752 research outputs found

    Backyard Bug Collecting Results in 6 New State Records for Arkansas, U.S.A.

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    The aquatic Hemiptera of Arkansas are fairly well documented (see Chordas et al. 2005), but the terrestrial bugs are less well known. Recent projects and publications have begun to address this deficiency. Including the 6 reported herein, there have been 64 Hemiptera species newly recorded for Arkansas between 2005 and 2009 (Chordas et al. 2005, Chordas and Kovarik 2008a, Chordas and Kovarik 2008b). The second author is an invertebrate enthusiast who maintains a large personal collection. The content of this collection is primarily an accumulation of invertebrates captured on or around his property in Clarksville (Johnson County) Arkansas (Figure 1). Identification of the Hemiptera from this “backyard bug collection” revealed 6 species (in 4 Hemiptera families) that are new state records for Arkansas. These 6 include: 2 Coreidae (Leaf-footed bugs), Acanthocephala declivis (Say, 1832) and Piezogaster calcarator (Fabricius, 1803); 1 Largidae (Largid bugs), Largus succinctus (Linnaeus, 1763); 2 Lygaeidae (Seed bugs), Lygaeus kalmii angustomarginatus Parshley, 1919 and Neacoryphus bicrucis (Say, 1825) and 1 Reduviidae (Assassin bugs), Sirthenea stria carinata (Fabricius, 1798). Of note, our record of L. succinctus is the first Arkansas record for this hemipteran family

    Frequency dependency of temporal contrast adaptation in normal subjects

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    AbstractThe aim of this study was to determine the influence of temporal frequency of temporal contrast adaptation on contrast sensitivity in healthy subjects. Temporal contrast sensitivities (TCS) were measured monocularly in seven healthy subjects with a modified ERG full-field bowl stimulator at eight different test temporal frequencies (9, 15, 20, 25, 31, 37, 44, 51Hz) using a two-alternative-forced-choice strategy. Before each presentation of the test stimulus, a 100% contrast adapting flicker stimulus was presented (frequencies: 9, 15, 20, 25, 31, 37, 44, 51, 100Hz). At each adapting frequency, a complete set of TCSs was measured. All temporal contrast sensitivities decreased with increasing temporal frequencies. Adaptation led to a general temporal contrast sensitivity decrease. Largest adaptation effects were seen at an adaptation frequency of 25Hz. Reduction of contrast sensitivity was significantly larger at 25Hz adaptation than at 9Hz adaptation (t-test of paired samples, Bonferroni corrected). The results of this study showed a general TCS decrease with the largest effect at an adaptation frequency of 25Hz. This finding indicates that the contrast adaptation probably occurred in the magnocellular-pathway. In future clinical studies adaptation effects could be investigated in patients with reduced temporal contrast sensitivity

    Context matters! The relationship between mother-reported family nutrition climate, general parenting, food parenting practices and children’s BMI

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    Background: Efforts to explain children’s nutrition behavior or weight often involve investigating the parent-child relationship, typically studying the associations between food parenting practices (FPPs) and child outcomes. However, these behaviors are embedded in a broader system: general parenting (GP, the general emotional climate at home), and the family health climate (an aspect of the broader family system in the context of health). In the current study, we combined the parent-child measures of parenting (FPPs and GP) and the nutritional dimension of the family health climate (family nutrition climate, FNC) to get a broader view of how these concepts are interrelated. The current study had two aims: predicting FPPs using GP and FNC as predictor variables, and investigating the relationship between FPPs and children’s weight in different groups of parents, based on low and high GP and FNC scores. Methods: We collected cross-sectional data via an online survey panel. Mothers of 267 children aged 5–12 years filled out a questionnaire assessing demographics (e.g., children’s weight and height), GP, FPPs, and FNC. Bivariate correlation coefficients were calculated between all constructs. Structural equation modeling was performed to test the hypothesized relationships between GP, FNC and FPPs. Hereafter, different groups of parents were identified, using median split, based on a low or high score on GP or a low or high score on FNC. Bivariate correlation coefficients were calculated between FPPs and children’s BMI z-score for these different groups. Results: GP and FNC were consistently positively correlated (all r’s ≄.177), and both concepts were positively associated with healthy FPPs (all r’s ≄.214). In families with a positive context (i.e. scoring high on GP and on FNC), healthy FPPs were associated with lower BMI z-scores of the children (r -.229). This association was not found for children with a more negative family context. Conclusions: FNC and GP are valuable additional concepts to investigate relationships between FPPs and child outcomes. We recommend that more studies, next to investigating the parent-child system, include a measure of the broader family system, in order to get a broader view of the mechanisms explaining child health behaviors and weight status

