Make figures and presentations that are pleasant to Colorblind other folks (2002)

Coloration In style Invent (CUD)

– fabricate figures and presentations that are pleasant to Colorblind other folks –

Masataka Okabe

Jikei Medial College (Japan)

University of Tokyo, Institute for Molecular and Cell Biosciences (Japan)


(both are exact protanopes)

11.20.2002 (modified on 2.15.2008, 9.24.2008)

NEW: Adobe Photoshop/Illustrator with colorblind proof efficiency launched.

Index

1. What is colorblind?
   
2. How colorblind other folks scrutinize colors?
   
3. Figures of fluorescent staining (microscope images and DNA chip)
   
4. remodel red to magenta
   
5. Single-channel photographs
   
6. Three-channel photographs
   When assigning colors to drawings
   
7. “redundant coding”
   
8. Example of redundantly coded drawings
   
9. grab colors that are more uncomplicated to distinguish
   
10. Space of colors that is unambiguous both to colorblinds and non-colorblinds
    
11. Steer clear of indicating objects handiest by names
    
12. Inexperienced laser pointer
    
13. Colorblind proofing (checker) tool and hardware
    
14. Display: When the negate of colorblind proofing systems (indispensable!)
    
15. Coloration In style Invent Group
    
16. PDF and PowerPoint recordsdata for brochure and presentation

Colorblindness is now not a total lack of color vision. Colorblind other folks can acknowledge a large ranges of colors. But certain ranges of colors are exhausting to distinguish.

The frequency of colorblindness is reasonably excessive. One in twelve Caucasian (8%), one in 20 Asian (5%), and one in 25 African (4%) males are so-known as “red-green” colorblind. It’s miles commoner than AB blood community.

There are frequently colorblind other folks among the many viewers and readers. There must be more than TEN colorblinds in a room with 250 other folks. While you diagram a facility or industrial product that will be standard by 10,000 other folks, 400 of them would be colorblinds. (assuming 50% male and 50% female.)

When making ready your presentations (papers, slides, documents, ads, online pages and so on.) as neatly as public services and industrial merchandise, please grasp this into story. Listed right here are some comments on how one can fabricate figures and presentations colorblind pleasant.

3(+1) rules of Coloration In style Invent

For scientists:


There would possibly perhaps be a lawful likelihood that the paper you put up would possibly perhaps presumably additionally simply match to colorblind reviewers. Supposing that your paper will be reviewed by three white males (which is now not unlikely thinking in regards to the recent inhabitants in science), the likelihood that as a minimal one among them is colorblind is whopping 22%!


[ 22% = 1-(1-0.92)^3 ]

What is colorblind?

The human look for has three sorts of cone cells. These cells speak numerous sorts of opsin genes, that are sensitive essentially to red, green and blue, respectively. Colorblindness is the deliver where the feature of 1 in all those opsins are misplaced, or perturbed.

Fig 1 Structure of the quest for

Individuals sense colors by evaluating the output of three sorts of cone cells. Here is named trichromacy . The sensitivity spectrum of the red, green and blue cone cells overlap greatly, though. (Look high left panel beneath.)

If the feature of 1 style of the cones cells is misplaced, the person can quiet acknowledge reasonably lawful diversity of hues the negate of the final two cone cell sorts. But certain fluctuate of colors, as an instance between red and green, turns into more troublesome to distinguish. Here is named dichromacy . (The final five panels.)

If the spectrum of a particular cone cell kind is shifted, infrequently which potential of the mutation in a opsin gene, color vision turns into reasonably an identical to the dichromatic person. Here is named anomalous trichromacy . The extent how color vision is affected is dependent upon where the mutation occurred within the gene. The color vision of some anomalous trichromacy other folks is as affected as a dichromacy other folks. Some are nearly much like non-colorblind.

The bulk of colorblind is the so known as “red-green colorblind,” with complications both within the red or green opsin gene. Individuals with mutant red opsin gene is named protanope , and green opsin gene deuteranope .

Individuals with the deliver in blue opsin gene is named tritanope . Here is somewhat uncommon, with handiest 0.001% of incidence.

