Complex and Transitive Synchronization in a Frustrated System of Calling Frogs

This letter reports synchronization phenomena and mathematical modeling on a frustrated system of living beings, or Japanese tree frogs (Hyla japonica). While an isolated male Japanese tree frog calls nearly periodically, he can hear sounds including calls of other males. Therefore, the spontaneous calling behavior of interacting males can be understood as a system of coupled oscillators. We construct a simple but biologically reasonable model based on the experimental results of two frogs, extend the model to a system of three frogs, and theoretically predict the occurrence of rich synchronization phenomena, such as triphase synchronization and 1:2 antiphase synchronization. In addition, we experimentally verify the theoretical prediction by ethological experiments on the calling behavior of three frogs and time series analysis on recorded sound data. Note that the calling behavior of three male Japanese tree frogs is frustrated because almost perfect antiphase synchronization is robustly observed in a system of two male frogs. Thus, nonlinear dynamics of the three-frogs system should be far from trivial

Less-invasive Treatment for Group A Streptococcal Fasciitis with Rapid Antigen Detection Test and Collagen/Gelatin Sponge

Patients with severe group A Streptococcus (GAS) induced necrotizing soft tissue infection sometimes develop Streptococcal toxic shock syndrome, which is a life-threatening condition with an extremely high fatality rate. Obtaining survival is the most important goal; however, an early diagnosis for debridement surgery and quick granulation formation for skin grafting surgery can better preserve the extremity functions. The patient was a 47-year-old man with a history of atopic dermatitis who presented with GAS-induced necrotizing soft tissue infection in his left lower extremity. His vital signs indicated shock, and he was diagnosed with streptococcal toxic shock syndrome. Emergency surgery was performed with his body pressure maintained with noradrenaline. Intraoperatively, rapid antigen detection tests (RADTs) were negative in the medial thigh and positive in the lower leg, which helped in decision-making regarding the area of aggressive debridement surgery. The wound culture results matched the intraoperative rapid antigen detection test results. A collagen/gelatin sponge with the sustained release of basic fibroblast growth factor was used as an artificial dermis before skin grafting. Excellent granulation was obtained, and skin grafting surgery was performed on the 11th day after collagen/gelatin sponge placement. He was discharged home on the 42nd day with normal lower extremity functions. First, an intraoperative diagnosis using GAS-rapid antigen detection tests with an appropriate sampling method from small incisions avoided excessive surgical debridement. Second, collagen/gelatin sponge with the sustained release of basic fibroblast growth factor promoted quick granulation tissue formation for wound bed preparation. These efforts resulted in the successful less-invasive treatment of a patient with streptococcal toxic shock syndrome caused by GAS-induced necrotizing soft tissue infection

Morphological Changes and Durability of Skin and Mucosal Flaps in Intraoral and Pharyngeal Reconstructions: Long-term Follow-up and Literature Review for Potential Second Carcinomas

The long-term changes in tissues implanted in the oral cavity and pharynx after head and neck reconstruction have not been fully evaluated. This study aimed to clarify the morphological changes, long-term durability, and potential for secondary carcinogenesis in such tissues. In our single-center study, the rough morphological changes in 54 cases of intraoral and pharyngeal skin and mucosal flaps were evaluated more than 10 years after flap transfer. In addition, the literature on the development of second carcinomas from skin flaps was reviewed. The mean follow-up period for transferred flaps was 148 months. The reconstruction areas and the probability of morphological changes were significantly correlated (p=0.006), especially in cases with tongue, lower gingiva, and buccal mucosal reconstruction. Free jejunal flap surfaces were well maintained, whereas tubed skin flaps showed severe morphological changes in cases with pharyngeal reconstruction. None of the flaps in our series developed second primary carcinomas. Skin flaps generally had good durability for > 10 years in intraoral environments, while mucosal flaps had better durability for pharyngeal reconstruction. Second squamous carcinomas arising from skin flaps are extremely rare; however, surgeons should take this possibility into consideration and conduct meticulous and long-term follow-up

Magnetic properties of new filled skutterudite compound BaFe4As12

The magnetic, electrical and thermal properties of a new As-based alkaline-earth-filled skutterudite compound BaFe4As12 prepared under high pressure have been studied at low temperatures. The temperature dependence of the electrical resistivity for BaFe4As12 reveals a metallic behavior. Any anomalies accompanied by phase transition were not observed down to 2K. A broad maximum of magnetic susceptibility around 50 K and a large electronic specific heat coefficient of 62 mJ/molK2 suggest that BaFe4As12 is a nearly ferromagnetic metal with spin fluctuations of Fe 3d electrons

Magnetically Tuned Continuous Transition from Weak to Strong Coupling in Terahertz Magnon Polaritons

Depending on the relative rates of coupling and dissipation, a light-matter coupled system is either in the weak- or strong-coupling regime. Here, we present a unique system where the coupling rate continuously increases with an externally applied magnetic field while the dissipation rate remains constant, allowing us to monitor a weak-to-strong coupling transition as a function of magnetic field. We observed a Rabi splitting of a terahertz magnon mode in yttrium orthoferrite above a threshold magnetic field of ~ 14 T. Based on a microscopic theoretical model, we show that with increasing magnetic field the magnons transition into magnon polaritons through an exceptional point, which will open up new opportunities for in situ control of non-Hermitian systems

Sound imaging of nocturnal animal calls in their natural habitat.

We present a novel method for imaging acoustic communication between nocturnal animals. Investigating the spatio-temporal calling behavior of nocturnal animals, e.g., frogs and crickets, has been difficult because of the need to distinguish many animals' calls in noisy environments without being able to see them. Our method visualizes the spatial and temporal dynamics using dozens of sound-to-light conversion devices (called "Firefly") and an off-the-shelf video camera. The Firefly, which consists of a microphone and a light emitting diode, emits light when it captures nearby sound. Deploying dozens of Fireflies in a target area, we record calls of multiple individuals through the video camera. We conduct two experiments, one indoors and the other in the field, using Japanese tree frogs (Hyla japonica). The indoor experiment demonstrates that our method correctly visualizes Japanese tree frogs' calling behavior. It has confirmed the known behavior; two frogs call synchronously or in anti-phase synchronization. The field experiment (in a rice paddy where Japanese tree frogs live) also visualizes the same calling behavior to confirm anti-phase synchronization in the field. Experimental results confirm that our method can visualize the calling behavior of nocturnal animals in their natural habitat

Recent Advances in the Treatment of Colorectal Cancer: A Review

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