A Major Transition in Immune System Evolution

Social insect colonies can express adaptive, organism-like design. In some cases, colonies so resemble a unique, cohesive and integrated “individual” that they are termed superorganisms. The major evolutionary transitions framework explains, via inclusive fitness theory, how new levels of biological individuality, including genes into genomes within cells, cells into multicellular organisms and organisms into superorganisms can emerge. Importantly, it highlights how at each major transition similar challenges arose and why seemingly convergent solutions evolved. One challenge faced at each transition is exploitation, caused internally by social cheaters and externally by parasites and pathogens. To overcome the problem of exploitation transitions in biological individuality required novel immune systems to maintain the integrity of newly emerged individuals. Multicellular organisms evolved an immune system while social insect colonies evolved a social immune system. In this review, we take a major transitions perspective of immunity to highlight the interdependency between the evolution of immune systems and the emergence of biological individuality. We build on the notion that superorganisms have evolved an immune system to promote the fitness of the colony. We draw parallels between the evolution of the metazoan immune system and the social immune system, and their expression as cognitive networks. Moreover, we discuss how research on other group-living species, such as family based cooperative breeders, can inform our understanding of how social immune systems evolve. We conclude that superorganism immunity is an adaptive suite of organismal traits that evolves to maximize the fitness of advanced social insect colonies, fulfilling the same function as the immune system of Metazoa

So near and yet so far: Harmonic radar reveals reduced homing ability of nosema infected honeybees

Pathogens may gain a fitness advantage through manipulation of the behaviour of their hosts. Likewise, host behavioural changes can be a defence mechanism, counteracting the impact of pathogens on host fitness. We apply harmonic radar technology to characterize the impact of an emerging pathogen - Nosema ceranae (Microsporidia) - on honeybee (Apis mellifera) flight and orientation performance in the field. Honeybees are the most important commercial pollinators. Emerging diseases have been proposed to play a prominent role in colony decline, partly through sub-lethal behavioural manipulation of their hosts. We found that homing success was significantly reduced in diseased (65.8%) versus healthy foragers (92.5%). Although lost bees had significantly reduced continuous flight times and prolonged resting times, other flight characteristics and navigational abilities showed no significant difference between infected and non-infected bees. Our results suggest that infected bees express normal flight characteristics but are constrained in their homing ability, potentially compromising the colony by reducing its resource inputs, but also counteracting the intra-colony spread of infection. We provide the first high-resolution analysis of sub-lethal effects of an emerging disease on insect flight behaviour. The potential causes and the implications for both host and parasite are discussed

Barriers to integrating direct oral anticoagulants into anticoagulation clinic care: A mixedâ methods study

BackgroundOutpatient anticoagulation clinics were initially developed to care for patients taking vitamin K antagonists such as warfarin. There has not been a systematic evaluation of the barriers and facilitators to integrating direct oral anticoagulant (DOAC) care into outpatient anticoagulation clinics.MethodsWe performed a mixed methods study consisting of an online survey of anticoagulation clinic providers and semiâ structured interviews with anticoagulation clinic leaders and managers between March and May of 2017. Interviews were transcribed and coded, exploring for themes around barriers and facilitators to DOAC care within anticoagulation clinics. Survey questions pertaining to the specific themes identified in the interviews were analyzed using summary statistics.ResultsSurvey responses were collected from 159 unique anticoagulation clinics and 20 semiâ structured interviews were conducted. Three primary barriers to DOAC care in the anticoagulation clinic were described by the interviewees: (a) a lack of provider awareness for ongoing monitoring and services provided by the anticoagulation clinic; (b) financial challenges to providing care to DOAC patients in an anticoagulation clinic model; and (c) clinical knowledge versus scope of care by the anticoagulation staff. These themes linked to three key areas of variation, including: (a) the size and hospital affiliation of the anticoagulation clinic; (b) the use of faceâ toâ face versus telephoneâ based care; and (c) the use of nurses or pharmacists in the anticoagulation clinic.ConclusionsAnticoagulation clinics in the United States experience important barriers to integrating DOAC care. These barriers vary based on the clinic size, model for warfarin care, and staff credentials (nursing or pharmacy).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147845/1/rth212157.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147845/2/rth212157_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147845/3/rth212157-sup-0001-Supinfo.pd

How to detect gravitational waves through the cross-correlation of the galaxy distribution with the CMB polarization

Thompson scattering of cosmic microwave background (CMB) photons off of free electrons during the reionization epoch induces a correlation between the distribution of galaxies and the polarization pattern of the CMB, the magnitude of which is proportional to the quadrupole moment of radiation at the time of scattering. Since the quadrupole moment generated by gravitational waves (GWs) gives rise to a different polarization pattern than that produced by scalar modes, one can put interesting constraints on the strength of GWs on large scales by cross-correlating the small scale galaxy distribution and CMB polarization. We use this method together with Fisher analysis to predict how well future surveys can measure the tensor-to-scalar ratio $r$. We find that with a future CMB experiment with detector noise Delta_P = 2 mu K-arcmin and a beam width theta_FWHM = 2' and a future galaxy survey with limiting magnitude I<25.6 one can measure the tensor-to-scalar ratio with an error sigma_r \simeq 0.09. To measure r \approx 0.01, however, one needs Delta_P \simeq 0.5 mu K-radian and theta_FWHM \simeq 1'. We also investigate a few systematic effects, none of which turn out to add any biases to our estimators, but they increase the error bars by adding to the cosmic variance. The incomplete sky coverage has the most dramatic effect on our constraints on r for large sky cuts, with a reduction in signal-to-noise smaller than one would expect from the naive estimate (S/N)^2 \propto f_sky. Specifically, we find a degradation factor of f_deg=0.32 \pm 0.01 for a sky cut of |b|>10^\circ (f_sky=0.83) and f_deg=0.056 \pm 0.004 for a sky cut of |b|>20^\circ (f_sky=0.66). Nonetheless, given that our method has different systematics than the more conventional method of observing the large scale B modes directly, it may be used as an important check in the case of a detection.Comment: 18 pages, 6 figures, to be submitted to PR

Simulations of the OzDES AGN reverberation mapping project

As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ≥500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius-luminosity (R-L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for-35-45 per cent of the quasars. AGN with shorter lags and greater variability aremore likely to yield a lag measurement, and objects with lags ≲6 months or-1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R-L relationship parameters for H β, MgII λ2798, and CIV λ1549. Extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R-L parameter constraints for all broad emission lines