How virulent should a parasite be to its vector?

Journal ArticleVector-borne parasites are commonly predicted to be less virulent to the vector than to the definitive host as the parasite gains little by harming its main route of transmission. Here we assess the empirical evidence from systems in which insects are vectors for vertebrate, plant, and invertebrate parasites

Virulence management in biocontrol agents

Journal ArticleAlthough biological control is founded upon the virulence of natural enemies to the targeted pests, there has been little effort to understand how this might change, let alone to manage it. Frank Fenner and colleagues can be credited with being the first (and last!) to monitor changes in virulence of a biological control agent, namely the myxoma virus used to control rabbits in Australia (Fenner and Fantini 1999)

SB61-16/17: Resolution Regarding UM Foundation Strategic Funding Priorities

SB61-16/17: Resolution Regarding UM Foundation Strategic Funding Priorities. This resolution passed 24Y-0N-3A at the February 15, 2017 meeting of Associated Students of the University of Montana (ASUM)

Support services for victims and survivors of child sexual abuse

Some of the content in this report may be distressing to readers.Aims The four broad research aims were to: ● understand more about victims and survivors’ reasons for not accessing support services and any barriers to access; ● learn about victims and survivors’ perceptions and experiences of support services; ● understand what support services victims and survivors think are available to them and how to access them; and ● explore whether there are unmet needs for support services which impact on whether victims and survivors access support. Methods The sample was drawn from 634 adults who self-identified as victims and survivors of child sexual abuse as part of the ‘Abuse during childhood’ module in the Crime Survey for England and Wales (CSEW) year ending March 2019 (Office for National Statistics, 2020).3 A mixed-methods approach was used to explore the above research aims: ● A quantitative online survey4 of 181 victims and survivors from the CSEW recontact sample, including both those who had and had not accessed support. Descriptive and inferential analyses were conducted. ● Twenty-four qualitative in-depth interviews with three groups: (A) eight who had not accessed support services; (B) eight who self-identified as having had positive experiences of support services; and (C) eight who had negative experiences of support services. The interviews were analysed using thematic analysis. These were supplemented with six pen portraits (two from each of the above groups), and a network map to aid understanding of the service landscape. The research participants The ages of the survey respondents ranged from 19 to 74 years, with an average of 47 years. Around four in five identified as female (82%), the majority identified as being of a White ethnic background (92%), and one in three reported having a disability (33%). All regions of England and Wales were represented, with one in four living in London or South East England (26%). Nearly nine in ten identified as heterosexual (89%) Respondents reported experiencing between one and eight types of child sexual abuse. The two most common forms were being kissed or groped on any part of the body in a sexual way (73%) and penetration (64%). The age at first victimisation spanned from infancy to 17 years old, with an average of 9 years old. Child sexual abuse was more likely to have occurred in a familial setting (41%) than an institutional one (11%). Two in five (43%) respondents identified a friend, acquaintance or neighbour as the perpetrator. Around one in four (27%) identified an immediate – typically male – family member as the perpetrator. A stranger was identified by one in five (20%) respondents. Just over one in five respondents had never previously disclosed their experiences of child sexual abuse (21%), while four in five had made a disclosure (79%). Respondents were more than twice as likely to report making a disclosure later in life (75%) than at the time of the abuse (28%). A quarter disclosed at both points (24%)

The Responsive Cities Initiative: What a University Could Do To Help

In the fall of 2014, the Responsive Cities Initiative convened three workshops supported by a planning grant from the Ford Foundation and hosted by the Tow Center for Digital Journalism at Columbia Journalism School. The workshops gathered leading thinkers with the aim of answering the following question: What could a university center do to advance policymaking and planning for fiber-optic networks that provide everyone in the United States with high-speed Internet access and (a) improve local governance and (b) support civic journalism? We invited leading U.S. fiber builders, city officials, and civic journalists to the first two sessions and hosted a large group of Danish utility fiber companies and lawmakers at the third. This paper presents our findings

