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Seasonal patterns in the productivity of a giant kelp (Macrocystis pyrifera) forest the effect of nutrient availability /Zimmerman, Richard Carl. January 1983 (has links)
Thesis (Ph. D.)--University of Southern California, 1983. / Includes bibliographical references (leaves 164-182).
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Evolutionary genetics of barramundi (Lates calcarifer) in the Australian regionMarshall, Carina Rynn Ecremen. January 2005 (has links)
Thesis (Ph. D.)--Murdoch University, 2005. / Title from PDF title page (viewed on Sept. 24, 2005). Includes bibliographical references (p. 104-120).
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Demography, biomass production and effects of harvesting giant kelp Macrocystis pyrifera (Linnaeus) in southern New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology at the University of Canterbury, New Zealand /Pirker, John G. January 2002 (has links)
Thesis (Ph. D.)--University of Canterbury, 2002. / Typescript (photocopy). Includes bibliographical references (leaves [210]-225). Also available via the World Wide Web.
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A study of polytene chromosomes in suspensor cells of some leguminous plants /Freed, Heather Joy. January 1974 (has links)
No description available.
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Heavy element enrichment of the gas giant planetsCoffey, Jaime Lee 11 1900 (has links)
According to both spectroscopic measurements and interior models, Jupiter,
Saturn, Uranus and Neptune possess gaseous envelopes that are enriched in
heavy elements compared to the Sun. Straightforward application of the
dominant theories of gas giant formation - core accretion and gravitational
instability - fail to provide the observed enrichment, suggesting that the
surplus heavy elements were somehow dumped onto the planets after the
envelopes were already in existence.
Previous work has shown that if giant planets rapidly reached their cur
rent configuration and radii, they do not accrete the remaining planetesimals
efficiently enough to explain their observed heavy-element surplus. We ex
plore the likely scenario that the effective accretion cross-sections of the
giants were enhanced by the presence of the massive circumplanetary disks
out of which their regular satellite systems formed. Perhaps surprisingly,
we find that a simple model with protosatellite disks around Jupiter and
Saturn can meet known constraints without tuning any parameters. Fur
thermore, we show that the heavy-element budgets in Jupiter and Saturn
can be matched slightly better if Saturn’s envelope (and disk) are formed
roughly 0.1 — 10 Myr after that of Jupiter.
We also show that giant planets forming in an initially-compact con
figuration can acquire the observed enrichments if they are surrounded by
similar protosatellite disks.
Protosatellite disks efficiently increase the capture cross-section, and thus
the metallicity, of the giant planets. Detailed models of planet formation
must therefore account for the presence of such disks during the early stages
of solar system formation.
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Giant resonance study by 6li scatteringChen, Xinfeng 15 May 2009 (has links)
Nuclear incompressibility Knm is an important parameter in the nuclear matter equation
of state (EOS). The locations of the isocalar giant monopole resonance (ISGMR) and
giant dipole resonance (ISGDR) of nuclei are directly related to Knm and thus can give
the most effective constraint on the value of the Knm. In order to determine Knm
accurately, a systematic study of the ISGMR and ISGDR over a wide range of nuclei is
necessary. Alpha inelastic scattering at small angles has been successfully used to study
the ISGMR of heavy and medium nuclei where the monopole resonance is concentrated
in a broad peak. For light nuclei (A<40), however, ISGMR strengths are more elusive
because the resonance is fragmented and extends to excitation energies above 35 MeV.
Other processes give a large physical background at high excitation energy in α inelastic
scattering, which makes it difficult to extract strength distributions in this range. As an
isoscalar projectile (N=Z), 6Li scattering could be an alternate way to study giant
resonances. A better ratio between the resonance peak and the continuum is expected in
6Li scattering due to the low particle emitting threshold. Another important motivation
for 6Li scattering study is to explore the possibility of expanding current research from
stable nuclei to radioactive nuclei with inverse reactions using 6Li as a target.
