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Solar flare ion temperatures
No full textThis Letter proposes that the ion temperature is several times the local electron temperature in the hot onset phase and in the above-the-loop region of solar flares. The Letter considers: the evidence of spectral line Doppler widths (“nonthermal” broadening); evidence for “universal” ion and electron temperature increase scaling relations for magnetic reconnection in the solar wind, Earth’s magnetopause, Earth’s magnetotail, and numerical simulations; and thermal equilibration times for onset and above-the-loop densities, which are much longer than previous estimates based on soft X-ray flare loops. We conclude that the ion temperature is likely to reach 60 MK or greater and that it may represent a substantial part of spectral line widths, significantly contributing to solving the long-standing issue of the excess nonthermal broadening in flare lines
Ukraine’s drone air war has given Zelensky additional bargaining power with Putin – new research
No full textApplying movement ecology models to comparative cognition experiments:a field test in hummingbirds
No full textTraditionally, evidence for spatial learning in animals involves experiments; however, tools developed for analysing tracking data are increasingly being used to infer the use of spatial memory and other cognitive processes in animal movements. In this study, we combined these statistical models with field experiments to analyse how patterns of hummingbird movements change as birds learn a rewarded location. Using hidden Markov models (HMMs), we used both changes in two movement states as well as experimental behavioural measures of spatial memory to determine how searching performance and behaviour changed as birds gained experience and how important local landmarks were for guiding search. Regardless of whether birds had a single training trial to learn a flower's location or 12 repeated trials, hummingbirds learned the location of the flower although performance suffered when we removed the local landmarks. While the hovering locations suggested that removing landmarks led to a slight decrease in accuracy compared with when landmarks were present, the HMMs suggest that this was part of a larger shift from a memory-led search strategy to a more systematic searching process. Our results suggests that models used in movement ecology could provide a valuable tool for experiments in comparative cognition
The Andean khipus:an information system made of string
No full textStoring, sharing, and controlling information is a crucial factor in the success of a centralized state. Yet the Inkas, the largest empire in the pre-Hispanic Americas, did not use writing in a conventional sense. Instead, they utilized khipus: a colorful knotted string technology, unique among global information systems. This chapter delves into the complex history of khipus, challenging conventional notions of information storage. Spanning a millennium of khipu use, this discussion traces the khipus’ origins during Wari Empire (c. 600–900 CE) before considering the role played by khipus in the Inka state. The narrative then extends into the colonial and republican periods, highlighting the enduring relevance of these enigmatic artifacts. The chapter offers a nuanced exploration of khipu morphology and of the key scholarship that has shaped our knowledge about this medium. Unraveling their intricate nature, this discussion provides essential insights into khipus’ cultural and historical significance, and offers a comprehensive understanding of their multifaceted role in the history of information
Long‐Term depth records of satellite‐tagged northern bottlenose whales reveal extraordinary dive capabilities
No full textStudying the baseline behavior of deep‐diving mammals can substantially improve our understanding of these species' ecology and provide important benchmarks to evaluate effects of changes in climate and anthropogenic activities. Despite being the most abundant beaked whale in the Arctic and subarctic, information on the behavior of northern bottlenose whales (Hyperoodon ampullatus) is limited. This study used records from 13 satellite tags deployed off Jan Mayen in June–July 2014–2016 to provide an extensive description of the dive behavior of Hyperoodon for the Nordic Seas. A total of 8372 dives, collected over 224 days (or 5376 h), were analyzed. The whales performed extreme dives of up to 2288 m deep and 98 min long—deeper and longer than previously reported for behavior in presumed undisturbed contexts. Individuals spent on average 18% of the time at depths shallower than 40 m, and 22%, 47%, and 12% in epi‐, meso‐, and bathypelagic dives, respectively. Epipelagic dives averaged 123 m (s.d.: 46 m) in depth and 11 min (5 min) in duration. Mesopelagic dives averaged 441 m (217 m) and 24 min (11 min) and were performed at a mean rate of 1.46 h−1. Bathypelagic dives averaged 1487 m (366 m) and 55 min (13 min) and were performed at a mean rate of 0.23 h−1. The distribution of dive depths was less bimodal than typically reported for other beaked whales, and all dive profiles contained periods of continuous, consecutive deep dives. Benthic diving occurred at meso‐ and especially bathypelagic depths and was individual specific, varying from 8% to 51% of the animal's bathypelagic dives. Overall, our findings demonstrate that northern bottlenose whales have extraordinary capabilities to dive, and presumably feed, throughout the water column including at the sea floor. High rates of deep dives highlight the importance of the Iceland and Norwegian Seas to this population of deep‐sea predators
Modelling the 3D atmospheric structure of the cold Jupiter WD1856+534b orbiting a white dwarf
