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1.
J Hazard Mater ; 475: 134917, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38889472

RESUMEN

Crystal facet and defect engineering are crucial for designing heterogeneous catalysts. In this study, different solvents were utilized to generate NiO with distinct shapes (hexagonal layers, rods, and spheres) using nickel-based metal-organic frameworks (MOFs) as precursors. It was shown that the exposed crystal facets of NiO with different morphologies differed from each other. Various characterization techniques and density functional theory (DFT) calculations revealed that hexagonal-layered NiO (NiO-L) possessed excellent low-temperature reducibility and oxygen migration ability. The (111) crystal plane of NiO-L contained more lattice defects and oxygen vacancies, resulting in enhanced propane oxidation due to its highest O2 adsorption energy. Furthermore, the higher the surface active oxygen species and surface oxygen vacancy concentrations, the lower the C-H activation energy of the NiO catalyst and hence the better the catalytic activity for the oxidation of propane. Consequently, NiO-L exhibited remarkable catalytic activity and good stability for propane oxidation. This study provided a simple strategy for controlling NiO crystal facets, and demonstrated that the oxygen defects could be more easily formed on NiO(111) facets, thus would be beneficial for the activation of C-H bonds in propane. In addition, the results of this work can be extended to the other fields, such as propane oxidation to propene, fuel cells, and photocatalysis.

2.
Environ Sci Pollut Res Int ; 31(24): 35498-35518, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38724848

RESUMEN

The rapid economic development leads to excessive consumption of fossil energy, resulting in a large number of carbon emissions, which makes the sustainable development of China's economy and society face great challenges. Under the background of global warming and environmental deterioration, developing low-carbon economy has become an inevitable choice for China to change its development model and improve its international competitiveness. Technological progress is the first driving force to promote economic growth. However, the influence degree and mechanism of technological progress on the development of low-carbon economy are still unclear. Based on this, the paper proposes the concept of low-carbon GDP, which is used to measure the low-carbon economic development of 30 Chinese provinces. Then, the panel fixed effect model is used to study the effect degree and mechanism of technological progress on low-carbon GDP and the moderating effect of other factors on the relationship between them. The results show that, first, economically developed provinces and regions have higher per capita low-carbon GDP and low-carbon GDP index, but the speed and quality of low-carbon economic development are not necessarily higher. Second, technological progress can promote the growth of low-carbon GDP and make greater contributions to resources-poor regions. Third, improving local education can make technological progress more effective in low-carbon economic development. China needs to upgrade technological development by developing new and high-tech technologies, promoting new urbanization and strengthening education in order to promote low-carbon economic development.


Asunto(s)
Carbono , Desarrollo Económico , China , Calentamiento Global , Desarrollo Sostenible
3.
Front Vet Sci ; 11: 1356819, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500605

RESUMEN

Pseudorabies virus (PRV) can cause fatal encephalitis in newborn pigs and escape the immune system. While there is currently no effective treatment for PRV, Scutellaria baicalensis Georgi polysaccharides (SGP) and Rodgersia sambucifolia Hemsl flavonoids (RHF) are traditional Chinese herbal medicines with potential preventive and therapeutic effects against PRV infection. In order to explore which one is more effective in the prevention and treatment of PRV infection in piglets. We investigate the therapeutic effects of RHF and SGP in PRV-infected piglets using clinical symptom and pathological injury scoring systems. The immune regulatory effects of RHF and SGP on T lymphocyte transformation rate, cytokines, T cells, and Toll-like receptors were also measured to examine the molecular mechanisms of these effects. The results showed that SGP significantly reduced clinical symptoms and pathological damage in the lungs, liver, spleen, and kidneys in PRV-infected piglets and the T lymphocyte conversion rate in the SGP group was significantly higher than that in the other treatment groups, this potential dose-dependent effect of SGP on T lymphocyte conversation. Serum immunoglobulin and cytokine levels in the SGP group fluctuated during the treatment period, with SGP treatment showing better therapeutic and immunomodulatory effects in PRV-infected piglets than RHF or the combined SGP + RHF treatment. In conclusion, RHF and SGP treatments alleviate the clinical symptoms of PRV infection in piglets, and the immunomodulatory effect of SGP treatment was better than that of the RHF and a combination of both treatments. This study provides evidence for SGP in controlling PRV infection in piglets.

