A novel Fermi-level managed barrier diode has been developed for achieving broadband and low-noise terahertz-wave detection. The fabricated quasi-optical module detected signals at frequencies from ...200 GHz to 1 THz. The typical voltage sensitivity was 1020 V/W, and the current sensitivity for a 50 Ω load was 4.5 A/W at 300 GHz for a zero-biased condition. Square-law detection with good linearity was demonstrated at 300 GHz with an output current density exceeding 103 A/cm2.
Patient and staff cohorting is part of a bundle approach in the response to multi-drug-resistant organisms, but its effectiveness is not fully clarified. This study compared the risks of acquiring ...vancomycin-resistant Enterococcus faecium (VREfm) at a hospital during a VREfm outbreak based on contact characteristics in order to better understand the effectiveness of cohorting.
Exposure came from contact with patients with VREfm (infectors), including existing patients with VREfm and patients who acquired VREfm during the study period. Contact was defined as length of contact time, degree of sharing space, and care by the same nurses as those caring for infectors between January and March 2018. The outcome was VREfm acquisition as determined through monthly stool or rectal screening cultures. Incidence rates were calculated based on contact patterns, and incidence rate ratios (IRRs) were compared.
Among 272 inpatients (4038 patient-days), 43 patients acquired VREfm with the same or similar pulsotype. Incidence rates were 8.45 per 1000 patient-days when susceptible inpatients were on the same ward as an infector but cared for by different nurses (reference), 16.96 when susceptible inpatients were on the same ward as an infector and cared for by the same nurses IRR 2.01, 95% confidence interval (CI) 0.62–10.28, and 52.91 when susceptible inpatients shared a room with an infector (IRR 6.26, 95% CI 1.61–35.40).
Compared with susceptible inpatients in a different room from infectors and not being cared for by the same nurses, the risk of VREfm acquisition could be six times higher for susceptible inpatients who are in the same room as infectors, and could be double for susceptible inpatients cared for by the same nurses as infectors.
Exhumation of plutonic systems is driven by a range of mechanisms including isostatic, tectonic, and erosional processes. Variable rates of plutonic exhumation in active subduction systems may be ...driven by idiosyncrasies of regional geology or by first‐order tectonic features. We report new age, isotope, and low‐temperature thermochronology constraints of granitoids from the Hida Mountains of central Japan that constrain the highest rates and magnitude of plutonic rock exhumation within the Japan and one of the highest worldwide. This extreme exhumation is centered on the apex of a lithospheric scale anticlinorium associated with the subduction of the Izu‐Bonin oceanic arc. The spatial and temporal relationship between the exhumation of these Pleistocene plutons and the subducting/accreting Izu‐Bonin oceanic arc links the plate‐scale geodynamics and regional exhumation patterns. Identifying thermochronological anomalies within magmatic arcs provides an opportunity to identify ancient asperities previously subducted and responsible for rapid exhumation rates within ancient subduction systems.
Plain Language Summary
Plutonic rocks reach the surface through a variety of geological processes. Generally, this is driven by active tectonic and erosive forces. We provide high‐precision geochronological constraint on the youngest exposed subduction zone plutons found in the Hida Mountains of Japan that are 818.5 ± 9.6 thousand years old. Regionally, the Hida Mountains is identified as a thermochronological “hot spot” where the rocks in the region came to the surface very rapidly within the past ~300,000 years. The exhumation of these plutons was driven by the subduction of the Izu‐Bonin oceanic arc.
Key Points
Timing of crystallization and exhumation of the youngest exposed plutons is constrained with high precision analytical techniques
One of the highest exhumation rates for plutonic rocks worldwide is reported
Exhumation of Pleistocene granitoid plutons is driven by subducting Izu‐Bonin oceanic arc
Hydrodynamic instabilities often cause spatio-temporal pattern formations and transitions between them. We investigate a model experimental system, a density oscillator, where the bifurcation from a ...resting state to an oscillatory state is triggered by the increase in the density difference of the two fluids. Our results show that the oscillation amplitude increases from zero and the period decreases above a critical density difference. The detailed data close to the bifurcation point provide a critical exponent consistent with the supercritical Hopf bifurcation.
Increasing evidence suggests that distinct inflammatory cytokines convert forkhead box protein P3 (FOXP3+) regulatory T-cells (Tregs) into IL-17-producing cells (Th17 cells) in vitro. However, this ...functional plasticity has not been examined in the pathogenesis of periodontal disease. In this study, we analyzed the IL-17A+FOXP3+ cells present in periodontitis lesions to determine the association between Treg conversion and the pathogenesis of periodontitis. The immunohistochemical analysis of gingival tissues demonstrated that the numbers of Th17 cells (IL-17A+FOXP3−) and Tregs (IL-17A−FOXP3+) were greater in periodontitis lesions than in gingivitis lesions. We further identified a small number of IL-17A+FOXP3+ cells in periodontitis lesions but not in gingivitis lesions. The flow cytometry analysis of CD4+ T-cell lines established from gingival tissues and the peripheral blood of periodontitis patients showed that the proportion of Tregs was reduced and the proportion of IL-17A+FOXP3+ cells among all FOXP3+ cells was elevated in gingival tissue T-cell lines relative to the proportions in peripheral blood T-cell lines. Our findings indicate that Treg-Th17 conversion may occur in periodontitis lesions. Further studies addressing the role of Treg conversion during inflammatory responses against periodontopathic bacteria are needed.
