216 research outputs found

    Long-Term Pyrene Exposure of Grass Shrimp, \u3ci\u3ePalaemonetes pugio\u3c/i\u3e, Affects Molting and Reproduction of Exposed Males and Offspring of Exposed Females

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    The objective of this study was to investigate the impact of long-term pyrene exposure on molting and reproduction in the model estuarine invertebrate, the grass shrimp (Palaemonetes pugio). Grass shrimp were exposed to measured concentrations of 5.1, 15.0, and 63.4 ppb (mu g/L) pyrene for 6 weeks, during which time we determined molting and survivorship. At the end of the exposure, we immediately sacrificed some of the shrimp for biomarker (CYP1A and vitellin) analyses. The remaining shrimp were used to analyze fecundity and embryo survivorship during an additional 6 weeks after termination of pyrene exposure. Male shrimp at the highest pyrene dose (63 ppb) experienced a significant delay in molting and in time until reproduction, and showed elevated ethoxycoumarin o-deethylase (ECOD) activity immediately after the 6-week exposure period. In contrast, 63 ppb pyrene did not affect these parameters in female shrimp. Females produced the same number of eggs per body weight, with high egg viability (98-100%) at all exposure levels, but with decreased survival for the offspring of the 63-ppb pyrene-exposed females. In addition, vitellin levels were elevated only in females at 63 ppb pyrene after the 6-week exposure. We hypothesize that the elevated vitellin binds pyrene and keeps it biologically unavailable to adult females, resulting in maternal transfer of pyrene to the embryos. This would account for the lack of effect of pyrene exposure on ECOD activity, molting, and reproduction in the adult females, and for reduced survival of their offspring

    Later achievement of infant motor milestones is related to lower levels of physical activity during childhood::the GECKO Drenthe cohort

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    BACKGROUND: The aim of this study is to investigate whether age of infant motor milestone achievement is related to levels of physical activity (PA), weight status and blood pressure at age 4-7 years of age. METHODS: In the Dutch GECKO (Groningen Expert Center of Kids with Obesity) Drenthe cohort, the age of achieving the motor milestone 'walking without support' was reported by parents. Weight status and blood pressure were assessed by trained health nurses and PA was measured using the Actigraph GT3X between age 4 and 7 years. RESULTS: Adjusted for children's age, sex and the mother's education level, infants who achieved walking without support at a later age, spent more time in sedentary behaviour during childhood and less time in moderate-to-vigorous PA. Later motor milestones achievement was not related to higher BMI Z-score, waist circumference Z-score, diastolic or systolic blood pressure. CONCLUSION: The results of this study indicate that a later age of achieving motor milestone within the normal range have a weak relation to lower PA levels at later age. It is not likely that this will have consequences for weight status or blood pressure at 4-7 years of age

    Algebraic lattice constellations: bounds on performance

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    In this work, we give a bound on performance of any full-diversity lattice constellation constructed from algebraic number fields. We show that most of the already available constructions are almost optimal in the sense that any further improvement of the minimum product distance would lead to a negligible coding gain. Furthermore, we discuss constructions, minimum product distance, and bounds for full-diversity complex rotated Z[i]/sup n/-lattices for any dimension n, which avoid the need of component interleaving

    Infant Motor Milestones and Childhood Overweight::trends over Two Decades in A Large Twin Cohort

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    BACKGROUND: Poor motor skill competence may influence energy balance with childhood overweight as a result. Our aim was to investigate whether the age of motor milestone achievement has changed over the past decades and whether this change may contribute to the increasing trend observed in childhood overweight. METHODS: Motor skill competence was assessed in children from the Young Netherlands Twin Register born between 1987 and 2007. Follow-up ranged from 4 up to 10 years. Weight and height were assessed at birth, 6 months, 14 months, and 2, 4, 7, and 10 years. RESULTS: Babies born in later cohorts achieved their motor milestones 'crawling', 'standing', and 'walking unassisted' later compared to babies born in earlier cohorts (N = 18,514, p < 0.001). The prevalence of overweight at age 10 was higher in later cohorts (p = 0.033). The increase in overweight at age 10 was not explained by achieving motor milestones at a later age and this persisted after adjusting for gestational age, sex, and socioeconomic status. CONCLUSION: Comparing children born in 1987 to those born in 2007, we conclude that children nowadays achieve their motor milestones at a later age. This does not however, explain the increasing trend in childhood overweight

    The role of fitness in the association between fatness and cardiometabolic risk from childhood to adolescence

