38 research outputs found

    Coccinelídeos associados ao olival português e sua importância na protecção contra a cochonilha-negra, Saissetia oleae (Olivier)

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    Os coccinelídeos são um dos grupos de insectos predadores mais importantes nos ecossistemas agrícolas e, no olival são dos principais inimigos da cochonilha-negra, Saissetia oleae. Neste trabalho indicam-se as espécies de coccinelídeos identificadas em olivais localizados nas principais regiões olivícolas portuguesas (Alto Alentejo. Trás-os-Montes e Beira interior Norte) e analisa-se o papel das espécies consideradas de maior importância na limitação natural da cochonilha-negra. Os dados apresentados obtiveram-se em 1999 e 2000 e entre 2002 e 2004. por amostragem, através da técnica das pancadas, realizada semanal ou quinzenalmente. As populações de cochonilha-negra amostraram-se quinzenalmente, em 2002 e 2003, através da observação de cinco amostras de 160 folhas provenientes de dez árvores, em dois olivais de Trás-os-Montes. A importância dos coccinelídeos como potenciais predadores de cochonilha-negra foi avaliada quer através do estabelecimento de correlações entre a abundância de coccinelídeos e a abundância dos diferentes estados de desenvolvimento da praga, quer através da detecção de vestígios de cochonilha-negra no intestino dos coccinelídeos por métodos serológicos (ELISA-indirecto). No total, identificaram-se 28 espécies de coccínelídeos, das quais Chilocorus bipuswlatus, Scymnus (Pullus) med1terraneus. Scymnus (Pullus) subvillosus, Scymnus (Scymnus) interruptus e Rhyzobius chrysomeloides foram as espécies mais representativas no total dos olivais estudados. Relativamente à predação de cochontlha-negra, o segundo estado ninfal foi o que apresentou maior número de correlações estatisticamente significativas com quatro das cinco espécies de coccinelídeos estudadas, sendo potencialmente o estado de desenvolvimento mais predado. Por outro lado, os resultados obtidos através dos testes ELISA permitiram indicar oito espécies de coccínelídeos (C. bipustulotus, E. quodrípustulotus. S. med/Lerroneus, N. bístgnotus, s. subvíllosus, S. opetzi, S. interruptus e R. chrysomeloides) como potenciais predadores de cochonilha-negra. Os resultados obtidos apontam para o grande interesse destes insectos na limitação natural da cochonilha-negra no olival

    Effects of shoulder compensatory strength training program in rotator cuff strength of young swimmers.

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    INTRODUCTION The purpose of this study was to evaluate de effects of 16 week compensatory strength training program in shoulder strength and respective conventional ratios (concentric ER/IR). METHODS A total of 40 national level male swimmers were assessed and randomly divided in two groups – experimental group (N=20)-(age:14.65±0.67 years old, height:173.48±6.87 cm, body mass:63.15±5.68 kg) and control group (N=20)-(age:14.60±0.60 years old, height: 170.79±6.48 cm, body mass:61.73±4.68 kg). Experimental subjects participated in a 16 week shoulder strength program with Thera-Band® elastic bands (3 times a week). The peak-torque of shoulder internal (IR) and external rotators (ER) was measured in both groups at baseline and after 16 weeks. Concentric action at 60º/s (3 rep) and 180º/s (20 rep) were measured, in a seated position, with the shoulder at 90º of abduction and the elbow flexed to 90º, using an isokinetic dynamometer (Biodex System 3 – Biodex Corp., Shirley, USA). Anova with repeated measures was used to determine significant main effects in shoulder rotators strength and unilateral ER/IR ratios. The level of significance was set at 0.05. RESULTS Significant differences were found in all variables that measure the ER shoulder strength at 60º/s in dominant(DT) (P=0.031) and non-dominant(NDT) shoulder (P=0.001). Meanwhile concentric action at 180º/s, only showed significant differences on DT shoulder (P=0.032). In respect of ER/IR ratio, a compensatory strength training programme induces significant differences in both shoulders at 60º/s (DT: P=0.001; NDT: P=0.001). At 180º/s we just found significant effects on the DT ER/IR ratio (P=0.002). DISCUSSION The results of this study support earlier research [1] that showed that the unilateral shoulder strength ratios increases substantially after a period of a strength training program. Since the ratios describe the quality of muscular balance/imbalance [1], we can conclude that a 16 week compensatory shoulder strength training program using Thera-Band® elastic bands, reduces muscular imbalances in rotator cuff of competitive young swimmers. These results highlight the useful of this kind of compensatory program to prevent shoulder injuries