Acute cholecystitis can occur both inside and outside hospital settings. However, little is known about the clinical characteristics of hospital-acquired cholecystitis (HAC).
To investigate the ...clinical characteristics of HAC in a tertiary academic hospital.
This retrospective cohort study included hospitalized patients who were found to have gallstones without cholecystitis or cholangitis on admission between January 2018 and December 2021. Multi-variate logistic regression analysis was used to make comparisons between patients with and without HAC.
In total, 890 patients met the inclusion criteria and were evaluated in this study. Forty-one patients (4.6%) developed HAC during the study period. Multi-variate logistic regression analysis showed that a history of cholecystitis or cholangitis, fasting for ≥1 day, and gallstones in the gallbladder neck were independently associated with increased risk of HAC. HAC occurred most frequently after several weeks of admission, and only four patients (9.8%) had bacteraemia.
HAC was relatively common among hospitalized patients. Physicians should be aware of the possibility of HAC in symptomatic hospitalized patients with certain risk factors.
Several global databases of eruption properties have been developed in recent years, which contain eruption age, eruption magnitude, eruption style, and volcanic explosivity index. However, their ...examinations of the relationships between eruption and magmatic properties remain qualitative. To explore such relationships, we sampled and petrologically analyzed the eruptive products and have constructed a database of magmatic properties of erupted magmas at Japanese arc volcanoes during the last one hundred thousand years. The 43 erupted magmas were characterized not only by bulk SiO2 content, but also by preeruptive melt SiO2 (inferred from groundmass SiO2 content) and phenocryst contents, which are the second most straightforward proxies of physical and thermodynamic properties of preeruptive magmas. Sample data were collected through a unified procedure using chemical and image analyses and mass balance calculations to obtain groundmass compositions and phenocryst contents. We examined the relationships between magmatic properties and eruption magnitude, M, as the most representative eruption property. Our database includes explosive eruptions of M 3 to 8. By incorporating available literature data for 17 eruptions, we examined 60 eruptions in total. This study distinguished magmas from the bulk composition (e.g., basaltic, andesitic, dacitic and rhyolitic magmas) or melt composition (e.g., basaltic, andesitic, dacitic and rhyolitic melt-bearing magmas). Our results show that the maximum eruption magnitude gradually increases with increasing bulk SiO2 content. The maximum eruption magnitude shows a sharp increase around the compositional boundary between dacitic and rhyolitic melt-bearing magmas. For the eruptions of rhyolitic melt-bearing magmas, the maximum eruption magnitude decreases with increasing phenocryst content. The largest magnitude eruptions (M 8) were of rhyolitic melt-bearing, phenocryst-poor magmas. We compared our data for Japanese arc volcanoes with data for global volcanoes. Despite their different tectonic settings, most eruptions globally are consistent with the pattern observed for eruptions at Japanese arc volcanoes. Notable deviations are supereruptions (M > 7) of monotonous intermediate magmas that occurred more than a million years ago. Although more examination is needed, especially for smaller and effusive eruptions, the observed relationships suggest that melt SiO2 and phenocryst contents are related to maximum eruption magnitude, and should be fundamental components to characterize volcanoes and eruptions in future databases studies.
•Database of properties of erupted magmas in Japan during the last 100 ky•Characterization of magmas by preeruptive melt SiO2 and phenocryst contents•Relationships between magmatic properties and eruption magnitude•Maximum eruption magnitude increases sharply for rhyolitic melt-bearing magmas.•Maximum eruption magnitude decreases gradually with increasing phenocryst content.
The flow characteristics of circulating water in a proton exchange membrane (PEM) electrolyzer were experimentally evaluated using a small cell and two-phase flow theory. Results revealed that when a ...two-phase flow of circulating water at the anode is either slug or annular, then mass transport of the water for the anode reaction is degraded, and that the concentration overvoltage increases at higher current density compared to that when the flow is bubbly. In a serpentine-dual flow field, when both phases of the two-phase flow are assumed laminar, then the increase in pressure drop caused by the increase in gas production can be explained relatively well using the Lockhart–Martinelli method with the Chisholm parameter. The optimal flow rate of circulating water was also discussed based on mass balance analysis.
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