Allatostatin-A neurons inhibit feeding behavior in adult Drosophila

How the brain translates changes in internal metabolic state or perceived food quality into alterations in feeding behavior remains poorly understood. Studies in Drosophila larvae have yielded information about neuropeptides and circuits that promote feeding, but a peptidergic neuron subset whose activation inhibits feeding in adult flies, without promoting metabolic changes that mimic the state of satiety, has not been identified. Using genetically based manipulations of neuronal activity, we show that activation of neurons (or neuroendocrine cells) expressing the neuropeptide allatostatin A (AstA) inhibits or limits several starvation-induced changes in feeding behavior in adult Drosophila, including increased food intake and enhanced behavioral responsiveness to sugar. Importantly, these effects on feeding behavior are observed in the absence of any measurable effects on metabolism or energy reserves, suggesting that AstA neuron activation is likely a consequence, not a cause, of metabolic changes that induce the state of satiety. These data suggest that activation of AstA-expressing neurons promotes food aversion and/or exerts an inhibitory influence on the motivation to feed and implicate these neurons and their associated circuitry in the mechanisms that translate the state of satiety into alterations in feeding behavior

Environmental Injustice\u27s Impact on Asthma Disparities in NYC

Understanding the social determinants of health is essential when looking at low-income minorities in urban cities. Social determinants of health are conditions in the environment in which people are born, which affects a wide range of health and quality-of-life outcomes. Amongst other determinants, adequate housing can have a significant influence on population health outcomes such as asthma. Zoning inequality negatively and disproportionately impacts the health and the overall quality of life of low-income minorities; zoning is correlated to environmental injustice fueling adverse health effects and health disparities among low-income minority populations. Without the opportunity to receive adequate and affordable housing, communities of color will continue to be burdened by zoning regulations and strained by the environmental injustices–leading them to put their health at risk in hazardous areas. This paper seeks to review the state of the literature on the impact of zoning on environmental injustice, social determinants of health, exposure to indoor and outdoor pollutants and outcomes for asthma, with particular emphasis on how hypersegregation exposes people of color to environmental injustice in urban areas. The literature review shows that differences in neighborhood racial demographics and income result in more exposure to environmental injustice and asthma outcomes in New York City. Under representation and under-maintained public housing in black communities has also been associated with disparities in health outcomes

Characterizing Ferroportin Trafficking in Macrophages During Phagocytosis

Macrophages are important mediators of innate immunity and nutritional immunity via modulation of essential nutrients like iron during bacterial infection. Ferroportin (Fpn), an iron-exporting protein, is found on the plasma membrane of macrophages and, if not modulated during phagocytosis, would transport iron into phagosomes and supply phagocytosed bacteria with iron. Interestingly, the fate of Fpn during phagocytosis and bacterial infection remains unknown. We generated a Fpn-GFP fusion protein and, using fluorescence microscopy, demonstrated that, during phagocytosis in RAW264.7 macrophages, Fpn is removed from phagosomes containing IgG-coated beads or Staphylococcus aureus. Further, Fpn is present on Rab5-containing phagosomes but absent from PI(3)P- and LAMP1-positive phagosomes indicating Fpn removal occurs early during phagosome maturation. Co-localization analysis revealed that markers of cellular recycling pathways, Rab4 and transferrin receptor, do not co-localize with Fpn. Thus, our data support the conclusion that macrophages restrict Fpn residence on phagosomes presumably to prevent iron transport into phagosomes

Supply Chain Management: Fragmented Adoption in Practice

Every day the construction industry develops new ideas and theories toward innovation in increased efficiency and quality for its projects. One method is supply chain management, which focuses on the relationships between partnerships along the supply chain. The theory was first developed in the manufacturing industry and this paper will highlight the reasons behind its fragmented adoption in the construction industry. The overall supply chain typically contains short supply chains that are dismissed upon project completion. Some companies have partially adopted the theory into their work practices but has been unable to fully adopt the theory as a whole. There have been many theories as to why supply chain management has not been able to be fully adopted and the research is aimed to understand the complications associated with it. The complications presented from the research include market conditions, competition and fairness, and workforce limitations. Insights from research gain perspective in how full adoption has been limited, the partial adoption enables partnerships to benefit multiple companies and increase productivity, prevent delays, and reduce additional costs. The challenges that restrict adoption highlight the necessity of said restrictions and cause other issues to rise

