Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Environ Res ; 244: 117912, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38097058

RESUMO

Energy transition policies are of great significance in adjusting the structure of energy supply and demand and coping with climate change. The new energy demonstration city pilot (NEDCP) policy, as an important pilot project in China's energy transition process, lacks a scientific assessment of the carbon reduction effect of the NEDCP policy and an in-depth explanation of the mechanism of the NEDCP. Based on panel data of 209 Chinese cities at the prefectural and higher levels from 2007 to 2019, this study takes the NEDCP policy as a quasi-natural experiment, using a difference-in-differences model combined with firm-level data to identify the impact of the NEDCP policy on urban carbon dioxide (CO2) emissions. This study analyzes the impact of heterogeneity of urban characteristics on the policy effect from multiple perspectives, and further investigates its mechanism. The conclusions are shown in the following aspects. (1) The implementation of the NEDCP policy decreases urban CO2 emissions significantly. Meanwhile, a series of robustness tests, including the instrumental variables method, propensity score matching difference-in-differences method, placebo test, exclusion of policy interference test, and machine learning method, support this conclusion. (2) The NEDCP policy achieves carbon reduction effects mainly through scale and structure effects. (3) The results of the heterogeneity test show that the NEDCP policy is more effective in cities with higher administrative levels, energy-demanding cities, cities in the southeast of Hu-line, and cities with a higher degree of nationalization. Therefore, the Chinese government should summarize the implementation experience of the NEDCP policy and expand its scope of application. The evaluation of the NEDCP policy in China has important reference value for the energy transition of other developing countries.


Assuntos
Dióxido de Carbono , Políticas , Cidades , Projetos Piloto , China , Desenvolvimento Econômico
2.
J Environ Manage ; 364: 121468, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38879969

RESUMO

Both market-oriented and government-led spatial agglomeration of factories profoundly affect China's carbon emission intensity. However, few studies have comprehensively examined the effect of spatial agglomeration of factories driven by different motivations on carbon emission intensity, and often ignore the moderating effect of local government attention to the environment. This study attempts to incorporate market-oriented and government-led spatial agglomeration of factories into the same analytical framework and examine their interaction effects on carbon emission intensity. We first calculate an Agglomeration Index based on the geographic coordinates of micro-factories to measure market-oriented agglomeration of factories, and take development zone policies as a proxy for government-led agglomeration of factories. Based on city-level data from 1998 to 2013, we empirically analyze their impacts on carbon emission intensity and further explore regional heterogeneity and mechanisms. The results show that both the market-oriented and government-led spatial agglomeration of factories can significantly reduce carbon emission intensity through scale effect, innovation effect and structure effect. However, the agglomeration of factories caused by government forces has weakened the original effect of market-oriented agglomeration of factories in reducing carbon emission intensity. Heterogeneity analysis indicates that government-led agglomeration of factories is more effective in reducing carbon emission intensity in less-developed regions. Furthermore, the improvement of the governments' attention to the environment can further exert the positive effect of spatial agglomeration of factories on carbon emission intensity. Our study deepens the understanding of the effects of spatial agglomeration of factories caused by different motivations, and provides a reference for China and other developing countries to formulate relevant policies for reducing carbon emission intensity.


Assuntos
Carbono , China , Carbono/análise , Governo
3.
Crit Rev Food Sci Nutr ; : 1-13, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37310013

RESUMO

Diabetes is one of the fastest-growing and most widespread diseases worldwide. Approximately 90% of diabetic patients have type 2 diabetes. In 2019, there were about 463 million diabetic patients worldwide. Inhibiting the dipeptidyl peptidase IV (DPP-IV) and α-glucosidase activity is an effective strategy for the treatment of type 2 diabetes. Currently, various anti-diabetic bioactive peptides have been isolated and identified. This review summarizes the preparation methods, structure-effect relationships, molecular binding sites, and effectiveness validation of DPP-IV and α-glucosidase inhibitory peptides in cellular and animal models. The analysis of peptides shows that the DPP-IV inhibitory peptides, containing 2-8 amino acids and having proline, leucine, and valine at their N-terminal and C-terminal, are the highly active peptides. The more active α-glucosidase inhibitory peptides contain 2-9 amino acids and have valine, isoleucine, and proline at the N-terminal and proline, alanine, and serine at the C-terminal.

