Efficacy of selected pesticides against Tyrophagus putrescentiae (Schrank): influences of applied concentration, application substrate, and residual activity over time

2016 ◽  
Vol 90 (1) ◽  
pp. 379-387 ◽  
Author(s):  
Salehe Abbar ◽  
M. W. Schilling ◽  
R. Jeff Whitworth ◽  
Thomas W. Phillips
2019 ◽  
Vol 24 (6) ◽  
pp. 992-997 ◽  
Author(s):  
Hulya Dizlek ◽  
Mehmet Karagoz ◽  
Farid Faraji ◽  
Ibrahim Cakmak

This study was conducted to determine mite species in dried figs in Aydin, Turkey between August 2014 and November 2016. A total of 141 dried fig samples were taken from producers’ storage, commercial storages and fig processing factories in Buharkent, Germencik, Incirliova, Kocarli, Kosk, Kuyucak, Merkez, Nazilli, Sultanhisar and Yenipazar districts. In addition, 24 dried fig samples were kept in storage for 8 months and the changes in mite species composition and their densities in stored figs were determined. As a result, 8 mite species belonging to 3 orders and 5 families were identified from the dried figs. Acarus siro L., Carpoglyphus lactis (L.), Glycyphagus destructor (Schrank), G. domesticus (De Geer) and Tyrophagus putrescentiae (Schrank) as pest species, and Blattisocius tarsalis (Berlese), B. mali (Oudemans) and Cheyletus eruditus (Schrank) as predatory mite species were found. Out of 141 samples, 133 were infested with mites and the infestation ratio was 94.3%. Tyrophagus putrescentiae was the most common pest species with an infestation rate of 72.3%, followed by C. lactis with 34.8%, A. siro, G. destructor and G. domesticus with 0.7% contamination, respectively. Carpoglyphus lactis was found to have the highest density with 10,488 individuals/kg in contaminated fig samples. Blattisocius tarsalis was the most common predatory mite species with an infestation rate of 77.3%. Blattisocius mali and C. eruditus were found in 9.2% and 4.3% of dried figs, respectively. This study showed that the dried fig samples kept in storage were always vulnerable to contamination with mites. Mite species composition and their densities also fluctuated over time.


Author(s):  
Josué Herrera-Bojórquez ◽  
Emilio Trujillo-Peña ◽  
José Vadillo-Sánchez ◽  
Martin Riestra-Morales ◽  
Azael Che-Mendoza ◽  
...  

Abstract Fitting long-lasting insecticidal nets (LLIN) as screens on doors/windows has a significant impact on indoor-adult Aedes aegypti (L.), with entomological reductions measured in a previous study being significant for up to 2 yr post-installation, even in the presence of pyrethroid-resistant Aedes populations. To better understand the mode of LLIN protection, bioassays were performed to evaluate the effects of field deployment (0, 6, and 12 mo) and damage type (none, central, lateral, and multiple) on LLIN efficacy. Contact bioassays confirmed that LLIN residual activity (median knockdown time, in minutes, or MKDT) decreased significantly over time: 6.95 (95% confidence interval [CI]: 5.32–8.58) to 9.24 (95% CI: 8.69–9.79) MKDT at 0- and 12-mo age, respectively, using a pyrethroid-susceptible Aedes strain. Tunnel tests (exposing human forearm for 40 min as attractant) showed that deployment time affected negatively Aedes passage inhibition from 54.9% (95% CI: 43.5–66.2) at 0 mo to 35.7% (95% CI: 16.3–55.1) at 12 mo and blood-feeding inhibition from 65.2% (95% CI: 54.2–76.2) to 48.9% (95% CI: 26.4–71.3), respectively; both the passage/blood-feeding inhibition increased by a factor of 1.8–2.9 on LLINs with multiple and central damages compared with nets with lateral damage. Mosquito mortality was 74.6% (95% CI: 65.3–83.9) at 0 mo, 72.3% (95% CI: 64.1–80.5) at 6 mo, and 59% (95% CI: 46.7–71.3) at 12 mo. Despite the LLIN physical integrity could be compromised over time, we demonstrate that the remaining chemical effect after field conditions would still contribute to killing/repelling mosquitoes.


2008 ◽  
Vol 22 (3) ◽  
pp. 502-506 ◽  
Author(s):  
Diego J. Bentivegna ◽  
Reid J. Smeda

Cut-leaved teasel is an invasive weed along highway corridors and is classified noxious in four states, including Missouri. Few herbicides have been examined for cut-leaved teasel control. Herbicides were evaluated for efficacy on established plants and residual activity for suppressing seedling emergence. Various growth regulator herbicides, amino acid inhibitors, and paraquat were applied on established teasel at two locations in central Missouri in fall 2003 and spring 2004, and two additional locations in fall 2004 and spring 2005. At 2 wk after treatment (WAT), paraquat resulted in the highest injury of teasel (85%), but injury declined over time. At 4 WAT, teasel control was most consistent with dicamba + diflufenzopyr applied in spring, ranging from 75 to 94% control. At 8 wk, glyphosate, dicamba + diflufenzopyr, metsulfuron-methyl, imazapyr, and combinations of growth regulator herbicides with 2,4-D were most effective, with teasel control from 86 to 100%. Control with 2,4-D alone was inconsistent; sulfosulfuron, sulfometuron-methyl, and paraquat were ineffective. Residual herbicides did not reduce teasel seedling emergence the following year. A number of herbicides were effective in managing emerged plants but reinfestations of treated sites is likely, even with the residual herbicides used in this research.


2021 ◽  
Vol 51 ◽  
Author(s):  
Virgínia Damin ◽  
Bruno da Silva Carrijo ◽  
Nathalia Almeida Costa

ABSTRACT Soil attributes may affect the residual activity and impacts of herbicides on non-target organisms. This study aimed to evaluate the residual activity of the sulfentrazone herbicide and its impacts on microbiological parameters of Brazilian Savanna soils, as well as to identify soil attributes that can be used to predict the residual activity of the herbicide in these soils. The experimental design was completely randomized, in a 6 x 5 factorial scheme, with 4 replications, being 5 soil types (Rhodic Acrustox; Typic Quartzpsamment; Rhodic Haplustox; Typic Humaquepts; Fluventic Dystrustepts) and 6 periods (0, 15, 30, 45, 60 and 90 days after herbicide application - DAA). The residual activity of the sulfentrazone herbicide is dependent of the soil type, and the time that the herbicide can control at least 80 % of Urochloa decumbens plants ranges from 0 (Typic Humaquepts) to 38 days (Rhodic Haplustox). The bases saturation is the only soil attribute correlated with the herbicide efficacy over time, in the Brazilian Savanna soils, showing a moderate correlation up to 90 DAA. The pH, organic matter and clay content are not correlated with the herbicide efficacy over time in these soils. Sulfentrazone reduces the microorganisms activity from 45 to 90 DAA in all the studied soils. However, it does not affect the microbial biomass carbon.


2018 ◽  
Vol 41 ◽  
Author(s):  
David Hirshleifer ◽  
Siew Hong Teoh

AbstractEvolved dispositions influence, but do not determine, how people think about economic problems. The evolutionary cognitive approach offers important insights but underweights the social transmission of ideas as a level of explanation. The need for asocialexplanation for the evolution of economic attitudes is evidenced, for example, by immense variations in folk-economic beliefs over time and across individuals.


1988 ◽  
Vol 19 (3) ◽  
pp. 251-258 ◽  
Author(s):  
Virginia I. Wolfe ◽  
Suzanne D. Blocker ◽  
Norma J. Prater

Articulatory generalization of velar cognates /k/, /g/ in two phonologically disordered children was studied over time as a function of sequential word-morpheme position training. Although patterns of contextual acquisition differed, correct responses to the word-medial, inflected context (e.g., "picking," "hugging") occurred earlier and exceeded those to the word-medial, noninflected context (e.g., "bacon," "wagon"). This finding indicates that the common view of the word-medial position as a unitary concept is an oversimplification. Possible explanations for superior generalization to the word-medial, inflected position are discussed in terms of coarticulation, perceptual salience, and the representational integrity of the word.


2020 ◽  
Vol 29 (1S) ◽  
pp. 412-424
Author(s):  
Elissa L. Conlon ◽  
Emily J. Braun ◽  
Edna M. Babbitt ◽  
Leora R. Cherney

Purpose This study reports on the treatment fidelity procedures implemented during a 5-year randomized controlled trial comparing intensive and distributed comprehensive aphasia therapy. Specifically, the results of 1 treatment, verb network strengthening treatment (VNeST), are examined. Method Eight participants were recruited for each of 7 consecutive cohorts for a total of 56 participants. Participants completed 60 hr of aphasia therapy, including 15 hr of VNeST. Two experienced speech-language pathologists delivered the treatment. To promote treatment fidelity, the study team developed a detailed manual of procedures and fidelity checklists, completed role plays to standardize treatment administration, and video-recorded all treatment sessions for review. To assess protocol adherence during treatment delivery, trained research assistants not involved in the treatment reviewed video recordings of a subset of randomly selected VNeST treatment sessions and completed the fidelity checklists. This process was completed for 32 participants representing 2 early cohorts and 2 later cohorts, which allowed for measurement of protocol adherence over time. Percent accuracy of protocol adherence was calculated across clinicians, cohorts, and study condition (intensive vs. distributed therapy). Results The fidelity procedures were sufficient to promote and verify a high level of adherence to the treatment protocol across clinicians, cohorts, and study condition. Conclusion Treatment fidelity strategies and monitoring are feasible when incorporated into the study design. Treatment fidelity monitoring should be completed at regular intervals during the course of a study to ensure that high levels of protocol adherence are maintained over time and across conditions.


2008 ◽  
Vol 18 (2) ◽  
pp. 87-98 ◽  
Author(s):  
Vinciya Pandian ◽  
Thai Tran Nguyen ◽  
Marek Mirski ◽  
Nasir Islam Bhatti

Abstract The techniques of performing a tracheostomy has transformed over time. Percutaneous tracheostomy is gaining popularity over open tracheostomy given its advantages and as a result the number of bedside tracheostomies has increased necessitating the need for a Percutaneous Tracheostomy Program. The Percutaneous Tracheostomy Program at the Johns Hopkins Hospital is a comprehensive service that provides care to patients before, during, and after a tracheostomy with a multidisciplinary approach aimed at decreasing complications. Education is provided to patients, families, and health-care professionals who are involved in the management of a tracheostomy. Ongoing prospective data collection serves as a tool for Quality Assurance.


2008 ◽  
Vol 42 (7) ◽  
pp. 26-27
Author(s):  
MARY ELLEN SCHNEIDER

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