4.
Environ Sci Pollut Res Int ; 31(8): 11912-11932, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38225502

RESUMEN

Based on the theory of new economic geography, this paper used panel data from 284 cities in China from 2006 to 2019 to determine the effects of spatial spillover and heterogeneity of manufacturing agglomeration (MA) on urban total factor carbon productivity (TFCP) and the regulatory effect of fiscal decentralization on the outcome. The results showed that (1) MA shifted from the eastern region of China to the central and western regions, with the center of gravity moving towards the south. The spatial pattern of urban TFCP displayed the solidifying characteristics of "low-level agglomeration and high-level dispersion," with technological progress being the primary driver. (2) The MA had a significant U-shaped effect on the TFCP of local and nearby cities, promoting the improvement of urban TFCP through Jacobs' and Porter's externalities but not MAR externalities. (3) Regarding regional differences, MA had a significant U-shaped impact on urban TFCP in the eastern and central regions. At different levels of manufacturing development, there was an inverted U-shaped relationship in both manufacturing and non-manufacturing metropolitan areas. For varying degrees of manufacturing industry agglomeration, increasing the level of MA improved urban TFCP in low agglomeration areas, but inhibited it in high agglomeration areas. (4) The implementation of fiscal decentralization nationwide and in the eastern and central regions significantly weakened the impact of MA on TFCP. Furthermore, fiscal decentralization significantly enhanced the influence of MA on TFCP in cities exhibiting high levels of economic development, advanced industrial structure and strict environmental regulations. Therefore, based on the unique developmental characteristics of the manufacturing industry in various cities, fiscal policies ought to be tailored to local circumstances to support key areas. This strategy should facilitate the high-quality development of manufacturing industry and low-carbon development of cities.


Asunto(s)
Comercio , Industrias , Carbono , China , Ciudades , Desarrollo Económico , Política
5.
ACS Appl Mater Interfaces ; 16(1): 520-529, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38150322

RESUMEN

Pt-based catalysts are regarded as state-of-the-art electrocatalysts for producing clean hydrogen energy; however, their wide application is restricted by their low abundance, high cost, and poor stability. Herein, we report an integrated PtxCoy-hierarchical carbon matrix electrocatalyst (Pt/Co@NCNTs, Pt3Co@NCNTs, PtCo@NCNTs, and PtCo3@NCNTs) that is developed using a thermally driven Co migration strategy forming alloy nanoparticles to achieve efficient hydrogen evolution reaction (HER). Benefiting from its electronic regulation effect and unique hierarchical hollow structure, the Pt3Co@NCNTs catalyst loaded with 11.5 wt % Pt exhibits superior catalytic performance and durability for HER compared with commercial 20 wt % Pt/C. Under both alkaline and acidic conditions, Pt3Co@NCNTs exhibits excellent HER activity with overpotentials of 21 and 45 mV at 10 mA cm-2, respectively. Density functional theory (DFT) results further verify that the interaction between Pt and Co in Pt3Co@NCNTs can modulate electronic rearrangement, optimize the d-band center, and accelerate water dissociation and *H desorption, thereby enhancing HER activity.

6.
Electrophoresis ; 43(21-22): 2062-2073, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35621205

RESUMEN

The effects of fluid slippage on the pressure-driven electrokinetic energy conversion in conical nanochannels are systematically investigated in this paper. We present a multiphysical model that couples the Planck-Nernst-Poisson equations and the Navier-Stokes equation with a Navier slip condition to fulfill this purpose. We systematically look into the variation of various performance indicators of electrokinetic energy conversion, for example, streaming current, streaming potential, generation power, energy conversion efficiency, regulation parameter, and enchantment ratio, with the conicity of nanochannels and the slip length for two pressure differences of the same magnitude but opposite directions. Particularly, enhancement ratios related to streaming current, streaming potential, generation power, and energy conversion efficiency are defined to comprehensively measure the enhancement of the performance of electrokinetic energy conversion due to the slip length. The results demonstrate that a combination of large slip length and small conicity enhances the electrokinetic energy conversion performance significantly. Furthermore, the fluid slippage-induced enhancement of the electrokinetic energy conversion in the backward pressure difference mode is stronger than that in the forward pressure difference mode. Our results provide design and operation guidelines for pressure-driven electrokinetic energy conversion devices.