    Can Physical Activity Make Up for the Self-Care Disability Effects of Too Much Sitting? A Moderation Analysis in Octogenarians Residing in Living Care Facilities

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    Background: and Purpose: Physical activity can delay the progression of self-care disability in older adults residing in living care facilities. Nonetheless, older adults residing in living care facilities spend most of their time sedentary and do not meet the physical activity recommendation, which may result in increasing self-care disability in this population group. In this study, we aimed to determine whether the association between sedentary time and self-care disability was moderated by moderate-to-vigorous physical activity (MVPA) in older adults residing in living care facilities. Methods: Sedentary time and MVPA were both measured with accelerometers. Self-care disability was assessed with the Barthel Index. A multivariate regression model was used to ascertain the effects of the interaction between sedentary time and MVPA on the self-care disability of participants. The Johnson-Neyman technique was then used to estimate the exact MVPA threshold at which the effect of sedentary time on self-care disability became nonsignificant. Results: We found a significant effect of sedentary time on self-care disability (standardized β = −1.66; 95% CI −1.77 to −1.54, P = .013). Results indicated that MVPA moderates the relationship between self-care disability status and sedentary time (standardized β = 1.14; 95% CI 1.13 to 1.14, P = .032). The Johnson-Neyman technique determined that 51 min/day of MVPA would offset the negative effects of sedentary time on self-care disability. Conclusions: Our results suggest physical therapists should focus on reducing sedentary time alongside physical activity to prevent the progression to dependency in octogenarians residing in living care facilities

    Rotator cuff isokinetic strength of young group aged swimmers in a competitive training program

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    Introduction: In any given sports activity, muscular or movement instability is pointed out as having a high influence for the maintenance of correct joint functionality. In swimming, due to the repetitive use of shoulder muscles, there is a higher tendency to promote injuries at the shoulder joint, especially when instability between the internal (IR) and external (ER) shoulder rotators is present. The aims of this study were to evaluate the rotator cuff isokinetic strength in order to determine any possible muscular over compensation or imbalance, and to assess differences between the dominant and non-dominant side, of young group aged swimmers. Methods: Forty young aged swimmers in a competitive training program were evaluated, and divided in two groups. Only subjects without any previous history of strength training were included. Group 1 (n=19), age 15 to 16 (years); height [mean (SD)] 168.6 (6.5) (centimeters); weight 59.6 (6.0) (kilograms), training/week 113.7 (12.6) (minutes); experience 5.3 (1.6) (years) and Group 2 (n=21); age 13 to 14; height 160.5 (12.2); weight 50.4 (10.8); training/week 88.6 (17.7); experience 4.1 (2.2) (years). The maximal unilateral isokinetic strength was measured (Biodex System 3) on the shoulder IR and ER during concentric action at 60°/second, bilaterally. Data was examined by the application of appropriate statistical tests for the analysis of variance. Results: Statistical differences were found on peak torque (Nm) at the agonist/antagonist ratio measured unilaterally [Group 1: right shoulder 35.8 (7.9) (IR) and 25.8 (4.7) (ER) (p=0.001) and left shoulder 32.7 (6.7) (IR) and 23.9 (5.1) (ER) (p=0.001) / Group 2: right shoulder 23.4 (6.5) (IR) and 19.0 (5.4) (ER) (p=0.048) and left shoulder 22.4 (5.4) (IR) and 16.8 (6.1) (ER) (p=0.027)]. However, no statistical differences were found between the maximal rotation strength measured bilaterally [Group 1: ER (p=0.280) and IR (p=0.246) / Group 2: ER (p=0.186) and IR (p=0.522)]. Conclusion: Young swimmers involved in a competitive training program can suffer from unilateral over compensation at shoulder IR or ER. This compensation seems to increase with the number of training years. To enable a higher stability between the internal and external shoulder rotators it is recommended that shoulder muscle strengthening should be considered in young aged swimmers training programs

