35 research outputs found
A facial expression for anxiety.
Anxiety and fear are often confounded in discussions of human emotions. However, studies of rodent defensive reactions under naturalistic conditions suggest anxiety is functionally distinct from fear. Unambiguous threats, such as predators, elicit flight from rodents (if an escape-route is available), whereas ambiguous threats (e.g., the odor of a predator) elicit risk assessment behavior, which is associated with anxiety as it is preferentially modulated by anti-anxiety drugs. However, without human evidence, it would be premature to assume that rodent-based psychological models are valid for humans. We tested the human validity of the risk assessment explanation for anxiety by presenting 8 volunteers with emotive scenarios and asking them to pose facial expressions. Photographs and videos of these expressions were shown to 40 participants who matched them to the scenarios and labeled each expression. Scenarios describing ambiguous threats were preferentially matched to the facial expression posed in response to the same scenario type. This expression consisted of two plausible environmental-scanning behaviors (eye darts and head swivels) and was labeled as anxiety, not fear. The facial expression elicited by unambiguous threat scenarios was labeled as fear. The emotion labels generated were then presented to another 18 participants who matched them back to photographs of the facial expressions. This back-matching of labels to faces also linked anxiety to the environmental-scanning face rather than fear face. Results therefore suggest that anxiety produces a distinct facial expression and that it has adaptive value in situations that are ambiguously threatening, supporting a functional, risk-assessing explanation for human anxiet
Proceedings of the 23rd annual Central Plains irrigation conference
Presented at Proceedings of the 23rd annual Central Plains irrigation conference held in Burlington, Colorado on February 22-23, 2011
Proceedings of the 21st annual Central Plains irrigation conference, Colby Kansas, February 24-25, 2009
Presented at the 21st annual Central Plains irrigation conference on February 24-25, 2009 in Colby, Kansas
Reducing the cost of pumping irrigation water
Irrigation accounts for a large portion of the energy used in Nebraska agriculture. The cost to pump irrigation water depends on the type of energy used to power the pumping unit. This document describes a method to estimate the cost of pumping water and to compare the amount of energy used to that for a well maintained and designed pumping plant. The results can help determine the feasibility of repairing the pumping plant
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Handedness and behavioural inhibition system/behavioural activation system (BIS/BAS) scores: A replication and extension of Wright, Hardie, and Wilson (2009)
The Annett Hand Preference Questionnaire (AHPQ) as modified by Briggs and Nebes was administered along with Carver and White's behavioural inhibition system (BIS) and behavioural activation system (BAS) scale and a shortened form of the Big Five personality questionnaire to 92 university students. After eliminating the data from five respondents who reported having changed handedness and one outlier, there was a significant sex difference in mean BIS scores, with females (n = 43) scoring higher than males (n = 43). Replicating the results of Wright, Hardie and Wilson, non-right-handers (n = 36) had significantly higher mean BIS score than right-handers (n = 50). Controlling for sex of participant, neuroticism and BAS sub-scale scores in hierarchical regression analyses left this BIS effect substantially unaffected. There was no handedness or sex difference on any of the three BAS sub-scales. Further analyses revealed no association between strength, as distinct from direction, of handedness and BIS (or BAS) scores. The findings are discussed with reference to recent developments in reinforcement sensitivity theory on which BIS/BAS variables are based
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Fractionating negative and positive affectivity in handedness: Insights from the Reinforcement Sensitivity Theory of personality
The Annett Hand Preference Questionnaire (AHPQ), as modified by Briggs and Nebes [(1975). Patterns of hand preference in a student population. Cortex, 11(3), 230-238. doi: 10.1016/s0010-9452(75)80005-0 ], was administered to a sample of 177 participants alongside the Reinforcement Sensitivity Theory of Personality Questionnaire [RST-PQ; Corr, P. J., & Cooper, A. (2016). The Reinforcement Sensitivity Theory of Personality Questionnaire (RST-PQ): Development and validation. Psychological Assessment. doi: 10.1037/pas000 ], which measures two factors of defensive negative emotion, motivation and affectivity-the Behavioural Inhibition System (BIS) and the Fight-Flight-Freeze System (FFFS)-and one positive-approach dimension related to reward sensitivity, persistence and reactivity-the Behavioural Approach System. We sought to clarify the nature of negative, and positive, affectivity in relation to handedness. ANOVAs and multiple regression analyses converged on the following conclusions: left-handers were higher on the BIS, not the FFFS, than right-handers; in right-handers only, strength of hand preference was positively correlated with the FFFS, not the BIS. The original assessment method proposed by Annett was also used to assess handedness, but associations with RST-PQ factors were not found. These findings help us to clarify existing issues in the literature and raise new ones for future research
