Making causal claims

An ongoing challenge in evaluation is the need to make credible causal claims linking observed results to the actions of interventions. In the very common situation where the intervention is only one of a number of causal factors at play, the problem is compounded – no one factor 'caused' the result. The intervention on its own is neither necessary nor sufficient to bring about the result. The Brief argues the need for a different perspective on causality. One can still speak of the intervention making a difference in the sense that the intervention was a necessary element of a package of causal factors that together were sufficient to bring about the results. It was a contributory cause. The Brief further argues that theories of change are models showing how an intervention operates as a contributory cause. Using theories of change, approaches such as contribution analysis can be used to demonstrate that the intervention made a difference – that it was a contributory cause – and to explain how and why

Strengthening CPWF project evaluations: Assessing research-for-development impact

The Challenge Program on Water and Food (CPWF) funds research-for-development projects for 3-5 year periods with the aim of “increasing the productivity of water for food and livelihoods, in a manner that is environmentally sustainable and socially acceptable”. Impact evaluations of CPWF’s projects serve several purposes including lessons to improve implementation, lessons to inform uptake, and credible information to CPWF donors and other stakeholders. As part of CPWF’s adaptive management approach, this paper is intended to provide ideas and suggestions directed at both CPWF and its evaluators for improving the quality of future CPWF research-for- development project evaluations

Building an evaluative culture for effective evaluation and results management

A weak evaluative culture undermines many attempts at building an effective evaluation and results management regime. This brief outlines practical actions that an organization can take to build and support an evaluative culture, where information on performance is deliberately sought in order to learn how to better manage and deliver programmes and services. Such an organization values empirical evidence on the results it is seeking to achieve

Emerging incidence of Lyme borreliosis, babesiosis, bartonellosis, and granulocytic ehrlichiosis in Australia

Peter J MayneInternational Lyme and Associated Diseases Society, Bethesda, MD, USABackground: Borrelia burgdorferi, the causative agent of Lyme disease (LD), and Babesia, Bartonella, and Ehrlichia species (spp.) are recognized tick-borne pathogens in humans worldwide. Using serology and molecular testing, the incidence of these pathogens was investigated in symptomatic patients from Australia.Methods: Sera were analyzed by an immunofluorescent antibody assay (IFA) followed by immunoglobulin (Ig)G and IgM Western blot (WB) assays. Both whole blood and sera were analyzed for detection of specific Borrelia spp. DNA using multiplex polymerase chain reaction (PCR) testing. Simultaneously, patients were tested for Babesia microti, Babesia duncani, Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Bartonella henselae infection by IgG and IgM IFA serology, PCR, and fluorescent in situ hybridization (FISH).Results: Most patients reported symptom onset in Australia without recent overseas travel. 28 of 51 (55%) tested positive for LD. Of 41 patients tested for tick-borne coinfections, 13 (32%) were positive for Babesia spp. and nine (22%) were positive for Bartonella spp. Twenty-five patients were tested for Ehrlichia spp. and (16%) were positive for Anaplasma phagocytophilum while none were positive for Ehrlichia chaffeensis. Among the 51 patients tested for LD, 21 (41%) had evidence of more than one tick-borne infection. Positive tests for LD, Babesia duncani, Babesia microti, and Bartonella henselae were demonstrated in an individual who had never left the state of Queensland. Positive testing for these pathogens was found in three others whose movements were restricted to the east coast of Australia.Conclusion: The study identified a much larger tick-borne disease (TBD) burden within the Australian community than hitherto reported. In particular, the first cases of endemic human Babesia and Bartonella disease in Australia with coexisting Borrelia infection are described, thus defining current hidden and unrecognized components of TBD and demonstrating local acquisition in patients who have never been abroad.Keywords: Borrelia, lyme disease, Babesia, Bartonella, ehrlichiosis, Australia, human

Alien Registration- Mayne, William J. (Gardiner, Kennebec County)