4.
Chem Biodivers ; 20(12): e202301298, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37990607

RESUMO

Since ancient times, China has used natural medicine as the primary way to combat diseases and has a rich arsenal of natural medicines. With the progress of the times, the extraction of bioactive molecules from natural drugs has become the new development direction for natural medicines. Among the numerous natural drugs, Schisandrin C (Sch C), derived from Schisandra Chinensis (Turcz.) Baill. It has excellent potential for development and has been shown to possess various pharmacological properties, including hepatoprotective, antitumor and anti-inflammatory activities. Based on the biological properties of hepatoprotection, scholars have explored Sch C and its synthetic products in depth; some studies have shown that pentosidine has the effect of improving the symptoms of liver fibrosis and reducing the concentration of alanine transaminase (ALT) and aspartate aminotransferase (AST) in the serum of rats, which is an essential inspiration for the development of anti-liver fibrosis drugs. But more in vivo and ex vivo studies still need to be included. This paper focuses on Sch C's extraction and synthesis, biological activities and drug development progress. The future application prospects of Sch C are discussed to perfect its development work further.


Assuntos
Lignanas , Compostos Policíclicos , Schisandra , Ratos , Animais , Lignanas/farmacologia , Compostos Policíclicos/farmacologia , Ciclo-Octanos/farmacologia , Relação Estrutura-Atividade
5.
J Psycholinguist Res ; 52(3): 957-974, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36445529

RESUMO

The language used to present an argument has long been argued to influence people's reaction to that argument. This study examined how language and grammatical structure influenced response to health-related dilemmas. We investigated whether medical students' willingness to receive a medical treatment or to take an action (regarding advancing one's own health or other people's health) was influenced by the language (first versus foreign) and the grammatical structures (modifiers and quantifiers) used. Saudi medical students (N = 368) read health-related dilemmas using different adverbial modifiers and quantifiers in Arabic or in English. The participants were randomly assigned to one of four conditions: Arabic with high certainty (i.e., very-modifier and all-quantifier), Arabic with low certainty (no very-modifier and some-quantifier), English with high certainty, and English with low certainty. The results showed that the participants were susceptible to a foreign language effect, but not to a grammatical structure effect. We discuss the implications of these results in relation to how different health-scenarios may affect decision making for health professionals.


Assuntos
Idioma , Leitura , Humanos
6.
Sensors (Basel) ; 22(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36236667

RESUMO

This paper presents a fast design optimization using an effective characteristic analysis for linear permanent magnet motors (LPMMs) with techniques for improving motor performance such as using an auxiliary tooth, permanent magnet (PM) skew, and overhang structures. These techniques have different effects on the characteristics of the LPMM depending on the combinations of each other, resulting in complexity in the design optimization process. In particular, the three-dimensional (3-D) effect of the PM skew and overhang structure takes a lot of time to be analyzed. To deal with this problem, an effective magnetic field analysis method and a novel optimization algorithm are proposed. Preferentially, the field reconstruction method is used for a fast and accurate evaluation of the magnetic field of the LPMM. In the proposed magnetic field analysis method, the change of magnetic field distribution due to the addition of an auxiliary tooth is predicted, and the 3-D magnetic field effect of PM skew and overhang structure is considered. By reducing the computational burden in the magnetic field analysis, the electromagnetic characteristics of LPMMs can be calculated quickly, such as detent force, end force, thrust force, and back-EMF. The effect of the auxiliary tooth and overhang structure on the optimal PM skew length is investigated with comparative study results. Subsequently, the proposed optimization algorithm has the advantage of reducing time cost by providing multimodal optimization and robustness evaluation of local peaks at the same time. The proposed method is verified via comparison with finite element analysis and experimental results.


Assuntos
Algoritmos , Imãs , Fenômenos Eletromagnéticos , Análise de Elementos Finitos , Campos Magnéticos
7.
Mol Divers ; 24(3): 753-761, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31321647

RESUMO

A novel one-pot four-component reaction of an aldehyde, malononitrile, hydrazine and 4,4-dimethyl-3-oxopentanenitrile is described. As regio- and chemoselective products, 7-amino-2-(tert-butyl)-5-aryl-4,5-dihydropyrazolo[1,5-a]pyrimidine-6-carbonitriles are formed during the course of the reaction.


