Microwave‐driven strategy shows many advantages including selective energization, uniform heating, and high penetration depth, which is a hot topic in wireless actuators. Understanding microwave ...stimulus‐response mechanisms is the key to developing universal construction strategies for advanced microwave‐driven actuators. Herein, reduced graphene oxide (rGO) with specified dielectric genes and thermal properties is implanted into the shape memory polymer, liquid crystal elastomer (LCE) as an example, to construct soft, reversible, and sensitive microwave actuators. Based on the analysis of microstructure and dielectric properties, LCE‐rGO composites exhibit excellent polarization relaxation‐dominated dielectric loss and electromagnetic (EM) energy conversion ability. The maximum dielectric loss factor (ε″) and loss tangent (tan δe) of LCE‐rGO are dramatically increased by 216% and 87.5% compared to pure LCE, respectively, and the optimum apparent energy harvest efficiency is 19.4 times higher than that of LCE. In addition, the implantation of rGO significantly lowers the microwave actuation threshold of LCE‐rGO composites and reinforces their stimulus‐response capacity. Response time under 750 W microwave irradiation of LCE‐rGO is shortened to <10s. These findings can provide a solid basis for the design and fabrication of highly efficient microwave stimuli‐responsive polymers and enlighten a new approach to wireless actuated smart devices.
Graphene‐implanted shape memory polymer (LCE‐rGO) is prepared, which can convert microwave energy into thermal energy through enhanced polarization genes dominated dielectric loss properties. Synergistic with excellent conduct heat capability of rGO, it triggers the inherent nematic‐isotropic phase transition of the LCE. As microwave‐driven composites, The LCE‐rGO is expected to act as kinetic components to provide mechanical energy for wireless drive equipment.
The aim of this study was to analyze the present situation of Ureaplasma urealyticum (UU), Chlamydia trachomatis (CT), Mycoplasma genitalium (MG) and Neisseria gonorrhoeae (NG) infections among ...obstetrics and gynecological outpatients in southwest China.
A total of 3225 urogenital swabs were included in this study. All swabs were tested by RNA-based simultaneous amplification and testing (SAT) methods. Routine analysis of leucorrhea smear and drug susceptibility were performed in UU positive patients.
Of these 3225 outpatients, the positive rate was 27.07% for UU, 4.99% for CT, 3.10% for MG, and 0.09% for NG. UU, CT, and MG infections were more common in women of reproductive age (aged 25-34 years), while NG infection was more prominent in women aged 30-34 years and over 40 years. Overall, the infection rate of UU was significantly higher than that of the other three infections, and UU also played a major role even in the mixed infections. 65.07% of the UU positive patients had negative results on routine leucorrhea smear analysis, and the remaining patients may have bacterial vaginitis (15.79%), fungal vaginitis (11.48%), trichomonas vaginitis (0.96%) or other vaginal inflammation (6.70%). We have observed that maternal UU infection can lead to low birth weight, neonatal pneumonia, and premature delivery. The results of the drug susceptibility test of UU showed a higher sensitivity to pristinamycin, doxycycline, tetracycline, clarithromycin, and josamycin (100%, 97.0%, 96.4%, 95.9%, and 95.3%, respectively), and lower sensitivity to ciprofloxacin and ofloxacin (2.4% and 4.7% respectively).
This study could contribute to a better understanding of the current epidemiological features of UU, CT, MG, and NG among obstetrics and gynecological outpatients in southwest China, and thus facilitate to development of the more effective intervention, prevention, and treatment of reproductive tract infection.
DNA repair pathways are triggered to maintain genetic stability and integrity when mammalian cells are exposed to endogenous or exogenous DNA-damaging agents. The deregulation of DNA repair pathways ...is associated with the initiation and progression of cancer. As the primary anti-cancer therapies, ionizing radiation and chemotherapeutic agents induce cell death by directly or indirectly causing DNA damage, dysregulation of the DNA damage response may contribute to hypersensitivity or resistance of cancer cells to genotoxic agents and targeting DNA repair pathway can increase the tumor sensitivity to cancer therapies. Therefore, targeting DNA repair pathways may be a potential therapeutic approach for cancer treatment. A better understanding of the biology and the regulatory mechanisms of DNA repair pathways has the potential to facilitate the development of inhibitors of nuclear and mitochondria DNA repair pathways for enhancing anticancer effect of DNA damage-based therapy.