Fig 2 Forms of colorblindness (with frequency among Caucasoid male)

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How colorblind other folks scrutinize colors ?

Fig 3 Simulation of colorblind vision

Coloration vision of the red-green colorblind (protanopes and deuteranopes)

• Sophisticated to distinguish colors between red and green with an identical intensity (brightness). The confusion occurs in reasonably symmetric manner: The diversifications between “green and red” and “yellow green and yellow” is amazingly puny.
• As well, protanopes in actuality feel “red” considerable darker, for the reason that cone cells that duvet the longest fluctuate of wavelengths are defect. Thus, “sad red” seem nearly as “shaded.”
• On the replace, deuteranopes have not any deliver seeing “green” even if their green cone cells are defect. Here is for this reason fluctuate of wavelengths is additionally covered sufficiently by the blue and red cone cells.
  
  

Fig 4 Mixture of colors that are confusing for red-green colorblinds

• Sophisticated to distinguish certain colors which fluctuate handiest in their red or green ingredient. For instance, “blue and violet (blue+red)”, “green and brown”, and “red and brown.”
• In contrast to intellectual colors (with higher saturation), low saturation colors are especially exhausting to distinguish. For instance, “sky blue and pink”, “grey, faded sky blue and faded green”, and so on.
• To compensate the lack of red or green cone cells, colorblind other folks rely more on the guidelines from the blue cone cells. Thus, they are usually more sensitive to distinguish bluish hues than the non-colorblind other folks. For instance,colorblind other folks judge “red and green” or “yellow and yellow green” are nearly the same color. But they regard “green and bluish green (emerald)” as entirely numerous colors. (Evaluate the rectangles within the forth row of the above figure.)
• To compensate the low resolution within the recognition of hues, colorblind other folks are usually more sensitive to the variations in brightness and saturation.

• Coloration names are given to the categories of colors that seem an identical to non-colorblind other folks. This categorization would possibly perhaps presumably additionally simply now not be neatly matched with the color vision of the colorblind other folks. Thus, communication the negate of color names are infrequently very sophisticated.
  
  Example 1 : Diversified names for the same color -> Third and Fourth rows of the above figure. These colors all seem “brown” to colorblinds. But non-colorblinds set varied names equivalent to green, red, orange and brown. Colorblinds can now not divulge which is which.
  
  Example 2 :Related color name for numerous colors -> Fifth and Sixth rows of the above figure. Even though Inexperienced and Bluish green are labeled as “an identical color” by non-colorblinds, colorblinds judge they are fully numerous colors, rather more so than between red and green.
  
  
  These variations change into the motive of miscommunication.

Coloration vision of the blue-yellow colorblind (tritanopes)

• Even though human has three sorts of cone cells, non colorblinds carefully rely on the guidelines from red and green cells to distinguish colors. Contribution of recordsdata from the blue cone cells is somewhat low. Thus, even supposing tritanopes lacks the blue cone cells, their color vision is more an identical to non-colorblinds than protanopes and deuteranopes. The honor between blue and green, nonetheless, is more sophisticated than the non-colorblinds.

Coloration vision of the entire colorblind

• If two sorts of cone cells are defect, the person loses color vision. Here is rarer than the blue-yellow colorblind. Severe lack of eyesight additionally occurs.

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———-


The following few sections would possibly perhaps presumably additionally simply now not be intriguing for those that must now not biological scientists. Please skip to: When assigning colors to drawings.


———-

Figures of fluorescent staining (microscope images and DNA chip)

The ultimate deliver for the colorblind scientists (especially biologists) would be getting recordsdata from the fluorescent images.

With as of late’s digital imaging machine equivalent to confocal microscopes, CCD cameras and array imagers, it’s a ways amazingly easy to swap the colors of every recording channel. When making ready for presentation, there is now not any reason to stay with the color you before the entire thing standard for staining. Please grasp the combo of colors that is most comprehensible to the viewers.

two-channel photographs

Fluorescent double staining and DNA chips infrequently negate red and green to divulge every channel. This causes two complications for colorblinds.

