A new Mn(II) metal–organic framework (MOF) 1 was synthesized by the combination of 4,4,4-trifluoro-1-(4-(pyridin-4-yl)phenyl)butane-1,3-dione (L) and Mn(OAc)2 in solution. 1 features a ...threefold-interpenetrating NbO net containing honeycomb-like channels, in which the opposite Mn(II)···Mn(II) distance is 23.5075(10) Å. Furthermore, 1 can be an ideal platform to support Pd–Au bimetallic alloy nanoparticles to generate a composite catalytic system of Pd–Au@Mn(II)-MOF (2). 2 can be a highly active bifunctional heterogeneous catalyst for the one-pot tandem synthesis of imines from benzyl alcohols and anilines and from benzyl alcohols and benzylamines.
An ideal bone repair scaffold is expected to possess superior architectural characteristics to facilitate the adhesion, proliferation, and migration of bone‐repair‐related cells, while excluding ...nonosteogenic cells and fibrous tissues from interfering with normal bone regeneration. Unfortunately, such scaffold material has rarely been reported. Herein, nanocomposite scaffolds with a radially ordered porous structure are presented, manufactured using a modified directional freeze‐casting method, and are promising bone defect repair materials to satisfy this requirement. The prepared nanocomposite scaffolds consist of a natural bio‐macromolecule, chitosan, and bioactive hydroxyapatite nanoparticles derived from porcine cortical bone, demonstrating favorable biocompatibility and biological functions. Both in vitro cell studies and in vivo animal studies reveal the great superiority of the radially oriented porous structure of the scaffolds in guiding bone regeneration, while simultaneously preventing the invasion of surrounding nonosteogenic cells and fibrous tissue, compared to the axially oriented porous structure. This work indicates the distinctive potential of radially oriented porous scaffolds for repairing tabular and lacunar bone defects.
A nanocomposite scaffold with a radially oriented porous structure is engineered via a modified freeze‐casting method. The unique structural feature renders the nanocomposite scaffold with great superiority in guiding the infiltration and migration of bone‐repair‐related cells into the scaffold, while preventing the invasion of surrounding nonosteogenic cells and fibrous tissues from interfering with the normal bone regeneration process.
Sleep disturbances and dementia are two common and significant health problems in older adults. Investigations suggest that sleep disturbances might increase the risk of dementia. The aim of the ...present study was to systematically review and meta-analyze the predictive roles of overall sleep disturbances, their subtypes (e.g., insomnia, sleep disordered breathing SDB), and other sleep problems (e.g., excessive daytime sleepiness, sleep-related movement disorder, circadian rhythm sleep disorder, and nonspecific sleep problems) in incident all-cause dementia and Alzheimer's disease (AD) and vascular dementia subtypes. We performed a systematic search of the PubMed, EMBase, ISI Web of Science, and PsycINFO databases for longitudinal studies that were published up to October 28, 2016. A total of 12,926 papers were retrieved. Eighteen longitudinal studies that included 246,786 subjects at baseline and 25,847 dementia cases after an average 9.49 y of follow-up were eligible for inclusion. Compared with individuals without sleep disturbances, subjects who reported sleep disturbances had a higher risk of incident all-cause dementia, AD, and vascular dementia. The subgroup analysis showed that insomnia increased the risk of AD but not vascular or all-cause dementia. In contrast, SDB was associated with a higher incidence of all-cause dementia, AD, and vascular dementia. This meta-analysis suggests that sleep disturbances may predict the risk of incident dementia. Moreover, insomnia was associated only with incident AD, and SDB was a risk factor of all-cause dementia, AD, and vascular dementia. However, sleep disturbances were evaluated mainly based on self-reports, and some confounders may mediate the relationship between sleep disturbances and dementia. Therefore, the results should be further validated. In summary, these findings may help identify individuals who are at risk for dementia and optimize early prevention strategies.
