611 research outputs found

    Cognitive science and the cultural challenge

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111778/1/soca12120.pd

    My Heart Made Me Do It: Childrenā€™s Essentialist Beliefs About Heart Transplants

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    Psychological essentialism is a folk theory characterized by the belief that a causal internal essence or force gives rise to the common outward behaviors or attributes of a categoryā€™s members. In two studies, we investigated whether 4Ć¢ to 7Ć¢ yearĆ¢ old children evidenced essentialist reasoning about heart transplants by asking them to predict whether trading hearts with an individual would cause them to take on the donorā€™s attributes. Control conditions asked children to consider the effects of trading money with an individual. Results indicated that children reasoned according to essentialism, predicting more transfer of attributes in the transplant condition versus the nonĆ¢ bodily money control. Children also endorsed essentialist transfer of attributes even when they did not believe that a transplant would change the recipientā€™s category membership (e.g., endorsing the idea that a recipient of a pigā€™s heart would act pigĆ¢ like, but denying that the recipient would become a pig). This finding runs counter to predictions from a strong interpretation of the Ć¢ minimalistĆ¢ position, an alternative to essentialism.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138236/1/cogs12431_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138236/2/cogs12431.pd

    Effects of Hypoxia on Consumption, Growth, and RNA:DNA Ratios of Young Yellow Perch

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    As in various freshwater and coastal marine ecosystems worldwide, seasonal bottom water hypoxia is a recurring phenomenon in Lake Erieā€™s central basin. While bottom hypoxia can strongly affect sessile benthic animals, its effects on mobile organisms such as fish are less understood. We evaluated the potential for bottom hypoxia to affect the growth rates of yellow perch Perca flavescens, a species of ecological and economic importance in the lake. To this end, we (1) conducted laboratory experiments to quantify the effects of reduced dissolved oxygen on consumption, somatic growth, and RNAĀ :Ā DNA ratios (an index of shortā€term growth) of young yellow perch and (2) explored the effects of bottom hypoxia on young yellow perch growth in Lake Erieā€™s central basin by collecting individuals in hypoxicand normoxic regions of the lake and quantifying their RNAĀ :Ā DNA ratios. Yellow perch consumption and growth in our experiments declined under hypoxic conditions (ā‰¤2 mg O2/L). While yellow perch RNAĀ :Ā DNA ratios responded strongly to experimental temperature, nucleic acid ratios were not significantly affected by dissolved oxygen or feeding ration. We did, however, observe a positive correlation between yellow perch growth and RNAĀ :Ā DNA ratios at low temperatures (11Ā°C). The nucleic acid ratios of yellow perch collected in Lake Erie varied spatiotemporally, but their patterns were not consistent with hypoxia. In short, while yellow perch consumption and growth rates respond directly and negatively to low oxygen conditions, these responses are not necessarily reflected in RNAĀ :Ā DNA ratios. Moreover, in central Lake Erie, where yellow perch can behaviorally avoid hypoxic areas, the RNAĀ :Ā DNA ratios of yellow perch do not respond strongly to bottom hypoxia. Thus, this study suggests that there is no strong negative effect of bottom hypoxia on the growth of young yellow perch in Lake Erie.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141858/1/tafs1574.pd

    The association between benign prostatic hyperplasia and chronic kidney disease in community-dwelling men

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    The association between benign prostatic hyperplasia and chronic kidney disease in community-dwelling men.BackgroundBenign prostatic hyperplasia (BPH) and chronic kidney disease are important public health problems in older men. Previous referral-based studies disagree on whether BPH is associated with chronic kidney disease. The objective of this study was to determine the community-based association between clinical measures of BPH and chronic kidney disease.MethodsA community-based sample of 2115 white men (ages 40ā€“79 years) was randomly selected from the Olmsted County, Minnesota population (55% participation rate) in 1990. A random subsample (N = 476) had a detailed clinical evaluation. This evaluation included a questionnaire with similar queries to the International Prostate Symptom Score (IPSS), peak urinary flow rates (uroflowmeter), postvoid residual urine volume (ultrasound), prostate volume (ultrasound), serum prostate specific antigen (PSA), and serum creatinine.ResultsAfter adjustment for age, hypertension, diabetes, leukocyte esterase positive (possible urinary tract infection), and smoking, chronic kidney disease [serum creatinine ā‰„133 Ī¼mol/L (1.5 mg/dL)] was associated with diminished peak urinary flow rate (<15 mL/sec) by an odds ratio (OR) = 2.96 (95% CI 1.30ā€“7.01), moderate-severe lower urinary tract symptoms (IPSS >7) by an OR = 2.91 (95% CI 1.32ā€“6.62), and chronic urinary retention (postvoid residual >100 mL) by an OR = 2.28 (95% CI 0.66ā€“6.68). There was no association with a prostate volume >30 mL by an OR = 0.56 (95% CI 0.22ā€“1.37) or PSA >1.4 ng/mL by an OR = 1.17 (95% CI 0.47ā€“2.81).ConclusionThere was a cross-sectional association between signs and symptoms of bladder outlet obstruction and chronic kidney disease in community-dwelling men. Prostatic enlargement was not associated with chronic kidney disease

