A successful start-up of an anaerobic membrane bioreactor (AnMBR) coupled mainstream partial nitritation-anammox (PN/A) system: A pilot-scale study on in-situ NOB elimination, AnAOB growth kinetics, and mainstream treatment performance

In this pilot-scale study, an innovative mainstream treatment process that couples the anaerobic membrane reactor (AnMBR) with a one-stage PN/A system was proposed for advancing the concept of carbon neutrality in the municipal wastewater treatment plant. This work demonstrates the start-up procedure of a pilot-scale one-stage PN/A system for mainstream treatment. The 255-day start-up of the one-stage PN/A system involved the cultivation of ammonium-oxidizing bacteria (AOB) from the activated sludge, suppression of nitrite-oxidizing bacteria (NOB), investigation of in-situ growth kinetics of anammox bacteria (AnAOB), and the 50-day operation of the pilot-scale AnMBR-PN/A process for natural mainstream treatment. It is verified in the pilot-scale system for the first time that the in-situ free ammonia (FA) and free nitrous acid (FNA) exposure could effectively eliminate the Nitrospira (the NOB genus) while retaining the Nitosonomas (the AOB genus) community in the suspended sludge. NOB community rebounding was not detected even at the mainstream conditions with low nitrogen concentrations (Influent ammonium concentration=38±6 mg-NH₄⁺-N/L) by intermittent aeration to control the system dissolved oxygen (DO) below 0.5 mg/L. The results of the mainstream treatment showed that the average effluent total nitrogen (TN) in the coupled process was generally lower than 10 mg-N/L, which meets the discharge limits of most prefectures in Japan. The investigated results of the in-situ anammox bacteria (AnAOB) growth kinetics suggested that the promoted start-up strategy of taking advantage of the warm months with higher mainstream temperature to achieve the rapid in-situ growth of the AnAOB is applicable in the investigated regions. From the perspective of the removal performance of the TN and organic substance, the AnMBR-PN/A process has great potential as the layouts of the carbon-neutral mainstream wastewater treatment plants.

Chemical oxygen demand and nitrogen transformation in a large pilot-scale plant with a combined submerged anaerobic membrane bioreactor and one-stage partial nitritation-anammox for treating mainstream wastewater at 25 °C

A novel municipal wastewater treatment process towards energy neutrality and reduced carbon emissions was established by combining a submerged anaerobic membrane bioreactor (SAnMBR) with a one-stage partial nitritation-anammox (PN/A), and was demonstrated at pilot-scale at 25 °C. The overall COD and BOD₅ removal efficiencies were 95.1% and 96.4%, respectively, with 20.3 mg L^-1 COD and 5.2 mg L^-1 BOD₅ remaining in the final effluent. The total nitrogen (TN) removal efficiency was 81.7%, resulting 7.3 mg L^-1 TN was discharged from the system. The biogas yield was 0.222 NL g^-1 COD _removed with a methane content range of 78-81%. Approximately 90% of influent COD was removed in the SAnMBR, and 70% of influent nitrogen was removed in the PN/A. The denitrification which occurred in the PN/A enhanced overall COD and nitrogen removal. The successful operation of this pilot-scale plant indicates the SAnMBR-PN/A process is suitable for treating real municipal wastewater.

Phylogeny of gracillariid leaf-mining moths: evolution of larval behaviour inferred from phylogenomic and Sanger data

Gracillariidae is the most taxonomically diverse cosmopolitan leaf-mining moth family, consisting of nearly 2000 named species in 105 described genera, classified into eight extant subfamilies. The majority of gracillariid species are internal plant feeders as larvae, creating mines and galls in plant tissue. Despite their diversity and ecological adaptations, their phylogenetic relationships, especially among subfamilies, remain uncertain. Genomic data (83 taxa, 589 loci) were integrated with Sanger data (130 taxa, 22 loci), to reconstruct a phylogeny of Gracillariidae. Based on analyses of both datasets combined and analyzed separately, monophyly of Gracillariidae and all its subfamilies, monophyly of the clade "LAMPO" (subfamilies: Lithocolletinae, Acrocercopinae, Marmarinae, Phyllocnistinae, and Oecophyllembiinae) and relationships of its subclade "AMO" (subfamilies: Acrocercopinae, Marmarinae, and Oecophyllembiinae) were strongly supported. A sister-group relationship of Ornixolinae to the remainder of the family, and a monophyletic leaf roller lineage (Callicercops Vári + Parornichinae) + Gracillariinae, as sister to the "LAMPO" clade were supported by the most likely tree. Dating analyses indicate a mid-Cretaceous (105.3 Ma) origin of the family, followed by a rapid diversification into the nine subfamilies predating the Cretaceous-Palaeogene extinction. We hypothesize that advanced larval behaviours, such as making keeled or tentiform blotch mines, rolling leaves and galling, allowed gracillariids to better avoid larval parasitoids allowing them to further diversify. Finally, we stabilize the classification by formally re-establishing the subfamily ranks of Marmarinae stat.rev., Oecophyllembiinae stat.rev. and Parornichinae stat.rev., and erect a new subfamily, Callicercopinae Li, Ohshima and Kawahara to accommodate the enigmatic genus Callicercops.

