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Night-time light can have profound ecological effects, even when the source is natural moonlight. The impacts of light can, however, vary substantially by taxon, habitat and geographical region. We used a custom machine learning model built with the Python package Koogu to investigate the in situ effects of moonlight on the calling activity of neotropical forest katydids over multiple years. We prioritised species with calls that were commonly detected in human annotated data, enabling us to evaluate model performance. We focused on eight species of katydids that the model identified with high precision (generally greater than 0.90) and moderate-to-high recall (minimum 0.35), ensuring that detections were generally correct and that many calls were detected. These results suggest that moonlight has modest effects on the amount of calling, with the magnitude and direction of effect varying by species: half of the species showed positive effects of light and half showed negative. These findings emphasize the importance of understanding natural history for anticipating how biological communities respond to moonlight. The methods applied in this project highlight the emerging opportunities for evaluating large quantities of data with machine learning models to address ecological questions over space and time. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'. [ABSTRACT FROM AUTHOR]

Passive acoustic monitoring (PAM) is a powerful tool for studying ecosystems. However, its effective application in tropical environments, particularly for insects, poses distinct challenges. Neotropical katydids produce complex species-specific calls, spanning mere milliseconds to seconds and spread across broad audible and ultrasonic frequencies. However, subtle differences in inter-pulse intervals or central frequencies are often the only discriminatory traits. These extremities, coupled with low source levels and susceptibility to masking by ambient noise, challenge species identification in PAM recordings. This study aimed to develop a deep learning-based solution to automate the recognition of 31 katydid species of interest in a biodiverse Panamanian forest with over 80 katydid species. Besides the innate challenges, our efforts were also encumbered by a limited and imbalanced initial training dataset comprising domain-mismatched recordings. To overcome these, we applied rigorous data engineering, improving input variance through controlled playback re-recordings and by employing physics-based data augmentation techniques, and tuning signal-processing, model and training parameters to produce a custom well-fit solution. Methods developed here are incorporated into Koogu, an open-source Python-based toolbox for developing deep learning-based bioacoustic analysis solutions. The parametric implementations offer a valuable resource, enhancing the capabilities of PAM for studying insects in tropical ecosystems. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'. [ABSTRACT FROM AUTHOR]

Objective/Hypothesis: We explored the following hypotheses in a cohort of patients undergoing injection laryngoplasty: (1) glottic insufficiency affects voluntary cough airflow dynamics and restoring glottic competence may improve parameters of cough strength, (2) cough strength can be inferred from cough acoustic signal, and (3) glottic competence changes cough sounds and correlates with spectrogram morphology. Study Type/Design: Prospective interventional study. Methods: Subjects with glottic insufficiency secondary to unilateral vocal fold paresis, paralysis, or atrophy, and scheduled for injection laryngoplasty completed an instrumental assessment of voluntary cough airflow using a pneumotachometer and a protocolized voluntary cough sound recording. A Wilcoxon signed‐rank test was used to compare the differences between pre‐ and post‐injection laryngoplasty in airflow and acoustic measures. A Spearman rank‐order correlation was used to evaluate the association between airflow and acoustic cough measures. Results: Twenty‐five patients (13F:12M, mean age 68.8) completed voluntary cough airflow measurements and 22 completed cough sound recordings. Following injection laryngoplasty, patients had a statistically significant decreased peak expiratory flow rise time (PEFRT) (mean change: −0.03 s, SD: 0.06, p = 0.04) and increased cough volume acceleration (mean change: 13.1 L/s2, SD: 33.9, p = 0.03), suggesting improved cough effectiveness. Correlation of cough acoustic measures with airflow measures showed a weak relationship between PEFRT and acoustic energy (coefficient: −0.31, p = 0.04) and peak power density (coefficient: −0.35, p = 0.02). Conclusions: Our study thus indicates that injection laryngoplasty may help avert aspiration in patients with glottic insufficiency by improving cough effectiveness and that improved cough airflow measures may be tracked with cough sounds. Level of Evidence: 3 Laryngoscope, 133:S1–S14, 2023 [ABSTRACT FROM AUTHOR]

Ballistocardiograms (BCGs) are graphical representations of the recoil from the pumping action of the heart. Introductory mechanics and a basic knowledge of the circulatory system are sufficient to understand the key features of a BCG. BCGs with adequate detail for instructional purposes may be produced easily and rapidly using hardware (a force plate) and software common to introductory physics labs. The interdisciplinary nature of this exercise is a particularly attractive feature. We have used it as a demonstration in a course on mechanics for nonphysics majors as well as for visiting high school students, and indicate here possible ways to incorporate it into upper-level physics or biomechanics courses.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2008.04.024 Byline: Tom D. Schultz, Christopher N. Anderson, Laurel B. Symes Abstract: The colours of male coenagrionid damselflies have been interpreted by some as intraspecific signals that reduce intrasexual harassment by advertising the unprofitability of pursuing conspecific males as potential mates. As visual cues, male colours should be conspicuous to other males under the specific light environments where males search for females. We tested this prediction by using spectroradiometry and two models of damselfly colour vision to determine the chromatic and achromatic contrast of males from six species of Enallagma damselflies with pond backgrounds under the ambient light conditions when each species was most active. The males of five species were active at the time when their colour was most conspicuous against aquatic vegetation. Three blue species were most active and attained their highest levels of contrast during midday, while species that became active in late afternoon or evening reflected longer wavelengths and increased in brightness contrast under low sun angles. A sixth species, Enallagma pictum, departed from this pattern. We propose that colour may serve as a signal of both sexual and species identity among males. Author Affiliation: Department of Biology, Denison University, Granville, Ohio, U.S.A. Article History: Received 16 February 2008; Revised 13 March 2008; Accepted 7 April 2008 Article Note: (miscellaneous) MS. number: A08-00093