Browsing by Author "Smith, Ryan C."
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- Alcohol Intoxication Checklist: A Naturalistic ApproachWotring, Brian; Antin, Jonathan F.; Smith, Ryan C. (National Surface Transportation Safety Center for Excellence, 2021-07-16)This effort sought to determine the prevalence of particular visual and behavioral indicators for alcohol intoxication using data collected in the Strategic Highway Research Program 2 Naturalistic Driving Study (SHRP 2 NDS). A list of visual and behavioral cues was identified from previous research and served as the basis for identification. The prevalence of several of these cues reached statistical significance between judged states of intoxication. Some cues include, but are not limited to, lids-heavy, dozing, exhilarated, distracted, talkative, inability to sit upright, yawning, and leaning against window. While the study was able to determine the prevalence of the markers, several limitations temper interpretation. First, a large proportion of trips evaluated occurred between midnight and 4:00 a.m., when drivers are likely to be drowsy and exhibit many of the same visual and behavioral indicators also expected to be present in intoxicated individuals. Thus, impacts of drowsiness may be confounded with those of intoxication. In addition, the same visual cues were used both to determine the degree of intoxication as well as the behaviors most associated thereto, thus resulting in a logical conundrum. The results of this research should be viewed as exploratory work that can aid in the generation of hypotheses for future work.
- The new Internal Transcribed Spacer 2 diagnostic tool clarifies the taxonomic position and geographic distribution of the North American malaria vector Anopheles punctipennisHodge, James M.; Yurchenko, Andrey A.; Karagodin, Dmitriy A.; Masri, Reem A.; Smith, Ryan C.; Gordeev, Mikhail I.; Sharakhova, Maria V. (2021-03-10)Background The malaria mosquito Anopheles punctipennis, a widely distributed species in North America, is capable of transmitting human malaria and is actively involved in the transmission of the ungulate malaria parasite Plasmodium odocoilei. However, molecular diagnostic tools based on Internal Transcribed Spacer 2 (ITS2) of ribosomal DNA are lacking for this species. Anopheles punctipennis is a former member of the Anopheles maculipennis complex but its systematic position remains unclear. Methods In this study, ITS2 sequences were obtained from 276 An. punctipennis specimens collected in the eastern and midwestern United States and a simple and robust Restriction Fragment Length Polymorphism approach for species identification was developed. The maximum-likelihood phylogenetic tree was constructed based on ITS2 sequences available through this study and from GenBank for 20 species of Anopheles. Results The analysis demonstrated a consistent ITS2 sequence length and showed no indications of intragenomic variation among the samples based on ITS2, suggesting that An. punctipennis represents a single species in the studied geographic locations. In this study, An. punctipennis was found in urban, rural, and forest settings, suggesting its potential broad role in pathogen transmission. Phylogeny based on ITS2 sequence comparison demonstrated the close relationship of this species with other members of the Maculipennis group. Conclusions This study developed molecular tools based on ITS2 sequences for the malaria vector An. punctipennis and clarified the phylogenetic position of the species within the Maculipennis group.