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1.
The hippocampus is crucial in learning, memory and emotion processing, and is involved in the development of different neurological and neuropsychological disorders. Several epigenetic factors, including DNA methylation, histone modifications and non-coding RNAs, have been shown to regulate the development and function of the hippocampus, and the alteration of epigenetic regulation may play important roles in the development of neurocognitive and neurodegenerative diseases. This review summarizes the epigenetic modifications of various cell types and processes within the hippocampus and their resulting effects on cognition, memory and overall hippocampal function. In addition, the effects of exposure to radiation that may induce a myriad of epigenetic changes in the hippocampus are reviewed. By assessing and evaluating the current literature, we hope to prompt a more thorough understanding of the molecular mechanisms that underlie radiation-induced epigenetic changes, an area which can be further explored.  相似文献   
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Skeletal muscle regeneration is highly dependent on the inflammatory response. A wide variety of innate and adaptive immune cells orchestrate the complex process of muscle repair. This review provides information about the various types of immune cells and biomolecules that have been shown to mediate muscle regeneration following injury and degenerative diseases. Recently developed cell and drug-based immunomodulatory strategies are highlighted. An improved understanding of the immune response to injured and diseased skeletal muscle will be essential for the development of therapeutic strategies.  相似文献   
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Clostridium difficile is a nosocomial pathogen that causes a serious toxin-mediated enteric disease in humans. Reducing C. difficile toxin production could significantly minimize its pathogenicity and improve disease outcomes in humans. This study investigated the efficacy of two, food-grade, plant-derived compounds, namely trans-cinnamaldehyde (TC) and carvacrol (CR) in reducing C. difficile toxin production and cytotoxicity in vitro. Three hypervirulent C. difficile isolates were grown with or without the sub-inhibitory concentrations of TC or CR, and the culture supernatant and the bacterial pellet were collected for total toxin quantitation, Vero cell cytotoxicity assay and RT-qPCR analysis of toxin-encoding genes. The effect of CR and TC on a codY mutant and wild type C. difficile was also investigated. Carvacrol and TC substantially reduced C. difficile toxin production and cytotoxicity on Vero cells. The plant compounds also significantly down-regulated toxin production genes. Carvacrol and TC did not inhibit toxin production in the codY mutant of C. difficile, suggesting a potential codY-mediated anti-toxigenic mechanism of the plant compounds. The antitoxigenic concentrations of CR and TC did not inhibit the growth of beneficial gut bacteria. Our results suggest that CR and TC could potentially be used to control C. difficile, and warrant future studies in vivo.  相似文献   
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In the present study, we report the synthesis of photoactive bismuth oxycarbonate (BOC, Bi2O2CO3) grafted NiFe layered double hydroxide (LDH) supported on g-C3N4 (15 wt% of g-C3N4) by coprecipitation method. The band gap of this photoactive material is determined to be 1.7 eV. The Bi2O2CO3 agglomerates are anchored on NiFe-LDH plates and g-C3N4 nanosheets intercalated between the LDH plates. This architecture helps in expediting electron transfer for hydrogen and oxygen evolution reactions. The pristine NiFe-LDH photoanode acquires bifunctional character because of Bi2O2CO3 agglomerates and g-C3N4 embedded in the architecture of BOC/NiFe-LDH@g-C3N4. This is found to be an efficient photoanode for oxygen evolution and photocathode for hydrogen evolution reactions. The water splitting process occurs along the heterojunction formed between g-C3N4 nanosheets and Bi2O2CO3 grafted NiFe-LDH. Further, an additional interfacial charge transfer aided by Bi2O2CO3 results in S-scheme mechanism, which enhances the rate of photoelectrochemical hydrogen and oxygen evolution reactions.  相似文献   
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A nanocomposite CuTi layered double hydroxide (LDH) supported on g-C3N4 (15 wt% of g-C3N4) is facilely synthesized by hydrothermal method. There are electrostatic interactions between positive layers of CuTi-LDH and negatively charged inner g-C3N4 sheets. The nanocomposite and its precursors are characterized through various analytical techniques, which affirmed the presence of both g-C3N4 and CuTi-LDH characteristic features. The pore-enriched hybrid geometry of CuTi-LDH@g-C3N4 with high specific surface area (146 m2/g), and suitable band gap of 2.46 eV enables the nanocomposite to act as both an electrocatalyst and photoelectrocatalyst for oxygen evolution reaction (OER). Both the electrochemical and photoelectrochemical studies are done using 1 M KOH (pH = 13.6) with applied potential of ?0.2 V to 1.5 V vs. Ag/AgCl. The onset potential of CuTi-LDH@g-C3N4 for OER appears at η = 0.36 V in dark and η = 0.32 V under visible light illumination of 30 min. Also, Mott-Schottky analysis shows n-type semiconductor behaviour for CuTi-LDH@g-C3N4 and its precursors. The photoelectrochemical water oxidation proceeds by charge transfer across a Type II heterojunction formed between the CuTi-LDH and g-C3N4 materials.  相似文献   
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Given the prevalence of online media today, credibility continues to be a popular subject of empirical research. However, studies examining the effects of discrediting strategies are rare. This issue is significant given the popularity of online media and the ease of such sources to spread misinformation. Therefore, the present study examines the effects of attacking the expertise and trustworthiness of a proponent of a major social issue. Results showed that support as well specific combinations of discrediting attack strategies significantly reduced message board readers' perceptions of the proponent's credibility. In addition, attacks on either the proponent's expertise or trustworthiness resulted in a reduced likelihood of readers taking action with respect to the issue.  相似文献   
9.
An emerging trend in Canada is the creation of community energy plans, where decisions that used to be left to regional level energy agencies or private individuals are now being considered at the community level. A desire to reduce greenhouse gas emissions and to become more energy self-sufficient is driving this change. Theoretically, local level management is desirable because it achieves these goals through improvements in the three areas of energy efficiency, energy conservation and switching to renewable energy sources. The analysis of 10 of the first community energy plans in Canadian communities, ranging in population size from 500 to one million, finds that communities are choosing policies and programs centred on increasing energy efficiency and conservation while renewable energy receives much less attention. Municipal operations were called upon to set higher targets than the general community. Communities that recognized the substantial potential of renewable energy often focused on technologies that the municipal sector could implement, such as bio-fuels for their transportation fleet. Wind, passive solar design, solar photovoltaics and solar thermal options were only recommended in a few cases. Overall, only one of the five larger communities (Calgary) recommended implementing multiple renewable energy technologies while three of the five smaller communities proposed multiple renewable energy sources. The implication is that smaller and more remote communities may be the most willing to lead in the planned introduction of renewable energy systems.  相似文献   
10.
A light-activated NO donor, [Mn(PaPy3)(NO)]ClO4 (1a), has been incorporated into HEMA-based polymer hydrogel and the nitrosyl-polymer conjugate materials 1ax · HG and 1ax · HGMB have been characterized. The NO releasing properties and antibacterial capabilities of these materials in conjunction with growth attenuators such as hydrogen peroxide and methylene blue (MB) are reported. Since the nitrosyl releases NO only upon exposure to light, materials like 1ax · HGMB could be used as wound dressings that deliver NO under controlled conditions.  相似文献   
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