Rebecca L. Freeman

Telemedicine-based alcohol services for rural offenders.

Research has consistently shown that alcohol use is a problem in rural communities and access to substance abuse treatment, particularly evidence-based treatment is limited. Because telemedicine has been shown to be effective in delivering services, this article presents a novel and innovative way of using telemedicine technology in the form of videoconferencing to deliver an evidence-based alcohol intervention (motivational enhancement therapy) with at-risk alcohol users in real-world settings (rural probation and parole offices). This article focuses on: (a) creating a profile of an at-risk group of rural alcohol users; (b) describing the evidence-based intervention; and (c) describing the innovative telemedicine-based service delivery approach.

First Report of a Larval Shell Repair Scar on a Lingulate Brachiopod: Evidence of Durophagous Predation in the Cambrian Pelagic Realm?

Abstract A dorsal valve of an Upper Cambrian lingulate brachiopod exhibits a repair scar on the anterior lateral edge of its larval shell. This species is characterized by an abrupt change in ornamentation from larval to postlarval growth. Shell material secreted in the injured area after the damage occurred exhibits ornamentation that is characteristic of postlarval growth, although equivalent growth exhibits characteristics of the larval stage. A break in the edge of the shell is visible, and the growth lines of the larval and postlarval shell were distorted until the broken area was filled in. Damage to the surface of the shell is interpreted to have been caused by the same event. Modern lingulate brachiopod larvae are planktotrophic and are interpreted to have been so throughout their long geologic history. Therefore, an environmental cause of shell damage seems unlikely and the injuries are interpreted to have been caused by an unknown durophagous predator. This specimen offers evidence that lingulate brachiopod larvae were able to survive shell breakage and repair their shells.

GIANTS AMONG MICROMORPHS: WERE CINCINNATIAN (ORDOVICIAN, KATIAN) SMALL SHELLY PHOSPHATIC FAUNAS DWARFED?

Abstract Small fossils are preserved as phosphatic (carbonate fluorapatite) micro-steinkerns (~ 0.5 mm diameter) in Upper Ordovician beds of the Cincinnati area. Mollusks are common, along with bryozoan zooecia, echinoderm ossicles, and other taxa. Similar occurrences of Ordovician micromorphic mollusks have been interpreted as ecologically dwarfed and adapted to oxygen-starved conditions, an interpretation with implications for ocean anoxia. An alternative explanation for small phosphatic steinkerns is taphonomic. Stable carbonate fluorapatite selectively filled small voids, thus preserving small fossils, including larval/young mollusks. Reworking concentrated small phosphatic steinkerns from multiple generations while larger, unfilled calcareous shells were destroyed, resulting in small fossils progressively replacing larger fossils. With thin sections and insoluble residues, we document evidence that many of these steinkerns are incomplete (“teilsteinkerns”) recording small parts of larger, normal-sized animals, or juveniles, along with smaller species. This finding suggests that these fossil assemblages are taphonomically, not ecologically, size-limited. Based on the ecology of modern oxygen minimum zones in which shelled mollusks are rare, the presence of abundant shelled organisms actually argues against severe oxygen stress. Our results also imply that the process by which the “small shelly fossils” of the Cambrian were preserved continued into the Ordovician.

THE “CURSE OF RAFINESQUINA:” NEGATIVE TAPHONOMIC FEEDBACK EXERTED BY STROPHOMENID SHELLS ON STORM-BURIED LINGULIDS IN THE CINCINNATIAN SERIES (KATIAN, ORDOVICIAN) OF OHIO

ABSTRACT Thousands of lingulid brachiopods were found clustered beneath hundreds of individual valves of the strophomenid brachiopod Rafinesquina in the Upper Ordovician of Ohio. This association suggested a relationship between the two brachiopods, but the nature of this relationship was unclear. We utilized serial thin sectioning to examine these brachiopods and to determine the origin of the bed in which they were found. Sedimentary structures, mixed taphonomies, and stratigraphic and paleogeographic setting suggest that the lingulids occupied a hiatal concentration that had previously been reworked, but not significantly transported, by tropical storms. The final burial event was a storm that exhumed living lingulids along with disarticulated Rafinesquina shells from the same sediments. Neither living nor dead shells were transported, but were reworked locally, then reburied together. The lingulids then burrowed upward to escape, but most were trapped by the concave-downward Rafinesquina shells that had been redeposited above them. This finding offers the first documented example of negative ecosystem engineering and taphonomic feedback in the fossil record, as well as the oldest documented lingulid escape traces. It also suggests that taphonomic feedback can be subdivided into live-dead interactions that occur under normal background depositional conditions and those that occur during periodic short-lived sediment-reworking events, such as storms and tsunamis.

The proposed GSSP for the base of Cambrian Stage 10 at the First Appearance Datum of the conodont Eoconodontus notchpeakensis (Miller, 1969) in the House Range, Utah, USA

The Stage 10 Working Group of the International Subcommission on Cambrian Stratigraphy is tasked with recommending a stratotype section and horizon for the base of Stage 10, the uppermost stage of the Cambrian System. We identify three sections in the House Range in western Utah, USA, for consideration as locations for defining and characterizing the base of the proposed stage. We also propose a boundary horizon at the base of the Eoconodontus conodont Zone combined with a distinctive negative carbon-isotope excursion named the HEllnmaria–Red Tops Boundary (HERB) event. These and other biological and nonbiological tools can be used for correlating the proposed stage.

Linguliform brachiopods across a Cambrian–Ordovician (Furongian, Early Ordovician) biomere boundary: the Sunwaptan–Skullrockian North American Stage boundary in the Wilberns and Tanyard formations of central Texas

Abstract. The Cambrian-Ordovician Diversity Plateau, between the Cambrian Explosion and the Ordovician Radiation, is punctuated by a series of well-documented Laurentian trilobite extinction events. These events define the bounding surfaces of trilobite ‘biomeres’ that correspond to North American stages, including those of the Sunwaptan and Skullrockian. Trilobites show a consistent pattern of recovery across these boundaries, and commonly each extinction and replacement of taxa is interpreted as a single event as changing environmental conditions spurred shoreward migration of shelf or oceanic faunas that displaced established cratonic faunas. Linguliform brachiopods are also abundant in strata of this interval, and we investigate their stratigraphic distribution across the Sunwaptan-Skullrockian Stage boundary in Texas through high-resolution stratigraphic sampling of subtidal sediments. We document complete genus- and species-level turnover of the linguliform brachiopod fauna coincident with trilobite extinction events, suggesting that these brachiopods were affected by the same factors that affected trilobites. The Skullrockian replacement fauna was cosmopolitan, with ties to Gondwana and Kazakhstan and to the Laurentian shelf environment. The timing of appearances of taxa suggests that the faunal migration onto the Laurentian shelf came from elsewhere during a transgression. The disappearance of the Sunwaptan fauna and the arrival of the Skullrockian fauna are distinct events. We suggest that ‘biomere’ events may be complex, and the cause of the extinction is not necessarily the same event that facilitates the appearance of a replacement fauna. We describe one new species, Schizambon langei.