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Gestational diabetes mellitus is associated with a significantly increased risk of later type 2 diabetes (T2DM) and cardiovascular disease (CVD). Post-natal interventions aim to reduce this risk by addressing diet and lifestyle factors and frequently focus on restricting energy or macronutrient intake. With increased interest in the role of complete dietary patterns in the prevention of cardiometabolic disease, we sought to evaluate what is known about the role of dietary patterns in reducing cardiometabolic risk in women with previous GDM. A systematic search was conducted to identify studies relating to dietary pattern and cardiometabolic parameters in women with a history of GDM. The search criteria returned 6014 individual studies. In total, 71 full texts were reviewed, with 24 studies included in the final review. Eleven individual dietary patterns were identified, with the Alternative Health Eating Index (AHEI), Mediterranean diet (MD), and low glycaemic index (GI) as the most commonly featured dietary patterns. Relevant reported outcomes included incident T2DM and glucose tolerance parameters, as well as several cardiovascular risk factors. Dietary patterns which have previously been extensively demonstrated to reduce the risk of cardiovascular and metabolic disorders in the general population, including AHEI, MD, and DASH, were found to be associated with a reduction in the incidence of T2DM, hypertension, and additional risk factors for cardiometabolic disease in women with a history of GDM. Notable gaps in the literature were identified, including the relationship between dietary patterns and incident CVD, as well as the relationship between a low GI diet and the development of T2DM in this population.

As topology representing networks, the Cumulative ADJacency graph CADJ and its symmetric version $${{\text{CONN}}} = {\text{CADJ}} + {\text{CADJ}}^T$$ Tasdemir and Merenyi (IEEE Trans Neural Netw 20(4): 549–562, 2009), can be utilized as inputs to graph-based clustering (GBC) paradigms for partitioning the learned prototypes of a vector quantizer. To express complex data faithfully, CADJ must typically be pruned (thresholded, or made sparse) to be most effective as an input to GBC routines, whether they be algorithmic or driven by human assessment. This work, given in two parts, develops a formal framework for CADJ pruning as a preprocessing (sparsifying) step to improve CADJ’s use in any GBC routine. That is, rather than advocating a particular GBC method, our goal is development of sensible logic for creating sparse CADJ inputs to the entire family of GBC methods. Part 1 defines an overall quality measure for each CADJ edge by extending lines of reasoning used successfully in the past to prune CONN graphs. Part 2 introduces a Bayesian Dirichlet-multinomial (DM) model of CADJ edge weights with an intelligent prior constructed through analysis of the Voronoi tessellation generated by the vector quantization. The DM likelihood offers an internal assessment of information loss resulting from iterative CADJ edge removal, which is used to determine an optimal stopping criterion for the pruning process. We show that DM-Pruned CADJ graphs lead to GBCs comparable to the best previously achieved on highly structured real data.

We study the formation, evolution and collapse of dense cores by tracking structures in a magnetohydrodynamic simulation of a star-forming cloud. We identify cores using the dendrogram algorithm and utilize machine learning techniques, including Neural Gas prototype learning and Fuzzy $c$-means clustering, to analyze the density and velocity dispersion profiles of cores together with six bulk properties. We produce a 2-d visualization using a Uniform Manifold Approximation and Projection (UMAP), which facilitates the connection between physical properties and three partially-overlapping phases: i) unbound turbulent structures (Phase I), ii) coherent cores that have low turbulence (Phase II), and iii) bound cores, many of which become protostellar (Phase III). Within Phase II we identify a population of long-lived coherent cores that reach a quasi-equilibrium state. Most prestellar cores form in Phase II and become protostellar after evolving into Phase III. Due to the turbulent cloud environment, the initial core properties do not uniquely predict the eventual evolution, i.e., core evolution is stochastic, and cores follow no one evolutionary path. The phase lifetimes are 1.0$\pm$0.1$\times$10$^5$ yr, 1.3$\pm$0.2$\times$10$^5$ yr, and 1.8$\pm$0.3$\times$10$^5$ yr for Phase I, II, and III, respectively. We compare our results to NH$_3$ observations of dense cores. Known coherent cores predominantly map into Phase II, while most turbulent pressure-confined cores map to Phase I or III. We predict that a significant fraction of observed starless cores have unresolved coherent regions and that $\gtrsim 20$% of observed starless cores will not form stars. Measurements of core radial profiles, in addition to the usual bulk properties, will enable more accurate predictions of core evolution., Comment: 26 pages, 16 figures. Accepted to MNRAS

