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What does the rise and election of Donald J. Trump as president mean for the future of conservatism? Republican elites continue to argue about whether Trump is changing the definition of conservatism for better or worse, although many Republicans seem content to let him shape the issues, direction, and brand of the traditional party of conservatism. We examine the ideological characteristics of different groups of Republican voters across three types of ideology: symbolic, operational, and conceptual. We find distinct differences between Republicans who consistently supported Trump and other groups that either supported him in the general election only and those who never supported him. The Never Trump camp stands out as a group that is less symbolically and operationally conservative but also better able to articulate what it means to be a conservative than do Trump’s core supporters, who look very much the opposite. These results suggest a contemporary Republican Party that is far from unified in what it means to be a conservative.
Are people conservative (liberal) because they are Republicans
(Democrats)? Or is it the reverse: people are Republicans
(Democrats) because they are conservatives (liberals)? Though much
has been said about this long-standing question, it is difficult to
test because the concepts are nearly impossible to disentangle in
modern America. Ideology and partisanship are highly correlated,
only growing more so over time. However, the election of President
Trump presents a unique opportunity to disentangle party attachment
from ideological commitment. Using a research design that employs
actual “conservative” and “liberal” policy statements from President
Trump, we find that low-knowledge respondents, strong Republicans,
Trump-approving respondents, and self-described conservatives are
the most likely to behave like party loyalists by accepting the
Trump cue—in either a liberal or conservative direction. These
results suggest that there are a large number of party loyalists in
the United States, that their claims to being a self-defined
conservative are suspect, and that group loyalty is the stronger
motivator of opinion than are any ideological principles.
Mycobacterium paratuberculosis is the known cause of Johne's disease in cattle and has been implicated as a cause of Crohn's disease in humans. Concern has been expressed that the organism, which is excreted in milk and faeces of infected cattle, may be transmitted via pasteurised milk. This is largely from work that has shown an unacceptable risk of survival of the organism when it is present in raw milk at numbers exceeding 102 cfu/ml. Three possible reasons for this apparent heat resistance were investigated viz. use of a milk heating menstruum, presence of a heat resistant sub–population, and the tendency of the organism to form clumps. Heat resistance studies using a combined acid–fast/viability stain, and a comparison of the relative heat sensitivities of clumped and de-clumped M. paratuberculosis cells provided circumstantial evidence that it is the organism's tendency to form clumps which confers the apparent heat resistance. This work casts doubt on the efficacy of current commercial pasteurisation heat treatments (72°C/15s) for the inactivation of M. paratuberculosis. This would be of concern if a link between M. paratuberculosis and Crohn's disease is eventually established.
Previous work has shown that amygdala responsiveness to fearful expressions is inversely related to level of callous-unemotional (CU) traits (i.e. reduced guilt and empathy) in youth with conduct problems. However, some research has suggested that the relationship between pathophysiology and CU traits may be different in those youth with significant prior trauma exposure.
In experiment 1, 72 youth with varying levels of disruptive behavior and trauma exposure performed a gender discrimination task while viewing morphed fear expressions (0, 50, 100, 150 fear) and Blood Oxygenation Level Dependent responses were recorded. In experiment 2, 66 of these youth performed the Social Goals Task, which measures self-reports of the importance of specific social goals to the participant in provoking social situations.
In experiment 1, a significant CU traits-by-trauma exposure interaction was observed within right amygdala; fear intensity-modulated amygdala responses negatively predicted CU traits for those youth with low levels of trauma but positively predicted CU traits for those with high levels of trauma. In experiment 2, a bootstrapped model revealed that the indirect effect of fear intensity amygdala response on social goal importance through CU traits is moderated by prior trauma exposure.
This study, while exploratory, indicates that the pathophysiology associated with CU traits differs in youth as a function of prior trauma exposure. These data suggest that prior trauma exposure should be considered when evaluating potential interventions for youth with high CU traits.