    Continuity theorems for the M/M/1/nM/M/1/n queueing system

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    In this paper continuity theorems are established for the number of losses during a busy period of the M/M/1/nM/M/1/n queue. We consider an M/GI/1/nM/GI/1/n queueing system where the service time probability distribution, slightly different in a certain sense from the exponential distribution, is approximated by that exponential distribution. Continuity theorems are obtained in the form of one or two-sided stochastic inequalities. The paper shows how the bounds of these inequalities are changed if further assumptions, associated with specific properties of the service time distribution (precisely described in the paper), are made. Specifically, some parametric families of service time distributions are discussed, and the paper establishes uniform estimates (given for all possible values of the parameter) and local estimates (where the parameter is fixed and takes only the given value). The analysis of the paper is based on the level crossing approach and some characterization properties of the exponential distribution.Comment: Final revision; will be published as i

    Aerobic and strength exercises for youngsters aged 12 to 15: what do parents think?

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    BACKGROUND: Although strength exercises evidently have both physiological and psychological health benefits across all ages, they are erroneously considered to adversely affect health status in youngsters. The aim of this study was to examine parental attitudes towards their child's physical activity in general, as well as aerobic and strength exercises in particular. METHODS: In total, 314 parents from an online panel representative of the Dutch population completed an online survey about their own physical activity and that of their child (12-15 years old). The study also explored reasons for non-participation, and attitudes about the parents' own and their child's physical activity level. RESULTS: Parents consistently reported a positive attitude towards aerobic exercises, but a less positive attitude regarding strength exercises. Parents were more likely to indicate that their child was not allowed to participate in strength exercises (29.6 %) than aerobic exercises (4.0 %). They thought that strength exercises could interfere with optimal physical development. CONCLUSIONS: This study consistently shows that parents have a positive attitude towards aerobic exercises, but a less positive attitude regarding strength exercises. We suggest testing interventions to increase parental understanding of the advantages of and possibilities for (e.g., facilities) strength training on their child's health

    Effects of an intervention aimed at reducing the intake of sugar-sweetened beverages in primary school children: A controlled trial

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    Abstract Background Since sugar-sweetened beverages (SSB) may contribute to the development of overweight in children, effective interventions to reduce their consumption are needed. Here we evaluated the effect of a combined school- and community-based intervention aimed at reducing children’s SSB consumption by promoting the intake of water. Favourable intervention effects on children’s SSB consumption were hypothesized. Methods In 2011-2012, a controlled trial was conducted among four primary schools, comprising 1288 children aged 6-12 years who lived in multi-ethnic, socially deprived neighbourhoods in Rotterdam, the Netherlands. Intervention schools adopted the ‘water campaign’, an intervention developed using social marketing. Control schools continued with their regular health promotion programme. Primary outcome was children’s SSB consumption, measured using parent and child questionnaires and through observations at school, both at baseline and after one year of intervention. Results Significant positive intervention effects were found for average SSB consumption (B -0.19 litres, 95% CI -0.28;-0.10; parent report), average SSB servings (B -0.54 servings, 95% CI -0.82;-0.26; parent report) and bringing SSB to school (OR 0.51, 95% CI 0.36;0.72; observation report). Conclusions This study supports the effectiveness of the water campaign intervention in reducing children’s SSB consumption. Further studies are needed to replicate our findings. Trial registration Current Controlled Trials: NTR3400 webcit
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