The word 'efficiently' here means up to polynomial-time reductions . This thesis was originally called Computational Complexity-Theoretic Church–Turing Thesis by Ethan Bernstein and Umesh Vazirani (1997). The Complexity-Theoretic Church–Turing Thesis, then, posits that all 'reasonable' models of computation yield the same class of problems that can be computed in polynomial time. Assuming the conjecture that probabilistic polynomial time ( BPP ) equals deterministic polynomial time ( P ), the word 'probabilistic' is optional in the Complexity-Theoretic Church–Turing Thesis. A similar thesis, called the Invariance Thesis , was introduced by Cees F. Slot and Peter van Emde Boas. It states: "Reasonable" machines can simulate each other within a polynomially bounded overhead in time and a constant-factor overhead in space .  The thesis originally appeared in a paper at STOC '84, which was the first paper to show that polynomial-time overhead and constant-space overhead could be simultaneously achieved for a simulation of a Random Access Machine on a Turing machine. 
late 13c., "restorative powers of the body, bodily processes; powers of growth;" from Old French nature "nature, being, principle of life; character, essence," from Latin natura "course of things; natural character, constitution, quality; the universe," literally "birth," from natus "born," past participle of nasci "to be born," from PIE *gene- "to give birth, beget" (see genus ).
From late 14c. as "creation, the universe;" also "heredity, birth, hereditary circumstance; essential qualities, innate disposition" (. human nature ); "nature personified, Mother Nature." Specifically as "material world beyond human civilization or society" from 1660s. Nature and nurture have been contrasted since 1874. Nature should be avoided in such vague expressions as 'a lover of nature,' 'poems about nature.' Unless more specific statements follow, the reader cannot tell whether the poems have to do with natural scenery, rural life, the sunset, the untouched wilderness, or the habits of squirrels." [Strunk & White, "The Elements of Style," 3rd ed., 1979]
well it depends on if it is an on purpose abortion or like you have to get rid of the baby. I had an experience that i had to evacuate the baby, and that is what I wrote on my essay.
It is not easy to be a mom. Being a mother is not all about carrying the baby for nine months. It’s about how the mother feels and thinks about the baby. Mothers worry about the baby’s health. A lot of them are concerned about the baby’s heart, brain, and lungs because once those body parts are good, then everything else will be great as well. It takes a lot to have a child, but what if the baby’s health is already in bad condition, what is there for the mother to do if she or the baby will be hurt, and whose life is more significant mom or baby?