In the recent years, polyoxometalate (POM) encapsulated metal–organic framework (MOF) composites have attracted much attention in photocatalysis. Both POMs and MOFs have been attracting immense ...attention in this area. Furthermore, in order to promote charge transfer and separation between POMs and MOFs, theoretical and experimental analysis can be applied to match their energy levels; however, their individual applications are hindered by several defects, such as poor visible-light utilization efficiency. The combination of MOFs and POMs can benefit from the virtues of both POMs and MOFs while avoiding the drawbacks of them. Notably, MOFs with high specific surface area and long-range ordered structure ensure a uniform distribution of POMs, which cannot only prevent the self-aggregation of POMs but also allow the exposure of more active sites for catalysis. POM@MOF composites have been identified as promising materials for photocatalysis because of their diverse unique advantages, such as ultrahigh porosity, large specific surface area, and excellent electron redox transformation. In this work, we present an overview of the developments in POM@MOF composite-based catalysts for visible light induced photocatalysis. The strategies employed for the preparation of POM@MOF composites are summarized and discussed with a particular focus on the stability of such materials. The representative works on photocatalytic water splitting, CO2 reduction, degradation of pollutants, and selective oxidation of organics are highlighted. Special attention is paid to the synergistic effects between the MOF and POM that result in an enhanced performance. Besides, the stability and reusability of these materials are also discussed. Also, the unsolved problems and development opportunities of POM@MOF composites in the field of photocatalysis are proposed.
The pine wood nematode Bursaphelenchus xylophilus is a destructive pest of Pinus trees worldwide and lacks effective control measures. Screening for nematotoxic proteins has been undertaken to ...develop new strategies for nematode control. The results of the present study provided initial insights into the responses of B. xylophilus exposed to a nematotoxic cytolytic-like protein (CytCo) based on transcriptome profiling. A large set of differentially expressed genes (DEGs = 1265) was found to be related to nematode development, reproduction, metabolism, motion, and immune system. In response to the toxic protein, B. xylophilus upregulated DEGs encoding cuticle collagens, transporters, and cytochrome P450. In addition, many DEGs related to cell death, lipid metabolism, major sperm proteins, proteinases/peptidases, phosphatases, kinases, virulence factors, and transthyretin-like proteins were downregulated. Gene Ontology enrichment analysis showed that the CytCo treatment substantially affected DEGs involved in muscle contraction, lipid localization, and the mitogen-activated protein kinase cascade. The pathway richness of the Kyoto Encyclopedia of Genes and Genomes showed that the DEGs were concentrated in lysosomes and involved in fatty acid degradation. Weighted co-expression network analysis indicated that the hub genes affected by CytCo were associated with the nematode cuticular collagen. These results showed that CytCo toxin interferes with gene expression to exert multiple nematotoxic effects, thereby providing insights into its potential use in pine wood nematode control.
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•The historical development of the Z-scheme photocatalytic system is presented.•The recent crucial applications and progress of Z-scheme photocatalysts are presented.•The charge ...carrier migration process and photocatalytic reaction pathways of Z-scheme photocatalysts are discussed.•Exciting perspectives on the challenges of this emerging research direction are presented.
