Physical Sciences and Mathematics Commons^™

The Biosynthetic Gene Cluster For The Anticancer Drug Bleomycin From Streptomyces Verticillus Atcc15003 As A Model For Hybrid Peptide–Polyketide Natural Product Biosynthesis, B. Shen, Liangcheng Du, C. Sanchez, D. J. Edwards, M. Chen, J. M. Murrell

Liangcheng Du Publications

The hybrid peptide–polyketide backbone of bleomycin (BLM) is assembled by the BLM megasynthetase that consists of both nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) modules. BlmIX/BlmVIII/BlmVII constitute a natural hybrid NRPS/PKS/NRPS system, serving as a model for both hybrid NRPS/PKS and PKS/NRPS systems. Sequence analysis and functional comparison of domains and modules of BlmIX/BlmVIII/BlmVII with those of nonhybrid NRPS and PKS systems suggest that (1) the same catalytic sites appear to be conserved in both hybrid NRPS–PKS and nonhybrid NRPS or PKS systems, with the exception of the KS domains in the hybrid NRPS/PKS systems that are unique; (2) …

The Prairie Naturalist Volume 33, No.4 December 2001

The Prairie Naturalist

SPECIES, SEASON, AND DENSITY OF BURIED SEEDS SURVIVING FOX SQUIRREL DEPREDATION ▪ C. C. Smith, and J. M. Briggs

RELATI0NSHIP OF HYDROLOGICAL CONDITIONS AND POPULATlONS OF BREEDING PIPING PLOVERS ▪ D. S. Licht,

DEMODICOSIS IN A WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) IN SOUTH DAKOTA ▪ C. N. Jacques, J. A Jenks. M. B. Hildreth. R. J. Schauer, and D. D. Johnson

SURVEYS OF CALLING AMPHIBIANS IN NORTH DAKOTA ▪ D. H. Johnson, and R. D. Batie

EFFECTS OF HUMAN PRESENCE ON VOCALIZATIONS OF GRASSLAND BIRDS IN KANSAS ▪ S. L Bye, R. J. Robel, and K. E. Kemp

Reviewers 2001

Author …

Water Current, Volume 33, No. 6. December 2001

Water Current Newsletter

• “Daisy Well System” Promising Way for Small Communities to Fight Nitrates by Steve Ress

• From the Director

• Meet the Faculty

• Water and the NRCS…All Encompassing Topics by Steve Chick

• Variety and Current Issues Punctuate Spring Water and Natural Resources Seminar by Steve Ress

• Integrated Water Management Options in the Nebraska Ground Water Management & Protection Act by J. David Aiken

• Arkansas Researchers Study Water Quality on Nebraska Tribal Lands by Ralph Davis and Shelley McGinnis

• Platte River Policy Preferences by Raymond J. Supalla

• Water News Briefs

Large Sets Of Zero Analytic Capacity, John Garnett, Stan T. Yoshinobu

Mathematics

We prove that certain Cantor sets with non-sigma-finite one-dimensional Hausdorff measure have zero analytic capacity.

Seafloor Characterization From Spatial Variation Of Multibeam Backscatter Vs. Grazing Angle, Tianhang Hou, Lloyd C. Huff, Yuri Rzhanov, Larry A. Mayer

Center for Coastal and Ocean Mapping

Backscatter vs. grazing angle, which can be extracted from multibeam backscatter data, depend on characteristics of the multibeam system and the angular responses of backscatter that are characteristic of different seafloor properties, such as sediment hardness and roughness. Changes in backscatter vs. grazing angle that are contributed by the multibeam system normally remain fixed over both space and time. Therefore, they can readily be determined and removed from backscatter data. The variation of backscatter vs. grazing angle due to the properties of sediments will vary from location to location, as sediment type changes. The sediment component of variability can be …

Improvement To The International Bathymetric Chart Of The Arctic Ocean (Ibcao): Updating The Data Base And The Grid Model, Martin Jakobsson, Norman Cherkis

Center for Coastal and Ocean Mapping

The project to develop the IBCAO grid model was initiated in 1997 with the objective of providing to the Arctic research community an improved portrayal of the seabed north of 64-deg N, in a form suitable for digital manipulation and visualization. The model was constructed from a compilation of all single-beam and multibeam echo soundings that were available for the polar region, complemented where appropriate by newly released contour information. The grid features a cell size of 2.5 x 2.5 km on a polar stereographic projection; it is constructed on the WGS 84 datum, with true scale at 75-deg N. …

