Human Decomposition Ecology at the University of Tennessee Anthropology Research Facility

The University of Tennessee Anthropology Research Facility (ARF) is well known for its unique history as a site of human decomposition research in a natural environment. It has been integral to our understanding of the processes of human decomposition. Over the last 30 years 1,089 bodies have decomposed at this 1.28 acre facility, producing a density of 850 corpses per acre of land. This project evaluated the abiotic and biotic characteristics of the soil exposed to various levels of human decomposition in order to determine the effect on the physicochemical properties and the indigenous bacterial communities. Specifically, 75 soil samples were taken to determine abiotic properties. A biological matrix was generated for the 40 samples inside the facility based on sequencing of the 16S rDNA gene. The identified taxonomy was evaluated for differences among decomposition bins and taxa. Results of the abiotic soil properties demonstrated few differences among the predefined bins of decomposition density. Significant differences were observed between samples inside the facility to the negative control, and to those samples taken below actively decomposing corpses. When taken together, the abiotic data demonstrated a temporal shift away from control, with the greatest deviation at 18 to 24 months. After which time, the samples became more similar to control samples. Similarly, the biotic data remained concordant with the abiotic data, but demonstrated significant differences between the areas of high decomposition to those with no history of decomposition. The high decomposition bins were marked by high levels of chemoorganotrophic and sulfate-reducing bacteria, and a reduction in Acidobacteria, indicating a change in the community of underlying bacteria in response to carcass enrichment and ammonification of the soil. Thirty years of decomposition research at the ARF has forced a shift in the underlying bacterial community in response to the enrichment of the soil with increased nitrogen and carbon-containing compounds. The baseline data presented in this work provides a control dataset for further exploration regarding the biogeochemical relationships among microbial organisms, soil characteristics, and cadaver decomposition. Within this relationship exists the potential for developing new models relating to postmortem interval estimation and clandestine grave location

Quantitative study of the phytoplankton of Lake Michigan at Evanston, Illinois

At this point, December 1939, two years of collecting have been completed and an attempt has been made to summarize and compare the data for that period

Viola adunca var. bellidifolia (Greene) Harrington

https://thekeep.eiu.edu/herbarium_specimens_byname/20176/thumbnail.jp

Viola adunca var. bellidifolia (Greene) Harrington

https://thekeep.eiu.edu/herbarium_specimens_byname/20176/thumbnail.jp

ESL learners' perceptions of American dialects

This study was conducted to determine how ESL (English as a Second Language) learners' perception of American dialects differs from the perception of native American English speakers. 39 ESL students and 18 native speakers listened to and rated eight different speakers, representing four different dialects (i.e. Standard American English, Southern American English, African American English and Latino English). These speakers were rated on status, solidarity and language proficiency-related characteristics. The ESL and native speaker groups ranked the dialect groups similarly on status-related features (i.e. successful, smart, confident). However, the test groups had markedly different rankings of the dialect groups for solidarity-related features (i.e. dependable, funny, friendly). The ESL and native speaker groups had similar rankings concerning the speakers' language proficiency (i.e. speaking English well). However, with the exception of the Standard dialect, the ESL group generally viewed each dialect's proficiency more positively than the native speaker group.Master of Art

Aflatoxin Production in Corn by Aspergillus flavus Relative to Inoculation, Planting Date, and Harvest Moisture in Louisiana (Research Report #102)

Contamination of food and feed grains by aflatoxins is a problem throughout the world. Corn produced in the southeastern United States has higher levels of aflatoxin than corn produced in the Corn Belt of the Midwest.https://digitalcommons.lsu.edu/agcenter_researchreports/1008/thumbnail.jp

Chemosensory properties of murine nasal and cutaneous trigeminal neurons identified by viral tracing

