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Dietary Diversity of the Amami Rabbit Endemic to Insular Evergreen Forests
Get PDFThe Amami rabbit (Pentalagus furnessi), endemic to the Amami-Oshima and Tokunoshima Islands, is an endangered species that faces habitat disturbance. This study used fecal DNA metabarcoding to analyze the dietary preferences of Amami rabbits. Fecal samples from six rabbits were collected and analyzed for plant DNA. The results revealed the presence of 85 operational taxonomic units (OTUs) representing different plant species, with individual rabbits consuming 17–38 plant species. The dietary composition varied significantly among individuals, with a notable preference for ferns in some cases. Diet diversity, assessed using Simpson's Diversity Index, ranged from 0.328 to 0.889. This study highlights the importance of a diverse plant diet for Amami rabbits and underscores the need for habitat preservation to ensure a stable food supply. Conservation efforts must focus on maintaining a unique subtropical moist forest ecosystem and mitigating human-wildlife conflicts to promote sustainable coexistence.Zoological Studies, 64, art. no. 12; 2025journal articl
Reverse osmosis membrane surface modification with hydrophilic amines for enhanced N-nitrosamine separation and antifouling performance
No full textReverse osmosis (RO) membranes used for potable water reuse have limitations in rejecting small constituents such as N-nitrosamines. This study aimed to modify a commercial RO membrane (ESPA2) with hydrophilic methyl-polyethylene glycol-amine (methyl-PEG-amine) to enhance its separation performance and fouling resistance. Modification with a large methyl-PEG-amine, with an optimal minimum projection area (MPA) of 42 Å2, increased the N-nitrosodimethylamine (NDMA) rejection from 47 % to 60 %. This enhanced rejection was comparable to that of the hydrophobic amine modifier (i.e., dodecylamine), but with the advantage of 25 % higher water permeance. This could be attributed to effective immobilization of hydrophilic amine within the membrane through electrostatic attraction and strong hydrogen bonding networks with the membrane, facilitating size exclusion for N-nitrosamines. An additional key benefit of hydrophilic amine modification is enhanced membrane fouling resistance. The modified membrane exhibited an 18 % smaller drop in permeate flux compared to the pristine membrane when treating synthetic organic solution (a mixture of humic acid, sodium alginate, and bovine serum albumin). This study highlights the potential of non-toxic methyl-PEG-amine as an RO membrane modifier for the simultaneous enhancement of antifouling properties and N-nitrosamine rejection, with minimal compromise to water permeance.Separation and Purification Technology, 378, art. no. 134751; 2025journal articl
地域・保護者との協働で子どもを育てる学校組織マネジメント－小学校区の取組に焦点をあてて－
Get PDF長崎大学教育学部教育実践研究紀要, 24, pp.43-52; 2025departmental bulletin pape
身体運動の発展史にみる体育授業教材の観点―表現運動系の領域を中心に―
Get PDF長崎大学教育学部教育実践研究紀要, 24, pp.97-106; 2025departmental bulletin pape
災害公営住宅のコモンスペースと団地内活動がコミュニティ形成に与える影響 ―熊本地震の災害公営住宅を通して―
Get PDFThis study examines resident interactions and the role of community spaces in disaster housing seven years after the Kumamoto Earthquake. Disaster-related solitary deaths, particularly among elderly survivors in permanent housing, remain a critical issue. With limited support systems in place, social interactions are crucial for reducing isolation and preventing solitary deaths.The survey targeted 15 housing complexes in Kumamoto Prefecture, revealing that 67% of residents were elderly, mostly living alone. Many residents reported having no acquaintances when they moved in. While 33.8% of the complexes had community centers and 45.5% had plazas, the usage rates of these spaces were low. In community centers, 32% of residents reported never using them, though over 60% deemed them necessary, particularly for events. Housing complexes with integrated community centers had more frequent interactions compared to those with detached facilities.Similarly, while 53% of residents never used the plazas, over 60% considered them necessary. Plazas located along pedestrian routes fostered more interactions than those in isolated areas. Residents using community centers tended to have stronger social connections, especially when these centers were frequently used and well-integrated into the housing layout. Additionally, complexes with leaders elected voluntarily had higher levels of interaction compared to those with leaders chosen by a rotation system.The study underscores the importance of well-designed community spaces and regular events in facilitating interactions and preventing isolation. Future observational research will focus on particularly active complexes to further explore successful interaction strategies.長崎大学大学院工学研究科研究報告, 55(104), pp.59-64; 2025departmental bulletin pape
Living Donor Liver Transplantation with Small Left Lobe Grafts: Prospective Validation of Utility of Splenectomy in Selected Recipients
Get PDFBACKGROUND: We previously reported that the Model for End-stage Liver Disease (MELD) score and donor age are risk factors for small-for-size syndrome in adult living donor liver transplantation (LDLT) involving small grafts. Since April 2021, we have performed splenectomy as a portal inflow modulation in LDLT using small grafts according to the presence of risk factors. In this study, we evaluated the validity of our splenectomy strategies for optimizing graft outcomes. MATERIAL AND METHODS: We retrospectively reviewed patients who underwent primary LDLT using left lobe grafts with the middle hepatic vein from January 2005 to January 2024 at our institution. We also compared the graft outcomes between recipients who underwent LDLT beginning in April 2021 (current policy group) and those who underwent LDLT in the era when splenectomy as portal modulation was not indicated (previous policy group). RESULTS: In total, 173 consecutive LDLTs (current policy group: n=15) involving left lobe grafts were analyzed. Splenectomy was performed in 9 of 15 (60.0%) patients in the current policy group. All 15 patients in the current policy group remained alive for a median follow-up of 20.5 months. The rate of early allograft dysfunction was significantly lower, and the rate of small-for-size syndrome tended to be lower in the current policy group than in the previous policy group (13.3% vs 39.2%, P=0.047 and 20.0% vs 36.1%, P=0.211, respectively). CONCLUSIONS: LDLT with splenectomy for high-risk patients may expand the availability of small left lobe grafts and optimize graft outcomes.Annals of transplantation, 30, art. no. e946374; 2025journal articl