Assuntos
Nitrilas/química , Nitrilas/síntese química , Pirazóis/química , Técnicas de Química Sintética , Cinética , Estereoisomerismo
8.
Subcell Biochem ; 71: 127-59, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26438264

RESUMO

It is commonly assumed that the structure of water at a lipid-water interface is influenced mostly in the first hydration layer. However, recent results from different experimental methods show that perturbation extends through several hydration layers. Due to its low light penetration depth, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy is specifically suited to study interlamellar water structure in multibilayers. Results obtained by this technique confirm the long-range water structure disturbance. Consequently, in confined membrane environments nearly all water molecules can be perturbed. It is important to note that the behavior of confined water molecules differs significantly in samples prepared in excess water and in partially hydrated samples. We show in what manner the interlamellar water perturbation is influenced by the hydration level and how it is sequentially modified with a step-by-step dehydration of samples either by water evaporation or by osmotic pressure. Our results also indicate that besides different levels of hydration the lipid-water interaction is modulated by different lipid headgroups and different lipid phases as well. Therefore, modification of interlamellar water properties may clarify the role of water-mediated effects in biological processes.


Assuntos
Lipídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química
9.
Mar Drugs ; 14(6)2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27322290

RESUMO

The present study is focused on the intestinal absorption of sea cucumber saponins. We determined the pharmacokinetic characteristics and bioavailability of Echinoside A and Holotoxin A1; the findings indicated that the bioavailability of Holotoxin A1 was lower than Echinoside A. We inferred that the differences in chemical structure between compounds was a factor that explained their different characteristics of transport across the intestine. In order to confirm the absorption characteristics of Echinoside A and Holotoxin A1, we examined their transport across Caco-2 cell monolayer and effective permeability by single-pass intestinal perfusion. The results of Caco-2 cell model indicate that Echinoside A is transported by passive diffusion, and not influenced by the exocytosis of P-glycoprotein (P-gp, expressed in the apical side of Caco-2 monolayers as the classic inhibitor). The intestinal perfusion also demonstrated well the absorption of Echinoside A and poor absorption of Holotoxin A1, which matched up with the result of the Caco-2 cell model. The results demonstrated our conjecture and provides fundamental information on the relationship between the chemical structure of these sea cucumber saponins and their absorption characteristics, and we believe that our findings build a foundation for the further metabolism study of sea cucumber saponins and contribute to the further clinical research of saponins.


Assuntos
Absorção Intestinal/fisiologia , Saponinas/metabolismo , Pepinos-do-Mar/metabolismo , Stichopus/metabolismo , Animais , Disponibilidade Biológica , Transporte Biológico/fisiologia , Células CACO-2 , Linhagem Celular Tumoral , Glicosídeos/metabolismo , Holoturina/análogos & derivados , Holoturina/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Masculino , Ratos , Ratos Wistar , Saponinas/farmacocinética , Triterpenos/metabolismo
10.
Chem Biol Drug Des ; 103(1): e14366, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776270

RESUMO

Epigenetic regulation of genes through posttranslational regulation of proteins is a well-explored approach for disease treatment, particularly in cancer chemotherapy. Histone deacetylases have shown significant potential as effective drug targets in therapeutic studies aiming to restore epigenetic normality in oncology. Besides their role in modifying histones, histone deacetylases can also catalyze the deacetylation of various nonhistone proteins and participate in the regulation of multiple biological processes. This paper provides a review of the classification, structure, and functional characteristics of the four classes of human histone deacetylases. The increasing abundance of structural information on HDACs has led to the gradual elucidation of structural differences among subgroups and subtypes. This has provided a reasonable explanation for the selectivity of certain HDAC inhibitors. Currently, the US FDA has approved a total of six HDAC inhibitors for marketing, primarily for the treatment of various hematological tumors and a few solid tumors. These inhibitors all have a common pharmacodynamic moiety consisting of three parts: CAP, ZBG, and Linker. In this paper, the structure-effect relationship of HDAC inhibitors is explored by classifying the six HDAC inhibitors into three main groups: isohydroxamic acids, benzamides, and cyclic peptides, based on the type of inhibitor ZBG. However, there are still many questions that need to be answered in this field. In this paper, the structure-functional characteristics of HDACs and the structural information of the pharmacophore model and enzyme active region of HDAC is are considered, which can help to understand the inhibition mechanism of the compounds as well as the rational design of HDACs. This paper integrates the structural-functional characteristics of HDACs as well as the pharmacophore model of HDAC is and the structural information of the enzymatic active region, which not only contributes to the understanding of the inhibition mechanism of the compounds, but also provides a basis for the rational design of HDAC inhibitors.


