The Growing Influence of Immigrants on American Politics

Reviewing: Tom K. Wong, The Politics of Immigration: Partisanship, Demographic Change, and American National Identit

Effects of prostaglandin E(2 )on the electrical properties of thermally classified neurons in the ventromedial preoptic area of the rat hypothalamus

BACKGROUND: Physiological and morphological evidence suggests that activation of the ventromedial preoptic area of the hypothalamus (VMPO) is an essential component of an intravenous LPS-dependent fever. In response to the endogenous pyrogen prostaglandin E(2 )(PGE(2)), the majority of temperature insensitive neurons in the VMPO show an increase in firing rate, while warm sensitive neurons are inhibited. We have hypothesized that these PGE(2 )dependent effects on firing rate are due to changes in the inherent electrical properties of VMPO neurons, which are regulated by the activity of specific ionic currents. RESULTS: To characterize the electrical properties of VMPO neurons, whole-cell recordings were made in tissue slices from male Sprague-Dawley rats. Our results indicate that PGE(2 )dependent firing rate responses were not the result of changes in resting membrane potential, action potential amplitude and duration, or local synaptic input. However, PGE(2 )reduced the input resistance of all VMPO neurons, while increasing the excitability of temperature insensitive neurons and decreasing the excitability of warm sensitive neurons. In addition, the majority of temperature insensitive neurons responded to PGE(2 )with an increase in the rate of rise of the depolarizing prepotential that precedes each action potential. This response to PGE(2 )was reversed for warm sensitive neurons, in which the prepotential rate of rise decreased. CONCLUSION: We would therefore suggest that PGE(2 )is having an effect on the ionic currents that regulate firing rate by controlling how fast membrane potential rises to threshold during the prepotential phase of the action potential

Distribution and incidence of viruses in Irish seed potato crops

peer-reviewedVirus diseases are of key importance in potato production and in particular for the production of disease-free potato seed. However, there is little known about the frequency and distribution of potato virus diseases in Ireland. Despite a large number of samples being tested each year, the data has never been collated either within or across years. Information from all known potato virus testing carried out in the years 2006–2012 by the Department of Agriculture Food and Marine was collated to give an indication of the distribution and incidence of potato virus in Ireland. It was found that there was significant variation between regions, varieties, years and seed classes. A definition of daily weather data suitable for aphid flight was developed, which accounted for a significant proportion of the variation in virus incidence between years. This use of weather data to predict virus risk could be developed to form the basis of an integrated pest management approach for aphid control in Irish potato crops

Separation and Purification of Mineral Salts from Spacecraft Wastewater Processing via Electrostatic Beneficiation

Electrostatic separation is a class of material processing technologies commonly used for the sorting of coarse mixtures by means of electrical forces acting on charged or polarized particles. Most if not all of the existing tribo-electrostatic separators had been initially developed for mineral ores beneficiation. It is a well-known process that has been successfully used to separate coal from minerals. Potash (potassium) enrichment where underground salt mines containing large amounts of sodium is another use of this techno logy. Through modification this technology can be used for spacecraft wastewater brine beneficiation. This will add in closing the gap be~een traveling around Earth's Gravity well and long-term space explorations. Food has been brought on all man missions, which is why plant growth for food crops continues to be of interest to NASA. For long-term mission considerations food productions is one of the top priorities. Nutrient recovery is essential for surviving in or past low earth orbit. In our advance bio-regenerative process instead of nitrogen gas produced; soluble nitrate salts that can be recovered for plant fertilizer would be produced instead. The only part missing is the beneficiation of brine to separate the potassium from the sodium. The use of electrostatic beneficiation in this experiment utilizes the electrical charge differences between aluminum and dried brine by surface contact. The helixes within the aluminum tribocharger allows for more surface contact when being agitated. When two materials are in contact, the material with the highest affinity for electrons becomes negatively charged, while the other becomes positively charged. This contact exchange of charge may cause the particles to agglomerate depending on their residence time within the tribocharger, compromising the efficiency of separation. The aim of this experiment is to further the development in electrostatic beneficiation by optimizing the separation of ersatz and possibly real wastewater brine residues. In doing so, ideally it will yield a high potassium enrichment for use in spacecraft plant systems