Artificial Z-scheme photocatalysis has become a potential solution for resisting environmental degradation and to the worldwide energy shortage because they can effectively promote the separation of photogenerated electron-hole pairs and optimize the oxidation and reduction ability of the photocatalytic system. Currently, the application of Z-scheme photocatalysts in environmental remediation and energy conversion have ushered in a climax over the past several years. Hence, it is the ripe and right period to provide a comprehensive and state-of-the-art review on the latest achievements and the future trends of Z-scheme photocatalysis. Here, we begin with a review about the historical development of the Z-scheme photocatalytic system from redox-mediator Z-scheme photocatalytic system to current direct Z-scheme photocatalytic system. Then the latest research activities on the application of Z-scheme photocatalysts for target organic pollutants degradation, heavy metal ion redox, micro-organisms inactivation, water-splitting, H2 and O2 evolution are systematically summarized and highlighted. Many recent advances in Z-scheme photocatalysis have been achieved by increasing the absorption region of visible light or promoting the separation and transfer of photogenerated charge carriers to achieve optimal photocatalytic performance. Especially, we discuss the charge carrier transfer process and photocatalytic reaction pathways of key aspects of Z-scheme photocatalysts. Finally, conclusions and inspiring perspectives on the challenges of this emerging research direction are presented. We desire that insights and up-to-date information in this overview will prompt the scientific community to fully explore the potential of Z-scheme photocatalytic systems in environmental remediation and energy conversion.
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•The water splitting technology and its need for current energy demand are introduced.•The mechanism of water splitting on NiFe-based catalysts is discussed in depth.•The necessity of ...LDH phase formation under OER conditions are emphasized.•The role of Fe3+ in improving the water splitting performance of NiFe-based catalysts and the advantages over other trivalent cations are clarified.
NiFe-based compounds have received increasing attention due to their low cost, availability, as well as excellent H2 evolution reaction (HER) and the O2 evolution reaction (OER) catalytic properties. Although it is agreed that the implementation of high activity, the co-existence of Ni and Fe is essential, the identification of active sites and the mechanism of water splitting in NiFe-based compounds have long been controversial. This review focuses on the catalytic centers of NiFe-based oxides/(oxy)hydroxides and related mechanism in alkaline water oxidation process from the perspective of thermodynamics and kinetics. Furthermore, NiFe layered double hydroxides (NiFe LDHs) are introduced separately, emphasizing the necessity of LDH phase formation during water splitting. The review highlights the roles of Fe3+ and the third transition metal Co in NiFe-based catalysts. Finally, a brief perspective on NiFe-based catalysts is proposed. This review will be a good complement to the existing literatures and will contribute to a better study of NiFe-based catalysts.
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•Reveals the Yellow River Basin’s LULC dynamics and issues over the past 20 years.•Considers multi-dimensions: intertype conversion, space–time and time–space changes.•Advantaged ...models to explore the LULC driving factors and future spatial distribution.•Improves methods to assess and predict ecosystem services on various scales.•Intensified urban sprawl, grassland degradation, and reduced ecosystem services in 2030.
Analyzing LULC dynamics and ecosystem services is of great significance for both revealing the potential issues of surface change and creating ecological awareness and actions. The Yellow River Basin is a vast geographical unit integrating fragile ecosystems and crucial socio-economic systems, in which development and conservation have coexisted and coevolved over decades. Here, we explored the evolution characteristics of land use/land cover (LULC) changes from 2000 to 2020 and predicted the future changes in 2030. On this basis, the ecosystem services were assessed and predicted correspondingly on established grids, administrative divisions, and the basin. Analyses show remarkable progress in reforestation and water protection and great challenges of grassland protection. Cropland keeps declining at a reduced change rate from 1.7% to 0.7%, with its developed and occupied rates intensifying. Grassland degradation and transition are increasingly severe, with its reduction rate doubling in the second decade. Large-scale and repeated conversions between cropland and grassland indicate their spatial conflicts in the upstream fragile zone but fail to be mitigated by existing policies. Land use intensifies over time and successively from upstream to downstream in space, with construction land increasing by 23.2% and 68.2% in the past two decades, respectively. Based on predictions by the Patch-generating Land Use Simulation model, we found higher risks of downstream cropland loss and grassland degradation in 2030. Construction land was estimated to increase dramatically by 34.5%. The basin’s total value of ecosystem services (ESV) was estimated to increase by 13.87 billion CNY during 2000–2010 and decrease by 5.27 billion CNY during 2010–2020, likely to reduce by 5.40 billion CNY in 2030. Values of provisioning services, regulating services, supporting services, and cultural services change follow the same inverted V-shape changes as the ESV, anticipated to decline by 0.5%, 0.4%, 1.6%, and 1.1%, respectively in 2030. This study on the river basin offers valuable insights and implications on land use, ecology protection, and sustainable development via revealing the LULC change issues, assessing and predicting the ecological status.
