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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The uses of sodium selenate, P-40, and parathion in the control of red spider on ageratum.

Lembach, John Vincent 01 January 1948 (has links) (PDF)
No description available.
2

The life history of the Garman spider mite, Eotetranychus uncatus Garman.

Ubertalli, James Arthur 01 January 1954 (has links) (PDF)
No description available.
3

Major ampullate silk characterization of molecular structure and material properties /

Motriuk-Smith, Dagmara. January 2005 (has links)
Thesis (Ph. D.)--University of Wyoming, 2005. / Title from PDF title page (viewed on Feb. 22, 2008). Includes bibliographical references (p. 75-87).
4

Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas

Henderson, Takesha Yvonne 02 June 2009 (has links)
Lick Creek Park is a 515 acre nature park that was acquired in 1987 by the City of College Station, Texas. The site has a variety of indigenous plant and animal species and is an important natural resource for citizens of the region. There is a long-term commitment to inventory this natural park to monitor the changes as our urban community expands to surround the park. There are 989 species of spiders currently recorded from Texas and 332 of them are known to occur in Brazos County. My focus was on improving the ground spider inventory at Lick Creek Park. Spider collections were made using 18 regularly-sampled pitfall traps distributed evenly among three habitats. Spiders from 24 families, 66 genera, and 111 species were identified from 918 specimens, including 627 immature and 291 adult spiders, captured in pitfall traps from April 2005-April 2006. Of the 111 species found, 45 were represented by one specimen only and 20 were represented by two specimens. Rarefaction analyses indicated that the majority of spider species were readily detectable using pitfall traps and inventoried during this study (111 found and 168 estimated to be present). Simpson’s Diversity measure bootstrap estimates determined species diversity overall to be very diverse (0.966), as did a Shannon Weiner Diversity bootstrap estimate (5.483). Also, Simpson’s measure of species evenness (0.264) indicated a low species evenness. Those species found in only one habitat comprised 50% of the total species, and their densities ranged from 1-5 individuals. Those species found in just two habitats comprised 25% of the total species, and their densities ranged from 2-21 individuals. Species found in all three habitats comprised the remaining 25%, and their densities ranged from 4-53 individuals found. Most species occurred at low densities in this study and this often precluded conducting more detailed analyses. Additional sampling is expected to, first, detect known species occurring in previously unrecorded habitats and, second, to detect species not previously found in the park. This inventory of spiders at Lick Creek will provide a basis for further studies on biodiversity and the assessment of human impact on the environment.
5

Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas

Henderson, Takesha Yvonne 02 June 2009 (has links)
Lick Creek Park is a 515 acre nature park that was acquired in 1987 by the City of College Station, Texas. The site has a variety of indigenous plant and animal species and is an important natural resource for citizens of the region. There is a long-term commitment to inventory this natural park to monitor the changes as our urban community expands to surround the park. There are 989 species of spiders currently recorded from Texas and 332 of them are known to occur in Brazos County. My focus was on improving the ground spider inventory at Lick Creek Park. Spider collections were made using 18 regularly-sampled pitfall traps distributed evenly among three habitats. Spiders from 24 families, 66 genera, and 111 species were identified from 918 specimens, including 627 immature and 291 adult spiders, captured in pitfall traps from April 2005-April 2006. Of the 111 species found, 45 were represented by one specimen only and 20 were represented by two specimens. Rarefaction analyses indicated that the majority of spider species were readily detectable using pitfall traps and inventoried during this study (111 found and 168 estimated to be present). Simpson’s Diversity measure bootstrap estimates determined species diversity overall to be very diverse (0.966), as did a Shannon Weiner Diversity bootstrap estimate (5.483). Also, Simpson’s measure of species evenness (0.264) indicated a low species evenness. Those species found in only one habitat comprised 50% of the total species, and their densities ranged from 1-5 individuals. Those species found in just two habitats comprised 25% of the total species, and their densities ranged from 2-21 individuals. Species found in all three habitats comprised the remaining 25%, and their densities ranged from 4-53 individuals found. Most species occurred at low densities in this study and this often precluded conducting more detailed analyses. Additional sampling is expected to, first, detect known species occurring in previously unrecorded habitats and, second, to detect species not previously found in the park. This inventory of spiders at Lick Creek will provide a basis for further studies on biodiversity and the assessment of human impact on the environment.
6

