Fetal liver blood flow distribution: role in human developmental strategy to prioritize fat deposition versus brain development

Among primates, human neonates have the largest brains but also the highest proportion of body fat. If placental nutrient supply is limited, the fetus faces a dilemma: should resources be allocated to brain growth, or to fat deposition for use as a potential postnatal energy reserve? We hypothesised that resolving this dilemma operates at the level of umbilical blood distribution entering the fetal liver. In 381 uncomplicated pregnancies in third trimester, we measured blood flow perfusing the fetal liver, or bypassing it via the ductus venosus to supply the brain and heart using ultrasound techniques. Across the range of fetal growth and independent of the mother's adiposity and parity, greater liver blood flow was associated with greater offspring fat mass measured by dual-energy X-ray absorptiometry, both in the infant at birth (r = 0.43, P<0.001) and at age 4 years (r = 0.16, P = 0.02). In contrast, smaller placentas less able to meet fetal demand for essential nutrients were associated with a brain-sparing flow pattern (r = 0.17, p = 0.02). This flow pattern was also associated with a higher degree of shunting through ductus venosus (P = 0.04). We propose that humans evolved a developmental strategy to prioritize nutrient allocation for prenatal fat deposition when the supply of conditionally essential nutrients requiring hepatic inter-conversion is limited, switching resource allocation to favour the brain if the supply of essential nutrients is limited. Facilitated placental transfer mechanisms for glucose and other nutrients evolved in environments less affluent than those now prevalent in developed populations, and we propose that in circumstances of maternal adiposity and nutrient excess these mechanisms now also lead to prenatal fat deposition. Prenatal developmental influences play important roles in the human propensity to deposit fa

Climate vulnerability assessment for Pacific salmon and steelhead in the California Current Large Marine Ecosystem.

Major ecological realignments are already occurring in response to climate change. To be successful, conservation strategies now need to account for geographical patterns in traits sensitive to climate change, as well as climate threats to species-level diversity. As part of an effort to provide such information, we conducted a climate vulnerability assessment that included all anadromous Pacific salmon and steelhead (Oncorhynchus spp.) population units listed under the U.S. Endangered Species Act. Using an expert-based scoring system, we ranked 20 attributes for the 28 listed units and 5 additional units. Attributes captured biological sensitivity, or the strength of linkages between each listing unit and the present climate; climate exposure, or the magnitude of projected change in local environmental conditions; and adaptive capacity, or the ability to modify phenotypes to cope with new climatic conditions. Each listing unit was then assigned one of four vulnerability categories. Units ranked most vulnerable overall were Chinook (O. tshawytscha) in the California Central Valley, coho (O. kisutch) in California and southern Oregon, sockeye (O. nerka) in the Snake River Basin, and spring-run Chinook in the interior Columbia and Willamette River Basins. We identified units with similar vulnerability profiles using a hierarchical cluster analysis. Life history characteristics, especially freshwater and estuary residence times, interplayed with gradations in exposure from south to north and from coastal to interior regions to generate landscape-level patterns within each species. Nearly all listing units faced high exposures to projected increases in stream temperature, sea surface temperature, and ocean acidification, but other aspects of exposure peaked in particular regions. Anthropogenic factors, especially migration barriers, habitat degradation, and hatchery influence, have reduced the adaptive capacity of most steelhead and salmon populations. Enhancing adaptive capacity is essential to mitigate for the increasing threat of climate change. Collectively, these results provide a framework to support recovery planning that considers climate impacts on the majority of West Coast anadromous salmonids

Molecular dynamics of membrane proteins.

Understanding the dynamics of the membrane protein rhodopsin will have broad implications for other membrane proteins and cellular signaling processes. Rhodopsin (Rho) is a light activated G-protein coupled receptor (GPCR). When activated by ligands, GPCRs bind and activate G-proteins residing within the cell and begin a signaling cascade that results in the cell's response to external stimuli. More than 50% of all current drugs are targeted toward G-proteins. Rho is the prototypical member of the class A GPCR superfamily. Understanding the activation of Rho and its interaction with its Gprotein can therefore lead to a wider understanding of the mechanisms of GPCR activation and G-protein activation. Understanding the dark to light transition of Rho is fully analogous to the general ligand binding and activation problem for GPCRs. This transition is dependent on the lipid environment. The effect of lipids on membrane protein activity in general has had little attention, but evidence is beginning to show a significant role for lipids in membrane protein activity. Using the LAMMPS program and simulation methods benchmarked under the IBIG program, we perform a variety of allatom molecular dynamics simulations of membrane proteins

