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Short-wavelength artificial light at night is increasingly being associated with health and ecological risks. The negative impact of this relatively new source of pollution has been studied intensively in wild birds but to a much lesser extent in captive conspecifics. Using an avian model, our objective was to evaluate the effects of short-wavelength (200 lux at 460 nm) lighting on the body mass and reproductive success of Budgerigars (Melopsittacus undulatus) under captive conditions. Birds were maintained under a naturally increasing photoperiod from March to June, with one daily artificial light at night exposure of increasing duration (0, 30, 60, and 90 min) in the middle of the dark period. During the experiments, birds were monitored monthly for body mass, number of eggs laid, hatching success, and melatonin sulfate levels in droppings. Artificial light at night increased body mass and decreased melatonin sulfate levels as well as the number of eggs and hatching success in a duration dose-dependent manner. Our findings provide further evidence of the potential adverse impact of artificial light at night on captive birds and advocate the need for effective controlling measures for light pollution.

Abstract Imagine being in a crowded room with a cacophony of speakers and having the ability to focus on or remove speech from a specific 2D region. This would require understanding and manipulating an acoustic scene, isolating each speaker, and associating a 2D spatial context with each constituent speech. However, separating speech from a large number of concurrent speakers in a room into individual streams and identifying their precise 2D locations is challenging, even for the human brain. Here, we present the first acoustic swarm that demonstrates cooperative navigation with centimeter-resolution using sound, eliminating the need for cameras or external infrastructure. Our acoustic swarm forms a self-distributing wireless microphone array, which, along with our attention-based neural network framework, lets us separate and localize concurrent human speakers in the 2D space, enabling speech zones. Our evaluations showed that the acoustic swarm could localize and separate 3-5 concurrent speech sources in real-world unseen reverberant environments with median and 90-percentile 2D errors of 15 cm and 50 cm, respectively. Our system enables applications like mute zones (parts of the room where sounds are muted), active zones (regions where sounds are captured), multi-conversation separation and location-aware interaction.

Jihene Sayadi,1 Dhouha Gouider,1 Yasmine Allouche,1 Racem Choura,1 Ines Cherni,1 Malek Sayadi,2 Hend Benneji,2 Imene Zghal,1 Ines Malek,1 Leila Nacef1 1Department A, Hedi Raies Institute of Ophthalmology, Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia; 2Department of Hematology, Aziza Othmana Hospital, Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, TunisiaCorrespondence: Dhouha Gouider, Department A, Hedi Raies Institute of Ophthalmology, Faculty of Medicine of Tunis, University of Tunis El Manar, Bab Saadoun, Tunis, Tunisia, Tel +21640660114, Email dhouhagouider@gmail.comPurpose: To describe ocular manifestations of acute leukemia in a Tunisian cohort and to assess the associations between ophthalmic findings and epidemiological, clinical, and biological features of the disease.Methods: A prospective study included patients newly diagnosed with acute leukemia referred to our clinics between January 2019 and July 2020. All patients underwent a complete ophthalmic evaluation and spectral-domain optical coherence tomography (SD-OCT) at presentation, then every two months during one year. We defined two groups: Group 1 included patients with leukemic ophthalmopathy and group 2 included patients with normal ophthalmic examination.Results: Forty-six patients were enrolled. The mean age of patients was 32.1± 15.3 years. The sex ratio M/F was 1.55 (28 male patients and 18 females). Twenty-nine patients (63%) had acute myeloid leukemia (AML), and 17 (37%) had acute lymphoblastic leukemia (ALL). The average follow-up was 9.1 months (range: 3– 12 months). We observed ophthalmic manifestations in 28 patients (61%). Among them, 17 (61%) had vision-threatening complications. The posterior segment was the most common site of ocular involvement (82% of group1). Primary leukemic infiltration (Disc edema, ptosis, exophthalmos) was present in 13 eyes (14.1%). Twenty-seven eyes (29.3%) had secondary involvement lesions (Subconjunctival hemorrhage, periorbital ecchymosis, retinal/sub-hyaloid hemorrhage, dilated/tortuous veins). Twenty-one eyes (22.8%) showed other ocular manifestations which etiopathogenesis is not yet fully understood (White-centred hemorrhages, cotton-wool spots, serous retinal detachment, hemorrhagic pigment epithelial detachment). Leukemic retinopathy was significantly more frequent in adults (23/39 and 1/7 in adult and pediatric groups, respectively; p=0.003). Patients suffering from AML were more likely to have secondary ocular involvement (20/29 and 7/17 in AML and ALL patients, respectively; p=0.047). Retinal hemorrhages were statistically associated with anemia and thrombocytopenia (p=0.041 and p=0.034; respectively).Conclusion: Leukemic ophthalmopathy seems to be frequent and may lead to severe visual impairment. An ophthalmic assessment complemented with SD-OCT has paramount importance in all newly diagnosed acute leukemic patients.Keywords: acute leukemia, ocular manifestations, leukemic retinopathy, retinal hemorrhage