    Abdominal obesity in adolescents: Development of age-specific waist circumference cut-offs linked to adult IDF criteria

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    We provide age- and sex-specific cut-off points that can be used to identify abdominal obesity in adolescents. The present findings provide a tool that can be used in the clinical setting for the early detection and prevention of adult obesity. Population-specific cutoffs may be required for pediatric ages to diagnose children at risk. 1 | INTRODUCTION The prevalence of pediatric overweight and obesity has increased substantially over the past decades in both developed and developing countries (Ng et al., 2014; de Onis, Blosser, & Borghi, 2010). The risk of overweight and obese youth becoming overweight adults is at least twice as high as their regular-weight peers (Singh, Mulder, Twisk, Van Mechelen, & Chinapaw, 2008). Body mass index (BMI) is a widely recognized surrogate of obesit

    Fitness efficacy of vibratory exercise compared to walking in postmenopausal women

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    In this study, we compared the efficacy of 8 months of low-frequency vibration and a walk-based program in health-related fitness. Twenty-seven postmenopausal women were randomly assigned into two groups: whole-body vibration (WBV) group (n = 18) performed three times/week a static exercise on a vibration platform (6 sets of 1-min with 1 min of rest, with a 12.6 Hz of frequency and an amplitude of 3 mm); walk-based program (WP) group (n = 18) performed three times/week a 60-min of walk activity at 70-75% of maximal heart rate. A health-related battery of tests was applied. Maximal unilateral concentric and eccentric isokinetic torque of the knee extensors was recorded by an isokinetic dynamometer. Physical fitness was measured using the following tests: vertical jump test, chair rise test and maximal walking speed test over 4 m. Maximal unilateral isokinetic strength was measured in the knee extensors in concentric actions at 60 and 300 degrees /s, and eccentric action at 60 degrees /s. After 8 months, the WP improved the time spent to walk 4 m (20%) and to perform the chair rise test (12%) compared to the WBV group (P = 0.006, 0.002, respectively). In contrast, the comparison of the changes in vertical jump showed the higher effectiveness of the vibratory exercise in 7% (P = 0.025). None of exercise programs showed change on isokinetic measurements. These results indicate that both programs differed in the main achievements and could be complementary to prevent lower limbs muscle strength decrease as we age [ISRCTN76235671]

    Low-frequency vibratory exercise reduces the risk of bone fracture more than walking: a randomized controlled trial

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    BACKGROUND: Whole-body vibration (WBV) is a new type of exercise that has been increasingly tested for the ability to prevent bone fractures and osteoporosis in frail people. There are two currently marketed vibrating plates: a) the whole plate oscillates up and down; b) reciprocating vertical displacements on the left and right side of a fulcrum, increasing the lateral accelerations. A few studies have shown recently the effectiveness of the up-and-down plate for increasing Bone Mineral Density (BMD) and balance; but the effectiveness of the reciprocating plate technique remains mainly unknown. The aim was to compare the effects of WBV using a reciprocating platform at frequencies lower than 20 Hz and a walking-based exercise programme on BMD and balance in post-menopausal women. METHODS: Twenty-eight physically untrained post-menopausal women were assigned at random to a WBV group or a Walking group. Both experimental programmes consisted of 3 sessions per week for 8 months. Each vibratory session included 6 bouts of 1 min (12.6 Hz in frequency and 3 cm in amplitude with 60° of knee flexion) with 1 min rest between bouts. Each walking session was 55 minutes of walking and 5 minutes of stretching. Hip and lumbar BMD (g·cm(-2)) were measured using dual-energy X-ray absorptiometry and balance was assessed by the blind flamingo test. ANOVA for repeated measurements was adjusted by baseline data, weight and age. RESULTS: After 8 months, BMD at the femoral neck in the WBV group was increased by 4.3% (P = 0.011) compared to the Walking group. In contrast, the BMD at the lumbar spine was unaltered in both groups. Balance was improved in the WBV group (29%) but not in the Walking group. CONCLUSION: The 8-month course of vibratory exercise using a reciprocating plate is feasible and is more effective than walking to improve two major determinants of bone fractures: hip BMD and balance

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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