Physicochemical Characterization of Zeolites SSZ-26 and SSZ-33

Detailed characterization of zeolites SSZ-26 and SSZ-33 is presented and includes data from adsorption experiments, X-ray powder diffraction (XRD), electron diffraction (ED), and high-resolution electron microscopy (HREM). Simulated XRD patterns and HREM images of the proposed structures agree very well with all the experimental data. These zeolites are the first synthetic high-silica molecular sieves to contain a three-dimensional pore system comprised of intersecting 10- and 12-ring pores. The structures of SSZ-26 and SSZ-33 are compared to the structures of known zeolites, and the relationships between the geometry of the structure-directing agents used in the synthesis of SSZ-26 and the geometry of the pores are analyzed using energy minimization calculations. Several hypothetical zeolite structures are derived based on the proposed models for SSZ-26 and SSZ-33. SSZ-26 and SSZ-33 are the first examples of molecular sieves whose multidimensional pore systems have been formed by the purposeful design of their structure-directing agents

Physicochemical Characterization of Zeolites SSZ-26 and SSZ-33

Detailed characterization of zeolites SSZ-26 and SSZ-33 is presented and includes data from adsorption experiments, X-ray powder diffraction (XRD), electron diffraction (ED), and high-resolution electron microscopy (HREM). Simulated XRD patterns and HREM images of the proposed structures agree very well with all the experimental data. These zeolites are the first synthetic high-silica molecular sieves to contain a three-dimensional pore system comprised of intersecting 10- and 12-ring pores. The structures of SSZ-26 and SSZ-33 are compared to the structures of known zeolites, and the relationships between the geometry of the structure-directing agents used in the synthesis of SSZ-26 and the geometry of the pores are analyzed using energy minimization calculations. Several hypothetical zeolite structures are derived based on the proposed models for SSZ-26 and SSZ-33. SSZ-26 and SSZ-33 are the first examples of molecular sieves whose multidimensional pore systems have been formed by the purposeful design of their structure-directing agents

The assignment of moral status: Age-related differences in the use of three mental capacity criteria

This study examined children's and young adults' use of three mental capacity criteria for treating an entity as one to which moral subjects have moral obligations, that is, as having moral status. In line with philosophical theorizing, these criteria were the capacity to (1) perceive; (2) suffer; and (3) think. In this study, 116 respondents aged 9 to 18 years old gave moral judgments and guilt and shame attributions in response to stories about perpetrators whose behaviour negatively affected entities with different mental capacities. The moral judgments revealed that 9-year-old children assigned moral status primarily on the basis of the victimized entity's ability to suffer. Eleven-year-old children also used the ability to suffer, but they assigned additional moral status when the victimized entity was able to perceive. Young adults also used perception as a criterion, but they assigned additional moral status when the victimized entity was simultaneously able to suffer and able to think. When compared to their moral judgments, the moral emotion attributions of respondents of all age groups were more strongly affected by the victimized entity's ability to think. © 2008 The British Psychological Society

Cacao seeds are a "Super Fruit": A comparative analysis of various fruit powders and products

<p>Abstract</p> <p>Background</p> <p>Numerous popular media sources have developed lists of "Super Foods" and, more recently, "Super Fruits". Such distinctions often are based on the antioxidant capacity and content of naturally occurring compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of <it>the Theobroma cacao </it>tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived from fruits commonly considered "Super Fruits".</p> <p>Results</p> <p>Various fruit powders and retail fruit products were obtained and analyzed for antioxidant capacity (ORAC (μM TE/g)), total polyphenol content (TP (mg/g)), and total flavanol content (TF (mg/g)). Among the various powders that were tested, cocoa powder was the most concentrated source of ORAC and TF. Similarly, dark chocolate was a significantly more concentrated source of ORAC and TF than the fruit juices.</p> <p>Conclusions</p> <p>Cocoa powder and dark chocolate had equivalent or significantly greater ORAC, TP, and TF values compared to the other fruit powders and juices tested, respectively. Cacao seeds thus provide nutritive value beyond that derived from their macronutrient composition and appear to meet the popular media's definition of a "Super Fruit".</p

Evaluation Research and Institutional Pressures: Challenges in Public-Nonprofit Contracting

This article examines the connection between program evaluation research and decision-making by public managers. Drawing on neo-institutional theory, a framework is presented for diagnosing the pressures and conditions that lead alternatively toward or away the rational use of evaluation research. Three cases of public-nonprofit contracting for the delivery of major programs are presented to clarify the way coercive, mimetic, and normative pressures interfere with a sound connection being made between research and implementation. The article concludes by considering how public managers can respond to the isomorphic pressures in their environment that make it hard to act on data relating to program performance.This publication is Hauser Center Working Paper No. 23. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers

A [Ce21] Keplerate

The solvothermal reaction between Ce(NO3)3·6H2O, 2-amino-isobutyric acid, 2-hydroxy-1-naphthaldehyde and 2-amino-2-methyl-1,3-propanediol in MeOH, in the presence of base, leads to the formation of a unique [CeIV13Ce III8] keplerate cage