7.
Comput Struct Biotechnol J ; 20: 1541-1553, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35465162

RESUMEN

The presence of microbial communities in the reproductive tract has been revealed, and this resident microbiota is involved in the maintenance of health. Intentional modulation via probiotics has been proposed as a possible strategy to enhance reproductive health and reduce the risk of diseases. The male seminal microbiota has been suggested as an important factor that influences a couple's health, pregnancy outcomes, and offspring health. Probiotics have been reported to play a role in male fertility and to affect the health of mothers and offspring. While the female reproductive microbiota is more complicated and has been identified in both the upper and lower reproductive systems, they together contribute to health maintenance. Probiotics have shown regulatory effects on the female reproductive tract, thereby contributing to homeostasis of the tract and influencing the health of offspring. Further, through transmission of bacteria or through other indirect mechanisms, the parent's reproductive microbiota and probiotic intervention influence infant gut colonization and immunity development, with potential health consequences. In vitro and in vivo studies have explored the mechanisms underlying the benefits of probiotic administration and intervention, and an array of positive results, such as modulation of microbiota composition, regulation of metabolism, promotion of the epithelial barrier, and improvement of immune function, have been observed. Herein, we review the state of the art in reproductive system microbiota and its role in health and reproduction, as well as the beneficial effects of probiotics on reproductive health and their contributions to the prevention of associated diseases.

8.
Environ Sci Pollut Res Int ; 29(43): 65826-65841, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35488157

RESUMEN

The article uses hand-collected data regarding environmental information disclosure for Chinese 30 listed banks from 2009 to 2019 to investigate the effect of environmental information disclosure on banks' financial performance. Results show that the improvement in the quality of environmental information disclosure enhances the financial performance of banks, and this effect is intertemporal. In terms of the bank heterogeneity, national banks have a more significant effect of environmental information disclosure on their financial performance compared to regional banks. Furthermore, we provide evidence that the regional green development environment moderates the relationship between environmental information disclosure and banks' financial performance. The findings of our study add impetus for commercial banks to improve their environmental information disclosure.


Asunto(s)
Comercio , Revelación , Ambiente , Cuenta Bancaria , China , Desarrollo Económico
9.
Water Res ; 200: 117258, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34058482

RESUMEN

Sequential extraction and in-situ diffusive gradients in thin films (DGT) techniques were used to determine phosphorus (P) fractions and high-resolution 2D fluxes of labile PDGT, Fe2+DGT, and S2-DGT in sediment systems. The diffusion fluxes were subsequently calculated for different scenarios. Dynamic diffusion parameters between solid sediment and solution were also fitted using the DIFS (DGT-induced fluxes in sediments) model. The results suggested that Fe-bound P (Fe-P) was the dominant pool which contributed to the resupply potential of P in the water-sediment continuum. Significant upward decreases of labile PDGT, Fe2+DGT, and S2-DGT fluxes were detected in pristine and incubated microcosms. This dominance indicated the more obvious immobilization of labile P via oxidation of both Fe2+ and S2- in oxidic conditions. Additionally, these labile analytes in the microcosms obviously decreased after a 30-day incubation period, indicating that water-level fluctuations can significantly regulate adsorption-desorption processes of the P bound to Fe-containing minerals within a short time. Higher concentrations of labile PDGT, Fe2+DGT, and S2-DGT were measured at the shallow lake region where more drastic water-level variation occurred. This demonstrates that frequent adsorption-desorption of phosphate from the sediment particles to the aqueous solution can result in looser binding on the solid sediment surface and easier desorption in aerobic conditions via the regulation of water levels. Higher R values fitted with DIFS model suggested that more significant desorption and replenishment effect of labile P to the aqueous solution would occur in lake regions with more dramatic water-level variations. Finally, a significant positive correlation between S2-DGT and Fe2+DGT in the sediment indicated that the S2- oxidization under the conditions of low water-level can trigger the reduction of Fe(III) and subsequent release of active P. In general, speaking, frequent water-level fluctuations in the lake over time facilitated the formation and retention of the Fe(II) phase in the sediment, and desorption of Fe coupled P into the aqueous solution when the water level was high.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Difusión , Monitoreo del Ambiente , Compuestos Férricos , Sedimentos Geológicos , Cinética , Lagos , Fósforo/análisis , Agua , Contaminantes Químicos del Agua/análisis
10.
Front Psychol ; 12: 747961, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35002845

