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981.
We demonstrate simultaneous generation, propagation and detection of optical vortices using all fiber-optic system. A fiber-optic Y-coupler was used for generating spherical and doughnut beams, simultaneously. Gaussian (TEM00) beam emitted from CW red He-Ne laser is coupled into the fiber coupler and is converted into vortex beam via second arm of fiber which propagates with azimuthal phase dependence having well defined orbital angular momentum. The phase structure of vortex beam was detected by interfering both the beams using simple fiber-optic interferometer. The present all fiber-optic system might find application for detecting, sensing physical parameters and is simple and cost effective for generating and detecting optical vortices. 相似文献
982.
Anita Gharekhan Ashok N. Oza M. B. Sureshkumar Asima Pradhan Prasanta K. Panigrahi 《Pramana》2010,75(6):1281-1286
Fluorescence characteristics of human breast tissues are investigated through wavelet transform and principal component analysis
(PCA). Wavelet transform of polarized fluorescence spectra of human breast tissues is found to localize spectral features
that can reliably differentiate different tissue types. The emission range in the visible wavelength regime of 500–700 nm
is analysed, with the excitation wavelength at 488 nm using laser as an excitation source, where flavin and porphyrin are
some of the active fluorophores. A number of global and local parameters from principal component analysis of both high- and
low-pass coefficients extracted in the wavelet domain, capturing spectral variations and subtle changes in the diseased tissues
are clearly identifiable. 相似文献
983.
Anita Patel Gautam Pulugundla Sergey Smolentsev Mohamed Abdou Rajendraprasad Bhattacharyay 《Theoretical and Computational Fluid Dynamics》2018,32(2):165-178
Following the magnetohydrodynamic (MHD) code validation and verification proposal by Smolentsev et al. (Fusion Eng Des 100:65–72, 2015), we perform code to code and code to experiment comparisons between two computational solvers, FLUIDYN and HIMAG, which are presently considered as two of the prospective CFD tools for fusion blanket applications. In such applications, an electrically conducting breeder/coolant circulates in the blanket ducts in the presence of a strong plasma-confining magnetic field at high Hartmann numbers, \(\textit{Ha}\) (\(\textit{Ha}^2\) is the ratio between electromagnetic and viscous forces) and high interaction parameters, \(\textit{N}\) (\(\textit{N}\) is the ratio of electromagnetic to inertial forces). The main objective of this paper is to provide the scientific and engineering community with common references to assist fusion researchers in the selection of adequate computational means to be used for blanket design and analysis. As an initial validation case, the two codes are applied to the classic problem of a laminar fully developed MHD flows in a rectangular duct. Both codes demonstrate a very good agreement with the analytical solution for \(\textit{Ha}\) up to 15, 000. To address the capabilities of the two codes to properly resolve complex geometry flows, we consider a case of three-dimensional developing MHD flow in a geometry comprising of a series of interconnected electrically conducting rectangular ducts. The computed electric potential distributions for two flows (Case A) \(\textit{Ha}=515\), \(\textit{N}=3.2\) and (Case B) \(\textit{Ha}=2059\), \(\textit{N}=63.8\) are in very good agreement with the experimental data, while the comparisons for the MHD pressure drop are still unsatisfactory. To better interpret the observed differences, the obtained numerical data are analyzed against earlier theoretical and experimental studies for flows that involve changes in the relative orientation between the flow and the magnetic field. 相似文献
984.
Alina Climova Ekaterina Pivovarova Bartomiej Rogalewicz Anita Raducka Magorzata Szczesio Izabela Korona-Gowniak Agnieszka Korga-Plewko Magdalena Iwan Katarzyna Gobis Agnieszka Czylkowska 《Molecules (Basel, Switzerland)》2022,27(11)
New coordination compounds of Mn(II), Fe(III), Co(II), and Ni(II) and the biologically active ligand L (N′-benzylidenepyrazine-2-carbohydrazonamide) were synthesized and characterized by appropriate analytical techniques: elemental analysis (EA), thermogravimetric analysis (TG–DTG), infrared spectroscopy (FTIR), and flame-atomic absorption spectrometry (F-AAS). The biological activity of the obtained compounds was then comprehensively investigated. Rational use of these compounds as potential drugs was proven by ADME analysis. All obtained compounds were screened in vitro for antibacterial, antifungal, and anticancer activities. Some of the studied complexes exhibited significantly higher activity than the ligand alone. 相似文献
985.
Guo Nan Yin Do-Kyun Kim Ji In Kang Yebin Im Dong Sun Lee Ah-reum Han Jiyeon Ock Min-Ji Choi Mi-Hye Kwon Anita Limanjaya Saet-Byel Jung Jimin Yang Kwang Wook Min Jeongwon Yun Yongjun Koh Jong-Eun Park Daehee Hwang Jun-Kyu Suh Ji-Kan Ryu Ho Min Kim 《Experimental & molecular medicine》2022,54(5):626
Diabetes mellitus (DM) is a chronic metabolic disorder characterized by inappropriate hyperglycemia, which causes endothelial dysfunction and peripheral neuropathy, ultimately leading to multiple complications. One prevalent complication is diabetic erectile dysfunction (ED), which is more severe and more resistant to treatment than nondiabetic ED. The serum glycoprotein leucine-rich ɑ-2-glycoprotein 1 (LRG1) is a modulator of TGF-β-mediated angiogenesis and has been proposed as a biomarker for a variety of diseases, including DM. Here, we found that the adhesion GPCR latrophilin-2 (LPHN2) is a TGF-β-independent receptor of LRG1. By interacting with LPHN2, LRG1 promotes both angiogenic and neurotrophic processes in mouse tissue explants under hyperglycemic conditions. Preclinical studies in a diabetic ED mouse model showed that LRG1 administration into the penile tissue, which exhibits significantly increased LPHN2 expression, fully restores erectile function by rescuing vascular and neurological abnormalities. Further investigations revealed that PI3K, AKT, and NF-κB p65 constitute the key intracellular signaling pathway of the LRG1/LPHN2 axis, providing important mechanistic insights into LRG1-mediated angiogenesis and nerve regeneration in DM. Our findings suggest that LRG1 can be a potential new therapeutic option for treating aberrant peripheral blood vessels and neuropathy associated with diabetic complications, such as diabetic ED.Subject terms: Biological therapy, Cytokines, Recombinant protein therapy, Extracellular signalling molecules 相似文献
986.
Dr. Shiyong Chu Prof. Duho Kim Gwanghyeon Choi Chunchen Zhang Haoyu Li Prof. Wei Kong Pang Yameng Fan Anita M. D'Angelo Prof. Shaohua Guo Prof. Haoshen Zhou 《Angewandte Chemie (International ed. in English)》2023,62(12):e202216174
Cation migration often occurs in layered oxide cathodes of lithium-ion batteries due to the similar ion radius of Li and transition metals (TMs). Although Na and TM show a big difference of ion radius, TMs in layered cathodes of sodium-ion batteries (SIBs) can still migrate to Na layer, leading to serious electrochemical degeneration. To elucidate the origin of TM migration in layered SIB cathodes, we choose NaCrO2, a typical layered cathode suffering from serious TM migration, as a model material and find that the TM migration is derived from the random desodiation and subsequent formation of Na-free layer at high charge potential. A Ru/Ti co-doping strategy is developed to address the issue, where the doped active Ru is first oxidized to create a selective desodiation and the doped inactive Ti can function as a pillar to avoid complete desodiation in Ru-contained TM layers, leading to the suppression of the Na-free layer formation and subsequent enhanced electrochemical performance. 相似文献
987.
988.
Paul Ebensperger Mariia Zmyslia Philipp Lohner Judith Braunreuther Benedikt Deuringer Anita Becherer Regine Süss Anna Fischer Claudia Jessen-Trefzer 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218413
Herein, we describe the creation of an artificial protein cage housing a dual-metal-tagged guest protein that catalyzes a linear, two-step sequential cascade reaction. The guest protein consists of a fusion protein of HaloTag and monomeric rhizavidin. Inside the protein capsid, we established a ruthenium-catalyzed allylcarbamate deprotection reaction followed by a gold-catalyzed ring-closing hydroamination reaction that led to indoles and phenanthridines with an overall yield of up to 66 % in aqueous solutions. Furthermore, we show that the encapsulation stabilizes the metal catalysts against deactivation by air, proteins and cell lysate. 相似文献
989.
Levi Matteo Martini Alessio Santagati Federico Tabacco Anita Vallarino Maria 《Journal of Fourier Analysis and Applications》2023,29(2):1-37
Journal of Fourier Analysis and Applications - We introduce and study the notion of weak semi-greedy systems—which is inspired in the concepts of semi-greedy and branch semi-greedy systems... 相似文献
990.