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Automatic Detection of Galaxy Clusters Applying Cluster Red Sequence Algorithm: Galaxy Clusters and Groups in the Field of the Survey
, M.Sc. Thesis Sharif University of Technology ; Mansouri, Reza (Supervisor)
Abstract
Galaxy clusters are the most massive virialized systems in the universe. Their studies provide crucial grasp on the galaxy formation and evolution, dark matter and its nature, cosmological parameters and large scale structure of the universe. Because of their significant role in cosmology, providing a catalogue of galaxy clusters in a wide range of spatial angle, mass and redshift seems vital. Galaxy cluster detection can be performed by various methods in a broad spectrum of electromagnetic radiation. Optical detection of galaxy clusters is of the most traditional and popular methods. Among optical algorithms, one of the most efficient is called Cluster Red Sequence (CRS) which applies the...
Investigation of optical detection strategies for transabdominal fetal heart rate detection using three-layered tissue model and Monte Carlo simulation
, Article Optica Applicata ; Volume 41, Issue 4 , 2011 , Pages 885-896 ; 00785466 (ISSN) ; Zahedi, E ; Mohd Ali, M. A ; Sharif University of Technology
Abstract
In this paper, the Monte Carlo technique is used to determine the optical detection strategies in three-layered (maternal, amniotic fluid and fetal) tissue model. This model is utilized to estimate the transabdominal optical power and optimum source-detector (S-D) separation. Results based on the launching of 2 million photons with 1 mW optical power showed that the expected optical power output is in the range of 10 -6-10 -10 W/cm 2 depending on S-D separation. Considering the limit of the signal processing methods (such as adaptive noise cancelling) and the use of silicon photodetector, an S-D separation of 4 cm has been selected as a practical compromise between signal level and...
Optical detection of phenolic compounds based on the surface plasmon resonance band of Au nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 71, Issue 1 , 2008 , Pages 199-203 ; 13861425 (ISSN) ; Alimohammadi, M ; Tashkhourian, J ; Razavian, S. M ; Sharif University of Technology
2008
Abstract
An indirect colorimetric method is presented for detection of trace amounts of hydroquinone (1), catechol (2) and pyrogallol (3). The reduction of AuCl4- to Gold nanoparticles (Au-NPs) by these phenolic compounds in the presence of cetyltrimethylammonium chloride (CTAC) produced very intense surface plasmon resonance peak of Au-NPs. The plasmon absorbance of Au-NPs allows the quantitative colorimetric detection of the phenolic compounds. The calibration curves derived from the changes in absorbance at λ = 568 nm were linear with concentration of hydroquinone, catechol and pyrogallol in the range of 7.0 × 10-7 to 1.0 × 10-4M, 6.0 × 10-6 to 2.0 × 10-4 M and 6.0 × 10-7 to 1.0 × 10-4 M,...
Bioactive hybrid metal-organic framework (MOF)-based nanosensors for optical detection of recombinant SARS-CoV-2 spike antigen
, Article Science of the Total Environment ; Volume 825 , 2022 ; 00489697 (ISSN) ; Fatahi, Y ; Ahmadi, S ; Abbariki, N ; Ojaghi, A ; Rabiee, M ; Radmanesh, F ; Dinarvand, R ; Bagherzadeh, M ; Mostafavi, E ; Ashrafizadeh, M ; Makvandi, P ; Lima, E. C ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Fast, efficient, and accurate detection of SARS-CoV-2 spike antigen is pivotal to control the spread and reduce the mortality of COVID-19. Nevertheless, the sensitivity of available nanobiosensors to detect recombinant SARS-CoV-2 spike antigen seems insufficient. As a proof-of-concept, MOF-5/CoNi2S4 is developed as a low-cost, safe, and bioactive hybrid nanostructure via the one-pot high-gravity protocol. Then, the porphyrin, H2TMP, was attached to the surface of the synthesized nanomaterial to increase the porosity for efficient detection of recombinant SARS-CoV-2 spike antigen. AFM results approved roughness in different ranges, including 0.54 to 0.74 μm and 0.78 to ≈0.80 μm, showing good...