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An array of compact, high-bandwidth (>200 MHz) and low-cost optical photodiodes has been developed and implemented on the PHASe MApping (PHASMA) experiment. Using purpose-built electronics, an array of 16 photodetectors was constructed and used to monitor broadband (1–5 MHz) fluctuations in light intensity emitted by flux ropes undergoing electron-only magnetic reconnection. These measurements reveal a swath of oscillatory behavior, including wave propagation inward toward the diffusion region at approximately the local electron Alfvén speed. Custom 3D-printed collection optics and mounting hardware allow quick reconfiguration of the array for radial or axial measurements. The electronics design is flexible enough to be used with other current-sourcing transducers, such as avalanche photodiodes; silicon photomultipliers; and infrared, x-ray, and UV photodiodes. A noise-rejecting electrical layout allows for low-noise operation close to pulsed plasma discharges. A 16-channel, 64-pixel tomographic array was constructed and initial reconstructions are presented. [ABSTRACT FROM AUTHOR]

This study employs a fast camera with frame rates up to 900,000 fps to measure the transfer of energy across spatial scales in helicon source plasmas and during flux rope mergers and the measurement of azimuthal mode structures in helicon plasmas. By extracting pixel-scale dispersion relations and power spectral density (PSD) measurements, we measure the details of turbulent wave modes and energy distribution across a broad range of spatial scales within the plasma. We confirm the presence of drift waves in helicon plasmas, as well as the existence of strong dissipation regions in the PSD at electron skin depth scales for both helicon and flux rope merger experiments. This approach overcomes many limitations of conventional probes, providing high spatial and temporal resolution, without perturbing the plasma. [ABSTRACT FROM AUTHOR]

Byline: Sonu. Yadav, Poonam. Joshi, Ujjwal. Dahiya, Dalim. Baidya, Ravinder. Goswami, Randeep. Guleria, Ramakrishnan. Lakshmy Background and Aims: Effect of serum 25-hydroxy vitamin D (25[OH] D) levels on the recovery [...]

Olfaction is a widespread mode of communication in mammals. The volatile organic compounds (VOCs) in biological samples such as scat and urine give them either a repellent property to warn prey or an attractant property to communicate reproductive, social, and territorial status to conspecifics. The aim of this study was to determine whether there are VOC differences in the scat of a dingo compared to that of a domestic German Shepherd Dog (GSD). We standardised the diet for 10 days and then collected scat from 14 dingoes and 11 GSDs. Using headspace solid phase microextraction (HS-SPME) with gas chromatography–mass spectrometry (GC-MS), we characterised VOCs present in the dingo scat and compared the composition with those of GSDs. We identified 58 significant VOCs out of a total of 154 VOCs identified in both dingoes and GSDs. Of these, 12 were significantly higher in the scat of dingoes and 46 elevated in the GSD. Of the 12 elevated in the dingo, three were unique and present in high concentration (>10 ng/g), four were elevated and present in high concentration and five were present at low concentrations (<10 ng/g). We suggest that the detected differences show potential to be incorporated into dingo management strategies. Integrated pest management is a recommended control method for wild dogs in Australia. This study takes the first step in identifying potential population-specific chemical cues in scat as a step towards supplementing existing strategies with chemical approaches aimed at excluding pure dingoes from agricultural lands. Photograph by Barry Eggleton. [ABSTRACT FROM AUTHOR]

Dogs were the first animal to become domesticated by humans, and they represent a classic model system for unraveling the processes of domestication. We compare Australian dingo eye contact and socialization with Basenji and German Shepherd dog (GSD) breeds. Australian dingoes arrived in Australia 5,000–8,000 BP, and there is debate whether they were domesticated before their arrival. The Basenji represents a primitive breed that diverged from the remaining breeds early in the domestication process, while GSDs are a breed dog selected from existing domestic dogs in the late 1800s. We conducted a 4-phase study with unfamiliar and familiar investigators either sitting passively or actively calling each canid. We found 75% of dingoes made eye contact in each phase. In contrast, 86% of Basenjis and 96% of GSDs made eye contact. Dingoes also exhibited shorter eye-gaze duration than breed dogs and did not respond to their name being called actively. Sociability, quantified as a canid coming within 1 m of the experimenter, was lowest for dingoes and highest for GSDs. For sociability duration, dingoes spent less time within 1 m of the experimenter than either breed dog. When compared with previous studies, these data show that the dingo is behaviorally intermediate between wild wolves and Basenji dogs and suggest that it was not domesticated before it arrived in Australia. However, it remains possible that the accumulation of mutations since colonization has obscured historical behaviors, and dingoes now exist in a feralized retamed cycle. Additional morphological and genetic data are required to resolve this conundrum. [ABSTRACT FROM AUTHOR]

Local adaptation can occur at small spatial scales relative to the dispersal capacity of species. Alpine ecosystems have sharp environmental clines that offer an opportunity to investigate the effects of fine‐scale shifts in species' niche breadth on adaptive genetic processes. Here we examine two grasshopper species endemic to the Australian Alps (Kosciuscola spp.) that differ in elevational niche breadth: one broader, K. usitatus (1400–2200 m), and one narrower, K. tristis (1600–2000 m). We examine signatures of selection with respect to environmental and morphological variables in two mountain regions using FST outlier tests and environmental association analyses (EAAs) applied to single nucleotide polymorphism (SNP) data (K. usitatus: 9017 SNPs, n = 130; K. tristis: 7363 SNPs, n = 135). Stronger genetic structure was found in the more narrowly distributed K. tristis, which showed almost twice the number of SNPs under putative selection (10.8%) compared with K. usitatus (5.3%). When examining SNPs in common across species (n = 3058), 260 SNPs (8.5%) were outliers shared across species, and these were mostly associated with elevation, a proxy for temperature, suggesting parallel adaptive processes in response to climatic drivers. Additive polygenic scores (an estimate of the cumulative signal of selection across all candidate loci) were nonlinearly and positively correlated with elevation in both species. However, a steeper correlation in K. tristis indicated a stronger signal of spatially varying selection towards higher elevations. Our study illustrates that the niche breadth of co‐occurring and related species distributed along the same environmental cline is associated with differences in patterns of microgeographical adaptation. [ABSTRACT FROM AUTHOR]