There are six types or flavours of Quark. Which one is missing: up, down, bottom, top, strange and ........?
Bottom quark quarks. Although it almost-exclusively transitions from or to a top quark, the bottom quark can decay into either an up quark or charm quark via the weak interaction. CKM matrix elements "V" and "V" specify the rates, where both these decays are suppressed, making lifetimes of most bottom particles (~10 s) somewhat higher than those of charmed particles (~10 s), but lower than those of strange particles (from ~10 to ~10 s). The combination of high mass and low transition-rate gives experimental collision byproducts containing a bottom quark a distinctive signature that makes them relatively easy to identify using a
Top-down and bottom-up design A bottom-up approach allows for more experimentation and a better feeling for what is needed at the bottom. Other evidence suggests that there is a third combination approach to change (see Stewart, Manges, Ward, 2015). Both top-down and bottom-up approaches exist in public health. There are many examples of top-down programs, often run by governments or large inter-governmental organizations (IGOs); many of these are disease-specific or issue-specific, such as HIV control or Smallpox Eradication. Examples of bottom-up programs include many small NGOs set up to improve local access to healthcare. However, a lot of programs seek to combine both approaches;