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    Background Fatness and fitness both influence cardiometabolic risk. Objective The purpose of this study was to investigate whether childhood fatness and increasing fatness from childhood to adolescence are associated with cardiometabolic risk during adolescence and how fitness affects this association. Subjects and methods Of 565 adolescents (283 boys and 282 girls) from the TRacking Adolescents Individual Life Survey (TRAILS) data on anthropometric parameters (age 11 and 16), metabolic parameters, and fitness (age 16) were available. Body mass index and skinfolds were used as measures for fatness. Increasing fatness was calculated by subtracting Z-scores for fatness at age 11 from Z-score fatness at age 16. Cardiometabolic risk was calculated as the average of the standardized means of mean arterial pressure, fasting serum triglycerides, high-density lipoprotein-cholesterol, glucose, and waist circumference. Insulin resistance was calculated by homeostasis model assessment-insulin resistance (HOMA-IR). Fitness was estimated as maximal oxygen consumption (VO2max) during a shuttle run test. Results Boys showed a higher clustered cardiometabolic risk when compared to girls (p < 0.01). Childhood fatness (age 11) and increasing fatness were independently associated with cardiometabolic risk during adolescence. In boys, high fitness was related to a reduced effect of increasing fatness on clustered cardiometabolic risk. Childhood fatness, increasing fatness, and fitness were independently associated with HOMA-IR. Moreover, in boys this association was dependent of fatness. Conclusions Childhood fatness and increasing fatness are associated with increased cardiometabolic risk and HOMA-IR during adolescence, but a good fitness attenuates this association especially in fat boys

    What Does Belonging Mean? A framing and network approach to tackle loneliness among students

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    Are you working in an educational context or are you interested in the wellbeing of students? Then this workshop is interesting for you! At the faculty of Industrial Design Engineering, Delft University of Technology, we set up The Belonging Project. This is a research project that seeks to understand and learn how we can design for belongingness and human connectedness. According to the Cambridge dictionary, when you belong, you are in the right place or you feel happy or comfortable in a situation1. Every person has this intrinsic need to belong and form relationships, and therefore, your sense of belonging impacts your overall wellbeing. In our project, we are particularly interested in young people – children, teenagers, students – as human connection and well-being are also intrinsically connected to learning and thereby have a great impact on their chance to flourish in life. What we currently notice in our society, is that interventions mostly focus on how to make miserable people less miserable. Within our project, we are interested in what happens if we flip this focus on curing to prevention, and ask ourselves ‘how can we make young people flourish’? However, this is also what makes ‘promoting belonging’ a systemic challenge: as belonging and relatedness concern to almost every aspect of our life, there is no obvious stakeholder or organisation that can be held responsible for promoting it. This made us curious: can we, as design researchers, create a shift in social innovation towards prevention and reinforce the wellbeing of young people? Can we foster the development of a so-called designing network, consisting of (public) organisations that create interventions by using the ‘fertile ground’ that derives from our design research? Are our developed design practices useful for these organisations in addressing such an open, complex, dynamic and networked problem

    Changes in empowerment and anxiety of patients and parents during genetic counselling for epilepsy

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    Genetic testing and counselling are increasingly important in epilepsy care, aiming at finding a diagnosis, understanding aetiology and improving treatment and outcome. The psychological impact of genetic counselling from patients' or parents & rsquo; perspectives is, however, unknown. We studied the counseleereported outcome of genetic counselling before and after genetic testing for epilepsy by evaluating empowerment - a key outcome goal of counselling reflecting cognitive, decisional and behavioural control, emotional regulation and hope - and anxiety. We asked patients or their parents (for those (c) 2021 The Author(s). Published by Elsevier Ltd on behalf of European Paediatric Neurology Society. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

    Impact of the carbon flux regulator protein pirC on ethanol production in engineered cyanobacteria

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    Future sustainable energy production can be achieved using mass cultures of photoautotrophic microorganisms such as cyanobacteria, which are engineered to synthesize valuable products directly from CO2 and sunlight. For example, strains of the model organism Synechocystis sp. PCC 6803 have been generated to produce ethanol. Here, we performed a study to prove the hypothesis that carbon flux in the direction of pyruvate is one bottleneck to achieve high ethanol titers in cyanobacteria. Ethanol-producing strains of the cyanobacterium Synechocystis sp. PCC 6803 were generated that bear mutation in the gene pirC aiming to increase carbon flux towards pyruvate. The strains were cultivated at different nitrogen or carbon conditions and the ethanol production was analysed. Generally, a clear correlation between growth rate and ethanol production was found. The mutation of pirC, however, had only a positive impact on ethanol titers under nitrogen depletion. The increase in ethanol was accompanied by elevated pyruvate and lowered glycogen levels indicating that the absence of pirC indeed increased carbon partitioning towards lower glycolysis. Metabolome analysis revealed that this change in carbon flow had also a marked impact on the overall primary metabolism in Synechocystis sp. PCC 6803. Deletion of pirC improved ethanol production under specific conditions supporting the notion that a better understanding of regulatory mechanisms involved in cyanobacterial carbon partitioning is needed to engineer more productive cyanobacterial strains
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