BACKGROUND: Electric adjustable height desks (EAHD) have been promoted as an opportunity for desk based workers to stand at work but there is limited evidence that they have an effect on light physical activity. OBJECTIVE: The main objective was to determine if there would be a change in light physical activity with the introduction of EAHD. The secondary objective was to assess if there was an associated change in leisure time activity. METHODS: Activity levels were measured by step counts, self-reported activity levels and pre-and post-trial recall levels. Statistical analysis of the data was performed with the software R. Generalised linear models were fitted to the data. A Poisson regression was used for count data. Statistical hypotheses were deemed significant if their p values were less than 0.05. RESULTS: There was a significant (p < 0.001) effect on step counts associated with allocation of EAHD and a significant (p < 0.001) increase in self-reported activity for the Intervention (EAHD) group. Having an EAHD was associated with increased activity during leisure (p = 0.039). CONCLUSIONS: Activity levels, especially light physical activity, were significantly increased with the allocation of an electric adjustable height desk. This pilot study showed that the environmental change of introduction of electric adjustable height desks into an office workplace can increase physical activity and reduce sitting durations. There is limited evidence that the increase in work activity has a positive impact on leisure time activity.
The hematophagous bug Triatoma rubida is a species of kissing bug that has been marked as a potential vector for the transmission of Chagas disease in the Southern United States and Northern Mexico. However, information on the distribution of T. rubida in these areas is limited. Vector monitoring is crucial to assess disease risk, so effective trapping systems are required. Kissing bugs utilize extrinsic cues to guide host-seeking, aggregation, and dispersal behaviors. These cues have been recognized as high-value targets for exploitation by trapping systems. A modern video-tracking system was used with a four-port olfactometer system to quantitatively assess the behavioral response of T. rubida to cues of known significance. Also, response of T. rubida adults to seven wavelengths of light-emitting diodes (LED) in paired-choice pitfall was evaluated. Behavioral data gathered from these experiments indicate that T. rubida nymphs orient preferentially to airstreams at either 1600 or 3200 ppm carbon dioxide and prefer relative humidity levels of about 30%, while adults are most attracted to 470 nm light. These data may serve to help design an effective trapping system for T. rubida monitoring. Investigations described here also demonstrate the experimental power of combining an olfactometer with a video-tracking system for studying insect behavior.
This chapter provides information on the various cotton growing states of the USA and Mexico and the major cotton pests, diseases and weeds in these states and their management strategies.
Cotton bollworm, Helicoverpa zea (Boddie), development under environmental stress was evaluated in laboratory and field trials in southern New Mexico. Constant exposure to 35°C and 17% relative humidity in the laboratory resulted in only 4% egg hatch. Stressed by high temperature, 35°C, or low relative humidity, 17%, alone, hatch rates were comparable to eggs held at 26°C and 50% relative humidity. Larvae maintained at 35°C and 17% relative humidity had only 9% survival. Cumulative mortality under these most stressful conditions was 99.64% from egg to pupation. Larvae exposed to only one stress (35°C or 17% relative humidity) had similar survival to pupation, 29 to 32%, less than half the 67% survival at 26°C and 50% RH. Field trials tested the effects of row orientation and row spacing on H. zea hatching rates. Hatch rates in row orientation trials ranged from 37 to 79%, with only one significant difference in east‐west vs. north‐south oriented rows in two years. Row spacing had no impact on H. zea egg hatch. Hatch rates ranged from 43 to 71% with no significant difference among row spacings 17, 34, 68, and 96 cm. Bollworm is very susceptible to environmental stress. However, bollworm develops in the plant canopy where it is generally not significantly impacted by differences in row orientation or row spacing.
Bt cotton is used to control pink bollworm, Pectinophora gossypiella (Saunders), in much of the southwestern U.S. Where growers choose non-Bt varieties, early fruiting (squaring) Bt cotton might be used as a trap crop for pink bollworm control. Field tests were conducted in 1997 and 1998 to determine if early planting, varietal selection, and very low planting rates could increase early squaring. Cotton planted 4 April produced 6 mm squares approximately 11 days earlier than cotton planted 7 May. Low plant populations (4.3, 2.5 plants/m) did not result in more early squares, compared to recommended populations with 7.5 plants/m. Very dense populations with 18.4 vs. 9.4 plants/m produced more early squares/m despite fewer squares/plant. However, yield was reduced with planting rates above 7.5 plants/m. Some varieties produced more early-season squares than others, but differences were not always consistent. Paymaster 1215 produced significantly more early squares compared to two other short-season varieties (Deltapine 20B and Deltapine 50B) and the standard Acala 1517-95 in 1997, but not more than Acala 1517-95 in 1998. A mid-season variety (Paymaster 1560) produced the highest number of early squares in a comparison of ten Bt varieties in 1998. A non-Bt very short-season variety, Xpress, produced the earliest squares in 1997, more than 11 days earlier than Paymaster 1215 (a short-season variety), indicating that earlier squaring varieties of Bt cotton could be developed. These results indicate that early planting will provide the earliest squares but that variety and planting rate should be considered in developing a trap crop for pink bollworm control. Planting rate should be at least 7.5 plants/m but if yield is not a consideration could be as high as 18 plants/m.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.