Production and characterization of a synthetic spider silk protein based on the Argiope aurantia MaSp2 sequence

Brooks, Amanda E. January 2006 (has links)
Thesis (Ph. D.)--University of Wyoming, 2006. / Title from PDF title page (viewed on June 26, 2008). Includes bibliographical references.
7

The Spider Mites of Arizona (Acarina: Tetranychidae)

Tuttle, Donald M., Baker, Edward W. 04 1900 (has links)
No description available.
8

Characterizing Transient Regime Multi-frequency Raman Generation by the Aid of Spectral Phase Interferometry for Direct Electric-field Reconstruction

Yan, Hao 05 September 2013 (has links)
Multi-frequency Raman Generation (MRG) has been achieved in the transient regime excited by dual-wavelength chirped pump pulses. Spectral phase interferometry for direct electric-field reconstruction (SPIDER) technique is used to study the group velocity dispersion (GVD) of MRG. A few changes have been applied to the SPIDER set-up to adapt it to the multi-color but narrow-bandwidth pulses. The phase of orders from the 1st Stokes order through to the 1st anti-Stokes order are measured. The technique is applied on the study of phase dependency of the 1st anti-Stokes orders on frequency tuning through the Raman transition.
9

Cladistic analysis of Macrobunidae Petrunkevitch, 1928 new rank and revision of Macrobuninae (Araneae). / Análise cladística de Macrobunidae Petrunkevitch 1928 stat. nov. e revisão de Macrobuninae (Araneae)