Assuntos
Inibidores de Histona Desacetilases , Neoplasias , Humanos , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Epigênese Genética , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Histonas/metabolismo
11.
Curr Dev Nutr ; 8(6): 103765, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38993332

RESUMO

Background: This study examines the impact of socioeconomic factors on calorie intake and macronutrient composition at the household level in Pakistan from 2006 to 2016, using data from the Household Integrated Income and Consumption Survey (HIICS). By applying a copula-based decomposition method, it identifies key drivers such as urbanization, household size, paternal education, income, and cultivation, highlighting their roles in dietary changes and implications for public health. The findings are crucial for understanding nutritional shifts and addressing non-communicable diseases. Objectives: This study was conducted to assess the socioeconomic changes in total calorie intake per capita and calories obtained from macronutrients (fat, protein, and carbohydrates) at the household level in Pakistan. Methods: : Cross-sectional data were taken from 2 national-level surveys published by the Pakistan Bureau of Statistics: the Household Integrated Economic Survey 2006 (14,948 households) and the Household Integrated Income and Consumption Survey 2016 (7842 households). Participants were from all 4 provinces of Pakistan. A copula-based decomposition method was applied to decompose the 10-y change in the distribution (mean, median, and quartiles) of the total calorie intake per capita and calories obtained from macronutrients. Results: The estimated results of decomposition revealed that total calorie intake per capita has increased on average and in the considered quartiles. The calories obtained from fat and carbohydrates have increased, whereas calories from protein have decreased, according to the distribution of the mean and quartile. The composition effect was negative for all outcome variables, and the main drivers of the composition effect were urbanization, household size, paternal education, income, and cultivation for all outcome variables. Conclusions: Household size and income are the most important covariates in an increase of total calories per capita and consumption of macronutrients, but urbanization, paternal education, and cultivation contribute negatively to the composition effect. Such findings are very important to inform researchers about nutritional change at the national level because the correlation between dietary change and risk factors for noncommunicable diseases such as heart disease and obesity is very strong.

12.
Curr Med Chem ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347784

RESUMO

Antioxidant research has recently become a popular topic. Medicinal plants are important sources of novel active compounds. Diarylheptanoids, a typical family of secondary plant metabolites, are of great interest owing to their extensive spectrum of biological activities. They possess a unique 1,7-diphenylmethane structural skeleton. Thus, this review summarizes the natural linear or macrocyclic diarylheptanoids with antioxidant activity in the last two decades. In addition, the relationships between the structural characteristics of natural diarylheptanoids and their antioxidant capacity were also discussed. All the available data highlight the potential of natural diarylheptanoids as novel antioxidants.

13.
Int J Biol Macromol ; 258(Pt 2): 128992, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38151085

RESUMO

The emulsifying properties of emulsions are significantly influenced by the structural properties of octenyl succinic anhydride (OSA) starch. The purpose of this work was to elucidate the effect of the structure of OSA starch on its performance as an emulsifier to stabilize Pickering high-internal-phase emulsions (HIPEs). The degrees of substitution (DS) of the three OSA starches were 0.0137, 0.0177 and 0.0236, and their degrees of branching (DB) were 13.96 %, 14.20 % and 14.32 % measured by 1H NMR, which were sequentially labeled as OSA1, OSA2, and OSA3. The OSA3 starch with higher DS and DB had a lower critical micelle concentration (CMC) (0.11 mg/mL). Its emulsification activity (EAI) and emulsion stability (ES) were 61.8 m2/g and 72.5 min, respectively, which were higher than OSA1 and OSA2 starches. The contact angle of the three OSA starches increased from 45.35° to 80.03° with increasing DS and DB. Therefore, it is hypothesized that OSA3 starches have better emulsification properties. The results of physical stability of HIPEs confirmed the above results. These results indicated that DS and DB have a synergistic effect on emulsion properties, and OSA starch with higher DS and DB values were more conducive to the construction of stable HIPEs systems.


Assuntos
Amido , Anidridos Succínicos , Emulsões/química , Anidridos Succínicos/química , Tamanho da Partícula , Amido/química
14.
Environ Sci Pollut Res Int ; 31(7): 10133-10147, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36787071

RESUMO

Few studies provide direct evidences that agricultural fiscal affects agricultural carbon intensity. This study tries to fill this gap. Using panel data of 30 provinces in China from 2005 to 2019, we conclude that agricultural fiscal expenditures significantly reduce agricultural carbon intensity. The result is still robust after employing the provincial agricultural leaders' birthplace information as an instrumental variable. Further study shows that the negative effect of agricultural fiscal expenditures on agricultural carbon intensity is more pronounced in regions with less corruption and is also more visible in central, western, and inland regions than other areas. For this effect, agricultural technological improvement and structure optimization are possible channels, but not operation scale expansion. Interestingly, although agricultural fiscal expenditures reduce the local agricultural carbon intensity, neighbor regions' carbon intensities are increased due to fiscal rivalry.