Deriving glacier outlines from satellite data has become increasingly popular in the past decade. In particular when glacier outlines are used as a base for change assessment, it is important to know how accurate they are. Calculating the accuracy correctly is challenging, as appropriate reference data (e.g. from higher-resolution sensors) are seldom available. Moreover, after the required manual correction of the raw outlines (e.g. for debris cover), such a comparison would only reveal the accuracy of the analyst rather than of the algorithm applied. Here we compare outlines for clean and debris-covered glaciers, as derived from single and multiple digitizing by different or the same analysts on very high- (1 m) and medium-resolution (30 m) remote-sensing data, against each other and to glacier outlines derived from automated classification of Landsat Thematic Mapper data. Results show a high variability in the interpretation of debris-covered glacier parts, largely independent of the spatial resolution (area differences were up to 30%), and an overall good agreement for clean ice with sufficient contrast to the surrounding terrain (differences ∼5%). The differences of the automatically derived outlines from a reference value are as small as the standard deviation of the manual digitizations from several analysts. Based on these results, we conclude that automated mapping of clean ice is preferable to manual digitization and recommend using the latter method only for required corrections of incorrectly mapped glacier parts (e.g. debris cover, shadow).
Antarctica Bedmap2 datasets are used to calculate subglacial hydraulic potential and the area, depth and volume of hydraulic potential sinks. There are over 32 000 contiguous sinks, which can be thought of as predicted lakes. Patterns of subglacial melt are modelled with a balanced ice flux flow model, and water fluxes are cumulated along predicted flow pathways to quantify steady-state fluxes from the main basin outlets and from known subglacial lakes. The total flux from the continent is ~21 km3 a−1. Byrd Glacier has the greatest basin flux of ~2.7 km3 a−1. Fluxes from subglacial lakes range from ~1 × 10−4 to ~1.5 km3 a−1. Lake turnover times are calculated from their volumes and fluxes, and have median values of ~100 a for known ‘active’ lakes and ~500 a for other lakes. Recurrence intervals of a 0.25 km3 flood range from ~2 months to ~2000 a (median ≈130 a) for known ‘active’ lakes and from ~2 to ~2400 a (median ≈ 360 a) for other lakes. Thus, several lakes that have recently been observed to fill and drain may not do so again for many centuries; and several lakes that have not, so far, been observed to fill and drain have the potential to do so, even at annual to decadal timescales.
Glaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland's second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass balance, we estimate the contribution of ice dynamics to elevation change. We use DEMs, in situ stake measurements, regional reanalyses and a mass-balance model to calculate the vertical ice velocity. Thus, we not only compare the geodetic, modelled and glaciological mass balances, but also map spatial variations in glacier dynamics. Maps of emergence and submergence velocity successfully highlight the 1998 surge and subsequent quiescence of one of Langjökull's outlets by visualizing both source and sink areas. In addition to observing the extent of traditional surge behaviour (i.e. mass transfer from the accumulation area to the ablation area followed by recharge of the source area), we see peripheral areas where the surge impinged upon an adjacent ridge and subsequently retreated. While mass balances are largely in good agreement, discrepancies between modelled and geodetic mass balance may be explained by inaccurate estimates of precipitation, saturated adiabatic lapse rate or degree-day factors. Nevertheless, the study was ultimately able to investigate dynamic surge behaviour in the absence of in situ measurements during the surge.
This article considers the hypothesis that the positive actions taken by members of Congress (MCs) influence citizens’ evaluations of them, their party, and Congress as an institution. We begin with a look at the available cross-sectional survey data on contact with legislators and legislator and institutional approval. Their legislative responsiveness appears to have a small spillover effect on institutions. However, when we employ a unique panel design that controls for prior levels of opinion and avoids recall bias, we find no evidence of spillover effects. Overall, we find that constituents who received a response from their own MC evaluate that representative more positively than those who did not receive a response, but legislator responsiveness does not predict evaluations of the MC’s political party or the Congress.