This study is aimed to examine the association between umbilical cord blood (UCB) derived exosomal microRNA (miRNA) with preeclampsia (PE) and to further explore the mechanism of a key differential ...gene (hsa-miR-125a-5p) in preeclampsia. Umbilical cord blood exosomal miRNA(exo-miRNA) from normal pregnant women and pregnant women with preeclampsia was processed via miRNA sequencing. Quantitative real-time polymerase chain reaction (QRT-PCR) was performed to assess the expression of miR-125a-5p in normal and PE placental tissues and peripheral blood derived exosomes in the third trimester. Human trophoblast cell line HTR8/SVneo was assigned as the negative control and miR-125a-5p mimics. QRT-PCR and Western blot were performed to identify the expressions of miR-125a-5p and vascular endothelial growth factor A (VEGFA). CCK8, flow cytometry, wound-healing and Transwell assays were used to analyze the effect of miR-125a-5p on HTR8/SVneo cell migration, proliferation, and cycle distribution. Tube formation was performed to estimate the angiogenesis ability of miR-125a-5p on HUVECs. In conclusion, miR-125a-5p expression in PE placental tissues was higher than in normal subjects, while the expression of VEGFA was lower in PE placental tissues. We then compared the miR-125a-5p mimics group with the negative control group and found that in the mimics group, the cell migration, proliferation and angiogenesis abilities were decreased, and more cells were arrested in the S stage. Our study systematically profiled the UCB exo-miRNA in normal and PE pregnant women and demonstrated that dysregulation of miR-125a-5p might affect HTR8/SVneo cell proliferation and migration and inhibit angiogenesis by regulating VEGFA, indicating that miR-125a-5p is involved in the progression of PE.
•Obtained the umbilical vein plasma exosomal microRNA expression profile in preeclampsia and normal pregnant women.•Exosome-delivered miR-125a-5p is highly expressed in umbilical vein plasma and peripheral blood plasma of preeclampsia.•miR-125a-5p may play a role in the pathogenesis of preeclampsia.
Intrastriatal injection of mesencephalic astrocyte-derived neurotrophic factor (MANF) protein has been shown to provide neuroprotective and neurorestorative effects in a 6-hydroxydopamine (6-OHDA) - ...lesioned rat model of Parkinson's disease. Here, we used an adeno-associated virus serotype 9 (AAV9) vector to deliver the human MANF (hMANF) gene into the rat striatum 10days after a 6-OHDA lesion to examine long-term effects of hMANF on nigral dopaminergic neurons and mechanisms underlying MANF neuroprotection. Intrastriatal injection of AAV9-hMANF vectors led to a robust and widespread expression of the hMANF gene in the injected striatum up to 24weeks. Increased levels of hMANF protein were also detected in the ipsilateral substantia nigra. The hMANF gene transfer promoted the survival of nigral dopaminergic neurons, regeneration of striatal dopaminergic fibers and an upregulation of striatal dopamine levels, resulting in a long-term improvement of rotational behavior up to 16weeks after viral injections. By using SH-SY5Y cells, we found that intra- and extracellular application of MANF protected cells against 6-OHDA-induced toxicity via inhibiting the endoplasmic reticulum stress and activating the PI3K/Akt/mTOR pathway. Our results suggest that AAV9-mediated hMANF gene delivery into the striatum exerts long-term neuroprotective and neuroregenerative effects on the nigrostriatal dopaminergic system in parkinsonian rats, and provide insights into mechanisms responsible for MANF neuroprotection.
•Intrastriatal delivery of AAV9-hMANF leads to robust striatal transduction.•Intrastriatal delivery of AAV9-hMANF reduces rotational scores of parkinsonian rats.•Intrastriatal delivery of AAV9-hMANF promotes the survival of nigral DA neurons.•Intracellular overexpression of MANF protects SH-SY5Y cells via inhibiting ER stress.•Extracellular rhMANF protein protects SH-SY5Y cells via the PI3K/Akt/mTOR pathway.
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