University of the Ryukyus

Quasi-steady non-charring ablation in a semi-infinite solid with linearly temperature-dependent thermal properties is solved by two kinds of perturbation methods, where the surface temperature and recession rate are constants. One is the conventional perturbation method (CPM) and the other is the modified perturbation method (MPM), where the perturbation parameters are α (thermal conductivity parameter) and γ (specific heat parameter). The solutions by the CPM, MPM, and the finite difference method (FDM) are compared. The effects of α and γ upon the dimensionless temperature are investigated. It is found that the MPM solution is more accurate than the CPM solution and the MPM extends the applicable range of the perturbation parameters, α and γ, compared with the CPM. The solutions by three kinds of calculation methods (FDM, CPM and MPM) are compared with the measured results. Application of these solutions to Teflon material is discussed.

Objective. Effective rehabilitation for upper limb paralysis in patients with intracerebral hemorrhage mediated by hemiplegia has not yet been established. We evaluated the effectiveness of upper limb functional training using a wearable-type exoskeleton driven by bio-electric signals using upper limb motor function scores and tractography of the corticospinal tract (CST). Approach. Nine patients with putamen and seven with thalamus hemorrhage were trained using the hybrid assistive limb (HAL) of the wearable exoskeleton. Among the participants, 12 individuals were patients with severe hemiplegic, indicated by a Fugl–Meyer assessment (FMA) score of 10. We also investigated the relationship between improvement in upper limb function and changes in mean diffusivity, axial diffusivity, radial diffusivity (RD), or fractional anisotropy (FA) in the CST. Main results. Following HAL training, upper limb function scores increased in all patients. We observed a clinically significant improvement in nine patients, with a mean effect size of 26 ± 12.7. HAL training was effective in improving upper limb function in patients with an FA ratio (the affected/unaffected side) ⩾0.86 in the CST. Patients with clinically significant improvements had a mean 16 ± 15% increase in FA ratio in the CST. Patients with greater improvement in upper-limb function tended to have lower RD values in the CST, and the effect size of the RD value and FMA was demonstrated to be negatively correlated (rs = −0.54). An increase in FA ratio and a decrease in RD values in the CST of the cerebral peduncle are significant findings that suggest improvements in upper limb function. Significance. These findings highlight the effectiveness of HAL training in improving upper-limb dysfunction in patients with subacute cerebral hemorrhage. Improvement of upper limb function by assistive actuation with the wearable exoskeleton based on bio-electric signals may be caused by the promotion of the restoration of white matter integrity of the CST.

Individuals with metabolic-associated steatotic liver disease (MASLD) have a worse prognosis compared to patients without steatosis, and its prevalence is increasing. However, detailed risk factors based on obesity and sex remain unclear. We aimed to investigate the impact of cardiometabolic risk factors (CMRFs) on the risk of MASLD in individuals without pre-existing SLD. SLD was diagnosed by ultrasonography. Non-SLD individuals were followed 65,657 person-years. Incidence rates of MASLD were assessed by Kaplan–Meier analysis. Furthermore, independent factors associated with the development of MASLD were identified using Cox regression analysis, stratified by four groups: obese men, non-obese men, obese women, and non-obese women. The overall incidence rate of MASLD was 39.3/1,000 person-years. The cumulative incidence was highest in obese men, followed by obese women, non-obese men, and non-obese women. Two or more CMRFs increased the risk of MASLD in all groups. Low HDL cholesterol level was the strongest independent risk factor in both obese and non-obese women and hypertriglyceridemia for both obese and non-obese men. The impact of these CMRFs was stronger in non-obese individuals. (HR [95% CI]: women non-obese 1.9 [1.5–2.4], obese 1.4 [1.1–1.8]; men non-obese 2.3 [1.9–2.9], obese 1.5 [1.2–2.0]). Multiple CMRFs are important to MASLD development, regardless of sex and obesity. In this Japanese cohort, low HDL cholesterol in women and hypertriglyceridemia in men were the most significant risk factors, especially among the non-obese group. These findings suggest that sex-specific CMRFs may play a role in the development of MASLD.