Almeida-Silva, Lina Maria 26 August 2013 (has links)
Macrobuninae Petrunkevitch is revised and submitted to a cladistic analysis. Macrobuninae, once considered the biggest Amaurobiidae Thorell subfamily is now proved to be not even closely related to Amaurobiinae, the \"true amaurobiids\". Our matrix, composed by 82 terminal taxa and 107 characters, includes representatives of all Macrobuninae genera and new taxa we believed to be part of Macrobuninae. As out-groups, we included representatives of the families Agelenidae Koch, Amaurobiidae, Amphinectidae Forster & Wilton, Chummidae Jocqué, Desidae Pocock, Dictynidae O. P.-Cambridge, Phyxelididae Lehtinen, Stiphidiidae Dalmas, Tengellidae Dahl, Titanoecidae Lehtinen, Zorocratidae Dahl and Zoropsidae Bertkau, which were suggested as related to Macrobuninae by previous studies. Our main results confirm Macrobuninae as not forming a monophyletic group with Amaurobiidae and shows the need to erect Macrobunidae Petrunkevitch, 1928 new rank to include Macrobuninae and relatives. Three other subfamilies are proposed here: Retirinae subfam. nov., Pakehinae subfam. nov., and Zanomyinae Ubick, 2005 new rank. Chummidae, currently composed by one genus and two species, is considered a junior-synonym with Macrobunidae. Amaurobiidae appears as sister group of the \"Oval Calamistrum Clade\" and the \"Fused Paracribellar clade\". The subfamily Macrobuninae is revised at the generic-level and redelimited to include a total of 26 genera. Of those, thirteen are newly described: Siyabonga gen. nov., Peckmaria gen. nov., Ijoubetumsam gen. nov., Imbumbulu gen. nov., Ibhulashi gen. nov., Umunwe gen. nov., Pigozzoi gen. nov., Samadhia gen. nov., Naynay gen. nov., Segoko gen. nov., Deusemais gen. nov., Madiba gen. nov. and Ushaka gen nov.. The remaining known genera are redescribed including their type-species, except the ones with recent, up to date descriptions. Seventeen new species are described: Emmenomma joshuabelli sp. nov., Macrobunus alejandrosanzi, sp. nov., Macrobunus eniomattosi sp. nov., Yupanquia lenktaitisi sp. nov., Ijoubetumsam frizzellae sp. nov., Deusemais viximaria sp. nov., Naynay meikleae sp. nov., Pigozzoi pifozonho sp. nov., Samadhia kellyfujiharae sp. nov., Siyabonga kakhulu sp. nov., Imbumbulu westhuizenis sp. nov., Madiba haddadi sp. nov., Ushaka umsila sp. nov., Ushaka philai sp. nov., Ibhulashi lakeside sp. nov., Umunwe ndabae sp. nov. and Segoko chueneorum sp. nov. Eight genera removed from Macrobuninae are assigned to other subfamilies and/or families. All taxonomic changes are justified by the phylogenetic analysis. For the first time the male specimens of Hicanodon Tullgren, Yupanquia Lehtinen and Chresiona Simon are described; Anisacate fuegianum bransfield Usher is raised to the species level, A. bransfield Usher new rank; Emmenomma beauchenicum Usher is considered junior synonym of E. oculatum Simon; Emmenomma oculatum obscurum Simon is removed from the synonym with E. oculatum and raised to the species level, Emmenomma obscurum Simon new rank. The type specimens of Macrobunus backhauseni (Simon) are considered non co-specifics and a new species Macrobunus alejandrosanzi sp. nov. is described based on the female. The true female of M. backhauseni is described for the first time. Other taxonomic changes include: removal of Notolathys Mello-Leitão from synonymy with Auximella Strand and placement as a junior synonym of Retiro Mello-Leitão; to consider Urepus Roth a junior synonym of Auximella; and Tymbira Mello-Leitão a junior synonym of Metaltella Mello-Leitão / Macrobuninae é alvo de uma revisão e análise cladística. Esta subfamília, que já foi considerada a maior de Amaurobiidae, mostra-se pouco relacionada aos Amaurobiinae ou \"amaurobiideos verdadeiros\". A matriz deste estudo, composta por 82 taxa terminais e 107 caracteres inclui representantes de todos os gêneros de Macrobuninae e novos taxa desta subfamília. Como grupo-externo, foram utilizados representantes de: Agelenidae Koch, Amaurobiidae, Amphinectidae Forster & Wilton, Chummidae Jocqué, Desidae Pocock, Dictynidae O. P.-Cambridge, Phyxelididae Lehtinen, Stiphidiidae Dalmas, Tengellidae Dahl, Titanoecidae Lehtinen, Zorocratidae Dahl e Zoropsidae Bertkau, uma vez que estas famílias foram relacionadas a Macrobuninae em outros estudos. Os resultados principais confirmam que Macrobuninae não está intimamente relacionada a Amaurobiidae e confirma a necessidade de elevar Macrobuninae à categoria de família, Macrobunidae Petrunckevitch, 1928 status nov. a fim de incluir os Macrobuninae e generos relacionados. Três subfamílias aqui descritas: Retirinae subfam. nov., Pakehinae subfam. nov., and Zanomyinae Ubick, 2005 status nov.. Chummidae Jocqué, atualmente composta por um gênero e duas espécies, passa a ser considerada sinônimo-junior de Macrobunidae. Amaurobiidae aparece como grupo-irmão dos clados \"paracribellares fundidas\" e calamistro oval. A subfamília Macrobuninae é revisada em nível genérico e redelimitada a fim de incluir um total de 26 gêneros. Destes, treze gêneros novos são descritos: Siyabonga gen . nov., Peckmaria gen. nov., Ijoubetumsam gen. nov., Imbumbulu gen. nov., Ibhulashi gen. nov., Umunwe gen. nov., Pigozzoi gen. nov., Samadhia gen. nov., Naynay gen. nov., Segoko gen. nov., Deusemais gen. nov., Madiba gen. nov. and Ushaka gen nov.. Dos treze gêneros conhecidos, apenas os que possuem descriçoões recentes e atualizadas não tiveram suas espécies-tipo redescritas. Dezessete espécies novas são descritas: Emmenomma joshuabelli sp. nov., Macrobunus alejandrosanzi, sp. nov., Macrobunus eniomattosi sp. nov., Yupanquia lenktaitisi sp. nov., Ijoubetumsam frizzellae sp. nov., Deusemais viximaria sp. nov., Naynay meikleae sp. nov., Pigozzoi pifozonho sp. nov., Samadhia kellyfujiharae sp. nov., Siyabonga kakhulu sp. nov., Imbumbulu westhuizenis sp. nov., Madiba haddadi sp. nov., Ushaka umsila sp. nov., Ushaka philai sp. nov., Ibhulashi lakeside sp. nov., Umunwe ndabae sp. nov. e Segoko chueneorum sp. nov.. Oito gêneros são removidos de Macrobuninae e transferidos para outras subfamílias e/ou famílias. As mudanças taxonômicas apresentadas são corroboradas pela análise cladística. São apresentadas as primeiras descrições de machos de espécies de Hicanodon Tullgren, Yupanquia Lehtinen e Chresiona Simon. Anisacate fuegianum bransfield Usher é elevada a categoria de espécie, A. bransfield Usher stat. nov.. Emmenomma beauchenicum Usher é considerada sinônimo junior de E. oculatum. Emmenomma oculatum obscurum Simon é removida da sinonímia e elevada a categoria de espécie, Emmenomma obscurum Simon stat. nov.. Os espécimes-tipo de M. backhauseni são aqui considerados duas espécies diferentes e com base na fêmea uma espécie nova M. alejandrosanzi sp. nov. é descrita. A verdadeira fêmea de M. backhauseni (Simon) é descrita pela primeira vez. Outras mudanças taxonômicas proveniente do estudo dos espécimes-tipo incluem remover Notolathys Mello-Leitão da sinonímia com Auximella Strand e transferir Notolathys para sinônimo-junior de Retiro Mello-Leitão; sinonimizar Urepus Roth e Auximella; considerar Tymbira Mello-Leitão sinônimo-junior de Metaltella Mello-Leitão
10

