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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
2.
Commault C. Dion J.-M. Sename O. Motyeian R. 《Automatic Control, IEEE Transactions on》2002,47(12):2074-2079
3.
A class of uncertain time-delay systems containing a saturating actuator is considered. These systems are characterized by delayed state equations (including a saturating actuator) with norm-bounded parameter uncertainty (possibly time varying) in the state and input matrices. The delay is assumed to be constant bounded but unknown. Using a Razumikhin approach for the stability of functional differential equations, upper bounds on the time delay are given such that the considered uncertain system is robustly stabilizable, in the case of constrained input, via memoryless state feedback control laws. These bounds are given in terms of solutions of appropriate finite dimensional Riccati equations 相似文献
4.
A simple tutorial introduction to the geometric theory of linear multivariable control is presented. This corresponds to approximately three two-hour lectures in a graduate-level course. The authors emphasise the intuitive control interpretation of the main geometric concepts. To this end, the authors focus interest on trajectory formulation for subspace invariance and discrete-time interpretation of the basic subspaces and their construction algorithms. Application of geometric theory for solving the disturbance decoupling problem is illustrated via two pedagogical examples 相似文献
5.
Blends were prepared of styrene–acrylonitrile–fumaronitrile (SANFN) terpolymers with styrene–acrylonitrile (SAN) copolymers and of SANFN terpolymers with SANFN terpolymers of different compositions. Miscibility was determined by differential scanning calorimetry. For three SANFN terpolymer compositions containing 11–17% fumaronitrile, a range of miscible SAN copolymers was defined. The miscibility can be predicted by using a Flory–Huggins-type mean-field approach. 相似文献
6.
Examined the relation between gender and reactions to different styles of advertising tobacco and alcohol products among 41 females and 34 males (aged 12–16 yrs) and their parents (39 mothers and 36 fathers). Self-monitoring was also examined as a possible correlate. Ss rated magazine advertisements oriented toward the product's image or qualities. Girls liked image-oriented advertisements more and perceived them to be more persuasive than quality-oriented advertising. This gender difference was not observed among adults. All Ss liked image-oriented more than quality-oriented advertising. Moreover, image-oriented advertisements were seen as more persuasive than quality-oriented advertisements by girls' parents who were high in self-monitoring. Results suggest that girls in early adolescence may be particularly attentive to image-oriented commercials that portray smoking and drinking as desirable behaviors. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
P.J. Poole S. Charbonneau M. Dion G.C. Aers M. Buchanan R.D. Goldberg I.V. Mitchell 《Photonics Technology Letters, IEEE》1996,8(1):16-18
A technique for fabricating many different wavelength lasers on the same wafer has been developed. High energy ion implantation was used to selectively blue shift the emission wavelength of an InP-based quantum well laser structure. This structure was then processed into fully functional broad-area lasers whose current threshold was unaffected by the implantation process, indicating extremely high material quality after bandgap-shifting. This process has the potential for the integration of not only different wavelength lasers, but also other devices, such as waveguides, detectors, modulators, etc., on a single wafer. 相似文献
8.
9.
Natalia Ziemkiewicz Genevieve Hilliard Nicholas A. Pullen Koyal Garg 《International journal of molecular sciences》2021,22(6)
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
10.
Natasha M. van Poppelen Jolique A. van Ipenburg Quincy van den Bosch Jolanda Vaarwater Tom Brands Bert Eussen Frank Magielsen Hendrikus J. Dubbink Dion Paridaens Erwin Brosens Nicole Naus Annelies de Klein Emine Kili Robert M. Verdijk 《International journal of molecular sciences》2021,22(11)
The aim of this study was exploration of the genetic background of conjunctival melanoma (CM) and correlation with recurrent and metastatic disease. Twenty-eight CM from the Rotterdam Ocular Melanoma Study group were collected and DNA was isolated from the formalin-fixed paraffin embedded tissue. Targeted next-generation sequencing was performed using a panel covering GNAQ, GNA11, EIF1AX, BAP1, BRAF, NRAS, c-KIT, PTEN, SF3B1, and TERT genes. Recurrences and metastasis were present in eight (29%) and nine (32%) CM cases, respectively. TERT promoter mutations were most common (54%), but BRAF (46%), NRAS (21%), BAP1 (18%), PTEN (14%), c-KIT (7%), and SF3B1 (4%) mutations were also observed. No mutations in GNAQ, GNA11, and EIF1AX were found. None of the mutations was significantly associated with recurrent disease. Presence of a TERT promoter mutation was associated with metastatic disease (p-value = 0.008). Based on our molecular findings, CM comprises a separate entity within melanoma, although there are overlapping molecular features with uveal melanoma, such as the presence of BAP1 and SF3B1 mutations. This warrants careful interpretation of molecular data, in the light of clinical findings. About three quarter of CM contain drug-targetable mutations, and TERT promoter mutations are correlated to metastatic disease in CM. 相似文献