Metal–organic frameworks (MOFs) are an interesting and useful class of coordination polymers, constructed from metal ion/cluster nodes and functional organic ligands through coordination bonds, and ...have attracted extensive research interest during the past decades. Due to the unique features of diverse compositions, facile synthesis, easy surface functionalization, high surface areas, adjustable porosity, and tunable biocompatibility, MOFs have been widely used in hydrogen/methane storage, catalysis, biological imaging and sensing, drug delivery, desalination, gas separation, magnetic and electronic devices, nonlinear optics, water vapor capture, etc. Notably, with the rapid development of synthetic methods and surface functionalization strategies, smart MOF‐based nanocomposites with advanced bio‐related properties have been designed and fabricated to meet the growing demands of MOF materials for biomedical applications. This work outlines the synthesis and functionalization and the recent advances of MOFs in biomedical fields, including cargo (drugs, nucleic acids, proteins, and dyes) delivery for cancer therapy, bioimaging, antimicrobial, biosensing, and biocatalysis. The prospects and challenges in the field of MOF‐based biomedical materials are also discussed.
The synthesis and functionalization of metal–organic frameworks (MOFs) for biomedical applications in the delivery of cargos (drugs, nucleic acids, proteins, and dyes) for cancer therapy, bioimaging, antimicrobial, biosensing, and biocatalysis are overviewed, and the development prospects and challenges of MOF‐based theranostic systems are also discussed.
Factor price distortions and resource misallocation are important sources of productivity differences between regions. Promoting the free flow of factors of production is conducive to giving full ...play to the decisive role of the market in allocating resources, which is crucial to helping a country's economy develop in a high-quality and sustainable manner. This paper proposes a new approach to measuring factor market distortions and establishes the relationship between factor price distortions and a country's economic growth. This paper examines the resource misallocation and efficiency loss of 31 provinces in China from 2004 to 2020, and proposes an analytical framework for resource misallocation among regions, with which the Total Factor Productivity (TFP) and the factor price distortion of provinces in China are calculated. The calculation results indicate that the TFP of China's provinces gradually declines from the eastern coast to the western inland. The resource allocation efficiency in the eastern and central areas is higher than that in the western areas, so is the factor price, and its distortion causes nearly 6% of loss of output value in China. China's economic growth is still reliant on the increase of factor input and technological development and the improvement of resource allocation efficiency has no significant effect on growth.
Land cover (LC) determines the energy exchange, water and carbon cycle between Earth's spheres. Accurate LC information is a fundamental parameter for the environment and climate studies. Considering ...that the LC in China has been altered dramatically with the economic development in the past few decades, sequential and fine-scale LC monitoring is in urgent need. However, currently, fine-resolution annual LC dataset produced by the observational images is generally unavailable for China due to the lack of sufficient training samples and computational capabilities. To deal with this issue, we produced the first Landsat-derived annual China land cover dataset (CLCD) on the Google Earth Engine (GEE) platform, which contains 30 m annual LC and its dynamics in China from 1990 to 2019. We first collected the training samples by combining stable samples extracted from China's land-use/cover datasets (CLUDs) and visually interpreted samples from satellite time-series data, Google Earth and Google Maps. Using 335 709 Landsat images on the GEE, several temporal metrics were constructed and fed to the random forest classifier to obtain classification results. We then proposed a post-processing method incorporating spatial–temporal filtering and logical reasoning to further improve the spatial–temporal consistency of CLCD. Finally, the overall accuracy of CLCD reached 79.31 % based on 5463 visually interpreted samples. A further assessment based on 5131 third-party test samples showed that the overall accuracy of CLCD outperforms that of MCD12Q1, ESACCI_LC, FROM_GLC and GlobeLand30. Besides, we intercompared the CLCD with several Landsat-derived thematic products, which exhibited good consistencies with the Global Forest Change, the Global Surface Water, and three impervious surface products. Based on the CLCD, the trends and patterns of China's LC changes during 1985 and 2019 were revealed, such as expansion of impervious surface (+148.71 %) and water (+18.39 %), decrease in cropland (−4.85 %) and grassland (−3.29 %), and increase in forest (+4.34 %). In general, CLCD reflected the rapid urbanization and a series of ecological projects (e.g. Gain for Green) in China and revealed the anthropogenic implications on LC under the condition of climate change, signifying its potential application in the global change research. The CLCD dataset introduced in this article is freely available at https://doi.org/10.5281/zenodo.4417810 (Yang and Huang, 2021).
