An Inquiry Into the Evolution and Sediments of Caves Along the Scioto River

Cave passages and the sediments contained in them often preserve large scale climate changes. The major rivers and tributaries in the Columbus area served as outlets for glacial melt waters. The down cutting of these rivers led to the formation of a phreatic to vadose transition in numerous local caves. There were two components to the research: Collection of sediment samples and searches of the surrounding area for clues to explain the caves’ evolution. Samples were collected in two major ways. The first, involved extracting surface sediment from caves with a rock hammer. The second employed a manual corer to extract deeper layers of sediment whenever possible. After collection, images of the samples were recorded to scale using a light station and camera. Many aspects of the caves were discovered, including that the parallel sets of caves on the banks were likely bisected by the river / stream. The sediment from the caves is a fine, clay-based mixture with some larger grains intermixed. Unfortunately, this composition is incompatible with the planned sieve analyses. Further research will explore the changes in spring locations along the Scioto River over time and analyze pollen and carbon data from new sediment samples.Shell Exploration and Production CompanyNo embarg

Rad51 Nucleoprotein Filament Disassembly Captured Using Fluorescent \u3cem\u3ePlasmodium falciparum\u3c/em\u3e SSB as a Reporter for Single-Stranded DNA

Single-stranded DNA binding (SSB) proteins coordinate DNA replication, repair, and recombination and are critical for maintaining genomic integrity. SSB binds to single-stranded DNA (ssDNA) rapidly and with very high affinity making it a useful molecular tool to detect free ssDNA in solution. We have labeled SSB from Plasmodium falciparum (Pf-SSB) with the MDCC (7-diethylamino-3-((((2-maleimidyl)ethyl)amino)-carbonyl)coumarin) fluorophore which yields a four-fold increase in fluorescence upon binding to ssDNA. Pf-SSBMDCC binding to DNA is unaffected by NaCl or Mg2+ concentration and does not display salt-dependent changes in DNA binding modes or cooperative binding on long DNA substrates. These features are unique to Pf-SSB, making it an ideal tool to probe the presence of free ssDNA in any biochemical reaction. Using this Pf-SSBMDCC probe as a sensor for free ssDNA, we have investigated the clearing of preformed yeast Rad51 nucleoprotein filaments by the Srs2 helicase during HR. Our studies provide a rate for the disassembly of the Rad51 filament by full length Srs2 on long ssDNA substrates. Mutations in the conserved 2B domain in the homologous bacterial UvrD, Rep and PcrA helicases show an enhancement of DNA unwinding activity, but similar mutations in Srs2 do not affect its DNA unwinding or Rad51 clearing properties. These studies showcase the utility of the Pf-SSB probe in mechanistic investigation of enzymes that function in DNA metabolism

Remote Storage: Leveraging Technology to Maximize Efficiency and Minimize Investments

Libraries are increasingly using, or at least considering, remote storage facilities for their little‐used materials in order to free up valuable on‐campus library space for other purposes. This paper details the experiences of one library, Northwestern University’s Pritzker Legal Research Center, in preparing for, then doing, this work. This type of work can be expensive in terms of staff time, particularly when staff is already being asked to do many additional things. Because extra staff could not be hired, Pritzker has experimented with alternative ways to get this work done, using relatively inexpensive and readily available technology, combined with the creativity of its staff, to accomplish this work with a minimum of time and other inputs while maintaining quality of work

Caries Presentation in Illict Drug Users and Excessive Soft Drink Consumers.

PosterAdvanced cervical caries in anterior teeth is common to two different patient behaviors. Rampant cervical caries (“meth mouth”) is a common presentation in drug users. Extensive consumption of soft drinks also presents a similar pattern of cervical caries. Two cases are presented and dental treatment considerations are discussed. Case One: excessive soft drink consumption. A young male presented to IUSD for evaluation and treatment of a painful #9. Clinical exam: #9 had extensive facial and cervical caries with a pulp exposure. Cervical caries on teeth #6, 7,8,10,11,12,13. Patient’s history revealed frequent daily consumption of multiple sweet soft drinks. #9 had become increasingly painful and that caused him to seek treatment. Pulpal and Percussion/Palpation testing and radiographic exam of #9 were conducted. Diagnosis: #9 Pulpal Necrosis with Symptomatic Apical Periodontitis. Treatment: Oral hygiene instruction to reduce the frequency of soft drink consumption. #9 was endodontically treated and restored. Caries in #6, 7,8,10,11,12,13 were treated and teeth restored. Case Two: cocaine abuse. A young female presented to IUSD for evaluation and treatment of a painful #9. Clinical exam: #9 had extensive cervical caries. Cervical caries on #7, 8, 9 and dental attrition. Patient reports having used cocaine for many years. Pulpal and Percussion/Palpation testing and radiographic exam of #9 were conducted. Diagnosis: #9 Pulpal Necrosis with Symptomatic Apical Periodontitis. Treatment considerations: Local anesthesia was achieved without the use of epinephrine due to possible occasional unreported use of cocaine. #9 was endodontically treated and restored. Patient did not return for continued treatment at IUSD. Conclusion: Cervical caries in anterior teeth associated with soft drinks demonstrate similar characteristics to those observed in patients with reported cocaine abuse. This should alert dental providers dentists to be aware of both illicit drug use and soft drink intake as part of the patient’s medical, dental, and social history information