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1.
J Environ Manage ; 365: 121577, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943748

RESUMEN

This study explores the comprehensive effects of green finance (GF) on the low-carbon transition of the energy system (LTES) by analyzing panel data from 281 cities in China from 2006 to 2021. It is found that GF significantly reduces overall energy consumption and exhibits a U-shaped association with energy efficiency, while its relationship with the energy consumption structure is inverted U-shaped. After accounting for endogeneity in the robustness tests, these findings remain consistent and are therefore deemed reliable. A mechanistic analysis reveals that GF promotes industrial upgrading, technological progress, and economic agglomeration, collectively facilitating the LTES. The impact of GF on LTES shows considerable variation among regions, influenced by their levels of economic growth, extents of marketization, and governmental environmental preferences. Our findings provide new evidence for the relationship between GF and LTES, offering a scientific basis for formulating GF policies to accelerate this transformation.

2.
Molecules ; 29(12)2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38930870

RESUMEN

Conjugated polymers have attracted significant attention in the field of photocatalysis due to their exceptional properties, including versatile optimization, cost-effectiveness, and structure stability. Herein, two conjugated porous polymers, PhIN-CPP and ThIN-CPP, based on triazines, were meticulously designed and successfully synthesized using benzene and thiophene as building blocks. Based on UV diffuse reflection spectra, the photonic band gaps of PhIN-CPP and ThIN-CPP were calculated as 2.05 eV and 1.79 eV. The PhIN-CPP exhibited a high hydrogen evolution rate (HER) of 5359.92 µmol·g-1·h-1, which is 10 times higher than that of Thin-CPP (538.49 µmol·g-1·h-1). The remarkable disparity in the photocatalytic performance can be primarily ascribed to alterations in the band structure of the polymers, which includes its more stable benzene units, fluffier structure, larger specific surface area, most pronounced absorption occurring in the visible region and highly extended conjugation with a high density of electrons. The ΔEST values for PhIN-CPP and ThIN-CPP were calculated as 0.79 eV and 0.80 eV, respectively, based on DFT and TD-DFT calculations, which revealed that the incorporation of triazine units in the as-prepared CMPs could enhance the charge transfer via S1 ↔ T1 and was beneficial to the photocatalytic decomposition of H2O. This study presents a novel concept for developing a hybrid system for preparation of H2 by photocatalysis with effectiveness, sustainability, and economy.

3.
BMC Med Educ ; 23(1): 322, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37158869

RESUMEN

BACKGROUND: Paediatric orthopaedics is a significant and difficult for undergraduate students to master. During the COVID-19 pandemic, we used the WeChat platform to combine the advantages offered by problem-based learning (PBL), case-based learning (CBL) and paper review teaching methods to establish a new blended online teaching model and demonstrated its feasibility and effectiveness. OBJECTIVE: This study aims to demonstrate the feasibility and effectiveness of a new blended pedagogical method that uses the WeChat platform and combines PBL, CBL and paper review. METHODS: We enrolled 22 students participating in the Department of Paediatric Orthopaedics. They participated in the WeChat blended pedagogy mode. Their departmental rotation examination scores were compared with those of 23 students who participated in the traditional teaching method. Moreover, an anonymous questionnaire was used to evaluate students' perceptions and experiences. RESULTS: The total average scores of students who participated in the WeChat blended pedagogy mode and the traditional teaching method were 47.27 and 44.52, respectively. There were no statistically significant differences between the online teaching mode and the traditional teaching method in terms of possessing professional accomplishment, gaining knowledge and promoting interpersonal skills (P = 0.07, P = 0.12 and P = 0.65, respectively). In terms of independent clinical thinking, self-improving capability and improving clinical skills, the scores associated with the WeChat blended pedagogy mode were 8.00, 8.00 and 6.00, whereas those associated with the traditional teaching method were 6.70, 6.87 and 7.48. The overall satisfaction with the WeChat blended pedagogy mode reached 100%. A total of 64%, 86%, 68%, 64% and 59% of students chose very large or large in response to the items concerning professional accomplishment, knowledge absorption, independent clinical thinking skills, English reading and literature exploring capacity, as well as interpersonal skills, respectively. Fifteen participants claimed that the WeChat blended pedagogy mode was less helpful to them with regard to promoting the improvement of their clinical skills. Nine students claimed that the WeChat blended pedagogy mode was time-consuming. CONCLUSIONS: Our study verified the feasibility and effectiveness of the WeChat blended pedagogy mode for undergraduate paediatric orthopaedics internships. TRIAL REGISTRATION: Retrospectively registered.