1998 Debris Flows Near The Yakima River, Kittitas County, Washington—Some Geomorphic Implications, Martin R. Kaatz

Geography Faculty Scholarship

The geomorphic consequences of debris flows and their asso- ciated storms have been documented in many parts of the United States. Few, if any, have been studied and documented in central Washington. The importance of recurrent debris flows in sculpting Washington landscapes has not been generally recognized compared to other processes. Arid and semi-arid regions are particularly vulnerable to debris flows triggered by sudden intense thunderstorms. Most such areas are sparsely populated and eyewitnesses are uncommon. By contrast, semi-arid central Washington is relatively well popu- lated, and there are likely to be people who have observed the storms. Such witnesses …

Methanesulfonate In The Firn Of King George Island, Antarctica, Jiankang Han, Zichu Xie, Xinping Zhang, Dongsheng Dai, Paul Andrew Mayewski, M. S. Twickler

Earth Science Faculty Scholarship

Methanesulfonate was investigated as a potential contributor to the sulfur budget, based on analysis of a firn core from Collins Ice Cap, King George Island, Antarctica (62°10' S, 58°50' W). The anion was found to be present at a mean concentration of 0.17 μeq L^-1, with a maximum of 0.73 μeq L^-1. Dating based on the δ¹⁸O profile suggests that the principal peaks of methanesulfonate are associated with snow deposited in summer and autumn. A careful examination of MSA, SO₄^2-and nssSO₄^2- profiles indicates that two of the three peaks …

Potential Runoff Accumulation In Wheatbelt Towns Of Western Australia, Mahtab Ali, Travis Cattlin, Neil Coles, Sharam Sharafi

Resource management technical reports

Describes an analysis of flood runoff volumes from 16 small, gauged catchments in the agricultural areas of south western Australia. It also describes methods for estimating flood runoff volumes from ungauged catchments. The independent variables found to be statistically significant in explaining the variability in flood runoff volumes from the gauged catchments were catchment area, mean annual rainfall and the percentage of the catchment that was cleared. No soil factor was found to be significant.

Groundwater Study Of The Woodanilling Townsite, Ben Whitfield

Resource management technical reports

A groundwater study was carried out in the townsite of Woodanilling, Western Australia. It aimed to accelerate the implementation of effective salinity management options. The study consisted of a drilling investigation, installation of a piezometer network, groundwater flow modelling and a flood risk analysis.

Groundwater Study Of The Koorda Townsite, Louise Hopgood

Resource management technical reports

A groundwater study was carried out in the townsite of Koorda. It aimed to accelerate the implementation of effective salinity risk management. The study consisted of a drilling investigation and expansion of a piezometer network, a pumping test, groundwater flow modelling and a flood risk analysis.

Discrete Maximum Principle For Nonsmooth Optimal Control Problems With Delays, Boris S. Mordukhovich, Ilya Shvartsman

Mathematics Research Reports

We consider optimal control problems for discrete-time systems with delays. The main goal is to derive necessary optimality conditions of the discrete maximum principle type in the case of nonsmooth minimizing functions. We obtain two independent forms of the discrete maximum principle with transversality conditions described in terms of subdifferentials and superdifferentials, respectively. The superdifferential form is new even for non-delayed systems and may be essentially stronger than a more conventional subdifferential form in some situations.

The Cataclysmic Variable Cw 1045+525: A Secondary-Dominated Dwarf Nova?, C. Tappert, J. R. Thorstensen, W. H. Fenton, N. Bennert, L. Schmidtobreick, A. Bianchini

Physics

We present spectroscopic and photometric observations of the cataclysmic variable CW 1045+525. Both the optical spectrum and the photometric lightcurve show a strong contribution of a K5V-M0V secondary. We derive an orbital period d by measuring the radial velocities of the absorption lines of the secondary. The period and spectral type of the secondary suggest a distance of 350-700 pc. There is evidence for additional sources of line- and continuum emission, but no direct evidence of an accretion disc. We discuss several scenarios for the nature of CW 1045+525 on the basis of our results, finding a dwarf nova classification …

Computer Sound Card Assisted Measurements Of The Acoustic Doppler Effect For Accelerated And Unaccelerated Sound Sources, Thomas J. Bensky, S. E. Frey

Physics

An approach to experimentally measuring the speed of a moving object by direct application of the Doppler effect for sound is discussed. The method presented here uses a Windows computer and sound card to record Doppler shifted sound from a moving source. This sound card approach allows for direct acquisition of Doppler shifted sound intensity as a function of time, affording much analytical and pedagogical freedom in undergraduate lab instruction. In addition, the acquisition of such data allows for the experimental study of not only constant velocity sound sources, but of accelerated sound sources as well.

