scholarly journals Design of a Start-Up Sequence Controller for a Mammography Machine

2021 ◽  
Vol 23 (06) ◽  
pp. 537-545
Author(s):  
Rakshak Udupa T S ◽  
◽  
Shashank K Holla ◽  
Namita Palecha ◽  
◽  
...  
Keyword(s):  
Low Energy ◽  
X Rays ◽  
Human Breast ◽  
Cell Width ◽  
Start Up ◽  
Temperature Reading ◽  
A Cell ◽  
Temperature And Pressure ◽  
Scan Chain ◽  
Detect Breast Cancer

Mammography, which is also calledMastography, is the process of using low-energy X-rays to inspect the human breast for screening and diagnostics. The purpose of mammography is to detect breast cancer early, usually by looking for specific lumps or microcalcifications. The X-rays used are usually around 30 kVp. Excessive voltage to such a machine would be harmful to the patient. Proper monitoring of temperature and pressure needs to be ensured. To ensure this, a start-up sequence module is developed. The start-up sequence module reads the digitized voltage, pressure, and temperature reading from the sensor and asserts all the outputs to ensure that the machine is ready. The scan chain is formed of 13 scan flip-flops in this configuration. The synthesis mapped the design to 484 instances of cells in the open-source PDK technology. The design had a total area of 594 μm2, with a cell width of 0.297 μm, and a height of 0.99 μm.

Preincubation with Sn-complexes causes intensive intracellular retention of 99mTc in thyroid cells in vitro

2012 ◽  
Vol 51 (05) ◽  
pp. 179-185 ◽  
Author(s):  
M. Wendisch ◽  
D. Aurich ◽  
R. Runge ◽  
R. Freudenberg ◽  
J. Kotzerke ◽  
...  
Keyword(s):  
Cell Model ◽  
Low Energy ◽  
Thyroid Cells ◽  
Low Energy Electrons ◽  
A Cell ◽  
Vitro Model ◽  
Uptake Studies ◽  
Radiobiological Effects ◽  
Radioactivity Retention

SummaryTechnetium radiopharmaceuticals are well established in nuclear medicine. Besides its well-known gamma radiation, 99mTc emits an average of five Auger and internal conversion electrons per decay. The biological toxicity of these low-energy, high-LET (linear energy transfer) emissions is a controversial subject. One aim of this study was to estimate in a cell model how much 99mTc can be present in exposed cells and which radiobiological effects could be estimated in 99mTc-overloaded cells. Methods: Sodium iodine symporter (NIS)- positive thyroid cells were used. 99mTc-uptake studies were performed after preincubation with a non-radioactive (cold) stannous pyro - phosphate kit solution or as a standard 99mTc pyrophosphate kit preparation or with pure pertechnetate solution. Survival curves were analyzed from colony-forming assays. Results: Preincubation with stannous complexes causes irreversible intracellular radioactivity retention of 99mTc and is followed by further pertechnetate influx to an unexpectedly high 99mTc level. The uptake of 99mTc pertechnetate in NIS-positive cells can be modified using stannous pyrophosphate from 3–5% to >80%. The maximum possible cellular uptake of 99mTc was 90 Bq/cell. Compared with nearly pure extracellular irradiation from routine 99mTc complexes, cell survival was reduced by 3–4 orders of magnitude after preincubation with stannous pyrophosphate. Conclusions: Intra cellular 99mTc retention is related to reduced survival, which is most likely mediated by the emission of low-energy electrons. Our findings show that the described experiments constitute a simple and useful in vitro model for radiobiological investigations in a cell model.

Key comparison BIPM.RI(I)-K2 of the air-kerma standards of the LNE–LNHB, France and the BIPM in low-energy x-rays

Metrologia ◽  
2011 ◽  
Vol 48 (1A) ◽  
pp. 06013-06013 ◽  
Author(s):  
D T Burns ◽  
P Roger ◽  
M Denozière ◽  
E Leroy
Keyword(s):  
Low Energy ◽  
X Rays ◽  
Key Comparison ◽  
Air Kerma

Dark-Field X-Ray Microscopy of Immunogold-Labeled Cells

1996 ◽  
Vol 2 (2) ◽  
pp. 53-62 ◽  
Author(s):  
Henry N. Chapman ◽  
Jenny Fu ◽  
Chris Jacobsen ◽  
Shawn Williams
Keyword(s):  
Colloidal Gold ◽  
Dark Field Image ◽  
Dark Field ◽  
X Rays ◽  
X Ray ◽  
Scanning Transmission ◽  
A Cell ◽  
Specific Antigens ◽  
Genetic Sequences ◽  
Novel Method

The methods of immunolabeling make visible the presence of specific antigens, proteins, genetic sequences, or functions of a cell. In this paper we present examples of imaging immunolabels in a scanning transmission x-ray microscope using the novel method of dark-field contrast. Colloidal gold, or silver-enhanced colloidal gold, is used as a label, which strongly scatters x-rays. This leads to a high-contrast dark-field image of the label and reduced radiation dose to the specimen. The x-ray images are compared with electron micrographs of the same labeled, unsectioned, whole cell. It is verified that the dark-field x-ray signal is primarily due to the label and the bright-field x-ray signal, showing absorption due to carbon, is largely unaffected by the label. The label can be well visualized even when it is embedded in or laying behind dense material, such as the cell nucleus. The resolution of the images is measured to be 60 nm, without the need for computer processing. This figure includes the x-ray microscope resolution and the accuracy of the label positioning. The technique should be particularly useful for the study of relatively thick (up to 10 μm), wet, or frozen hydrated specimens.

The Relative Biological Effectiveness of Low-Dose Mammography Quality X Rays in the Human Breast MCF-10A Cell Line

2015 ◽  
Vol 183 (1) ◽  
pp. 42-51 ◽  
Author(s):  
Caitlin E. Mills ◽  
Christopher Thome ◽  
David Koff ◽  
David W. Andrews ◽  
Douglas R. Boreham
Keyword(s):  
Cell Line ◽  
Low Dose ◽  
Relative Biological Effectiveness ◽  
X Rays ◽  
Human Breast ◽  
Biological Effectiveness

scholarly journals The use of fricke dosimetry for low energy x-rays

2006 ◽  
Vol 49 (spe) ◽  
pp. 17-23 ◽  
Author(s):  
Carlos de Austerlitz ◽  
Viviane Souza ◽  
Heldio Pereira Villar ◽  
Aloisio Cordilha
Keyword(s):  
Ionization Chamber ◽  
Parallel Plate ◽  
Low Energy ◽  
Calibration Factor ◽  
X Rays ◽  
Measuring Systems ◽  
X Ray ◽  
Dose Measurements

The performance of four X-ray qualities generated in a Pantak X-ray machine operating at 30-100 kV was determined with a parallel-plate ionization chamber and a Fricke dosimeter. X-ray qualities used were those recommended by Deutsch Internationale Normung DIN 6809 and dose measurements were carried out with Plexiglas® simulators. Results have shown that the Fricke dosimeter can be used not only for soft X-ray dosimetry, but also for the maintenance of low-energy measuring systems' calibration factor.

Investigation of gas generation in regenerative fuel cells by low-energy X-rays

2015 ◽  
Vol 296 ◽  
pp. 133-141 ◽  
Author(s):  
Omer Faruk Selamet ◽  
Phengxay Deevanhxay ◽  
Shohji Tsushima ◽  
Shuichiro Hirai
Keyword(s):  
Fuel Cells ◽  
Low Energy ◽  
X Rays ◽  
Gas Generation
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