Corrigendum: Collective search by ants in microgravity

The problem of collective search is a tradeoff between searching thoroughly and covering as much area as possible. This tradeoff depends on the density of searchers. Solutions to the problem of collective search are currently of much interest in robotics and in the study of distributed algorithms, for example to design ways that without central control robots can use local information to perform search and rescue operations. Ant colonies operate without central control. Because they can perceive only local, mostly chemical and tactile cues, they must search collectively to find resources and to monitor the colony's environment. Examining how ants in diverse environments solve the problem of collective search can elucidate how evolution has led to diverse forms of collective behavior. An experiment on the International Space Station in January 2014 examined how ants (Tetramorium caespitum) perform collective search in microgravity. In the ISS experiment, the ants explored a small arena in which a barrier was lowered to increase the area and thus lower ant density. In microgravity, relative to ground controls, ants explored the area less thoroughly and took more convoluted paths. It appears that the difficulty of holding on to the surface interfered with the ants’ ability to search collectively. Ants frequently lost contact with the surface, but showed a remarkable ability to regain contact with the surface

Long Term Follow-Up of the Endovascular Trans-Vessel Wall Technique for Parenchymal Access in Rabbit with Full Clinical Integration

OBJECTIVE: Endovascular techniques are providing options to surgical/percutaneous cell transplantation methods. Some cells, e.g. insulin producing cells, are not suitable for intra-luminal transplantation and for such cells, other options must be found. We have constructed a "nanocatheter" with a penetrating tip for vessel perforation, thereby creating a working channel for parenchymal access by endovascular technique. To finish the procedure safely, the distal tip is detached to provide a securing plug in the vessel wall defect. MATERIALS AND METHODS: We have performed interventions with full clinical integration in the superior mesenteric artery (SMA), the subclavian artery and the external carotid artery in rabbits. No hemorrhagic- or thromboembolic events occurred during the procedure. Stenosis formation and distal embolisation were analyzed by angiography and macroscopic inspection during autopsy at five, 30 and 80 days. All animals and implanted devices were also evaluated by micro-dissections and histochemical analysis. RESULTS: In this study we show safety data on the trans-vessel wall technique by behavioral, angiographical and histological analysis. No stenosis formation was observed at any of the follow-up time points. No animals or organs have shown any signs of distress due to the intervention. Histological examination showed no signs of hemorrhage, excellent biocompatibility with no inflammation and a very limited fibrous capsule formation around the device, comparable to titanium implants. Further, no histological changes were detected in the endothelia of the vessels subject to intervention. CONCLUSIONS: The trans-vessel wall technique can be applied for e.g. cell transplantations, local substance administration and tissue sampling with low risk for complications during the procedure and low risk for hemorrhage, stenosis development or adverse tissue reactions with an 80 days follow-up time. The benefit should be greatest in organs that are difficult or risky to reach with surgical techniques, such as the pancreas, the CNS and the heart

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Reduction in Predator Defense in the Presence of Neighbors in a Colonial Fish

Predation pressure has long been considered a leading explanation of colonies, where close neighbors may reduce predation via dilution, alarming or group predator attacks. Attacking predators may be costly in terms of energy and survival, leading to the question of how neighbors contribute to predator deterrence in relationship to each other. Two hypotheses explaining the relative efforts made by neighbors are byproduct-mutualism, which occurs when breeders inadvertently attack predators by defending their nests, and reciprocity, which occurs when breeders deliberately exchange predator defense efforts with neighbors. Most studies investigating group nest defense have been performed with birds. However, colonial fish may constitute a more practical model system for an experimental approach because of the greater ability of researchers to manipulate their environment. We investigated in the colonial fish, Neolamprologus caudopunctatus, whether prospecting pairs preferred to breed near conspecifics or solitarily, and how breeders invested in anti-predator defense in relation to neighbors. In a simple choice test, prospecting pairs selected breeding sites close to neighbors versus a solitary site. Predators were then sequentially presented to the newly established test pairs, the previously established stimulus pairs or in between the two pairs. Test pairs attacked the predator eight times more frequently when they were presented on their non-neighbor side compared to between the two breeding sites, where stimulus pairs maintained high attack rates. Thus, by joining an established pair, test pairs were able to reduce their anti-predator efforts near neighbors, at no apparent cost to the stimulus pairs. These findings are unlikely to be explained by reciprocity or byproduct-mutualism. Our results instead suggest a commensal relationship in which new pairs exploit the high anti-predator efforts of established pairs, which invest similarly with or without neighbors. Further studies are needed to determine the scope of commensalism as an anti-predator strategy in colonial animals