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1.
Sci Rep ; 13(1): 13758, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37612378

RESUMEN

Emission Trading System (ETS) is an innovative practice under the progress of green development in China. It is also an important method for China to achieve market-oriented environmental governance in ecological civilization construction. The ETS pilot policy has implemented for more than 10 years. However, the co-benefits of ETS pilot policy by the integration of energy consumption, carbon and sulfur dioxide emissions, and wastewater has not been evaluated. In order to fill this gap, we use the 2003-2017 annual data of 30 China's provinces (municipalities and autonomous regions), and utilize the Difference-in-Differences (DID) model and Propensity Score Matching (PSM-DID) methodology to evaluate the co-benefits of ETS pilot policy on energy conservation and emission reduction. We find that the ETS pilot policy significantly promote energy conservation and emission reduction. Eastern and central China have significantly benefited from the policy, while the western China has not due to the limited technology and innovation as well as an imbalance of the industrial structure. The results provide the policy reference for China's government and institutions as well as the governments and institutions around the world to fulfill their commitments to save energy and reduce emissions, and early achieve the carbon peaking and carbon neutralization.

2.
Angew Chem Int Ed Engl ; 62(31): e202306367, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37276015

RESUMEN

Illicium sesquiterpenes are a large family of biologically active secondary metabolites isolated from Illicium species of plants and are well-known for their activity of neurite outgrowth in cultured neurons. Herein, we propose a comprehensive biosynthetic pathway for illicium sesquiterpenes and report a synthetic route to illisimonin A and merrilactone A based on it. We think that the carbon scaffolds of most of the illicium sesquiterpenes could be synthesized from a dicarbonyl derivative of allo-cedrane through retro-Dieckmann condensation, oxidative cleavage and aldol reaction at suitable oxidation states in Nature. The common intermediate for illisimonin A and merrilactone A similar to the dicarbonyl derivative of allo-cedrane was assembled with up to 82 % ee by an asymmetric intramolecular desymmetrizing reductive Heck reaction by the use of a new type of chiral phosphine ligand. The syntheses of illisimonin A and merrilactone A supported the key transformations of the proposed biosynthetic pathway.


Asunto(s)
Illicium , Sesquiterpenos , Neuronas , Lactonas , Estructura Molecular
3.
Stoch Environ Res Risk Assess ; : 1-12, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37362843

RESUMEN

The global pandemic caused by the outbreak of COVID-19 has posed significant risks to our health. Preventive measures such as closed management have greatly affected the economies, environments and societies of various countries. Economy, air pollution and income are three important interconnected aspects of sustainable development. However, current research lacks systematic quantitative analysis of their relationships. To fill the gap, this study adopts monthly data from January 2016 to April 2022 and constructs both a Simultaneous Equation Model (SEM) and a Time Varying Parameter Stochastic Volatility Vector Autoregressive (TVP-SV-VAR) model to empirically analyze the impact of COVID-19 on China's economy, air pollution and income. This study finds that the COVID-19 has a negative impact on China's economy and income, and a positive impact on air pollution, and the impact of the COVID-19 is systematic. In addition, there is an inverted-U shaped relationship between air pollution and economics, and a positive correlation between economic and income. The impact of COVID-19 on the economy, air pollution and income show a process of sharp fluctuations to gradual stabilization that gradually stabilized over time. This process is time-varying in the short-term, medium-term and long-term. The impacts are persistent at three different time points (before, during and after the outbreak of COVID-19), but the negative impact on the economy and income is persistent, while the positive impact on air pollution is limited. This study provides a more systematic and dynamic understanding of the COVID-19 preventive and mitigation measures in China and even the world, which helps to provide insights into the formulation of more comprehensive planning strategies in the future. Supplementary Information: The online version contains supplementary material available at 10.1007/s00477-023-02450-z.