Asunto(s)
COVID-19 , Internado y Residencia , Ortopedia , Niño , Humanos , Aprendizaje Basado en Problemas , Estudios de Factibilidad , Pandemias , COVID-19/epidemiología , Estudiantes
4.
J Environ Manage ; 296: 113159, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34237675

RESUMEN

To direct financial resources to cleaner production enterprises and achieve the goal of environmental governance, the Chinese government has devoted increasing efforts to facilitating green finance. As one of the major policies of green finance, the Green Credit Policy (GCP) was issued in 2012. Evaluating whether the GCP can promote green development has important significance, but few studies have explored its policy effects for the investment and financing behavior of "two high" (high energy consumption and high pollution) enterprises and environmental quality from both micro and macro perspectives. Taking the promulgation of the GCP as a quasi-natural experiment, based on a panel dataset involving 945 A-share listed companies and 30 provinces for the period of 2004-2017, this paper adopts the difference-in-difference model to explore the investment and financing behavior changes of enterprises and environmental impacts of the GCP. The following conclusions are derived. (1) The GCP provides incentives for the short-term financing behavior of "two high" enterprises, but it has a punitive effect in the long term and significantly inhibits the investment behavior of such enterprises. (2) The GCP contributes to the mitigation of sulfur dioxide and wastewater emissions. (3) The GCP has a greater effect on investment and financing behavior among state-owned and large-scale "two high" enterprises than among medium-sized and micro enterprises. (4) There exists regional heterogeneity in the effects of the GCP on the investment and financing of "two high" enterprises and environmental quality. The GCP has positive impacts in the eastern and western regions, and the policy effect is not obvious in the central region.


Asunto(s)
Conservación de los Recursos Naturales , Desarrollo Sostenible , China , Política Ambiental , Políticas
5.
Environ Geochem Health ; 42(2): 625-646, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31428947

RESUMEN

Health is considered the most important factor for individual well-being and a country's sustainable development. Among the influential factors of population health, sanitary infrastructure, particularly sanitary toilets and innocuous-sanitary toilets, have already attracted attention. In recent years, to improve the overall health status of rural residents, the Chinese government has promoted the "toilet revolution" in rural areas to update and modernize the facilities of toilets. Given that migrant workers contribute significantly to China's economic growth, and that the migrant workers generally lived in rural areas before they moved to urban areas to find jobs, it is of great interest and importance to investigate the impacts of sanitary infrastructure in rural areas on the migrant workers. This study analyzes the spatial characteristic of rural sanitation facilities' implementation and looks for possible correlation between the health status of migrant workers and the implementation of sanitation facilities in their hometowns. Micro-survey data of migrant workers' health status from China Household Income Projects (CHIP) 2013 and macro-data of provincial economic factors are matched to provide a quality analysis. The analysis of the spatial distribution shows that there were significantly large gaps between the prevalence rates of sanitary toilets in provinces. Furthermore, the regression analysis indicates that the implementation of sanitary toilets and innocuous-sanitary toilets exhibits a positive effect on the overall health status of migrant workers, although the effects of the innocuous-sanitary toilets are greater. Moreover, the positive influences of both types of toilets on population health are higher in the provinces with relatively greater annual precipitation and higher average temperature.


Asunto(s)
Aparatos Sanitarios/estadística & datos numéricos , Saneamiento/estadística & datos numéricos , Migrantes , China , Femenino , Humanos , Masculino , Salud Rural , Población Rural , Factores Socioeconómicos , Encuestas y Cuestionarios
6.
BMC Genomics ; 15: 41, 2014 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-24438544

RESUMEN

BACKGROUND: Genomic structure variation (GSV) is widely distributed in various organisms and is an important contributor to human diversity and disease susceptibility. Efficient approaches to induce targeted genomic structure variation are crucial for both analytic and therapeutic studies of GSV. Here, we presented an efficient strategy to induce targeted GSV including chromosomal deletions, duplications and inversions in a precise manner. RESULTS: Utilizing Transcription Activator-Like Effector Nucleases (TALEN) designed to target two distinct sites, we demonstrated targeted deletions, duplications and inversions of an 8.9 Mb chromosomal segment, which is about one third of the entire chromosome. We developed a novel method by combining TALEN-induced GSV and single stranded oligodeoxynucleotide (ssODN) mediated gene modifications to reduce unwanted mutations occurring during the targeted GSV using TALEN or Zinc finger nuclease (ZFN). Furthermore, we showed that co-introduction of TALEN and ssODN generated unwanted complex structure variation other than the expected chromosomal deletion. CONCLUSIONS: We demonstrated the ability of TALEN to induce targeted GSV and provided an efficient strategy to perform GSV precisely. Furthermore, it is the first time to show that co-introduction of TALEN and ssODN generated unwanted complex structure variation. It is plausible to believe that the strategies developed in this study can be applied to other organisms, and will help understand the biological roles of GSV and therapeutic applications of TALEN and ssODN.