Enhancing corrosion resistance of AISI 4130 steel through optimized HVOF tungsten carbide coatings
Get PDFIn the petroleum and petrochemical industries, equipment integrity is jeopardized by aggressive environments promoting corrosion. This study investigates the impact of high-velocity oxygen fuel (HVOF) thermal spray coating parameters on the quality and corrosion resistance of tungsten carbide coatings applied to AISI 4130 steel. Critical parameters such as powder feed rate (60–72 g/min) and spray intensity (6.7–7.2 bar) were optimized for treated samples S3 and S5. Scanning electron microscopy (SEM) images were analyzed to assess coating thickness and quality. Mechanical properties were evaluated using Vickers hardness tests, revealing a substantial increase in hardness from 225 Vickers for the uncoated sample (S0) to 2010 and 2060 Vickers for coated samples S3 and S5, respectively, and in sample S5 compared to S3, the value increased by 2.46% (∗p < 0.05). Corrosion resistance was assessed through Tafel and Nyquist tests, indicating that the HVOF coatings exhibited superior corrosion resistance compared to the control sample. Notably, sample S5 demonstrated lower current density and a more positive corrosion potential than S3, suggesting enhanced protective performance against corrosive ions. The Nyquist plot analysis further confirmed that sample S5 exhibited a higher corrosion resistance due to its uniform distribution of tungsten carbide and reduced porosity. Ultimately, the HVOF coating with a spray intensity of 7.2 bar and a powder feed rate of 72 g/min (sample S5) was identified as the optimal configuration for maximizing corrosion resistance.Results in Surfaces and Interfaces, 18, art. no. 100450; 2025journal articl
Clinicopathological and molecular characteristics of papillary thyroid carcinoma in adolescent and young adult patients
Get PDFAdolescent and young adult (AYA, 15–39 years old) patients with papillary thyroid carcinoma (PTC) experience significant psychological distress and place great importance on obtaining information regarding the disease; however, their demands remain unmet. We aimed to investigate clinicopathological and molecular features of PTC in AYA patients and compare them to those of PTC in older patients (≥40 years). This retrospective study enrolled 1,677 patients diagnosed with PTC from January 2018 to December 2022, with 400 AYA patients and 1,277 older adults. At the time of diagnosis, AYA patients with PTC had higher rates of presentation in females, larger tumor size (>2.0 cm), lymphatic vessel invasion, chronic thyroiditis, clinical lymph node metastasis, and pathologic lymph node metastasis, but lower rates of multifocality and extrathyroidal extension compared with PTC in older adults. The two groups had no significant differences regarding surgical method and distant metastasis. The prevalences of BRAF p.V600E and TERT promoter mutations of PTC were significantly lower in AYA patients (69.1% vs. 82.6% and 1.3% vs. 18.8%, respectively; both p < 0.001). In conclusion, PTC in AYA patients differed from PTC in older patients. Particularly, BRAF p.V600E and TERT promoter mutations in AYA with PTC were less frequently observed than in older adults.Endocrine Journal, 72(2), pp.221-227; 2025journal articl
Comparison of clinical and virological features in pediatric and adult dengue cases at Insein General Hospital during Myanmar’s 2022 dengue season
Get PDFBackground: Myanmar is one of the countries in Southeast Asia where serious dengue outbreaks occur and Yangon is among the regions with the highest number of cases in the country. Many infections including dengue are common in Yangon during the rainy season, and co-infections may also occur. Adults are more likely than children to experience co-infections of dengue and other diseases. Although pediatric dengue has been studied in Yangon for decades, research on adult dengue is scant. Therefore, this study compared the clinical and virological characteristics of pediatric and adult dengue cases in Yangon. Methods: This cross-sectional study was conducted at Insein General Hospital in Yangon, Myanmar, from June to September 2022. We recruited 221 suspected dengue patients (134 children and 87 adults), with or without other diseases, and tested their dengue serological markers using a serological method and their dengue virus (DENV) serotypes using conventional RT-PCR. Chi-squared and Fisher’s exact tests were conducted to assess signifcance. Results: The dengue non-structural protein-1 antigen (NS1Ag) positivity was 37% in children and 32% in adults. DENV serotypes were identifed in 80% of NS1Ag-positive patients. Among NS1Ag-positive cases, the DENV-1 serotype predominated (67%), followed by DENV-2 (17%), DENV-3 (9%), DENV-4 (5%), and mixed DENV-1 and DENV-2 (2%) serotypes. Shock was observed in 14% of children and 3% of adults. Anti-dengue IgG antibody positivity was positively correlated with dengue shock. Three pediatric dengue cases (6%) also had other infections including bronchiolitis, ear infection, and diarrhea. Seven adult dengue cases (25%) also had other diseases including advanced HIV infection, severe pneumonia, tonsillitis, thyroid disease, cholecystitis, drug poisoning, and thalassemia. Conclusion: The serotype distribution and clinical presentations of pediatric and adult dengue cases were not signifcantly diferent, but adults were more likely to have dengue together with other diseases than children. This study provides information for the better management of febrile children and adults in hospital settings and provides a foundation for nationwide epidemiological studies on dengue serotypes and modifcations of the national guidelines for dengue management in Myanmar.Tropical Medicine and Health, 53(1), art. no. 13; 2025journal articl