Publications by authors named "Mitamura H"

Understanding the mechanism by which non-native fish species integrate into native communities is crucial for evaluating the possibility of their establishment success. The genus Pangasianodon, comprising Pangasianodon gigas and Pangasianodon hypophthalmus, has been introduced into reservoirs, which are non-native habitats, for fishery stock enhancement. P.

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  • The study examined the homing behavior of Japanese eels (A. japonica) in a freshwater river in Japan, focusing on how these eels navigate back to their habitats.
  • Researchers used acoustic telemetry to track 18 eels, finding that those over 400 mm in length had a strong tendency to return to their original sampling locations during dark periods.
  • Results indicated that olfactory cues were not significant for short-range homing, suggesting that other mechanisms might be at play for these eels in freshwater environments.
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  • Dietary information from aquatic organisms helps predict interactions and understand ecosystem functionality, especially in freshwater habitats with generalist fish species accessing diverse food sources.
  • This study focuses on striped catfish feeding habits at different life stages, using isotopic and fatty acid analysis to differentiate their food sources from various chains.
  • Findings reveal that adult catfish rely on primary photosynthetic food sources, while juvenile catfish utilize both anoxic decomposition and photosynthetic production, highlighting the importance of anoxic food chains in tropical fish diets.
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Although river-crossing structures can have a detrimental effect on the movement and distribution of anguillid eels (genus Anguilla), they have inhabited locations upstream of river-crossing structures in many rivers. However, the growth stage in which the eels start to climb river-crossing structures remains unclear. In this study, we directly observed, using infrared video camera systems, that the Japanese eel (Anguilla japonica) climbs a low-height vertical weir as a migratory barrier, confirming the ability of eels to climb over a low-height weir within a river.

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We proposed a simple hyperbolic positioning method that does not require solving simultaneous quadratic equations. Moreover, we introduced the mathematical concept of a "pencil" into analytical calculations in the hyperbolic positioning method for a better understanding. In many recent studies using positioning biotelemetry, the specific procedure for intersection calculation of hyperbolas has rarely been described.

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Introduction: Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disease with various neurological manifestations. Corneal endothelial degeneration and optic atrophy have been reported separately; however, there are no reports of corneal endothelial degeneration with optic atrophy.

Cases: Herein, we present four related patients with DRPLA: two patients (69-year-old woman and 80-year-old man) who exhibited both corneal endothelial degeneration and optic atrophy and another two (49- and 51-year-old women, respectively) who exhibited only corneal endothelial degeneration.

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Patients with atrial fibrillation (AF) at the highest risk of progression to heart failure (HF) need to be identified. We investigated whether QRS duration can stratify patients with AF at risk for poor clinical outcomes, including health-related quality of life (HR-QoL). We analyzed data from a multicenter registry-based cohort study of patients with AF.

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Acoustic telemetry (AT) is a rapidly evolving technique used to track the movements of aquatic animals. As the capacity of AT research expands it is important to optimize its relevance to management while still pursuing key ecological questions. A global review of AT literature revealed region-specific research priorities underscoring the breadth of how AT is applied, but collectively demonstrated a lack of management-driven objectives, particularly relating to fisheries, climate change, and protection of species.

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Diffuse large B-cell lymphoma (DLBCL)-associated arrhythmias may be due to cardiac involvement or may be chemotherapy-induced. There have been no reports of significant arrhythmias with normal cardiac function occurring during the complete remission of DLBCL. A 57-year-old female, who had had no history of abnormal electrocardiograms (ECGs) in annual medical checkups, was admitted to our hospital because of low-grade fever, night sweats, and weight loss.

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Introduction: With the advent of perfluorocarbon liquid (PFCL), the success rate of refractory giant retinal tear (GRT) detachment has dramatically improved. PFCL is a very effective tool when used properly, but in GRT detachment, it may move under the retina through the tear, so it is necessary to devise ways to prevent PFCL from migrating under the retina. Ophthalmic endoscope-assisted vitrectomy may reduce the risk of subretinal migration of PFCL, facilitate safer use of PFCL, and increase the success rate of GRT detachment.

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There has been no large multicenter clinical trial on the prognosis of implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D) in Japanese patients with coronary artery disease (CAD). The aim of the present study was to compare differences in the prognoses of Japanese patients with CAD between primary and secondary prevention, and to identify potential predictors of prognosis. We investigated 392 CAD patients (median age 69 years, 90% male) treated with ICD/CRT-D enrolled in the Japan Implantable Devices in CAD (JID-CAD) Registry.

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We show theoretically and experimentally that accurate transport measurements are possible even within the short time provided by pulsed magnetic fields. For this purpose, a new method has been devised, which removes the noise component of a specific frequency from the signal by taking a linear combination of the results of numerical phase detection using multiple integer periods. We also established a method to unambiguously determine the phase rotation angle in AC transport measurements using a frequency range of tens of kilohertz.

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We report on the development of a capacitance measuring system that allows measurements of capacitance in pulsed magnetic fields up to 61 T. By using this system, magnetic-field responses of various physical quantities, such as magnetostriction, magnetic-field-induced change in complex dielectric constant, and magneto-caloric effect, can be investigated in pulsed-magnetic-field conditions. Here, we examine the validity of our system for investigations of these magnetic-field-induced phenomena in pulse magnets.

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Article Synopsis
  • This study tracked the movements of 20 wild Japanese eels and 12 cultured eels in a lagoon in northeastern Japan using acoustic telemetry to understand their habitat use in different environments.
  • 40% of wild eels remained near their release point for overwintering, while others showed varying degrees of movement between the lagoon and surrounding areas, which demonstrated behavioral flexibility.
  • The study revealed key differences between wild and cultured eels, such as longer residency times and specific seasonal movements for wild eels, highlighting the importance of habitat connectivity among rivers, estuaries, and marine environments.
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The Mekong giant catfish is one of the largest freshwater fish, measuring up to 3 m in total length. This study was designed to determine the feeding habits of to better understand how the fish achieve their large body size. We compared the relationship between gut length (GL) and total length (TL) among related species in superfamily Bagroidea, order Siluriformes ( and ) in the Kaeng Krachan reservoir, Thailand.

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