A Taxonomic Study of Variation in Leptochloa Fascicularis (LAM.) Gray in the Central Great Plains

The morphology of Leptochloa fascicularis (Lam.) Gray (Poaceae) was studied in 25 locations in eastern and central Nebraska to determine if this grass was separable into two distinct taxa as suggested in several recent sources. Field collections were supplemented with herbarium specimens from other parts of the Central Great Plains. Glume and lemma lengths, the characters used in published keys, provided no separations useful in dividing the material into two species or varieties. However, individual local populations exhibited significant differences from each other in these characters. Such local differences appear to be reasonable given the high degree of inbreeding that appears to be prevalent at most locations

A taxonomic study of variation in Leptochloa fascicularis in the central Great Plains.

Morphology of Leptochloa fascicularls (Lam.) Gray (Poaceae) was studied in 25 locations in eastern and central Nebraska to determine if this grass was separable into two distinct taxa as suggested in several recent sources. Field collections were supplemented with herbarium samples from the University of Kansas. Glume and lemma lengths, the characters used in published keys, provided no separations useful in dividing the material into two species or varieties. However, individual local populations exhibited significant differences from each other in these characters. Such local differences appear to be reasonable given the high degree of inbreeding that is to be expected with cleistogamous reproduction such as that predominating at most of the more xeric field locations. Chasmogamy was confined to moist habitats

How distant? An experimental analysis of students’ COVID-19 exposure and physical distancing in university buildings

University buildings are significant closed built environments for COVID-19 spreading. As universities prepare to re-start in-class activities, students' adherence to physical distancing requirements is a priority topic. While physical distancing in classrooms can be easily managed, the movement of students inside common spaces can pose higher risks due to individuals' proximity. This paper provides an experimental analysis of unidirectional student flow inside a case-study university building, by investigating students' movements and grouping behaviour according to physical distancing requirements. Results show general adherence with the minimum required physical distancing guidance, but some spaces, such as corridors, pose higher exposure than doorways. Their width, in combination with group behaviour, affects the students' capacity to keep the recommended distance. Furthermore, students report higher perceived vulnerability while moving along corridors. Evidence-based results can support decision-makers in understanding individuals' exposure in universities and researchers in developing behavioural models in preparation of future outbreaks and pandemics.Comment: 22 pages, 5 figures, 1 table. Currently submitted to "International Journal of Disaster Risk Reduction

How distant? An experimental analysis of students’ COVID-19 exposure and physical distancing in university buildings

Closed university buildings proved to be one of the main hot spots for virus transmission during pandemics. As shown during the COVID-19 pandemic, physical distancing is one of the most effective measures to limit such transmission. As universities prepare to manage in-class activities, students’ adherence to physical distancing requirements is a priority topic. Unfortunately, while physical distancing in classrooms can be easily managed, the movement of students inside common spaces can pose high risk of close proximity. This paper provides an experimental analysis of unidirectional student movement inside a case-study university building to investigate how physical distancing requirements impact student movement and grouping behaviour. Results show general adherence with the minimum required physical distancing guidance, but spaces such as corridors pose higher risk of exposure than doorways. Doorway width, in combination with group behaviour, affect the students' capacity to keep the recommended physical distance. Furthermore, questionnaire results show that students report higher perceived vulnerability while moving along corridors. Evidence-based results can support decision-makers in understanding individuals’ exposure to COVID-19 in universities and researchers in developing behavioural models in preparation of future outbreaks and pandemics

Lessons learned from a Tiger Worm Toilet implementation project in Sierra Leone

This paper discusses the implementation of Tiger Worm Toilets (TWTs) as a sustainable alternative to pit latrines in areas with challenging environmental conditions. The study was carried out in Koinadugu, Sierra Leone, where TWTs were installed in 200 households, providing safe sanitation for approximately 1,200 individuals within a 17-month period. The study reveals that TWTs offer several benefits over traditional pit latrines, including higher cost efficiency. Despite some setbacks, TWTs have been well-received by the local communities, resulting in a significant reduction in open defaecation in areas where latrines are not viable. The study presents areas of further research and concludes with recommendations for future TWT designs based on the lessons learned