Using Artificial Selection to Understand Orientation Behavior in Drosophila

Several studies suggest that the fruit fly Drosophila melanogaster can use magnetic fields for orientation1-4; however, the responses to magnetic fields are not consistent across studies and experiments investigating the mechanism of magnetoreception rely on magnetic fields that are at least 10 times stronger than the magnetic field of the Earth5-6. We are attempting to determine whether Drosophila have the ability to detect Earth-strength magnetic fields by running flies through a progressive Y-maze and then selectively breeding the flies based on their choices in the maze. There are two main hypotheses about the mechanism of magnetoreception in animals. The first is based on the use of magnetite, which forms long chains and serves as a magnetic dipole and has been found in organisms such as bats7. The other hypothesis is based on a light-dependent magnetic response utilizing the cryptochromephotoreceptor8. While the predominant hypothesis is that fruit flies use cryptochrome to detect magnetic fields1-6, experimental results have shown that most invertebrates use magnetite or both magnetite and cryptochrome

It's cool to be dominant : social status alters short-term risks of heat stress

Climate change has the potential to trigger social change. As a first step towards understanding mechanisms determining the vulnerability of animal societies to rising temperatures, we investigated interactions between social rank and thermoregulation in three arid-zone bird species: fawn-coloured lark (Mirafra africanoides, territorial); African red-eyed bulbul (Pycnonotus nigricans, loosely social) and sociable weaver (Philetairus socius, complex cooperative societies). We assessed relationships between body temperature (Tb), air temperature (Ta) and social rank in captive groups in the Kalahari Desert. Socially dominant weavers and bulbuls had lower mean Tb than subordinate conspecifics, and dominant individuals of all species maintained more stable Tb as Ta increased. Dominant bulbuls and larks tended to monopolise available shade, but dominant weavers did not. Nevertheless, dominantweavers thermoregulated more precisely, despite expending no more behavioural effort on thermoregulation than subordinates. Increasingly unequal risks associated with heat stress may have implications for the stability of animal societies in warmer climates.This study was supported by National Science Foundation Peer Grant no. PGA- 2000003431 to A.E.M., and funding from the DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology to S.J.C. and M.L.T.http://jeb.biologists.org2018-05-30am2017Zoology and Entomolog

A surrogate model for the economic evaluation of renewable hydrogen production from biomass feedstocks via supercritical water gasification

Supercritical water gasification is a promising technology for renewable hydrogen production from high moisture content biomass. This work produces a machine learning surrogate model to predict the Levelised Cost of Hydrogen over a range of biomass compositions, processing capacities, and geographic locations. The model is published to facilitate early-stage economic analysis (doi.org/10.6084/m9.figshare.22811066). A process simulation using the Gibbs reactor provided the training data using 40 biomass compositions, five processing capacities (10–200 m3/h), and three geographic locations (China, Brazil, UK). The levelised costs ranged between 3.81 and 18.72 $/kgH2 across the considered parameter combinations. Heat and electricity integration resulted in low process emissions averaging 0.46 kgCO2eq/GJH2 (China and Brazil), and 0.37 kgCO2eq/GJH2 (UK). Artificial neural networks were most accurate when compared to random forests and support vector regression for the surrogate model during cross-validation, achieving an accuracy of MAPE: 0.99 on the test set

Unravelling anomalous mass transport in miscible liquids

The dissolution dynamics between miscible liquids play a key role in many industrial, biological and environmental processes, including solvent-induced phase transformations such as the formation of polymer membranes or antisolvent crystallisation. The “common” current intuition that guides the design of diffusion processes in miscible liquids is rooted in Fick’s law. This hypothesis generally holds when the system is close to equilibrium and behaves like an ideal mixture. However, Fickian diffusion has limited applicability far from equilibrium, and many systems display “anomalous” behaviours such as uphill diffusion [1] or the Ouzo effect [2]. Despite the importance of diffusion processes, the mechanisms underlying anomalous mass transfer are still poorly understood [3]. This work provides a direct microscopic view into highly localized anomalous pathways that can occur during the mixing of miscible fluids. Results will be presented for a model system of glycine-water-ethanol that represents a typical antisolvent crystallisation process where anomalous mass transport can have significant impacts on the critical quality attributes of the resulting crystalline product. We have deployed a novel experimental setup that includes a microfluidic flow cell that is monitored using a confocal Raman microscope, enabling the measurement of spectral maps of the mixing of the solution and antisolvent streams. These maps allow for the evolution of the composition of the multicomponent fluid to be determined as mixing progresses. From the measured spectral maps, the equilibration trajectories of the mixing solution and antisolvent streams can be determined, providing information on what regions of the phase diagrams are accessed during the mixing process, while also revealing the conditions that lead to surprising diffusive behaviours. This work provides new insight into the underlying mechanisms of anomalous mass transport and a better understanding of the equilibration pathways that can occur during antisolvent crystallization. References [1] R. Krishna; Uphill diffusion in multicomponent mixtures, Chem. Soc. Rev., 44, 2812-2836 (2015). [2] S. A. Vitale, and J. L. Katz; Liquid droplet dispersions formed by homogeneous liquid-liquid nucleation: “the ouzo effect”, Langmuir, 19, 4105-4110 (2003) [3] A. Vorobev: Dissolution dynamics of miscible liquid/liquid interfaces, Curr. Opin. Colloid Interface Sci., 19, 300-308 (2014)