https://digitalmaine.com/alien_docs/29187/thumbnail.jp

Songbird-mediated Insect Pest Control in Low Intensity New England Agriculture

Global agricultural intensification has caused large-scale wildlife declines, but agricultural lands that maintain natural habitats can support healthy wildlife populations and receive significant ecosystem services from these natural communities. However, how on-farm biodiversity results in beneficial ecosystem services is highly variable and is reported to differ among taxa and guilds. One group that has attracted attention for their potential beneficial role in reducing pest abundance are birds. Understanding the role of bird communities and individual species in pest control could be important for managing farms under a low intensity agroecological framework. In New England, farmers are increasingly applying low intensity agricultural practices, and these low intensity farms have high conservation value for bird communities. The value of bird communities to on-farm productivity, however, remains poorly understood. Therefore, we quantified the amount of insect pest control provided by birds to three important crops to New England farmers: brassicas (e.g., kale, broccoli), cucurbits (e.g., squash, cucumber), and Solanaceae (e.g., eggplant, potato). We also examined the role of different songbird species in the provision of pest control in this system. To determine the amount of pest control services provided by birds in this system, we conducted an exclusion experiment at nine low intensity farms in Franklin and Hampshire counties of Massachusetts. Birds were excluded from crops, and pest abundance and leaf damage were compared between exclusion plots and immediately adjacent control plots. In brassica crops, the abundance of imported cabbageworm (Pieris rapae) and diamondback moth (Plutella xylostella) were significantly reduced, while cabbage looper (Trichoplusia ni) was not significantly affected. In cucurbit crops, all life stages of squash bugs (Anasa tristis) were significantly reduced, though striped cucumber beetle (Acalymma vittatum) populations were not significantly changed. In Solanaceous crops, bird presence caused significantly larger populations of Colorado potato beetle (Leptinotarsa decemlineata) larvae, while the other life stages of Colorado potato beetle and aphids (superfamily Aphidoidea) were not significantly affected. Leaf damage was reduced by bird presence in all three crop types, though this effect was only significant for cucurbits. The varied effects of bird predation in different crop types highlights the need for crop-specific knowledge in applying agroecological pest management in New England. To determine the roles of different bird species in insect pest control, bird diets were studied at 11 low intensity farms in western Massachusetts. DNA metabarcoding was used to determine the frequency of crop pests and pest natural enemies in fecal samples collected from birds on each farm. We found evidence of pest species being consumed in 12.6% of the 737 total fecal samples collected, while pest natural enemies were present in 2.0% of samples. Among bird species, Gray Catbirds and Common Yellowthroats were determined to feed on crop pests significantly more frequently than Song Sparrows, while no bird species effect was found for natural enemy frequency. The only crop pest surveyed in our exclosure experiment which was present in fecal samples was Colorado potato beetle. Though birds preyed on Colorado potato beetle, they also preyed on two known predators of Colorado potato beetle eggs and larvae: Chrysopa oculata and Chrysoperla rufilabris. This provides evidence that the increase in Colorado potato beetle larvae we observed when birds were present was due to ecological release. Combined, our results show that birds provide important, though variable, insect pest control services on low intensity New England farms. Bird predation had primarily beneficial impacts on crops, suppressing abundance of several pest species and decreasing or minimally affecting leaf damage. The effects of bird predation on pest abundance and damage can be integrated into farm management to control insect pests without reliance on expensive, and sometimes damaging, outside inputs like pesticides. Promotion of woody, non-crop habitats on farms can promote species like Gray Catbirds and Common Yellowthroats that feed more frequently on insect pests. Management of New England farmlands for bird pest control may support healthy bird communities and improve agricultural output

Observational indicators of the transition from fully convective stars to stars with radiative cores

We present a discussion of the similarities and key differences between the transition onto (at the turn-on) and away from (at the turn-off) the main sequence, the latter termed the Hertzsprung gap. Using a set of model isochrones and adopting an initial mass function leads us to predict a dearth of G-type stars for any star forming region. This is caused by the (relatively) constant spectral type at which the transition from a fully convective star to a star with a radiative core begins. We also present analysis of the details of this transition in the ONC. In particular we show that a gap in the photometric and spectral type distributions is centred on, and a change in the fractional X-ray luminosity and rotation rate distribution occurs approximately at, the position of a peak in radiative core size as a function of mass. Whilst photometric signatures of this transition are lost at ages over ~20 Myrs, we show that changes in fractional X-ray luminosity and magnetic field configuration persist to older ages. Analysis of literature data show that the mass at which the change in fractional X-ray luminosity is observed decreases with age.Comment: 9 pages and 6 figures. Accepted for publication in MNRA

When the path is never shortest: a reality check on shortest path biocomputation

Shortest path problems are a touchstone for evaluating the computing performance and functional range of novel computing substrates. Much has been published in recent years regarding the use of biocomputers to solve minimal path problems such as route optimisation and labyrinth navigation, but their outputs are typically difficult to reproduce and somewhat abstract in nature, suggesting that both experimental design and analysis in the field require standardising. This chapter details laboratory experimental data which probe the path finding process in two single-celled protistic model organisms, Physarum polycephalum and Paramecium caudatum, comprising a shortest path problem and labyrinth navigation, respectively. The results presented illustrate several of the key difficulties that are encountered in categorising biological behaviours in the language of computing, including biological variability, non-halting operations and adverse reactions to experimental stimuli. It is concluded that neither organism examined are able to efficiently or reproducibly solve shortest path problems in the specific experimental conditions that were tested. Data presented are contextualised with biological theory and design principles for maximising the usefulness of experimental biocomputer prototypes.Comment: To appear in: Adamatzky, A (Ed.) Shortest path solvers. From software to wetware. Springer, 201