The feasibility and acceptability of two methods ofsnack portion control in United Kingdom (UK) preschool children: reduction and replacement.

Large portions of high energy dense (HED) snacks are offered to children from a young age and are pervasive in our food environment. This study aimed to explore the feasibility, acceptability, and preliminary efficacy of two strategies of snack portion control: reduction and replacement. Forty-six mother-child dyads aged 22⁻56 months (36.6 ± 9.5 m, 48% female) completed a three-week intervention. In week 1 (baseline) no changes were made to the child's diet; week 2 (acclimation) children received a standardised selection of HED snacks, and in week 3 (intervention) participants were randomly assigned to snack replacement (n = 24) or snack reduction (n = 22). Snack replacement involved swapping HED snacks for fruits and vegetables, whilst snack reduction involved reducing the size of HED snacks by 50%. Food and energy intake were measured using a weighed food diary for four consecutive days. Snack replacement resulted in more positive changes to children's diets; vegetable intake increased (p < 0.01), and total daily energy intake decreased when compared to snack reduction (p < 0.05). Mothers expressed a more favourable attitude to snack replacement, although snack reduction was also well received by mothers. Despite increased preliminary efficacy of snack replacement on dietary intake, both strategies were feasible and acceptable. The current pilot study provides the necessary information to inform the design of future interventions

Effects of chewing on appetite, food intake and gut hormones: A systematic review and meta-analysis

Aim: To conduct a systematic review of the effects of chewing on appetite, food intake and gut hormones, and a meta-analysis of the effects of chewing on self-reported hunger. Objectives: To seek insights into the relationship between chewing, appetite, food intake and gut hormones, and to consider potentially useful recommendations to promote benefits of chewing for weight management. Materials and methods: Papers were obtained from two electronic databases (Medline and Cochrane), from searches of reference lists, and from raw data collected from the figures in the articles. A total of 15 papers were identified that detailed 17 trials. All 15 papers were included in the systematic review; however, a further five studies were excluded from the meta-analysis because appropriate information on hunger ratings was not available. The meta-analysis was conducted on a total of 10 papers that detailed 13 trials. Results: Five of 16 experiments found a significant effect of chewing on satiation or satiety using self-report measures (visual analogue scales, VASs). Ten of 16 experiments found that chewing reduced food intake. Three of five studies showed that increasing the number of chews per bite increased relevant gut hormones and two linked this to subjective satiety. The meta-analysis found evidence of both publication bias and between study heterogeneity (IA2=93.4%, tau2=6.52, p<0.001) which decreased, but remained, when covariates were considered. Analysis of the heterogeneity found a substantial effect of the fasting period where the duration of fasting influenced the decrease in hunger due to chewing. Prolonged mastication significantly reduces self-reported hunger levels (hunger: -2.31 VAS point, 95% CI [-4.67, -1.38], p<0.001). Conclusions: Evidence currently suggests that chewing may decrease self-reported hunger and food intake, possibly through alterations in gut hormone responses related to satiety. Although preliminary, the results identify a need for additional research in the area. Focused, uniform, experimental designs are required to clearly understand the relationships that exist between mastication, appetite, satiety, food intake and, ultimately, body weight

Simulating rewetting events in intermittent rivers and ephemeral streams: a global analysis of leached nutrients and organic matter

Climate change and human pressures are changing the global distribution and extent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico‐chemical changes (preconditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experimentally simulated, under standard laboratory conditions, rewetting of leaves, riverbed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative characteristics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dissolved substances during rewetting events (56‐98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contributed most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached organic matter. The opposite pattern was found in the arid zone. Environmental variables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached substances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying events

Simulating rewetting events in intermittent rivers and ephemeral streams: A global analysis of leached nutrients and organic matter

Climate change and human pressures are changing the global distribution and the ex‐ tent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico‐chemical changes (precon‐ ditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experi‐ mentally simulated, under standard laboratory conditions, rewetting of leaves, river‐ bed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative character‐ istics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dis‐ solved substances during rewetting events (56%–98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contrib‐ uted most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached OM. The opposite pattern was found in the arid zone. Environmental vari‐ ables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached sub‐ stances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying event

International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.

Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist

The Value of Failure in Science: The Story of Grandmother Cells in Neuroscience

The annals of science are filled with successes. Only in footnotes do we hear about the failures, the cul-de-sacs, and the forgotten ideas. Failure is how research advances. Yet it hardly features in theoretical perspectives on science. That is a mistake. Failures, whether clear-cut or ambiguous, are heuristically fruitful in their own right. Thinking about failure questions our measures of success, including the conceptual foundations of current practice, that can only be transient in an experimental context. This article advances the heuristics of failure analysis, meaning the explicit treatment of certain ideas or models as failures. The value of failures qua being a failure is illustrated with the example of grandmother cells; the contested idea of a hypothetical neuron that encodes a highly specific but complex stimulus, such as the image of one’s grandmother. Repeatedly evoked in popular science and maintained in textbooks, there is sufficient reason to critically review the theoretical and empirical background of this idea

The feasibility and acceptability of two methods of snack portion control in United Kingdom (UK) preschool children:reduction and replacement

Large portions of high energy dense (HED) snacks are offered to children from a young age and are pervasive in our food environment. This study aimed to explore the feasibility, acceptability, and preliminary efficacy of two strategies of snack portion control: reduction and replacement. Forty-six mother-child dyads aged 22–56 months (36.6 ± 9.5 m, 48% female) completed a three-week intervention. In week 1 (baseline) no changes were made to the child’s diet; week 2 (acclimation) children received a standardised selection of HED snacks, and in week 3 (intervention) participants were randomly assigned to snack replacement (n = 24) or snack reduction (n = 22). Snack replacement involved swapping HED snacks for fruits and vegetables, whilst snack reduction involved reducing the size of HED snacks by 50%. Food and energy intake were measured using a weighed food diary for four consecutive days. Snack replacement resulted in more positive changes to children’s diets; vegetable intake increased (p &lt; 0.01), and total daily energy intake decreased when compared to snack reduction (p &lt; 0.05). Mothers expressed a more favourable attitude to snack replacement, although snack reduction was also well received by mothers. Despite increased preliminary efficacy of snack replacement on dietary intake, both strategies were feasible and acceptable. The current pilot study provides the necessary information to inform the design of future interventions