In nature, organisms are exposed to scents and tastes composed of multiple rather than single chemicals. The ability to sense and correctly identify different chemicals within these complex mixtures is essential for optimized behavior. However, when minor variations in chemical structure do not significantly impact the organisms, a generalized response to similar chemicals without discrimination might be more adaptive. In this study, we investigated the ability of ants to discriminate among methyl-branched alkanes. Ants recognize each other using cuticular hydrocarbons (CHCs), typically composed of a mixture of n-alkanes, n-alkenes, and methyl-branched alkanes. Tetramorium tsushimae ants have been shown to use the methylalkane fraction of CHCs to identify their mutualistic partners. We measured the behavioral responses of ant workers to dummies coated with various hydrocarbons, after presenting them with dummies treated with methylalkanes and a sucrose solution as a reward. The results showed that ants previously exposed to 2-methyltetracosane (2-MeC24) decreased their aggression not only toward 2-MeC24 but also toward 2-MeC26, despite the difference in the chain lengths. Conversely, ants exposed to 13-MeC27 maintained high levels of aggression toward 5-MeC27, which has the methyl branch in a different position. These findings suggest that T. tsushimae ants can differentiate between methylalkanes with different methyl branch positions, but are less able to discriminate between those with the same methyl branch position but different chain lengths.

Lipid‐based formulation of antifungal small drugs is used to mitigate drug toxicity while retaining effective antifungal activity. Our previous work demonstrated a method to enhance the antifungal properties of a chitin‐binding domain (LysM) and catalytic domain (CatD) of antifungal chitinase by microbial transglutaminase (MTG)‐mediated palmitoylation. Herein, we studied the effect of artificial cholesterylation of LysM and CatD, both of which were site‐specifically modified using an MTG‐catalyzed crosslinking. This produced protein–lipid conjugates (LysM‐cholesteryl [Chol] or ‐palmitoyl [Pal] and CatD‐Chol or ‐Pal). Although lipidation of these chitinase domains enhanced the antifungal activity against Trichoderma viride, palmitoylated proteins (LysM‐Pal and CatD‐Pal) showed stronger antifungal effects than cholesterylated proteins (LysM‐Chol and CatD‐Chol) both in the absence and presence of amphotericin B. Further characterization with lipidated LysM‐fused green fluorescent protein (LysM‐muGFP‐Pal and ‐Chol) showed that the cholesterylation of proteins promoted distribution to dextran‐rich phase in an aqueous two‐phase system consisting of polyethylene glycol and dextran. Fluorescence microscopic analyses of the phase‐separated giant unilamellar vesicles revealed distinct anchoring behavior between LysM‐muGFP‐Pal and ‐Chol to lipid membranes, which was possibly correlated with aggregate formation. These results highlight that the chemical properties of the lipid moiety are crucial to achieve effective enhancement of antifungal activity through artificial lipidation.

The genus Xystodesmus Cook, 1895 (most closely related to Riukiaria Attems, 1938) is retained as a taxon of xystodesmine millipedes with a relatively small body length (25–35 mm), male gonopods more complicated than just a forceps-like conformation, and with live colouration of grey-brown tergites with red, orange, or yellow paranotal spots. Seven new species of the genus (Xystodesmus fasciatussp. nov., X. keramaesp. nov., X. kumamotoensissp. nov., X. kumeensissp. nov., X. parvussp. nov., X. rebekaesp. nov., X. sesokoensissp. nov.) are described from the islands of Kyushu, Okinawa-jima, Kume-jima, Okinoerabu-jima, Aka-jima, Amami-O-shima, and Sesoko-jima, southwestern Japan. Koreoaria Verhoeff, 1937, syn. nov. is synonymised with Xystodesmus Cook, 1895, so X. pallidus (Verhoeff, 1937), comb. nov. (ex Koreoaria pallida), and X. amoenus (Takakuwa, 1942), comb. nov. (ex K. amoena) are established. Furthermore, X. variatus (Pocock, 1895), comb. nov. (ex Fontaria variata), and X. saltuosus (Haga, 1968), comb. nov. (ex Rhysodesmus saltuosus) are re-evaluated and redescribed, based on re-examination of types and of freshly collected material (X. variatus only). All new species, as well as X. martensii (Peters, 1864), X. nikkoensis (Chamberlin & Wang, 1953), and X. variatus are illustrated with colour habitus photographs taken of live specimens, to facilitate field identification.