Prognostic impact of atrial fibrillation under oral anticoagulation therapy in patients with type B acute aortic dissection

Background

Patients with acute aortic dissection (AAD) sometimes are complicated with atrial fibrillation (AF). However, the impact of AF and the use of oral anticoagulation (OAC) on the prognosis of AAD remains unclear. In this study, we evaluated the prognostic impact of AF and OAC therapy in patients with type B AAD.

Methods

Consecutive patients diagnosed with type B AAD between January 2010 and December 2020 in our university hospital were retrospectively analyzed. All patients were divided into 2 groups based on the concomitance with or without AF. The primary endpoint was set as major adverse cardiovascular events (MACEs), including all-cause death, enlargement of aortic diameter, aortic ruptures, and cerebral infarction. Kaplan-Meier survival curves were constructed, and Cox proportional hazards analysis was performed to identify independent predictors of clinical events at 1 year.

Results

A total of 146 patients diagnosed with type B AAD were enrolled, with a mean age of 66±12 years, and 81% of male. Thirty-two patients (22%) experienced MACEs during 272±142 days-observation. Concomitant AF was observed in 27 patients (18%). In the Kaplan-Meier curve analysis, the patients with AF showed significantly higher events than those without AF (log-lank p<0.001). In the multivariate Cox proportional hazards models, presence of AF (HR: 2.402, 95% CI: 1.099–4.978 p=0.029), maximum descending aorta diameter (HR: 1.0366, 95% CI: 1.005–1.064 p=0.023), and age>75 years (HR: 2.635, 95% CI: 1.268–5.388 p=0.011) were independent predictors of MACEs. Regarding OAC in patients with AF, Kaplan-Meier analysis showed that usage of OAC was associated with a higher incidence of MACEs than those without (log-rank, p=0.036)

Conclusion

Presence of AF, enlargement of descending aorta diameter, and age were independent predictors of future MACEs in patients with type B AAD. Additionally, usage of OAC is associated with MACEs in patients with type B AAD complicated with AF.

Funding Acknowledgement

Type of funding sources: None.

Cardiac phenotypes in the acute-phase of microscopic polyangiitis involves dilatation of the left atrium caused by LV diastolic dysfunction

Background

Microscopic polyangiitis (MPA) is a type of primary systemic vasculitis that affects various organs, especially the lungs and kidneys. However, few reports regarding cardiac features of MPA patients were found.

Purpose

We aim to investigate the echocardiographic parameters of acute-phase MPA.

Methods and results

This single-center retrospective study included 15 patients with MPA (Mean age at 72.2±7.1 years, women 73.3%) who underwent echocardiography within two weeks of commencing steroid therapy for induction or reinduction. The echocardiography parameters of the patients were compared with those of 30 age and sex-matched controls. In the MPA group, the commonly affected organs were kidneys (93.3%) and lungs (46.7%); 5 patients (33.3%) had a history of hypertension, which had a similar frequency as the control group. No significant difference in left ventricular (LV) diameter, LV ejection fraction, e', or inferior vena cava diameter was observed between the two groups. However, the MPA group showed significantly higher left atrial (LA) diameter (p=0.033) and LA volume index (p=0.001), as well as higher early diastolic filling velocity (E-wave, p=0.015; E/A, p=0.043; E/e', p=0.041), diastolic pulmonary venous flow velocity (p=0.013), trans-tricuspid pressure gradient (p=0.019), and shorter deceleration time (p=0.038), associated with mildly thicker ventricular walls of left ventricle (LV) than the control group. Moreover, serum levels of C-reactive protein showed significant correlation between E wave (r=0.58, p=0.023), E/A (r=0.67, p=0.006), and deceleration time (r=−0.69, p=0.005) in the MPA group. These results may indicate that in MPA, increased LV stiffness, rather than impairment of LV relaxation was contributed to LV diastolic function, resulting in LA enlargement.

