Grassland Bird Monitoring at Agate Fossil Beds National Monument, Nebraska and Tallgrass Prairie National Preserve, Kansas

During the breeding seasons of 2001 through 2003, a total of 517 variable circular plots were surveyed for birds and assessed for habitat composition at Agate Fossil Beds National Monument, Nebraska and Tallgrass Prairie National Preserve, Kansas. Systematic 400 x 400 meter grids, originating from random start points, were used to locate 40 permanent variable circular plots in upland habitat at Agate Fossil Beds National Monument and 242 at Tallgrass Prairie National Preserve. An additional 14 permanent plots were established in the less common but important riparian habitat at Agate Fossil Beds National Monument, and 18 plots were added in riparian areas at Tall grass Prairie National Preserve. Variable circular plots in riparian habitat were spaced at 250 meter intervals throughout each area

Trans-Di-μ-acetato-[μ-N,N-bis-(diphenyl-phosphino)aniline] bis-[chlorido-molybdenum(II)](Mo - Mo)-dichloro-methane-tetra-hydro-furan (1/0.3/1.7)

The mol-ecular structure of the title compound, [Mo2(CH 3COO)2Cl2(C30H25NP 2)]·0.3CH2Cl2·1.7C 4H8O, features an Mo - Mo dumbbell bridged by two acetate groups which are trans to each other. Perpendicular to the plane spanned by the acetate groups, the Ph2PN(Ph)PPh2 ligand bridges both Mo atoms, having a P - N - P angle of 114.09 (19)°. In a trans position to the PNP ligand are two Cl atoms, one on each molybdenum centre. The Mo - Mo bond distance is 2.1161 (9) Å, within the range known for Mo - Mo quadruple bonds. The Mo complex is located on a crystallographic twofold rotation axis which runs through the N - C bond of the ligand. The site occupation factors of the disordered solvent molecules were fixed to 0.15 for dichloromethane and 0.85 for tetrahydrofuran. © 2009

Effects of Retained Pine and Hardwood Basal Areas on Percent Cover of Plants Utilized by Bobwhite Quail

Percent cover of seven forage species utilized by bobwhite quail (Colinus virginianus) was determined before thinning and 2 and 4 years after thinning a 35-year-old loblolly pine-hardwood stand. Combinations of three loblolly pine (15, 18, and 21 m2/ha) and three hardwood (0, 3.5, and 7 m2/ha) basal areas were replicated three times. Percent cover was determined for American beautyberry (Callicarpa americana), blackberry (Rubus spp.), tick trefoil (Desmodium spp.), lespedeza (Lespedeza spp.), panic grass (Panicum spp.), yellow wood sorrel (Oxalis stricta), and three-seeded mercury (Acalypha spp.). Percent cover of American beautyberry and blackberry increased with time. Tick trefoil and panic grass were negatively related to time after thinning. However, lespedeza, yellow wood sorrel, and three-seeded mercury were not influenced significantly by time after thinning. Blackberry and panic grass were negatively related to pine basal area, while all other plant species were not affected. Three-seeded mercury was the only species not negatively related to hardwood basal area. Canopy cover and relative light intensity in the understory demonstrated an inverse relationship

Diacetonitrile[N,N′-bis(2,6-diisopropyl-phenyl)ethane-1,2-diimine] dichloridochromium(II) acetonitrile solvate

The title compound, [CrCl2(CH3CN)2(C 26H36N2)]·CH3CN, was synthesized by the reaction of CrCl2(THF)2 with N,N′-bis-(2,6- diisopropyl-phen-yl)ethane-1,2-diimine in dichloro-methane/acetonitrile. The chromium center is coordinated by two N atoms of the chelating diimine ligand, two chloride ions in a trans configuration with respect to each other, and by two N atoms of two acetonitrile mol-ecules in a distorted octa-hedral geometry

Stability of accretion disk around rotating black holes: a pseudo-general-relativistic fluid dynamical study

We discuss the solution of accretion disk when the black hole is chosen to be rotating. We study, how the fluid properties get affected for different rotation parameters of the black hole. We know that no cosmic object is static in Universe. Here the effect of the rotation of the black hole to the space-time is considered following an earlier work of the author, where the pseudo-Newtonian potential was prescribed for the Kerr geometry. We show that, with the inclusion of rotation of the black hole, the valid disk parameter region dramatically changes and disk becomes unstable. Also we discuss about the possibility of shock in accretion disk around rotating black holes. When the black hole is chosen to be rotating, the sonic locations of the accretion disk get shifted or disappear, making the disk unstable. To bring it in the stable situation, the angular momentum of the accreting matter has to be reduced/enhanced (for co/counter-rotating disk) by means of some physical process.Comment: 24 Latex pages including 7 figures; Accepted for publication in Astrophysical Journa

[2,2-Bis(diphenylphosphanyl)propane κ2P,P0] tetracarbonylchromium(0)dichloromethane monosolvate

The title compound, [Cr(C27H26P2)(CO) 4]·CH2Cl2, was obtained by the reaction of Ph2PCMe2PPh2 with Cr(CO)6 in refluxing toluene by substitution of two carbonyl ligands. The CrC 4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 70.27 (2)°

[N,N-Bis(diphenyl­phosphino)isopropyl­amine]dibromidonickel(II)

The title compound, [NiBr2(C27H27NP2)], was synthesized by the reaction of NiBr2(dme) (dme is 1,2-dimethoxy-ethane) with N,N-bis-(diphenyl-phosphino)isopropyl-amine in methanol/tetra-hydro-furan. The nickel(II) center is coordinated by two P atoms of the chelating PNP ligand, PH2PN(iPr)PPH2, and two bromide ions in a distorted square-planar geometry

1,1,2,2-Tetra-phenyl-15-diphosphane 1-sulfide

In the title mol-ecule, C24H20P2S, the P - P bond length is 2.2263 (5) Å. The two phenyl rings attached to the three- and five-coordinated P atoms, respectively, form dihedral angles of 56.22 (5) and 71.74 (5)°

Quantitative Analysis of Protein Dynamics during Asymmetric Cell Division

SummaryIn dividing Drosophila sensory organ precursor (SOP) cells, the fate determinant Numb and its associated adaptor protein Pon localize asymmetrically and segregate into the anterior daughter cell, where Numb influences cell fate by repressing Notch signaling. Asymmetric localization of both proteins requires the protein kinase aPKC and its substrate Lethal (2) giant larvae (Lgl) [1–3]. Because both Numb and Pon localization require actin and myosin [4–6], lateral transport along the cell cortex has been proposed as a possible mechanism for their asymmetric distribution [5]. Here, we use quantitative live analysis of GFP-Pon and Numb-GFP fluorescence and fluorescence recovery after photobleaching (FRAP) to characterize the dynamics of Numb and Pon localization during SOP division. We demonstrate that Numb and Pon rapidly exchange between a cytoplasmic pool and the cell cortex and that preferential recruitment from the cytoplasm is responsible for their asymmetric distribution during mitosis. Expression of a constitutively active form of aPKC impairs membrane recruitment of GFP-Pon. This defect can be rescued by coexpression of nonphosphorylatable Lgl, indicating that Lgl is the main target of aPKC. We propose that a high-affinity binding site is asymmetrically distributed by aPKC and Lgl and is responsible for asymmetric localization of cell-fate determinants during mitosis