Anatomy And Three-Dimensional Reconstructions Of The Brain Of A Bottlenose Dolphin (Tursiops Truncatus) From Magnetic Resonance Images, Lori Marino, Keith D. Sudheimer, Timothy L. Murphy, Kristina K. Davis, D. Ann Pabst, William A. Mclellan, James K. Rilling, John I. Johnson

Veterinary Science and Medicine Collection

Cetacean (dolphin, whale, and porpoise) brains are among the least studied mammalian brains because of the formidability of collecting and histologically preparing such relatively rare and large specimens. Magnetic resonance imaging offers a means of observing the internal structure of the brain when traditional histological procedures are not practical. Furthermore, internal structures can be analyzed in their precise anatomic positions, which is difficult to accomplish after the spatial distortions often accompanying histological processing. In this study, images of the brain of an adult bottlenose dolphin, Tursiops truncatus, were scanned in the coronal plane at 148 antero-posterior levels. From these scans …

Geosciences Newsletter - 2001, Department Of Geosciences

Geological and Environmental Sciences News

Vol.1, No. 26

• Faculty News
• Core Lab
• Groundwater Education of Michigan (GEM) Center
• Graduate Student News
• Alumni News
• Advisory Council News
• Donations

Atomic And Electronic Structure Of Co/Srtio3/Co Tunnel Junctions, Ivan I. Oleinik, Evgeny Y. Tsymbal, David G. Pettifor

Evgeny Tsymbal Publications

First-principles density-functional calculations of the atomic and electronic structure of Co/SrTiO₃ /Co (001) magnetic tunnel junctions (MTJ’s) are performed. Different interface terminations are considered and the most stable structure with the TiO₂ termination is identified based on energetics of adhesion. The calculated electronic structure of the TiO₂-terminated MTJ shows an exchange coupling between the interface Co and Ti atoms mediated by oxygen. This coupling induces a magnetic moment of 0.25 µ_B on the interface Ti atom, which is aligned antiparallel to the magnetic moment of the Co layer. We argue that this might cause an …

Bulletin No. 37: Living Resources And Habitats Of The Lower Connecticut River, Glenn D. Dreyer, Marcianna Caplis

Bulletins

No abstract provided.

Large Nondipole Effects In The Angular Distributions Of K-Shell Photoelectrons From Molecular Nitrogen, Oliver Hemmers, H. Wang, P. Focke, I. A. Sellin, Dennis W. Lindle, J. C. Arce, J. A. Sheehy, P. W. Langhoff

Environmental Studies Faculty Publications

Measurements of angular distributions of K-shell electrons photoejected from molecular nitrogen are reported which reveal large deviations at relatively low photon energies ( ħω≤500eV) from emission patterns anticipated from the dipole approximation to interactions between radiation and matter. A concomitant theoretical analysis incorporating the effects of electromagnetic retardation attributes the observed large nondipole behaviors in N₂ to bond-length-dependent terms in the E1⊗(E2,M1) photoelectron emission amplitudes which are indicative of a potentially universal nondipole behavior in molecular photoionization.

Inside Unlv, Diane Russell, Jennifer Vaughan, Richard Jensen, Mae Worthey-Flennoy

Inside UNLV

No abstract provided.

Deploying Integrated Web-Based Spatial Applications Within An Oracle Database Environment, James Carswell

Conference papers

In this paper, we describe the architectural and functional characteristics of e-Spatial™ technology, comprising an innovative software package that represents a timely alternative to traditional and complex proprietary GIS application packages. The two main components of the package, developed by e- Spatial Solutions, are the iSMART™ database development technology and the i-Spatial™ Information Server (iSIS), both implemented within an Oracle 9i Spatial database environment. This technology allows users to build and deploy spatially enabled or standard Internet applications without requiring any application-specific source code. It can be deployed on any Oracle supported hardware platform and on any device that supports …

Periodic Points Of The Family Of Tent Maps, Julio R. Hasfura-Buenaga, Phillip Lynch

Mathematics Faculty Research

No abstract provided.

Absorption Of Microwaves In La1Àxsrxmno3 Manganese Powders Over A Wide Bandwidth, G. Li, G. G. Hu, H. D. Zhou, Xiaojuan Fan, X. G. Li

Physics Faculty Research

We present the frequency dependence of microwave-absorbing properties of La_1-xSr_xMnO₃ (x=0.4, 0.5, 0.6, and 0.7) powders at room temperature. The absorbing properties change gradually with x in the frequency range of 8–12 GHz. The optimal absorption can be achieved for a x=0.4 sample and its microwave loss peak value is about 25 dB. Further experimental results show that the absorption can be attributed to magnetic and dielectric losses and the microwave loss peak corresponds to the maximum dielectric loss tangent tan δ_e near 10.5 GHz. Furthermore, the absorbing properties of the oxides mixed with …