Conclusion

Patients with acute-phase MPA had LA dilatation associated with LV diastolic dysfunction. This finding indicates the importance of cardiac assessment in patients with MPA.

Funding Acknowledgement

Type of funding sources: None.

Sterile inflammation through Ca2+/ Calmodulin-dependent protein kinase II signaling is essential for adverse cardiac remodeling

Introduction and hypothesis

Sterile inflammation is associated with cardiac remodeling in response to non-ischemic stress, but how it is initiated in the absence of cell death and how it is propagated are not well elucidated. We tested the hypothesis that activation of CaMKII in cardiomyocytes and macrophages in response to pressure overload initiates inflammatory responses leading to adverse cardiac remodeling.

Methods and results

Cardiomyocyte specific CaMKIIδ knockout (CKO) mice were subjected to transverse aortic constriction (TAC). CaMKII and NFkB activation were significantly increased in control fl/fl (CTL) but not in CKO hearts. Cardiac mRNA levels for pro-inflammatory cytokines also increased vs sham. These responses were significantly attenuated in the CKO mice. Activated NLRP3 inflammasome was shown by elevated caspase-1 activity in isolated cardiomyocytes of CTL while attenuated in CKO. Macrophage accumulation was attenuated in the CKO and NLRP3 inhibitor MCC950 treated mice. Cardiac fibrosis and subsequent cardiac dysfunction were less impaired in the CKO vs CTL (ejection fraction 43±3% vs 33±5%). Upregulated NLRP3 gene expression, elevated CaMKII and caspase-1 activity were observed in neonatal mouse cardiomyocytes (NMCMs) in response to osmotic stretch. Increased caspase-1 activity was observed in macrophages cultured with media from osmotic-stretched NMCMs and it was attenuated by pretreatment of CaMKII inhibitor KN-93. Coincubation with stretched NMCMs induced inflammatory responses in isolated macrophages from wild-type mice but not in isolated macrophages from KN-93 pretreated mice.

Conclusions

Activated CaMKIIδ in response to pressure overload triggers inflammatory signals including NLRP3 inflammasome cascade in cardiomyocytes. CaMKII could also contribute amplification of inflammasome signal in macrophages leading fibrosis and consequent cardiac dysfunction. CaMKII in cardiomyocytes and macrophages could be a therapeutic target to prevent progression of non-ischemic heart failure.

Funding Acknowledgement

Type of funding sources: None.

Catheter contact angle influences local impedance drop during radiofrequency catheter ablation: insight from a porcine experimental study

Background

Local impedance (LI) at a distal tip of the ablation catheter can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). LI decreases by RFCA, and a degree of LI drop is correlated with lesion size. However, data on the effects of catheter contact angle on lesion size and LI drop were scarce. This study aimed to evaluate the influence of catheter contact angle on lesion size and LI drop in a porcine experimental study.

Methods

Lesions were created on porcine myocardial left ventricles by the LI-sensing ablation catheter (IntellaNav MiFi OI®). Contact force (CF) was measured using pressure to current transducer (load cell). Radiofrequency ablation was performed with a power of 30 Watt and a duration of 30 seconds. CF (0g, 5g, 10g, 20g, and 30g) and catheter angle (30°, 45°, and 90°) were changed in each set (total 120 lesions, n=8 each). LI rise, LI drop by RF application, and lesion size (maximum lesion width, maximum surface width, and maximum lesion depth) were evaluated.

Results

There was no angular dependence in LI rise in all CF. The values of LI rise increased as CF increased. The LI drop also increased as CF increased in all contact angles. Regarding the difference of catheter angles, LI drop with 90° was lower than those with 30° and 45°in CF 10g, 20g, and 30g, respectively. Maximum lesion width and surface width were larger in 30° and 45° than those in 90°, whereas there were no differences in maximum lesion depth.

Conclusion

LI drop in 90° were significantly lower than those in 45° and 30°. Although lesion depths were not different among the three angles, the absolute values of LI drop were different. Caution should be exercised to comprehend the LI drop with catheter angles.

Funding Acknowledgement

Type of funding sources: None.

Echocardiographic features of acute-phase microscopic polyangiitis in Japanese patients: A single-centre retrospective study

OBJECTIVES

Microscopic polyangiitis (MPA) affects various organs. However, echocardiographic findings of MPA are unclear. We aimed to evaluate the echocardiographic features of acute-phase MPA in Japanese patients.

METHODS

This single-centre retrospective study included 15 patients with MPA who underwent echocardiography within 2 weeks of commencing steroid therapy for induction or reinduction. The echocardiography parameters of thetients were compared with those of 30 age- and sex-matched controls.

