What is spinal concussion?Spinal cord concussion is a variant of mild spinal cord injury,clinically designated as transient paraplegia or neurapraxia,and characterized by variable degrees of sensory impairment and mo...What is spinal concussion?Spinal cord concussion is a variant of mild spinal cord injury,clinically designated as transient paraplegia or neurapraxia,and characterized by variable degrees of sensory impairment and motor weakness that typically resolve within 24–72 hours without permanent deficits(Del Bigio and Johnson,1989;Zwimpfer and Bernstein,1990;Torg et al.,1997).展开更多
The purpose of this paper is to survey the construction of orthogonal arrays of strength two by using difference sets. Some methods for constructing difference set D(2p.2p,p,2), where p is a prime or a prime power, ar...The purpose of this paper is to survey the construction of orthogonal arrays of strength two by using difference sets. Some methods for constructing difference set D(2p.2p,p,2), where p is a prime or a prime power, are given. It is shown that the Kronecker sum of a difference set D(λ1p, k1, p, 2) and an orthogonal array(λ2p2, k2, p, 2) leads to another orthogonal array (λ1λ2p3 .k1k2+1 ,p, 2). This enables us to construct orthogonal arrays[2p(n+1)、1+2(p+p2 +…+pn),p,2],[4p(n+2),1+2p+4(p2+p3+…+p(n+1)),p, 2],and [8p(n+3),1+2P+4p2+8(p3+p4+…+p(n+2)),p,2]where p is a prime or a prime power.展开更多
基金supported by NIH PO1 NS055976Craig H.Neilsen Foundation
文摘What is spinal concussion?Spinal cord concussion is a variant of mild spinal cord injury,clinically designated as transient paraplegia or neurapraxia,and characterized by variable degrees of sensory impairment and motor weakness that typically resolve within 24–72 hours without permanent deficits(Del Bigio and Johnson,1989;Zwimpfer and Bernstein,1990;Torg et al.,1997).
文摘The purpose of this paper is to survey the construction of orthogonal arrays of strength two by using difference sets. Some methods for constructing difference set D(2p.2p,p,2), where p is a prime or a prime power, are given. It is shown that the Kronecker sum of a difference set D(λ1p, k1, p, 2) and an orthogonal array(λ2p2, k2, p, 2) leads to another orthogonal array (λ1λ2p3 .k1k2+1 ,p, 2). This enables us to construct orthogonal arrays[2p(n+1)、1+2(p+p2 +…+pn),p,2],[4p(n+2),1+2p+4(p2+p3+…+p(n+1)),p, 2],and [8p(n+3),1+2P+4p2+8(p3+p4+…+p(n+2)),p,2]where p is a prime or a prime power.