    Indirect consequences of hypolimnetic hypoxia on zooplankton growth in a large eutrophic lake

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    Diel vertical migration (DVM) of some zooplankters in eutrophic lakes is often compressed during peak hypoxia. To better understand the indirect consequences of seasonal hypolimnetic hypoxia, we integrated laboratory-based experimental and field-based observational approaches to quantify how compressed DVM can affect growth of a cladoceran, Daphnia mendotae, in central Lake Erie, North America. To evaluate hypoxia tolerance of D. mendotae, we conducted a survivorship experiment with varying dissolved oxygen concentrations, which demonstrated high sensitivity of D. mendotae to hypoxia (ā‰¤2 mg O2 lāˆ’1), supporting the field observations of their behavioral avoidance of the hypoxic hypolimnion. To investigate the effect of temporary changes in habitat conditions associated with the compressed DVM, we quantified the growth of D. mendotae, using a 3 (food quantity) Ɨ 2 (temperature) factorial design laboratory experiment. Neither food quantity nor temperature affected short-term growth in body length of D. mendotae. However, D. mendotae RNA content (an index of short-term condition) decreased under starvation, indicating an immediate response of short-term feeding on condition. We further evaluated the effect of hypoxia-induced upward shifts in vertical distribution by quantifying the RNA content of D. mendotae from central Lake Erie before and during peak hypoxia. Despite high temperature and food quantity in the upper water column, RNA content in field-collected D. mendotae remained low during peak hypoxia. Furthermore, D. mendotae collected during peak hypoxia consisted of only small-bodied

    The UK Soft Drinks Industry Levy and childhood hospital admissions for asthma in England

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    Sugar sweetened beverage consumption has been suggested as a risk factor for childhood asthma symptoms. We examined whether the UK Soft Drinks Industry Levy (SDIL), announced in March 2016 and implemented in April 2018, was associated with changes in National Health Service hospital admission rates for asthma in children, 22 months post-implementation of SDIL. We conducted interrupted time series analyses (2012-2020) to measure changes in monthly incidence rates of hospital admissions. Sub-analysis was by age-group (5-9,10-14,15-18 years) and neighbourhood deprivation quintiles. Changes were relative to counterfactual scenarios where the SDIL wasn't announced, or implemented. Overall, incidence rates reduced by 20.9% (95%CI: 29.6-12.2). Reductions were similar across age-groups and deprivation quintiles. These findings give support to the idea that implementation of a UK tax intended to reduce childhood obesity may have contributed to a significant unexpected and additional public health benefit in the form of reduced hospital admissions for childhood asthma.</p

    The UK Soft Drinks Industry Levy and childhood hospital admissions for asthma in England

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    Sugar sweetened beverage consumption has been suggested as a risk factor for childhood asthma symptoms. We examined whether the UK Soft Drinks Industry Levy (SDIL), announced in March 2016 and implemented in April 2018, was associated with changes in National Health Service hospital admission rates for asthma in children, 22 months post-implementation of SDIL. We conducted interrupted time series analyses (2012-2020) to measure changes in monthly incidence rates of hospital admissions. Sub-analysis was by age-group (5-9,10-14,15-18 years) and neighbourhood deprivation quintiles. Changes were relative to counterfactual scenarios where the SDIL wasnā€™t announced, or implemented. Overall, incidence rates reduced by 20.9% (95%CI: 29.6-12.2). Reductions were similar across age-groups and deprivation quintiles. These findings give support to the idea that implementation of a UK tax intended to reduce childhood obesity may have contributed to a significant unexpected and additional public health benefit in the form of reduced hospital admissions for childhood asthma