During the 2008 presidential campaign, the question of mass participation in primaries and caucuses became unusually salient, with a close Democratic race calling special attention to these often overlooked procedural elements of America's democratic system. This study adds a new element to scholarship on institutional design and citizen participation by way of a survey-based experiment conducted in the midst of the 2008 campaign. The results show that institutional choices are not neutral. Nominating candidates through caucuses rather than primaries not only reduces the number of participants, but also significantly affects the ideological composition of the electorate. Caucuses produce a more ideologically consistent electorate than do primaries, because policy centrists appear to avoid caucuses. This experimental finding is strongly buttressed by the observational data on Obama and Clinton voters.
Although several lichen inventories exist for European ultramafic sites, only four surveys of serpentine lichens for North America have been published to date. Of those, only one has been conducted in California. We conducted a survey of saxicolous lichens from ultramafic rocks (including nephrite, partially serpentinized peridotite, and serpentinite) and non-ultramafic rocks (including silica-carbonate, shale, and sandstone) at the New Idria serpentinite mass, San Benito County, California. X-ray Fluorescence Analysis of the rocks from which the lichens were collected revealed significant elemental differences between the ultramafic and non-ultramafic rocks for 26 of the 32 major and trace elements analyzed. We identified a total of 119 species of lichenized and lichenicolous fungi; 60 species were restricted to ultramafic substrata, 19 to silica-carbonate, and 15 to shale and sandstone. Only 4 species were shared in common. A permutational multivariate analysis of variance (perMANOVA) test revealed significant differences in lichen assemblages between ultramafic and non-ultramafic rocks at the species level but not at the generic level, with species richness (alpha-diversity) significantly greater at the ultramafic sites. We suggest that, although differences in geochemistry clearly influence the lichen community composition, other factors, especially substratum age and the physical characteristics of the rock, are of equal, if not greater, importance. Of all the species collected, six, Buellia aethalea, B. ocellata, Caloplaca oblongula, Rhizocarpon saurinum, Thelocarpon laureri, and Trapelia obtegens, are reported new to California, along with an apparently previously undescribed Solenopsora sp. The rest of the species encountered are relatively frequent in the lichen flora of southern and central California, except Aspicilia praecrenata, a rare California endemic that we collected on both ultramafic and non-ultramafic rocks.
Considerable efforts have been made to provide cow-calf producers with information to help them make informed decisions about adding value to calves. Despite demonstrated market incentives to retain calves, many producers still sell right after weaning. We postulate this observed behavior is related to producer risk aversion. Our study concludes risk aversion is an important factor affecting calf retention as the most risk-averse producers have more than a 60% probability of selling calves at weaning and the most risk tolerant have less than a 20% probability of selling at weaning.
Ectoparasitic copepods have been reported in a wide range of aquatic animals, including crustacean shellfish. However, with the exception of the salmon louse, Lepeophtheirus salmonis, our knowledge of such parasites in commercial species is rudimentary. The current study examines the morphology and pathology of the parasitic copepod, Nicothoë astaci (the ‘lobster louse’) in its host, the European lobster, Homarus gammarus. Lobsters were sampled from waters surrounding Lundy Island (Bristol Channel, UK) and all individuals collected were found to harbour female adult N. astaci in their gills, with a mean of 47·3 parasites/lobster. The majority of N. astaci were found in the basal region of pleurobranch gills. The parasite was found to attach to gill filaments via its oral sucker, maxillae and maxillipeds, and to feed on host haemolymph (blood) through a funnel-like feeding channel. It caused varying degrees of damage to the host gill, including occlusion of gill filaments and disruption to the vascular system in the central axis. Although there was evidence of extensive host response (haemocytic infiltration) to the parasite, it was displaced from the parasite attachment site and thus was observed in the central gill axis below. The region of gill filament immediately underlying the parasite feeding channel was devoid of such activity suggesting that the parasite interferes with the cellular defence and haemostatic mechanisms of the lobster in order to maintain invasion of the host.
