101 research outputs found

    Wide-band frequency modulation of a terahertz intrinsic Josephson junction emitter of a cuprate superconductor

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    Communication using terahertz (∼10¹²Hz) electromagnetic waves is critical for developing sixth-generation wireless network infrastructures. Conflictions between stable radiation and frequency modulation of terahertz sources impede the superposing of transmitting signals on carrier waves. The Josephson junctions included in a cuprate superconductor radiate terahertz waves with frequencies proportional to the bias voltages. Thus, the modulation of the bias voltage leads to the modulation of the Josephson plasma emission (JPE) frequency. This study aims to demonstrate the generation of frequency-modulated (FM) terahertz continuous waves from Josephson junctions. A FM bandwidth of up to 40 GHz was achieved when 3 GHz sinusoidal waves were superimposed on 840–890 GHz carrier waves radiated by a JPE. The results verify that the instantaneous JPE frequency follows the gigahertz-modulated bias voltage. The wide-band FM terahertz generation by a monolithic device shows a sharp contrast to the mode-lock frequency comb constructed using highly sophisticated optics on a bench. A further increase of the modulation amplitude facilitates up- or downconversion of frequencies over more than one octave. The obtained FM bandwidth exhibited an improvement of two orders of magnitude in the demodulation signal-to-noise ratio compared with the amplitude-modulated waves. The demonstrated FM JPE stimulates further research on terahertz communication technology and metrology using superconducting devices

    PABPC1 mediates degradation of C9orf72-FTLD/ALS GGGGCC repeat RNA

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    Uozumi R., Mori K., Gotoh S., et al. PABPC1 mediates degradation of C9orf72-FTLD/ALS GGGGCC repeat RNA. iScience 27, 109303 (2024); https://doi.org/10.1016/j.isci.2024.109303.GGGGCC hexanucleotide repeat expansion in C9orf72 causes frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Expanded GGGGCC repeat RNA accumulates within RNA foci and is translated into toxic dipeptide repeat proteins; thus, efficient repeat RNA degradation may alleviate diseases. hnRNPA3, one of the repeat RNA-binding proteins, has been implicated in the destabilization of repeat RNA. Using APEX2-mediated proximity biotinylation, here, we demonstrate PABPC1, a cytoplasmic poly (A)-binding protein, interacts with hnRNPA3. Knockdown of PABPC1 increased the accumulation of repeat RNA and RNA foci to the same extent as the knockdown of hnRNPA3. Proximity ligation assays indicated PABPC1-hnRNPA3 and PABPC1-RNA exosomes, a complex that degrades repeat RNA, preferentially co-localized when repeat RNA was present. Our results suggest that PABPC1 functions as a mediator of polyadenylated GGGGCC repeat RNA degradation through interactions with hnRNPA3 and RNA exosome complex

    Surface Chemistry Involved in Epitaxy of Graphene on 3C-SiC(111)/Si(111)

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    Surface chemistry involved in the epitaxy of graphene by sublimating Si atoms from the surface of epitaxial 3C-SiC(111) thin films on Si(111) has been studied. The change in the surface composition during graphene epitaxy is monitored by in situ temperature-programmed desorption spectroscopy using deuterium as a probe (D2-TPD) and complementarily by ex situ Raman and C1s core-level spectroscopies. The surface of the 3C-SiC(111)/Si(111) is Si-terminated before the graphitization, and it becomes C-terminated via the formation of C-rich (6√3 × 6√3)R30° reconstruction as the graphitization proceeds, in a similar manner as the epitaxy of graphene on Si-terminated 6H-SiC(0001) proceeds

    The bifurcation angle is associated with the progression of saccular aneurysms

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    The role of the bifurcation angle in progression of saccular intracranial aneurysms (sIAs) has been undetermined. We, therefore, assessed the association of bifurcation angles with aneurysm progression using a bifurcation-type aneurysm model in rats and anterior communicating artery aneurysms in a multicenter case-control study. Aneurysm progression was defined as growth by ≥ 1 mm or rupture during observation, and controls as progression-free for 30 days in rats and ≥ 36 months in humans. In the rat model, baseline bifurcation angles were significantly wider in progressive aneurysms than in stable ones. In the case-control study, 27 and 65 patients were enrolled in the progression and control groups. Inter-observer agreement for the presence or absence of the growth was excellent (κ coefficient, 0.82; 95% CI, 0.61-1.0). Multivariate logistic regression analysis showed that wider baseline bifurcation angles were significantly associated with subsequent progressions. The odds ratio for the progression of the second (145°-179°) or third (180°-274°) tertiles compared to the first tertile (46°-143°) were 5.5 (95% CI, 1.3-35). Besides, the bifurcation angle was positively correlated with the size of aneurysms (Spearman's rho, 0.39; P = 0.00014). The present study suggests the usefulness of the bifurcation angle for predicting the progression of sIAs

    The Efficacy of Software to Help Patients Understand Drug for Adjuvant Treatment for Breast Cancer: A Pilot Randomized Controlled Trial