RESULTS

No significant differences in left ventricular (LV) diameter, LV ejection fraction, or e' were observed between the two groups. However, the MPA group showed a significantly higher left atrial (LA) diameter and LA volume index, as well as higher early diastolic filling velocity, diastolic pulmonary venous flow velocity, and trans-tricuspid pressure gradient, and a shorter deceleration time (DCT). Serum C-reactive protein levels were positively correlated with E wave, E/A, and DCT. These results may indicate that increased LV stiffness, rather than impairment of LV relaxation, contributed to LV diastolic function, resulting in LA enlargement.

CONCLUSIONS

Patients with acute-phase MPA had LA dilatation associated with LV diastolic dysfunction. This finding indicates the importance of cardiac assessment in patients with MPA, especially in patients with a strong inflammatory reaction.

An impact of superior vena cava isolation in non-paroxysmal atrial fibrillation patients with low voltage areas

BACKGROUND

This study aimed to investigate the correlation between left atrial low-voltage areas (LVAs) and an arrhythmogenic superior vena cava (SVC) and the impact on the efficacy of an empiric SVC isolation (SVCI) along with a pulmonary vein isolation (PVI) of non-paroxysmal atrial fibrillation (non-PAF) with or without LVAs.

METHODS

We retrospectively enrolled 153 consecutive patients with non-PAF who underwent a PVI alone (n = 51) or empiric PVI plus an SVCI (n = 102). Left atrial voltage maps were constructed during sinus rhythm to identify the LVAs (<0.5 mV). An arrhythmogenic SVC was defined as firing from the SVC and an SVC associated with the maintenance of AF-like rapid SVC activity.

RESULTS

An arrhythmogenic SVC and LVAs were identified in 28% and 65% of patients with a PVI alone and 36% and 73% of patients with a PVI plus SVCI, respectively (P = .275 and P = .353). In the multivariate analysis a female gender, higher pulmonary artery systolic pressure (PAPs), and arrhythmogenic SVC were associated with the presence of LVAs. In the PVI plus SVCI strategy, there was no significant difference in the atrial tachyarrhythmia/AF-free survival between the patients with and without LVAs after initial and multiple sessions (50% vs. 61%; P = .386, 73% vs. 79%; P = .530), however, differences were observed in the PVI alone group (27% vs. 61%; P = .018, 49% vs. 78%; P = .046).

CONCLUSIONS

The presence of LVAs was associated with an arrhythmogenic SVC. An SVCI may have the potential to compensate for an impaired outcome after a PVI in non-PAF patients with LVAs.

Development of beam emission spectroscopy in the helically symmetric experiment stellarator

This study shows the feasibility of a beam emission spectroscopy (BES) diagnostic in the Helically Symmetric eXperiment (HSX) stellarator for obtaining the spatiotemporal structure of density fluctuation. A beam emission simulation was applied to HSX plasmas to design and optimize viewing chords and to estimate the beam emission spectrum. A Doppler-shifted beam emission spectrum was measured from a 30 kV, 4 A diagnostic neutral beam injected into HSX plasmas. The beam emission was measured with a high-time-resolution avalanche photodiode (APD) assembly to determine the feasibility of BES in HSX. For HSX plasmas heated by 28 GHz electron cyclotron heating, a mode around f = 15 kHz was observed in the BES signal. The coherence between the BES signal and the density fluctuation measured by an interferometer system was significant. A plan for improving the BES system to enable the measurement of higher frequency related to turbulent transport is presented. The array of sightlines proposed in this study can be used to measure beam emission with a Doppler shift larger than 3 nm (blue shift), which enables the use of a wide passband interference filter to obtain higher throughput. The adoption of a large objective optics and a chilled APD assembly will improve the signal-to-noise ratio.

POS0975 CLINICAL CHARACTERISTICS OF NONRADIOGRAPHIC AXIAL SPONDYLOARTHRITIS IN ASIAN COUNTRIES COMPARED TO OTHER REGIONS: RESULTS OF THE INTERNATIONAL CROSS-SECTIONAL ASAS-COMOSPA STUDY

Background:

Clinical characteristics of nonradiographic axial spondyloarthritis (nr-ax-SpA) are highly variable across patients, and may potentially vary across patient populations, particularly due to differing distributions of human leukocyte antigens (HLA) and other genetic factors. The majority of nr-ax-SpA studies have been conducted in Europe, the United States, and small studies are reported from Asia [1].

Objectives:

To delineate clinical characteristics of patients with nr-ax-SpA in Asian countries in comparison to other areas of the world.