Chromosomal Evolution of Delena cancerides

Sharp, Hayley Evette, Hayley.Sharp@latrobe.edu.au January 2009 (has links)
Chromosomal evolution has long been linked with the process of organismal speciation, and many different theories have been suggested over the years to explain why this would be so. These theories can be loosely grouped into two eras. Classical chromosomal speciation models focused on negative heterosis of chromosomal rearrangements causing malsegregation and germ cell death in hybrids. More recent models examine the effects of reduced recombination around rearrangements and the impact this can have on sequence evolution, specifically the accumulation of genetic incompatibilities.¶ The huntsman spider Delena cancerides is known to be highly chromosomally variable, and to have reduced recombination near fusions. However, this species has previously only been interpreted with reference to the classical models of chromosomal speciation, the expectations of which it does not fit well. Broad-scale sampling of this spider has revealed extensive chromosomal diversity and complexity. Twenty one chromosomally differentiated populations (karyomorphs) of this spider have now been described, including those with the putatively ancestral configuration of all telocentric bivalents at meiosis (tII), and many that are saturated for Robertsonian fusions. These include up to six different karyomorphs with metacentric bivalents (mII), eight karyomorphs that form a chain of chromosomes at male meiosis, and six karyomorphs that form two separate but co-segregating chains.¶ A computer simulation was used to test hypotheses regarding the evolution of this chromosomal diversity, which indicated that fusions are likely to have accumulated gradually, possibly due to meiotic drive. Historical phylogeographic analyses have shown that deep cryptic divisions exist which are concordant with the chromosomal diversity.¶ Hybridization experiments have suggested that many hybrid zones between karyomorphs of this species are tension zones, and that genetic incompatibilities are likely to play an important role in generating partial reproductive isolation of karyomorphs. Furthermore, several hybrid zones appear to have been modified by staggered clines. The staggering of clines is thought to ameliorate reproductive isolation mechanisms that are dependent on epistatic fitness interactions, and so may prevent diverging populations progressing towards speciation. ¶Therefore, on the basis of the available evidence, D. cancerides may fit the recombination suppression model of chromosomal speciation, although it may be unlikely that the karyomorphs will progress towards full species status. Hence, this species may in the future make a highly informative model organism for investigating the early stages of genetic reproductive isolation associated with chromosomal rearrangements.

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