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We present a new worldwide phylogenetic classification of 11 506 grass species in 768 genera, 12 subfamilies, seven supertribes, 52 tribes, five supersubtribes, and 90 subtribes; and compare two phylogenetic classifications of the grass family published in 2015 (Soreng et al. and Kellogg). The subfamilies (in descending order based on the number of species) are Pooideae with 3968 species in 202 genera, 15 tribes, and 30 subtribes; Panicoideae with 3241 species in 247 genera, 13 tribes, and 19 subtribes; Bambusoideae with 1670 species in 125 genera, three tribes, and 15 subtribes; Chloridoideae with 1602 species in 124 genera, five tribes, and 26 subtribes; Aristidoideae with 367 species in three genera, and one tribe; Danthonioideae with 292 species in 19 genera, and one tribe; Micrairoideae with 184 species in eight genera, and three tribes; Oryzoideae with 115 species in 19 genera, four tribes, and two subtribes; Arundinoideae with 40 species in 14 genera, two tribes, and two subtribes; Pharoideae with 12 species in three genera, and one tribe; Puelioideae with 11 species in two genera, and two tribes; and the Anomochlooideae with four species in two genera, and two tribes. We also include a radial tree illustrating the hierarchical relationships among the subtribes, tribes, and subfamilies. Newly described taxa include: supertribes Melicodae and Nardodae; supersubtribes Agrostidodinae, Boutelouodinae, Gouiniodinae, Loliodinae, and Poodinae; and subtribes Echinopogoninae and Ventenatinae.

Five ATP-binding cassette (ABC) subfamily-A transporters (ABCA1, ABCA2, ABCA3, ABCA7 and ABCA8) are expressed in the brain. These transporters may regulate brain lipid transport; however, their relative expression level in isolated human brain cells is unknown. We developed real-time polymerase chain reaction assays to quantify the expression of these genes in human neurons, astrocytes, oligodendrocytes, microglia and cell lines. Neurons expressed predominantly ABCA1 and ABCA3; astrocytes ABCA1, ABCA2 and ABCA3; microglia ABCA1 and oligodendrocytes ABCA2 and ABCA3. Although ABCA7 and ABCA8 expression was relatively low in all cells, the highest expression occurred in microglia and neurons, respectively. ABCA gene expression in the NTERA-2 and MO3.13 cell lines closely resembled the ABCA expression pattern of primary neurons and oligodendrocytes, respectively. © 2006 Lippincott Williams & Wilkins.

Five ATP-binding cassette (ABC) subfamily-A transporters (ABCA1, ABCA2, ABCA3, ABCA7 and ABCA8) are expressed in the brain. These transporters may regulate brain lipid transport; however, their relative expression level in isolated human brain cells is unknown. We developed real-time polymerase chain reaction assays to quantify the expression of these genes in human neurons, astrocytes, oligodendrocytes, microglia and cell lines. Neurons expressed predominantly ABCA1 and ABCA3; astrocytes ABCA1, ABCA2 and ABCA3; microglia ABCA1 and oligodendrocytes ABCA2 and ABCA3. Although ABCA7 and ABCA8 expression was relatively low in all cells, the highest expression occurred in microglia and neurons, respectively. ABCA gene expression in the NTERA-2 and MO3.13 cell lines closely resembled the ABCA expression pattern of primary neurons and oligodendrocytes, respectively. © 2006 Lippincott Williams & Wilkins.

Five ATP-binding cassette (ABC) subfamily-A transporters (ABCA1, ABCA2, ABCA3, ABCA7 and ABCA8) are expressed in the brain. These transporters may regulate brain lipid transport; however, their relative expression level in isolated human brain cells is unknown. We developed real-time polymerase chain reaction assays to quantify the expression of these genes in human neurons, astrocytes, oligodendrocytes, microglia and cell lines. Neurons expressed predominantly ABCA1 and ABCA3; astrocytes ABCA1, ABCA2 and ABCA3; microglia ABCA1 and oligodendrocytes ABCA2 and ABCA3. Although ABCA7 and ABCA8 expression was relatively low in all cells, the highest expression occurred in microglia and neurons, respectively. ABCA gene expression in the NTERA-2 and MO3.13 cell lines closely resembled the ABCA expression pattern of primary neurons and oligodendrocytes, respectively. © 2006 Lippincott Williams & Wilkins.

Five ATP-binding cassette (ABC) subfamily-A transporters (ABCA1, ABCA2, ABCA3, ABCA7 and ABCA8) are expressed in the brain. These transporters may regulate brain lipid transport; however, their relative expression level in isolated human brain cells is unknown. We developed real-time polymerase chain reaction assays to quantify the expression of these genes in human neurons, astrocytes, oligodendrocytes, microglia and cell lines. Neurons expressed predominantly ABCA1 and ABCA3; astrocytes ABCA1, ABCA2 and ABCA3; microglia ABCA1 and oligodendrocytes ABCA2 and ABCA3. Although ABCA7 and ABCA8 expression was relatively low in all cells, the highest expression occurred in microglia and neurons, respectively. ABCA gene expression in the NTERA-2 and MO3.13 cell lines closely resembled the ABCA expression pattern of primary neurons and oligodendrocytes, respectively. © 2006 Lippincott Williams & Wilkins.

Let E_m be the family of elliptic curves given by y^2=x^3-x+m^2, which has rank 2 when regarded as an elliptic curve over Q(m). (Here Q represents the field of rational numbers.) Brown and Myers show that a certain quadratic polynomial m(t) has the property that E_m(t) contains an additional rational point that is independent from the two original generators. This implies that there are infinitely many rational numbers n such that E_n(Q) has rank at least 3. We generalize this result, showing that every nonzero rational number n has the property that E_n sits inside such a subfamily of rank 3. Moreover, given any rational point P in E_n, there exists a quadratic polynomial m(t) and a Q(t)-point R(t) in E_m(t) that is independent from the original generators, such that the specialization to t=0 gives m(0)=n and R(0)=P. Such subfamilies can be intersected to increase the rank, demonstrating the existence of a rational subfamily of rank 4 over Q(t), and infinitely many rational numbers n such that E_n(Q) has rank at least 5. Shioda's theory of Mordell-Weil lattices is used to find the generators of such E_m(t) over both Qbar(t) and Q(t) in these cases. (Here Qbar represents the algebraic closure of Q.) All quadratic polynomials m(t) are classified by whether or not E_m(t) contains an additional rational point of low degree. Results similar to these are also obtained for other families of elliptic curves.