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This is a webcam video of me alone at home in my darkened room in the middle of the day reading from the amazing Twitter Nihlist Arbys. As you can see, outside my bedroom window is the wall of the house next door. This was what I was doing on a normal Saturday afternoon, because you know there's nothing really worth doing in life so why not? Whatever. Why even bother getting out of bed? It's not like any of this matters. Nuggets used to be chickens. Life was and always will be pain. #NihlistArbys
El Presidente del Congreso de la República, José Williams Zapata, se reunió con el Presidente del Consejo de Ministros , Alberto Otárola (Fotos: Congreso de la República / Ernesto Arias)
El Presidente del Congreso de la República, José Williams Zapata, se reunió con el Presidente del Consejo de Ministros , Alberto Otárola (Fotos: Congreso de la República / Ernesto Arias)
El Presidente del Congreso de la República, José Williams Zapata, se reunió con el Presidente del Consejo de Ministros , Alberto Otárola (Fotos: Congreso de la República / Ernesto Arias)
Explaining the significance of the signage on the rooftop, as throwback to the Sears & Roebuck days.
El Presidente del Congreso de la República, José Williams Zapata, se reunió con el Presidente del Consejo de Ministros , Alberto Otárola (Fotos: Congreso de la República / Ernesto Arias)
Image showing microscopic asbestos fibers (amosite) and other ambient particles under 400x magnification using Phase-Contrast Microscopy (PCM) optical illumination method.
Although certain technical fiber-counting rules prohibit "identification" of specific fiber types using the PCM technique, this example depicts a reference slide with a known type of fiber; in this case, amosite asbestos fibers. Note characteristic parallel splitting, straightness, narrow width, and splayed ends of the fibers (fiber bundles).
The visible "fibers" in the image are actually bundles of yet further bundles of "fibers". One of the more distinguishing features of asbestos is its incredible capacity to subdivide into increasingly smaller and thinner fibers (far beyond the resolution of this microscopy method); until the fiber may reach its ultimate particle size: the individual unit fibril (on the order of angstroms and nanometers).
Among other scientific applications, PCM is a fairly common, standard analytical technique utilized for testing air monitoring samples for airborne fiber concentrations pertaining to asbestos-related work, such as projects related to: abatement, repair, clean-up, worker exposure, ambient background, etc. Further, PCM equipment is relatively inexpensive, portable, and sturdy enough that it can be setup directly on many project sites, a particularly convenient advantage. This testing method is currently so routine, that if one is familiar with an asbestos abatement work project, it's quite likely that PCM air monitoring is involved.
However, while used as an acceptable standard method for determining worker exposure levels to airborne fiber concentrations and for "clearance" of post-abatement work areas, there are a number of significant issues regarding over-reliance of PCM for airborne asbestos detection.
One main cause for concern are serious limitations of PCM's optical resolution. Unknown quantities of asbestos fibers may not be discernible using PCM, which can be better detected using more advanced and asbestos-specific imaging techniques such as transmission-electron microscopy (TEM). PCM may be considered more as a basic "screening" method although possibly inadequate for truly accurate analyses of airborne asbestos fiber concentrations; another debate that typically boils down to Health vs. Cost.
Also depicted, is a standardized Walton-Beckett graticule with incremental graduated x-y axes measured in micrometer units; diameter is approx. 100-µm across. Encircling the graticule area are measured scale markers in 3:1 length-to-width aspect ratio for visual reference. The green color is from a green-tinted light filter.