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LitCovid-PubTator

Id Subject Object Predicate Lexical cue tao:has_database_id
98 2362-2369 Species denotes ferrets Tax:9669
99 2473-2483 Species denotes SARS-CoV-2 Tax:2697049
101 3310-3315 Species denotes human Tax:9606

LitCovid-sentences

Id Subject Object Predicate Lexical cue
T101 0-10 Sentence denotes Discussion
T102 11-160 Sentence denotes The FFP1 mask is the only one which must pass a fit test to be awarded a CE mark, and indeed it showed the lowest leakage and undetected penetration.
T103 161-318 Sentence denotes For the other mask types, the fabrics with lower penetration showed higher leakage, indicating that these masks displayed a trade-off between fabric and fit.
T104 319-419 Sentence denotes The scattering of light by small particles is described by Mie theory [27], and is quite non linear.
T105 420-620 Sentence denotes However, using the experimental setup described herein, these nonlinearities will smooth over to a large extent due to the breadth and angle of the laser cone, and wide distribution of particle sizes.
T106 621-717 Sentence denotes The brightness can, therefore, be taken as approximately proportional to the volume of material.
T107 718-894 Sentence denotes Although it is possible to extract pseudo-quantitative results from these images by merely summing up the brightness of each pixel, we caution against doing so for two reasons.
T108 895-1055 Sentence denotes As seen in the no-mask image (Figure 3A), a narrow, fast-moving jet appears dim due to the small area of laser sheet it covers, despite carrying a large volume.
T109 1056-1120 Sentence denotes This weakness could be addressed by more complex image analysis.
T110 1121-1211 Sentence denotes Another caveat is that the results are dependent on the exact position of the laser sheet.
T111 1212-1327 Sentence denotes In the configuration used in the current study, for example, any leakage from under the chin would not be detected.
T112 1328-1470 Sentence denotes However, when using additional laser sheets, it is apparent that almost all leakage occurs around the eyes and cheeks for the masks we tested.
T113 1471-1583 Sentence denotes These additional laser sheets complicate the interpretation of the images, even if using different laser colors.
T114 1584-1722 Sentence denotes Directing the cone straight onto the face to form a laser ring around the masks results in a large background scatter from the dummy skin.
T115 1723-1880 Sentence denotes Although this background can be reduced by black paint and image processing, this configuration would then require another laser sheet to detect penetration.
T116 1881-2098 Sentence denotes It is also important to note that the aerosol used in the current experimental setup has a mass median aerodynamic diameter of 3 μm but is also a broad distribution with 10% of the mass in particles larger than 10 μm.
T117 2099-2249 Sentence denotes This covers the range of particle sizes emitted from speech [28], but whether this also correlates to the infectious particles is not currently known.
T118 2250-2328 Sentence denotes Most of the fabric testing to date has focused on submicron particles [29,30].
T119 2329-2468 Sentence denotes However, a study of influenza in ferrets found the disease was transmitted in particles larger than 1.5 μm, but not smaller particles [31].
T120 2469-2580 Sentence denotes For SARS-CoV-2, we do not yet know which size of the aerosol is likely to carry the most infectious viral load.
T121 2581-2650 Sentence denotes Larger particles are more likely to be captured by the mask material.
T122 2651-2785 Sentence denotes To an extent this is also true for leaks, as larger particles are more likely to deposit due to impaction when passing around corners.
T123 2786-2861 Sentence denotes It is also unknown how different leakage patterns could affect infectivity.
T124 2862-3025 Sentence denotes Even the worst performing single-layer mask served to slow down the flow from the mouth, which would reduce the spread of particles even if they were not captured.
T125 3026-3118 Sentence denotes The fate of leakage jets directed to the side, or upward, would depend on the local airflow.
T126 3119-3321 Sentence denotes Furthermore, the dummy head used in this study is larger than 95% of adult male heads (tip of the nose to the back of head 237 mm), meaning that the masks were a tighter fit than the average human head.
T127 3322-3418 Sentence denotes The exact shape of the nose would also have a potentially considerable influence on the leakage.
T128 3419-3546 Sentence denotes Nonetheless, despite these limitations, our preliminary findings are clear – mask efficacy is dependent on both fabric and fit.