Methods:

Utilizing the ASAS-COMOSPA data, an international cross-sectional observational study of SpA patients, we analyzed information on demographics, disease characteristics, comorbidities, and risk factors. Patients were classified by region: Asia (China, Japan, Singapore, South Korea, and Taiwan), and non-Asian countries (Europe, Americas, and Africa); patient characteristics, including diagnosis and treatment, were compared.

Results:

Among 3984 SpA patients included in the study, 1094 were from centers in Asian countries, and 2890 from other regions. 112/780 (14.4%) of axial SpA patients in Asian countries were nr-ax-SpA, substantially less than in other countries (486/1997, 24.3%). Nr-ax-SpA patients in Asian countries compared to nr-ax-SpA in other countries were more likely male (75.9 vs 47.1%), have onset (22.8 vs 27.8 years) and diagnosis (27.2 vs 34.5 years) at younger age, and experience less diagnostic delay (1.88 vs 2.92 years) (Table 1). Nr-ax-SpA patients in Asian countries have higher prevalence of positive HLA-B27 (90.6% vs 61.9%) and fewer peripheral signs such as arthritis, enthesitis, or dactylitis (53.6% vs 66.3%) but have similar rate of extra-articular manifestations (psoriasis, IBD, or uveitis) and co-morbidities. Disease activity, functional impairment, and inflammation on MRI were less in nr-ax-SpA patients in Asian countries. NSAIDs response was higher and use of methotrexate and b-DMARDs were lower among nr-ax-SpA in Asian countries.

Conclusion:

Among axial SpA patients, substantially lower frequency of nr-ax-SpA was observed in Asian countries compared to other regions of the world. Nr-ax-SpA patients in Asian countries were predominantly male, and had younger disease onset with higher HLA-B27 positivity rate and less peripheral signs, and better response to NSAIDs. These results offer an opportunity to improve both early diagnosis and treatment of nr-ax-SpA patients in Asian countries.

Table 1.

Characteristics of nonradiographic axial SpA in Asia versus non-Asian regions

VariablesAsianon-Asian regionsp valueN112486Age at disease diagnosis, yrs27.2 [21.1, 39.6]34.5 [27.7, 41.7]<0.001Diagnostic delay, yrs1.88 [0.27, 5.56]2.92 [0.59, 9.58]0.011Male (%)85 (75.9)229 (47.1)<0.001Sacroiliitis on MRI among tested (%)49 (67.1)341 (82.2)0.005HLA B27 positivity among measured (%)96 (90.6)273 (61.9)<0.001Inflammatory Back Pain (%)107 (95.5)478 (98.4)0.076Arthritis, enthesitis, or dactylitis (%)60 (53.6)322 (66.3)0.016Psoriasis (%)12 (10.7)82 (16.9)0.142Uveitis (%)20 (17.9)81 (16.7)0.870Inflammatory bowel disease (%)5 (4.5)27 (5.6)0.817Elevated CRP (%)37 (33.0)213 (43.8)0.048Physician global assessment (0-10)2.0 [1.0, 5.0]2.0 [1.0, 4.0]0.741Patient global assessment (0-10)3.0 [1.0, 6.0]4.0 [2.0, 6.0]0.012ASDAS-CRP1.40 [0.95, 2.08]1.97 [1.21, 2.78]<0.001BASFI0.8 [0.05, 2.65]2.9 [0.8, 5.6]<0.001Good response to NSAIDs (%)80 (71.4)272 (56.0)0.004Methotrexate use (%)18 (16.1)134 (27.6)0.016Biological DMARDs use (%)27 (24.1)191 (39.3)0.004

References:

[1]López-Medina C, Ramiro S, van der Heijde D, et al. Characteristics and burden of disease in patients with radiographic and non-radiographic axial Spondyloarthritis: a comparison by systematic literature review and meta-analysis. RMD Open. 2019 Nov 21;5(2): e001108.

Acknowledgements:

This study was conducted under the umbrella of the International Society for Spondyloarthritis Assessment (ASAS) and COMOSPA study was supported by unrestricted grants from Pfizer, AbbVie and UCB.