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    We assessed the usefulness of ChemoCalc, a software package for calculating drug costs, in helping patients understand these costs. We randomly assigned, in a 1 : 1 ratio, 20 women who had undergone surgery for early breast cancer to a group that discussed adjuvant treatment with their physicians using the ChemoCalc software (ChemoCalc group) or a group that discussed adjuvant treatment without ChemoCalc (Usual Explanation group). The participants completed a five-grade evaluation questionnaire after these discussions. The primary endpoint was the intergroup comparison of the questionnaire scores regarding participants’ understanding of their treatment-associated drug costs. Median age was not significantly different between the ChemoCalc group and Usual Explanation group (57 vs. 50, respectively; p=0.27). Patients in the ChemoCalc group had a significantly higher perceived level of understanding of the drug cost than those in the Usual Explanation group (5 [4-5] vs. 2.5 [1-5], respectively; p=0.002). Scores related to the patients’ perception that understanding drug costs is an important part of breast cancer treatment were also higher in the ChemoCalc group than the Usual Explanation group (5 [2-5] vs. 3 [1-5], respectively; p=0.049). ChemoCalc was found to be useful for understanding drug costs

    Legionella pneumophila in Rainwater on Roads

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    During rain, transient puddles form on roads, and this water is splashed into the air by moving vehicles. To determine whether this water contains Legionella pneumophila, we collected samples from roads. We found that L. pneumophila are abundant in these puddles, especially during warm weather

    合併症を有するB型大動脈解離に対するステントグラフト内挿術における腎動脈に対する治療戦略 : 多施設共同研究

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    Background: Management of abdominal branches associated with Stanford type B aortic dissection is controversial without definite criteria for therapy after thoracic endovascular aortic repair (TEVAR). This is in part due to lack of data on natural history related to branch vessels and their relationship with the dissection flap, true lumen, and false lumen. Purpose: To investigate the natural history of abdominal branches after TEVAR for type B aortic dissection and the relationship between renal artery anatomy and renal volume as a surrogate measure of perfusion. Materials and Methods: This study included patients who underwent TEVAR for complicated type B dissection from January 2012 to March 2017 at 20 centers. Abdominal aortic branches were classified with following features: patency, branch vessel origin, and presence of extension of the aortic dissection into a branch (pattern 1, supplied by the true lumen without branch dissection; pattern 2, supplied by the true lumen with branch dissection, etc). The branch artery patterns before TEVAR were compared with those of the last follow-up CT (mean interval, 19.7 months) for spontaneous healing. Patients with one kidney supplied by pattern 1 and the other kidney by a different pattern were identified, and kidney volumes over the course were compared by using a simple linear regression model. Results: Two hundred nine patients (mean age ± standard deviation, 66 years ± 13; 165 men and 44 women; median follow-up, 18 months) were included. Four hundred fifty-nine abdominal branches at the last follow-up were evaluable. Spontaneous healing of the dissected branch occurred in 63% (64 of 102) of pattern 2 branches. Regarding the other patterns, 6.5% (six of 93) of branches achieved spontaneous healing. In 79 patients, renal volumes decreased in kidneys with pattern 2 branches with more than 50% stenosis and branches supplied by the aortic false lumen (patterns 3 and 4) compared with contralateral kidneys supplied by pattern 1 (pattern 2 vs pattern 1: −16% ± 16 vs 0.10% ± 11, P = .002; patterns 3 and 4 vs pattern 1: −13% ± 14 vs 8.5% ± 14, P = .004). Conclusion: Spontaneous healing occurs more frequently in dissected branches arising from the true lumen than in other branch patterns. Renal artery branches supplied by the aortic false lumen or a persistently dissected artery with greater than 50% stenosis are associated with significantly greater kidney volume loss.博士(医学)・乙第1461号・令和2年6月30日Copyright © 2019 by authors and RSNA. This work is licensed under the Creative Commons Attribution International License (CC BY-NC-ND 4.0). https://creativecommons.org/licenses/by-nc-nd/4.0/

    Protocol for studying the efficiency of ChemoCalc software in helping patients to understand drug treatment costs for breast cance

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    Survival of patients with breast cancer can be prolonged by treatment with drugs, particularly new molecular-targeted drugs. However, these agents can be expensive and such treatments can be “an economic burden.” In this ongoing trial, we aim to assess the usefulness of ChemoCalc, a software package for calculating drug costs, to help patients understand the financial outlays. In this multicenter, randomized controlled phase 2 trial, 106 patients with advanced breast cancer will be assigned to either the “ChemoCalc” or “Usual Explanation” group. Treatment using ChemoCalc will be discussed with patients in the ChemoCalc group, whereas standard treatments, without using ChemoCalc, will be discussed with patients in the Usual Explanation group. Subsequently, the participants will decide the treatment and complete a five-grade evaluation questionnaire; those in the Usual Explanation group will receive information about ChemoCalc. Investigators will report if patients subsequently decide to change treatments. The primary endpoint will be the scores of two key questions compared between the groups: “Did you understand the cost of treatment in today\u27s discussion?” and “Do you think the cost of treatment is important in choosing a treatment?“. The secondary endpoints will be to compare discrepancies between treatments recommended by physicians and those selected by patients, the time required for discussion, other questionnaire factors, and the relationship between Comprehensive Score for Financial Toxicity tool and treatment selection. This will be the first randomized controlled trial to assess the efficacy of software to help patients understand drug cost estimates and whether it subsequently affects treatment choice. This study will be conducted according to the CONSORT statement. All participants will sign a written consent form. The study protocol was reviewed and approved by the Clinical Research Review Board of Nagasaki University (19070801). The protocol (version 1) was designed and will be conducted in accordance with the Declaration of Helsinki (1964) and the Ethical Guidelines for Medical and Health Research Involving Human Subjects (2017). The findings will be disseminated through scientific and professional conferences, and in peer-reviewed journals
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