RESUMEN

This study investigated the effect of metacognitive regulation (McR) intervention on attention-deficit-hyperactivity disorder (ADHD) students' astronomy knowledge acquisition and learning motivation. Through a cognitive-behavioural treatment design, this study selected 97 ADHD learners who had poor academic performance. This study divided ADHD students randomly into one experimental group and one control group. After 15 weeks of intervention, results showed that the experimental group students performed significantly better than the control group in scientific abilities, learning motivation, and metacognition. Results suggested that the McR intervention is an effective approach for improving the ADHD students' science knowledge learning abilities.

11.
Chemphyschem ; 20(22): 2936-2945, 2019 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-31264336

RESUMEN

Electrochemical water splitting by renewable energy resources is an efficient and green approach for hydrogen gas production. However, the anodic oxygen evolution reaction (OER) largely impedes the industrial application due to its sluggish four-electron-transition kinetics. Although various materials have been developed to accelerate the OER rate, still some issues should be addressed to meet the industrial demand: (i) considerable 200-300 mV overpotential as extra onset energy input, (ii) limited survival and performance in acidic electrolyte for the majority of oxide/hydroxide composite materials, (iii) unsatisfying long-term durability and (iv) the need for facile and scalable preparation methods. Here, we emphasize on multi-metallic composites with enhanced OER activity based on both precious and nonprecious elements that outperform the unary and binary composites. The regulation effect from multi-metal incorporation is also summarized systematically: (i) introducing foreign metal atoms to the host material boosts the physical properties such as conductivity, surface area, defect density, morphology, wettability, etc., (ii) metal doping can synergistically regulate the electronic features of the host material, e. g. oxygen vacancy, eg orbit filling, coordinative number and covalence state, which can optimize the absorption/desorption energy of the M-O intermediate, (iii) chaotic impact from the added atoms twists the catalyst lattice into a more aggressive and higher energy state, which is more feasible to transform to an active intermediate with lower required energy supply. This review aims to provide a practical approach to further improve the OER performance via multi-metallic-based catalysts.

12.
J Food Biochem ; 43(7): e12880, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31353696

RESUMEN

Despite the remarkable bioactivity, the potential of EGCG3''Me to be fully utilized has not yet been completely elucidated due to its low absorption. It has been reported that phospholipids can act as agents to improve the absorption of antioxidants. Therefore, EGCG3''Me phospholipid complex (EPC) was utilized in this study to investigate its activity on gut flora of an obesity mouse model. After the administration of the complex for 8 weeks, the relative abundance of Bacteroidetes was significantly increased (p < 0.05); meanwhile, the relative abundance of Firmicutes was decreased, suggesting the potential anti-obesity effect of the complex. Furthermore, the expression of Muc2 and Reg3g were directly upregulated by EPC intervention. PRACTICAL APPLICATIONS: Although EGCG3''Me has shown excellent biological benefits, the presence of multiple hydroxyl groups and high polar properties hindered its application. This study indicated the potential of phospholipids in promoting the bioavailability of EGCG3''Me and might contribute to the production of functional food with better tea catechins absorption.


Asunto(s)
Ácido Gálico/análogos & derivados , Obesidad/tratamiento farmacológico , Obesidad/microbiología , Fosfolípidos/metabolismo , Extractos Vegetales/administración & dosificación , Animales , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/aislamiento & purificación , Camellia sinensis/química , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Ácido Gálico/administración & dosificación , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/metabolismo
13.
Zhongguo Zhong Yao Za Zhi ; 44(1): 34-39, 2019 Jan.
Artículo en Chino | MEDLINE | ID: mdl-30868809

RESUMEN

As a large micro-ecosystem in the human body,the intestinal microbiota is closely associated with the occurrence of many diseases.The clinical investigations and animal experiments have showed that traditional Chinese medicine(TCM) could maintain the balance of the intestinal micro-ecological system.This review summarized the research methods and literatures on the regulation effects of TCM,including different effective ingredients,extracts and Chinese herbal formulae,on intestinal microflora in recent five years,in order to provide a reference for the further research and development of TCM.