No full textWD-1856b+534b (WD-1856b) is to date the only detected cold Jupiter outside of our Solar System. This cold Jupiter can provide useful information about the cold giants in our Solar System. Recent JWST observations have targeted WD-1856b, with more scheduled in the near future. To support the interpretation of these observations, we simulated WD-1856b using a three-dimensional (3D) General Circulation Model (GCM) and produced synthetic emission spectra of the planet. We used the Exo-FMS GCM with correlated-k radiative transfer (RT) and mixing-length theory (MLT). In addition, we included abundances of 13 chemical species using the thermochemical kinetic model mini-chem. Because there are substantial uncertainties in the metallicity and internal temperature of WD-1856b, we ran simulations with 1x, 10x, and 100x solar compositions and at low and high internal temperatures (100 K and 500 K). We generated emission spectra and brightness temperature curves with the GCM output using the 3D Monte Carlo radiative-transfer code gCMCRT. Our results suggest larger volume mixing ratios (VMR) of CO and CO2 with a warmer core at higher metallicity. With a colder core, H2O and CH4 become more relevant and increase to 0.01 VMR at 100x Solar. We suggest possible H2O cloud formation in the upper atmosphere in the warm 100x solar case and in all cold cases, which may reduce gas phase H2O in the upper atmosphere moderately
Food and/is power:Recent historiographical developments in the histroy of food under fascism
No full textThis historiographical review considers some of the most innovative and influential works published in the growing and dynamic field of food history during fascism over the past decade or so, outlining four important trends and thematic developments within food history and the history of fascism to which these works have contributed. In particular, this literature review points to: 1) the emphasis placed by these works on the political nature and importance of food, its production, procurement, preparation and consumption; 2) the emphasis on exploring the historical trajectories of particular foodstuffs, companies and brands during the period of fascist rule; 3) the focus on the intersectionality of gender and race (alongside other categories) within food histories; and finally, 4) bringing the other three points together, the clear understanding within recent historiography of the centrality of food, and the politics of food, to the negotiating and wielding of power within the fascist state and society
Humans may not have a uniquely enhanced sequence memory:sequence discrimination is facilitated by causal-logical framing in humans and chimpanzees
No full textHumans have been suggested to possess uniquely enhanced memory for sequences, based on sequence discrimination learning (SDL) tasks involving arbitrarily ordered sequences with no functional connection to outcomes. Such tasks underestimate animals' SDL as they lack affordances of real-world situations. We tested whether stimuli causally connected to outcomes facilitate SDL. A total of 13 chimpanzees, 24 capuchin monkeys, 23 squirrel monkeys, 77 adult and 239 juvenile humans completed an AB versus BA, BB and AA task. Humans discriminated causal sequences better than arbitrary ones and one chimpanzee succeeded in the causal frame condition after 324 trials, suggesting that performance gaps in previous studies are partly due to the arbitrariness of sequences (monkeys mostly failed the training). Without causal framing, children found the task difficult until 10-11 years of age. The sequence memory hypothesis needs to be evaluated with a broader set of tasks and account for cultural scaffolding of participants' understanding of task requirements
Footprints of worldwide adaptation in structured populations of <i>Drosophila melanogaster</i> through the expanded DEST 2.0 genomic resource
No full textLarge-scale genomic resources can place genetic variation into an ecologically informed context. To advance our understanding of the population genetics of the fruit fly Drosophila melanogaster, we present an expanded release of the community-generated population genomics resource Drosophila Evolution over Space and Time (DEST 2.0; https://dest.bio/). This release includes 530 high-quality pooled libraries from flies collected across six continents over more than a decade (2009 to 2021), most at multiple time points per year; 211 of these libraries are sequenced and shared here for the first time. We used this enhanced resource to elucidate several aspects of the species' demographic history and identify novel signs of adaptation across spatial and temporal dimensions. For example, we showed that the spatial genetic structure of populations is stable over time, but that drift due to seasonal contractions of population size causes populations to diverge over time. We identified signals of adaptation that vary between continents in genomic regions associated with xenobiotic resistance, consistent with independent adaptation to common pesticides. Moreover, by analyzing samples collected during spring and fall across Europe, we provide new evidence for seasonal adaptation related to loci associated with pathogen response. Furthermore, we have also released an updated version of the DEST genome browser. This is a useful tool for studying spatiotemporal patterns of genetic variation in this classic model system
CAN AI BE FRIENDS? An Innovative Approach to Integrating Generative AI as a Critical Friend in Bahrain Polytechnic's English Foundation Programme
No full textThis practitioner article investigates the innovative implementation of Generative Artificial Intelligence (GAI) as a critical friend in a foundation-level English course at Bahrain Polytechnic. The research explores the use of GAI tools (e.g., ChatGPT, Gemini) over four weeks to enhance students' learning experience, aiming to balance the benefits of GAI with concerns about academic integrity and plagiarism in Higher Education (HE). In this intervention, 17 participants used GAI during class activities, receiving real-time feedback and tailored support, and data collection involved unstructured, non-participant observations of GAI interactions and learners’ reflections submitted via Padlet. Thematic analysis of data revealed changes in classroom dynamics, with quieter classrooms and decreased student-student and student-teacher interactions. The results also highlight that while students initially took longer to complete tasks using GAI, they adapted and became more autonomous over time. The study provides implications for educators on the responsible use of GAI, aiming to reduce the stigma associated with it and promote its ethical integration in HE settings, particularly in teaching English for Academic Purposes (EAP)