scholarly journals Atmospheric Neutron Monitoring through Optical Fiber-Based Sensing

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4510 ◽  
Author(s):  
Sylvain Girard ◽  
Adriana Morana ◽  
Cornelia Hoehr ◽  
Michael Trinczek ◽  
Jeoffray Vidalot ◽  
...  
Keyword(s):  
New York ◽  
Optical Fiber ◽  
Outer Space ◽  
Sensitivity Coefficient ◽  
Radiation Sensitivity ◽  
Future Application ◽  
Reference Spectrum ◽  
X Rays ◽  
Neutron Exposure ◽  
Balloon Experiments

The potential of fiber-based sensors to monitor the fluence of atmospheric neutrons is evaluated through accelerated tests at the TRIUMF Neutron Facility (TNF) (BC, Canada), offering a flux approximatively 109 higher than the reference spectrum observed under standard conditions in New York City, USA. The radiation-induced attenuation (RIA) at 1625 nm of a phosphorus-doped radiation sensitive optical fiber is shown to linearly increase with neutron fluence, allowing an in situ and easy monitoring of the neutron flux and fluence at this facility. Furthermore, our experiments show that the fiber response remains sensitive to the ionization processes, at least up to a fluence of 7.1 × 1011 n cm−², as its radiation sensitivity coefficient (~3.36 dB km−1 Gy−1) under neutron exposure remains very similar to the one measured under X-rays (~3.8 dB km−1 Gy−1) at the same wavelength. The presented results open the way to the development of a point-like or even a distributed dosimeter for natural or man-made neutron-rich environments. The feasibility to measure the dose caused by the neutron exposure during stratospheric balloon experiments, or during outer space missions, is presented as a case study of a potential future application.

EU Draft Code of Conduct for Outer Space Activities

2021 ◽  
pp. 153-159
Keyword(s):  
New York ◽  
Space Debris ◽  
Outer Space ◽  
Code Of Conduct ◽  
The European Union ◽  
Draft Code ◽  
The Subject ◽  
Asian Pacific ◽  
Space Activities ◽  
The Eu

This chapter describes the main contents of the European Union (EU) Draft Code of Conduct for Outer Space Activities, Space Debris and Liability Convention. It is necessary and desirable for us to legislate more concretely the abovementioned draft Code of Conduct for Outer Space Activities so as to mitigate or remove space debris. In December 2008, the EU adopted a Draft Code of Conduct (EU Draft CoC) for outer space activities. On September 2010, the EU revised a second draft of the EU Code of Conduct for Outer Space Activities. The draft of the International Code of Conduct (the Code), dated March 31, 2014, was intended to be the subject of negotiations at the United Nations in New York from July 27-31, 2015. The code, a politically and not legally binding document, aims to establish some rules of good conduct for outer space activities. The author proposes the establishment of a new Asian-Pacific International and Environmental Monitoring Organization (tentative title) for prevention and mitigation of space debris.

scholarly journals Sublethal Radiation Affects Antigen Processing and Presentation Genes to Enhance Immunogenicity of Cancer Cells

2020 ◽  
Vol 21 (7) ◽  
pp. 2573 ◽  
Author(s):  
Achamaporn Punnanitinont ◽  
Eric D. Kannisto ◽  
Junko Matsuzaki ◽  
Kunle Odunsi ◽  
Sai Yendamuri ◽  
...  
Keyword(s):  
New York ◽  
T Cells ◽  
Cancer Cells ◽  
Cell Lines ◽  
Antigen Processing ◽  
Tumor Antigens ◽  
T Cell Response ◽  
Live Cells ◽  
X Rays ◽  
Antigen Processing And Presentation

While immunotherapy in cancer is designed to stimulate effector T cell response, tumor-associated antigens have to be presented on malignant cells at a sufficient level for recognition of cancer by T cells. Recent studies suggest that radiotherapy enhances the anti-cancer immune response and also improves the efficacy of immunotherapy. To understand the molecular basis of such observations, we examined the effect of ionizing X-rays on tumor antigens and their presentation in a set of nine human cell lines representing cancers of the esophagus, lung, and head and neck. A single dose of 7.5 or 15 Gy radiation enhanced the New York esophageal squamous cell carcinoma 1 (NY-ESO-1) tumor-antigen-mediated recognition of cancer cells by NY-ESO-1-specific CD8+ T cells. Irradiation led to significant enlargement of live cells after four days, and microscopy and flow cytometry revealed multinucleation and polyploidy in the cells because of dysregulated mitosis, which was also revealed in RNA-sequencing-based transcriptome profiles of cells. Transcriptome analyses also showed that while radiation had no universal effect on genes encoding tumor antigens, it upregulated the expression of numerous genes involved in antigen processing and presentation pathways in all cell lines. This effect may explain the immunostimulatory role of cancer radiotherapy.

scholarly journals Polydopamine-Assisted Fabrication of Stable Silver Nanoparticles on Optical Fiber for Enhanced Plasmonic Sensing

2019 ◽  
Vol 10 (2) ◽  
pp. 97-104 ◽  
Author(s):  
Yiwen Tang ◽  
Hui Yuan ◽  
Jiangping Chen ◽  
Qiguo Xing ◽  
Rongxin Su ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Localized Surface Plasmon Resonance ◽  
Optical Fiber Sensor ◽  
Redox Activity ◽  
Fiber Sensor ◽  
Localized Surface Plasmon ◽  
Future Application ◽  
Ag Nps ◽  
Plasmonic Sensing

Abstract We present a facile and effective method for fabrication of the localized surface plasmon resonance (LSPR) optical fiber sensor assisted by two polydopamine (PDA) layers with enhanced plasmonic sensing performance. The first PDA layer was self-polymerized onto the bare optical fiber to provide the catechol groups for the reduction from Ag+ to Ago through chelating and redox activity. As the reduction of Ag+ proceeds, Ag nanoparticles (NPs) were grown in-situ on the PDA layer with uniform distribution. The second PDA layer was applied to prevent Ag NPs from oxidating and achieve an improvement of LSPR signal. The PDA/Ag/PDA-based optical fiber sensor has an enhanced LSPR sensitivity of 961 nm/RIU and excellent oxidation resistance. The stable PDA/Ag/PDA-based LSPR sensor with high optical performance is very promising for future application in optical sensing field.

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