Clues for consequentialists

In an influential paper, James Lenman argues that consequentialism can provide no basis for ethical guidance, because we are irredeemably ignorant of most of the consequences of our actions. If our ignorance of distant consequences is great, he says, we can have little reason to recommend one action over another on consequentialist grounds. In this article, I show that for reasons to do with statistical theory, the cluelessness objection is too pessimistic. We have good reason to believe that certain patterns of action will tend to have better consequences, and we have good reason to recommend acting in accordance with strategies based on those advantageous patterns. I close by saying something about the strategies that this argument should lead us to favour.</jats:p

New X-ray Selected Pre-Main Sequence Members of the Serpens Molecular Cloud

The study of young stars no longer surrounded by disks can greatly add to our understanding of how protoplanetary disks evolve and planets form. We have used VLT/FLAMES optical spectroscopy to confirm the youth and membership of 19 new young diskless stars in the Serpens Molecular Cloud, identified at X-ray wavelengths. Spectral types, effective temperatures and stellar luminosities were determined using the optical spectra and optical/near-IR photometry. Stellar masses and ages were derived based on PMS evolutionary tracks. The results yield remarkable similarities for age and mass distribution between the diskless and disk-bearing stellar populations in Serpens. We discuss the important impli- cations these similarities may have on the standard picture of disk evolution.Comment: Accepted for publication at the Astronomical Journal. 21 pages, 7 figures and 5 table

Interdisciplinary Dissertation Research Among Public Health Doctoral Trainees, 2003-2015

Given the call for more interdisciplinary research in public health, the objectives of this study were to (1) examine the correlates of interdisciplinary dissertation completion and (2) identify secondary fields most common among interdisciplinary public health graduates. METHODS: We analyzed pooled cross-sectional data from 11 120 doctoral graduates in the Survey of Earned Doctorates, 2003-2015. The primary outcome was interdisciplinary dissertation completion. Covariates included primary public health field, sociodemographic characteristics, and institutional attributes. RESULTS: From 2003 to 2015, a total of 4005 of 11 120 (36.0%) doctoral graduates in public health reported interdisciplinary dissertations, with significant increases observed in recent years. Compared with general public health graduates, graduates of environmental health (odds ratio [OR] = 1.74; P < .001) and health services administration (OR = 1.38; P < .001) doctoral programs were significantly more likely to report completing interdisciplinary dissertation work, whereas graduates from biostatistics (OR = 0.51; P < .001) and epidemiology (OR = 0.76; P < .001) were less likely to do so. Completing an interdisciplinary dissertation was associated with being male, a non-US citizen, a graduate of a private institution, and a graduate of an institution with high but not the highest level of research activity. Many secondary dissertation fields reported by interdisciplinary graduates included other public health fields. CONCLUSION: Although interdisciplinary dissertation research among doctoral graduates in public health has increased in recent years, such work is bounded in certain fields of public health and certain types of graduates and institutions. Academic administrators and other stakeholders may use these results to inform greater interdisciplinary activity during doctoral training and to evaluate current and future collaborations across departments or schools

Complex Patterns of Male Alliance Formation in a Dolphin Social Network

The formation and maintenance of alliances is regarded as one of the most socially complex male mating strategies in mammals. The prevalence and complexity of these cooperative relationships, however, varies considerably among species as well as within and between populations living in different ecological and social environments. We assessed patterns of alliance formation for Indo-Pacific bottlenose dolphins, Tursiops aduncus, in Port Stephens, New South Wales, Australia, to investigate the stability of these alliances, the structure of associations, as well as variation in schooling patterns among males. Our results showed that association patterns among males within this population showed considerable variability. Males either formed strong and enduring alliances that lasted for at least 8 years with minimal partner switching, or less stable partnerships within a much larger male social network. Male alliances with the strongest levels of association within a given time period were significantly more likely to maintain their relationships over the long term compared with alliances with lower levels of association. Males in stable alliances also associated in significantly smaller schools than males who formed less stable alliance partnerships. Finally, we found that alliances consisting of more related males did not persist longer than alliances between unrelated individuals. Our study suggests that intrapopulation variation in male alliance formation in dolphins likely reflects different mating strategies adopted as individual responses to their complex fission–fusion social environment

Drifting, moding, and nulling: another look at pulsar B1918+19

Arecibo observations of the conal triple pulsar B1918+19 at 0.327- and 1.4-GHz are used to analyse its subpulse behaviour in detail. We confirm the presence of three distinct drift modes (A,B,C) plus a disordered mode (N) and show that they follow one another in specific cycles. Interpreting the pulsar's profile as resulting from a sightline traverse which cuts across an outer cone and tangentially grazes an inner cone, we demonstrate that the phase modulation of the inner cone is locked to the amplitude modulation of the outer cone in all the drift modes. The 9% nulls are found to be largely confined to the dominant B and N modes, and, in the N mode, create alternating bunches of nulls and emission in a quasi-periodic manner with an averaged fluctuation rate of about 12 rotation periods ($P_1$). We explore the assumption that the apparent drift is the first alias of a faster drift of subbeams equally spaced around the cones. This is shown to imply that all modes A, B and C have a common circulation time of 12 $P_1$ and differ only in the number of subbeams. This timescale is on the same order as predicted by the classic {\bf E}$\times${\bf B} drift and also coincides with the N-mode modulation. We therefore arrive at a picture where the circulation speed remains roughly invariant while the subbeams progressively diminish in number from modes A to B to C, and are then re-established during the N mode. We suggest that aliasing combined with subbeam loss may be responsible for apparently dramatic changes in drift rates in other pulsars

Fundamental insights into ontogenetic growth from theory and fish

The fundamental features of growth may be universal, because growth trajectories of most animals are very similar, but a unified mechanistic theory of growth remains elusive. Still needed is a synthetic explanation for how and why growth rates vary as body size changes, both within individuals over their ontogeny and between populations and species over their evolution. Here we use Bertalanffy growth equations to characterize growth of ray-finned fishes in terms of two parameters, the growth rate coefficient, K, and final body mass, m∞. We derive two alternative empirically testable hypotheses and test them by analyzing data from FishBase. Across 576 species, which vary in size at maturity by almost nine orders of magnitude, K scaled as m_∞^(-0.23). This supports our first hypothesis that growth rate scales as m_∞^(-0.25) as predicted by metabolic scaling theory; it implies that species which grow to larger mature sizes grow faster as juveniles. Within fish species, however, K scaled as m_∞^(-0.35). This supports our second hypothesis which predicts that growth rate scales as m_∞^(-0.33) when all juveniles grow at the same rate. The unexpected disparity between across- and within-species scaling challenges existing theoretical interpretations. We suggest that the similar ontogenetic programs of closely related populations constrain growth to m_∞^(-0.33) scaling, but as species diverge over evolutionary time they evolve the near-optimal m_∞^(-0.25) scaling predicted by metabolic scaling theory. Our findings have important practical implications because fish supply essential protein in human diets, and sustainable yields from wild harvests and aquaculture depend on growth rates

CARMA CO(J = 2 - 1) Observations of the Circumstellar Envelope of Betelgeuse

We report radio interferometric observations of the 12C16O 1.3 mm J = 2-1 emission line in the circumstellar envelope of the M supergiant Alpha Ori and have detected and separated both the S1 and S2 flow components for the first time. Observations were made with the Combined Array for Research in Millimeter-wave Astronomy (CARMA) interferometer in the C, D, and E antenna configurations. We obtain good u-v coverage (5-280 klambda) by combining data from all three configurations allowing us to trace spatial scales as small as 0.9\arcsec over a 32\arcsec field of view. The high spectral and spatial resolution C configuration line profile shows that the inner S1 flow has slightly asymmetric outflow velocities ranging from -9.0 km s-1 to +10.6 km s-1 with respect to the stellar rest frame. We find little evidence for the outer S2 flow in this configuration because the majority of this emission has been spatially-filtered (resolved out) by the array. We also report a SOFIA-GREAT CO(J= 12-11) emission line profile which we associate with this inner higher excitation S1 flow. The outer S2 flow appears in the D and E configuration maps and its outflow velocity is found to be in good agreement with high resolution optical spectroscopy of K I obtained at the McDonald Observatory. We image both S1 and S2 in the multi-configuration maps and see a gradual change in the angular size of the emission in the high absolute velocity maps. We assign an outer radius of 4\arcsec to S1 and propose that S2 extends beyond CARMA's field of view (32\arcsec at 1.3 mm) out to a radius of 17\arcsec which is larger than recent single-dish observations have indicated. When azimuthally averaged, the intensity fall-off for both flows is found to be proportional to R^{-1}, where R is the projected radius, indicating optically thin winds with \rho \propto R^{-2}.Comment: 11 pages, 8 figures To be published in the Astronomical Journal (Received 2012 February 10; accepted 2012 May 25

Parental modelling, media equipment and screen-viewing among young children : cross-sectional study

Objective: To examine whether parental screenviewing, parental attitudes or access to media equipment were associated with the screen-viewing of 6-year-old to 8-year-old children. Design: Cross-sectional survey. Setting: Online survey. Main outcome: Parental report of the number of hours per weekday that they and, separately, their 6- year-old to 8-year-old child spent watching TV, using a games console, a smart-phone and multiscreen viewing. Parental screen-viewing, parental attitudes and pieces of media equipment were exposures. Results: Over 75% of the parents and 62% of the children spent more than 2 h/weekday watching TV. Over two-thirds of the parents and almost 40% of the children spent more than an hour per day multiscreen viewing. The mean number of pieces of media equipment in the home was 5.9 items, with 1.3 items in the child’s bedroom. Children who had parents who spent more than 2 h/day watching TV were over 7.8 times more likely to exceed the 2 h threshold. Girls and boys who had a parent who spent an hour or more multiscreen viewing were 34 times more likely to also spend more than an hour per day multiscreen viewing. Media equipment in the child’s bedroom was associated with higher TV viewing, computer time and multiscreen viewing. Each increment in the parental agreement that watching TV was relaxing for their child was associated with a 49% increase in the likelihood that the child spent more than 2 h/day watching TV. Conclusions: Children who have parents who engage in high levels of screen-viewing are more likely to engage in high levels of screen-viewing. Access to media equipment, particularly in the child’s bedroom, was associated with higher levels of screen-viewing. Family-based strategies to reduce screen-viewing and limit media equipment access may be important ways to reduce child screen-viewing