4.
Sensors (Basel) ; 23(7)2023 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-37050749

RESUMEN

Soybean is one of the world's most consumed crops. As the human population continuously increases, new phenotyping technology is needed to develop new soybean varieties with high-yield, stress-tolerant, and disease-tolerant traits. Hyperspectral imaging (HSI) is one of the most used technologies for phenotyping. The current HSI techniques with indoor imaging towers and unmanned aerial vehicles (UAVs) suffer from multiple major noise sources, such as changes in ambient lighting conditions, leaf slopes, and environmental conditions. To reduce the noise, a portable single-leaf high-resolution HSI imager named LeafSpec was developed. However, the original design does not work efficiently for the size and shape of dicot leaves, such as soybean leaves. In addition, there is a potential to make the dicot leaf scanning much faster and easier by automating the manual scan effort in the original design. Therefore, a renovated design of a LeafSpec with increased efficiency and imaging quality for dicot leaves is presented in this paper. The new design collects an image of a dicot leaf within 20 s. The data quality of this new device is validated by detecting the effect of nitrogen treatment on soybean plants. The improved spatial resolution allows users to utilize the Normalized Difference Vegetative Index (NDVI) spatial distribution heatmap of the entire leaf to predict the nitrogen content of a soybean plant. This preliminary NDVI distribution analysis result shows a strong correlation (R2 = 0.871) between the image collected by the device and the nitrogen content measured by a commercial laboratory. Therefore, it is concluded that the new LeafSpec-Dicot device can provide high-quality hyperspectral leaf images with high spatial resolution, high spectral resolution, and increased throughput for more accurate phenotyping. This enables phenotyping researchers to develop novel HSI image processing algorithms to utilize both spatial and spectral information to reveal more signals in soybean leaf images.


Asunto(s)
Productos Agrícolas , Imágenes Hiperespectrales , Humanos , Fenotipo , Hojas de la Planta , Nitrógeno
5.
Sensors (Basel) ; 23(7)2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37050815

RESUMEN

Image-based spectroscopy phenotyping is a rapidly growing field that investigates how genotype, environment and management interact using remote or proximal sensing systems to capture images of a plant under multiple wavelengths of light. While remote sensing techniques have proven effective in crop phenotyping, they can be subject to various noise sources, such as varying lighting conditions and plant physiological status, including leaf orientation. Moreover, current proximal leaf-scale imaging devices require the sensors to accommodate the state of the samples during imaging which induced extra time and labor cost. Therefore, this study developed a proximal multispectral imaging device that can actively attract the leaf to the sensing area (target-to-sensor mode) for high-precision and high-throughput leaf-scale phenotyping. To increase the throughput and to optimize imaging results, this device innovatively uses active airflow to reposition and flatten the soybean leaf. This novel mechanism redefines the traditional sensor-to-target mode and has relieved the device operator from the labor of capturing and holding the leaf, resulting in a five-fold increase in imaging speed compared to conventional proximal whole leaf imaging device. Besides, this device uses artificial lights to create stable and consistent lighting conditions to further improve the quality of the images. Furthermore, the touch-based imaging device takes full advantage of proximal sensing by providing ultra-high spatial resolution and quality of each pixel by blocking the noises induced by ambient lighting variances. The images captured by this device have been tested in the field and proven effective. Specifically, it has successfully identified nitrogen deficiency treatment at an earlier stage than a typical remote sensing system. The p-value of the data collected by the device (p = 0.008) is significantly lower than that of a remote sensing system (p = 0.239).


Asunto(s)
Glycine max , Tacto , Tecnología de Sensores Remotos/métodos , Plantas , Hojas de la Planta
6.
Head Face Med ; 18(1): 40, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36476624

RESUMEN

PURPOSE: The objective of the study was to explore the effect of periodontally accelerated osteogenic orthodontics (PAOO) in orthodontic patients with bone dehiscence and fenestration in the anterior alveolar region of the mandible. METHODS: A retrospective study was performed in 42 patients with bone dehiscence and fenestrations in the anterior alveolar region of the mandible who underwent the PAOO technique. The bleeding index (BI), probing depth (PD), keratinized gingiva width (KGW), gingival recession level (GRL), and gingival phenotype were recorded and assessed at baseline and 6 and 12 months postoperatively. Cone-beam computerized tomography was used to measure bone volume in terms of root length (RL), horizontal bone thickness at different levels, and vertical bone height at baseline and 6 months and 12 months after surgery. RESULTS: The sample was composed of 42 patients (22 males and 20 females; mean age, aged 25.6 ± 4.8 years) with 81 teeth showing dehiscence/fenestrations and 36 sites presenting gingival recessions. There was no significant difference in BI, PD, or KGW (between baseline and 6 or 12 months postoperatively) based on the clinical evaluations (P > 0.05). Gingival recession sites demonstrated a significant reduction in the GRL after surgery (P < 0.05). Furthermore, the proportion of teeth with a thick gingival phenotype increased from 33.61% at baseline to 53.13% at the end of the follow-up. In addition, the bone thickness measurements at the mid-root and crestal levels were markedly increased compared with the baseline values (P < 0.05), although the increase in thickness at the apical level was not statistically significant (P > 0.05). CONCLUSIONS: Within the limitations of the study, the results show that the PAOO technique is beneficial to periodontal conditions in terms of soft and hard tissue augmentation. The PAOO procedure may represent a safe and efficient treatment for orthodontic patients with bone dehiscence and fenestration. TRIAL REGISTRATION: This study was approved by the ethics committee of the stomatological hospital affiliated with Xi'an Jiaotong University (xjkqll [2019] No. 016) and registered in the Chinese Clinical Trial Registry (ChiCTR2100053092).