By winning the presidency and strengthening its majority in both chambers of Congress, the 2008 election gave control of the government to the Democratic Party. However, as the 2010 election season unfolded, the news for the Democratic Party could not have been much worse. Economic conditions had not improved dramatically. A bitter and lengthy fight over health care reform signaled to citizens that little had changed in how Washington, DC, governed. The stimulus package and its impact on the federal debt caused unease in a segment of the electorate that was concerned with the size of government. In this context, observers of American politics began to take note of the number of citizens affiliating with, or at least expressing favorability toward, a loose coalition of groups known as the Tea Party movement. Tea Party rallies began to occur throughout the United States, seeking to draw attention to the movement's primary issues.
In the search for new thermoelectric materials, quasicrystals have been investigated due to their inherently low thermal conductivity. Crystalline phases called approximants which are closely related to the quasicrystals, however, have largely been ignored. These approximants have similar structure, yet the periodicity of a crystal. In this paper, we have investigated an icosahedral i-AlCuFe quasicrystalline phase as well as two of its corresponding approximant phases (ω and β). Electrical and thermal transport properties of these materials are presented. The viability of the i-AlCuFe quasicrystalline system and the ω and β approximant phases as thermoelectric materials is discussed.
Ordered intermetallics based on aluminides and silicides constitute a unique class of metallic materials possessing promising high-temperature properties. However, brittle fracture and poor ductility have limited their use as engineering materials in most cases. During the past ten years extensive research has been conducted on ordered intermetallics. As a result, significant progress has been made in identifying various causes of brittle fracture, and their relative importance in different ordered alloys. In some cases this understanding has helped achieve dramatic improvements in ductility. We review here three different classes of brittle fracture in ordered intermetallics and discuss the results in terms of model alloy systems chosen from each class. Ni3A1 and NiAl are discussed as prototypical ordered alloys prone to intrinsic intergranular brittleness. They are used to review our current understanding of intrinsically weak grain boundaries and the mechanisms by which boron is thought to suppress intergranular fracture. Next, FeAl and Fe3A1 are discussed as examples of ordered intermetallics that are susceptible to environmental embrittlement at ambient temperatures. Recent discoveries in these two alloy systems are reviewed with special emphasis on some of the rather interesting but subtle effects of test environment. Finally, A13X type intermetallics (A13 Sc, Al3Ti-base, and Al3 Zr-base alloys) are discussed as examples of ordered alloys that have high symmetry (L12 structure), are relatively soft, yet cleave transgranularly with very little ductility. In all these cases, experimental results are compared with theoretical calculations.
We have investigated the properties of surface alloys of Ti formed by excimer laser melting and mixing of Ti overlayers on AISI 304 stainless steel substrates.The thickness of the initial Ti surface layers and the fluence and number of pulses used to mix the surface were varied toinvestigate a broad range of processing conditions. Samples were uniformly translated at different speeds under repetitive pulses of homogenized laser radiation at 308 nm to vary the number of pulses incident on the sample. We investigated the surface structure and composition, the wear and friction behavior, and the surface hardness of the resulting alloys.
The extent of mixing is observed by Rutherford backscattering spectroscopy to be proportional to the number of pulses incident on the sample. Amorphous surface layers are formed at some mixing levels with a composition which indicates that Ti substitutes for Fe in the stainless steel on a one to one basis. Incorporation of C from surface and interface contamination is observed but at a level much below that found in comparable ion implanted materials.
Friction coefficient measurements indicate that there exists an optimum level of mixing for each layer thickness. Excessive mixing degrades both the coefficient of friction and the wear performance in dry sliding tests.
As with the tribological measurements, the surface hardness showed a dependence on amount of mixing. The surface hardness of the as deposited samples was higher than that of the laser mixed samples, initially decreased with mixing, and finally increased with further mixing.