Self-organizing propagation patterns from dynamic self-assembly in monolayers

Propagation of localized orientational waves, as imaged by Brewster angle microscopy, is induced by low intensity linearly polarized light inside axisymmetric smectic-C confined domains in a photosensitive molecular thin film at the air/water interface (Langmuir monolayer). Results from numerical simulations of a model that couples photoreorientational effects and long-range elastic forces are presented. Differences are stressed between our scenario and the paradigmatic wave phenomena in excitable chemical media.

Self-organizing propagation patterns from dynamic self-assembly in monolayers

Propagation of localized orientational waves, as imaged by Brewster angle microscopy, is induced by low intensity linearly polarized light inside axisymmetric smectic-C confined domains in a photosensitive molecular thin film at the air/water interface (Langmuir monolayer). Results from numerical simulations of a model that couples photoreorientational effects and long-range elastic forces are presented. Differences are stressed between our scenario and the paradigmatic wave phenomena in excitable chemical media.

Ultra high throughput sequencing excludes MDH1 as candidate gene for RP28-linked retinitis pigmentosa.

PURPOSE: Mutations in IDH3B, an enzyme participating in the Krebs cycle, have recently been found to cause autosomal recessive retinitis pigmentosa (arRP). The MDH1 gene maps within the RP28 arRP linkage interval and encodes cytoplasmic malate dehydrogenase, an enzyme functionally related to IDH3B. As a proof of concept for candidate gene screening to be routinely performed by ultra high throughput sequencing (UHTs), we analyzed MDH1 in a patient from each of the two families described so far to show linkage between arRP and RP28. METHODS: With genomic long-range PCR, we amplified all introns and exons of the MDH1 gene (23.4 kb). PCR products were then sequenced by short-read UHTs with no further processing. Computer-based mapping of the reads and mutation detection were performed by three independent software packages. RESULTS: Despite the intrinsic complexity of human genome sequences, reads were easily mapped and analyzed, and all algorithms used provided the same results. The two patients were homozygous for all DNA variants identified in the region, which confirms previous linkage and homozygosity mapping results, but had different haplotypes, indicating genetic or allelic heterogeneity. None of the DNA changes detected could be associated with the disease. CONCLUSIONS: The MDH1 gene is not the cause of RP28-linked arRP. Our experimental strategy shows that long-range genomic PCR followed by UHTs provides an excellent system to perform a thorough screening of candidate genes for hereditary retinal degeneration.

Estimating the confidence level of white matter connections obtained with MRI tractography.

BACKGROUND: Since the emergence of diffusion tensor imaging, a lot of work has been done to better understand the properties of diffusion MRI tractography. However, the validation of the reconstructed fiber connections remains problematic in many respects. For example, it is difficult to assess whether a connection is the result of the diffusion coherence contrast itself or the simple result of other uncontrolled parameters like for example: noise, brain geometry and algorithmic characteristics. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we propose a method to estimate the respective contributions of diffusion coherence versus other effects to a tractography result by comparing data sets with and without diffusion coherence contrast. We use this methodology to assign a confidence level to every gray matter to gray matter connection and add this new information directly in the connectivity matrix. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that whereas we can have a strong confidence in mid- and long-range connections obtained by a tractography experiment, it is difficult to distinguish between short connections traced due to diffusion coherence contrast from those produced by chance due to the other uncontrolled factors of the tractography methodology.

Development of a Durability Test for Asphalts, May 1972

Research Project HR-124, "Development of a Laboratory Durability Test for Asphalts," was initiated in 1966 as a long-range comprehensive program. Its ultimate objective was to develop a simple, rapid laboratory test that could be used by highway engineers to select paving asphalt according to quality, to identify inferior asphalts, and to reasonably predict the useful life of asphalts once they were incorporated in the pavements.

Geohydrology of Muscatine Island, Muscatine County, Iowa, 1977

The availability of large quantities of high-quality ground water from the Muscatine Island aquifer has had a tremendous impact upon urban, industrial and agricultural development of this part of Iowa. Although the nonpumping level of water has been lowered significantly near major pumping centers through time, proper management of this water resource can assure a continued supply of water for all competing users. This report provides basic information for long range management. Fold out maps are included.

Actin cables and the exocyst form two independent morphogenesis pathways in the fission yeast.

Cell morphogenesis depends on polarized exocytosis. One widely held model posits that long-range transport and exocyst-dependent tethering of exocytic vesicles at the plasma membrane sequentially drive this process. Here, we describe that disruption of either actin-based long-range transport and microtubules or the exocyst did not abolish polarized growth in rod-shaped fission yeast cells. However, disruption of both actin cables and exocyst led to isotropic growth. Exocytic vesicles localized to cell tips in single mutants but were dispersed in double mutants. In contrast, a marker for active Cdc42, a major polarity landmark, localized to discreet cortical sites even in double mutants. Localization and photobleaching studies show that the exocyst subunits Sec6 and Sec8 localize to cell tips largely independently of the actin cytoskeleton, but in a cdc42 and phospholipid phosphatidylinositol 4,5-bisphosphate (PIP₂)-dependent manner. Thus in fission yeast long-range cytoskeletal transport and PIP₂-dependent exocyst represent parallel morphogenetic modules downstream of Cdc42, raising the possibility of similar mechanisms in other cell types.

Blue luminescence at room temperature in defective MgO films

Luminescence spectroscopy has been used to characterize MgO films prepared by rf-sputtering. A clear correlation is found between the appearance of an emission peak centered at approximately 460 nm and the detection of ferromagnetic ordering in the samples. We suggest that cationic vacancies are responsible for the blue-light emission by introducing p states into the electronic band-gap. In accordance with this, our results strongly indicate that cationic vacancies are at the heart of the appearance of long-range magnetic ordering in MgO films.

CIRAS News Annual Report 2000, January 3, 2001

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.

CIRAS News Annual Report 2001, January 3, 2001

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.

CIRAS News Annual Report 2002, January 3, 2001

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.

CIRAS News Annual Report 2003, January 5, 2004

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.

CIRAS News Annual Report 2004, November 29, 2004

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.

CIRAS News Annual Report 2005, October 21, 2005

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.

CIRAS News Annual Report 2006, September 4, 2007

CIRAS professionals, the equipment they use to do their jobs, and the latest in technical support equipment. With these investments, CIRAS continues to meet the needs of Iowa manufacturers, whether in doing routine problem solving, long-range planning, or transferring newer technologies. In all of its services, but most notably in product development projects, one of the strengths of CIRAS lies in bringing ISU students into the picture, both to help reach project goals and as real-job learning experiences for the students.