Previous research has investigated the influence of long-term motor training on the brain activity of motor processes, but the findings are inconsistent. To clarify how acquiring motor expertise ...induces cortical reorganization during motor task performance, the current study conducted a quantitative meta-analysis on 26 functional magnetic resonance imaging (fMRI) studies that investigate motor task performance in people with long-term motor training experience (e.g., athletes, musicians, and dancers) and control participants. Meta-analysis of the brain activation in motor experts and novices showed similar effects in the bilateral frontal and parietal regions. The meta-analysis on the contrast between motor experts and novices indicated that experts showed stronger effects in the left inferior parietal lobule (BA 40) than did novices in motor execution and prediction tasks. In motor observation tasks, experts showed stronger effects in the left inferior frontal gyrus (BA 9) and left precentral gyrus (BA 6) than novices. On the contrary, novices had stronger effects in the right motor areas and basal ganglia as compared with motor experts. These results indicate that motor experts have effect increases in brain areas involved in action planning and action comprehension, and suggest that intensive motor training might elaborate the motor representation related to the task performance.
Automatic modulation recognition (AMR) is an essential and challenging topic in the development of the cognitive radio (CR), and it is a cornerstone of CR adaptive modulation and demodulation ...capabilities to sense and learn environments and make corresponding adjustments. AMR is essentially a classification problem, and deep learning achieves outstanding performances in various classification tasks. So, this paper proposes a deep learning-based method, combined with two convolutional neural networks (CNNs) trained on different datasets, to achieve higher accuracy AMR. A CNN is trained on samples composed of in-phase and quadrature component signals, otherwise known as in-phase and quadrature samples, to distinguish modulation modes, that are relatively easy to identify. We adopt dropout instead of pooling operation to achieve higher recognition accuracy. A CNN based on constellation diagrams is also designed to recognize modulation modes that are difficult to distinguish in the former CNN, such as 16 quadratic-amplitude modulation (QAM) and 64 QAM, demonstrating the ability to classify QAM signals even in scenarios with a low signal-to-noise ratio.
Teachers' continuing professional development (CPD) is a dynamic process that coordinates teachers' external behavior and internal states. Most teachers participate in varied forms of CPD activities ...either voluntarily or contractually. The more motivated teachers are to engage in CPD, the more likely they achieve professional and personal growth. Against this backdrop, the current study, adopting the framework of self-determination theory (SDT), sought to investigate the types and levels of Chinese college TEFL (Teaching English as a Foreign Language, hereafter TEFL) teachers' motivation toward CPD. The questionnaire survey was administered to 402 academics who taught the English language in diverse universities in China. The quantitative analysis showed that teachers exhibited stronger identified regulation and intrinsic motivation than external regulation. Specifically, the exploratory factor analysis identified five motivational orientations: inner-directed academic improvement and cognitive interest, academic self-fulfillment and obligation, academic and social responsibility, social recognition and promotion, lacking the intention for CPD, which corresponded to the SDT motivation continuum. To triangulate, further interviews were conducted with 12 TEFL teachers. The findings of the qualitative analysis-the thematic analysis through Nvivo (Version 12) on the open-ended question and the interviews, revealed that teachers' struggles in CPD were mainly concerned with the school-related, CPD-related, and teacher-related problems. Moreover, a big gap between teachers' needs and contextual support was found to be bridged. Based on the findings, this study proposed that social conditions should support teachers' basic psychological needs in order to sustain and enhance TEFL teachers' motivation for CPD.
Azithromycin (AZM) has been used to treat chronic inflammatory airway diseases because it regulates cell–cell contact between airway epithelial cells. Airway mucus hypersecretion is an important ...component of chronic respiratory diseases. Mucin 5AC (MUC5AC) is the major mucin produced by airway epithelial cells, and hypersecretion of MUC5AC is a sign of various pulmonary inflammatory diseases. Recently, it was found that matrix metallopeptidase 9 is involved in mucus hypersecretion. Moreover, AZM can inhibit the ability of TNF-α-to induce interleukin (IL)-8 production. This review focuses on the effects on AZM that may be beneficial in inhibiting MUC5AC, matrix metalloprotease-9 and IL-8 production in airway epithelial cells. In addition, recent studies have begun to assess activation of mitogen-activated protein kinase (MAPK) signaling pathways in response to AZM. Understanding these new developments may be helpful for clinicians.
Enantio‐ and diastereoselective synthesis of trans‐2,3‐disubstituted indanones is achieved by intramolecular hydroacylation of 2‐alkenylbenzaldehydes bearing trisubstituted alkenyl groups under ...cobalt‐chiral diphosphine catalysis. Notably, a high level of enantioselectivity is induced regardless of the stereochemistry (E/Z ratio) of the alkenyl group of the starting material. Deuterium‐labeling experiments shed light on the productive reaction pathways of the E‐ and Z‐isomers.
EZ: Enantio‐ and diastereoselective synthesis of trans‐2,3‐disubstituted indanones is achieved by intramolecular hydroacylation of 2‐alkenylbenzaldehydes containing trisubstituted alkenyl groups under cobalt‐chiral diphosphine catalysis. High level of enantioselectivity is induced regardless of the stereochemistry (E/Z ratio) of the alkenyl group of the starting material.
PDF