Secondary organic aerosol production from local emissions dominates the organic aerosol budget over Seoul, South Korea, during KORUS-AQ
Organic aerosol (OA) is an important fraction of submicron aerosols. However, it is challenging to predict and attribute the specific organic compounds and sources that lead to observed OA loadings, largely due to contributions from secondary production. This is especially true for megacities surrounded by numerous regional sources that create an OA background. Here, we utilize in situ gas and aerosol observations collected on board the NASA DC-8 during the NASA–NIER KORUS-AQ (Korea–United States Air Quality) campaign to investigate the sources and hydrocarbon precursors that led to the secondary OA (SOA) production observed over Seoul. First, we investigate the contribution of transported OA to total loadings observed over Seoul by using observations over the Yellow Sea coupled to FLEXPART Lagrangian simulations. During KORUS-AQ, the average OA loading advected into Seoul was ∼1–3 µg sm−3. Second, taking this background into account, the dilution-corrected SOA concentration observed over Seoul was ∼140 µgsm−3ppmv−1 at 0.5 equivalent photochemical days. This value is at the high end of what has been observed in other megacities around the world (20–70 µgsm−3ppmv−1 at 0.5 equivalent days). For the average OA concentration observed over Seoul (13 µg sm−3), it is clear that production of SOA from locally emitted precursors is the major source in the region. The importance of local SOA production was supported by the following observations. (1) FLEXPART source contribution calculations indicate any hydrocarbons with a lifetime of less than 1 day, which are shown to dominate the observed SOA production, mainly originate from South Korea. (2) SOA correlated strongly with other secondary photochemical species, including short-lived species (formaldehyde, peroxy acetyl nitrate, sum of acyl peroxy nitrates, dihydroxytoluene, and nitrate aerosol). (3) Results from an airborne oxidation flow reactor (OFR), flown for the first time, show a factor of 4.5 increase in potential SOA concentrations over Seoul versus over the Yellow Sea, a region where background air masses that are advected into Seoul can be measured. (4) Box model simulations reproduce SOA observed over Seoul within 11 % on average and suggest that short-lived hydrocarbons (i.e., xylenes, trimethylbenzenes, and semi-volatile and intermediate-volatility compounds) were the main SOA precursors over Seoul. Toluene alone contributes 9 % of the modeled SOA over Seoul. Finally, along with these results, we use the metric ΔOA/ΔCO2 to examine the amount of OA produced per fuel consumed in a megacity, which shows less variability across the world than ΔOA∕ΔCO
Secondary organic aerosol production from local emissions dominates the organic aerosol budget over Seoul, South Korea, during KORUS-AQ
Organic aerosol (OA) is an important fraction of submicron aerosols. However, it is challenging to predict and attribute the specific organic compounds and sources that lead to observed OA loadings, largely due to contributions from secondary production. This is especially true for megacities surrounded by numerous regional sources that create an OA background. Here, we utilize in situ gas and aerosol observations collected on board the NASA DC-8 during the NASA-NIER KORUS-AQ (Korea-United States Air Quality) campaign to investigate the sources and hydrocarbon precursors that led to the secondary OA (SOA) production observed over Seoul. First, we investigate the contribution of transported OA to total loadings observed over Seoul by using observations over the Yellow Sea coupled to FLEXPART Lagrangian simulations. During KORUS-AQ, the average OA loading advected into Seoul was similar to 1-3 mu g sm(-3). Second, taking this background into account, the dilution-corrected SOA concentration observed over Seoul was similar to 140 mu g sm(-3) ppmv 1 at 0.5 equivalent photochemical days. This value is at the high end of what has been observed in other megacities around the world (20-70 mu g sm(-3) ppmv(-1) at 0.5 equivalent days). For the average OA concentration observed over Seoul (13 mu g sm(-3)), it is clear that production of SOA from locally emitted precursors is the major source in the region. The importance of local SOA production was supported by the following observations. (1) FLEXPART source contribution calculations indicate any hydrocarbons with a lifetime of less than 1 day, which are shown to dominate the observed SOA production, mainly originate from South Korea. (2) SOA correlated strongly with other secondary photochemical species, including short-lived species (formaldehyde, peroxy acetyl nitrate, sum of acyl peroxy nitrates, dihydroxytoluene, and nitrate aerosol). (3) Results from an airborne oxidation flow reactor (OFR), flown for the first time, show a factor of 4.5 increase in potential SOA concentrations over Seoul versus over the Yellow Sea, a region where background air masses that are advected into Seoul can be measured. (4) Box model simulations reproduce SOA observed over Seoul within 11% on average and suggest that short-lived hydrocarbons (i.e., xylenes, trimethylbenzenes, and semi-volatile and intermediate-volatility compounds) were the main SOA precursors over Seoul. Toluene alone contributes 9% of the modeled SOA over Seoul. Finally, along with these results, we use the metric Delta OA/Delta CO2 to examine the amount of OA produced per fuel consumed in a megacity, which shows less variability across the world than Delta OA/Delta CO