Asunto(s)
Endonucleasas/genética , Variación Estructural del Genoma , Algoritmos , Animales , Secuencia de Bases , Bombyx/genética , Deleción Cromosómica , Duplicación Cromosómica , Inversión Cromosómica , Cromosomas/genética , Cromosomas/metabolismo , Endonucleasas/metabolismo , Genoma , Oligodesoxirribonucleótidos/síntesis química , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/metabolismo , ARN Mensajero/metabolismo , Análisis de Secuencia de ADN
7.
Front Microbiol ; 15: 1325466, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38384268

RESUMEN

Objective: Investigating the causal relationship between Lachnospiraceae and Appendicular lean mass (ALM) and identifying and quantifying the role of Aminopeptidase O Protein (AOPEP) as a potential mediator. Methods: The summary statistics data of gut microbiota composition from the largest available genome-wide association study (GWAS) meta-analysis conducted by the MiBioGen Consortium (n = 13,266). Appendicular lean mass data were obtained from the UK-Biobank (n = 450,243). We conducted bidirectional two-sample Mendelian randomization (MR) analysis using summary-level data from GWAS to investigate the causal relationship between Lachnospiraceae and ALM. Additionally, we employed a drug-targeted MR approach to assess the causal relationship between AOPEP and ALM. Finally, a two-step MR was employed to quantitatively estimate the proportion of the effect of Lachnospiraceae on ALM that is mediated by AOPEP. Cochran's Q statistic was used to quantify heterogeneity among instrumental variable estimates. Results: In the MR analysis, it was found that an increase in genetically predicted Lachnospiraceae [OR = 1.031, 95% CI (1.011-1.051), P = 0.002] is associated with an increase in ALM. There is no strong evidence to suggest that genetically predicted ALM has an impact on Lachnospiraceae genus [OR = 1.437, 95% CI (0.785-2.269), P = 0.239]. The proportion of genetically predicted Lachnospiraceae mediated by AOPEP was 34.2% [95% CI (1.3%-67.1%)]. Conclusion: Our research reveals that increasing Lachnospiraceae abundance in the gut can directly enhance limb muscle mass and concurrently suppress AOPEP, consequently mitigating limb muscle loss. This supports the potential therapeutic modulation of gut microbiota for sarcopenia. Interventions such as drug treatments or microbiota transplantation, aimed at elevating Lachnospiraceae abundance and AOPEP inhibition, synergistically improve sarcopenia in the elderly, thereby enhancing the overall quality of life for older individuals.

8.
J Colloid Interface Sci ; 637: 41-54, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36682117

RESUMEN

Conjugated porous polymers (CPPs) have been widely reported as promising photocatalysts. However, the realization of powerful photocatalytic hydrogen production performance still benefits from the rational design of molecular frameworks and the appropriate choice of building monomers. Herein, we synthesized two novel conjugated porous polymers (CPPs) by copolymerizing pyrene and 1,3,5-triazine building blocks. It is found that minor structural changes in the peripheral groups of the triazine units can greatly affect the photocatalytic activity of the polymers. Compared with the phenyl-linkage unit, the thiophene-linkage unit can give CPP a wider absorption range of visible light, a narrower band gap, a higher transmission and separation efficiency of photo-generated carriers (electrons/holes), and a better interface contact with the photocatalytic reaction solution. The catalyst containing thiophene-triazine (ThPy-CPP) has an efficient photocatalytic hydrogen evolution rate of 21.65 and 16.69 mmol g-1h-1 under full-arc spectrum and visible light without the addition of a Pt co-catalyst, respectively, much better than the one containing phenyl-triazine (PhPy-CPP, only 5.73 and 3.48 mmol g-1h-1). This study provides a promising direction to design and construct highly efficient, cost-effective CPP-based photocatalysts, for exploring the application of noble metal-free catalysts in photocatalytic hydrogen evolution.

9.
Chem Asian J ; 17(21): e202200806, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36000512

RESUMEN

A reliable and efficient palladium-catalyzed cascade cyclization/alkylation of oxime ethers with unactivated alkenes is described, affording a whole variety of structurally diverse isoxazole derivatives in moderate to good yields with excellent functional group compatibility. Ionic liquid [Aeim]Br not only acts as an environmentally friendly solvent but also acts as an accelerating agent to provide excess bromine source to eliminate bromomethane from oxime ethers. More importantly, the use of "chain-walking" strategy provides a novel methodology in organic synthesis to rapid generation of molecular complexity from readily available starting materials.