The influence of transition metal solutes on dislocation core structure and values of Peierls stress and barrier in tungsten

Several transition metals were examined to evaluate their potential for improving the ductility of tungsten. The dislocation core structure and Peierls stress and barrier of $1/2$ screw dislocations in binary tungsten-transition metal alloys (W$_{1-x}$TM$_{x}$) were investigated using first principles electronic structure calculations. The periodic quadrupole approach was applied to model the structure of $1/2$ dislocation. Alloying with transition metals was modeled using the virtual crystal approximation and the applicability of this approach was assessed by calculating the equilibrium lattice parameter and elastic constants of the tungsten alloys. Reasonable agreement was obtained with experimental data and with results obtained from the conventional supercell approach. Increasing the concentration of a transition metal from the VIIIA group, i.e. the elements in columns headed by Fe, Co and Ni, leads to reduction of the $C^\prime$ elastic constant and increase of elastic anisotropy A=$C_{44}/C^\prime$. Alloying W with a group VIIIA transition metal changes the structure of the dislocation core from symmetric to asymmetric, similar to results obtained for W$_{1-x}$Re$_{x}$ alloys in the earlier work of Romaner {\it et al} (Phys. Rev. Lett. 104, 195503 (2010))\comments{\cite{WRECORE}}. In addition to a change in the core symmetry, the values of the Peierls stress and barrier are reduced. The latter effect could lead to increased ductility in a tungsten-based alloy\comments{\cite{WRECORE}}. Our results demonstrate that alloying with any of the transition metals from the VIIIA group should have similar effect as alloying with Re.Comment: 12 pages, 8 figures, 3 table

Development of an open-source carbon footprint calculator of the UK craft brewing value chain

Craft breweries may fall behind large brewing companies in reducing the carbon footprints of their value chains due to limited resources, financial constraints, and a lack of technical knowledge to fully understand their emissions. However, by increasing their awareness of the impact of their entire value chains, craft breweries can accelerate the decarbonisation of the industry by creating competition among breweries to appeal to environmentally conscious consumers. This work developed a freely available carbon calculator (10.6084/m9.figshare.22758692) using transparent, open-source data which may be used for benchmarking and identifying opportunities for emission reductions in UK craft breweries as well as providing a reference point for future carbon footprint analyses of global brewing value chains. The carbon footprint for craft brewing was calculated for a wide range of packaging types across three realistic scenarios (low, medium, and high carbon footprints) based on collected data and addresses the discrepancies between values reported in previous literature. Overall, the calculated carbon footprints ranged between 205 (20 L steel kegs, low carbon footprint scenario) and 1483 (single-use, 0.33 L glass bottles, high carbon footprint scenario) gCO2e per litre of beer. Novel hotspots (including wort boiling, the packaging process in a brewery, and the contribution of secondary and tertiary packaging) were identified. The overwhelming contribution of Scope 3 emissions (contributing between 57 and 95 % of the total carbon footprint) further emphasised the need to provide increased knowledge to craft breweries

Using a pragmatically adapted, low-cost contingency management intervention to promote heroin abstinence in individuals undergoing treatment for heroin use disorder in UK drug services (PRAISE): a cluster randomised trial

Introduction: Most individuals treated for heroin use disorder receive opioid agonist treatment (OAT)(methadone or buprenorphine). However, OAT is associated with high attrition and persistent, occasional heroin use. There is some evidence for the effectiveness of contingency management (CM), a behavioural intervention involving modest financial incentives, in encouraging drug abstinence when applied adjunctively with OAT. UK drug services have a minimal track record of applying CM and limited resources to implement it. We assessed a CM intervention pragmatically adapted for ease of implementation in UK drug services to promote heroin abstinence among individuals receiving OAT. Design: Cluster randomised controlled trial. Setting and participants: 552 adults with heroin use disorder (target 660) enrolled from 34 clusters (drug treatment clinics) in England between November 2012 and October 2015. Interventions: Clusters were randomly allocated 1:1:1 to OAT plus 12× weekly appointments with: (1) CM targeted at opiate abstinence at appointments (CM Abstinence); (2) CM targeted at on-time attendance at appointments (CM Attendance); or (3) no CM (treatment as usual; TAU). Modifications included monitoring behaviour weekly and fixed incentives schedule. Measurements: Primary outcome: heroin abstinence measured by heroin-free urines (weeks 9–12). Secondary outcomes: heroin abstinence 12 weeks after discontinuation of CM (weeks 21–24); attendance; self-reported drug use, physical and mental health. Results: CM Attendance was superior to TAU in encouraging heroin abstinence. Odds of a heroin-negative urine in weeks 9–12 was statistically significantly greater in CM Attendance compared with TAU (OR=2.1; 95% CI 1.1 to 3.9; p=0.030). CM Abstinence was not superior to TAU (OR=1.6; 95% CI 0.9 to 3.0; p=0.146) or CM Attendance (OR=1.3; 95% CI 0.7 to 2.4; p=0.438) (not statistically significant differences). Reductions in heroin use were not sustained at 21–24 weeks. No differences between groups in self-reported heroin use. Conclusions: A pragmatically adapted CM intervention for routine use in UK drug services was moderately effective in encouraging heroin abstinence compared with no CM only when targeted at attendance. CM targeted at abstinence was not effective. Trial registration number: ISRCTN 01591254