Abstract
Light-induced 2 + 2 cycloaddition is the most straightforward way to generate cyclobutanes, which are core structures of many natural products, drugs and bioactive compounds. Despite ...continuous advances in selective 2 + 2 cycloaddition research, general method for intermolecular photocatalysis of acyclic olefins with specific regio- and diastereoselectivity, for example,
syn
-head-to-head (
syn
-HH) cyclobutane derivatives, is still lack of development but highly desired. Herein, we report a cage-confined photocatalytic protocol to enable unusual intermolecular 2 + 2 cycloaddition for
α,β
-unsaturated carbonyl compounds. The
syn
-HH diastereomers are readily generated with diastereoselectivity up to 99%. The cage-catalyst is highly efficient and robust, covering a diverse substrate range with excellent substituent tolerance. The mimic-enzyme catalysis is proposed through a host-guest mediated procedure expedited by aqueous phase transition of reactant and product, where the supramolecular cage effect plays an important role to facilitate substrates inclusion and pre-orientation, offering a promising avenue for general and eco-friendly cycloaddition photocatalysis with special diastereoselectivity.
Abstract
Background
Understanding the long-term effects of coronavirus disease 2019 (COVID-19) on cognitive function is essential for monitoring the cognitive decline in the elderly population. This ...study aims to assess the current cognitive status and the longitudinal cognitive decline in elderly patients recovered from COVID-19.
Methods
This cross-sectional study recruited 1539 COVID-19 inpatients aged over 60 years who were discharged from three COVID-19-designated hospitals in Wuhan, China, from February 10 to April 10, 2020. In total, 466 uninfected spouses of COVID-19 patients were selected as controls. The current cognitive status was assessed using a Chinese version of the Telephone Interview of Cognitive Status-40 (TICS-40) and the longitudinal cognitive decline was assessed using an Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Cognitive assessments were performed 6 months after patient discharge.
Results
Compared with controls, COVID-19 patients had lower TICS-40 scores and higher IQCODE scores TICS-40 median (IQR): 29 (25 to 32) vs. 30 (26 to 33),
p
< 0.001; IQCODE median (IQR): 3.19 (3.00 to 3.63) vs. 3.06 (3.00 to 3.38),
p
< 0.001. Severe COVID-19 patients had lower TICS-40 scores and higher IQCODE scores than non-severe COVID-19 patients TICS-40 median (IQR): 24 (18 to 28) vs. 30 (26 to 33),
p
< 0.001; IQCODE median (IQR): 3.63 (3.13 to 4.31) vs. 3.13 (3.00 to 3.56),
p
< 0.001 and controls TICS-40 median (IQR): 24 (18 to 28) vs. 30 (26 to 33),
p
< 0.001; IQCODE median (IQR) 3.63 (3.13 to 4.31) vs. 3.06 (3.00 to 3.38),
p
< 0.001. Severe COVID-19 patients had a higher proportion of cases with current cognitive impairment and longitudinal cognitive decline than non-severe COVID-19 patients dementia: 25 (10.50 %) vs. 9 (0.69 %),
p
< 0.001; Mild cognitive impairment (MCI): 60 (25.21 %) vs. 63 (4.84 %),
p
< 0.001 and controls dementia: 25 (10.50 %) vs. 0 (0 %),
p
< 0.001; MCI: 60 (25.21 %) vs. 20 (4.29 %),
p
< 0.001). COVID-19 severity, delirium and COPD were risk factors of current cognitive impairment. Low education level, severe COVID-19, delirium, hypertension and COPD were risk factors of longitudinal cognitive decline.
Conclusions
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with an increased risk of long-term cognitive decline in elderly population. COVID-19 patients, especially severe patients, should be intensively monitored for post-infection cognitive decline.
