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"Liang, Li"
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Internet use and frailty in middle-aged and older adults: findings from developed and developing countries
Background
With increasing trend of internet use in all age groups, whether internet use can prevent frailty in middle-aged and older adults remains unclear.
Methods
Five cohorts, including Health and Retirement Study (HRS), China Health and Retirement Longitudinal Study (CHARLS), the Survey of Health, Ageing and Retirement in Europe (SHARE), English Longitudinal Study of Aging (ELSA), and Mexican Health and Aging Study (MHAS), were used in this study. Internet use, social isolation, and frailty status was assessed using similar questions. The Generalized estimating equations models, random effects meta-analysis, COX regression, and mediation analysis were utilized.
Results
In the multicohort study, a total of 155,695 participants were included in main analysis. The proportion of internet use was varied across countries, ranging from 5.56% in China (CHARLS) to 83.46% in Denmark (SHARE). According to the generalized estimating equations models and meta-analysis, internet use was inversely associated with frailty, with the pooled ORs (95%CIs) of 0.72 (0.67,0.79). The COX regression also showed that participants with internet use had a lower risk of frailty incidence. Additionally, the association was partially mediated by social isolation and slightly pronounced in participants aged 65 and over, male, not working for payment, not married or partnered, not smoking, drinking, and not co-residence with children.
Conclusions
Our findings highlight the important role of internet use in preventing frailty and recommend more engagements in social communication and activities to avoid social isolation among middle-aged and older adults.
Journal Article
هذه هي الصين : قوة تسير نحو العالم
يركز كتاب \"هذه هي الصين\" على سرد قصص تنمية الصين في العصر الجديد. وقد غير الدكتور تشانغ وي وي طريقته المعروفة بالتوجيه والإرشاد في البرامج الأيديولوجية والنظرية في الماضي، وعبر عنها بلغة شعبية سائغة، وحجج منطقية صارمة، وبيانات حقيقية، وتصادمات صريحة للأفكار، وتقنيات عرض مبتكرة لمساعدة الجمهور على فهم النموذج الصيني والطريق الصيني، وتعزيز ثقتهم بمستقبل الصين.
Book
Catalytic enantioselective C(sp3)–H functionalization involving radical intermediates
Recently, with the boosted development of radical chemistry, enantioselective functionalization of C(
sp
3
)–H bonds via a radical pathway has witnessed a renaissance. In principle, two distinct catalytic modes, distinguished by the steps in which the stereochemistry is determined (the radical formation step or the radical functionalization step), can be devised. This Perspective discusses the state-of-the-art in the area of catalytic enantioselective C(
sp
3
)–H functionalization involving radical intermediates as well as future challenges and opportunities.
Enantioselective functionalization of ubiquitous C(sp
3
)–H bonds via radical species has witnessed a renaissance in the past years. Here, the authors summarize the main achievements in the field by identifying two main reaction pathways determining the stereochemistry and give an outlook on future challenges and opportunities.
Journal Article
Cancer-derived exosomal miR-25-3p promotes pre-metastatic niche formation by inducing vascular permeability and angiogenesis
Cancer-derived exosomes are considered a major driver of cancer-induced pre-metastatic niche formation at foreign sites, but the mechanisms remain unclear. Here, we show that miR-25-3p, a metastasis-promoting miRNA of colorectal cancer (CRC), can be transferred from CRC cells to endothelial cells via exosomes. Exosomal miR-25-3p regulates the expression of VEGFR2, ZO-1, occludin and Claudin5 in endothelial cells by targeting KLF2 and KLF4, consequently promotes vascular permeability and angiogenesis. In addition, exosomal miR-25-3p from CRC cells dramatically induces vascular leakiness and enhances CRC metastasis in liver and lung of mice. Moreover, the expression level of miR-25-3p from circulating exosomes is significantly higher in CRC patients with metastasis than those without metastasis. Our work suggests that exosomal miR-25-3p is involved in pre-metastatic niche formation and may be used as a blood-based biomarker for CRC metastasis.
The mechanisms underlying pre-metastatic niche formation by cancer derived exosomes is unclear. Here they show that colorectal cancer (CRC) derived exosomal miR-25-3p promotes vascular leakiness and angiogenesis, CRC metastasis, and is upregulated in CRC pateints with metastasis, and suggest miR-25-3p as a biomarker for CRC metastasis.
Journal Article
Bioactive hierarchical silk fibers created by bioinspired self-assembly
Artificial recapitulation of the hierarchy of natural protein fibers is crucial to providing strategies for developing advanced fibrous materials. However, it is challenging due to the complexity of the natural environment. Inspired by the liquid crystalline spinning of spiders, we report the development of natural silk-like hierarchical fibers, with bundles of nanofibrils aligned in their long-axis direction, by self-assembly of crystallized silk fibroin (SF) droplets. The formation of self-assembled SF fibers is a process of coalesced droplets sprouting to form a branched fibrous network, which is similar to the development of capillaries in our body. The as-assembled hierarchical SF fibers are highly bioactive and can significantly enhance the spreading and growth of human umbilical vein endothelial cells compared to the natural SF fibers. This work could help to understand the natural silk spinning process of spiders and provides a strategy for design and development of advanced fibrous biomaterials for various applications.
The creation of silk fibres using bioinspired approaches is of interest for biomaterials development. Here, the authors report on the creation of mimetic hierarchical silk fibres by the rotational self-assembly of silk fibroin droplets and demonstrate the creation of bioactive silk materials.
Journal Article
Structural and Photophysical Properties of Methylammonium Lead Tribromide (MAPbBr3) Single Crystals
The structural and photophysical characteristics of MAPbBr
3
single crystals prepared using the inverse temperature crystallization method are evaluated using temperature-dependent X-ray diffraction (XRD) and optical spectroscopy. Contrary to previous research reports on perovskite materials, we study phase transitions in crystal lattice structures accompanied with changes in optical properties expand throughout a wide temperature range of 300–1.5 K. The XRD studies reveal several phase transitions occurred at ~210 K, ~145 K, and ~80 K, respectively. The coexistence of two different crystallographic phases was observed at a temperature below 145 K. The emission peaks in the PL spectra are all asymmetric in line shape with weak and broad shoulders near the absorption edges, which are attributed to the Br atom vacancy on the surface of the crystals. The time-resolved PL measurements reveal the effect of the desorption/adsorption of gas molecules on the crystal surface on the PL lifetimes. Raman spectroscopy results indicate the strong interplays between cations and different halide atoms. Lastly, no diamagnetic shift or split in emission peaks can be observed in the magneto-PL spectra even at an applied magnetic field up to 5 T and at a temperature as low as 1.5 K.
Journal Article