Data for elastic scattering of 240 MeV 6Li ions and inelastic scattering to low-lying states
and giant resonances was taken for 24Mg, 28Si and 116Sn. A data analysis procedure was
developed for double folding calculations. The optical potential parameters for 6Li + 24Mg, 6Li + 28Si and 6Li + 116Sn scattering systems were obtained by fitting elastic
scattering data. Multipole analyses were carried out for inelastic scattering to high lying
isoscalar giant resonances with multipolarities L=0 - 3. The results for the ISGMR and
ISGQR are in agreement with those obtained with 240 MeV α scattering, however the
agreement for the ISGDR and HEOR is not so good, indicating the uncertainty in
extracting these strengths. This work has shown that 240 MeV 6Li scattering is a viable
way to study the ISGMR and ISGQR and can be particularly useful in rare isotope
studies where 6Li can be used as the target.
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A CASE OF UNILATERAL GIANT HYDRONEPHROSIS WITH RENAL INSUFFICIENCYMIYAKE, KOJI, HIBI, HATSUKI, YAMAMOTO, MASANORI 25 December 1995 (has links)
No description available.
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Techniques for studying the nuclear condition of giant cells induced by Meloidogyne speciesHe, Bin 12 April 2006 (has links)
Nematodes of the genus Meloidogyne are known as Âroot-knot nematodes due
to the characteristic knots or galls found on the roots of infected plants. Root-knot
nematodes attack over 2000 species of plants and cause over 80 billion dollars lost
annually. Giant cells are feeding sites of root-knot nematodes and are enlarged
multinuclear cells induced by the nematodes in susceptible host roots and that function
to provide nutrients to the nematode. This thesis presents data on two techniques of
studying the nuclear condition in giant cells. Colchicine was used to arrest mitosis in
giant cells in a previous study. Here we test the effect of colchicine on nematode
activity. The results showed that colchicine did not affect nematode egg hatch, juvenile
activity, or hatch of eggs produced by treated juveniles. These results confirm that
colchicine can be used to arrest mitosis in giant cells without affecting the nematode
parasite.
A major obstacle to the study of giant cells is collecting tissue samples that are
specific to giant cells. Laser capture microdissection (LCM) is a technique that allows
one to sample a single giant cell. A focused laser beam was used to collect samples of
giant cell cytoplasm from fixed and sectioned tissues. RNA was then extracted from
those isolated samples. Using three tomato genes as test samples, specific primers were
designed to measure expression level of Rb7, LHA4, and HXK1 gene by Real-Time PCR.
Expression of LHA4 and Rb7 increased with time after inoculation, and immature giant
cells reached levels that were 3 and 6 times, respectively, that of cortical cells, but which
were not different from root meristem cells. Expression of HXK1 did not change with
time after inoculation and has the same level of that in root tip and cortical tissues.
These data confirmed that the techniques of LCM coupled with RT-real-time PCR can
be used to quantitate expression of genes at different stages of giant cell development
without contamination from surrounding cells.
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19 |
Histological and histochemical studies of muscle types and their innervation in Achatina fulica (Bowdich).Pan, Da-chuan, January 1974 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1975. / Typewritten.
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Heavy element enrichment of the gas giant planetsCoffey, Jaime Lee 11 1900 (has links)
According to both spectroscopic measurements and interior models, Jupiter,
Saturn, Uranus and Neptune possess gaseous envelopes that are enriched in
heavy elements compared to the Sun. Straightforward application of the
dominant theories of gas giant formation - core accretion and gravitational
instability - fail to provide the observed enrichment, suggesting that the
surplus heavy elements were somehow dumped onto the planets after the
envelopes were already in existence.
Previous work has shown that if giant planets rapidly reached their cur
rent configuration and radii, they do not accrete the remaining planetesimals
efficiently enough to explain their observed heavy-element surplus. We ex
plore the likely scenario that the effective accretion cross-sections of the
giants were enhanced by the presence of the massive circumplanetary disks
out of which their regular satellite systems formed. Perhaps surprisingly,
we find that a simple model with protosatellite disks around Jupiter and
Saturn can meet known constraints without tuning any parameters. Fur
thermore, we show that the heavy-element budgets in Jupiter and Saturn
can be matched slightly better if Saturn’s envelope (and disk) are formed
roughly 0.1 — 10 Myr after that of Jupiter.
We also show that giant planets forming in an initially-compact con
figuration can acquire the observed enrichments if they are surrounded by
similar protosatellite disks.
Protosatellite disks efficiently increase the capture cross-section, and thus
the metallicity, of the giant planets. Detailed models of planet formation
must therefore account for the presence of such disks during the early stages
of solar system formation.
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