AAD
AAD may refer to:
Aviation
Organizations
Medicine
People
Science and technology
ʿĀd
‘Ad (Arabic: عاد, ʿĀd) was an ancient tribe mentioned frequently in the Qur'an. ‘Ad is usually placed in the south of Arabia, in a location referred to as al-Ahqaf. The tribe's members, referred to as ‘Adites, formed a prosperous nation until destroyed in a violent storm after they had rejected the divine message preached by Hud. ‘Ad is regarded as one of the original Arab tribes, the "lost Arabs".
Legend
In local folklore, Hud and the tribe of ‘Ad have been linked to a legendary king ‘Ad, who ruled over a region whose capital was in "Wūbar".
Ontology of Quran
Aad are referred to in verse (11:60) of chapter (11) sūrat hūd (Hud): The verses related to this concept in the Quran (eg (7:65:2) refers to the second word of sura 7:65). There are 24 occurrences of concept of Aad in the Quran, namely (7:65:2)(7:74:7)(9:70:9)(11:50:2)(11:59:2)(11:60:10)(11:60:15) (14:9:9)(22:42:8)(25:38:1)(26:123:2)(29:38:1)(38:12:5)(40:31:5)(41:13:8)(41:15:2)(46:21:3) (50:13:1)(51:41:2)(53:50:3)(54:18:2)(69:4:3)(69:6:2)(89:6:6)
7-Aminoactinomycin D
7-Aminoactinomycin D (7-AAD) is a fluorescent chemical compound with a strong affinity for DNA. It is used as a fluorescent marker for DNA in fluorescence microscopy and flow cytometry. It intercalates in double-stranded DNA, with a high affinity for GC-rich regions, making it useful for chromosome banding studies.
Applications
With an absorption maximum at 546 nm, 7-AAD is efficiently excited using a 543 nm helium–neon laser; it can also be excited with somewhat lower efficiency using a 488 nm or 514 nm argon laser lines. Its emission has a very large Stokes shift with a maximum in the deep red: 647 nm. 7-AAD is therefore compatible with most blue and green fluorophores – and even many red fluorophores – in multicolour applications.
7-AAD does not readily pass through intact cell membranes; if it is to be used as a stain for imaging DNA fluorescence, the cell membrane must be permeabilized or disrupted. This method can be used in combination with formaldehyde fixation of samples.
Podcasts:
