Artículos de conferencia

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Browsing Artículos de conferencia by Subject "02 Zero hunger"

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    AB1400-HPR Muscle quality index in obese subjects with hip osteoarthritis
    (2018) Jérez, D. A.; Machado, R.; Cerda Vega, Enrique
    Background: Obese older adults with hip osteoarthritis suffer a progressive loss of neuromuscular function affecting their activities of daily living. Objectives: The objective of this study is to determine the behaviour of the muscular quality index in obese subjects with osteoarthritis and to compare the manifestations of strength and anthropometric variables with control subjects. Methods: Thirty-two subjects (4 men and 28 women, 66.2±5.2 years of age, 159.2±7.5 cm, 71.5±11.7 kg) were evaluated. 14 subjects suffered osteoarthritis. Muscle circumference, limb length, body mass and sit and stand test were evaluated, in addition to the maximal voluntary isometric contraction in hip flexion and extension movements. Results: The osteoarthritis group presented obesity (p=0.037). The muscle quality index of the osteoarthritis group correlated with the weight (p=0.776**), with maximum peak strength in flexion (p=0.552*) and average maximal strength (p=0.574*). In the control group the muscle quality index correlated with: weight (p=0.689**), muscle circumference (p=0.571*), maximum peak strength in extension (p=0.534*), average peak strength in extension (p=0,523*), average maximal strength in extension (p=0.509*) and maximum impulse in extension (p=0.508*). Conclusions: The muscle quality index is a useful tool to measure muscle quality in the healthy population, but is not clear enough for obese subjects with osteoarthritis, so it is necessary to perform future studies to determine their behaviour.
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    Natural enemy communities of aphids in alfalfa fields assessed through video recordings of sentinel cards in scenarios of contrasting aphid abundance
    (2024) Grez, Audrey A.; Zaviezo, Tania; Molina, Gabriela
    The first step to better understand the relationship between natural enemy communities and pest control is to know which, when, and how frequently different natural enemies interact with their prey. In alfalfa fields of central Chile, aphids are the most common pests and are consumed by predators such as coccinellids, syrphids, and spiders. In this study, through video recording, we analyzed how natural enemy communities visiting aphid sentinel cards vary between scenarios of low and high abundance of aphids in alfalfa in spring. On 15 occasions, during the day, we monitored the natural enemies visiting cards with sentinel aphids (60 cards per field; total 900) located in fields with high (n = 6) and low (n = 9) aphid abundance. We also analyzed whether the abundance of coccinellid species visiting sentinel cards was related to their abundance in each field. In 750 h of video recording, we found 2749 natural enemies visiting the sentinel cards; 86.2% of them were coccinellids of five species. Total natural enemies and coccinellid visits were three times higher in low than in high aphid abundance scenarios. In contrast, the species richness and diversity of natural enemies and coccinellids visiting cards did not differ between aphid scenarios. The abundance of coccinellids in the field was positively associated with the abundance of coccinellids visiting cards, for the three most abundant species. Our study shows that video recording is useful for identifying changes in the communities of natural enemies of aphids in alfalfa, providing important new insights into trophic interactions in field situations.