Asunto(s)
Recesión Gingival , Humanos , Estudios Retrospectivos , Recesión Gingival/diagnóstico por imagen , Recesión Gingival/cirugía , Resultado del Tratamiento
7.
Nanomaterials (Basel) ; 12(11)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35683790

RESUMEN

The development of lithium-ion batteries largely relies on the cathode and anode materials. In particular, the optimization of cathode materials plays an extremely important role in improving the performance of lithium-ion batteries, such as specific capacity or cycling stability. Carbon coating modifying the surface of cathode materials is regarded as an effective strategy that meets the demand of Lithium-ion battery cathodes. This work mainly reviews the modification mechanism and method of carbon coating, and summarizes the recent progress of carbon coating on some typical cathode materials (LiFePO4, LiMn2O4, LiCoO2, NCA (LiNiCoAlO2) and NCM (LiNiMnCoO2)). In addition, the limitations of the carbon coating on the cathode are also introduced. Suggestions on improving the effectiveness of carbon coating for future study are also presented.

8.
Odontology ; 110(4): 795-804, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35290532

RESUMEN

Gingival "black triangle" is common in clinical which due to interdental papilla recession. The cause of the loss of papilla is multi-factorial and it may be caused by the absorption of interdental alveolar bone or abnormal tooth position. Besides, it is a common complication after orthodontics and implant surgery. Recession of gingival papilla influences interdental plaque control, increasing food impaction and alveolar bone absorption, causing aesthetic and pronunciation problems. Thus, the way of reducing or eliminating the gingival "black triangle" has become one of the most essential problems for dentists. Concentrated growth factor (CGF) and low-level-laser therapy have been widely used, respectively, and CGF was considered as the only self-substance which has soft tissue regeneration function. This study aims to evaluate the efficacy of regenerating interdental papilla by Liquid phase concentrated growth factor (LPCGF) injection with low-level-laser therapy (LLLT).


Asunto(s)
Encía , Rayos Láser , Péptidos y Proteínas de Señalización Intercelular , Luz
9.
Bioact Mater ; 5(1): 82-91, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31956737

RESUMEN

Tissue engineering is promising in realizing successful treatments of human body tissue loss that current methods cannot treat well or achieve satisfactory clinical outcomes. In scaffold-based bone tissue engineering, a high performance scaffold underpins the success of a bone tissue engineering strategy and a major direction in the field is to produce bone tissue engineering scaffolds with desirable shape, structural, physical, chemical and biological features for enhanced biological performance and for regenerating complex bone tissues. Three-dimensional (3D) printing can produce customized scaffolds that are highly desirable for bone tissue engineering. The enormous interest in 3D printing and 3D printed objects by the science, engineering and medical communities has led to various developments of the 3D printing technology and wide investigations of 3D printed products in many industries, including biomedical engineering, over the past decade. It is now possible to create novel bone tissue engineering scaffolds with customized shape, architecture, favorable macro-micro structure, wettability, mechanical strength and cellular responses. This article provides a concise review of recent advances in the R & D of 3D printing of bone tissue engineering scaffolds. It also presents our philosophy and research in the designing and fabrication of bone tissue engineering scaffolds through 3D printing.

10.
Org Lett ; 21(23): 9545-9549, 2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31725304

RESUMEN

Herein, we report a straightforward, environmentally friendly, and controllable palladium/ligand catalytic system to enable reductive/oxidative Heck reactions of cyclic enones with thiophene or furan derivatives via C-H activation. The key to this tunable reaction is the appropriate intercepting thienyl-Pd(II)-enolate during the enolization process. Such a controllable and economic protocol would not only provide efficient methods to construct various value-added ß-heteroarylated cyclic ketones/enones but also shed light on developing other conjugate addition reactions via C-H activation.

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