Asunto(s)
Éteres , Paladio , Ciclización , Oximas , Catálisis , Estructura Molecular , Alquilación , Alquenos
10.
RSC Adv ; 10(55): 33155-33160, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-35515034

RESUMEN

An efficient electrochemical transformation of a variety of alkenes and sulfonyl hydrazides into vinyl sulfones with a catalytic amount of tetrabutylammonium iodide in water is reported. The reaction proceeds smoothly to afford vinyl sulfones with good selectivities and yields at room temperature under air in an undivided cell. Cyclic voltammograms and control experiments have been performed to provide preliminary insight into the reaction mechanism. The key features of this reaction include using pure water as solvent, transition metal- and oxidant-free conditions, and being easily scaled up to gram-scale synthesis.

11.
Molecules ; 14(4): 1546-60, 2009 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-19384284

RESUMEN

Six 3-methylpyridine zwitterions and six quinoline zwitterions were synthesized through the reaction of 4-hydroxycoumarins, p-benzoquinone and the corresponding N-aromatics. The novel pseudo-cyclic face-to-face rigid structure of the zwitterion was elucidated by (1)H-NMR at different temperatures, and assumed to be caused by both the intramolecular ion pair attraction and the steric interaction.


Asunto(s)
4-Hidroxicumarinas , Iones , 4-Hidroxicumarinas/síntesis química , 4-Hidroxicumarinas/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Piridinas/química , Quinolinas/química
12.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 30(1): 60-3, 2005 Feb.
Artículo en Zh | MEDLINE | ID: mdl-15871190

RESUMEN

OBJECTIVE: To investigate the application of pulsed-wave Doppler tissue imaging ( PW-DTI) in evaluating left ventricular systolic and diastolic function in patients with chronic heart failure (CHF). METHODS: Mitral annular velocities (MAV) were measured by PW-DTI in 35 patients with CHF and 25 healthy subjects. Traditional indices for evaluating the global left ventricular function by conventional echocardiography were also studied as a comparison. RESULTS: Peak systolic, peak early diastolic, peak late diastolic mitral annular velocities ( Sa, Ea, Aa), and Ea/Aa ratio progressively decreased in CHF patients compared with the healthy subjects (P <0.01 ). Sa of the mitral annulus correlated linearly with the left ventricle ejection fraction (LVEF) (r =0.890, P < 0.01). Compared with the healthy subjects, Ea in all 3 subgroups of diastolic dysfunction in the CHF group significantly decreased (P <0.01). Aa in 2 subgroups (pseudonormal filling and restrictive filling) decreased (P < 0.01 ) and the decreased Ea/Aa was found in the delayed relaxation and pseudonormal filling subgroups compared with the healthy subjects (P<0.001). CONCLUSION: MAV measured by PW-DTI can be used for assessing the left ventricular systolic and diastolic function in CHF patients.


Asunto(s)
Ecocardiografía Doppler de Pulso , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/fisiopatología , Función Ventricular Izquierda/fisiología , Diástole , Femenino , Humanos , Masculino , Sístole
13.
Org Lett ; 6(26): 4853-5, 2004 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-15606083

RESUMEN

[reaction: see text] A unique reaction of 4-hydroxycoumarins with p-benzoquinone and pyridine was found, and through the reaction, six zwitterionic 4-hydroxycoumarin derivatives were synthesized. The structures of these compounds were determined by IR, MS(ESI), 1H NMR, 13C NMR, and single-crystal X-ray diffraction studies.


Asunto(s)
4-Hidroxicumarinas/química , 4-Hidroxicumarinas/síntesis química , Benzoquinonas/química , Piridinas/química , Espectroscopía de Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/normas , Modelos Moleculares , Estructura Molecular , Estándares de Referencia , Sensibilidad y Especificidad , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrofotometría Infrarroja/métodos , Estereoisomerismo , Difracción de Rayos X
14.
PLoS One ; 7(9): e45035, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23028749

RESUMEN

Establishment of efficient genome editing tools is essential for fundamental research, genetic engineering, and gene therapy. Successful construction and application of transcription activator-like effector nucleases (TALENs) in several organisms herald an exciting new era for genome editing. We describe the production of two active TALENs and their successful application in the targeted mutagenesis of silkworm, Bombyx mori, whose genetic manipulation methods are parallel to those of Drosophila and other insects. We will also show that the simultaneous expression of two pairs of TALENs generates heritable large chromosomal deletion. Our results demonstrate that (i) TALENs can be used in silkworm and (ii) heritable large chromosomal deletions can be induced by two pairs of TALENs in whole organisms. The generation and the high frequency of TALENs-induced targeted mutagenesis in silkworm will promote the genetic modification of silkworm and other insect species.


Asunto(s)
Bombyx/enzimología , Bombyx/genética , Endonucleasas/metabolismo , Técnicas Genéticas , Genoma de los Insectos/genética , Transactivadores/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Deleción Cromosómica , Femenino , Vectores Genéticos/genética , Mutación de Línea Germinal/genética , Datos de Secuencia Molecular , Mosaicismo , Mutagénesis/genética , Fenotipo
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