    High Speed X-ray Phase Contrast Imaging of Energetic Composites under Dynamic Compression

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    Fracture of crystals and frictional heating are associated with the formation of ā€œhot spotsā€ (localized heating) in energetic composites such as polymer bonded explosives (PBXs). Traditional high speed optical imaging methods cannot be used to study the dynamic sub-surface deformation and the fracture behavior of such materials due to their opaque nature. In this study, high speed synchrotron X-ray experiments are conducted to visualize the in situ deformation and the fracture mechanisms in PBXs composed of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) crystals and hydroxyl-terminated polybutadiene binder doped with iron (III) oxide. A modified Kolsky bar apparatus was used to apply controlled dynamic compression on the PBX specimens, and a high speed synchrotron X-ray phase contrast imaging (PCI) setup was used to record the in situ deformation and failure in the specimens. The experiments show that synchrotron X-ray PCI provides a sufficient contrast between the HMX crystals and the doped binder, even at ultrafast recording rates. Under dynamic compression, most of the cracking in the crystals was observed to be due to the tensile stress generated by the diametral compression applied from the contacts between the crystals. Tensile stress driven cracking was also observed for some of the crystals due to the transverse deformation of the binder and superior bonding between the crystal and the binder. The obtained results are vital to develop improved understanding and to validate the macroscopic and mesoscopic numerical models for energetic composites so that eventually hot spot formation can be predicted

    Nitrate enhances skeletal muscle fatty acid oxidation via a nitric oxide-cGMP-PPAR-mediated mechanism.

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    BACKGROUND: Insulin sensitivity in skeletal muscle is associated with metabolic flexibility, including a high capacity to increase fatty acid (FA) oxidation in response to increased lipid supply. Lipid overload, however, can result in incomplete FA oxidation and accumulation of potentially harmful intermediates where mitochondrial tricarboxylic acid cycle capacity cannot keep pace with rates of Ī²-oxidation. Enhancement of muscle FA oxidation in combination with mitochondrial biogenesis is therefore emerging as a strategy to treat metabolic disease. Dietary inorganic nitrate was recently shown to reverse aspects of the metabolic syndrome in rodents by as yet incompletely defined mechanisms. RESULTS: Herein, we report that nitrate enhances skeletal muscle FA oxidation in rodents in a dose-dependent manner. We show that nitrate induces FA oxidation through a soluble guanylate cyclase (sGC)/cGMP-mediated PPARĪ²/Ī“- and PPARĪ±-dependent mechanism. Enhanced PPARĪ²/Ī“ and PPARĪ± expression and DNA binding induces expression of FA oxidation enzymes, increasing muscle carnitine and lowering tissue malonyl-CoA concentrations, thereby supporting intra-mitochondrial pathways of FA oxidation and enhancing mitochondrial respiration. At higher doses, nitrate induces mitochondrial biogenesis, further increasing FA oxidation and lowering long-chain FA concentrations. Meanwhile, nitrate did not affect mitochondrial FA oxidation in PPARĪ±(-/-) mice. In C2C12 myotubes, nitrate increased expression of the PPARĪ± targets Cpt1b, Acadl, Hadh and Ucp3, and enhanced oxidative phosphorylation rates with palmitoyl-carnitine; however, these changes in gene expression and respiration were prevented by inhibition of either sGC or protein kinase G. Elevation of cGMP, via the inhibition of phosphodiesterase 5 by sildenafil, also increased expression of Cpt1b, Acadl and Ucp3, as well as CPT1B protein levels, and further enhanced the effect of nitrate supplementation. CONCLUSIONS: Nitrate may therefore be effective in the treatment of metabolic disease by inducing FA oxidation in muscle.This work was kindly supported by a British Heart Foundation studentship to TA (FS/09/050). AJMu thanks the Research Councils UK for supporting his academic fellowship. LDR is supported by the Medical Research Council-Human Nutrition Research Elsie Widdowson Fellowship. AJMo thanks the Natural Sciences and Engineering Research Council for supporting her postdoctoral fellowship. MF acknowledges support from the Medical Research Council (G1001536). JLG thanks the Medical Research Council (MC_UP_A090_1006), the Biotechnology and Biological Sciences Research Council (BB/H013539/2) and British Heart Foundation for supporting work in his laboratory
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