Assuntos
Carbono , Gastos em Saúde , Carbono/análise , Agricultura , Tecnologia , China , Desenvolvimento Econômico , Dióxido de Carbono
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123771, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38150988

RESUMO

Photophysical behavior of two D - π - A+ cationic compounds with the same furyl bridge and nicotinamidine group as an electron acceptor moiety and two electron donating groups, namely methoxy (I) and N,N-dimethylamino (II) groups was examined using steady-state and time-resolved techniques in variety of solvents. Time-dependent density functional theory (TDDFT) calculations were performed in some representative solvents and compared with the experimental results. Steady state and time-resolved studies in different solvents reveal that fluorescence emission of (I) is ascribed to an emission from an excited state (ICT) with higher dipole moment than the ground state while the emission of (II) is a dual emission from a state with high charge transfer nature (ICT) in addition to the locally excited state (LE). The fluorescence emission spectra of (II) were found to depend on the excitation wavelength and an increase in the excitation wavelength led to the formation of a longer wavelength emission band with lower quantum yield. It has also been found that the fluorescence excitation spectra were dependent on the emission wavelength. The effect of solvent on the nature of dual emission was examined. Correlation of the photophysical properties of the excited states of (I) and (II) with the solvent polarity, ε, reveals the charge transfer nature of (I) and the long wavelength emission band of (II), while their correlation with the solvent polarity parameter (ETN) shows two different trends when the solvents are divided to aprotic and protic solvents. For precise investigation of the impact of each solvent parameter on each photophysical property, Catalán's and Laurence's four parametric linear solvation energy relationships were studied. We have found that the non-specific interactions of the solvent are primarily responsible for controlling the photophysical properties, as demonstrated by Catalán's and Laurence's treatments. DFT and TDDFT calculations were used to anticipate the dipole moments in the ground and excited states and geometry of both states.

16.
Adv Mater ; : e2403624, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129355

RESUMO

Interplay between magnetism and photoelectric properties introduces the effective control of photoresponse in optoelectronic devices via magnetic field, termed as magneto-photoresponse. It enriches the application scenarios and shows potential to construct in-sensor vision systems for artificial intelligence with gate-free architecture. However, achieving a simultaneous existence of room-temperature magnetism and notable photoelectric properties in semiconductors is a great challenge. Here, the room-temperature magneto-photoresponse is accomplished in all-2D optoelectronic devices, employing 2D ferromagnet Fe3GaTe2 as the source and drain, with WSe2 forming the channel. The interplay between room-temperature magnetism and photoelectric properties is realized by introducing the unique magneto-band structure effect from 2D interface, resulting in magneto-tunable charge transfer between Fe3GaTe2 and WSe2. The photocurrent in this 2D optoelectronic device exhibits robust response to both the direction and amplitude of external magnetic fields. Utilizing constructed 2D optoelectronic devices with magneto-photoresponse, traditional gate-controlled phototransistors are replaced and a prototype in-sensor vision system with visual adaptation, significantly improving the recognition accuracy to over four times in low-contrast environments is established. These findings pave a way for achieving high-temperature magneto-photoresponse, thereby guiding the construction of robust in-sensor vision systems toward high performance and broad applications.

17.
Sci Total Environ ; 903: 166142, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37574061

RESUMO

Adsorption technology has been widely developed to control environmental pollution, which plays an important role in the sustainable development of modern society. Calcium carbonate (CaCO3) is characterized by its flexible pore design and functional group modification, which meet the high capacity and targeting requirements of adsorption. Therefore, its charm of "small materials for great use" makes it a suitable candidate for adsorption. Firstly, we comprehensively review the research progress of controlled synthesis and surface modification of CaCO3, and its application for adsorbing contaminants from water and air. Then, we systematically examine the structure-effect relationship between CaCO3 adsorbents and contaminants, while also intrinsic mechanism of remarkable capacity and targeted adsorption. Finally, from the perspective of material design and engineering application, we offer insightful discussion on the prospects and challenges of calcium carbonate adsorbents, providing a valuable reference for the further research in this field.