Classical ecology provides principles for construction and function of biological communities, but to what extent these apply to the animal-associated microbiota is just beginning to be assessed. Here, we investigated the influence of several well-known ecological principles on animal-associated microbiota by characterizing gut microbial specimens from bilaterally symmetrical animals (Bilateria) ranging from flies to whales. A rigorously vetted sample set containing 265 specimens from 64 species was assembled. Bacterial lineages were characterized by 16S rRNA gene sequencing. Previously published samples were also compared, allowing analysis of over 1,098 samples in total. A restricted number of bacterial phyla was found to account for the great majority of gut colonists. Gut microbial composition was associated with host phylogeny and diet. We identified numerous gut bacterial 16S rRNA gene sequences that diverged deeply from previously studied taxa, identifying opportunities to discover new bacterial types. The number of bacterial lineages per gut sample was positively associated with animal mass, paralleling known species-area relationships from island biogeography and implicating body size as a determinant of community stability and niche complexity. Samples from larger animals harbored greater numbers of anaerobic communities, specifying a mechanism for generating more-complex microbial environments. Predictions for species/abundance relationships from models of neutral colonization did not match the data set, pointing to alternative mechanisms such as selection of specific colonists by environmental niche. Taken together, the data suggest that niche complexity increases with gut size and that niche selection forces dominate gut community construction., IMPORTANCE The intestinal microbiome of animals is essential for health, contributing to digestion of foods, proper immune development, inhibition of pathogen colonization, and catabolism of xenobiotic compounds. How these communities assemble and persist is just beginning to be investigated. Here we interrogated a set of gut samples from a wide range of animals to investigate the roles of selection and random processes in microbial community construction. We show that the numbers of bacterial species increased with the weight of host organisms, paralleling findings from studies of island biogeography. Communities in larger organisms tended to be more anaerobic, suggesting one mechanism for niche diversification. Nonselective processes enable specific predictions for community structure, but our samples did not match the predictions of the neutral model. Thus, these findings highlight the importance of niche selection in community construction and suggest mechanisms of niche diversification.

The Norway rat (Rattus norvegicus) is a key pest species globally and responsible for seasonal outbreaks of the zoonotic bacterial disease leptospirosis in the tropics. The city of Salvador, Brazil, has seen recent and dramatic increases in human population residing in slums, where conditions foster high rat density and increasing leptospirosis infection rates. Intervention campaigns have been used to drastically reduce rat numbers. In planning these interventions, it is important to define the eradication units ‐ the spatial scale at which rats constitute continuous populations and from where rats are likely recolonizing, post‐intervention. To provide this information, we applied spatial genetic analyses to 706 rats collected across Salvador and genotyped at 16 microsatellite loci. We performed spatially explicit analyses and estimated migration levels to identify distinct genetic units and landscape features associated with genetic divergence at different spatial scales, ranging from valleys within a slum community to city‐wide analyses. Clear genetic breaks exist between rats not only across Salvador but also between valleys of slums separated by

Piwi-interacting RNAs (piRNAs) guide Piwi Argonautes to suppress transposon activity in animal gonads. Known piRNA populations are extremely complex, with millions of individual sequences present in a single organism. Despite this complexity, specific Piwi proteins incorporate piRNAs with distinct nucleotide- and transposon strand-biases (antisense or sense) of unknown origin. Here, we examined the contribution of structural domains in Piwi proteins toward defining these biases. We report the first crystal structure of the MID domain from a Piwi Argonaute and use docking experiments to show its ability to specify recognition of 5′ uridine (1U-bias) of piRNAs. Mutational analyses reveal the importance of 5′ end-recognition within the MID domain for piRNA biogenesis in vivo. Finally, domain-swapping experiments uncover an unexpected role for the MID-PIWI module of a Piwi protein in dictating the transposon strand-orientation of its bound piRNAs. Our work identifies structural features that allow distinguishing individual Piwi members during piRNA biogenesis.

Researchers have consistently linked neuroticism to career indecision; however, other personality traits have been inconsistent predictors despite sound theoretical arguments. Similarly, little research has examined a trait-based analysis of the relationship between vocational interests and career indecision. The purpose of the current study was to evaluate the structure of career indecision and to examine the prediction of this construct as both a unidimensional and multidimensional construct. Results suggest that career indecision is multifaceted and that both personality and vocational interests are more strongly related to career indecision than has been suggested by past research. Furthermore, consideration of this multidimensional nature can explain past inconsistencies in the relationships between indecision and personality.