1: Very unlikely to impress which segment is labeled with green and which segment with red.

Fig 5 A conventional fluorescent micrograph.

Fig 6 Simulation of how colorblinds scrutinize this describe.

2: Very unlikely to distinguish the sphere of “double certain.” For colorblind other folks, yellow (red plus green) appears much like vivid green.

Fig 7 Above: Staining of two cells with labeled with one and two colors. Under: DNA chip with two colors.

resolve this deliver?

Please negate magenta (purple) as a replace of red. Magenta is the equal mixture of red and blue. Even though colorblind other folks own topic recognizing the red ingredient, they’ll without misfortune acknowledge the blue hue. The sphere of double certain turns into white , which is without misfortune distinguishable for colorblinds.

Fig 8 Red-green (above) and magenta-green (beneath) model of the same photographs.

remodel red to magenta

The conversion is amazingly easy. Comely reproduction the image of red channel to blue channel the negate of image-manipuration tool equivalent to Adobe photoshop.

Fig 9 Conversion from red to magenta

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Single-channel photographs

Even images with single staining motive deliver for colorblinds. Many of us recent such photographs with the color of the fluorescent dye standard for the staining. But there are again two complications:

1: The images in pure red is hardly visible for the protanopes (scrutinize beneath for simulation). Even non-colorblind other folks in actuality feel topic seeing blue images.

Fig 10 protanope simulation of single staining in green and red

2: Pure green and red are out of gamut (printable color fluctuate). Refined gradation will be misplaced within the published paper. For instance, vivid greens must now not printable. They’re all converted to customary sad greens when printed, shedding the guidelines about signal intensity.

Fig. 11 Photos with pure colors on mask (left) and when printed (pretty)

Thus, monochrome is the handiest for tonal reproduction. Can you bring more recordsdata by making it color? While you just want to divulge what more or much less label you weird and wonderful (GFP, Cy3, and so on.), a sentence within the figure legend would possibly perhaps presumably additionally simply be ample.

Fig. 12 grayscale image

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Three-channel photographs

In case of staining with three labels,

1: Showcase grayscale photographs of every channel. (when distribution of every signal is intriguing)

2: Showcase combos of two channels in magenta and green. (when spatial correlation between channels is intriguing)

Fig. 13 triple staining

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When assigning colors to drawings

“redundant coding”

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Example of redundantly coded drawings

Fig. 14?Line drawings

Whereas the left graph negate handiest color for coding, the left graph uses both color and shapes to distinguish numerous traces.

1. Thicker traces and greater symbols fabricate it more uncomplicated to distinguish colors. (Extra cone cells would possibly perhaps presumably be standard for color detection.)
2. Lines own numerous shapes (exact and dotted) so as that they stumble on numerous even without color.
3. Diversified symbols are standard for every positive aspects (circles, triangles and squares.)
4. Separate keys are shunned. Labels are shown straight within the center of the drawings, connected with skinny traces. This style there is now not any must evaluation the colors of two a ways away objects (traces and their keys). Here is infrequently sophisticated for colorblinds even when the objects are handiest about a centimeters apart.
5. Thus, the improved drawing can bring ample recordsdata even without color. For instance, this drawing would now not lose any recordsdata when being faxed or copied in shaded and white.

The discontinuance graph is coded handiest by colors. Since faded and unsaturated colors are chosen, it’s a ways sophisticated to distinguish numerous colors It’s miles additionally sophisticated to deliver the name of every color, making it sophisticated for communication. Readers are asked to evaluation the color of the graph itself with the separate keys. Here is amazingly sophisticated for Colorblinds.

The 2nd graph is a cramped bit higher. The colors are more intellectual and more uncomplicated to call. Separate keys are shunned so as that readers now not must evaluation the colors of a ways away objects.

The underside graph is the handiest. It uses now not handiest colors but additionally varied hatching. Every object is clearly distinguishable even without color vision. Yet again, this drawing would now not lose any recordsdata when being faxed or copied.

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grab colors that are more uncomplicated to distinguish.