18.
Environ Sci Pollut Res Int ; 30(50): 108706-108719, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37752402

RESUMO

Both indoor and outdoor contamination continually contain benzene vapor. It has primary concerns about long-term health risks to the living environment. Benzene is a crucial airborne pollutant in the environment due to its apparent acute toxicity, high volatility, and poor degradability. It is especially urgent to restrain benzene emissions due to the persistent concentration increase and stringent processes. Benzene adsorption is a highly efficient mechanism with low cost, low energy consumption, and a simple process. In this study, biomass-derived porous carbon materials (TCACs) were synthesized by pyrolysis activation combined with H3PO4, HNO3, and HCl. TCAC44 has the best activation conclusion, showing that surface area and pore volume were 1107 m2/g and 0.58 cm3/g treated with H3PO4 and so was chosen for subsequent benzene adsorption/desorption tests. The adsorption capacities of benzene for TCAC44 were increased from 58 mg/g for 35 °C + 95% RH to 121 mg/g for 25 °C + 15% RH and presented a higher adsorption capacity of benzene than TCAC101 and TCAC133. Otherwise, well recyclability of TCAC44 was revealed as the benzene adsorption capacity reductions were 22.49% after five adsorption-desorption cycles. Furthermore, the present study established the property-application relationships to promote and encourage future research on the newly synthesized innovative TCAC44 for benzene removal.


Assuntos
Benzeno , Compostos Orgânicos Voláteis , Carvão Vegetal , Lignina , Adsorção , Gases
19.
Carbohydr Polym ; 321: 121284, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739497

RESUMO

Polysaccharide-based gold nanomaterials have attracted great interest in biomedical fields such as cancer therapy and immunomodulation due to their prolonged residence time in vivo and enhanced immune response. This review aims to provide an up-to-date and comprehensive summary of polysaccharide-based Au NMs synthesis, including mechanisms, polysaccharide structure-effects, and anticancer activity. Firstly, research progress on the synthesis mechanism of polysaccharide-based Au NMs was addressed, which included three types based on the variety of polysaccharides and reaction environment: breaking of glycosidic bonds via Au (III) or base-mediated production of highly reduced intermediates, reduction of free hydroxyl groups in polysaccharide molecules, and reduction of free amino groups in polysaccharide molecules. Then, the potential effects of polysaccharide structure characteristics (molecular weight, composition of monosaccharides, functional groups, glycosidic bonds, and chain conformation) and reaction conditions (the reaction temperature, reaction time, pH, concentration of gold precursor and polysaccharides) on the size and shape of Au NMs were explored. Finally, the current status of polysaccharide-based Au NMs cancer therapy was summarized before reaching our conclusions and perspectives.


Assuntos
Glicosídeos , Neoplasias , Humanos , Ouro/farmacologia , Imunomodulação , Polissacarídeos/farmacologia , Neoplasias/tratamento farmacológico
20.
Sci Total Environ ; 870: 161950, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36740075

RESUMO

Marine shell resources have received great attention from researchers owing to their unique merits such as high hardness, good toughness, corrosion resistance, high adsorption, and bioactivity. Restricted by the level of comprehensive utilization technology, the utilization rate of shells is extremely low, resulting in serious waste and pollution. The research shows that the unique brick-mud structure of shells makes them have diverse and good functional characteristics, which guides them to have great utilization potential in different fields. Hence, this review highlights the constitutive relationship between microstructure-function-application of shells (e.g., gastropods, cephalopods, and amniotes), and the comprehensive applications and development ideas in the fields of biomedicine, adsorption enrichment, pHotocatalysis, marine carbon sink, and environmental deicer. It is worth mentioning that marine shells are currently well developed in three areas: bone repair, health care and medicinal value, and drug carrier, which together promote the progress of biomedical field. In addition, an in-depth summary of the application of marine shells in the adsorption and purification of various impurities such as crude oil, heavy metal ions and dyes at low-cost and high efficiency is presented. Finally, by integrating thoughts and approaches from different applications, we are committed to providing new pathways for the excavation and future high-value of shell resources, clarifying the existing development stages and bottlenecks, promoting the development of related technology industries, and achieving the synergistic win-win situation of economic and environmental benefits.


Assuntos
Gastrópodes , Metais Pesados , Petróleo , Animais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA