Gravitational Microlensing by Globular Clusters

Stars in globular clusters can act either as sources for MACHOs (Massive Astrophysical Compact Halo Objects) located along the line of sight or as lenses for more distant background stars. Although the expected rate of microlensing events is small, such observations can lead to very useful results. In particular, one could get information on the shape of the galactic halo along different lines of sight, allowing to better constrain its total dark matter content. Moreover, on can also infer the total dark matter content of globular clusters, which is presently not well known. To this latter purpose, we analyse the microlensing events towards the galactic bulge, which lie close to the three globular clusters NGC 6522, NGC 6528 and NGC 6540. We find evidence that some microlensing events are indeed due to MACHOs located in the globular clusters, suggesting, therefore, that these clusters contain a significant amount of dark matter.Comment: 15 pages, 10 figures included. Accepted for publication in A &

Development of microsatellite loci in the European Dipper, Cinclus cinclus

Eighteen polymorphic microsatellite DNA loci were isolated in the Central European subspecies of the European Dipper (Cinclus cinclus aquaticus). The loci were tested for polymorphism using a test panel of 24 breeding birds. Numbers of alleles ranged from 2 to 21 per locus and expected heterozygosities varied between 0.47 and 0.83. Two loci (Cici10 and Cici12) proved to be Z-linked. Some pairs of loci exhibited significant linkage disequilibrium but not the two loci that are located on the Z-chromosome. This pattern suggests that demographic effects rather than physical linkage are likely responsible for the observed levels of linkage disequilibrium. These loci will be useful for applied conservation projects and for investigations of the dispersal and mating patterns of European and other dipper

Bigger is fitter? Quantitative genetic decomposition of selection reveals an adaptive evolutionary decline of body mass in a wild rodent population

This is the final version of the article. Available from the publisher via the DOI in this record.In natural populations, quantitative trait dynamics often do not appear to follow evolutionary predictions. Despite abundant examples of natural selection acting on heritable traits, conclusive evidence for contemporary adaptive evolution remains rare for wild vertebrate populations, and phenotypic stasis seems to be the norm. This so-called "stasis paradox" highlights our inability to predict evolutionary change, which is especially concerning within the context of rapid anthropogenic environmental change. While the causes underlying the stasis paradox are hotly debated, comprehensive attempts aiming at a resolution are lacking. Here, we apply a quantitative genetic framework to individual-based long-term data for a wild rodent population and show that despite a positive association between body mass and fitness, there has been a genetic change towards lower body mass. The latter represents an adaptive response to viability selection favouring juveniles growing up to become relatively small adults, i.e., with a low potential adult mass, which presumably complete their development earlier. This selection is particularly strong towards the end of the snow-free season, and it has intensified in recent years, coinciding which a change in snowfall patterns. Importantly, neither the negative evolutionary change, nor the selective pressures that drive it, are apparent on the phenotypic level, where they are masked by phenotypic plasticity and a non causal (i.e., non genetic) positive association between body mass and fitness, respectively. Estimating selection at the genetic level enabled us to uncover adaptive evolution in action and to identify the corresponding phenotypic selective pressure. We thereby demonstrate that natural populations can show a rapid and adaptive evolutionary response to a novel selective pressure, and that explicitly (quantitative) genetic models are able to provide us with an understanding of the causes and consequences of selection that is superior to purely phenotypic estimates of selection and evolutionary change.The study was funded by a Swiss National Science Foundation (http://www.snf.ch) project grant (31003A_141110) awarded to EP

Microsatellite primers for the four Galápagos mockingbird species (Mimus parvulus, Mimus macdonaldi, Mimus melanotis and Mimus trifasciatus)

Nineteen di- and tetranucleotide and one trinucleotide microsatellite DNA markers were isolated from the Galapagos mockingbird (Mimus parvulus) and tested for cross-species amplification in the other three mockingbird species in the Galapagos. In addition, primers for two microsatellite loci previously developed for Mimus polyglottos were redesigned to obtain shorter amplification fragments. The number of alleles per locus and species ranged from 1 to 8, and expected heterozygosity varied from 0.0 to 0.809. These microsatellite markers will be useful to study levels of inbreeding in different island populations

Rabies elimination research: juxtaposing optimism, pragmatism and realism

More than 100 years of research has now been conducted into the prevention, control and elimination of rabies with safe and highly efficacious vaccines developed for use in human and animal populations. Domestic dogs are a major reservoir for rabies, and although considerable advances have been made towards the elimination and control of canine rabies in many parts of the world, the disease continues to kill tens of thousands of people every year in Africa and Asia. Policy efforts are now being directed towards a global target of zero human deaths from dog-mediated rabies by 2030 and the global elimination of canine rabies. Here we demonstrate how research provides a cause for optimism as to the feasibility of these goals through strategies based around mass dog vaccination. We summarize some of the pragmatic insights generated from rabies epidemiology and dog ecology research that can improve the design of dog vaccination strategies in low- and middle-income countries and which should encourage implementation without further delay. We also highlight the need for realism in reaching the feasible, although technically more difficult and longer-term goal of global elimination of canine rabies. Finally, we discuss how research on rabies has broader relevance to the control and elimination of a suite of diseases of current concern to human and animal health, providing an exemplar of the value of a ‘One Health’ approach

Monitoring introgression in European wildcats in the Swiss Jura

Introgression is an important evolutionary force, which can lead to adaptation and speciation on one hand, but on the other hand also to genetic extinction. It is in the latter sense that introgression is a major conservation concern, especially when domestic species reproduce with their rare wild relatives. Hence, monitoring introgression in natural populations subject to hybridization is crucial to elucidate the threat represented by introgression. Here, we monitored introgression between wildcats (Felis silvestris silvestris) and domestic cats (Felis silvestris catus) in a wildcat population in the Swiss Jura Mountains using systematically and non-invasively collected hair samples. We found 21% admixed individuals based on 68 diagnostic nuclear SNP-markers, corresponding to a migration rate from domestic cats to wildcats of 0.02 migrants per generation. In contrast, gene flow from wildcats into domestic cats was negligible. Haphazard sampling of the same wildcat population, mostly via road kills, led to similar results. Hybridization occurred between wildcat male and domestic cat female and vice versa and, based on the occurrence of backcrosses, both female and male F1-hybrids seem viable and fertile. The observed hybridization pattern may indicate an expanding wildcat population with introgression as a byproduct of this expansion but alternative explanations cannot be excluded with the current data

The Presence of Human Immunodeficiency Virus-Associated Neurocognitive Disorders Is Associated With a Lower Adherence to Combined Antiretroviral Treatment.

Human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) are defined according to their diagnostic degrees as follows: asymptomatic neurocognitive impairment, mild neurocognitive disorder, and HIV-associated dementia. Because high adherence to combined antiretroviral therapy (cART) is required to maintain viral suppression among HIV-infected patients, it is important to investigate the impact of HAND on medication adherence. Our study hypothesis was that patients with HAND had a lower medication adherence than patients who did not have HAND. This was an observational, exploratory, 2-center pilot study of patients who had a state-of-the-art neurocognitive assessment performed between January 2011 and June 2015 while also being followed at their respective adherence clinics. Adherence was measured with electronic monitors. Patients' sociodemographic characteristics, HIV viral load, and CD4 counts were retrieved from the Swiss HIV Cohort Study database. At each time t, adherence was computed as the proportion of patients taking medication as prescribed at that time. We included 59 patients, with a median (Q1, Q3) age of 53 years (47-58) and 39 (66%) were male participants. Twenty-two patients (35%) had no neurocognitive deficits, 16 (27%) patients had HAND, and 21 (35%) patients had non-HAND (mostly depression). Implementation over 3 years showed a significant decline (50%) in medication adherence among patients diagnosed with HAND in comparison with patients who had a normal neuropsychological status or a non-HIV-related cognitive deficit (implementation stayed 90% during follow-up). Our findings support the hypothesis that HAND is associated with reduced cART adherence

Elimination of Arctic Variant Rabies in Red Foxes, Metropolitan Toronto

To control the arctic variant of rabies virus in red foxes, 332,257 bait doses containing live, attenuated Evelyn-Rokitnicki-Abelseth rabies vaccine were distributed in greater metropolitan Toronto during 1989–1999. Human and pet contact with bait was minimal, and no adverse reactions to the vaccine were noted. Significantly fewer rabid foxes were found during the 17 years after fox baiting (5 cases during 1990–2006) than in the 17 years before (96 cases during 1973–1989). The last report of a rabid fox in metropolitan Toronto was in 1996 (reporting period through September 2006), which confirms that distributing oral rabies vaccine bait is a feasible tactic for the control of rabies in foxes in urban environments

Clusters of Sexual Behavior in Human Immunodeficiency Virus-positive Men Who Have Sex With Men Reveal Highly Dissimilar Time Trends.

Separately addressing specific groups of people who share patterns of behavioral change might increase the impact of behavioral interventions to prevent transmission of sexually transmitted infections. We propose a method based on machine learning to assist the identification of such groups among men who have sex with men (MSM). By means of unsupervised learning, we inferred "behavioral clusters" based on the recognition of similarities and differences in longitudinal patterns of condomless anal intercourse with nonsteady partners (nsCAI) in the HIV Cohort Study over the last 18 years. We then used supervised learning to investigate whether sociodemographic variables could predict cluster membership. We identified 4 behavioral clusters. The largest behavioral cluster (cluster 1) contained 53% of the study population and displayed the most stable behavior. Cluster 3 (17% of the study population) displayed consistently increasing nsCAI. Sociodemographic variables were predictive for both of these clusters. The other 2 clusters displayed more drastic changes: nsCAI frequency in cluster 2 (20% of the study population) was initially similar to that in cluster 3 but accelerated in 2010. Cluster 4 (10% of the study population) had significantly lower estimates of nsCAI than all other clusters until 2017, when it increased drastically, reaching 85% by the end of the study period. We identified highly dissimilar behavioral patterns across behavioral clusters, including drastic, atypical changes. The patterns suggest that the overall increase in the frequency of nsCAI is largely attributable to 2 clusters, accounting for a third of the population

Emergence of Arctic-like Rabies Lineage in India

Progenitors of Arctic-like rabies viruses, which now circulate extensively in India, may have been responsible for the emergence of the Arctic rabies lineage