Here is relevant handiest AFTER you designed the figure with redundant coding. (Look above)

Being pleasant to colorblind other folks would now not necessarily suggest that one must never negate colors. Even for the colorblinds, colors are very priceless cues to distinguish numerous objects without misfortune and quick. By carefully deciding on colors that are without misfortune recognizable to other folks with every style of color vision, one can maximize the stay of her/his presentations.

1) Steer clear of the deliver where indispensable recordsdata is conveyed handiest within the come by of color.

2) Steer clear of the deliver where texts and objects are obscured with the background.

For instance, there must be ample contrasts in brightness and saturation between texts/objects and backgrounds. Steer clear of the combo of colors which own the same brightness but numerous handiest in hue. For instance, red characters on green backgrounds is unreadable for colorblinds. Exhaust both vivid texts/objects over sad backgrounds, or vice versa.

3) Make texts and objects as thick or abundant as that you just would possibly perhaps additionally judge of.

When the dimension of color-coded objects is puny, handiest about a cone cells would possibly perhaps presumably be standard for recognition. Colorblind other folks receive it especially sophisticated to distinguish the colors of thin traces and puny symbols. For color-coded textual direct material, negate courageous fonts equivalent to Arial or Helvetica , moderately than skinny Events or NewYork .

4) Warning when the negate of red.

For non-colorblind other folks, red is the intense and intellectual color. But for colorblinds, it’s a ways as tiresome as blue or sad green. Especially for protanopes, who can now not detect lengthy wavelength of red gentle, sad red appears nearly as shaded. Thus, steer certain of the negate of red characters on shaded backgrounds, including blackboards.Display that shaded textual direct material and red textual direct material stumble on the same for protanopes. Colorblinds other folks, nonetheless, quiet in actuality feel certain ranges of reds as vivid and intellectual colors. Rather than pure sad red (RGB=100%, 0%, 0% or #FF.) , please negate vermilion (yellowish red with shorted wavelength: RGB=100%,32%,0% or #FF2000 ), or gentle red (blended with white: RGB=100%,8%,8% or #FF1414 ).

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Space of colors that is unambiguous both to colorblinds and non-colorblinds

Here’s a proposal of color pallet that is


1: unambiguous both to colorblinds and non-colorblinds,


2: with intellectual colors so as that color names are easy to call,


3: would possibly perhaps presumably be printable with an identical color both on mask and when printed.

• For red, vermilion is standard because it’s a ways recognizable additionally to protanopes.
• Colors between yellow and green are all shunned, since they are indistinguishable with yellow and orange.
• For green, bluish green is chosen so as that it couldn’t be puzzled with red or brown.
• Since violet is shut to blue and seem the same to colorblinds, reddish purple is chosen.
• Between vermilion and yellow, three colors with numerous obvious intensity is chosen.
• Sky blue and blue are chosen so as that they are distinguishable with there difference in brightness and saturation.
• Even for non-coloblinds, skinny traces and puny characters in blue and yellow are exhausting be taught. For skinny traces and puny objects, negate darker blue and orange is preferable to sky blue and yellow.

When combining colors from this pallet,

• Exhaust “warm” and “cool” colors alternatively.
• When the negate of two warm colors or two cool colors, place certain variations in brightness or saturation.
• Steer clear of aggregate of colors with low saturation or low brightness.

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When giving talks and lectures

Steer clear of indicating objects handiest by names

As shown in Fig. 4, the categorization of color would now not match between colorblinds and non-colorblinds. Even for vivid intellectual colors, colorblind other folks can now not customarily distinguish the name of colors. When explaining figures, steer certain of the negate of handiest color names and deliver additionally shapes or positions. For instance, steer certain of announcing “this red cell”. As a replace, affirm “this red, spherical cells on the tip left”, as an instance.

Inexperienced laser pointer

Fig. 17 Colorblind barrier-free color pallet

Since red laser pointers negate lengthy wavelength of gentle, it’s a ways infrequently sophisticated for colorblinds to scrutinize where is pointed. Recently, green laser pointers turns into readily available, whose color is inconspicuous to scrutinize both for colorblinds and nom-colorblinds.