BACKGROUND: Somatosensation of the mammalian head is mainly mediated by the trigeminal nerve that provides innervation of diverse tissues like the face skin, the conjunctiva of the eyes, blood vessels and the mucouse membranes of the oral and nasal cavities. Trigeminal perception encompasses thermosensation, touch, and pain. Trigeminal chemosensation from the nasal epithelia mainly evokes stinging, burning, or pungent sensations. In vitro characterization of trigeminal primary sensory neurons derives largely from analysis of complete neuronal populations prepared from sensory ganglia. Thus, functional properties of primary trigeminal afferents depending on the area of innervation remain largely unclear. RESULTS: We established a PrV based tracing technique to identify nasal and cutaneous trigeminal neurons in vitro. This approach allowed analysis and comparison of identified primary afferents by means of electrophysiological and imaging measurement techniques. Neurons were challenged with several agonists that were reported to exhibit specificity for known receptors, including TRP channels and purinergic receptors. In addition, TTX sensitivity of sodium currents and IB4 binding was investigated. Compared with cutaneous neurons, a larger fraction of nasal trigeminal neurons showed sensitivity for menthol and capsaicin. These findings pointed to TRPM8 and TRPV1 receptor protein expression largely in nasal neurons whereas for cutaneous neurons these receptors are present only in a smaller fraction. The majority of nasal neurons lacked P2X(3 )receptor-mediated currents but showed P2X(2)-mediated responses when stimulated with ATP. Interestingly, cutaneous neurons revealed largely TTX resistant sodium currents. A significantly higher fraction of nasal and cutaneous afferents showed IB4 binding when compared to randomly chosen trigeminal neurons. CONCLUSION: In conclusion, the usability of PrV mediated tracing of primary afferents was demonstrated. Using this technique it could be shown that compared with neurons innervating the skin nasal trigeminal neurons reveal pronounced chemosensitivity for TRPM8 and TRPV1 channel agonists and only partially meet properties typical for nociceptors. In contrast to P2X(3 )receptors, TRPM8 and TRPV1 receptors seem to be of pronounced physiological relevance for intranasal trigeminal sensation

Electrophysiological characterization of activation state-dependent Cav2 channel antagonist TROX-1 in spinal nerve injured rats

AbstractPrialt, a synthetic version of Cav2.2 antagonist ω-conotoxin MVIIA derived from Conus magus, is the first clinically approved voltage-gated calcium channel blocker for refractory chronic pain. However, due to the narrow therapeutic window and considerable side effects associated with systemic dosing, Prialt is only administered intrathecally. N-triazole oxindole (TROX-1) is a novel use-dependent and activation state-selective small-molecule inhibitor of Cav2.1, 2.2 and 2.3 calcium channels designed to overcome the limitations of Prialt. We have examined the neurophysiological and behavioral effects of blocking calcium channels with TROX-1. In vitro, TROX-1, in contrast to state-independent antagonist Prialt, preferentially inhibits Cav2.2 currents in rat dorsal root ganglia (DRG) neurons under depolarized conditions. In vivo electrophysiology was performed to record from deep dorsal horn lamina V/VI wide dynamic range neurons in non-sentient spinal nerve-ligated (SNL) and sham-operated rats. In SNL rats, spinal neurons exhibited reduced responses to innocuous and noxious punctate mechanical stimulation of the receptive field following subcutaneous administration of TROX-1, an effect that was absent in sham-operated animals. No effect was observed on neuronal responses evoked by dynamic brushing, heat or cold stimulation in SNL or sham rats. The wind-up response of spinal neurons following repeated electrical stimulation of the receptive field was also unaffected. Spinally applied TROX-1 dose dependently inhibited mechanically evoked neuronal responses in SNL but not sham-operated rats, consistent with behavioral observations. This study confirms the pathological state-dependent actions of TROX-1 through a likely spinal mechanism and reveals a modality selective change in calcium channel function following nerve injury

Trunk muscle activation during movement with a new exercise device for lumbo‐pelvic reconditioning

Gravitational unloading leads to adaptations of the human body, including the spine and its adjacent structures, making it more vulnerable to injury and pain. The Functional Re‐adaptive Exercise Device (FRED) has been developed to activate the deep spinal muscles, lumbar multifidus (LM) and transversus abdominis (TrA), that provide inter‐segmental control and spinal protection. The FRED provides an unstable base of support and combines weight bearing in up‐right posture with side alternating, elliptical leg movements, without any resistance to movement. The present study investigated the activation of LM, TrA, obliquus externus (OE), obliquus internus (OI), abdominis, and erector spinae (ES) during FRED exercise using intramuscular fine‐wire and surface EMG. Nine healthy male volunteers (27 ± 5 years) have been recruited for the study. FRED exercise was compared with treadmill walking. It was confirmed that LM and TrA were continually active during FRED exercise. Compared with walking, FRED exercise resulted in similar mean activation of LM and TrA, less activation of OE, OI, ES, and greater variability of lumbo‐pelvic muscle activation patterns between individual FRED/gait cycles. These data suggest that FRED continuously engages LM and TrA, and therefore, has the potential as a stationary exercise device to train these muscles