Hot days are associated with short-term adrenocortical responses in a southern African arid-zone passerine bird

Relatively little effort has been directed towards elucidating the role of physiological stress pathways in mediating avian responses to global heating. For free-ranging southern pied babblers, Turdoides bicolor, daily maximum air temperatures (Tmax) between ∼35 and ∼40°C result in reduced foraging efficiency, loss of body mass and compromised breeding success. We tested the hypothesis that very hot days are experienced as stressors by quantifying relationships between Tmax and faecal glucocorticoid metabolite (fGCM) levels in naturally excreted droppings. On days when Tmax<38°C, fGCM levels were independent of Tmax (mean±s.d. 140.25±56.92 ng g−1 dry mass). At Tmax>38°C, however, fGCM levels increased linearly with Tmax and averaged 190.79±70.13 ng g−1 dry mass. The effects of Tmax on fGCM levels did not carry over to the following morning, suggesting that very hot days are experienced as acute stressors.The DSI-NRF Centre of Excellence at the FitzPatrick Institute for African Ornithology, the University of Cape Town, the Ernest Oppenheimer Memorial Trust, the British Ornithologists’ Union, the Australian Research Council and the National Research Foundation of South Africa.http://jeb.biologists.org2022-05-15am2022Mammal Research InstituteZoology and Entomolog

Positive reinforcement targeting abstinence in substance misuse (PRAISe): Study protocol for a Cluster RCT &amp; process evaluation of contingency management

There are approximately 256,000 heroin and other opiate users in England of whom 155,000 are in treatment for heroin (or opiate) addiction. The majority of people in treatment receive opiate substitution treatment (OST) (methadone and buprenorphine). However, OST suffers from high attrition and persistent heroin use even whilst in treatment. Contingency management (CM) is a psychological intervention based on the principles of operant conditioning. It is delivered as an adjunct to existing evidence based treatments to amplify patient benefit and involves the systematic application of positive reinforcement (financial or material incentives) to promote behaviours consistent with treatment goals. With an international evidence base for CM, NICE recommended that CM be implemented in UK drug treatment settings alongside OST to target attendance and the reduction of illicit drug use. While there was a growing evidence base for CM, there had been no examination of its delivery in UK NHS addiction services. The PRAISe trial evaluates the feasibility, acceptability, clinical and cost effectiveness of CM in UK addiction services. It is a cluster randomised controlled effectiveness trial of CM (praise and financial incentives) targeted at either abstinence from opiates or attendance at treatment sessions versus no CM among individuals receiving OST. The trial includes an economic evaluation which explores the relative costs and cost effectiveness of the two CM intervention strategies compared to TAU and an embedded process evaluation to identify contextual factors and causal mechanisms associated with variations in outcome. This study will inform UK drug treatment policy and practice. Trial registration ISRCTN 01591254

Anthropological contributions to historical ecology: 50 questions, infinite prospects.

This paper presents the results of a consensus-driven process identifying 50 priority research questions for historical ecology obtained through crowdsourcing, literature reviews, and in-person workshopping. A deliberative approach was designed to maximize discussion and debate with defined outcomes. Two in-person workshops (in Sweden and Canada) over the course of two years and online discussions were peer facilitated to define specific key questions for historical ecology from anthropological and archaeological perspectives. The aim of this research is to showcase the variety of questions that reflect the broad scope for historical-ecological research trajectories across scientific disciplines. Historical ecology encompasses research concerned with decadal, centennial, and millennial human-environmental interactions, and the consequences that those relationships have in the formation of contemporary landscapes. Six interrelated themes arose from our consensus-building workshop model: (1) climate and environmental change and variability; (2) multi-scalar, multi-disciplinary; (3) biodiversity and community ecology; (4) resource and environmental management and governance; (5) methods and applications; and (6) communication and policy. The 50 questions represented by these themes highlight meaningful trends in historical ecology that distill the field down to three explicit findings. First, historical ecology is fundamentally an applied research program. Second, this program seeks to understand long-term human-environment interactions with a focus on avoiding, mitigating, and reversing adverse ecological effects. Third, historical ecology is part of convergent trends toward transdisciplinary research science, which erodes scientific boundaries between the cultural and natural