Id |
Subject |
Object |
Predicate |
Lexical cue |
T48 |
0-19 |
Sentence |
denotes |
Materials & methods |
T49 |
20-64 |
Sentence |
denotes |
The experimental setup is shown in Figure 1. |
T50 |
65-307 |
Sentence |
denotes |
The aerosol consisted of 10% NaCl in water from a nebulizer (Omron NE-C28P, mass median aerodynamic diameter of 3 μm) fed through one of the lung ports of a dummy head (Laerdal airway management trainer) lying face upward on an optical bench. |
T51 |
308-504 |
Sentence |
denotes |
Prior to measurement, the airway was primed with aerosol by turning on the nebulizer briefly while squeezing the attached lung ten-times, then waiting for 30 s for the exhaled aerosol to disperse. |
T52 |
505-658 |
Sentence |
denotes |
A fume extractor was running continuously above the head (ULT Jumbo Filter Trolley 2.0 running at 0.3 m/s in a position 15 cm above the tip of the nose). |
T53 |
659-750 |
Sentence |
denotes |
After initiating the camera acquisition, the lung was squeezed by hand to deliver a breath. |
T54 |
751-830 |
Sentence |
denotes |
These were measured to deliver 300 ml quite reproducibly (wright respirometer). |
T55 |
831-952 |
Sentence |
denotes |
For the breath duration of 1 s, the average flow of 0.3 l/s is similar to the peak flow for a normal breath 0.5 m/s [26]. |
T56 |
953-1104 |
Sentence |
denotes |
The aerosol was visualized with a conical laser sheet generated with a 488 nm DPSS laser (Coherent Sapphire 75 mW) and axicon lens (Thorlabs AX1220-A). |
T57 |
1105-1266 |
Sentence |
denotes |
The conical cyan sheet surrounds the face at a distance of approximately 2.5 cm from the nose and at a closer distance at the cheek to allow space for the masks. |
T58 |
1267-1367 |
Sentence |
denotes |
A beam block was used at the axicon’s aperture to prevent direct illumination of parts of the dummy. |
T59 |
1368-1377 |
Sentence |
denotes |
Figure 1. |
T60 |
1379-1449 |
Sentence |
denotes |
Photographs of the setup, showing the laser cone on an unmasked dummy. |
T61 |
1450-1596 |
Sentence |
denotes |
The extractor is turned off to enhance laser appearance (A) view from the left (B) view from top parallel to laser (C) view from the right bottom. |
T62 |
1597-1695 |
Sentence |
denotes |
The camera was a 2048*2048 pixel sCMOS array (Andor Sona 4BV11) with Nikkor 50 mm F1.8 AI MF lens. |
T63 |
1696-1768 |
Sentence |
denotes |
It recorded a sequence of 30 frames at 7 Hz (acquisition time of 10 ms). |
T64 |
1769-1904 |
Sentence |
denotes |
Raw 16-bit images were processed in SAOimage DS9 by applying the ‘bb’ colormap on a value range of 100–20,000 counts using log scaling. |
T65 |
1905-1952 |
Sentence |
denotes |
The masks and dummy used are shown in Figure 2. |
T66 |
1953-2124 |
Sentence |
denotes |
The three-layer mask in Figure 2B has two outer layers each 0.4-mm thick made of 80% polyester 20% elastane with the internal filter layer being 1.0 mm 100% polypropylene. |
T67 |
2125-2248 |
Sentence |
denotes |
The filter covers the area of the mouth and nose but around chin, cheeks and nose bridge the fabric is just a single layer. |
T68 |
2249-2371 |
Sentence |
denotes |
Compliance with the testing methods of the CWA 17553 was claimed by the supplier but packaging was not marked accordingly. |
T69 |
2372-2381 |
Sentence |
denotes |
Figure 2. |
T70 |
2383-2417 |
Sentence |
denotes |
Photographs of the test materials. |
T71 |
2418-2527 |
Sentence |
denotes |
(A) the unmasked dummy, (B) three-layer mask with middle filter layer removed, (C) single-layer textile mask. |
T72 |
2528-2642 |
Sentence |
denotes |
Bottom row: (D) CE marked FFP1 personal protective equipment mask, (E) CE marked Type 2 medical mask, (F) bandana. |
T73 |
2643-2766 |
Sentence |
denotes |
The single layer mask in Figure 2C is of unknown 1.0-mm thick material, of a design which was cheaply and widely available. |
T74 |
2767-2809 |
Sentence |
denotes |
Compliance with CWA 17553 was not claimed. |
T75 |
2810-2924 |
Sentence |
denotes |
The CE-marked FFP1 respirator mask in Figure 2D has no exhalation valve and it is marked as complying with EN 149. |
T76 |
2925-3037 |
Sentence |
denotes |
The CE-marked type 2 medical mask in Figure 2E had a metal nose clip which was cinched down firmly on the dummy. |
T77 |
3038-3090 |
Sentence |
denotes |
The packaging was marked as complying with EN 14683. |
T78 |
3091-3220 |
Sentence |
denotes |
The bandana or neck gaiter in Figure 2(f) was 0.33 mm thick 100% polyester and was folded into three layers in these experiments. |
T79 |
3221-3356 |
Sentence |
denotes |
Dating from 2019 this was never intended for infection control, although the same material has been seen to be used as a face covering. |