Disclosure of Interests:

Keisuke Ono: None declared, Mitsumasa Kishimoto Speakers bureau: AbbVie, Amgen-Astellas BioPharma, Asahi-Kasei Pharma, Astellas, Ayumi Pharma, BMS, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Gilead, Janssen, Kyowa Kirin, Novartis, Ono Pharma, Pfizer, Tanabe-Mitsubishi, Teijin Pharma, and UCB Pharma, Consultant of: AbbVie, Amgen-Astellas BioPharma, Asahi-Kasei Pharma, Astellas, Ayumi Pharma, BMS, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Gilead, Janssen, Kyowa Kirin, Novartis, Ono Pharma, Pfizer, Tanabe-Mitsubishi, Teijin Pharma, and UCB Pharma, Sho Fukui: None declared, Satoshi Kawaai: None declared, Gautam A. Deshpande: None declared, Kazuki Yoshida Consultant of: OM1, Inc., Grant/research support from: Corrona, LLC, Naomi Ichikawa: None declared, Yuko Kaneko Speakers bureau: AbbVie, Astellas, Ayumi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Hisamitsu, Jansen, Kissei, Pfizer, Sanofi, Takeda, Tanabe-Mitsubishi, and UCB, Taku Kawasaki: None declared, Kazuo Matsui: None declared, Mitsuhiro Morita: None declared, Kurisu Tada: None declared, Naoho Takizawa: None declared, Naoto Tamura: None declared, Atsuo Taniguchi: None declared, Yoshinori Taniguchi: None declared, Shigeyoshi Tsuji: None declared, Shigeto Kobayashi: None declared, Masato Okada: None declared, Clementina López-Medina: None declared, Anna Moltó Consultant of: AbbVie, Pfizer, MSD, Novartis, Gilead, Lilly and UCB, Grant/research support from: AbbVie, Pfizer, MSD, Novartis, Gilead, Lilly and UCB, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, Bayer, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead, Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma, Employee of: Imaging Rheumatology bv. (Director), Maxime Dougados: None declared, Yoshinori Komagata: None declared, Tetsuya Tomita: None declared, Shinya Kaname: None declared.

Development of a multi-channel 320 GHz interferometer for high density plasma measurement in Heliotron J

We report the development of a new interferometer with two stable, high-power, 320 GHz solid-state sources in Heliotron J. A heterodyne Michelson interferometer optical scheme is employed. Two solid-state oscillators are utilized as sources with a fixed frequency at 320 GHz and frequency tunable of 312-324 GHz. Quasi-optical techniques are used for beam transmission. The beam is elongated in the vertical direction with two off-axis parabolic mirrors and injected into the plasma as a sheet beam for the multi-channel measurement (>5 ch.). Passing through the plasma, the beam is reflected at a retroreflector-array installed at the vacuum chamber wall. The retroreflector-array is a bunch of retroreflector structures, which can suppress the beam refraction caused by plasma without much space inside a vacuum chamber unlike a single retroreflector and can facilitate the system design. The source, detectors, and the retroreflector-array are tested to evaluate their basic performance on a tabletop experiment.

Assessment of the cut-off value of quantitative liver-portal vein contrast ratio in the hepatobiliary phase of liver MRI

AIM

To calculate the quantitative liver-portal vein contrast ratio (Q-LPC) cut-off value based on tumour detectability by using receiver operating characteristic (ROC) curves.

MATERIALS AND METHODS

Seventy-four patients with tumours (46 men and 28 women; age, 71 ± 8.1 years), who underwent liver magnetic resonance imaging (MRI) using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) were enrolled. Some patients were found to have multiple tumours. In total, 102 tumour images were evaluated for quantitative liver-spleen contrast ratio (Q-LSC) and Q-LPC 10 minutes after the administration of Gd-EOB-DTPA. Q-LPC and Q-LSC were compared to assess the cut-off values and usefulness. The ROC curve was evaluated using the method for continuously distributed test results, with a free scale of 50 mm. A score of ≥30 out of 50 points was considered good. Cut-off values of Q-LPC and Q-LSC were then calculated. The areas under the ROC curve (AUCs) were also examined and compared.

RESULTS

The AUC-ROC for Q-LPC was 0.858 (95% confidence interval [CI], 0.783-0.933). The cut-off value was determined to be at 1.462. Sensitivity was 0.747, and specificity was 0.852 at the cut-off value. The AUC-ROC for Q-LSC was 0.710 (95% CI, 0.597-0.822). The cut-off value was at 1.543, the sensitivity was 0.560, and the specificity was 0.778 at the cut-off value. A significant difference was noted between the AUCs (p=0.0016).

CONCLUSION

Q-LPC can be used for hepatobiliary phase MRI evaluation.