The sunshine from one-milliwatt model is lawful for normal seminar room. A five-milliwatt model would be too vivid excluding in a incandescent auditorium.

• Beta Electronics, Inc.
  
  http://http://www.betalaser.com/
  
  
• DeHarpporte Shopping and selling Firm
  
  http://retailer.yahoo.com/deharpport/greenlaspoin.html
  
  

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Colorblind proofing (checker) tool

Vairous tool are in actuality readily available to envision whether your intellectual images will bring ample recordsdata to colorblind readers.

Photoshop / Illustrator CS4

The recent model of Adobe Photoshop CS4 and Illustrator CS4 (readily available come by Autumn 2008 for Windows and Macintosh) feature the CUD proof feature to envision whether your paintings bring recordsdata neatly for viewers who are colorblind. For the reason that feature is constructed into the color-management sysrtem, the conversion is snug and fleet.

This efficiency is developmed in collaboration between Adobe and Coloration In style Invent Group (CUDO), Kei Ito (University of Tokyo) and Mitsuyoshi Maekawa (Industrial Research Institute of Ishikawa).

• CUD proof for Photoshop
• CUD proof for Illustrator
• Adobe : http://www.adobe.com/
  

Vischeck

• Receive ImageJ
  
  http://rsb.recordsdata.nih.gov/ij/
  
  
• Receive VischeckJ 1.0 (Vischeck ImageJ Creep-In)
  
  http://www.vischeck.com/downloads/
  
  
• Online demonstration of Vischeck
  
  
  (upload your images and come by the conversion sent by blueprint of online)
  
  http://vischeck.com/vischeck/vischeckImage.php
• Receive Vischeck Creep-In for Adobe Photoshop (Windows)
  
  http://www.vischeck.com/downloads/
• Colorfield Perception : simulation plug-in for Adobe photoshop (Macintosh)
  
  

Colorblind proofing (checker) hardware

In 2007, LCD laptop shows with constructed-in circuit for colorblind proof are launched by EIZO/Nanao Company. For the reason that simulation utilizes the feature that is equiped handiest in excessive-cease monitors, they’re now not cheap (but now not that expensive compared with the same video show without colorblind simulation feature.) The coolest thing about hardware-essentially based fully simulation is that the simulation is performed on the soar. One can evaluation images with and without simulation regardless of the tool (e.g. photographs, vector drawings, PDFs, note documents, presentations, online pages, and so on.). Furthermore, one can additionally simulate films, TV packages, and games.

This efficiency is developmed in collaboration between Adobe and Coloration In style Invent Group (CUDO), Kei Ito (University of Tokyo) and Mitsuyoshi Maekawa (Industrial Research Institute of Ishikawa).

• Coloration vision deficiency simulation monitors
  
  http://www.eizo.com/merchandise/liquid crystal show/color_vision/index.asp
• A brochure “Coloration In style Invent Instruction handbook” (PDF file)
  
  http://www.eizo.com/merchandise/liquid crystal show/color_vision/handbook.pdf

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Display: When the negate of colorblind proofing systems (indispensable!)color>

• 1: It’s miles urged to negate an Adobe-RGB compliant video show moderately than an sRGB video show, for the reason that ragged avoids unintended color changes of the converted colors induced by out-of-gamut clipping.

• 2: Remember the truth that now not all colorblind other folks scrutinize colors as indicated within the colorblind proof. The converted views mimic the vision of the most strongly-affected sorts of colorblind other folks (dichromats). Many other colorblind other folks scrutinize colors in a more an identical formulation to other folks with traditional-kind color vision. Additionally, to compensate their complications in figuring out reddish hue, colorblind other folks are infrequently more sensitive to sophisticated variations in bluish hue, brightness, and texture of the coloured objects that traditional-kind other folks have a tendency to miss.

