Fiducial marker

Depending on excitation wavelength either of two emission spectra may be observed (Fig. 3). The twin peaks at 690.5 nm and 692.2 nm represent long lived emission resulting from excitation of the sapphire matrix plate and are useful fiducial markers. 

Raman spectra were recorded on a J-Y Ramanor spectrometer, using an argon ion laser (488.0 nm) excitation, for several compositions of C Fi (HF). The spectral resolution was 2 cm. Typically, 100 scans were taken and added together from powder samples that were contained in quartz X-ray capillaries the quartz line at 808 cm provided a fiducial marker in the spectra. 

In the early days of radioisotope scanning, scans were always superimposed over radiographs taken at the same time in the nuclear medicine department. Fiducial markers were used to superimpose anatomy and radionuclide distributions accurately. 

Registration basis. Refers to the image features that will be used to establish the alignment. These can be extrinsic registration objects, such as a stereotactic frame or fiducial markers, or intrinsic, such as anatomical landmarks, anatomical contours, or pixel intensity values. 

Tensho K, Kodaira H, Yasuda G, Yoshimura Y, Narita N, Morioka S, Kato H, Saito N (2011) Anatomic double-bundle anterior cmciate ligament reconstruction, using CT-based navigation and fiducial markers. Knee Surg Sports Traumatol Arthrosc 19 378-383. doi 10.1007/s00167-010-1217-y... 

Susil RC, Menard C, Krieger A et al (2006) Transrectal prostate biopsy and fiducial marker placement in a standard 1.5 T magnetic resonance imaging scanner. J Urol 175 113-120... 

Ferreira CR, Wu L, Vogt G, et al. Fiducial markers for distribution of drug and excipient on tablet surfaces by multimodel desorption eleetrospray ionization-mass spectrometry (DESI-MS) imaging. Anal Lett. 2014 47 91-101. 

Figura 3. Vacuum cleaner with fiducial markers AR. (Goncalves, 2012).

In the third research, Gonsalves (2012) proposed the use of Augmented Reality, through the use of serious game , for the guidance of the use of a new product (electric appliance). For both, virtual objects and sound instructions were generated from fiducial markers (Figure 3). 

While the studies discussed so far were concerned with the sintering of metals, the question of material transport in sintering is as pertinent for ionic solids as it is for metals. At the temperatures where sintering is important extensive plastic deformation by dislocation motion is possible in both single crystals and polycrystalline aggregates of ionic solids. It was therefore decided to adapt the Brett and Seigle technique of sintering with fiducial markers to an ionic crystalline solid, calcium fluoride. 

A last important point is drift correction (reeNote 6). The high localization accuracy, together with the relatively long imaging time, makes SMLM vulnerable for drift of the sample with respect to the objective during image acquisition. Sample drift causes incorrect fluorophores localizations and should be corrected for. There are in general two ways to correct sample drift. Firstly, drift can be monitored from frame to frame with the use of fiducial markers. 

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