Association Between Atrial High-Rate Episodes and Ischemic/Major Bleeding Events in Patients With a Cardiac Implantable Electronic Device - A 10-Year, Single-Center Historical Cohort Study

BACKGROUND

An association between atrial high-rate episode (AHRE) and stroke has been reported, although data for the Asian population are limited. This study aimed to investigate the role of AHRE in ischemic and major bleeding events in patients who underwent a cardiac implantable electronic device (CIED) procedure.Methods and Results:This single-center historical cohort study included 710 patients (age: 78±11 years, 374 women) who underwent a CIED-related procedure between October 2009 and September 2019 at Shimane Prefectural Central Hospital (median follow-up period: 4.5 [2.5, 7] years, 3439 person-years). Based on the maximum AHRE burden, patients were divided into: (1) <6 min; (2) ≥6 min to 24-h; and (3) ≥24-h groups. The cumulative incidence of ischemic (ischemic stroke, systemic embolism, and transient ischemic attack) and major bleeding (≥3 Bleeding Academic Research Consortium bleeding criteria) events after the procedure were compared. Uni- and multivariate analyses were performed to identify factors associated with these events. The incidence of both events increased with the rising AHRE burden, being significantly higher in the ≥24-h group than in the <6 min group. Multivariate analysis found age ≥85 years to be the only independent factor associated with both events.

CONCLUSIONS

Longer AHRE duration is associated with a high number of major bleeding and ischemic events. Monitoring these bleeding risks is mandatory when clinicians are considering anticoagulation therapy for such patients.

Revision of the Hawaiian endemic leaf-mining moth genus Philodoria Walsingham (Lepidoptera: Gracillariidae): its conservation status, host plants and descriptions of thirteen new species

Philodoria Walsingham, 1907 is a threatened, Hawaiian endemic genus of leaf-mining gracillariid moths that feeds as larvae on many threatened and endangered Hawaiian endemic plants. These moths are poorly studied and species lack detailed descriptions of morphology, distribution data, and natural history information of adults and immatures. Based on extensive fieldwork from 2013 to 2016, and examination of museum specimens, we describe or redescribe 51 species, 13 which are new species and provide biological and distribution data for 41 species. The 13 new species and their host plants are: P. alakaiensis Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Dubautia sp.), P. funkae Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Wilkesia gymnoxiphium), P. haelaauensis Kobayashi, Johns Kawahara, sp. n. (Urticaceae: Pipturus albidus, P. rockii, Pipturus sp.), P. hesperomanniella Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Hesperomannia arborescens and H. swezeyi), P. keaensis Kobayashi, Johns Kawahara, sp. n. (host unknown), P. keahii Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Remya mauiensis), P. knudseniiella Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Dubautia knudsenii subsp. nagate and D. latifolia), P. lama Kobayashi, Johns Kawahara, sp. n. (Ebanaceae: Diospyros sandwicensis and/or D. hillebrandii), P. limahuliensis Kobayashi, Johns Kawahara, sp. n. (Malvaceae: Hibiscus waimeae subsp. hannerae), P. napaliensis Kobayashi, Johns Kawahara, sp. n. (Ebanaceae: Diospyros sandwicensis and/or D. hillebrandii), P. obamaorum Kobayashi, Johns Kawahara, sp. n. (Urticaceae: Pipturus albidus, Pipturus sp.), P. opuhe Kobayashi, Johns Kawahara, sp. n. (Urticaceae: Urera kaalae and U. sandvicensis) and P. platyphylliella Kobayashi, Johns Kawahara, sp. n. (Asteraceae: Dubautia platyphylla). Types of 30 species were examined, lectotypes of 16 species are designated, and a key to all Philodoria species and all Hawaiian leaf-mining moths are provided. We also present a new Hawaiian name for Philodoria, which we call Hunelele 'elilau, meaning "tiny flier, leaf excavator", referring to their life history and behavior. Philodoria feeds on five herbraceous and woody host plant families, and 41 species persist in localized populations in Hawaii as of 2016. Twelve species (P. alakaiensis, P. funkae, P. haelaauensis, P. hespermanniella, P. kauaulaensis, P. keaensis, P. keahii, P. knudsniiella, P. limahuliensis, P. platyphylliella, P. sciallactis, P. wilkesiella) appear to be severely threatened, as these species are rare or feed exclusively on plants that are endangered or rare. We were unable to document 10 species (P. costalis, P. lipochaetaella, P. micropetala, P. nigrella, P. nigrelloides, P. opuhe, P. pipturiana, P. pipturicola, P. pittosporella, P. spilota) after many efforts to sample in or near their historical habitats. We believe these species may be extinct. Given their restricted distribution and the fact that many species feed on rare and endangered plants, there is a risk that many more Philodoria species may go extinct unless immediate conservation measures are taken.

