14,270 research outputs found
Weedy adaptation in Setaria spp.: IX. Effects of salinity, temperature, light and seed dormancy on Setaria faberi seed germination
Life in salty habitats is a function of tolerance to those chemicals at all
critical phases of a plant's life history. The ability to withstand salt as an
established plant may require different mechanisms and plant traits than those
needed to germinate in salty soils. Seeds establishing themselves in high salt
content may respond differently depending on the light conditions and seed
germinability at the time of salty water imbibition. S. faberi seed (and S.
viridis and S. pumila) plants were discovered thriving along the seacoasts of
Southern Japan. These plants possess the ability to after-ripen, germinate,
emerge and establish themselves, grow and reproduce in the salty soils and
salt-laden atmospheres present in these windy habitats. The objectives of this
paper are to determine the effect of salt (NaCl) in water imbibed by S. faberi
seed during after-ripening and germination, as well temperature and light.
Observations made also provide insights on the possible relationship between
salt and drought tolerance. Seed germination of all phenotypes inhibited by two
percent or more of NaCl. The effects of lesser amounts of NaCl on each of the
three phenotypes was highly dependent on the specific temperature and light
conditions. The three test phenotypes provided a good range to detect responses
to salinity, allowing the observation of both stimulatory and inhibitory
responses.Comment: 11 pages, 1 tabl
\u27Art\u27 They Can\u27t See, Lines, Anatomy of Decomposing, October on Danford Creek, Wing Bone, and Taxidermy
The following document includes a selection and submission for the Hilltop Review. Within the file the reader will find five (5) poems and one (1) micro fiction piece. The poems are titled \u27Art\u27 They Can\u27t See, Lines, Anatomy of Decomposing, October on Danford Creek, and Wing Bone. These poems incorporate darkness, illness, social issues, and a manifestation and exploration of the human condition. The Microfiction text titled Taxidermy, details the interaction between two siblings showcasing the younger sister\u27s mental illness by detailing the delusional and obsessive behavior of this character.
These texts have been workshopped under the instruction of poets, William Olsen & Nancy Eimers and Fiction writer, Thisbe Nissen at Western Michigan University
The Electromigration Force in Metallic Bulk
The voltage induced driving force on a migrating atom in a metallic system is
discussed in the perspective of the Hellmann-Feynman force concept, local
screening concepts and the linear-response approach. Since the force operator
is well defined in quantum mechanics it appears to be only confusing to refer
to the Hellmann-Feynman theorem in the context of electromigration. Local
screening concepts are shown to be mainly of historical value. The physics
involved is completely represented in ab initio local density treatments of
dilute alloys and the implementation does not require additional precautions
about screening, being typical for jellium treatments. The linear-response
approach is shown to be a reliable guide in deciding about the two
contributions to the driving force, the direct force and the wind force.
Results are given for the wind valence for electromigration in a number of FCC
and BCC metals, calculated using an {\it ab initio} KKR-Green's function
description of a dilute alloy.Comment: 14 pages, 1 Postscript figur
Low energy ion bombardment on c-Ge surfaces
Amorphous germanium thin films (25–60 Å) were prepared by low energy (500, 800 eV) bombardment of noble gas ions (Ne, Ar, Kr) on c-Ge(001). The films were examined by spectroscopic ellipsometry and analysed using linear regression analysis (LRA). The most probable composition of the damaged toplayer is that of void free amorphous germanium, comparable with those obtained by dc-magnetron sputtering. The results are in excellent agreement with Monte Carlo simulations of the transport of ions in matter (TRIM86)
Ultrafast all-optical wavelength conversion in silicon-insulator waveguides by means of cross phase modulation using 300 femtosecond pulses
In this paper we report the ultrafast all-optical wavelength conversion in Silicon-on-Insulator (SOI) waveguides. We used a pump-probe setup with 300 femtosecond pulses to demonstrate large temporal phase-shifts, caused by the Kerr effect and free carrier generation. Large wavelength shifts of a 1683nm probe signal have been observed. The wavelength conversion, ranging from 10nm redshifts to 15nm blueshifts, depending on the time delay between the pump and probe pulses, is caused by the pump induced Cross Phase Modulation. Furthermore, an all-optical switching scheme using SOI microring resonators is discussed. These results enable ultrafast all-optical switching using SOI microring resonators
Scanning Tunneling Spectroscopy of Suspended Single-Wall Carbon Nanotubes
We have performed low-temperature STM measurements on single-wall carbon
nanotubes that are freely suspended over a trench. The nanotubes were grown by
CVD on a Pt substrate with predefined trenches etched into it. Atomic
resolution was obtained on the freestanding portions of the nanotubes.
Spatially resolved spectroscopy on the suspended portion of both metallic and
semiconducting nanotubes was also achieved, showing a Coulomb-staircase
behavior superimposed on the local density of states. The spacing of the
Coulomb blockade peaks changed with tip position reflecting a changing tip-tube
capacitance
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