Asunto(s)
Microbioma Gastrointestinal/efectos de los fármacos , Medicina Tradicional China , Animales , Humanos , Intestinos/microbiología , Investigación/tendencias
14.
Environ Sci Pollut Res Int ; 25(27): 27321-27333, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30032373

RESUMEN

System fluctuations of eco-industrial symbiosis network (EISN) organization due to disturbance are very similar to the controller adjustment in the automatic control theory. Thus, a methodology is proposed in this study to assess the vulnerability of EISN based on the automatic control theory. The results show that the regulator plays a key role to enhance the resilience of the network system to vulnerability. Therefore, it is imperative to strengthen the real-time regulation and control of EISN so that the system stability is improved. In order to further explore the impact of various regulations on the system vulnerability, the influence of system stability is simulated by means of proportional, differential, and integral control. A case study with Guigang eco-industrial park (EIP) was undertaken to test this model. The results showed that when the system was disturbed at different positions, the key nodes which had great influence on system vulnerability could be selected according to the magnitude of simulation curve. By changing the ratio coefficient of proportional, differential, and integral units to adjust the ecological chain network, the system's resilience to vulnerability can be enhanced. Firstly, if basic conditions of EISN organization remain unchanged, the integral control of the policy support and infrastructure sharing should be strengthened. Secondly, the differential regulation should be improved continuously for the technological innovation capability of key node enterprises. Finally, the key chain filling projects should be introduced for proportional control so that the chain network design can be optimized from the source.


Asunto(s)
Ecología , Industrias , Modelos Teóricos , Teoría de Sistemas
15.
Bioorg Med Chem Lett ; 27(8): 1831-1834, 2017 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28284807

RESUMEN

A novel melanin with low molecular weight (LIM205, 522Da) was isolated from the fermentation broth of Lachnum sp. and its carboxymethyl derivative (CLIM205) was prepared. The immunoregulatory effects of LIM205 and CLIM205 in immuno-compromised mice induced by cyclophosphamide were investigated. The results demonstrated that both LIM205 and CLIM205 could significantly increase the thymus and spleen indices, specific and nonspecific (including carbon clearance ability) immunity, humoral and cellular immunity of mice. Treatment with LIM205 and CLIM205 could increase activities of SOD, GSH-PX, CAT and decrease content of MDA in the mice. Furthermore, for all animal tests, the immunoregulatory activities of CLIM205 were more prominent than that of LIM205. In conclusion, our findings suggested that the natural products LIM205, as well as its carboxymethyl derivative CLIM205, had significant immunoregulatory activities, which might be a promising source of immunoregulator in healthcare field.


Asunto(s)
Ascomicetos/química , Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Melaninas/química , Melaninas/farmacología , Animales , Inmunidad Celular/efectos de los fármacos , Inmunidad Humoral/efectos de los fármacos , Factores Inmunológicos/aislamiento & purificación , Melaninas/aislamiento & purificación , Ratones , Bazo/efectos de los fármacos , Bazo/inmunología , Timo/efectos de los fármacos , Timo/inmunología
16.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 30(10): 1295-1300, 2016 Oct 08.
Artículo en Chino | MEDLINE | ID: mdl-29786213

RESUMEN

OBJECTIVE: To summarize the research progress of the regulation effect of hypoxia inducible factor (HIF) on intervertebral disc. METHODS: The domestic and foreign related literature about the regulation effect of HIF on intervertebral disc was reviewed, summarized, and analyzed. RESULTS: HIF is a key transcription factor that is in response to hypoxia by cells, which is widely distributed in tissues and organs, including intervertebral disc. Hypoxia inducible factor is expressed highest in the nucleus pulposus which has the lowest oxygen concentration in the intervertebral disc. The effects of HIF include the regulation of nucleus pulposus differentiation and development, maintenance of the survival, energy metabolism, and anabolism of nucleus pulposus cells, and maintenance of the stability of extracellular matrix. CONCLUSIONS: HIF plays a vital role in the development and differentiation of intervertebral disc and maintenance of physiological function, which may become a target for the research of the mechanism and the treatment of intervertebral disc degeneration.

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