• 3: The color displayed within the colorblind proof is now not necessarily the color known by colorblind other folks. Within the proof, a range of colors that are sophisticated for colorblinds to distinguish are converted into one color. For instance, some shades of pink and sky blue are converted to the same sky blue within the proof, but it with no doubt is inaccurate to judge that “colorblind other folks scrutinize pink as sky blue.” (In such case colorblind other folks regard the color both as pink or blue reckoning on the context precise by which the coloured object appears.) Thus, the proof must handiest be standard for figuring out “which colors on the doc are sophisticated for them to grasp.” On this appreciate, colorblind proof is now not the true simulation of colorblind vision.

• 4: Attain now not grasp the aptitude of colorblind other folks by taking a scrutinize at colorblind proof images. Colorblind proof is developed for serving to non-colorblind designers, creators and scientists who want to manufacture their merchandise colorblind-pleasant. It’s miles now not developed for the individuals within the personnel division who want to evaluate the aptitude of the worker. Thanks to the explanations shown above (#2 and #3), many colorblind other folks can distinguish more colors than are seen within the colorblind proof. Even the strongest style of colorblind other folks fabricate the most of color- and texture recordsdata that non-colorblind peole infrequently omit. The flexibility of colorblind other folks must be judged strictly by their efficiency within the precise job, now not by what folks “imagine” about their capacity.

• 5: To carry out optimal Coloration In style Invent, it’s a ways additionally indispensable to now not rely entirely on the colorblind proof but additionally to quiz colorblind other folks to gaze your diagram and give advises. (On this case notice the individuals that are most strongly affected, as weakly affected other folks would possibly perhaps presumably additionally simply distinguish most colours that strongly affected other folks can now not.) Here is which potential of (a) even if the calculation formulation of the colorblind proof is designed to present legit results in as super dwelling of color dwelling as that you just would possibly perhaps additionally judge of, it customarily fails in vivid intellectual colors, and (b) colors have a tendency to seem in every other blueprint on the laptop mask when put next with the final merchandise/printed presents, where as well they are tormented by the lighting fixtures stipulations beneath which they are viewed.

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Coloration In style Invent Group

To magnify the activity to advertise colorblind-pleasant diagram now not handiest within the center of the ivory tower of scientists but additionally to industrial merchandise and public services, in Autumn 2004 we established a non-profit group known as the “Coloration In style Invent Group” (CUDO). CUDO homepage: http://www.cudo.jp/e/

We own helped designers who are working for the educate stations of Tokyo subway machine, Nationwide Science Museum, hospitals, textbooks for famous and excessive faculties, company annual experiences, catalogues, controler and Graphical User Interface of TV and DVD recorders, reproduction and fax machies, automobile navigation systems, digicams, and so on. Upon quiz, we deliver a Coloration In style Invent label (scrutinize above) to the services and merchandise whose colorblind-friendliness is improved drastically. Within the suggest time, the acrtivity of CUDO is particular essentially in Japan, but about a of the resulting merchandise are exported worldwide.

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PDF and PowerPoint recordsdata for brochure and presentation

Please in actuality be at liberty to negate these items to your classes and seminars. (Please form now not neglect, nonetheless, to point out Masataka Okabe and Kei Ito for reference.)

Related Papers (preprints)

• Coloration In style Invent -The selection of four without misfortune distinguishable colors for all color vision sorts-
  (preprint for the 2008 The Society for Imaging Science and Technology Meeting at San Jose)
  
  ichihara_etal_2008.pdf

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Acknowledgements

We thank Cahir O’Cane and John Mollon (Cambridge Univ.) for priceless dialogue. We additionally thank Kazuo Ikeo, Michina Shiraki and Shigeo Hayashi (Nationwide Institute of Genetics), Masakazu Yabuuchi (Olympus Co. Ltd.), Tomoko Hashimoto and Maki Kimura (Total Media) for images and drawings. Ideas from Mitsuyoshi Maekawa (Industrial Research Institute of Ishikawa), Kenji Kitahara, Makiko Ohkido (Jikei Medial College), Yasuyo Ichihara (Kogakuin Univ.), Kohei Musha (CUDO), Koichi Iga (CUDO) and Yosuke Tanaka (CUDO) were extremely priceless. The barrier-free and color-popular diagram logos are designed and copyrighted by Kohei Musha.

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