Understanding the Delayed-Keyword Effect on Metacomprehension Accuracy

The typical finding from research on metacomprehension is that accuracy is quite low. However, recent studies have shown robust accuracy improvements when judgments follow certain generation tasks (summarizing or keyword listing), but only when these tasks are performed at a delay rather than immediately after reading (Thiede & Anderson, 2003; Thiede, Anderson & Therriault, 2003). The delayed and immediate conditions in these past studies confounded the delay between reading and generation tasks with other task lags, such as the lag between multiple generation tasks and the lag between generation tasks and judgments. The first two experiments disentangle these confounded manipulations and provide clear evidence that the delay between reading and keyword generation is the only lag critical to improving metacomprehension accuracy. The third and fourth experiments show that not all delayed tasks will produce improvements and suggest that delayed generative tasks provide diagnostic cues about comprehension that are necessary for improving metacomprehension accuracy

Racial Differences in Inequality Aversion: Evidence from Real World Respondents in the Ultimatum Game

The distinct historical and cultural experiences of American blacks and whites may influence whether members of those groups perceive a particular exchange as fair. We investigate racial differences in fairness standards using preferences for equal treatment in the ultimatum game, where responders choose to allow a proposed division of a monetary amount or to block it. Although previous research has studied group differences in the ultimatum game, no study has been able to examine these across races in America. We use a sample of over 1600 blacks and whites drawn from the universe of registered voters in three states and merged with information on neighborhood income and racial composition. We experimentally vary proposed divisions as well as the implied race of the ultimatum game proposer. We find no overall racial differences in acceptance rates or aversion to unequal divisions. However, we uncover racial differences in the response to pecuniary returns conditional on inequality of the division. This is driven by the lowest income group in our sample, which represents the 10th percentile of the black income distribution. The racial differences are robust across gender and age groups. We also find that blacks are more sensitive to unfair proposals from other blacks.

Pharmacotherapy for neonatal seizures: current knowledge and future perspectives

Seizures are the most common neurological emergencies in the neonatal period and are associated with poor neurodevelopmental outcomes. Seizures affect up to five per 1000 term births and population-based studies suggest that they occur even more frequently in premature infants. Seizures are a sign of an underlying cerebral pathology, the most common of which is hypoxic-ischaemic encephalopathy in term infants. Due to a growing body of evidence that seizures exacerbate cerebral injury, effective diagnosis and treatment of neonatal seizures is of paramount importance to reduce long-term adverse outcomes. Electroencephalography is essential for the diagnosis of seizures in neonates due to their subtle clinical expression, non-specific neurological presentation and a high frequency of electro-clinical uncoupling in the neonatal period. Hypoxic-ischaemic encephalopathy may require neuroprotective therapeutic hypothermia, accompanying sedation with opioids, anticonvulsant drugs or a combination of all of these. The efficacy, safety, tolerability and pharmacokinetics of seven anticonvulsant drugs (phenobarbital, phenytoin, levetiracetam, lidocaine, midazolam, topiramate and bumetanide) are reviewed. This review is focused only on studies reporting electrographically confirmed seizures and highlights the knowledge gaps that exist in optimal treatment regimens for neonatal seizures. Randomised controlled trials are needed to establish a safe and effective treatment protocol for neonatal seizures

Seeing an exercise as a single mathematical object: using variation to structure sense-making

In this theoretical paper we take an exercise to be a collection of procedural questions or tasks. It can be useful to treat such an exercise as a single object, with individual questions seen as elements in a mathematically and pedagogically structured set. We use the notions of 'dimensions of possible variation' and 'range of permissible change', derived from Ference Marton, to discuss affordances and constraints of some sample exercises. This gives insight into the potential pedagogical role of exercises, and shows how exercise analysis and design might contribute to hypotheses about learning trajectories. We argue that learners' response to an exercise has something in common with modeling that we might call 'micro-modeling', but we resort to a more inclusive description of mathematical thinking to describe learners' possible responses to a well-planned exercise. Finally we indicate how dimensions of possible variation inform the design and use of an exercise