Arecibo HI Absorption Measurements of Pulsars and the Electron Density at Intermediate Longitudes in the First Galactic Quadrant

We have used the Arecibo telescope to measure the HI absorption spectra of eight pulsars. We show how kinematic distance measurements depend upon the values of the galactic constants R_o and Theta_o, and we select our preferred current values from the literature. We then derive kinematic distances for the low-latitude pulsars in our sample and electron densities along their lines of sight. We combine these measurements with all others in the inner galactic plane visible from Arecibo to study the electron density in this region. The electron density in the interarm range 48 degrees < l < 70 degrees is [0.017 (-0.007,+0.012) (68% c.l.)] cm^(-3). This is 0.75 (-0.22,+0.49) (68% c.l.) of the value calculated by the Cordes & Lazio (2002) galactic electron density model. The model agrees more closely with electron density measurements toward Arecibo pulsars lying closer to the galactic center, at 30 degrees<l<48 degrees. Our analysis leads to the best current estimate of the distance of the relativistic binary pulsar B1913+16: d=(9.0 +/- 3) kpc. We use the high-latitude pulsars to search for small-scale structure in the interstellar hydrogen observed in absorption over multiple epochs. PSR B0301+19 exhibited significant changes in its absorption spectrum over 22 yr, indicating HI structure on a ~500 AU scale.Comment: Accepted by Astrophysical Journal September 200

Partisan Defection and Change in the 2008 US Presidential Election

Party identification remained an important determinant of vote choice in the 2008 election. Indeed, the extent to which people voted according to their partisanship remained as exceptionally high as it had been in the 2004 election. The Democrats led in partisanship, with a greater lead than in 2004. The ANES four‐wave panel survey shows that some change occurred in the Democratic direction during 2008. The Democrats gained among most population groups, with the exception of older citizens. Obama\u27s victory margin was due to his carrying pure independents and the growth in strong Democrats as opposed to strong Republicans. Both candidates lost the votes of some partisans who disagreed with them ideologically. The rate of defection among major‐party identifiers to the other major party hit post‐1950 lows in 2004 and 2008, reflecting increased polarization in the electorate. The partisanship shifts of young people and Hispanics could portend realignment, although that depends on their satisfaction with the Obama administration

Racial Attitude Effects in the 2008 Presidential Election: Examining the Unconventional Factors Shaping Vote Choice in a Most Unconventional Election

Every election has unique elements, but the 2008 U.S. presidential race had it all: an African-American presidential candidate who won his party’s nomination by defeating a former first lady, an historically unpopular outgoing president, two ongoing wars, a failing economy, and a war hero running for president with a female vice-presidential running mate. With so many unique elements to account for, disentangling their independent effects to identify the dominant factors shaping the 2008 election is a tremendous challenge. This paper explores a wide variety of factors potentially influencing the 2008 vote, but it devotes particular attention to two exceptionally relevant factors: racial attitudes and succession effects. We begin this paper with a discussion of racial attitudes and succession effects’ relevance to vote choice. Then we test the effects of racial attitudes and succession effects, as well as other important factors, on vote choice in 2008, by analyzing the 2008 American National Election Studies (ANES) traditional September–October pre-election survey and November–December post-election survey.1 Finally, we test whether the racial attitude effects found in our 2008 results are unique to the Obama candidacy, or if similar results would be obtained by comparable analysis of the two most recent elections not contested by an incumbent president, the elections of 1988 and 2000, or in the preceding election of 2004. Stated concisely, our analysis shows that, of all the unusual factors shaping vote choice in 2008, two particularly important ones were racial attitudes and dissatisfaction with the Bush Administration. The comparison with 1988 and 2000 shows that attitudes toward the previous administration generally affect voting even when the incumbent is not running, and regardless of whether the incumbent party’s presidential candidate was a member of the outgoing presidential administration. The comparison with previous elections, including 2004, also provides an important demonstration that the racial attitudes effect was specific to 2008. Clearly, the historic nomination of an African-American for the presidency made racial attitudes more important in voting than they had been in analogous elections