Questions: What are the long-term patterns of wildfire occurrence and gap dynamics in an old-growth deciduous forest? Are there temporal patterns in fire and gap dynamics over the last ca. 300 yrs? How is drought related to fire occurrence? Are there temporal interactions between gap dynamics and fire? Location: Lilley Cornett Woods Appalachian Research Station, Southeastern Kentucky, USA. LCW; 37°05′ N, 83°00′ W. Methods: We cross-dated and analysed annually-resolved tree-ring data from 35 tree cross-sections in an old-growth deciduous forest to reconstruct historical fire and canopy disturbance and explore connections among these processes. Canopy disturbance patterns as indicated by tree growth release within this collection [fire history collection: (FHC)] were compared to cores from 26 trees collected in 1983 for the purposes of climate reconstruction [climate collection: (CC)]. Results: Initiation dates in the FHC ranged from ca. 1670 to 1925. Thirty-three fire scars were identified from 1678 to 1956. The mean interval between fire events was 9.3 yrs, and there were many more fires after 1800 than before that date. Gap dynamics, as reconstructed through growth release detection, were relatively constant through the FHC record and were supported by a similar result in the CC. The mean number of years between detected release events was 5.2 yrs. Many individual trees, and the mean growth chronology for the FHC, indicate that many oak trees exhibit growth release after long periods of suppression and, after a final release, exhibit a step-change in growth rate suggesting canopy accession. Conclusions: Fire and gap dynamics occurred through much of the last ca. 350 yrs in this old-growth forest. There was not evidence to support that these two processes were temporally linked – gap dynamics were ostensibly independent of fire occurrence. Even so, we posit that these two processes may have a synergistic effect on long-term dynamics, wherein fire ‘filters’ the seedling pool and gap openings provide canopy accession opportunities. We also note several instances where release events are associated with stand-wide growth increases suggesting large-scale canopy accession. These events could influence the overstorey composition of the forest for centuries.

The use of an air curtain blowing across the aperture of a falling-particle receiver has been proposed to mitigate convective heat losses and to protect the flow of particles from external winds. This paper presents experimental and numerical studies that evaluate the impact of an air curtain on the performance of a falling particle receiver. Unheated experimental studies were performed to evaluate the impact of various factors (particle size, particle mass flow rate, particle release location, air-curtain flow rate, and external wind) on particle flow, stability, and loss through the aperture. Numerical simulations were performed to evaluate the impact of an air curtain on the thermal efficiency of a falling particle receiver at different operating temperatures. Results showed that the air curtain reduced particle loss when particles were released near the aperture in the presence of external wind, but the presence of the air curtain did not generally improve the flow characteristics and loss of the particles for other scenarios. Numerical results showed that the presence of an air curtain could reduce the convective heat losses, but only at higher temperatures (>600°C) when buoyant hot air leaving the aperture was significant.Copyright © 2014 by ASME

Consistent with neo-liberal human capital learning assumptions most U.S. schooling jurisdictions now include career education curricula (Hyslop-Margison, 2005). Although career preparatory programs, when appropriately designed, may qualify as education and respect democratic learning principles, there is a troubling tendency for these programs to pursue instrumental, indoctrinatory and ideologically based practices. A concomitant concern arises, then, on how these programs impact on the preparation of democratic citizens.

Background Parents and carers of children with eczema often underuse emollient therapy, essential to repairing and protecting the defective skin barrier in atopic eczema. Educational interventions delivered by specialist dermatology nurses in hospital settings have been shown to improve emollient use and reduce symptoms of atopic eczema, but benefits of community-based interventions are uncertain. Support and information about appropriate care may often be inadequate for patients and carers in the community. Methods A multifaceted educational support programme was evaluated as a method of increasing emollient use and reducing atopic eczema in children. Support provided for parents and carers included an educational DVD, online daily diary and telephone helpline. The before and after study included 136 British children and their parents, providing baseline and 12 week follow-up data while receiving the programme. Measures included emollient use, POEM and PEST scores, and cost of care. Results Average emollient use increased by 87.6 g (95% CI: 81.9 to 119.5 g, p = 0.001) from baseline with the change being immediate and persistent. The POEM score reduced on average by 5.38 (95% CI: 4.36 to 6.41, p = 0.001), a 47% reduction from baseline. Similarly the PEST score reduced on average by 0.61 (95% CI: 0.47 to 0.75, p = 0.001), a 48% reduction from baseline. Sleep disturbance was reduced by 1.27 nights per week (95% CI: 0.85 to 1.68, p = 0.001) and parental feeling of control improved by 1.32 points (95% CI: 1.16 to 1.48, p = 0.001). From the NHS perspective, the programme was cost neutral overall within the study period. Conclusion A community-based multifaceted educational support programme greatly increased emollient use, reducing symptoms of atopic eczema and general practitioner contacts, without increasing cost. Significant benefits may accrue to the families and carers of children with atopic eczema due to improved sleep patterns and greater feeling of control. PEST, a new simple measure of acute and remitting atopic eczema severity designed to help parents and children to monitor and manage eczema, merits further evaluation.