Transmissíveis/economia , Análise Custo-Benefício , Temperatura
9.
Peptides ; 31(1): 22-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19854232

RESUMO

Scorpion has an innovative venom gland, which is an important determinant in contributing to its successful survival for more than 400 million years. Scorpion venom contains a diversity of bioactive peptides, which represent a tremendous hitherto unexplored resource for use in drug design and development. Here, StCT1, a new antimicrobial peptide gene, was screened and isolated from the venomous gland cDNA library of the scorpion Scorpiops tibetanus. The full-length cDNA of StCT1 is 369 nucleotides encoding the precursor that contains a putative 24-residue signal peptide, a presumed 14-residue mature peptide, and an uncommon 37-residue acidic propeptide at the C-terminus. The minimal inhibitory concentrations (MICs) of the synthetic StCT1 peptide against Staphylococcus aureus and Micrococcus luteus were 12.5microg/ml and 100microg/ml, respectively. The MICs of StCT1 against clinical antibiotics-resistant bacterial strains, were 50-250microg/ml, 2-40 folds lower than those of penicillin. These results show that the antimicrobial peptide encoded by StCT1 gene from the venom of the scorpion S. tibetanus is a potential anti-infective polypeptide or lead compound, especially for treating antibiotics-resistant pathogens.


Assuntos
Anti-Infecciosos , Peptídeos Catiônicos Antimicrobianos , Peptídeos/genética , Peptídeos/metabolismo , Peptídeos/farmacologia , Venenos de Escorpião/química , Escorpiões/química , Sequência de Aminoácidos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sequência de Bases , Clonagem Molecular , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Dados de Sequência Molecular , Venenos de Escorpião/genética , Venenos de Escorpião/metabolismo , Venenos de Escorpião/farmacologia , Alinhamento de Sequência , Staphylococcus aureus/efeitos dos fármacos
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