Sludge yield and degradation of suspended solids by a large pilot-scale anaerobic membrane bioreactor for the treatment of real municipal wastewater at 25 °C

Sludge yield and suspended solid are important factors concerned in the anaerobic treatment of municipal wastewater. In this study, a large pilot-scale anaerobic membrane bioreactor (AnMBR) was constructed for effectively treating real municipal wastewater at an ambient temperature of 25 °C. The sludge yield and the degradation of influent suspended solids were evaluated during the long-term operation of the AnMBR. This reactor with 5.0 m³ effective volume is the largest one-stage submerged AnMBR that has ever been used to treat municipal wastewater. During the long-term operation of 217 days, this AnMBR obtained excellent COD and BOD₅ removal efficiency over 90%. Stable biogas production was also successfully obtained from treating municipal wastewater. The sludge yield of the AnMBR was approximately 0.19-0.26 g MLSS g^-1 COD removed for the treatment of real municipal wastewater. The shortest SRT of the AnMBR was calculated as 29 days for an HRT of 6 h at an empirical MLSS of 10 g L^-1. While the influent suspended solid (SS) contained in the municipal wastewater was completely removed by the AnMBR, only 57%-66% of the influent SS was degraded. The rest of influent SS was directly converted to MLSS instead of being degraded. The AnMBR maintained a stable membrane filtration using a hollow-fiber membrane with a total area of 72 m², realizing a flux of 2.75-17.83 LMH, and the mean transmembrane pressure (TMP) was 0.9-23.5 kPa. An online chemical backwash cleaning system helped to lower the TMP timely using sodium hypochlorite and citric acid when the TMP increased rapidly and reached the rated limit of membrane. This is the first report on demonstrating the successful operation and detailed performance of a large pilot-scale AnMBR applied to the treatment of real municipal wastewater.

Q-band high-performance notch filters at 56 and 77 GHz notches for versatile fusion plasma diagnostics

A six-pole Q-band waveguide filter with a notch frequency above the Q-band has been developed for plasma diagnostics. The previous paper [Nishiura et al., J. Instrum. 10, C12014 (2015)] reported that the notch frequency exists within the standard band. In this study, the newly required notch filter extends the function, which prevents a thorny wave from being mixed into an instrument beyond the standard bandwidth of the waveguide. The mode control technique for cavities realizes a deep and sharp filter shape for Q-band notch filters with 56 and 77 GHz notches, respectively. The former filter has an attenuation more than 50 dB at 56.05 GHz and a bandwidth of 1.1 GHz at -3 dB. The latter filter has an attenuation more than 55 dB at 76.95 GHz and a bandwidth of 1.6 GHz at -3 dB. The electron cyclotron emission imaging and the electron cyclotron emission (ECE) diagnostics for the Q-band implemented a pair of the fabricated filters and demonstrated the ECE measurement successfully in the intense stray radiation from a 56 GHz gyrotron.

Incidence and Demographic Trends for Acute Coronary Syndrome in a Non-Epidemic Area During the Coronavirus Disease Pandemic in Japan - A 2-Institutional Observational Study

Background: We investigated the incidence of acute coronary syndrome (ACS) in a non-epidemic area of coronavirus disease-2019 (COVID-19) in Japan.

Methods and Results: This observational study included consecutive patients admitted for ACS at 2 tertiary hospitals in Izumo City during the pandemic in Japan (n=42, March–July 2020). Although the monthly ACS incidence was comparable, the proportions of delayed admissions and high Killip class (III/IV) were significantly higher in this population than in historical cohorts (n=197, 2015–2019).

Conclusions: Our findings stress the importance of encouraging patients with ACS-related symptoms to visit medical services promptly, especially in non-epidemic areas.

Large pilot-scale submerged anaerobic membrane bioreactor for the treatment of municipal wastewater and biogas production at 25 °C

The aim of this work was to demonstrate the operation of a large pilot-scale submerged anaerobic membrane bioreactor (5.0 m³) for biogas production from municipal wastewater at ambient temperature of 25 °C. To the best of our knowledge, this is the largest one-stage submerged AnMBR that has ever been reported. This AnMBR realized a hydraulic retention time (HRT) of 6 h and a treatment capacity of 20 m³ d^-1, obtaining excellent effluent quality with COD removal efficiency over 90% and BOD₅ removal over 95%. The biogas yield of the AnMBR was 0.25-0.27 L g^-1 removed COD and 0.09-0.10 L L^-1 raw wastewater. The methane content of the biogas was at the range of 75%-81%. The COD and nitrogen mass balance were also identified based on long-term operation. The hollow-fiber membrane module realized a flux of 2.75-17.83 LMH. An online backwash chemical cleaning system helped to lower the transmembrane pressure timely.