Volume 5 Issue 2 September 2006

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https://doi.org/10.33697/ajur.2006.011

Editorial: Going from Good to Great

https://doi.org/10.33697/ajur.2006.012

Author(s):

C. C. Chancey

Affiliation:

American Journal of Undergraduate Research, University of Northern Iowa, Cedar Falls, Iowa 50614 USA


Reliability of Water Quality Test Strips for Field Measurement of Nutrients Essential for Developing Mosquito Larvae

https://doi.org/10.33697/ajur.2006.013

Authors and Affiliations:

Forest I. Isbell and David R. Mercer
Department of Biology, University of Northern Iowa, Cedar Falls, Iowa 50614-0421 USA
Mohammad Z. Iqbal
Department of Earth Science, University of Northern Iowa, Cedar Falls, Iowa 50614-0335 USA

ABSTRACT:

We tested the reliability of water quality test strips for field-analysis of nitrate and phosphate against laboratory-based standard methods for water samples drawn from a variety of natural and artificial sites used by mosquito larvae for development. Nitrate test strip measurements were compared with those from ion chromatographic analysis and an ion-selective electrode. Phosphate test strip measurements were compared to laboratory persulfate digestion followed by an ascorbic acid colorimetric assay. It was concluded that while the standard methods were the most reliable, nitrate-sensitive test strips were acceptable for measuring moderate nitrate concentrations, but phosphate-sensitive test strips were not reliable in measuring the forms of phosphorus available to mosquito larvae.


A Different Description of a Family of Middle-α Cantor Sets

https://doi.org/10.33697/ajur.2006.014

Author(s):

Mohsen Soltanifar

Affiliation:

Department Of Mathematics, Faculty of Science, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran, IRAN

ABSTRACT:

In this note we give an explicit description of a family of middle-α Cantor sets, with α = (q – 2)/q and q = 3, 4, 5…


Looking for the Elusive: Mining the VLA Archives for Radio Transients

https://doi.org/10.33697/ajur.2006.015

Author(s):

Destry R. Saul and Geoffrey C. Bower

Affiliation:

Astronomy Department and Radio Astronomy Laboratory, University of California – Berkeley, 601 Campbell Hall, Berkeley, California 94720 USA

ABSTRACT:

Detecting extragalactic radio transients will provide valuable information on several astronomical phenomena. Orphan gamma-ray burst afterglows (OGRBAs) and radio supernovae detection will be important for the theories of stellar collapse while the detection of tidal flares and variable active galactic nuclei (AGN) will provide details on massive black holes and galactic centers. In this paper we present the results of a survey we conducted using archived observations from the Very Large Array (VLA). We did not detect any transients in this set of data and from this we computed an upper limit on the rate of radio transients above 400 μJansky at 0.23 transients per square degree per year. This rules out one of several theories on the rates of OGRBAs.


The Structure of Digroups

https://doi.org/10.33697/ajur.2006.016

Authors and Affiliations:

Catherine Crompton
Department of Mathematics, Agnes Scott College, 141 E. College Avenue, Decatur, Georgia 30030 USA

Linda Scalici
Department of Mathematics, Bucknell University, Moore Avenue, Lewisburg, Pennsylvania 17837 USA

ABSTRACT:

A digroup is an algebra defined on a set having two associative binary operations, ⊢ and ⊣. Digroups play an important role in an open problem in the theory of Leibniz algebras. We present a brief overview of digroups and a set of more general axioms for a digroup than used previously. We then consider several properties of a digroup having distinct elements a and b such that a ⊢ b = b ⊢ a, but a ⊢ b ≠ a ⊣ b.