Rosai–Dorfman–Destombes disease (RDD) is a rare form of histiocytosis, characterized by the accumulation of S100 protein-positive and CD1a-negative histiocytes with emperipolesis. Recently, oncogenic mutations in mitogen-activated protein kinase pathway genes were reported in nearly half of RDD patients. We conducted a nationwide retrospective survey of childhood RDD in Japan. We found nine patients (five boys and four girls) with a median age at diagnosis of 8 years and 3 months (range, 9 months to 15 years 5 months). Two patients had nodal lesions only, three had extra-nodal lesions only, and four had both. PD-L1 was expressed in all cases. Two were resolved without treatment. Three were treated with prednisolone, one with surgery and radiation, and three with chemotherapy. Two were complicated by glomerulonephritis. Somatic pathogenic mutations in the kinase pathway genes were found in five of the six patients analyzed (three in MAP2K1, one in KRAS, and one in TSC1). Two chemotherapy-resistant patients with MAP2K1 mutations responded to trametinib. Within a median follow-up of 4 years and 9 months, two died of disease. Most children with RDD carry mutations in the kinase pathway genes. Mutation analysis is suggested for patients with refractory disease.

The deep-sea cardinalfish Epigonus glossodontus Gon, 1985, previously known only from the Hawaiian Islands, was observed using remotely operated vehicles (ROVs) on steep seafloors surrounding Kitadaito and Minamidaito islands, both being oceanic islands belonging to the Daito Islands, Japan in the northwestern Pacific. A total of 44 hours of ROV observations found sparse populations, each of several individuals, around or within small caves, fissures, and recesses, specifically at depths of 340–588 m within the surveyed depth of 284–1009 m. Seven individuals (36.0–114.8 mm standard length) were successfully collected during the ROV observations around the Daito Islands. A subsequent record of the species (97.5 mm standard length) from the Kyushu-Palau Ridge indicated that the species is widely distributed. A glossy bluish-green body color with black-margined scales was revealed by the field observations, the glossy color fading immediately after death.

The last glacial period, between around 115 and 12 thousand years before present, exhibited strong millennial-scale climate variability. This includes abrupt transitions between cold and warm climates, known as Dansgaard–Oeschger (D–O) cycles. D–O cycles have been linked to switches in dynamical regimes of the Atlantic Overturning Meridional Circulation (AMOC), but the exact mechanisms behind abrupt climate changes and AMOC regime shifts remain poorly understood. This paper introduces the convection–advection oscillator mechanism to explain the millennial-scale oscillations observed in a set of HadCM3 general circulation model simulations forced with snapshots of deglacial meltwater history. The oscillator can be separated into two components acting on different time scales. The fast convection component responds to changes in vertical stratification in the North Atlantic by activating or deactivating deep water formation sites. The slow advection component regulates the accumulation and depletion of salinity in the North Atlantic. This oscillator mechanism is triggered under specific background conditions and freshwater release patterns. The freshwater perturbation causes an instability that triggers a global salt reorganisation, modifying the North Atlantic stratification. For a given forcing pattern, the system oscillates if the salt transport can lead to an alternating reactivation and deactivation of the AMOC. Otherwise, the climate settles in a warm or cold steady state. This mechanism expands existing theories of millennial-scale variability and provides a general framework for understanding abrupt climate change in general circulation models.