Greening rates and photosynthetic development of leaves in C3 and C4 plants

To study chlorophyll development time and overall photosynthetic development in C3 and C4 leaves, seeds were germinated in complete darkness and achlorophyllous leaves were then allowed to develop in lighted conditions. Corn (Zea mays, C4), sorghum (Sorghum bicolor, C4), green bean (Phaseolus vulgaris, C3), broad bean (Vicia faba, C3), and wheat (Triticum aestivum, C3) were investigated for the first ten days of sunlight exposure. Chlorophyll concentration, chlorophyll fluorescence, and CO2 gas exchange measurements were conducted daily on the first leaf that emerged after the embryonic leaves of each plant. The first five days of the experiment, days zero to four in light, had the greatest physiological impact on leaves of etiolated plants as they transitioned from an etiolated to a green state. C3 plants developed chlorophyll and light-harvesting capacity earlier than C4 plants. C3 plants showed faster rates of chlorophyll development compared to C4 plants. The majority of chlorophyll fluorescence parameters measured had developed approximately 80% of their maximum fluorescence in the first five days of light exposure, days five to ten in light had less than a 20% change. However, photochemical quenching (qP), electron transport rate (ETR), photosynthetic carbon assimilation (Photo), stomatal conductance (Cond), and internal CO2 concentration (Ci) were not different between C3 and C4 plants, suggesting that development of gas exchange abilities and capabilities of using carbon from the atmosphere in the processes of photosynthesis were similar between C3 and C4 plants in this experiment

Examining the associations between respiratory sinus arrhythmia in the lab and craving and drinking alcohol in daily life

Alcohol use and abuse is highly prevalent and is related to several serious negative outcomes. Craving, a criterion for alcohol use disorder, is defined as a preoccupation and strong desire to consume alcohol. Craving alcohol can result in an initiation to drink and can lead to a dependency that can be long lasting, which makes it difficult to find the motivation to resist urges to drink. Craving is strongly associated with subsequent use; however, this association is influenced by a number of variables, such as one's ability to self-regulate. Respiratory sinus arrhythmia, an index of parasympathetic outflow to the heart, has been shown to reflect regulatory capacity. In the current study, we collected resting RSA in the lab and self-reported levels of craving and drinking in daily life using ecological momentary assessment. We hypothesized that craving in the moment would be significantly associated with drinking in the moment. We also hypothesized that low resting RSA would result in a higher likelihood of drinking and RSA would moderate the association between craving and drinking in daily life. Twenty-nine participants, who regularly drank alcohol, completed at least seven days of ecological momentary assessment. Results from multilevel analyses provide further support for the association between craving and drinking in daily life; however, RSA was not significantly related to drinking and did not significantly moderate the craving-use association. This is the first study to examine the role of resting RSA as it relates to drinking in daily life

