928 resultados para radius of starlikeness


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Top Row: Dereje Amente, Grace Baek, Anne Benitez, Anna Berry-Krumrey, Amber Blake, Daniela Bravo-Corona, Shelley Brenner, Melissa Butzky, Ann Cassel, Chantal Chin, Mee-Sook Choo, Stephanie Clapham, Kathryn Clark, Joseph Cleary, Stephanie Conn, Casie Cook

Row 2: Christina Cook, Jessica Cook, Renea Cox, Marissa DaSilva, Kathryn Davenport, Ashley Deford, Alyse DeHaan, Maria Didio, Alyssa Diroff, Amy Doenitz, Emily Domansky, Deanna Dong, Ross Drake, Brian Dulzo, Michelle Dwyer, Jill Eberly, Rachel Escobar, Kathryn Falvey

Row 3: Michelle Fauver, Paula Fe Francisco, Lindsey Frick, Amannda Casper, Ashley Pickett, Kristin Kingma, Thomas Donnelly, Danielle Besk, Kimberly Cristobal, Heather Erdmann, Jessica Kramer, Ana Kotsogiannis, Sarah Bloom, Anna Evola, Melissa Dulic, Anna Garcia, Christopher Gargala, Thomas Geigert

Row 4: Megan Giles, Kristen Gniewkowski, Alexandra Gold, Sarah Gorzalski, Michele Grabow, Amber Gramling, Hannah Gregerson, Maria Hegan, Wendy Hastings, Ahsley Hayner

Row 5: Leanne Heilig, Lauryn Hildensperger, Rachel Hollern, Laura Jean Howatt, Eve Jaehnen, Stephanie Johnson, Peter Kachur, Rachelle Kilburg, Rachel Klein, Sara Klok, Caitlyn Kochanski, Valerie Kotal

Row 6: Lidia Kraft, Allison Kruger, Omotara Kufeji, Jill Kuhlman, Karah Kurdys, Kathryn Lang, Elsa Lindquist, Sara Mangus, Kathryn Marten, Samantha Maskell, Lauren McBride, Kelly McCarley

Row 7: Rachel McClure, Angela McCracken, Mallory Missad, Kathleen Murray, Mariko Nakagawa, Jaclyn Nancekivell, Tracey Negrelli, Kathleen Potempa, Bonnie Hagerty, Healee On, Sarah Osentoski, Kelsey Owens, Kelly Paulisin, Amanda Phillips, Emily Pressley, Kaitlyn Radius

Row 8: Rebecca Reits, Elin Ridenour, Amanda Robbins, Chayla Robles, Jessica Roossien, Alyssa Roy, Leslie Russell, Kristen Ruster, Cynthia Scheuher, Julie Schramm, Kim Schroers, Jennifer Schwartz, Kelly Seestedt, Shannon shank, Andrea Sherzer, Lauren Sir, Erinn Smith, Kathleen Soedarjatno

Row 9: Jessica Stefko, Alexandra Stencel, Brianne Stowell, Alexandra Suseland, Lauren Taylor, Deborah Thornton, Amanda Timmer, Daniel Tjarks, Jillian Traskos, Graham Valley, Sarah Wade, Rachel Wagner, Drew Wakefield, Marlena Westerlund, Katie Wheelock, Jennifer Wilcox, Dana York

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Experiments carried out to investigate the reproductive ecology of the Australian cycad Lepidozamia peroffskyana (Regal, Bull. Soc. Imp. Nat. Mosc. 1857, 1: 184) revealed that this species is pollinated exclusively by host-specific Tranes weevils (Pascoe 1875). The weevils carry out their life cycle within the tissues of the male cones but also visit the female cones in large numbers. Female cones from which insects ( but not wind) were excluded had a pollination rate that was essentially zero. In contrast, female cones from which wind ( but not insects) were excluded had a pollination rate comparable with naturally pollinated cones. Assessment of Tranes weevil pollen load indicated that they are effective pollen-carriers. No other potential insect pollinators were observed on cones of L. peroffskyana. Sampling of airborne loads of cycad pollen indicated that wind-dispersed grains were not consistently recorded beyond a 2-m radius surrounding pollen-shedding male cones. The airborne load of cycad pollen in the vicinity of pollination-receptive female cones was minimal, and the spatial distribution of the coning population indicated that receptive female cones did not usually occur close enough to pollen-shedding male cones for airborne transfer of pollen to explain observed natural rates of seed set. These multiple lines of evidence suggest that wind-once considered the only pollination vector for cycads and other gymnosperms-plays only a minimal role in the pollination of L. peroffskyana, if any at all. The global diversity of insects associated with cycads suggests that some lineages of pollinating beetles may have been associated with cycad cones since Mesozoic times.

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The effects of different concentrations of individual additions of rare earth metals (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) on eutectic modification in Al-10mass%Si has been studied by thermal analysis and optical microscopy. According to the twin-plane re-entrant edge (TPRE) and impurity induced twinning mechanism, rare earth metals with atomic radii of about 1.65 times larger than that of silicon, are possible candidates for eutectic modification. All of the rare earth elements caused a depression of the eutectic growth temperature, but only Eu modified the eutectic silicon to a fibrous morphology. At best, the remaining elements resulted in only a small degree of refinement of the plate-like silicon. The samples were also quenched during the eutectic arrest to examine the eutectic solidification modes. Many of the rare-earth additions significantly altered the eutectic solidification mode from that of the unmodified alloy. It is concluded that the impurity induced twinning model of modification, based on atomic radius alone, is inadequate and other mechanisms are essential for the modification process. Furthermore, modification and the eutectic nucleation and growth modes are controlled independently of each other.