Aim To assess the efficacy of continuous dasatinib in improving outcomes for adult patients with BCR::ABL1 ALL. Methods The prospective, multicenter ALL/MRD2014 trial introduced a modified protocol compared to the MRD2008 trial, incorporating continuous dasatinib use and reduced chemotherapy intensity. Results Among the 164 adult ALL patients enrolled (2014–2019), 61 were Philadelphia‐positive (Ph+) (median age 50 years; 38 males, 23 females). Post‐induction, 96.7% achieved complete remission (CR). The 3‐year event‐free survival (EFS) and overall survival (OS) were 51% and 76%, respectively. Patients undergoing allo‐HSCT in CR1 had improved outcomes, with a 3‐year EFS of 64% and OS of 87%. MRD‐negative patients before transplantation exhibited superior survival (EFS: 71% vs. 29%; OS: 94% vs. 57%). Comparison with the MRD2008 trial revealed similar outcomes, with the MRD2014 trial achieving a 3‐year EFS of 51% and OS of 76% vs. 52% and 84% in MRD2008. Although not statistically significant, the MRD2014 trial showed trends of increased relapse (CIR: 39% vs. 26%, p = 0.305) and reduced non‐relapse mortality (NRM: 10% vs. 21%, p = 0.181). Conclusion The ALL/MRD2014 trial underscores the importance of MRD status and allo‐HSCT in Ph+ ALL. Continuous dasatinib‐based regimens offer favorable outcomes in MRD‐negative patients. Trial Registration This study was registered with the UMIN Clinical Trials Registry (UMIN‐CTR), number UMIN000012382

This study aimed to evaluate the impact of a health education intervention on women's cervical cancer screening uptake. It was conducted using data from the collaborative project by the Cambodian Society of Gynecology and Obstetrics and the Japan Society of Obstetrics and Gynecology to improve cervical cancer services in Cambodia. A prospective observational study was conducted from August 2022 to May 2023, involving 1,538 female teachers from 80 public primary schools in Phnom Penh, Cambodia. A total of 815 participants (intervention group [n = 355] and control group [n = 460]) were eligible for analysis. The intervention group received a tailored health education program and an invitation to register for free cervical cancer screening, while the control group only received the invitation to screening. The intervention group demonstrated a significantly higher screening registration (32.1% vs. 18.8%, p < 0.001) and uptake (24.1% vs. 12.7%, p < 0.001) than the control group. When comparing changes in knowledge and attitude between baseline and endline assessments, the intervention group showed a notable improvement in knowledge regarding the causes, symptoms, prevention, and benefits of early detection of cervical cancer. For instance, the proportion of women who recognized human papillomavirus as the cause of cervical cancer significantly increased in the intervention group (baseline: 23.7%, endline: 57.5%, p < 0.001), while no significant change was observed in the control group (baseline: 24.4%, endline: 29.1%, p = 0.101). In conclusion, the health education program effectively increased cervical cancer screening uptake, knowledge and attitude on cervical cancer. Further improvements in screening uptake may require educational interventions that influence individual health behaviors and systematic encouragement for screening participation.

Coral reefs are essential for biodiversity and ecosystem services, yet they face threats like bleaching and reduced resilience due to rising seawater temperatures and land-based pollution. This study examined phosphate accumulation in calcareous sediments and its relationship with coral populations in Sekisei Lagoon, Okinawa Islands, Japan. Sediment samples from 117 sites were analyzed for exchangeable phosphate in seawater (EPS), which could be released from the calcareous sediments. The EPS levels were negatively correlated with coral densities for adults (Pocillopora, Acropora, Galaxea, Favia, Favites, Goniastrea, and Cyphastrea) and juveniles (Pocillopora, Montipora, Acropora, Galaxea, Favia, Favites, and Goniastrea). No significant correlation was found for Porites or Millepora. The EPS levels were positively correlated with coral bleaching and the abundance of Sargassaceae algae. High coastal EPS levels suggest main pollution sources from livestock and shrimp farming. The threshold above which EPS impacts coral bleaching and density was estimated at 0.3–0.7 µg/g, providing insights for coral reef conservation.