Techniques For The Regeneration Of Wideband Speech From Narrowband Speech, Jason A. Fuemmeler, Russell C. Hardie, William R. Gardner

Electrical and Computer Engineering Faculty Publications

This paper addresses the problem of reconstructing wideband speech signals from observed narrowband speech signals. The goal of this work is to improve the perceived quality of speech signals which have been transmitted through narrowband channels or degraded during acquisition. We describe a system, based on linear predictive coding, for estimating wideband speech from narrowband. This system employs both previously identified and novel techniques. Experimental results are provided in order to illustrate the system’s ability to improve speech quality. Both objective and subjective criteria are used to evaluate the quality of the processed speech signals.

Ccd Photometry Of The Classic Second-Parameter Globular Clusters M3 And M13, Soo-Chang Rey, Suk-Jin Yoon, Young-Wook Lee, Brian Chaboyer, Ata Sarajedini

Dartmouth Scholarship

We present high-precision V, B-V color-magnitude diagrams (CMDs) for the classic second-parameter globular clusters M3 and M13 from wide-field, deep CCD photometry. The data for the two clusters were obtained during the same photometric nights with the same instrument, allowing us to determine accurate relative ages. Based on a differential comparison of the CMDs using the Δ(B-V) method, an age difference of 1.7 ± 0.7 Gyr is obtained between these two clusters. We compare this result with our updated horizontal-branch (HB) population models, which confirm that the observed age difference can produce the …

Mobile-Agent Versus Client/Server Performance: Scalability In An Information-Retrieval Task, Robert S. Gray, David Kotz, Ronald A. Peterson, Joyce Barton, Daria Chacon, Peter Gerken, Martin Hofmann, Jeffrey Bradshaw, Maggie Breedy, Renia Jeffers, Niranjan Suri

Dartmouth Scholarship

Building applications with mobile agents often reduces the bandwidth required for the application, and improves performance. The cost is increased server workload. There are, however, few studies of the scalability of mobile-agent systems. We present scalability experiments that compare four mobile-agent platforms with a traditional client/server approach. The four mobile-agent platforms have similar behavior, but their absolute performance varies with underlying implementation choices. Our experiments demonstrate the complex interaction between environmental, application, and system parameters.

Chromospherically Active Stars. Xx. The Giant Single-Lined Binary Hd 161570, Francis C. Fekel, Gregory W. Henry, Stephen M. Henry

Information Systems and Engineering Management Research Publications

Spectroscopy of HD 161570 shows it to be a single-lined spectroscopic binary with a period of 45.623 days and a nearly circular orbit. The primary star has spectral type G7 III, and the secondary is most likely a G or K dwarf. A high-resolution spectrum of the 3950 Å region confirms that the primary has Ca II H and K emission lines. The logarithm of the giant's lithium abundance is less than 0.9, indicating that it is not lithium-rich. From photometric observations covering six seasons, we detected periodic short-term light variability with an amplitude ranging from 0.02 to 0.04 mag. …

Fast Implementation Of Depth Contours Using Topological Sweep, Kim Miller, Suneeta Ramaswami, Peter Rousseeuw, Toni Sellarès, Diane Souvaine, Ileana Streinu, Anja Struyf

Computer Science: Faculty Publications

The concept of location depth was introduced in statistics as a way to extend the univariate notion of ranking to a bivariate configuration of data points. It has been used successfully for robust estimation, hypothesis testing, and graphical display. These reguire the computation of depth regions, which form a collection of nested polygons. The center of the deepest region is called the Tukey median. The only available implemented algorithms for the depth contours and the Tukey median are slow, which limits their usefulness. In this paper we describe an optimal algorithm which computes all depth contours in &Ogr;(n 2) time …

Volumes And Areas Of Early Weichselian Ice Dammed Lakes In Northern Russia, Martin Jakobsson, Jan Mangerud, Valery Astakov, John Inge Svendsen

Center for Coastal and Ocean Mapping

No abstract provided.

Harmonising Chart And Navigation-Related Information On Ecdis, Lee Alexander

Center for Coastal and Ocean Mapping

ECDIS is a real-time navigation system that integrates a variety of chart and navigation-related information. More than simply a replacement for a paper nautical chart, ECDIS is capable of continuously determining a vessel's position in relation to land, charted objects, aids-to-navigation, and unseen hazards. Increasingly, ECDIS is being used for both navigation and collision-avoidance tasks. There is growing concern about the display of ever-increasing amounts of both chart and navigation-related information. When it comes to using ECDIS, displaying more information is not necessarily better. Too much information (i.e., clutter) may only lead to confusion. In this regard, there is need …