Polyimide (PI) aerogels have attracted great attention owing to their low density and excellent thermal stability. However, hydrophobic surface modification is required for PI aerogels to improve ...their ability in oil/water separation due to their amphiphilic characteristic. Two-dimensional MXenes (transition metal carbides/nitrides) can be utilized as nanofillers to enhance the properties of polymers because of their unique layered structure and versatile interface chemistry. Herein, the robust, lightweight, and hydrophobic PI/MXene three-dimensional architectures were fabricated via freeze-drying of polyamide acid/MXene suspensions and thermal imidization. Polyamide acid was synthesized using N-N-dimethylacetamide and 4,4′-oxydianiline. MXene (Ti3C2T x ) dispersion was obtained via the etching of Ti3AlC2 and ultrasonic exfoliation. Taking advantage of the strong interaction between PI chains and MXene nanosheets, the interconnected, highly porous, and hydrophobic PI/MXene aerogels with low density were fabricated, resulting in the improved compressive performance, remarkable oil absorption capacity, and efficient separation of oil and water. For the PI/MXene-3 aerogel (weight ratio, 5.2:1) without any surface modification, the water contact angle was 119° with a density of 23 mg/cm3. This aerogel can completely recover to its original height after 50 compression–release cycles, exhibiting superelasticity and exceptional fatigue-resistant ability. It also showed high absorption capacities to various organic liquids ranging from approximately 18 to 58 times of their own weight. This hybrid aerogel can rapidly separate the chloroform, soybean oil, and liquid paraffin from the water–oil system. The thermally stable hybrid aerogel also exhibited excellent fire safety properties and outstanding reusability under an extreme environment.
A three‐plasmon hybrid, in which core–shell Au@Cu2−xS hybrids are bonded with ultrathin Ti3C2Tx MXene, is prepared for high‐efficiency photothermal conversion and membrane‐based solar water ...evaporation for the first time. The MXene/Au nanorod@Cu2−xS hybrids display excellent photothermal conversion efficiency under irradiation of an 808 laser, causing by the three‐plasmon‐induced synergistic plasmonic absorption and heating effects as well as the multichannel charge transfer between the components. Then, Au nanosphere@Cu2−xS and Au nanorod@Cu2−xS hybrids are mixed and combined with MXene to serve as the membrane material, which shows excellent light absorption ranging from ultraviolet to near‐infrared region. By transferring the membrane materials on a hydrophilic cotton piece, the as‐prepared photothermal membrane displays a high evaporation rate of 2.023 kg m−2 h−1 and light‐to‐heat conversion efficiency of 96.1% under 1‐sun irradiation due to the synergistic photothermal conversion and over 96% of solar light absorption efficiency. Furthermore, a home‐made solar evaporation device enabling automatic inflow of untreated water and outflow of evaporated water is designed based on the principles of liquid pressure and connectors. The seawater desalination and sewage treatment experiments performed on the device and membrane indicate the great potential in solar‐light‐driven water purification and drinkable water generation.
The heavy metal zinc (Zn) is known to be transmitted in the food chain; however, the effect of Zn stress on beans and herbivorous insects is largely unclear. This study aimed to investigate the ...resistance of broad bean plants to Zn stress and the consequent changes in their physiological and biochemical metabolism by simulating heavy metal pollution in soil. Simultaneously, the effects of aphid progeny treated with different Zn concentrations on the expression of carbohydrate and related genes were analyzed. The results showed that Zn had no effect on the germination rate of broad beans, but other effects mainly manifested as follows. (1) Chlorophyll content decreased. (2) The total soluble sugar and Zn content in stems and leaves increased with increasing Zn content. (3) The proline content first increased and then decreased with increasing Zn content. (4) The height of the seedlings indicates that low concentrations promote growth and high concentrations inhibit growth. In addition, only the first-generation fecundity decreased significantly when aphids fed on heavy metal broad beans. Continuous high Zn levels increase the trehalose content of aphid F1 and F2, while F3 decreases. These results can not only provide a theoretical basis for exploring the impact of soil heavy metal pollution on ecosystems but also preliminarily evaluate the possibility of broad beans as a means of pollution remediation.
A new composite Au@Cu(II)-MOF catalyst has been synthesized via solution impregnation and full characterized by HRTEM, SEM-EDS, XRD, gas adsorption–desorption, XPS, and ICP analysis. It has been ...shown here that the Cu(II)-framework can be a useful platform to stabilize and support gold nanoparticles (Au NPs). The obtained Au@Cu(II)-MOF exhibits a bifunctional catalytic behavior and is able to promote selective aerobic benzyl alcohol oxidation–Knoevenagel condensation in a stepwise way.
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