"Antiscepticism and Easy Justification" - Ch 5 of Seemings and Epistemic Justification

In this chapter I investigate epistemological consequences of the fact that seeming-based justification is elusive, in the sense that the subject can lose this justification simply by reflecting on her seemings. I argue that since seeming-based justification is elusive, the antisceptical bite of phenomenal conservatism is importantly limited. I also contend that since seeming-based justification has this feature, phenomenal conservatism isn’t actually afflicted by easy justification problems

Incidence and public health burden of sunburn among beachgoers in the United States.

The beach environment creates many barriers to effective sun protection, putting beachgoers at risk for sunburn, a well-established risk factor for skin cancer. Our objective was to estimate incidence of sunburn among beachgoers and evaluate the relationship between sunburn incidence and sun-protective behaviors. A secondary analysis, of prospective cohorts at 12 locations within the U.S. from 2003 to 2009 (n&nbsp;=&nbsp;75,614), were pooled to evaluate sunburn incidence 10-12&nbsp;days after the beach visit. Behavioral and environmental conditions were cross-tabulated with sunburn incidence. Multivariable logistic regression was used to estimate the association between new sunburn and sun-protective behaviors. Overall, 13.1% of beachgoers reported sunburn. Those aged 13-18&nbsp;years (16.5%), whites (16.0%), and those at beach locations along the Eastern Seaboard (16.1%), had the highest incidence of sunburn. For those spending ≥5&nbsp;h in the sun, the use of multiple types of sun protection reduced odds of sunburn by 55% relative to those who used no sun protection (Odds Ratio&nbsp;=&nbsp;0.45 (95% Confidence Interval:0.27-0.77)) after adjusting for skin type, age, and race. Acute health effects of sunburn tend to be mild and self-limiting, but potential long-term health consequences are more serious and costly. Efforts to encourage and support proper sun-protective behaviors, and increase access to shade, protective clothing, and sunscreen, can help prevent sunburn and reduce skin cancer risk among beachgoers

Upper and lower treeline biogeographic patterns in semi-arid pinyon-juniper woodlands

none7siAim: Upper and lower treelines are particularly exposed to a changing climate. It has been hypothesized that upper treelines are constrained by growing season temperature, whereas lower tree lines are water limited. We expect different causal mechanisms of upper versus lower tree line formation to generate distinct patterns of spatial heterogeneity. Here, we compare dynamics, spatial patterns and shape complexity of upper and lower tree lines of semi‐arid pinyon‐juniper woodlands. Location: Toiyabe Range of the Nevada Great Basin (western US). Taxon: Pinus monophylla Torr. & Frém. and Juniperus osteosperma (Torr.). Methods: Within 20 sample plots (10 along the upper and 10 along the lower tree line), we mapped tree canopies through photointerpretation of high‐resolution imagery. We performed point pattern analyses to compare the spatial arrangement of trees and used LANDSAT 30‐year time series and NDVI to understand the vegetation dynamics of these ecotones. We adopted the surface roughness method to measure tree line shape complexity. Results: Lower tree lines were denser and showed a stronger trend of increasing NDVI change over the 1984–2015 period. Trees at the lower tree line were more strongly aggregated than at the upper tree line at spatial scales ranging from 15 to 65 meters. Shape complexity was higher at upper tree lines, expressed by a higher mean surface roughness; however, the spatial structures of upper and lower tree lines were similar. Main conclusions: Upper tree line expansion of pinyon‐juniper woodlands in the study area has been limited and highly variable, but lower tree line downslope expansion into adjacent shrub steppe vegetation was evident. The expected difference between energy‐ and water‐limited tree lines did not manifest in the observed spatial structures. Differences in tree line shape complexity were not significant, although lower tree lines exhibited less complex shapes, likely because they have been more strongly influenced by anthropogenic factors.The datasets generated and analysed during the current study are available in the Figshare repository, https://doi.org/10.6084/m9.figshare.11836284mixedGarbarino, Matteo; Malandra, Francesco; Dilts, Thomas; Flake, Sam; Montalto, Luigi; Spinsante, Susanna; Weisberg, Peter J.Garbarino, Matteo; Malandra, Francesco; Dilts, Thomas; Flake, Sam; Montalto, Luigi; Spinsante, Susanna; Weisberg, Peter J

The Relationship Between Belief and Credence

Sometimes epistemologists theorize about belief, a tripartite attitude on which one can believe, withhold belief, or disbelieve a proposition. In other cases, epistemologists theorize about credence, a fine-grained attitude that represents one’s subjective probability or confidence level toward a proposition. How do these two attitudes relate to each other? This article explores the relationship between belief and credence in two categories: descriptive and normative. It then explains the broader significance of the belief-credence connection and concludes with general lessons from the debate thus far

The Strange Prospects for Astrophysics

The implications of the formation of strange quark matter in neutron stars and in core-collapse supernovae is discussed with special emphasis on the possibility of having a strong first order QCD phase transition at high baryon densities. If strange quark matter is formed in core-collapse supernovae shortly after the bounce, it causes the launch of a second outgoing shock which is energetic enough to lead to a explosion. A signal for the formation of strange quark matter can be read off from the neutrino spectrum, as a second peak in antineutrinos is released when the second shock runs over the neutrinosphere.Comment: 10 pages, 8 figures, invited talk given at the international conference on strangeness in quark matter (SQM2008), Beijing, October 6-10, Beijing, China, version to appear in J. Phys.

Apparent Faster-Than-Light Pulse Propagation in Interstellar Space: A new probe of the Interstellar Medium

Radio pulsars emit regular bursts of radio radiation that propagate through the interstellar medium (ISM), the tenuous gas and plasma between the stars. Previously known dispersive properties of the ISM cause low frequency pulses to be delayed in time with respect to high frequency ones. This effect can be explained by the presence of free electrons in the medium. The ISM also contains neutral hydrogen which has a well known resonance at 1420.4 MHz. Electro-magnetic theory predicts that at such a resonance, the induced dispersive effects will be drastically different from those of the free electrons. Pulses traveling through a cloud of neutral hydrogen should undergo "anomalous dispersion", which causes the group velocity of the medium to be larger than the speed of light in vacuum. This superluminal group velocity causes pulses containing frequencies near the resonance to arrive earlier in time with respect to other pulses. Hence, these pulses appear to travel faster than light. This phenomenon is caused by an interplay between the time scales present in the pulse and the time scales present in the medium. Although counter-intuitive, it does not violate the laws of special relativity. Here, we present Arecibo observations of the radio pulsar PSR B1937+21 that show clear evidence of anomalous dispersion. Though this effect is known in laboratory physics, this is the first time it has been directly observed in an astrophysical context, and it has the potential to be a useful tool for studying the properties of neutral hydrogen in the Galaxy.Comment: Accepted by Astrophysical Journal. (Latest version fixed references.

Male Competition Reverses Female Preference For Male Chemical Cues

Females must choose among potential mates with different phenotypes in a variety of social contexts. Many male traits are inherent and unchanging, but others are labile to social context. Competition, for example, can cause physiological changes that reflect recent wins and losses that fluctuate throughout time. We may expect females to respond differently to males depending on the outcome of their most recent fight. In Bolitotherus cornutus (forked fungus beetles), males compete for access to females, but copulation requires female cooperation. In this study, we use behavioral trials to determine whether females use chemical cues to differentiate between males and whether the outcome of recent male competition alters female preference. We measured female association time with chemical cues of two size‐matched males both before and after male–male competition. Females in our study preferred to associate with future losers before males interacted, but changed their preference for realized winners following male competitive interactions. Our study provides the first evidence of change in female preference based solely on the outcome of male–male competition