Problems of scale : an O.R./systems approach

The history of analyses of scale and the conventional reductionist methodology are briefly recounted in the first chapter of the thesis. A detailed examination is then made of the theory of economies of scale and its development since the days of Adam Smith. A comprehensive survey shows that the description provided by conventional economic theory is quite unrealistic, and has been dictated by the demands of Neoclassical ideas of equilibrium. It is shown that the available empirical evidence does not easily allow conclusions to be drawn about the optimal scale of plants or enterprises. A simple simulation model then demonstrates that static economies of scale alone are insufficient to determine "optimal" scale - dynamic diseconomies depend upon environmental context and uncertainties of forecasting future demand. The question of technological change is closely bound up with issues of scale. The principle of bounded rationality is applied to deduce some conditions about the nature of technical change using Heiner's "Reliability Condition". The existence of "technological heuristics" (such as a bias in favour of scale-augmenting innovations) is predicted. The argument is illustrated with the use of a computer simulation of successive process innovations in a stylised chenical plant. Conflicting ideas about "optimal" scale in electricity generation, papermaking, brewing and cement manufacture are examined. These views are found to be explicable by borrowing the theory of fourfold cultural bias from the field of social anthropolgy. An Evolutionary Model of Increasing Returns (EMIR) is developed as a computer simulation. This model demonstrates that the restrictions imposed by conventional economic theory can be overcome in a dynamic economic model; economies of scale and technical change are married with plural rationalities to provide a range of findings on industry structure. Market share is found to be a more important determinant of industrial success than economies of scale. EMIR is used to demonstrate the phenomenon of technological "Lock-In"; important policy choices may be determined by small random events as critical points. Market selection mechanisms cannot be relied upon to optimise, whether in scale decisions or other important policy choices. The thesis concludes with a discussion of the use of plural models to go with plural rationalities in the analysis of policy issues

Effects of calcium-rich additives on the small-strain modulus of representative subgrade soils in Missouri

Title from PDF of title page; abstract from research PDF (University of Missouri--Columbia, viewed on June 25, 2014).Calcium rich additives, such as fly ash and lime kiln dust, can improve the mechanical properties of subgrade soils, resulting in better performance and more economical pavement design. Use of calcium-rich additives in Missouri pavement subgrades has been uncommon, due in part to a lack of quantitative data on the benefits derived from stabilization, and the parameters influencing the effectiveness of the stabilization efforts. A need also exists to identify and assess non-destructive testing methods to evaluate the quality of stabilized soils soon after they are placed. Laboratory measurements of small-strain moduli were performed in this study to: (1) quantify the effectiveness of calcium-rich additive stabilization of representative subgrade soils in Missouri, and (2) assess the viability of using stress wave-based, non-destructive testing (NDT) methods for quality assessment of stabilized subgrades. Two representative Missouri subgrade soils, a low plasticity soil (PI=15) and a high plasticity soil (PI=33), were used in this study. These soils were mixed with fly ash (10 percent, 15 percent, and 20 percent by weight) or lime kiln dust (4 percent and 8 percent by weight) and compacted over a range of water contents. Changes in small-strain modulus with time were measured over a period of three to seven days using the free-free resonant column (FFRC) testing method. The results from this study showed large and rapid increases in modulus for most soil-additive combinations. The three-day modulus of the low-plasticity soil more than doubled with the addition of fly ash and more than tripled with the addition of lime kiln dust. However, the results also demonstrated large variability in the effectiveness of additive stabilization. In particular, modulus values of the high plasticity soil increased with the addition of lime kiln dust but showed essentially no effect from fly ash stabilization. Possible reasons for this behavior were developed from a supplemental study of the physical and chemical properties of the soil using particle size analysis, X-ray diffraction, scanning electron microscopy, pH, and cation exchange capacity measurements. Small-strain modulus measurements were also used to evaluate the viability of using stress wave-based velocity measurements in the field for quality assessment. The results of the laboratory measurements showed that the magnitude of very short term (within one hour after compaction) velocity changes of stabilized soil would be detectable using small-strain field measurements (such as seismic surface wave methods). Therefore, wave-based velocity measurements appear to be a viable method for assessing the quality of subgrade stabilization shortly after placement

Global axisymmetric Magnetorotational Instability with density gradients

We examine global incompressible axisymmetric perturbations of a differentially rotating MHD plasma with radial density gradients. It is shown that the standard magnetorotational instability, (MRI) criterion drawn from the local dispersion relation is often misleading. If the equilibrium magnetic field is either purely axial or purely toroidal, the problem reduces to finding the global radial eigenvalues of an effective potential. The standard Keplerian profile including the origin is mathematically ill-posed, and thus any solution will depend strongly on the inner boundary. We find a class of unstable modes localized by the form of the rotation and density profiles, with reduced dependence on boundary conditions.Comment: 22 pages, 5 figure