Experimental and numerical investigation of methane ignition and flame propagation in cylindrical tubes ranging from 5 to 71 cm – Part I: Effects of scaling from laboratory to large-scale field studies

Abstract Preharvest aflatoxin contamination (PAC) of peanut occurs under prolonged periods of drought and heat stress. Evaluation of peanut germplasm may identify valuable sources of resistance to PAC, but will require a large scale screening system. The objective of this research was to develop a large-scale field system for screening peanut germplasm for resistance to PAC at Yuma, Arizona. Yuma is located in a desert and has great potential as a site for evaluating germplasm for resistance to PAC. Field studies were conducted in 1990 to determine if aflatoxin contamination would occur in drought stressed peanuts grown at Yuma. Aflatoxin levels up to 2,260 ppb were observed, however, 52% of the plots escaped contamination and the coefficient of variation (C.V.) were unacceptably large. During testing at Yuma in 1990 it was noted that drought stressed plants died quickly due to the rapid exhaustion of soil moisture. A subsurface irrigation system was installed in 1991 to alleviate this problem and allow for an extended period of drought stress in the pod zone. Results for 1991 showed a greatly increased mean aflatoxin contamination, a 50% reduction in the C.V., and a virtual elimination in the occurrence of escapes. A study was conducted in 1992 to compare plots with and without subsurface irrigation to determine if the differences observed between 1990 and 1991 were due to the use of subsurface irrigation. The use of subsurface irrigation in 1992 increased the mean contamination by over 100%, reduced the C.V. by over 50%, and reduced the percentage of escapes by over 90%.

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The influence of soil heterogeneity on exploratory tunnelling by the subterranean termite Coptotermes frenchi (Isoptera: Rhinotermitidae)

Bulletin of Entomological Research ◽

10.1079/ber2003254 ◽

2003 ◽

Vol 93 (5) ◽

pp. 413-423 ◽

Cited By ~ 25

Author(s):

T.A. Evans

Keyword(s):

Water Conservation ◽

Field Data ◽

Large Scale ◽

Laboratory Experiments ◽

Field Studies ◽

Soil Heterogeneity ◽

Large Field ◽

Small Scale ◽

Scale Field ◽

Large Scale Field

AbstractThe exploration of sand-filled arenas by workers of an entire colony of the Australian, subterranean foraging, tree-nesting termite, Coptotermes frenchi Hill was investigated under laboratory conditions. The first experiment tested whether termite exploration of sand was influenced by the presence of gaps or objects in the sand. Gaps and objects were chosen to represent soil heterogeneity in the urban environment: gaps to represent tunnels dug by other animals, perspex strips to represent cables and pipes, and wood strips to represent roots. Termites always chose to explore gaps thoroughly before they began tunnelling in the sand. Significantly more and longer tunnels were excavated from the end of gaps at the far end of the arenas, and relatively little tunnelling occurred around and along objects. Termite density was significantly greater around and along wood compared with perspex blocks. The second experiment tested whether termite exploratory tunnelling was influenced by soil moisture. The termites tunnelled slowly in dry sand, but after discovering a patch of wet sand, increased tunnelling five-fold until it was completely explored, after which activity declined. Energy and water conservation may be behind these patterns of exploratory tunnelling as well as those seen in large field studies, but caution is urged when interpreting small scale laboratory experiments to explain large scale field data.

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Full Disclosure: How Smartphones Enhance Consumer Self-Disclosure

Journal of Marketing ◽

10.1177/0022242920912732 ◽

2020 ◽

Vol 84 (3) ◽

pp. 28-45 ◽

Cited By ~ 7

Author(s):

Shiri Melumad ◽

Robert Meyer

Keyword(s):

Large Scale ◽

Personal Information ◽

Field Studies ◽

Self Disclosure ◽

Full Disclosure ◽

Wide Range ◽

Scale Field ◽

Large Scale Field ◽

Restaurant Reviews ◽

Survey Responses

Results from three large-scale field studies and two controlled experiments show that consumers tend to be more self-disclosing when generating content on their smartphone versus personal computer. This tendency is found in a wide range of domains including social media posts, online restaurant reviews, open-ended survey responses, and compliance with requests for personal information in web advertisements. The authors show that this increased willingness to self-disclose on one’s smartphone arises from the psychological effects of two distinguishing properties of the device: (1) feelings of comfort that many associate with their smartphone and (2) a tendency to narrowly focus attention on the disclosure task at hand due to the relative difficulty of generating content on the smaller device. The enhancing effect of smartphones on self-disclosure yields several important marketing implications, including the creation of content that is perceived as more persuasive by outside readers. The authors explore implications for how these findings can be strategically leveraged by managers, including how they may generalize to other emerging technologies.

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